[v2,13/15] PCI: cadence: add resume support to cdns_pcie_host_setup()
Commit Message
From: Théo Lebrun <theo.lebrun@bootlin.com>
That function mixes probe structure init and hardware config.
The whole hardware config part must be done at resume after a suspend to
ram.
We therefore pass it a boolean flag determining if we are at probe or at
resume.
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
drivers/pci/controller/cadence/pci-j721e.c | 2 +-
drivers/pci/controller/cadence/pcie-cadence-host.c | 49 ++++++++++++----------
drivers/pci/controller/cadence/pcie-cadence-plat.c | 2 +-
drivers/pci/controller/cadence/pcie-cadence.h | 4 +-
4 files changed, 30 insertions(+), 27 deletions(-)
Comments
In subject, capitalize "Add ..." to follow historical convention.
Also the other driver/pci/ patches.
On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> From: Théo Lebrun <theo.lebrun@bootlin.com>
>
> That function mixes probe structure init and hardware config.
> The whole hardware config part must be done at resume after a suspend to
> ram.
> We therefore pass it a boolean flag determining if we are at probe or at
> resume.
s/That function/cdns_pcie_host_setup()/ so the commit log stands
alone even without the subject line.
s/ram/RAM/
Add blank line between paragraphs (or rewrap into a single paragraph).
This is pretty similar but slightly different from the DWC pattern:
imx6_pcie_probe
... do structure init ...
if (RC)
dw_pcie_host_init
pp->ops->init
imx6_pcie_host_init
imx6_pcie_resume_noirq
imx6_pcie_host_init
j721e_pcie_probe
j721e_pcie_ctrl_init
if (RC)
cdns_pcie_host_setup(true)
j721e_pcie_resume_noirq
j721e_pcie_ctrl_init
if (RC)
cdns_pcie_host_setup(false)
It'd be super nice to have them the same. Passing in a "probe" flag
works but seems a little harder to read in cdns_pcie_host_setup() and
you have to keep track of what it means in the callers.
> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
> ---
> drivers/pci/controller/cadence/pci-j721e.c | 2 +-
> drivers/pci/controller/cadence/pcie-cadence-host.c | 49 ++++++++++++----------
> drivers/pci/controller/cadence/pcie-cadence-plat.c | 2 +-
> drivers/pci/controller/cadence/pcie-cadence.h | 4 +-
> 4 files changed, 30 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
> index 2c87e7728a65..9b343a46da11 100644
> --- a/drivers/pci/controller/cadence/pci-j721e.c
> +++ b/drivers/pci/controller/cadence/pci-j721e.c
> @@ -509,7 +509,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
> gpiod_set_value_cansleep(gpiod, 1);
> }
>
> - ret = cdns_pcie_host_setup(rc);
> + ret = cdns_pcie_host_setup(rc, true);
> if (ret < 0) {
> clk_disable_unprepare(pcie->refclk);
> goto err_pcie_setup;
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
> index 5b14f7ee3c79..dd4d876a9138 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-host.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
> @@ -497,14 +497,14 @@ static int cdns_pcie_host_init(struct device *dev,
> return cdns_pcie_host_init_address_translation(rc);
> }
>
> -int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> +int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
> {
> struct device *dev = rc->pcie.dev;
> struct platform_device *pdev = to_platform_device(dev);
> struct device_node *np = dev->of_node;
> struct pci_host_bridge *bridge;
> enum cdns_pcie_rp_bar bar;
> - struct cdns_pcie *pcie;
> + struct cdns_pcie *pcie = &rc->pcie;
> struct resource *res;
> int ret;
>
> @@ -512,26 +512,27 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> if (!bridge)
> return -ENOMEM;
>
> - pcie = &rc->pcie;
> - pcie->is_rc = true;
> + if (probe) {
> + pcie->is_rc = true;
>
> - rc->vendor_id = 0xffff;
> - of_property_read_u32(np, "vendor-id", &rc->vendor_id);
> + rc->vendor_id = 0xffff;
> + of_property_read_u32(np, "vendor-id", &rc->vendor_id);
>
> - rc->device_id = 0xffff;
> - of_property_read_u32(np, "device-id", &rc->device_id);
> + rc->device_id = 0xffff;
> + of_property_read_u32(np, "device-id", &rc->device_id);
>
> - pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
> - if (IS_ERR(pcie->reg_base)) {
> - dev_err(dev, "missing \"reg\"\n");
> - return PTR_ERR(pcie->reg_base);
> - }
> + pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
> + if (IS_ERR(pcie->reg_base)) {
> + dev_err(dev, "missing \"reg\"\n");
> + return PTR_ERR(pcie->reg_base);
> + }
>
> - res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> - rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
> - if (IS_ERR(rc->cfg_base))
> - return PTR_ERR(rc->cfg_base);
> - rc->cfg_res = res;
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> + rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
> + if (IS_ERR(rc->cfg_base))
> + return PTR_ERR(rc->cfg_base);
> + rc->cfg_res = res;
> + }
>
> if (rc->quirk_detect_quiet_flag)
> cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
> @@ -555,12 +556,14 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> if (ret)
> return ret;
>
> - if (!bridge->ops)
> - bridge->ops = &cdns_pcie_host_ops;
> + if (probe) {
> + if (!bridge->ops)
> + bridge->ops = &cdns_pcie_host_ops;
>
> - ret = pci_host_probe(bridge);
> - if (ret < 0)
> - goto err_init;
> + ret = pci_host_probe(bridge);
> + if (ret < 0)
> + goto err_init;
> + }
>
> return 0;
>
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-plat.c b/drivers/pci/controller/cadence/pcie-cadence-plat.c
> index 0456845dabb9..071423091668 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-plat.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-plat.c
> @@ -86,7 +86,7 @@ static int cdns_plat_pcie_probe(struct platform_device *pdev)
> goto err_get_sync;
> }
>
> - ret = cdns_pcie_host_setup(rc);
> + ret = cdns_pcie_host_setup(rc, true);
> if (ret)
> goto err_init;
> } else {
> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
> index 373cb50fcd15..3b0da889ed64 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence.h
> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
> @@ -515,11 +515,11 @@ static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
> }
>
> #ifdef CONFIG_PCIE_CADENCE_HOST
> -int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
> +int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe);
> void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
> int where);
> #else
> -static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> +static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
> {
> return 0;
> }
>
> --
> 2.39.2
>
On Fri, Jan 26, 2024 at 11:43 PM Bjorn Helgaas <helgaas@kernel.org> wrote:
> On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
..
> It'd be super nice to have them the same. Passing in a "probe" flag
> works but seems a little harder to read in cdns_pcie_host_setup() and
> you have to keep track of what it means in the callers.
FWIW, in another patch with a similar approach I found it (the
approach) a bit ugly and unmaintainable. I would suggest properly
refactoring to create 2+ functions and use as needed.
On Fri, Jan 26, 2024 at 03:43:39PM -0600, Bjorn Helgaas wrote:
> In subject, capitalize "Add ..." to follow historical convention.
> Also the other driver/pci/ patches.
>
> On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> > From: Théo Lebrun <theo.lebrun@bootlin.com>
> >
> > That function mixes probe structure init and hardware config.
> > The whole hardware config part must be done at resume after a suspend to
> > ram.
> > We therefore pass it a boolean flag determining if we are at probe or at
> > resume.
> ...
> This is pretty similar but slightly different from the DWC pattern:
>
> imx6_pcie_probe
> ... do structure init ...
> if (RC)
> dw_pcie_host_init
> pp->ops->init
> imx6_pcie_host_init
>
> imx6_pcie_resume_noirq
> imx6_pcie_host_init
>
> j721e_pcie_probe
> j721e_pcie_ctrl_init
> if (RC)
> cdns_pcie_host_setup(true)
>
> j721e_pcie_resume_noirq
> j721e_pcie_ctrl_init
> if (RC)
> cdns_pcie_host_setup(false)
>
> It'd be super nice to have them the same. Passing in a "probe" flag
> works but seems a little harder to read in cdns_pcie_host_setup() and
> you have to keep track of what it means in the callers.
Maybe a better way to say this is that this patch uses the "probe"
flag to select the behavior of cdns_pcie_host_setup(), and I think it
would be nicer to split those two behaviors into separate functions.
Bjorn
On Mon, Jan 29, 2024 at 04:16:49PM -0600, Bjorn Helgaas wrote:
> On Fri, Jan 26, 2024 at 03:43:39PM -0600, Bjorn Helgaas wrote:
> > On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> > > From: Théo Lebrun <theo.lebrun@bootlin.com>
> > >
> > > That function mixes probe structure init and hardware config.
> > > The whole hardware config part must be done at resume after a suspend to
> > > ram.
> > > We therefore pass it a boolean flag determining if we are at probe or at
> > > resume.
> > ...
> > It'd be super nice to have them the same. Passing in a "probe" flag
> > works but seems a little harder to read in cdns_pcie_host_setup() and
> > you have to keep track of what it means in the callers.
>
> Maybe a better way to say this is that this patch uses the "probe"
> flag to select the behavior of cdns_pcie_host_setup(), and I think it
> would be nicer to split those two behaviors into separate functions.
Oops, sorry, Andy, I wrote this before I saw your similar response
from last Friday. Didn't mean to repeat what you already said!
Bjorn
@@ -509,7 +509,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
gpiod_set_value_cansleep(gpiod, 1);
}
- ret = cdns_pcie_host_setup(rc);
+ ret = cdns_pcie_host_setup(rc, true);
if (ret < 0) {
clk_disable_unprepare(pcie->refclk);
goto err_pcie_setup;
@@ -497,14 +497,14 @@ static int cdns_pcie_host_init(struct device *dev,
return cdns_pcie_host_init_address_translation(rc);
}
-int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
{
struct device *dev = rc->pcie.dev;
struct platform_device *pdev = to_platform_device(dev);
struct device_node *np = dev->of_node;
struct pci_host_bridge *bridge;
enum cdns_pcie_rp_bar bar;
- struct cdns_pcie *pcie;
+ struct cdns_pcie *pcie = &rc->pcie;
struct resource *res;
int ret;
@@ -512,26 +512,27 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
if (!bridge)
return -ENOMEM;
- pcie = &rc->pcie;
- pcie->is_rc = true;
+ if (probe) {
+ pcie->is_rc = true;
- rc->vendor_id = 0xffff;
- of_property_read_u32(np, "vendor-id", &rc->vendor_id);
+ rc->vendor_id = 0xffff;
+ of_property_read_u32(np, "vendor-id", &rc->vendor_id);
- rc->device_id = 0xffff;
- of_property_read_u32(np, "device-id", &rc->device_id);
+ rc->device_id = 0xffff;
+ of_property_read_u32(np, "device-id", &rc->device_id);
- pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
- if (IS_ERR(pcie->reg_base)) {
- dev_err(dev, "missing \"reg\"\n");
- return PTR_ERR(pcie->reg_base);
- }
+ pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
+ if (IS_ERR(pcie->reg_base)) {
+ dev_err(dev, "missing \"reg\"\n");
+ return PTR_ERR(pcie->reg_base);
+ }
- res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
- rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
- if (IS_ERR(rc->cfg_base))
- return PTR_ERR(rc->cfg_base);
- rc->cfg_res = res;
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+ rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
+ if (IS_ERR(rc->cfg_base))
+ return PTR_ERR(rc->cfg_base);
+ rc->cfg_res = res;
+ }
if (rc->quirk_detect_quiet_flag)
cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
@@ -555,12 +556,14 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
if (ret)
return ret;
- if (!bridge->ops)
- bridge->ops = &cdns_pcie_host_ops;
+ if (probe) {
+ if (!bridge->ops)
+ bridge->ops = &cdns_pcie_host_ops;
- ret = pci_host_probe(bridge);
- if (ret < 0)
- goto err_init;
+ ret = pci_host_probe(bridge);
+ if (ret < 0)
+ goto err_init;
+ }
return 0;
@@ -86,7 +86,7 @@ static int cdns_plat_pcie_probe(struct platform_device *pdev)
goto err_get_sync;
}
- ret = cdns_pcie_host_setup(rc);
+ ret = cdns_pcie_host_setup(rc, true);
if (ret)
goto err_init;
} else {
@@ -515,11 +515,11 @@ static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
}
#ifdef CONFIG_PCIE_CADENCE_HOST
-int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe);
void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
int where);
#else
-static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
{
return 0;
}