[v7,2/5] remoteproc: pru: Add APIs to get and put the PRU cores

  From: Tero Kristo <t-kristo@ti.com>

Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
driver to allow client drivers to acquire and release the remoteproc
device associated with a PRU core. The PRU cores are treated as
resources with only one client owning it at a time.

The pru_rproc_get() function returns the rproc handle corresponding
to a PRU core identified by the device tree "ti,prus" property under
the client node. The pru_rproc_put() is the complementary function
to pru_rproc_get().

Co-developed-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
---
 drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
 include/linux/pruss.h          |  56 +++++++++++++
 2 files changed, 193 insertions(+), 5 deletions(-)
 create mode 100644 include/linux/pruss.h
  

Hi Danish,

On 31/10/2022 09:37, MD Danish Anwar wrote:
> From: Tero Kristo <t-kristo@ti.com>
> 
> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
> driver to allow client drivers to acquire and release the remoteproc
> device associated with a PRU core. The PRU cores are treated as
> resources with only one client owning it at a time.
> 
> The pru_rproc_get() function returns the rproc handle corresponding
> to a PRU core identified by the device tree "ti,prus" property under
> the client node. The pru_rproc_put() is the complementary function
> to pru_rproc_get().
> 
> Co-developed-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> ---
>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>  include/linux/pruss.h          |  56 +++++++++++++
>  2 files changed, 193 insertions(+), 5 deletions(-)
>  create mode 100644 include/linux/pruss.h
> 
> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
> index 128bf9912f2c..9ba73cfc29e2 100644
> --- a/drivers/remoteproc/pru_rproc.c
> +++ b/drivers/remoteproc/pru_rproc.c
> @@ -2,12 +2,14 @@
>  /*
>   * PRU-ICSS remoteproc driver for various TI SoCs
>   *
> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>   *
>   * Author(s):
>   *	Suman Anna <s-anna@ti.com>
>   *	Andrew F. Davis <afd@ti.com>
>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
> + *	Puranjay Mohan <p-mohan@ti.com>
> + *	Md Danish Anwar <danishanwar@ti.com>
>   */
>  
>  #include <linux/bitops.h>
> @@ -16,6 +18,7 @@
>  #include <linux/module.h>
>  #include <linux/of_device.h>
>  #include <linux/of_irq.h>
> +#include <linux/pruss.h>
>  #include <linux/pruss_driver.h>
>  #include <linux/remoteproc.h>
>  
> @@ -111,6 +114,8 @@ struct pru_private_data {
>   * @rproc: remoteproc pointer for this PRU core
>   * @data: PRU core specific data
>   * @mem_regions: data for each of the PRU memory regions
> + * @client_np: client device node
> + * @lock: mutex to protect client usage
>   * @fw_name: name of firmware image used during loading
>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
> @@ -126,6 +131,8 @@ struct pru_rproc {
>  	struct rproc *rproc;
>  	const struct pru_private_data *data;
>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
> +	struct device_node *client_np;
> +	struct mutex lock; /* client access lock */
>  	const char *fw_name;
>  	unsigned int *mapped_irq;
>  	struct pru_irq_rsc *pru_interrupt_map;
> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>  }
>  
> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
> +{
> +	struct rproc *rproc;
> +	phandle rproc_phandle;
> +	int ret;
> +
> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
> +	if (ret)
> +		return ERR_PTR(ret);
> +
> +	rproc = rproc_get_by_phandle(rproc_phandle);
> +	if (!rproc) {
> +		ret = -EPROBE_DEFER;
> +		goto err_no_rproc_handle;
> +	}
> +
> +	/* make sure it is PRU rproc */
> +	if (!is_pru_rproc(rproc->dev.parent)) {
> +		rproc_put(rproc);
> +		return ERR_PTR(-ENODEV);
> +	}
> +
> +	get_device(&rproc->dev);

Why do you need a get_device() here?
rproc_get_by_phandle() does it right?

> +
> +	return rproc;
> +
> +err_no_rproc_handle:
> +	rproc_put(rproc);
> +	return ERR_PTR(ret);
> +}
> +
> +/**
> + * pru_rproc_get() - get the PRU rproc instance from a device node
> + * @np: the user/client device node
> + * @index: index to use for the ti,prus property
> + * @pru_id: optional pointer to return the PRU remoteproc processor id
> + *
> + * This function looks through a client device node's "ti,prus" property at
> + * index @index and returns the rproc handle for a valid PRU remote processor if
> + * found. The function allows only one user to own the PRU rproc resource at a
> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
> + * required if the function returns a failure.
> + *
> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
> + * returned.
> + *
> + * Return: rproc handle on success, and an ERR_PTR on failure using one
> + * of the following error values
> + *    -ENODEV if device is not found
> + *    -EBUSY if PRU is already acquired by anyone
> + *    -EPROBE_DEFER is PRU device is not probed yet
> + */
> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> +			    enum pruss_pru_id *pru_id)
> +{
> +	struct rproc *rproc;
> +	struct pru_rproc *pru;
> +	struct device *dev;
> +	int ret;
> +
> +	rproc = __pru_rproc_get(np, index);
> +	if (IS_ERR(rproc))
> +		return rproc;

Why bother doing __pru_rproc_get() if pru->client_np exists?

You could do the below if check first and exit if pru->client_np exists.

> +
> +	pru = rproc->priv;
> +	dev = &rproc->dev;
> +
> +	mutex_lock(&pru->lock);
> +
> +	if (pru->client_np) {
> +		mutex_unlock(&pru->lock);
> +		put_device(dev);
> +		ret = -EBUSY;
> +		goto err_no_rproc_handle;
> +	}
> +
> +	pru->client_np = np;
> +
> +	mutex_unlock(&pru->lock);
> +
> +	if (pru_id)
> +		*pru_id = pru->id;
> +
> +	return rproc;
> +
> +err_no_rproc_handle:
> +	rproc_put(rproc);
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(pru_rproc_get);
> +
> +/**
> + * pru_rproc_put() - release the PRU rproc resource
> + * @rproc: the rproc resource to release
> + *
> + * Releases the PRU rproc resource and makes it available to other
> + * users.
> + */
> +void pru_rproc_put(struct rproc *rproc)
> +{
> +	struct pru_rproc *pru;
> +
> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
> +		return;
> +
> +	pru = rproc->priv;
> +
> +	mutex_lock(&pru->lock);
> +
> +	if (!pru->client_np) {
> +		mutex_unlock(&pru->lock);
> +		return;
> +	}
> +
> +	pru->client_np = NULL;
> +	mutex_unlock(&pru->lock);
> +
> +	rproc_put(rproc);
> +}
> +EXPORT_SYMBOL_GPL(pru_rproc_put);
> +
>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>  {
>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>  	/* PRU1 has its local RAM addresses reversed */
> -	if (pru->id == 1)
> +	if (pru->id == PRUSS_PRU1)

Introduction of PRUSS_PRU0/1 enum could have been a separate patch.

>  		swap(dram0, dram1);
>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>  
> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>  	case RTU0_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case PRU0_IRAM_ADDR_MASK:
> -		pru->id = 0;
> +		pru->id = PRUSS_PRU0;
>  		break;
>  	case TX_PRU1_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case RTU1_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case PRU1_IRAM_ADDR_MASK:
> -		pru->id = 1;
> +		pru->id = PRUSS_PRU1;
>  		break;
>  	default:
>  		ret = -EINVAL;
> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>  	pru->pruss = platform_get_drvdata(ppdev);
>  	pru->rproc = rproc;
>  	pru->fw_name = fw_name;
> +	pru->client_np = NULL;
> +	mutex_init(&pru->lock);
>  
>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>  
>  static struct platform_driver pru_rproc_driver = {
>  	.driver = {
> -		.name   = "pru-rproc",
> +		.name   = PRU_RPROC_DRVNAME,
>  		.of_match_table = pru_rproc_match,
>  		.suppress_bind_attrs = true,
>  	},
> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>  MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
> new file mode 100644
> index 000000000000..fdc719b43db0
> --- /dev/null
> +++ b/include/linux/pruss.h
> @@ -0,0 +1,56 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/**
> + * PRU-ICSS Subsystem user interfaces
> + *
> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
> + *	Suman Anna <s-anna@ti.com>
> + */
> +
> +#ifndef __LINUX_PRUSS_H
> +#define __LINUX_PRUSS_H
> +
> +#include <linux/device.h>
> +#include <linux/types.h>
> +
> +#define PRU_RPROC_DRVNAME "pru-rproc"
> +
> +/*
> + * enum pruss_pru_id - PRU core identifiers
> + */
> +enum pruss_pru_id {
> +	PRUSS_PRU0 = 0,
> +	PRUSS_PRU1,
> +	PRUSS_NUM_PRUS,
> +};
> +
> +struct device_node;
> +
> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
> +
> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> +			    enum pruss_pru_id *pru_id);
> +void pru_rproc_put(struct rproc *rproc);
> +
> +#else
> +
> +static inline struct rproc *
> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
> +static inline void pru_rproc_put(struct rproc *rproc) { }
> +
> +#endif /* CONFIG_PRU_REMOTEPROC */
> +
> +static inline bool is_pru_rproc(struct device *dev)
> +{
> +	const char *drv_name = dev_driver_string(dev);
> +
> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
> +		return false;
> +
> +	return true;
> +}
> +
> +#endif /* __LINUX_PRUSS_H */

cheers,
-roger
  

Hi Roger,

On 04/11/22 18:25, Roger Quadros wrote:
> Hi Danish,
> 
> On 31/10/2022 09:37, MD Danish Anwar wrote:
>> From: Tero Kristo <t-kristo@ti.com>
>>
>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
>> driver to allow client drivers to acquire and release the remoteproc
>> device associated with a PRU core. The PRU cores are treated as
>> resources with only one client owning it at a time.
>>
>> The pru_rproc_get() function returns the rproc handle corresponding
>> to a PRU core identified by the device tree "ti,prus" property under
>> the client node. The pru_rproc_put() is the complementary function
>> to pru_rproc_get().
>>
>> Co-developed-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
>> ---
>>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>>  include/linux/pruss.h          |  56 +++++++++++++
>>  2 files changed, 193 insertions(+), 5 deletions(-)
>>  create mode 100644 include/linux/pruss.h
>>
>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>> index 128bf9912f2c..9ba73cfc29e2 100644
>> --- a/drivers/remoteproc/pru_rproc.c
>> +++ b/drivers/remoteproc/pru_rproc.c
>> @@ -2,12 +2,14 @@
>>  /*
>>   * PRU-ICSS remoteproc driver for various TI SoCs
>>   *
>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>>   *
>>   * Author(s):
>>   *	Suman Anna <s-anna@ti.com>
>>   *	Andrew F. Davis <afd@ti.com>
>>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
>> + *	Puranjay Mohan <p-mohan@ti.com>
>> + *	Md Danish Anwar <danishanwar@ti.com>
>>   */
>>  
>>  #include <linux/bitops.h>
>> @@ -16,6 +18,7 @@
>>  #include <linux/module.h>
>>  #include <linux/of_device.h>
>>  #include <linux/of_irq.h>
>> +#include <linux/pruss.h>
>>  #include <linux/pruss_driver.h>
>>  #include <linux/remoteproc.h>
>>  
>> @@ -111,6 +114,8 @@ struct pru_private_data {
>>   * @rproc: remoteproc pointer for this PRU core
>>   * @data: PRU core specific data
>>   * @mem_regions: data for each of the PRU memory regions
>> + * @client_np: client device node
>> + * @lock: mutex to protect client usage
>>   * @fw_name: name of firmware image used during loading
>>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
>> @@ -126,6 +131,8 @@ struct pru_rproc {
>>  	struct rproc *rproc;
>>  	const struct pru_private_data *data;
>>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
>> +	struct device_node *client_np;
>> +	struct mutex lock; /* client access lock */
>>  	const char *fw_name;
>>  	unsigned int *mapped_irq;
>>  	struct pru_irq_rsc *pru_interrupt_map;
>> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>>  }
>>  
>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
>> +{
>> +	struct rproc *rproc;
>> +	phandle rproc_phandle;
>> +	int ret;
>> +
>> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
>> +	if (ret)
>> +		return ERR_PTR(ret);
>> +
>> +	rproc = rproc_get_by_phandle(rproc_phandle);
>> +	if (!rproc) {
>> +		ret = -EPROBE_DEFER;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	/* make sure it is PRU rproc */
>> +	if (!is_pru_rproc(rproc->dev.parent)) {
>> +		rproc_put(rproc);
>> +		return ERR_PTR(-ENODEV);
>> +	}
>> +
>> +	get_device(&rproc->dev);
> 
> Why do you need a get_device() here?
> rproc_get_by_phandle() does it right?
> 

Yes, this get_device() is not required. I'll remove it.

>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +
>> +/**
>> + * pru_rproc_get() - get the PRU rproc instance from a device node
>> + * @np: the user/client device node
>> + * @index: index to use for the ti,prus property
>> + * @pru_id: optional pointer to return the PRU remoteproc processor id
>> + *
>> + * This function looks through a client device node's "ti,prus" property at
>> + * index @index and returns the rproc handle for a valid PRU remote processor if
>> + * found. The function allows only one user to own the PRU rproc resource at a
>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
>> + * required if the function returns a failure.
>> + *
>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
>> + * returned.
>> + *
>> + * Return: rproc handle on success, and an ERR_PTR on failure using one
>> + * of the following error values
>> + *    -ENODEV if device is not found
>> + *    -EBUSY if PRU is already acquired by anyone
>> + *    -EPROBE_DEFER is PRU device is not probed yet
>> + */
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id)
>> +{
>> +	struct rproc *rproc;
>> +	struct pru_rproc *pru;
>> +	struct device *dev;
>> +	int ret;
>> +
>> +	rproc = __pru_rproc_get(np, index);
>> +	if (IS_ERR(rproc))
>> +		return rproc;
> 
> Why bother doing __pru_rproc_get() if pru->client_np exists?
> 
> You could do the below if check first and exit if pru->client_np exists.
> 

In order to do the below if check, we need to have pru. pru is obtained from
rproc->priv and rproc is obtained from __pru_rproc_get() API. So in order to
run the below if check we need to call the __pru_rproc_get() API first.

So, first we are obtaining rproc from __pru_rproc_get() API and then checking
and exiting if pru->client_np exists.

>> +
>> +	pru = rproc->priv;
>> +	dev = &rproc->dev;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		put_device(dev);
>> +		ret = -EBUSY;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	pru->client_np = np;
>> +
>> +	mutex_unlock(&pru->lock);
>> +
>> +	if (pru_id)
>> +		*pru_id = pru->id;
>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_get);
>> +
>> +/**
>> + * pru_rproc_put() - release the PRU rproc resource
>> + * @rproc: the rproc resource to release
>> + *
>> + * Releases the PRU rproc resource and makes it available to other
>> + * users.
>> + */
>> +void pru_rproc_put(struct rproc *rproc)
>> +{
>> +	struct pru_rproc *pru;
>> +
>> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
>> +		return;
>> +
>> +	pru = rproc->priv;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (!pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		return;
>> +	}
>> +
>> +	pru->client_np = NULL;
>> +	mutex_unlock(&pru->lock);
>> +
>> +	rproc_put(rproc);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_put);
>> +
>>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>>  {
>>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
>> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>>  	/* PRU1 has its local RAM addresses reversed */
>> -	if (pru->id == 1)
>> +	if (pru->id == PRUSS_PRU1)
> 
> Introduction of PRUSS_PRU0/1 enum could have been a separate patch.
> 
>>  		swap(dram0, dram1);
>>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>>  
>> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>>  	case RTU0_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU0_IRAM_ADDR_MASK:
>> -		pru->id = 0;
>> +		pru->id = PRUSS_PRU0;
>>  		break;
>>  	case TX_PRU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case RTU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU1_IRAM_ADDR_MASK:
>> -		pru->id = 1;
>> +		pru->id = PRUSS_PRU1;
>>  		break;
>>  	default:
>>  		ret = -EINVAL;
>> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>>  	pru->pruss = platform_get_drvdata(ppdev);
>>  	pru->rproc = rproc;
>>  	pru->fw_name = fw_name;
>> +	pru->client_np = NULL;
>> +	mutex_init(&pru->lock);
>>  
>>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>>  
>>  static struct platform_driver pru_rproc_driver = {
>>  	.driver = {
>> -		.name   = "pru-rproc",
>> +		.name   = PRU_RPROC_DRVNAME,
>>  		.of_match_table = pru_rproc_match,
>>  		.suppress_bind_attrs = true,
>>  	},
>> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
>> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>>  MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
>> new file mode 100644
>> index 000000000000..fdc719b43db0
>> --- /dev/null
>> +++ b/include/linux/pruss.h
>> @@ -0,0 +1,56 @@
>> +/* SPDX-License-Identifier: GPL-2.0-only */
>> +/**
>> + * PRU-ICSS Subsystem user interfaces
>> + *
>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
>> + *	Suman Anna <s-anna@ti.com>
>> + */
>> +
>> +#ifndef __LINUX_PRUSS_H
>> +#define __LINUX_PRUSS_H
>> +
>> +#include <linux/device.h>
>> +#include <linux/types.h>
>> +
>> +#define PRU_RPROC_DRVNAME "pru-rproc"
>> +
>> +/*
>> + * enum pruss_pru_id - PRU core identifiers
>> + */
>> +enum pruss_pru_id {
>> +	PRUSS_PRU0 = 0,
>> +	PRUSS_PRU1,
>> +	PRUSS_NUM_PRUS,
>> +};
>> +
>> +struct device_node;
>> +
>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
>> +
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id);
>> +void pru_rproc_put(struct rproc *rproc);
>> +
>> +#else
>> +
>> +static inline struct rproc *
>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
>> +{
>> +	return ERR_PTR(-EOPNOTSUPP);
>> +}
>> +
>> +static inline void pru_rproc_put(struct rproc *rproc) { }
>> +
>> +#endif /* CONFIG_PRU_REMOTEPROC */
>> +
>> +static inline bool is_pru_rproc(struct device *dev)
>> +{
>> +	const char *drv_name = dev_driver_string(dev);
>> +
>> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
>> +		return false;
>> +
>> +	return true;
>> +}
>> +
>> +#endif /* __LINUX_PRUSS_H */
> 
> cheers,
> -roger

Thanks and Regards,
Danish.
  

On 08/11/2022 12:08, Md Danish Anwar wrote:
> Hi Roger,
> 
> On 04/11/22 18:25, Roger Quadros wrote:
>> Hi Danish,
>>
>> On 31/10/2022 09:37, MD Danish Anwar wrote:
>>> From: Tero Kristo <t-kristo@ti.com>
>>>
>>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
>>> driver to allow client drivers to acquire and release the remoteproc
>>> device associated with a PRU core. The PRU cores are treated as
>>> resources with only one client owning it at a time.
>>>
>>> The pru_rproc_get() function returns the rproc handle corresponding
>>> to a PRU core identified by the device tree "ti,prus" property under
>>> the client node. The pru_rproc_put() is the complementary function
>>> to pru_rproc_get().
>>>
>>> Co-developed-by: Suman Anna <s-anna@ti.com>
>>> Signed-off-by: Suman Anna <s-anna@ti.com>
>>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>>> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
>>> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
>>> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
>>> ---
>>>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>>>  include/linux/pruss.h          |  56 +++++++++++++
>>>  2 files changed, 193 insertions(+), 5 deletions(-)
>>>  create mode 100644 include/linux/pruss.h
>>>
>>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>>> index 128bf9912f2c..9ba73cfc29e2 100644
>>> --- a/drivers/remoteproc/pru_rproc.c
>>> +++ b/drivers/remoteproc/pru_rproc.c
>>> @@ -2,12 +2,14 @@
>>>  /*
>>>   * PRU-ICSS remoteproc driver for various TI SoCs
>>>   *
>>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
>>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>>>   *
>>>   * Author(s):
>>>   *	Suman Anna <s-anna@ti.com>
>>>   *	Andrew F. Davis <afd@ti.com>
>>>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
>>> + *	Puranjay Mohan <p-mohan@ti.com>
>>> + *	Md Danish Anwar <danishanwar@ti.com>
>>>   */
>>>  
>>>  #include <linux/bitops.h>
>>> @@ -16,6 +18,7 @@
>>>  #include <linux/module.h>
>>>  #include <linux/of_device.h>
>>>  #include <linux/of_irq.h>
>>> +#include <linux/pruss.h>
>>>  #include <linux/pruss_driver.h>
>>>  #include <linux/remoteproc.h>
>>>  
>>> @@ -111,6 +114,8 @@ struct pru_private_data {
>>>   * @rproc: remoteproc pointer for this PRU core
>>>   * @data: PRU core specific data
>>>   * @mem_regions: data for each of the PRU memory regions
>>> + * @client_np: client device node
>>> + * @lock: mutex to protect client usage
>>>   * @fw_name: name of firmware image used during loading
>>>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>>>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
>>> @@ -126,6 +131,8 @@ struct pru_rproc {
>>>  	struct rproc *rproc;
>>>  	const struct pru_private_data *data;
>>>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
>>> +	struct device_node *client_np;
>>> +	struct mutex lock; /* client access lock */
>>>  	const char *fw_name;
>>>  	unsigned int *mapped_irq;
>>>  	struct pru_irq_rsc *pru_interrupt_map;
>>> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>>>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>>>  }
>>>  
>>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
>>> +{
>>> +	struct rproc *rproc;
>>> +	phandle rproc_phandle;
>>> +	int ret;
>>> +
>>> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
>>> +	if (ret)
>>> +		return ERR_PTR(ret);
>>> +
>>> +	rproc = rproc_get_by_phandle(rproc_phandle);
>>> +	if (!rproc) {
>>> +		ret = -EPROBE_DEFER;
>>> +		goto err_no_rproc_handle;
>>> +	}
>>> +
>>> +	/* make sure it is PRU rproc */
>>> +	if (!is_pru_rproc(rproc->dev.parent)) {
>>> +		rproc_put(rproc);
>>> +		return ERR_PTR(-ENODEV);
>>> +	}
>>> +
>>> +	get_device(&rproc->dev);
>>
>> Why do you need a get_device() here?
>> rproc_get_by_phandle() does it right?
>>
> 
> Yes, this get_device() is not required. I'll remove it.
> 
>>> +
>>> +	return rproc;
>>> +
>>> +err_no_rproc_handle:
>>> +	rproc_put(rproc);
>>> +	return ERR_PTR(ret);
>>> +}
>>> +
>>> +/**
>>> + * pru_rproc_get() - get the PRU rproc instance from a device node
>>> + * @np: the user/client device node
>>> + * @index: index to use for the ti,prus property
>>> + * @pru_id: optional pointer to return the PRU remoteproc processor id
>>> + *
>>> + * This function looks through a client device node's "ti,prus" property at
>>> + * index @index and returns the rproc handle for a valid PRU remote processor if
>>> + * found. The function allows only one user to own the PRU rproc resource at a
>>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
>>> + * required if the function returns a failure.
>>> + *
>>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
>>> + * returned.
>>> + *
>>> + * Return: rproc handle on success, and an ERR_PTR on failure using one
>>> + * of the following error values
>>> + *    -ENODEV if device is not found
>>> + *    -EBUSY if PRU is already acquired by anyone
>>> + *    -EPROBE_DEFER is PRU device is not probed yet
>>> + */
>>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>>> +			    enum pruss_pru_id *pru_id)
>>> +{
>>> +	struct rproc *rproc;
>>> +	struct pru_rproc *pru;
>>> +	struct device *dev;
>>> +	int ret;
>>> +
>>> +	rproc = __pru_rproc_get(np, index);
>>> +	if (IS_ERR(rproc))
>>> +		return rproc;
>>
>> Why bother doing __pru_rproc_get() if pru->client_np exists?
>>
>> You could do the below if check first and exit if pru->client_np exists.
>>
> 
> In order to do the below if check, we need to have pru. pru is obtained from
> rproc->priv and rproc is obtained from __pru_rproc_get() API. So in order to
> run the below if check we need to call the __pru_rproc_get() API first.
> 
> So, first we are obtaining rproc from __pru_rproc_get() API and then checking
> and exiting if pru->client_np exists.

Indeed. sorry for the noise.

> 
>>> +
>>> +	pru = rproc->priv;
>>> +	dev = &rproc->dev;
>>> +
>>> +	mutex_lock(&pru->lock);
>>> +
>>> +	if (pru->client_np) {
>>> +		mutex_unlock(&pru->lock);
>>> +		put_device(dev);
>>> +		ret = -EBUSY;
>>> +		goto err_no_rproc_handle;
>>> +	}
>>> +
>>> +	pru->client_np = np;
>>> +
>>> +	mutex_unlock(&pru->lock);
>>> +
>>> +	if (pru_id)
>>> +		*pru_id = pru->id;
>>> +
>>> +	return rproc;
>>> +
>>> +err_no_rproc_handle:
>>> +	rproc_put(rproc);
>>> +	return ERR_PTR(ret);
>>> +}
>>> +EXPORT_SYMBOL_GPL(pru_rproc_get);
>>> +
>>> +/**
>>> + * pru_rproc_put() - release the PRU rproc resource
>>> + * @rproc: the rproc resource to release
>>> + *
>>> + * Releases the PRU rproc resource and makes it available to other
>>> + * users.
>>> + */
>>> +void pru_rproc_put(struct rproc *rproc)
>>> +{
>>> +	struct pru_rproc *pru;
>>> +
>>> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
>>> +		return;
>>> +
>>> +	pru = rproc->priv;
>>> +
>>> +	mutex_lock(&pru->lock);
>>> +
>>> +	if (!pru->client_np) {
>>> +		mutex_unlock(&pru->lock);
>>> +		return;
>>> +	}
>>> +
>>> +	pru->client_np = NULL;
>>> +	mutex_unlock(&pru->lock);
>>> +
>>> +	rproc_put(rproc);
>>> +}
>>> +EXPORT_SYMBOL_GPL(pru_rproc_put);
>>> +
>>>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>>>  {
>>>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
>>> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>>>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>>>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>>>  	/* PRU1 has its local RAM addresses reversed */
>>> -	if (pru->id == 1)
>>> +	if (pru->id == PRUSS_PRU1)
>>
>> Introduction of PRUSS_PRU0/1 enum could have been a separate patch.
>>
>>>  		swap(dram0, dram1);
>>>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>>>  
>>> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>>>  	case RTU0_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case PRU0_IRAM_ADDR_MASK:
>>> -		pru->id = 0;
>>> +		pru->id = PRUSS_PRU0;
>>>  		break;
>>>  	case TX_PRU1_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case RTU1_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case PRU1_IRAM_ADDR_MASK:
>>> -		pru->id = 1;
>>> +		pru->id = PRUSS_PRU1;
>>>  		break;
>>>  	default:
>>>  		ret = -EINVAL;
>>> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>>>  	pru->pruss = platform_get_drvdata(ppdev);
>>>  	pru->rproc = rproc;
>>>  	pru->fw_name = fw_name;
>>> +	pru->client_np = NULL;
>>> +	mutex_init(&pru->lock);
>>>  
>>>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>>>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>>> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>>>  
>>>  static struct platform_driver pru_rproc_driver = {
>>>  	.driver = {
>>> -		.name   = "pru-rproc",
>>> +		.name   = PRU_RPROC_DRVNAME,
>>>  		.of_match_table = pru_rproc_match,
>>>  		.suppress_bind_attrs = true,
>>>  	},
>>> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>>>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>>>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>>>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
>>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
>>> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>>>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>>>  MODULE_LICENSE("GPL v2");
>>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
>>> new file mode 100644
>>> index 000000000000..fdc719b43db0
>>> --- /dev/null
>>> +++ b/include/linux/pruss.h
>>> @@ -0,0 +1,56 @@
>>> +/* SPDX-License-Identifier: GPL-2.0-only */
>>> +/**
>>> + * PRU-ICSS Subsystem user interfaces
>>> + *
>>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
>>> + *	Suman Anna <s-anna@ti.com>
>>> + */
>>> +
>>> +#ifndef __LINUX_PRUSS_H
>>> +#define __LINUX_PRUSS_H
>>> +
>>> +#include <linux/device.h>
>>> +#include <linux/types.h>
>>> +
>>> +#define PRU_RPROC_DRVNAME "pru-rproc"
>>> +
>>> +/*
>>> + * enum pruss_pru_id - PRU core identifiers
>>> + */
>>> +enum pruss_pru_id {
>>> +	PRUSS_PRU0 = 0,
>>> +	PRUSS_PRU1,
>>> +	PRUSS_NUM_PRUS,
>>> +};
>>> +
>>> +struct device_node;
>>> +
>>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
>>> +
>>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>>> +			    enum pruss_pru_id *pru_id);
>>> +void pru_rproc_put(struct rproc *rproc);
>>> +
>>> +#else
>>> +
>>> +static inline struct rproc *
>>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
>>> +{
>>> +	return ERR_PTR(-EOPNOTSUPP);
>>> +}
>>> +
>>> +static inline void pru_rproc_put(struct rproc *rproc) { }
>>> +
>>> +#endif /* CONFIG_PRU_REMOTEPROC */
>>> +
>>> +static inline bool is_pru_rproc(struct device *dev)
>>> +{
>>> +	const char *drv_name = dev_driver_string(dev);
>>> +
>>> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
>>> +		return false;
>>> +
>>> +	return true;
>>> +}
>>> +
>>> +#endif /* __LINUX_PRUSS_H */
>>
>> cheers,
>> -roger
> 
> Thanks and Regards,
> Danish.

cheers,
-roger
  

On Mon, Oct 31, 2022 at 01:07:58PM +0530, MD Danish Anwar wrote:
> From: Tero Kristo <t-kristo@ti.com>
> 
> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
> driver to allow client drivers to acquire and release the remoteproc
> device associated with a PRU core. The PRU cores are treated as
> resources with only one client owning it at a time.
> 
> The pru_rproc_get() function returns the rproc handle corresponding
> to a PRU core identified by the device tree "ti,prus" property under
> the client node. The pru_rproc_put() is the complementary function
> to pru_rproc_get().
> 
> Co-developed-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>

The above is very tedious to look at.  Other than yours, please replace all the
SoBs with Co-developed-by tags.  Even that seems to be an overkill...  Anyways,
for this patch and the other ones in this set.

> ---
>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>  include/linux/pruss.h          |  56 +++++++++++++
>  2 files changed, 193 insertions(+), 5 deletions(-)
>  create mode 100644 include/linux/pruss.h
> 
> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
> index 128bf9912f2c..9ba73cfc29e2 100644
> --- a/drivers/remoteproc/pru_rproc.c
> +++ b/drivers/remoteproc/pru_rproc.c
> @@ -2,12 +2,14 @@
>  /*
>   * PRU-ICSS remoteproc driver for various TI SoCs
>   *
> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>   *
>   * Author(s):
>   *	Suman Anna <s-anna@ti.com>
>   *	Andrew F. Davis <afd@ti.com>
>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
> + *	Puranjay Mohan <p-mohan@ti.com>
> + *	Md Danish Anwar <danishanwar@ti.com>
>   */
>  
>  #include <linux/bitops.h>
> @@ -16,6 +18,7 @@
>  #include <linux/module.h>
>  #include <linux/of_device.h>
>  #include <linux/of_irq.h>
> +#include <linux/pruss.h>
>  #include <linux/pruss_driver.h>
>  #include <linux/remoteproc.h>
>  
> @@ -111,6 +114,8 @@ struct pru_private_data {
>   * @rproc: remoteproc pointer for this PRU core
>   * @data: PRU core specific data
>   * @mem_regions: data for each of the PRU memory regions
> + * @client_np: client device node
> + * @lock: mutex to protect client usage
>   * @fw_name: name of firmware image used during loading
>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
> @@ -126,6 +131,8 @@ struct pru_rproc {
>  	struct rproc *rproc;
>  	const struct pru_private_data *data;
>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
> +	struct device_node *client_np;
> +	struct mutex lock; /* client access lock */

Why is there a comment here when the field is already documented above?

I will wait for you to address Roger's comments before looking at this set
further.

Thanks,
Mathieu

>  	const char *fw_name;
>  	unsigned int *mapped_irq;
>  	struct pru_irq_rsc *pru_interrupt_map;
> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>  }
>  
> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
> +{
> +	struct rproc *rproc;
> +	phandle rproc_phandle;
> +	int ret;
> +
> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
> +	if (ret)
> +		return ERR_PTR(ret);
> +
> +	rproc = rproc_get_by_phandle(rproc_phandle);
> +	if (!rproc) {
> +		ret = -EPROBE_DEFER;
> +		goto err_no_rproc_handle;
> +	}
> +
> +	/* make sure it is PRU rproc */
> +	if (!is_pru_rproc(rproc->dev.parent)) {
> +		rproc_put(rproc);
> +		return ERR_PTR(-ENODEV);
> +	}
> +
> +	get_device(&rproc->dev);
> +
> +	return rproc;
> +
> +err_no_rproc_handle:
> +	rproc_put(rproc);
> +	return ERR_PTR(ret);
> +}
> +
> +/**
> + * pru_rproc_get() - get the PRU rproc instance from a device node
> + * @np: the user/client device node
> + * @index: index to use for the ti,prus property
> + * @pru_id: optional pointer to return the PRU remoteproc processor id
> + *
> + * This function looks through a client device node's "ti,prus" property at
> + * index @index and returns the rproc handle for a valid PRU remote processor if
> + * found. The function allows only one user to own the PRU rproc resource at a
> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
> + * required if the function returns a failure.
> + *
> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
> + * returned.
> + *
> + * Return: rproc handle on success, and an ERR_PTR on failure using one
> + * of the following error values
> + *    -ENODEV if device is not found
> + *    -EBUSY if PRU is already acquired by anyone
> + *    -EPROBE_DEFER is PRU device is not probed yet
> + */
> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> +			    enum pruss_pru_id *pru_id)
> +{
> +	struct rproc *rproc;
> +	struct pru_rproc *pru;
> +	struct device *dev;
> +	int ret;
> +
> +	rproc = __pru_rproc_get(np, index);
> +	if (IS_ERR(rproc))
> +		return rproc;
> +
> +	pru = rproc->priv;
> +	dev = &rproc->dev;
> +
> +	mutex_lock(&pru->lock);
> +
> +	if (pru->client_np) {
> +		mutex_unlock(&pru->lock);
> +		put_device(dev);
> +		ret = -EBUSY;
> +		goto err_no_rproc_handle;
> +	}
> +
> +	pru->client_np = np;
> +
> +	mutex_unlock(&pru->lock);
> +
> +	if (pru_id)
> +		*pru_id = pru->id;
> +
> +	return rproc;
> +
> +err_no_rproc_handle:
> +	rproc_put(rproc);
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(pru_rproc_get);
> +
> +/**
> + * pru_rproc_put() - release the PRU rproc resource
> + * @rproc: the rproc resource to release
> + *
> + * Releases the PRU rproc resource and makes it available to other
> + * users.
> + */
> +void pru_rproc_put(struct rproc *rproc)
> +{
> +	struct pru_rproc *pru;
> +
> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
> +		return;
> +
> +	pru = rproc->priv;
> +
> +	mutex_lock(&pru->lock);
> +
> +	if (!pru->client_np) {
> +		mutex_unlock(&pru->lock);
> +		return;
> +	}
> +
> +	pru->client_np = NULL;
> +	mutex_unlock(&pru->lock);
> +
> +	rproc_put(rproc);
> +}
> +EXPORT_SYMBOL_GPL(pru_rproc_put);
> +
>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>  {
>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>  	/* PRU1 has its local RAM addresses reversed */
> -	if (pru->id == 1)
> +	if (pru->id == PRUSS_PRU1)
>  		swap(dram0, dram1);
>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>  
> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>  	case RTU0_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case PRU0_IRAM_ADDR_MASK:
> -		pru->id = 0;
> +		pru->id = PRUSS_PRU0;
>  		break;
>  	case TX_PRU1_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case RTU1_IRAM_ADDR_MASK:
>  		fallthrough;
>  	case PRU1_IRAM_ADDR_MASK:
> -		pru->id = 1;
> +		pru->id = PRUSS_PRU1;
>  		break;
>  	default:
>  		ret = -EINVAL;
> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>  	pru->pruss = platform_get_drvdata(ppdev);
>  	pru->rproc = rproc;
>  	pru->fw_name = fw_name;
> +	pru->client_np = NULL;
> +	mutex_init(&pru->lock);
>  
>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>  
>  static struct platform_driver pru_rproc_driver = {
>  	.driver = {
> -		.name   = "pru-rproc",
> +		.name   = PRU_RPROC_DRVNAME,
>  		.of_match_table = pru_rproc_match,
>  		.suppress_bind_attrs = true,
>  	},
> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>  MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
> new file mode 100644
> index 000000000000..fdc719b43db0
> --- /dev/null
> +++ b/include/linux/pruss.h
> @@ -0,0 +1,56 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/**
> + * PRU-ICSS Subsystem user interfaces
> + *
> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
> + *	Suman Anna <s-anna@ti.com>
> + */
> +
> +#ifndef __LINUX_PRUSS_H
> +#define __LINUX_PRUSS_H
> +
> +#include <linux/device.h>
> +#include <linux/types.h>
> +
> +#define PRU_RPROC_DRVNAME "pru-rproc"
> +
> +/*
> + * enum pruss_pru_id - PRU core identifiers
> + */
> +enum pruss_pru_id {
> +	PRUSS_PRU0 = 0,
> +	PRUSS_PRU1,
> +	PRUSS_NUM_PRUS,
> +};
> +
> +struct device_node;
> +
> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
> +
> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> +			    enum pruss_pru_id *pru_id);
> +void pru_rproc_put(struct rproc *rproc);
> +
> +#else
> +
> +static inline struct rproc *
> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
> +static inline void pru_rproc_put(struct rproc *rproc) { }
> +
> +#endif /* CONFIG_PRU_REMOTEPROC */
> +
> +static inline bool is_pru_rproc(struct device *dev)
> +{
> +	const char *drv_name = dev_driver_string(dev);
> +
> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
> +		return false;
> +
> +	return true;
> +}
> +
> +#endif /* __LINUX_PRUSS_H */
> -- 
> 2.25.1
>
  

Hi Roger,

I had responded to two of your comments on this patch earlier but missed one
comment. Responding to that comment now.

On 04/11/22 18:25, Roger Quadros wrote:
> Hi Danish,
> 
> On 31/10/2022 09:37, MD Danish Anwar wrote:
>> From: Tero Kristo <t-kristo@ti.com>
>>
>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
>> driver to allow client drivers to acquire and release the remoteproc
>> device associated with a PRU core. The PRU cores are treated as
>> resources with only one client owning it at a time.
>>
>> The pru_rproc_get() function returns the rproc handle corresponding
>> to a PRU core identified by the device tree "ti,prus" property under
>> the client node. The pru_rproc_put() is the complementary function
>> to pru_rproc_get().
>>
>> Co-developed-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
>> ---
>>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>>  include/linux/pruss.h          |  56 +++++++++++++
>>  2 files changed, 193 insertions(+), 5 deletions(-)
>>  create mode 100644 include/linux/pruss.h
>>
>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>> index 128bf9912f2c..9ba73cfc29e2 100644
>> --- a/drivers/remoteproc/pru_rproc.c
>> +++ b/drivers/remoteproc/pru_rproc.c
>> @@ -2,12 +2,14 @@
>>  /*
>>   * PRU-ICSS remoteproc driver for various TI SoCs
>>   *
>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>>   *
>>   * Author(s):
>>   *	Suman Anna <s-anna@ti.com>
>>   *	Andrew F. Davis <afd@ti.com>
>>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
>> + *	Puranjay Mohan <p-mohan@ti.com>
>> + *	Md Danish Anwar <danishanwar@ti.com>
>>   */
>>  
>>  #include <linux/bitops.h>
>> @@ -16,6 +18,7 @@
>>  #include <linux/module.h>
>>  #include <linux/of_device.h>
>>  #include <linux/of_irq.h>
>> +#include <linux/pruss.h>
>>  #include <linux/pruss_driver.h>
>>  #include <linux/remoteproc.h>
>>  
>> @@ -111,6 +114,8 @@ struct pru_private_data {
>>   * @rproc: remoteproc pointer for this PRU core
>>   * @data: PRU core specific data
>>   * @mem_regions: data for each of the PRU memory regions
>> + * @client_np: client device node
>> + * @lock: mutex to protect client usage
>>   * @fw_name: name of firmware image used during loading
>>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
>> @@ -126,6 +131,8 @@ struct pru_rproc {
>>  	struct rproc *rproc;
>>  	const struct pru_private_data *data;
>>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
>> +	struct device_node *client_np;
>> +	struct mutex lock; /* client access lock */
>>  	const char *fw_name;
>>  	unsigned int *mapped_irq;
>>  	struct pru_irq_rsc *pru_interrupt_map;
>> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>>  }
>>  
>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
>> +{
>> +	struct rproc *rproc;
>> +	phandle rproc_phandle;
>> +	int ret;
>> +
>> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
>> +	if (ret)
>> +		return ERR_PTR(ret);
>> +
>> +	rproc = rproc_get_by_phandle(rproc_phandle);
>> +	if (!rproc) {
>> +		ret = -EPROBE_DEFER;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	/* make sure it is PRU rproc */
>> +	if (!is_pru_rproc(rproc->dev.parent)) {
>> +		rproc_put(rproc);
>> +		return ERR_PTR(-ENODEV);
>> +	}
>> +
>> +	get_device(&rproc->dev);
> 
> Why do you need a get_device() here?
> rproc_get_by_phandle() does it right?
> 
>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +
>> +/**
>> + * pru_rproc_get() - get the PRU rproc instance from a device node
>> + * @np: the user/client device node
>> + * @index: index to use for the ti,prus property
>> + * @pru_id: optional pointer to return the PRU remoteproc processor id
>> + *
>> + * This function looks through a client device node's "ti,prus" property at
>> + * index @index and returns the rproc handle for a valid PRU remote processor if
>> + * found. The function allows only one user to own the PRU rproc resource at a
>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
>> + * required if the function returns a failure.
>> + *
>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
>> + * returned.
>> + *
>> + * Return: rproc handle on success, and an ERR_PTR on failure using one
>> + * of the following error values
>> + *    -ENODEV if device is not found
>> + *    -EBUSY if PRU is already acquired by anyone
>> + *    -EPROBE_DEFER is PRU device is not probed yet
>> + */
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id)
>> +{
>> +	struct rproc *rproc;
>> +	struct pru_rproc *pru;
>> +	struct device *dev;
>> +	int ret;
>> +
>> +	rproc = __pru_rproc_get(np, index);
>> +	if (IS_ERR(rproc))
>> +		return rproc;
> 
> Why bother doing __pru_rproc_get() if pru->client_np exists?
> 
> You could do the below if check first and exit if pru->client_np exists.
> 
>> +
>> +	pru = rproc->priv;
>> +	dev = &rproc->dev;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		put_device(dev);
>> +		ret = -EBUSY;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	pru->client_np = np;
>> +
>> +	mutex_unlock(&pru->lock);
>> +
>> +	if (pru_id)
>> +		*pru_id = pru->id;
>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_get);
>> +
>> +/**
>> + * pru_rproc_put() - release the PRU rproc resource
>> + * @rproc: the rproc resource to release
>> + *
>> + * Releases the PRU rproc resource and makes it available to other
>> + * users.
>> + */
>> +void pru_rproc_put(struct rproc *rproc)
>> +{
>> +	struct pru_rproc *pru;
>> +
>> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
>> +		return;
>> +
>> +	pru = rproc->priv;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (!pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		return;
>> +	}
>> +
>> +	pru->client_np = NULL;
>> +	mutex_unlock(&pru->lock);
>> +
>> +	rproc_put(rproc);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_put);
>> +
>>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>>  {
>>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
>> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>>  	/* PRU1 has its local RAM addresses reversed */
>> -	if (pru->id == 1)
>> +	if (pru->id == PRUSS_PRU1)
> 
> Introduction of PRUSS_PRU0/1 enum could have been a separate patch.
>

Yes, Introduction of PRUSS_PRU0/1 enum could have been a separated patch in the
same series. But from the v1 of this series, this enum has been part of this
patch and that's why I kept it that way. We can introduce a new patch for this
enum (and the APIs that are using the enum) in next version of the series if
it's okay with you and Mathieu.

>>  		swap(dram0, dram1);
>>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>>  
>> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>>  	case RTU0_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU0_IRAM_ADDR_MASK:
>> -		pru->id = 0;
>> +		pru->id = PRUSS_PRU0;
>>  		break;
>>  	case TX_PRU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case RTU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU1_IRAM_ADDR_MASK:
>> -		pru->id = 1;
>> +		pru->id = PRUSS_PRU1;
>>  		break;
>>  	default:
>>  		ret = -EINVAL;
>> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>>  	pru->pruss = platform_get_drvdata(ppdev);
>>  	pru->rproc = rproc;
>>  	pru->fw_name = fw_name;
>> +	pru->client_np = NULL;
>> +	mutex_init(&pru->lock);
>>  
>>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>>  
>>  static struct platform_driver pru_rproc_driver = {
>>  	.driver = {
>> -		.name   = "pru-rproc",
>> +		.name   = PRU_RPROC_DRVNAME,
>>  		.of_match_table = pru_rproc_match,
>>  		.suppress_bind_attrs = true,
>>  	},
>> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
>> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>>  MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
>> new file mode 100644
>> index 000000000000..fdc719b43db0
>> --- /dev/null
>> +++ b/include/linux/pruss.h
>> @@ -0,0 +1,56 @@
>> +/* SPDX-License-Identifier: GPL-2.0-only */
>> +/**
>> + * PRU-ICSS Subsystem user interfaces
>> + *
>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
>> + *	Suman Anna <s-anna@ti.com>
>> + */
>> +
>> +#ifndef __LINUX_PRUSS_H
>> +#define __LINUX_PRUSS_H
>> +
>> +#include <linux/device.h>
>> +#include <linux/types.h>
>> +
>> +#define PRU_RPROC_DRVNAME "pru-rproc"
>> +
>> +/*
>> + * enum pruss_pru_id - PRU core identifiers
>> + */
>> +enum pruss_pru_id {
>> +	PRUSS_PRU0 = 0,
>> +	PRUSS_PRU1,
>> +	PRUSS_NUM_PRUS,
>> +};
>> +
>> +struct device_node;
>> +
>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
>> +
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id);
>> +void pru_rproc_put(struct rproc *rproc);
>> +
>> +#else
>> +
>> +static inline struct rproc *
>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
>> +{
>> +	return ERR_PTR(-EOPNOTSUPP);
>> +}
>> +
>> +static inline void pru_rproc_put(struct rproc *rproc) { }
>> +
>> +#endif /* CONFIG_PRU_REMOTEPROC */
>> +
>> +static inline bool is_pru_rproc(struct device *dev)
>> +{
>> +	const char *drv_name = dev_driver_string(dev);
>> +
>> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
>> +		return false;
>> +
>> +	return true;
>> +}
>> +
>> +#endif /* __LINUX_PRUSS_H */
> 
> cheers,
> -roger

Thanks,
Danish.
  

Hi Mathieu,

On 15/11/22 02:20, Mathieu Poirier wrote:
> On Mon, Oct 31, 2022 at 01:07:58PM +0530, MD Danish Anwar wrote:
>> From: Tero Kristo <t-kristo@ti.com>
>>
>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
>> driver to allow client drivers to acquire and release the remoteproc
>> device associated with a PRU core. The PRU cores are treated as
>> resources with only one client owning it at a time.
>>
>> The pru_rproc_get() function returns the rproc handle corresponding
>> to a PRU core identified by the device tree "ti,prus" property under
>> the client node. The pru_rproc_put() is the complementary function
>> to pru_rproc_get().
>>
>> Co-developed-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Suman Anna <s-anna@ti.com>
>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
>> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> 
> The above is very tedious to look at.  Other than yours, please replace all the
> SoBs with Co-developed-by tags.  Even that seems to be an overkill...  Anyways,
> for this patch and the other ones in this set.
> 

Sure, I will replace all the SoBs (other than mine) with Co-developed by tags
for all the patches in this series.

>> ---
>>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>>  include/linux/pruss.h          |  56 +++++++++++++
>>  2 files changed, 193 insertions(+), 5 deletions(-)
>>  create mode 100644 include/linux/pruss.h
>>
>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>> index 128bf9912f2c..9ba73cfc29e2 100644
>> --- a/drivers/remoteproc/pru_rproc.c
>> +++ b/drivers/remoteproc/pru_rproc.c
>> @@ -2,12 +2,14 @@
>>  /*
>>   * PRU-ICSS remoteproc driver for various TI SoCs
>>   *
>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>>   *
>>   * Author(s):
>>   *	Suman Anna <s-anna@ti.com>
>>   *	Andrew F. Davis <afd@ti.com>
>>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
>> + *	Puranjay Mohan <p-mohan@ti.com>
>> + *	Md Danish Anwar <danishanwar@ti.com>
>>   */
>>  
>>  #include <linux/bitops.h>
>> @@ -16,6 +18,7 @@
>>  #include <linux/module.h>
>>  #include <linux/of_device.h>
>>  #include <linux/of_irq.h>
>> +#include <linux/pruss.h>
>>  #include <linux/pruss_driver.h>
>>  #include <linux/remoteproc.h>
>>  
>> @@ -111,6 +114,8 @@ struct pru_private_data {
>>   * @rproc: remoteproc pointer for this PRU core
>>   * @data: PRU core specific data
>>   * @mem_regions: data for each of the PRU memory regions
>> + * @client_np: client device node
>> + * @lock: mutex to protect client usage
>>   * @fw_name: name of firmware image used during loading
>>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
>> @@ -126,6 +131,8 @@ struct pru_rproc {
>>  	struct rproc *rproc;
>>  	const struct pru_private_data *data;
>>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
>> +	struct device_node *client_np;
>> +	struct mutex lock; /* client access lock */
> 
> Why is there a comment here when the field is already documented above?
> 

I will remove the comment from here.

> I will wait for you to address Roger's comments before looking at this set
> further.
> 

I had addressed two out of three of Roger's comments earlier. I missed one
comment. I have responded to that now. Please have a look at this set.

> Thanks,
> Mathieu
> 
>>  	const char *fw_name;
>>  	unsigned int *mapped_irq;
>>  	struct pru_irq_rsc *pru_interrupt_map;
>> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>>  }
>>  
>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
>> +{
>> +	struct rproc *rproc;
>> +	phandle rproc_phandle;
>> +	int ret;
>> +
>> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
>> +	if (ret)
>> +		return ERR_PTR(ret);
>> +
>> +	rproc = rproc_get_by_phandle(rproc_phandle);
>> +	if (!rproc) {
>> +		ret = -EPROBE_DEFER;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	/* make sure it is PRU rproc */
>> +	if (!is_pru_rproc(rproc->dev.parent)) {
>> +		rproc_put(rproc);
>> +		return ERR_PTR(-ENODEV);
>> +	}
>> +
>> +	get_device(&rproc->dev);
>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +
>> +/**
>> + * pru_rproc_get() - get the PRU rproc instance from a device node
>> + * @np: the user/client device node
>> + * @index: index to use for the ti,prus property
>> + * @pru_id: optional pointer to return the PRU remoteproc processor id
>> + *
>> + * This function looks through a client device node's "ti,prus" property at
>> + * index @index and returns the rproc handle for a valid PRU remote processor if
>> + * found. The function allows only one user to own the PRU rproc resource at a
>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
>> + * required if the function returns a failure.
>> + *
>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
>> + * returned.
>> + *
>> + * Return: rproc handle on success, and an ERR_PTR on failure using one
>> + * of the following error values
>> + *    -ENODEV if device is not found
>> + *    -EBUSY if PRU is already acquired by anyone
>> + *    -EPROBE_DEFER is PRU device is not probed yet
>> + */
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id)
>> +{
>> +	struct rproc *rproc;
>> +	struct pru_rproc *pru;
>> +	struct device *dev;
>> +	int ret;
>> +
>> +	rproc = __pru_rproc_get(np, index);
>> +	if (IS_ERR(rproc))
>> +		return rproc;
>> +
>> +	pru = rproc->priv;
>> +	dev = &rproc->dev;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		put_device(dev);
>> +		ret = -EBUSY;
>> +		goto err_no_rproc_handle;
>> +	}
>> +
>> +	pru->client_np = np;
>> +
>> +	mutex_unlock(&pru->lock);
>> +
>> +	if (pru_id)
>> +		*pru_id = pru->id;
>> +
>> +	return rproc;
>> +
>> +err_no_rproc_handle:
>> +	rproc_put(rproc);
>> +	return ERR_PTR(ret);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_get);
>> +
>> +/**
>> + * pru_rproc_put() - release the PRU rproc resource
>> + * @rproc: the rproc resource to release
>> + *
>> + * Releases the PRU rproc resource and makes it available to other
>> + * users.
>> + */
>> +void pru_rproc_put(struct rproc *rproc)
>> +{
>> +	struct pru_rproc *pru;
>> +
>> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
>> +		return;
>> +
>> +	pru = rproc->priv;
>> +
>> +	mutex_lock(&pru->lock);
>> +
>> +	if (!pru->client_np) {
>> +		mutex_unlock(&pru->lock);
>> +		return;
>> +	}
>> +
>> +	pru->client_np = NULL;
>> +	mutex_unlock(&pru->lock);
>> +
>> +	rproc_put(rproc);
>> +}
>> +EXPORT_SYMBOL_GPL(pru_rproc_put);
>> +
>>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>>  {
>>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
>> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>>  	/* PRU1 has its local RAM addresses reversed */
>> -	if (pru->id == 1)
>> +	if (pru->id == PRUSS_PRU1)
>>  		swap(dram0, dram1);
>>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>>  
>> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>>  	case RTU0_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU0_IRAM_ADDR_MASK:
>> -		pru->id = 0;
>> +		pru->id = PRUSS_PRU0;
>>  		break;
>>  	case TX_PRU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case RTU1_IRAM_ADDR_MASK:
>>  		fallthrough;
>>  	case PRU1_IRAM_ADDR_MASK:
>> -		pru->id = 1;
>> +		pru->id = PRUSS_PRU1;
>>  		break;
>>  	default:
>>  		ret = -EINVAL;
>> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>>  	pru->pruss = platform_get_drvdata(ppdev);
>>  	pru->rproc = rproc;
>>  	pru->fw_name = fw_name;
>> +	pru->client_np = NULL;
>> +	mutex_init(&pru->lock);
>>  
>>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>>  
>>  static struct platform_driver pru_rproc_driver = {
>>  	.driver = {
>> -		.name   = "pru-rproc",
>> +		.name   = PRU_RPROC_DRVNAME,
>>  		.of_match_table = pru_rproc_match,
>>  		.suppress_bind_attrs = true,
>>  	},
>> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
>> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>>  MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
>> new file mode 100644
>> index 000000000000..fdc719b43db0
>> --- /dev/null
>> +++ b/include/linux/pruss.h
>> @@ -0,0 +1,56 @@
>> +/* SPDX-License-Identifier: GPL-2.0-only */
>> +/**
>> + * PRU-ICSS Subsystem user interfaces
>> + *
>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
>> + *	Suman Anna <s-anna@ti.com>
>> + */
>> +
>> +#ifndef __LINUX_PRUSS_H
>> +#define __LINUX_PRUSS_H
>> +
>> +#include <linux/device.h>
>> +#include <linux/types.h>
>> +
>> +#define PRU_RPROC_DRVNAME "pru-rproc"
>> +
>> +/*
>> + * enum pruss_pru_id - PRU core identifiers
>> + */
>> +enum pruss_pru_id {
>> +	PRUSS_PRU0 = 0,
>> +	PRUSS_PRU1,
>> +	PRUSS_NUM_PRUS,
>> +};
>> +
>> +struct device_node;
>> +
>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
>> +
>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>> +			    enum pruss_pru_id *pru_id);
>> +void pru_rproc_put(struct rproc *rproc);
>> +
>> +#else
>> +
>> +static inline struct rproc *
>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
>> +{
>> +	return ERR_PTR(-EOPNOTSUPP);
>> +}
>> +
>> +static inline void pru_rproc_put(struct rproc *rproc) { }
>> +
>> +#endif /* CONFIG_PRU_REMOTEPROC */
>> +
>> +static inline bool is_pru_rproc(struct device *dev)
>> +{
>> +	const char *drv_name = dev_driver_string(dev);
>> +
>> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
>> +		return false;
>> +
>> +	return true;
>> +}
>> +
>> +#endif /* __LINUX_PRUSS_H */
>> -- 
>> 2.25.1
>>

Thanks,
Danish
  

Danish,

On 15/11/2022 07:53, Md Danish Anwar wrote:
> 
> Hi Roger,
> 
> I had responded to two of your comments on this patch earlier but missed one
> comment. Responding to that comment now.
> 
> On 04/11/22 18:25, Roger Quadros wrote:
>> Hi Danish,
>>
>> On 31/10/2022 09:37, MD Danish Anwar wrote:
>>> From: Tero Kristo <t-kristo@ti.com>
>>>
>>> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
>>> driver to allow client drivers to acquire and release the remoteproc
>>> device associated with a PRU core. The PRU cores are treated as
>>> resources with only one client owning it at a time.
>>>
>>> The pru_rproc_get() function returns the rproc handle corresponding
>>> to a PRU core identified by the device tree "ti,prus" property under
>>> the client node. The pru_rproc_put() is the complementary function
>>> to pru_rproc_get().
>>>
>>> Co-developed-by: Suman Anna <s-anna@ti.com>
>>> Signed-off-by: Suman Anna <s-anna@ti.com>
>>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>>> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>>> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
>>> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
>>> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
>>> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
>>> ---
>>>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
>>>  include/linux/pruss.h          |  56 +++++++++++++
>>>  2 files changed, 193 insertions(+), 5 deletions(-)
>>>  create mode 100644 include/linux/pruss.h
>>>
>>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>>> index 128bf9912f2c..9ba73cfc29e2 100644
>>> --- a/drivers/remoteproc/pru_rproc.c
>>> +++ b/drivers/remoteproc/pru_rproc.c
>>> @@ -2,12 +2,14 @@
>>>  /*
>>>   * PRU-ICSS remoteproc driver for various TI SoCs
>>>   *
>>> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
>>> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
>>>   *
>>>   * Author(s):
>>>   *	Suman Anna <s-anna@ti.com>
>>>   *	Andrew F. Davis <afd@ti.com>
>>>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
>>> + *	Puranjay Mohan <p-mohan@ti.com>
>>> + *	Md Danish Anwar <danishanwar@ti.com>
>>>   */
>>>  
>>>  #include <linux/bitops.h>
>>> @@ -16,6 +18,7 @@
>>>  #include <linux/module.h>
>>>  #include <linux/of_device.h>
>>>  #include <linux/of_irq.h>
>>> +#include <linux/pruss.h>
>>>  #include <linux/pruss_driver.h>
>>>  #include <linux/remoteproc.h>
>>>  
>>> @@ -111,6 +114,8 @@ struct pru_private_data {
>>>   * @rproc: remoteproc pointer for this PRU core
>>>   * @data: PRU core specific data
>>>   * @mem_regions: data for each of the PRU memory regions
>>> + * @client_np: client device node
>>> + * @lock: mutex to protect client usage
>>>   * @fw_name: name of firmware image used during loading
>>>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
>>>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
>>> @@ -126,6 +131,8 @@ struct pru_rproc {
>>>  	struct rproc *rproc;
>>>  	const struct pru_private_data *data;
>>>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
>>> +	struct device_node *client_np;
>>> +	struct mutex lock; /* client access lock */
>>>  	const char *fw_name;
>>>  	unsigned int *mapped_irq;
>>>  	struct pru_irq_rsc *pru_interrupt_map;
>>> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
>>>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
>>>  }
>>>  
>>> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
>>> +{
>>> +	struct rproc *rproc;
>>> +	phandle rproc_phandle;
>>> +	int ret;
>>> +
>>> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
>>> +	if (ret)
>>> +		return ERR_PTR(ret);
>>> +
>>> +	rproc = rproc_get_by_phandle(rproc_phandle);
>>> +	if (!rproc) {
>>> +		ret = -EPROBE_DEFER;
>>> +		goto err_no_rproc_handle;
>>> +	}
>>> +
>>> +	/* make sure it is PRU rproc */
>>> +	if (!is_pru_rproc(rproc->dev.parent)) {
>>> +		rproc_put(rproc);
>>> +		return ERR_PTR(-ENODEV);
>>> +	}
>>> +
>>> +	get_device(&rproc->dev);
>>
>> Why do you need a get_device() here?
>> rproc_get_by_phandle() does it right?
>>
>>> +
>>> +	return rproc;
>>> +
>>> +err_no_rproc_handle:
>>> +	rproc_put(rproc);
>>> +	return ERR_PTR(ret);
>>> +}
>>> +
>>> +/**
>>> + * pru_rproc_get() - get the PRU rproc instance from a device node
>>> + * @np: the user/client device node
>>> + * @index: index to use for the ti,prus property
>>> + * @pru_id: optional pointer to return the PRU remoteproc processor id
>>> + *
>>> + * This function looks through a client device node's "ti,prus" property at
>>> + * index @index and returns the rproc handle for a valid PRU remote processor if
>>> + * found. The function allows only one user to own the PRU rproc resource at a
>>> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
>>> + * required if the function returns a failure.
>>> + *
>>> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
>>> + * returned.
>>> + *
>>> + * Return: rproc handle on success, and an ERR_PTR on failure using one
>>> + * of the following error values
>>> + *    -ENODEV if device is not found
>>> + *    -EBUSY if PRU is already acquired by anyone
>>> + *    -EPROBE_DEFER is PRU device is not probed yet
>>> + */
>>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>>> +			    enum pruss_pru_id *pru_id)
>>> +{
>>> +	struct rproc *rproc;
>>> +	struct pru_rproc *pru;
>>> +	struct device *dev;
>>> +	int ret;
>>> +
>>> +	rproc = __pru_rproc_get(np, index);
>>> +	if (IS_ERR(rproc))
>>> +		return rproc;
>>
>> Why bother doing __pru_rproc_get() if pru->client_np exists?
>>
>> You could do the below if check first and exit if pru->client_np exists.
>>
>>> +
>>> +	pru = rproc->priv;
>>> +	dev = &rproc->dev;
>>> +
>>> +	mutex_lock(&pru->lock);
>>> +
>>> +	if (pru->client_np) {
>>> +		mutex_unlock(&pru->lock);
>>> +		put_device(dev);
>>> +		ret = -EBUSY;
>>> +		goto err_no_rproc_handle;
>>> +	}
>>> +
>>> +	pru->client_np = np;
>>> +
>>> +	mutex_unlock(&pru->lock);
>>> +
>>> +	if (pru_id)
>>> +		*pru_id = pru->id;
>>> +
>>> +	return rproc;
>>> +
>>> +err_no_rproc_handle:
>>> +	rproc_put(rproc);
>>> +	return ERR_PTR(ret);
>>> +}
>>> +EXPORT_SYMBOL_GPL(pru_rproc_get);
>>> +
>>> +/**
>>> + * pru_rproc_put() - release the PRU rproc resource
>>> + * @rproc: the rproc resource to release
>>> + *
>>> + * Releases the PRU rproc resource and makes it available to other
>>> + * users.
>>> + */
>>> +void pru_rproc_put(struct rproc *rproc)
>>> +{
>>> +	struct pru_rproc *pru;
>>> +
>>> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
>>> +		return;
>>> +
>>> +	pru = rproc->priv;
>>> +
>>> +	mutex_lock(&pru->lock);
>>> +
>>> +	if (!pru->client_np) {
>>> +		mutex_unlock(&pru->lock);
>>> +		return;
>>> +	}
>>> +
>>> +	pru->client_np = NULL;
>>> +	mutex_unlock(&pru->lock);
>>> +
>>> +	rproc_put(rproc);
>>> +}
>>> +EXPORT_SYMBOL_GPL(pru_rproc_put);
>>> +
>>>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
>>>  {
>>>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
>>> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
>>>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
>>>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
>>>  	/* PRU1 has its local RAM addresses reversed */
>>> -	if (pru->id == 1)
>>> +	if (pru->id == PRUSS_PRU1)
>>
>> Introduction of PRUSS_PRU0/1 enum could have been a separate patch.
>>
> 
> Yes, Introduction of PRUSS_PRU0/1 enum could have been a separated patch in the
> same series. But from the v1 of this series, this enum has been part of this
> patch and that's why I kept it that way. We can introduce a new patch for this
> enum (and the APIs that are using the enum) in next version of the series if
> it's okay with you and Mathieu.
> 

Yes please. Thanks!

>>>  		swap(dram0, dram1);
>>>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
>>>  
>>> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
>>>  	case RTU0_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case PRU0_IRAM_ADDR_MASK:
>>> -		pru->id = 0;
>>> +		pru->id = PRUSS_PRU0;
>>>  		break;
>>>  	case TX_PRU1_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case RTU1_IRAM_ADDR_MASK:
>>>  		fallthrough;
>>>  	case PRU1_IRAM_ADDR_MASK:
>>> -		pru->id = 1;
>>> +		pru->id = PRUSS_PRU1;
>>>  		break;
>>>  	default:
>>>  		ret = -EINVAL;
>>> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
>>>  	pru->pruss = platform_get_drvdata(ppdev);
>>>  	pru->rproc = rproc;
>>>  	pru->fw_name = fw_name;
>>> +	pru->client_np = NULL;
>>> +	mutex_init(&pru->lock);
>>>  
>>>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
>>>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>>> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
>>>  
>>>  static struct platform_driver pru_rproc_driver = {
>>>  	.driver = {
>>> -		.name   = "pru-rproc",
>>> +		.name   = PRU_RPROC_DRVNAME,
>>>  		.of_match_table = pru_rproc_match,
>>>  		.suppress_bind_attrs = true,
>>>  	},
>>> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
>>>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
>>>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
>>>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
>>> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
>>> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
>>>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
>>>  MODULE_LICENSE("GPL v2");
>>> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
>>> new file mode 100644
>>> index 000000000000..fdc719b43db0
>>> --- /dev/null
>>> +++ b/include/linux/pruss.h
>>> @@ -0,0 +1,56 @@
>>> +/* SPDX-License-Identifier: GPL-2.0-only */
>>> +/**
>>> + * PRU-ICSS Subsystem user interfaces
>>> + *
>>> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
>>> + *	Suman Anna <s-anna@ti.com>
>>> + */
>>> +
>>> +#ifndef __LINUX_PRUSS_H
>>> +#define __LINUX_PRUSS_H
>>> +
>>> +#include <linux/device.h>
>>> +#include <linux/types.h>
>>> +
>>> +#define PRU_RPROC_DRVNAME "pru-rproc"
>>> +
>>> +/*
>>> + * enum pruss_pru_id - PRU core identifiers
>>> + */
>>> +enum pruss_pru_id {
>>> +	PRUSS_PRU0 = 0,
>>> +	PRUSS_PRU1,
>>> +	PRUSS_NUM_PRUS,
>>> +};
>>> +
>>> +struct device_node;
>>> +
>>> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
>>> +
>>> +struct rproc *pru_rproc_get(struct device_node *np, int index,
>>> +			    enum pruss_pru_id *pru_id);
>>> +void pru_rproc_put(struct rproc *rproc);
>>> +
>>> +#else
>>> +
>>> +static inline struct rproc *
>>> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
>>> +{
>>> +	return ERR_PTR(-EOPNOTSUPP);
>>> +}
>>> +
>>> +static inline void pru_rproc_put(struct rproc *rproc) { }
>>> +
>>> +#endif /* CONFIG_PRU_REMOTEPROC */
>>> +
>>> +static inline bool is_pru_rproc(struct device *dev)
>>> +{
>>> +	const char *drv_name = dev_driver_string(dev);
>>> +
>>> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
>>> +		return false;
>>> +
>>> +	return true;
>>> +}
>>> +
>>> +#endif /* __LINUX_PRUSS_H */
>>
>> cheers,
>> -roger
> 
> Thanks,
> Danish.

cheers,
-roger
  

On Tue, Nov 15, 2022 at 11:29:19AM +0530, Md Danish Anwar wrote:
> Hi Mathieu,
> 
> On 15/11/22 02:20, Mathieu Poirier wrote:
> > On Mon, Oct 31, 2022 at 01:07:58PM +0530, MD Danish Anwar wrote:
> >> From: Tero Kristo <t-kristo@ti.com>
> >>
> >> Add two new APIs, pru_rproc_get() and pru_rproc_put(), to the PRU
> >> driver to allow client drivers to acquire and release the remoteproc
> >> device associated with a PRU core. The PRU cores are treated as
> >> resources with only one client owning it at a time.
> >>
> >> The pru_rproc_get() function returns the rproc handle corresponding
> >> to a PRU core identified by the device tree "ti,prus" property under
> >> the client node. The pru_rproc_put() is the complementary function
> >> to pru_rproc_get().
> >>
> >> Co-developed-by: Suman Anna <s-anna@ti.com>
> >> Signed-off-by: Suman Anna <s-anna@ti.com>
> >> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> >> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> >> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> >> Co-developed-by: Puranjay Mohan <p-mohan@ti.com>
> >> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>
> >> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> > 
> > The above is very tedious to look at.  Other than yours, please replace all the
> > SoBs with Co-developed-by tags.  Even that seems to be an overkill...  Anyways,
> > for this patch and the other ones in this set.
> > 
> 
> Sure, I will replace all the SoBs (other than mine) with Co-developed by tags
> for all the patches in this series.
> 
> >> ---
> >>  drivers/remoteproc/pru_rproc.c | 142 +++++++++++++++++++++++++++++++--
> >>  include/linux/pruss.h          |  56 +++++++++++++
> >>  2 files changed, 193 insertions(+), 5 deletions(-)
> >>  create mode 100644 include/linux/pruss.h
> >>
> >> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
> >> index 128bf9912f2c..9ba73cfc29e2 100644
> >> --- a/drivers/remoteproc/pru_rproc.c
> >> +++ b/drivers/remoteproc/pru_rproc.c
> >> @@ -2,12 +2,14 @@
> >>  /*
> >>   * PRU-ICSS remoteproc driver for various TI SoCs
> >>   *
> >> - * Copyright (C) 2014-2020 Texas Instruments Incorporated - https://www.ti.com/
> >> + * Copyright (C) 2014-2022 Texas Instruments Incorporated - https://www.ti.com/
> >>   *
> >>   * Author(s):
> >>   *	Suman Anna <s-anna@ti.com>
> >>   *	Andrew F. Davis <afd@ti.com>
> >>   *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
> >> + *	Puranjay Mohan <p-mohan@ti.com>
> >> + *	Md Danish Anwar <danishanwar@ti.com>
> >>   */
> >>  
> >>  #include <linux/bitops.h>
> >> @@ -16,6 +18,7 @@
> >>  #include <linux/module.h>
> >>  #include <linux/of_device.h>
> >>  #include <linux/of_irq.h>
> >> +#include <linux/pruss.h>
> >>  #include <linux/pruss_driver.h>
> >>  #include <linux/remoteproc.h>
> >>  
> >> @@ -111,6 +114,8 @@ struct pru_private_data {
> >>   * @rproc: remoteproc pointer for this PRU core
> >>   * @data: PRU core specific data
> >>   * @mem_regions: data for each of the PRU memory regions
> >> + * @client_np: client device node
> >> + * @lock: mutex to protect client usage
> >>   * @fw_name: name of firmware image used during loading
> >>   * @mapped_irq: virtual interrupt numbers of created fw specific mapping
> >>   * @pru_interrupt_map: pointer to interrupt mapping description (firmware)
> >> @@ -126,6 +131,8 @@ struct pru_rproc {
> >>  	struct rproc *rproc;
> >>  	const struct pru_private_data *data;
> >>  	struct pruss_mem_region mem_regions[PRU_IOMEM_MAX];
> >> +	struct device_node *client_np;
> >> +	struct mutex lock; /* client access lock */
> > 
> > Why is there a comment here when the field is already documented above?
> > 
> 
> I will remove the comment from here.
> 
> > I will wait for you to address Roger's comments before looking at this set
> > further.
> > 
> 
> I had addressed two out of three of Roger's comments earlier. I missed one
> comment. I have responded to that now. Please have a look at this set.

I won't - spin off a new revision after addressing Roger's comments and I will
look at that one.

> 
> > Thanks,
> > Mathieu
> > 
> >>  	const char *fw_name;
> >>  	unsigned int *mapped_irq;
> >>  	struct pru_irq_rsc *pru_interrupt_map;
> >> @@ -146,6 +153,127 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val)
> >>  	writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg);
> >>  }
> >>  
> >> +static struct rproc *__pru_rproc_get(struct device_node *np, int index)
> >> +{
> >> +	struct rproc *rproc;
> >> +	phandle rproc_phandle;
> >> +	int ret;
> >> +
> >> +	ret = of_property_read_u32_index(np, "ti,prus", index, &rproc_phandle);
> >> +	if (ret)
> >> +		return ERR_PTR(ret);
> >> +
> >> +	rproc = rproc_get_by_phandle(rproc_phandle);
> >> +	if (!rproc) {
> >> +		ret = -EPROBE_DEFER;
> >> +		goto err_no_rproc_handle;
> >> +	}
> >> +
> >> +	/* make sure it is PRU rproc */
> >> +	if (!is_pru_rproc(rproc->dev.parent)) {
> >> +		rproc_put(rproc);
> >> +		return ERR_PTR(-ENODEV);
> >> +	}
> >> +
> >> +	get_device(&rproc->dev);
> >> +
> >> +	return rproc;
> >> +
> >> +err_no_rproc_handle:
> >> +	rproc_put(rproc);
> >> +	return ERR_PTR(ret);
> >> +}
> >> +
> >> +/**
> >> + * pru_rproc_get() - get the PRU rproc instance from a device node
> >> + * @np: the user/client device node
> >> + * @index: index to use for the ti,prus property
> >> + * @pru_id: optional pointer to return the PRU remoteproc processor id
> >> + *
> >> + * This function looks through a client device node's "ti,prus" property at
> >> + * index @index and returns the rproc handle for a valid PRU remote processor if
> >> + * found. The function allows only one user to own the PRU rproc resource at a
> >> + * time. Caller must call pru_rproc_put() when done with using the rproc, not
> >> + * required if the function returns a failure.
> >> + *
> >> + * When optional @pru_id pointer is passed the PRU remoteproc processor id is
> >> + * returned.
> >> + *
> >> + * Return: rproc handle on success, and an ERR_PTR on failure using one
> >> + * of the following error values
> >> + *    -ENODEV if device is not found
> >> + *    -EBUSY if PRU is already acquired by anyone
> >> + *    -EPROBE_DEFER is PRU device is not probed yet
> >> + */
> >> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> >> +			    enum pruss_pru_id *pru_id)
> >> +{
> >> +	struct rproc *rproc;
> >> +	struct pru_rproc *pru;
> >> +	struct device *dev;
> >> +	int ret;
> >> +
> >> +	rproc = __pru_rproc_get(np, index);
> >> +	if (IS_ERR(rproc))
> >> +		return rproc;
> >> +
> >> +	pru = rproc->priv;
> >> +	dev = &rproc->dev;
> >> +
> >> +	mutex_lock(&pru->lock);
> >> +
> >> +	if (pru->client_np) {
> >> +		mutex_unlock(&pru->lock);
> >> +		put_device(dev);
> >> +		ret = -EBUSY;
> >> +		goto err_no_rproc_handle;
> >> +	}
> >> +
> >> +	pru->client_np = np;
> >> +
> >> +	mutex_unlock(&pru->lock);
> >> +
> >> +	if (pru_id)
> >> +		*pru_id = pru->id;
> >> +
> >> +	return rproc;
> >> +
> >> +err_no_rproc_handle:
> >> +	rproc_put(rproc);
> >> +	return ERR_PTR(ret);
> >> +}
> >> +EXPORT_SYMBOL_GPL(pru_rproc_get);
> >> +
> >> +/**
> >> + * pru_rproc_put() - release the PRU rproc resource
> >> + * @rproc: the rproc resource to release
> >> + *
> >> + * Releases the PRU rproc resource and makes it available to other
> >> + * users.
> >> + */
> >> +void pru_rproc_put(struct rproc *rproc)
> >> +{
> >> +	struct pru_rproc *pru;
> >> +
> >> +	if (IS_ERR_OR_NULL(rproc) || !is_pru_rproc(rproc->dev.parent))
> >> +		return;
> >> +
> >> +	pru = rproc->priv;
> >> +
> >> +	mutex_lock(&pru->lock);
> >> +
> >> +	if (!pru->client_np) {
> >> +		mutex_unlock(&pru->lock);
> >> +		return;
> >> +	}
> >> +
> >> +	pru->client_np = NULL;
> >> +	mutex_unlock(&pru->lock);
> >> +
> >> +	rproc_put(rproc);
> >> +}
> >> +EXPORT_SYMBOL_GPL(pru_rproc_put);
> >> +
> >>  static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg)
> >>  {
> >>  	return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg);
> >> @@ -438,7 +566,7 @@ static void *pru_d_da_to_va(struct pru_rproc *pru, u32 da, size_t len)
> >>  	dram0 = pruss->mem_regions[PRUSS_MEM_DRAM0];
> >>  	dram1 = pruss->mem_regions[PRUSS_MEM_DRAM1];
> >>  	/* PRU1 has its local RAM addresses reversed */
> >> -	if (pru->id == 1)
> >> +	if (pru->id == PRUSS_PRU1)
> >>  		swap(dram0, dram1);
> >>  	shrd_ram = pruss->mem_regions[PRUSS_MEM_SHRD_RAM2];
> >>  
> >> @@ -747,14 +875,14 @@ static int pru_rproc_set_id(struct pru_rproc *pru)
> >>  	case RTU0_IRAM_ADDR_MASK:
> >>  		fallthrough;
> >>  	case PRU0_IRAM_ADDR_MASK:
> >> -		pru->id = 0;
> >> +		pru->id = PRUSS_PRU0;
> >>  		break;
> >>  	case TX_PRU1_IRAM_ADDR_MASK:
> >>  		fallthrough;
> >>  	case RTU1_IRAM_ADDR_MASK:
> >>  		fallthrough;
> >>  	case PRU1_IRAM_ADDR_MASK:
> >> -		pru->id = 1;
> >> +		pru->id = PRUSS_PRU1;
> >>  		break;
> >>  	default:
> >>  		ret = -EINVAL;
> >> @@ -816,6 +944,8 @@ static int pru_rproc_probe(struct platform_device *pdev)
> >>  	pru->pruss = platform_get_drvdata(ppdev);
> >>  	pru->rproc = rproc;
> >>  	pru->fw_name = fw_name;
> >> +	pru->client_np = NULL;
> >> +	mutex_init(&pru->lock);
> >>  
> >>  	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
> >>  		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> >> @@ -904,7 +1034,7 @@ MODULE_DEVICE_TABLE(of, pru_rproc_match);
> >>  
> >>  static struct platform_driver pru_rproc_driver = {
> >>  	.driver = {
> >> -		.name   = "pru-rproc",
> >> +		.name   = PRU_RPROC_DRVNAME,
> >>  		.of_match_table = pru_rproc_match,
> >>  		.suppress_bind_attrs = true,
> >>  	},
> >> @@ -916,5 +1046,7 @@ module_platform_driver(pru_rproc_driver);
> >>  MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
> >>  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
> >>  MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
> >> +MODULE_AUTHOR("Puranjay Mohan <p-mohan@ti.com>");
> >> +MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
> >>  MODULE_DESCRIPTION("PRU-ICSS Remote Processor Driver");
> >>  MODULE_LICENSE("GPL v2");
> >> diff --git a/include/linux/pruss.h b/include/linux/pruss.h
> >> new file mode 100644
> >> index 000000000000..fdc719b43db0
> >> --- /dev/null
> >> +++ b/include/linux/pruss.h
> >> @@ -0,0 +1,56 @@
> >> +/* SPDX-License-Identifier: GPL-2.0-only */
> >> +/**
> >> + * PRU-ICSS Subsystem user interfaces
> >> + *
> >> + * Copyright (C) 2015-2022 Texas Instruments Incorporated - http://www.ti.com
> >> + *	Suman Anna <s-anna@ti.com>
> >> + */
> >> +
> >> +#ifndef __LINUX_PRUSS_H
> >> +#define __LINUX_PRUSS_H
> >> +
> >> +#include <linux/device.h>
> >> +#include <linux/types.h>
> >> +
> >> +#define PRU_RPROC_DRVNAME "pru-rproc"
> >> +
> >> +/*
> >> + * enum pruss_pru_id - PRU core identifiers
> >> + */
> >> +enum pruss_pru_id {
> >> +	PRUSS_PRU0 = 0,
> >> +	PRUSS_PRU1,
> >> +	PRUSS_NUM_PRUS,
> >> +};
> >> +
> >> +struct device_node;
> >> +
> >> +#if IS_ENABLED(CONFIG_PRU_REMOTEPROC)
> >> +
> >> +struct rproc *pru_rproc_get(struct device_node *np, int index,
> >> +			    enum pruss_pru_id *pru_id);
> >> +void pru_rproc_put(struct rproc *rproc);
> >> +
> >> +#else
> >> +
> >> +static inline struct rproc *
> >> +pru_rproc_get(struct device_node *np, int index, enum pruss_pru_id *pru_id)
> >> +{
> >> +	return ERR_PTR(-EOPNOTSUPP);
> >> +}
> >> +
> >> +static inline void pru_rproc_put(struct rproc *rproc) { }
> >> +
> >> +#endif /* CONFIG_PRU_REMOTEPROC */
> >> +
> >> +static inline bool is_pru_rproc(struct device *dev)
> >> +{
> >> +	const char *drv_name = dev_driver_string(dev);
> >> +
> >> +	if (strncmp(drv_name, PRU_RPROC_DRVNAME, sizeof(PRU_RPROC_DRVNAME)))
> >> +		return false;
> >> +
> >> +	return true;
> >> +}
> >> +
> >> +#endif /* __LINUX_PRUSS_H */
> >> -- 
> >> 2.25.1
> >>
> 
> Thanks,
> Danish