[V3,4/7] drm/amd/pm: setup the framework to support Wifi RFI mitigation feature

  With WBRF feature supported, as a driver responding to the frequencies,
amdgpu driver is able to do shadow pstate switching to mitigate possible
interference(between its (G-)DDR memory clocks and local radio module
frequency bands used by Wifi 6/6e/7).

To make WBRF feature functional, the kernel needs to be configured with
CONFIG_ACPI_WBRF and the platform is equipped with necessary ACPI based
mechanism to get amdgpu driver notified.

Signed-off-by: Evan Quan <evan.quan@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  26 +++
 drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c      |  63 ++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  19 ++
 drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     | 184 ++++++++++++++++++
 drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h |  20 ++
 drivers/gpu/drm/amd/pm/swsmu/smu_internal.h   |   3 +
 6 files changed, 315 insertions(+)
  

On 6/16/23 01:57, Evan Quan wrote:
> With WBRF feature supported, as a driver responding to the frequencies,
> amdgpu driver is able to do shadow pstate switching to mitigate possible
> interference(between its (G-)DDR memory clocks and local radio module
> frequency bands used by Wifi 6/6e/7).
> 
> To make WBRF feature functional, the kernel needs to be configured with
> CONFIG_ACPI_WBRF and the platform is equipped with necessary ACPI based
> mechanism to get amdgpu driver notified.
> 
> Signed-off-by: Evan Quan <evan.quan@amd.com>

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>

> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  26 +++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c      |  63 ++++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  19 ++
>   drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     | 184 ++++++++++++++++++
>   drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h |  20 ++
>   drivers/gpu/drm/amd/pm/swsmu/smu_internal.h   |   3 +
>   6 files changed, 315 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 02b827785e39..2f2ec64ed1b2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -50,6 +50,7 @@
>   #include <linux/hashtable.h>
>   #include <linux/dma-fence.h>
>   #include <linux/pci.h>
> +#include <linux/wbrf.h>
>   
>   #include <drm/ttm/ttm_bo.h>
>   #include <drm/ttm/ttm_placement.h>
> @@ -241,6 +242,7 @@ extern int amdgpu_num_kcq;
>   #define AMDGPU_VCNFW_LOG_SIZE (32 * 1024)
>   extern int amdgpu_vcnfw_log;
>   extern int amdgpu_sg_display;
> +extern int amdgpu_wbrf;
>   
>   #define AMDGPU_VM_MAX_NUM_CTX			4096
>   #define AMDGPU_SG_THRESHOLD			(256*1024*1024)
> @@ -741,6 +743,9 @@ struct amdgpu_reset_domain;
>    */
>   #define AMDGPU_HAS_VRAM(_adev) ((_adev)->gmc.real_vram_size)
>   
> +typedef
> +void (*wbrf_notify_handler) (struct amdgpu_device *adev);
> +
>   struct amdgpu_device {
>   	struct device			*dev;
>   	struct pci_dev			*pdev;
> @@ -1050,6 +1055,8 @@ struct amdgpu_device {
>   
>   	bool                            job_hang;
>   	bool                            dc_enabled;
> +
> +	wbrf_notify_handler		wbrf_event_handler;
>   };
>   
>   static inline struct amdgpu_device *drm_to_adev(struct drm_device *ddev)
> @@ -1381,6 +1388,25 @@ static inline int amdgpu_acpi_smart_shift_update(struct drm_device *dev,
>   						 enum amdgpu_ss ss_state) { return 0; }
>   #endif
>   
> +#if defined(CONFIG_ACPI_WBRF)
> +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev);
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out);
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler);
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev);
> +#else
> +static inline bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev) { return false; }
> +static inline
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out) { return 0; }
> +static inline
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler) { return 0; }
> +static inline
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev) { return 0; }
> +#endif
> +
>   #if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND)
>   bool amdgpu_acpi_is_s3_active(struct amdgpu_device *adev);
>   bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> index aeeec211861c..efbe6dd91d1a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> @@ -1105,3 +1105,66 @@ bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev)
>   }
>   
>   #endif /* CONFIG_SUSPEND */
> +
> +#ifdef CONFIG_ACPI_WBRF
> +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev)
> +{
> +	struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> +
> +	if (!acpi_dev)
> +		return false;
> +
> +	return wbrf_supported_consumer(acpi_dev);
> +}
> +
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out)
> +{
> +	struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> +
> +	if (!acpi_dev)
> +		return -ENODEV;
> +
> +	return wbrf_retrieve_exclusions(acpi_dev, exclusions_out);
> +}
> +
> +#define CPM_GPU_NOTIFY_COMMAND		0x55
> +static void amdgpu_acpi_wbrf_event(acpi_handle handle, u32 event, void *data)
> +{
> +	struct amdgpu_device *adev = (struct amdgpu_device *)data;
> +
> +	if (event == CPM_GPU_NOTIFY_COMMAND &&
> +	    adev->wbrf_event_handler)
> +		adev->wbrf_event_handler(adev);
> +}
> +
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler)
> +{
> +	struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> +
> +	if (!acpi_hdler)
> +		return -ENODEV;
> +
> +	adev->wbrf_event_handler = handler;
> +
> +	return acpi_install_notify_handler(acpi_hdler,
> +					   ACPI_ALL_NOTIFY,
> +					   amdgpu_acpi_wbrf_event,
> +					   adev);
> +}
> +
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev)
> +{
> +	struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> +
> +	if (!acpi_hdler)
> +		return -ENODEV;
> +
> +	adev->wbrf_event_handler = NULL;
> +
> +	return acpi_remove_notify_handler(acpi_hdler,
> +					  ACPI_ALL_NOTIFY,
> +					  amdgpu_acpi_wbrf_event);
> +}
> +#endif
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index b1ca1ab6d6ad..bf82cc192153 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -191,6 +191,7 @@ int amdgpu_smartshift_bias;
>   int amdgpu_use_xgmi_p2p = 1;
>   int amdgpu_vcnfw_log;
>   int amdgpu_sg_display = -1; /* auto */
> +int amdgpu_wbrf = -1;
>   
>   static void amdgpu_drv_delayed_reset_work_handler(struct work_struct *work);
>   
> @@ -948,6 +949,24 @@ MODULE_PARM_DESC(smu_pptable_id,
>   	"specify pptable id to be used (-1 = auto(default) value, 0 = use pptable from vbios, > 0 = soft pptable id)");
>   module_param_named(smu_pptable_id, amdgpu_smu_pptable_id, int, 0444);
>   
> +#ifdef CONFIG_ACPI_WBRF
> +/**
> + * DOC: wbrf (int)
> + * Enable Wifi RFI interference mitigation feature.
> + * Due to electrical and mechanical constraints there may be likely interference of
> + * relatively high-powered harmonics of the (G-)DDR memory clocks with local radio
> + * module frequency bands used by Wifi 6/6e/7. To mitigate the possible RFI interference,
> + * with this feature enabled, PMFW will use either “shadowed P-State” or “P-State” based
> + * on active list of frequencies in-use (to be avoided) as part of initial setting or
> + * P-state transition. However, there may be potential performance impact with this
> + * feature enabled.
> + * (0 = disabled, 1 = enabled, -1 = auto (default setting, will be enabled if supported))
> + */
> +MODULE_PARM_DESC(wbrf,
> +	"Enable Wifi RFI interference mitigation (0 = disabled, 1 = enabled, -1 = auto(default)");
> +module_param_named(wbrf, amdgpu_wbrf, int, 0444);
> +#endif
> +
>   /* These devices are not supported by amdgpu.
>    * They are supported by the mach64, r128, radeon drivers
>    */
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> index 2ddf5198e5c4..89f876cc60e6 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> @@ -1188,6 +1188,163 @@ static int smu_get_thermal_temperature_range(struct smu_context *smu)
>   	return ret;
>   }
>   
> +/**
> + * smu_wbrf_handle_exclusion_ranges - consume the wbrf exclusion ranges
> + *
> + * @smu: smu_context pointer
> + *
> + * Retrieve the wbrf exclusion ranges and send them to PMFW for proper handling.
> + * Returns 0 on success, error on failure.
> + */
> +static int smu_wbrf_handle_exclusion_ranges(struct smu_context *smu)
> +{
> +	struct wbrf_ranges_out wbrf_exclusion = {0};
> +	struct exclusion_range *wifi_bands = wbrf_exclusion.band_list;
> +	struct amdgpu_device *adev = smu->adev;
> +	uint64_t start, end;
> +	int ret, i, j;
> +
> +	ret = amdgpu_acpi_wbrf_retrieve_exclusions(adev, &wbrf_exclusion);
> +	if (ret) {
> +		dev_err(adev->dev, "Failed to retrieve exclusion ranges!\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * The exclusion ranges array we got might be filled with holes and duplicate
> +	 * entries. For example:
> +	 * {(2400, 2500), (0, 0), (6882, 6962), (2400, 2500), (0, 0), (6117, 6189), (0, 0)...}
> +	 * We need to do some sortups to eliminate those holes and duplicate entries.
> +	 * Expected output: {(2400, 2500), (6117, 6189), (6882, 6962), (0, 0)...}
> +	 */
> +	for (i = 0; i < MAX_NUM_OF_WBRF_RANGES; i++) {
> +		start = wifi_bands[i].start;
> +		end = wifi_bands[i].end;
> +
> +		/* get the last valid entry to fill the intermediate hole */
> +		if (!start && !end) {
> +			for (j = MAX_NUM_OF_WBRF_RANGES - 1; j > i; j--)
> +				if (wifi_bands[j].start &&
> +				    wifi_bands[j].end)
> +					break;
> +
> +			if (j > i) {
> +				wifi_bands[i].start = wifi_bands[j].start;
> +				wifi_bands[i].end = wifi_bands[j].end;
> +				wifi_bands[j].start = 0;
> +				wifi_bands[j].end = 0;
> +			}
> +
> +			continue;
> +		}
> +
> +		/* eliminate duplicate entries */
> +		for (j = i + 1; j < MAX_NUM_OF_WBRF_RANGES; j++) {
> +			if ((wifi_bands[j].start == start) &&
> +			     (wifi_bands[j].end == end)) {
> +				wifi_bands[j].start = 0;
> +				wifi_bands[j].end = 0;
> +				continue;
> +			}
> +		}
> +	}
> +
> +	/* Send the sorted wifi_bands to PMFW */
> +	ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);
> +	/* Give it another chance */
> +	if (unlikely(ret == -EBUSY)) {
> +		mdelay(5);
> +		ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);
> +	}
> +
> +	return ret;
> +}
> +
> +/**
> + * smu_wbrf_event_handler - handle notify events
> + *
> + * @adev: struct amdgpu_device pointer
> + *
> + * Calls relevant amdgpu function in response to wbrf event
> + * notification from BIOS.
> + */
> +static void smu_wbrf_event_handler(struct amdgpu_device *adev)
> +{
> +	struct smu_context *smu = adev->powerplay.pp_handle;
> +
> +	smu_wbrf_handle_exclusion_ranges(smu);
> +}
> +
> +/**
> + * smu_wbrf_support_check - check wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Verifies the ACPI interface whether wbrf is supported.
> + */
> +static void smu_wbrf_support_check(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +
> +	smu->wbrf_supported = smu_is_asic_wbrf_supported(smu) &&
> +			      !!amdgpu_wbrf &&
> +			      amdgpu_acpi_is_wbrf_supported(adev);
> +
> +	if (smu->wbrf_supported)
> +		dev_info(adev->dev, "Enabled RF interference mitigations\n");
> +}
> +
> +/**
> + * smu_wbrf_init - init driver wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Verifies the AMD ACPI interfaces and registers with the wbrf
> + * notifier chain if wbrf feature is supported.
> + * Returns 0 on success, error on failure.
> + */
> +static int smu_wbrf_init(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +	int ret;
> +
> +	if (!smu->wbrf_supported)
> +		return 0;
> +
> +	ret = amdgpu_acpi_register_wbrf_notify_handler(adev,
> +						       smu_wbrf_event_handler);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * Some wifiband exclusion ranges may be already there
> +	 * before our driver loaded. To make sure our driver
> +	 * is awared of those exclusion ranges.
> +	 */
> +	ret = smu_wbrf_handle_exclusion_ranges(smu);
> +	if (ret)
> +		dev_err(adev->dev, "Failed to handle wbrf exclusion ranges\n");
> +
> +	return ret;
> +}
> +
> +/**
> + * smu_wbrf_fini - tear down driver wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Unregisters with the wbrf notifier chain.
> + */
> +static void smu_wbrf_fini(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +
> +	if (!smu->wbrf_supported)
> +		return;
> +
> +	amdgpu_acpi_unregister_wbrf_notify_handler(adev);
> +}
> +
>   static int smu_smc_hw_setup(struct smu_context *smu)
>   {
>   	struct smu_feature *feature = &smu->smu_feature;
> @@ -1280,6 +1437,15 @@ static int smu_smc_hw_setup(struct smu_context *smu)
>   	if (ret)
>   		return ret;
>   
> +	/* Enable UclkShadow on wbrf supported */
> +	if (smu->wbrf_supported) {
> +		ret = smu_enable_uclk_shadow(smu, true);
> +		if (ret) {
> +			dev_err(adev->dev, "Failed to enable UclkShadow feature to support wbrf!\n");
> +			return ret;
> +		}
> +	}
> +
>   	/*
>   	 * With SCPM enabled, these actions(and relevant messages) are
>   	 * not needed and permitted.
> @@ -1376,6 +1542,15 @@ static int smu_smc_hw_setup(struct smu_context *smu)
>   	 */
>   	ret = smu_set_min_dcef_deep_sleep(smu,
>   					  smu->smu_table.boot_values.dcefclk / 100);
> +	if (ret) {
> +		dev_err(adev->dev, "Error setting min deepsleep dcefclk\n");
> +		return ret;
> +	}
> +
> +	/* Init wbrf support. Properly setup the notifier */
> +	ret = smu_wbrf_init(smu);
> +	if (ret)
> +		dev_err(adev->dev, "Error during wbrf init call\n");
>   
>   	return ret;
>   }
> @@ -1431,6 +1606,13 @@ static int smu_hw_init(void *handle)
>   		return ret;
>   	}
>   
> +	/*
> +	 * Check whether wbrf is supported. This needs to be done
> +	 * before SMU setup starts since part of SMU configuration
> +	 * relies on this.
> +	 */
> +	smu_wbrf_support_check(smu);
> +
>   	if (smu->is_apu) {
>   		ret = smu_set_gfx_imu_enable(smu);
>   		if (ret)
> @@ -1583,6 +1765,8 @@ static int smu_smc_hw_cleanup(struct smu_context *smu)
>   	struct amdgpu_device *adev = smu->adev;
>   	int ret = 0;
>   
> +	smu_wbrf_fini(smu);
> +
>   	cancel_work_sync(&smu->throttling_logging_work);
>   	cancel_work_sync(&smu->interrupt_work);
>   
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> index 09469c750a96..ff0af3da0be2 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> +++ b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> @@ -573,6 +573,9 @@ struct smu_context
>   	u32 debug_param_reg;
>   	u32 debug_msg_reg;
>   	u32 debug_resp_reg;
> +
> +	/* data structures for wbrf feature support */
> +	bool				wbrf_supported;
>   };
>   
>   struct i2c_adapter;
> @@ -1354,6 +1357,23 @@ struct pptable_funcs {
>   	 * @init_pptable_microcode: Prepare the pptable microcode to upload via PSP
>   	 */
>   	int (*init_pptable_microcode)(struct smu_context *smu);
> +
> +	/**
> +	 * @is_asic_wbrf_supported: check whether PMFW supports the wbrf feature
> +	 */
> +	bool (*is_asic_wbrf_supported)(struct smu_context *smu);
> +
> +	/**
> +	 * @enable_uclk_shadow: Enable the uclk shadow feature on wbrf supported
> +	 */
> +	int (*enable_uclk_shadow)(struct smu_context *smu,
> +				  bool enablement);
> +
> +	/**
> +	 * @set_wbrf_exclusion_ranges: notify SMU the wifi bands occupied
> +	 */
> +	int (*set_wbrf_exclusion_ranges)(struct smu_context *smu,
> +					 struct exclusion_range *exclusion_ranges);
>   };
>   
>   typedef enum {
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> index ceb13c838067..67d7495ab49e 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> +++ b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> @@ -97,6 +97,9 @@
>   #define smu_get_default_config_table_settings(smu, config_table)	smu_ppt_funcs(get_default_config_table_settings, -EOPNOTSUPP, smu, config_table)
>   #define smu_set_config_table(smu, config_table)				smu_ppt_funcs(set_config_table, -EOPNOTSUPP, smu, config_table)
>   #define smu_init_pptable_microcode(smu)					smu_ppt_funcs(init_pptable_microcode, 0, smu)
> +#define smu_is_asic_wbrf_supported(smu)					smu_ppt_funcs(is_asic_wbrf_supported, false, smu)
> +#define smu_enable_uclk_shadow(smu, enablement)				smu_ppt_funcs(enable_uclk_shadow, 0, smu, enablement)
> +#define smu_set_wbrf_exclusion_ranges(smu, exclusion_ranges)		smu_ppt_funcs(set_wbrf_exclusion_ranges, -EOPNOTSUPP, smu, exclusion_ranges)
>   
>   #endif
>   #endif
  

On 6/16/2023 12:27 PM, Evan Quan wrote:
> With WBRF feature supported, as a driver responding to the frequencies,
> amdgpu driver is able to do shadow pstate switching to mitigate possible
> interference(between its (G-)DDR memory clocks and local radio module
> frequency bands used by Wifi 6/6e/7).
> 
> To make WBRF feature functional, the kernel needs to be configured with
> CONFIG_ACPI_WBRF and the platform is equipped with necessary ACPI based
> mechanism to get amdgpu driver notified.
> 
> Signed-off-by: Evan Quan <evan.quan@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  26 +++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c      |  63 ++++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  19 ++
>   drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     | 184 ++++++++++++++++++
>   drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h |  20 ++
>   drivers/gpu/drm/amd/pm/swsmu/smu_internal.h   |   3 +
>   6 files changed, 315 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 02b827785e39..2f2ec64ed1b2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -50,6 +50,7 @@
>   #include <linux/hashtable.h>
>   #include <linux/dma-fence.h>
>   #include <linux/pci.h>
> +#include <linux/wbrf.h>
>   
>   #include <drm/ttm/ttm_bo.h>
>   #include <drm/ttm/ttm_placement.h>
> @@ -241,6 +242,7 @@ extern int amdgpu_num_kcq;
>   #define AMDGPU_VCNFW_LOG_SIZE (32 * 1024)
>   extern int amdgpu_vcnfw_log;
>   extern int amdgpu_sg_display;
> +extern int amdgpu_wbrf;
>   
>   #define AMDGPU_VM_MAX_NUM_CTX			4096
>   #define AMDGPU_SG_THRESHOLD			(256*1024*1024)
> @@ -741,6 +743,9 @@ struct amdgpu_reset_domain;
>    */
>   #define AMDGPU_HAS_VRAM(_adev) ((_adev)->gmc.real_vram_size)
>   
> +typedef
> +void (*wbrf_notify_handler) (struct amdgpu_device *adev);
> +
>   struct amdgpu_device {
>   	struct device			*dev;
>   	struct pci_dev			*pdev;
> @@ -1050,6 +1055,8 @@ struct amdgpu_device {
>   
>   	bool                            job_hang;
>   	bool                            dc_enabled;
> +
> +	wbrf_notify_handler		wbrf_event_handler;
>   };
>   
>   static inline struct amdgpu_device *drm_to_adev(struct drm_device *ddev)
> @@ -1381,6 +1388,25 @@ static inline int amdgpu_acpi_smart_shift_update(struct drm_device *dev,
>   						 enum amdgpu_ss ss_state) { return 0; }
>   #endif
>   
> +#if defined(CONFIG_ACPI_WBRF)
> +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev);
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out);
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler);
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev);
> +#else
> +static inline bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev) { return false; }
> +static inline
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out) { return 0; }
> +static inline
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler) { return 0; }
> +static inline
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev) { return 0; }
> +#endif
> +
>   #if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND)
>   bool amdgpu_acpi_is_s3_active(struct amdgpu_device *adev);
>   bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> index aeeec211861c..efbe6dd91d1a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> @@ -1105,3 +1105,66 @@ bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev)
>   }
>   
>   #endif /* CONFIG_SUSPEND */
> +
> +#ifdef CONFIG_ACPI_WBRF
> +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev)
> +{
> +	struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> +
> +	if (!acpi_dev)
> +		return false;
> +
> +	return wbrf_supported_consumer(acpi_dev);
> +}
> +
> +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> +					 struct wbrf_ranges_out *exclusions_out)
> +{
> +	struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> +
> +	if (!acpi_dev)
> +		return -ENODEV;
> +
> +	return wbrf_retrieve_exclusions(acpi_dev, exclusions_out);
> +}
> +
> +#define CPM_GPU_NOTIFY_COMMAND		0x55
> +static void amdgpu_acpi_wbrf_event(acpi_handle handle, u32 event, void *data)
> +{
> +	struct amdgpu_device *adev = (struct amdgpu_device *)data;
> +
> +	if (event == CPM_GPU_NOTIFY_COMMAND &&
> +	    adev->wbrf_event_handler)
> +		adev->wbrf_event_handler(adev); > +}
> +
> +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> +					     wbrf_notify_handler handler)
> +{
> +	struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> +
> +	if (!acpi_hdler)
> +		return -ENODEV;
> +
> +	adev->wbrf_event_handler = handler;
> +
> +	return acpi_install_notify_handler(acpi_hdler,
> +					   ACPI_ALL_NOTIFY,
> +					   amdgpu_acpi_wbrf_event,
> +					   adev);
> +}
> +
> +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device *adev)
> +{
> +	struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> +
> +	if (!acpi_hdler)
> +		return -ENODEV;
> +
> +	adev->wbrf_event_handler = NULL;
> +
> +	return acpi_remove_notify_handler(acpi_hdler,
> +					  ACPI_ALL_NOTIFY,
> +					  amdgpu_acpi_wbrf_event);
> +}
> +#endif
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index b1ca1ab6d6ad..bf82cc192153 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -191,6 +191,7 @@ int amdgpu_smartshift_bias;
>   int amdgpu_use_xgmi_p2p = 1;
>   int amdgpu_vcnfw_log;
>   int amdgpu_sg_display = -1; /* auto */
> +int amdgpu_wbrf = -1;
>   
>   static void amdgpu_drv_delayed_reset_work_handler(struct work_struct *work);
>   
> @@ -948,6 +949,24 @@ MODULE_PARM_DESC(smu_pptable_id,
>   	"specify pptable id to be used (-1 = auto(default) value, 0 = use pptable from vbios, > 0 = soft pptable id)");
>   module_param_named(smu_pptable_id, amdgpu_smu_pptable_id, int, 0444);
>   
> +#ifdef CONFIG_ACPI_WBRF
> +/**
> + * DOC: wbrf (int)
> + * Enable Wifi RFI interference mitigation feature.
> + * Due to electrical and mechanical constraints there may be likely interference of
> + * relatively high-powered harmonics of the (G-)DDR memory clocks with local radio
> + * module frequency bands used by Wifi 6/6e/7. To mitigate the possible RFI interference,
> + * with this feature enabled, PMFW will use either “shadowed P-State” or “P-State” based
> + * on active list of frequencies in-use (to be avoided) as part of initial setting or
> + * P-state transition. However, there may be potential performance impact with this
> + * feature enabled.
> + * (0 = disabled, 1 = enabled, -1 = auto (default setting, will be enabled if supported))
> + */
> +MODULE_PARM_DESC(wbrf,
> +	"Enable Wifi RFI interference mitigation (0 = disabled, 1 = enabled, -1 = auto(default)");
> +module_param_named(wbrf, amdgpu_wbrf, int, 0444);
> +#endif
> +
>   /* These devices are not supported by amdgpu.
>    * They are supported by the mach64, r128, radeon drivers
>    */
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> index 2ddf5198e5c4..89f876cc60e6 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> @@ -1188,6 +1188,163 @@ static int smu_get_thermal_temperature_range(struct smu_context *smu)
>   	return ret;
>   }
>   
> +/**
> + * smu_wbrf_handle_exclusion_ranges - consume the wbrf exclusion ranges
> + *
> + * @smu: smu_context pointer
> + *
> + * Retrieve the wbrf exclusion ranges and send them to PMFW for proper handling.
> + * Returns 0 on success, error on failure.
> + */
> +static int smu_wbrf_handle_exclusion_ranges(struct smu_context *smu)
> +{
> +	struct wbrf_ranges_out wbrf_exclusion = {0};
> +	struct exclusion_range *wifi_bands = wbrf_exclusion.band_list;
> +	struct amdgpu_device *adev = smu->adev;
> +	uint64_t start, end;
> +	int ret, i, j;
> +
> +	ret = amdgpu_acpi_wbrf_retrieve_exclusions(adev, &wbrf_exclusion);
> +	if (ret) {
> +		dev_err(adev->dev, "Failed to retrieve exclusion ranges!\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * The exclusion ranges array we got might be filled with holes and duplicate
> +	 * entries. For example:
> +	 * {(2400, 2500), (0, 0), (6882, 6962), (2400, 2500), (0, 0), (6117, 6189), (0, 0)...}
> +	 * We need to do some sortups to eliminate those holes and duplicate entries.
> +	 * Expected output: {(2400, 2500), (6117, 6189), (6882, 6962), (0, 0)...}
> +	 */
> +	for (i = 0; i < MAX_NUM_OF_WBRF_RANGES; i++) {
> +		start = wifi_bands[i].start;
> +		end = wifi_bands[i].end;
> +
> +		/* get the last valid entry to fill the intermediate hole */
> +		if (!start && !end) {
> +			for (j = MAX_NUM_OF_WBRF_RANGES - 1; j > i; j--)
> +				if (wifi_bands[j].start &&
> +				    wifi_bands[j].end)
> +					break;
> +
> +			if (j > i) {
> +				wifi_bands[i].start = wifi_bands[j].start;
> +				wifi_bands[i].end = wifi_bands[j].end;
> +				wifi_bands[j].start = 0;
> +				wifi_bands[j].end = 0;
> +			}
> +
> +			continue;
> +		}
> +
> +		/* eliminate duplicate entries */
> +		for (j = i + 1; j < MAX_NUM_OF_WBRF_RANGES; j++) {
> +			if ((wifi_bands[j].start == start) &&
> +			     (wifi_bands[j].end == end)) {
> +				wifi_bands[j].start = 0;
> +				wifi_bands[j].end = 0;
> +				continue;
> +			}
> +		}
> +	}
> +
> +	/* Send the sorted wifi_bands to PMFW */
> +	ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);

Do we need to make sure to wake up the device (say if it's in BOCO) 
before calling this? Or, is it expected that the device gets active when 
these notifications come?

> +	/* Give it another chance */
> +	if (unlikely(ret == -EBUSY)) {
> +		mdelay(5);
> +		ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);
> +	}
> +
> +	return ret;
> +}
> +
> +/**
> + * smu_wbrf_event_handler - handle notify events
> + *
> + * @adev: struct amdgpu_device pointer
> + *
> + * Calls relevant amdgpu function in response to wbrf event
> + * notification from BIOS.
> + */
> +static void smu_wbrf_event_handler(struct amdgpu_device *adev)
> +{
> +	struct smu_context *smu = adev->powerplay.pp_handle;
> +
> +	smu_wbrf_handle_exclusion_ranges(smu);
> +}
> +
> +/**
> + * smu_wbrf_support_check - check wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Verifies the ACPI interface whether wbrf is supported.
> + */
> +static void smu_wbrf_support_check(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +
> +	smu->wbrf_supported = smu_is_asic_wbrf_supported(smu) &&
> +			      !!amdgpu_wbrf &&
> +			      amdgpu_acpi_is_wbrf_supported(adev);
> +
> +	if (smu->wbrf_supported)
> +		dev_info(adev->dev, "Enabled RF interference mitigations\n");

Minor comment - at this point nothing is enabled, it only detected 
hardware support. I guess, once FW is instructed to use shadow pstates 
only then mitigation steps are enabled.

Thanks,
Lijo

> +}
> +
> +/**
> + * smu_wbrf_init - init driver wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Verifies the AMD ACPI interfaces and registers with the wbrf
> + * notifier chain if wbrf feature is supported.
> + * Returns 0 on success, error on failure.
> + */
> +static int smu_wbrf_init(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +	int ret;
> +
> +	if (!smu->wbrf_supported)
> +		return 0;
> +
> +	ret = amdgpu_acpi_register_wbrf_notify_handler(adev,
> +						       smu_wbrf_event_handler);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * Some wifiband exclusion ranges may be already there
> +	 * before our driver loaded. To make sure our driver
> +	 * is awared of those exclusion ranges.
> +	 */
> +	ret = smu_wbrf_handle_exclusion_ranges(smu);
> +	if (ret)
> +		dev_err(adev->dev, "Failed to handle wbrf exclusion ranges\n");
> +
> +	return ret;
> +}
> +
> +/**
> + * smu_wbrf_fini - tear down driver wbrf support
> + *
> + * @smu: smu_context pointer
> + *
> + * Unregisters with the wbrf notifier chain.
> + */
> +static void smu_wbrf_fini(struct smu_context *smu)
> +{
> +	struct amdgpu_device *adev = smu->adev;
> +
> +	if (!smu->wbrf_supported)
> +		return;
> +
> +	amdgpu_acpi_unregister_wbrf_notify_handler(adev);
> +}
> +
>   static int smu_smc_hw_setup(struct smu_context *smu)
>   {
>   	struct smu_feature *feature = &smu->smu_feature;
> @@ -1280,6 +1437,15 @@ static int smu_smc_hw_setup(struct smu_context *smu)
>   	if (ret)
>   		return ret;
>   
> +	/* Enable UclkShadow on wbrf supported */
> +	if (smu->wbrf_supported) {
> +		ret = smu_enable_uclk_shadow(smu, true);
> +		if (ret) {
> +			dev_err(adev->dev, "Failed to enable UclkShadow feature to support wbrf!\n");
> +			return ret;
> +		}
> +	}
> +
>   	/*
>   	 * With SCPM enabled, these actions(and relevant messages) are
>   	 * not needed and permitted.
> @@ -1376,6 +1542,15 @@ static int smu_smc_hw_setup(struct smu_context *smu)
>   	 */
>   	ret = smu_set_min_dcef_deep_sleep(smu,
>   					  smu->smu_table.boot_values.dcefclk / 100);
> +	if (ret) {
> +		dev_err(adev->dev, "Error setting min deepsleep dcefclk\n");
> +		return ret;
> +	}
> +
> +	/* Init wbrf support. Properly setup the notifier */
> +	ret = smu_wbrf_init(smu);
> +	if (ret)
> +		dev_err(adev->dev, "Error during wbrf init call\n");
>   
>   	return ret;
>   }
> @@ -1431,6 +1606,13 @@ static int smu_hw_init(void *handle)
>   		return ret;
>   	}
>   
> +	/*
> +	 * Check whether wbrf is supported. This needs to be done
> +	 * before SMU setup starts since part of SMU configuration
> +	 * relies on this.
> +	 */
> +	smu_wbrf_support_check(smu);
> +
>   	if (smu->is_apu) {
>   		ret = smu_set_gfx_imu_enable(smu);
>   		if (ret)
> @@ -1583,6 +1765,8 @@ static int smu_smc_hw_cleanup(struct smu_context *smu)
>   	struct amdgpu_device *adev = smu->adev;
>   	int ret = 0;
>   
> +	smu_wbrf_fini(smu);
> +
>   	cancel_work_sync(&smu->throttling_logging_work);
>   	cancel_work_sync(&smu->interrupt_work);
>   
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> index 09469c750a96..ff0af3da0be2 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> +++ b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> @@ -573,6 +573,9 @@ struct smu_context
>   	u32 debug_param_reg;
>   	u32 debug_msg_reg;
>   	u32 debug_resp_reg;
> +
> +	/* data structures for wbrf feature support */
> +	bool				wbrf_supported;
>   };
>   
>   struct i2c_adapter;
> @@ -1354,6 +1357,23 @@ struct pptable_funcs {
>   	 * @init_pptable_microcode: Prepare the pptable microcode to upload via PSP
>   	 */
>   	int (*init_pptable_microcode)(struct smu_context *smu);
> +
> +	/**
> +	 * @is_asic_wbrf_supported: check whether PMFW supports the wbrf feature
> +	 */
> +	bool (*is_asic_wbrf_supported)(struct smu_context *smu);
> +
> +	/**
> +	 * @enable_uclk_shadow: Enable the uclk shadow feature on wbrf supported
> +	 */
> +	int (*enable_uclk_shadow)(struct smu_context *smu,
> +				  bool enablement);
> +
> +	/**
> +	 * @set_wbrf_exclusion_ranges: notify SMU the wifi bands occupied
> +	 */
> +	int (*set_wbrf_exclusion_ranges)(struct smu_context *smu,
> +					 struct exclusion_range *exclusion_ranges);
>   };
>   
>   typedef enum {
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> index ceb13c838067..67d7495ab49e 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> +++ b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> @@ -97,6 +97,9 @@
>   #define smu_get_default_config_table_settings(smu, config_table)	smu_ppt_funcs(get_default_config_table_settings, -EOPNOTSUPP, smu, config_table)
>   #define smu_set_config_table(smu, config_table)				smu_ppt_funcs(set_config_table, -EOPNOTSUPP, smu, config_table)
>   #define smu_init_pptable_microcode(smu)					smu_ppt_funcs(init_pptable_microcode, 0, smu)
> +#define smu_is_asic_wbrf_supported(smu)					smu_ppt_funcs(is_asic_wbrf_supported, false, smu)
> +#define smu_enable_uclk_shadow(smu, enablement)				smu_ppt_funcs(enable_uclk_shadow, 0, smu, enablement)
> +#define smu_set_wbrf_exclusion_ranges(smu, exclusion_ranges)		smu_ppt_funcs(set_wbrf_exclusion_ranges, -EOPNOTSUPP, smu, exclusion_ranges)
>   
>   #endif
>   #endif
  

[AMD Official Use Only - General]

> -----Original Message-----
> From: Lazar, Lijo <Lijo.Lazar@amd.com>
> Sent: Monday, June 19, 2023 10:55 PM
> To: Quan, Evan <Evan.Quan@amd.com>; rafael@kernel.org; lenb@kernel.org;
> Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian
> <Christian.Koenig@amd.com>; Pan, Xinhui <Xinhui.Pan@amd.com>;
> airlied@gmail.com; daniel@ffwll.ch; kvalo@kernel.org; nbd@nbd.name;
> lorenzo@kernel.org; ryder.lee@mediatek.com; shayne.chen@mediatek.com;
> sean.wang@mediatek.com; matthias.bgg@gmail.com;
> angelogioacchino.delregno@collabora.com; Limonciello, Mario
> <Mario.Limonciello@amd.com>
> Cc: linux-kernel@vger.kernel.org; linux-acpi@vger.kernel.org; amd-
> gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; linux-
> wireless@vger.kernel.org
> Subject: Re: [PATCH V3 4/7] drm/amd/pm: setup the framework to support
> Wifi RFI mitigation feature
>
>
>
> On 6/16/2023 12:27 PM, Evan Quan wrote:
> > With WBRF feature supported, as a driver responding to the
> > frequencies, amdgpu driver is able to do shadow pstate switching to
> > mitigate possible interference(between its (G-)DDR memory clocks and
> > local radio module frequency bands used by Wifi 6/6e/7).
> >
> > To make WBRF feature functional, the kernel needs to be configured
> > with CONFIG_ACPI_WBRF and the platform is equipped with necessary ACPI
> > based mechanism to get amdgpu driver notified.
> >
> > Signed-off-by: Evan Quan <evan.quan@amd.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  26 +++
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c      |  63 ++++++
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  19 ++
> >   drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     | 184
> ++++++++++++++++++
> >   drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h |  20 ++
> >   drivers/gpu/drm/amd/pm/swsmu/smu_internal.h   |   3 +
> >   6 files changed, 315 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > index 02b827785e39..2f2ec64ed1b2 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > @@ -50,6 +50,7 @@
> >   #include <linux/hashtable.h>
> >   #include <linux/dma-fence.h>
> >   #include <linux/pci.h>
> > +#include <linux/wbrf.h>
> >
> >   #include <drm/ttm/ttm_bo.h>
> >   #include <drm/ttm/ttm_placement.h>
> > @@ -241,6 +242,7 @@ extern int amdgpu_num_kcq;
> >   #define AMDGPU_VCNFW_LOG_SIZE (32 * 1024)
> >   extern int amdgpu_vcnfw_log;
> >   extern int amdgpu_sg_display;
> > +extern int amdgpu_wbrf;
> >
> >   #define AMDGPU_VM_MAX_NUM_CTX                     4096
> >   #define AMDGPU_SG_THRESHOLD                       (256*1024*1024)
> > @@ -741,6 +743,9 @@ struct amdgpu_reset_domain;
> >    */
> >   #define AMDGPU_HAS_VRAM(_adev) ((_adev)->gmc.real_vram_size)
> >
> > +typedef
> > +void (*wbrf_notify_handler) (struct amdgpu_device *adev);
> > +
> >   struct amdgpu_device {
> >     struct device                   *dev;
> >     struct pci_dev                  *pdev;
> > @@ -1050,6 +1055,8 @@ struct amdgpu_device {
> >
> >     bool                            job_hang;
> >     bool                            dc_enabled;
> > +
> > +   wbrf_notify_handler             wbrf_event_handler;
> >   };
> >
> >   static inline struct amdgpu_device *drm_to_adev(struct drm_device
> > *ddev) @@ -1381,6 +1388,25 @@ static inline int
> amdgpu_acpi_smart_shift_update(struct drm_device *dev,
> >                                              enum amdgpu_ss ss_state)
> { return 0; }
> >   #endif
> >
> > +#if defined(CONFIG_ACPI_WBRF)
> > +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev); int
> > +amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> > +                                    struct wbrf_ranges_out
> *exclusions_out); int
> > +amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device *adev,
> > +                                        wbrf_notify_handler handler); int
> > +amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device
> > +*adev); #else static inline bool amdgpu_acpi_is_wbrf_supported(struct
> > +amdgpu_device *adev) { return false; } static inline int
> > +amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> > +                                    struct wbrf_ranges_out
> *exclusions_out) { return 0; } static
> > +inline int amdgpu_acpi_register_wbrf_notify_handler(struct
> > +amdgpu_device *adev,
> > +                                        wbrf_notify_handler handler)
> { return 0; } static inline
> > +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device
> > +*adev) { return 0; } #endif
> > +
> >   #if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND)
> >   bool amdgpu_acpi_is_s3_active(struct amdgpu_device *adev);
> >   bool amdgpu_acpi_is_s0ix_active(struct amdgpu_device *adev); diff
> > --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> > index aeeec211861c..efbe6dd91d1a 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
> > @@ -1105,3 +1105,66 @@ bool amdgpu_acpi_is_s0ix_active(struct
> amdgpu_device *adev)
> >   }
> >
> >   #endif /* CONFIG_SUSPEND */
> > +
> > +#ifdef CONFIG_ACPI_WBRF
> > +bool amdgpu_acpi_is_wbrf_supported(struct amdgpu_device *adev) {
> > +   struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> > +
> > +   if (!acpi_dev)
> > +           return false;
> > +
> > +   return wbrf_supported_consumer(acpi_dev);
> > +}
> > +
> > +int amdgpu_acpi_wbrf_retrieve_exclusions(struct amdgpu_device *adev,
> > +                                    struct wbrf_ranges_out
> *exclusions_out) {
> > +   struct acpi_device *acpi_dev = ACPI_COMPANION(adev->dev);
> > +
> > +   if (!acpi_dev)
> > +           return -ENODEV;
> > +
> > +   return wbrf_retrieve_exclusions(acpi_dev, exclusions_out); }
> > +
> > +#define CPM_GPU_NOTIFY_COMMAND             0x55
> > +static void amdgpu_acpi_wbrf_event(acpi_handle handle, u32 event,
> > +void *data) {
> > +   struct amdgpu_device *adev = (struct amdgpu_device *)data;
> > +
> > +   if (event == CPM_GPU_NOTIFY_COMMAND &&
> > +       adev->wbrf_event_handler)
> > +           adev->wbrf_event_handler(adev); > +}
> > +
> > +int amdgpu_acpi_register_wbrf_notify_handler(struct amdgpu_device
> *adev,
> > +                                        wbrf_notify_handler handler) {
> > +   struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> > +
> > +   if (!acpi_hdler)
> > +           return -ENODEV;
> > +
> > +   adev->wbrf_event_handler = handler;
> > +
> > +   return acpi_install_notify_handler(acpi_hdler,
> > +                                      ACPI_ALL_NOTIFY,
> > +                                      amdgpu_acpi_wbrf_event,
> > +                                      adev);
> > +}
> > +
> > +int amdgpu_acpi_unregister_wbrf_notify_handler(struct amdgpu_device
> > +*adev) {
> > +   struct acpi_handle *acpi_hdler = ACPI_HANDLE(adev->dev);
> > +
> > +   if (!acpi_hdler)
> > +           return -ENODEV;
> > +
> > +   adev->wbrf_event_handler = NULL;
> > +
> > +   return acpi_remove_notify_handler(acpi_hdler,
> > +                                     ACPI_ALL_NOTIFY,
> > +                                     amdgpu_acpi_wbrf_event);
> > +}
> > +#endif
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > index b1ca1ab6d6ad..bf82cc192153 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > @@ -191,6 +191,7 @@ int amdgpu_smartshift_bias;
> >   int amdgpu_use_xgmi_p2p = 1;
> >   int amdgpu_vcnfw_log;
> >   int amdgpu_sg_display = -1; /* auto */
> > +int amdgpu_wbrf = -1;
> >
> >   static void amdgpu_drv_delayed_reset_work_handler(struct work_struct
> > *work);
> >
> > @@ -948,6 +949,24 @@ MODULE_PARM_DESC(smu_pptable_id,
> >     "specify pptable id to be used (-1 = auto(default) value, 0 = use
> pptable from vbios, > 0 = soft pptable id)");
> >   module_param_named(smu_pptable_id, amdgpu_smu_pptable_id, int,
> > 0444);
> >
> > +#ifdef CONFIG_ACPI_WBRF
> > +/**
> > + * DOC: wbrf (int)
> > + * Enable Wifi RFI interference mitigation feature.
> > + * Due to electrical and mechanical constraints there may be likely
> > +interference of
> > + * relatively high-powered harmonics of the (G-)DDR memory clocks
> > +with local radio
> > + * module frequency bands used by Wifi 6/6e/7. To mitigate the
> > +possible RFI interference,
> > + * with this feature enabled, PMFW will use either “shadowed P-State”
> > +or “P-State” based
> > + * on active list of frequencies in-use (to be avoided) as part of
> > +initial setting or
> > + * P-state transition. However, there may be potential performance
> > +impact with this
> > + * feature enabled.
> > + * (0 = disabled, 1 = enabled, -1 = auto (default setting, will be
> > +enabled if supported))  */ MODULE_PARM_DESC(wbrf,
> > +   "Enable Wifi RFI interference mitigation (0 = disabled, 1 = enabled,
> > +-1 = auto(default)"); module_param_named(wbrf, amdgpu_wbrf, int,
> > +0444); #endif
> > +
> >   /* These devices are not supported by amdgpu.
> >    * They are supported by the mach64, r128, radeon drivers
> >    */
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > index 2ddf5198e5c4..89f876cc60e6 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > @@ -1188,6 +1188,163 @@ static int
> smu_get_thermal_temperature_range(struct smu_context *smu)
> >     return ret;
> >   }
> >
> > +/**
> > + * smu_wbrf_handle_exclusion_ranges - consume the wbrf exclusion
> > +ranges
> > + *
> > + * @smu: smu_context pointer
> > + *
> > + * Retrieve the wbrf exclusion ranges and send them to PMFW for proper
> handling.
> > + * Returns 0 on success, error on failure.
> > + */
> > +static int smu_wbrf_handle_exclusion_ranges(struct smu_context *smu)
> > +{
> > +   struct wbrf_ranges_out wbrf_exclusion = {0};
> > +   struct exclusion_range *wifi_bands = wbrf_exclusion.band_list;
> > +   struct amdgpu_device *adev = smu->adev;
> > +   uint64_t start, end;
> > +   int ret, i, j;
> > +
> > +   ret = amdgpu_acpi_wbrf_retrieve_exclusions(adev, &wbrf_exclusion);
> > +   if (ret) {
> > +           dev_err(adev->dev, "Failed to retrieve exclusion ranges!\n");
> > +           return ret;
> > +   }
> > +
> > +   /*
> > +    * The exclusion ranges array we got might be filled with holes and
> duplicate
> > +    * entries. For example:
> > +    * {(2400, 2500), (0, 0), (6882, 6962), (2400, 2500), (0, 0), (6117,
> 6189), (0, 0)...}
> > +    * We need to do some sortups to eliminate those holes and duplicate
> entries.
> > +    * Expected output: {(2400, 2500), (6117, 6189), (6882, 6962), (0,
> 0)...}
> > +    */
> > +   for (i = 0; i < MAX_NUM_OF_WBRF_RANGES; i++) {
> > +           start = wifi_bands[i].start;
> > +           end = wifi_bands[i].end;
> > +
> > +           /* get the last valid entry to fill the intermediate hole */
> > +           if (!start && !end) {
> > +                   for (j = MAX_NUM_OF_WBRF_RANGES - 1; j > i; j--)
> > +                           if (wifi_bands[j].start &&
> > +                               wifi_bands[j].end)
> > +                                   break;
> > +
> > +                   if (j > i) {
> > +                           wifi_bands[i].start = wifi_bands[j].start;
> > +                           wifi_bands[i].end = wifi_bands[j].end;
> > +                           wifi_bands[j].start = 0;
> > +                           wifi_bands[j].end = 0;
> > +                   }
> > +
> > +                   continue;
> > +           }
> > +
> > +           /* eliminate duplicate entries */
> > +           for (j = i + 1; j < MAX_NUM_OF_WBRF_RANGES; j++) {
> > +                   if ((wifi_bands[j].start == start) &&
> > +                        (wifi_bands[j].end == end)) {
> > +                           wifi_bands[j].start = 0;
> > +                           wifi_bands[j].end = 0;
> > +                           continue;
> > +                   }
> > +           }
> > +   }
> > +
> > +   /* Send the sorted wifi_bands to PMFW */
> > +   ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);
>
> Do we need to make sure to wake up the device (say if it's in BOCO) before
> calling this? Or, is it expected that the device gets active when these
> notifications come?
None of them fits actually. There will be no notification coming for the graphics card once it was put into runpm suspended state.
However, on the device resuming, there is an intentional check for possible missing notifications. So, here it should be OK.
>
> > +   /* Give it another chance */
> > +   if (unlikely(ret == -EBUSY)) {
> > +           mdelay(5);
> > +           ret = smu_set_wbrf_exclusion_ranges(smu, wifi_bands);
> > +   }
> > +
> > +   return ret;
> > +}
> > +
> > +/**
> > + * smu_wbrf_event_handler - handle notify events
> > + *
> > + * @adev: struct amdgpu_device pointer
> > + *
> > + * Calls relevant amdgpu function in response to wbrf event
> > + * notification from BIOS.
> > + */
> > +static void smu_wbrf_event_handler(struct amdgpu_device *adev) {
> > +   struct smu_context *smu = adev->powerplay.pp_handle;
> > +
> > +   smu_wbrf_handle_exclusion_ranges(smu);
> > +}
> > +
> > +/**
> > + * smu_wbrf_support_check - check wbrf support
> > + *
> > + * @smu: smu_context pointer
> > + *
> > + * Verifies the ACPI interface whether wbrf is supported.
> > + */
> > +static void smu_wbrf_support_check(struct smu_context *smu) {
> > +   struct amdgpu_device *adev = smu->adev;
> > +
> > +   smu->wbrf_supported = smu_is_asic_wbrf_supported(smu) &&
> > +                         !!amdgpu_wbrf &&
> > +                         amdgpu_acpi_is_wbrf_supported(adev);
> > +
> > +   if (smu->wbrf_supported)
> > +           dev_info(adev->dev, "Enabled RF interference mitigations\n");
>
> Minor comment - at this point nothing is enabled, it only detected hardware
> support. I guess, once FW is instructed to use shadow pstates only then
> mitigation steps are enabled.
OK, I'm going to update this as "RF interference mitigation is supported".

Evan
>
> Thanks,
> Lijo
>
> > +}
> > +
> > +/**
> > + * smu_wbrf_init - init driver wbrf support
> > + *
> > + * @smu: smu_context pointer
> > + *
> > + * Verifies the AMD ACPI interfaces and registers with the wbrf
> > + * notifier chain if wbrf feature is supported.
> > + * Returns 0 on success, error on failure.
> > + */
> > +static int smu_wbrf_init(struct smu_context *smu) {
> > +   struct amdgpu_device *adev = smu->adev;
> > +   int ret;
> > +
> > +   if (!smu->wbrf_supported)
> > +           return 0;
> > +
> > +   ret = amdgpu_acpi_register_wbrf_notify_handler(adev,
> > +
> smu_wbrf_event_handler);
> > +   if (ret)
> > +           return ret;
> > +
> > +   /*
> > +    * Some wifiband exclusion ranges may be already there
> > +    * before our driver loaded. To make sure our driver
> > +    * is awared of those exclusion ranges.
> > +    */
> > +   ret = smu_wbrf_handle_exclusion_ranges(smu);
> > +   if (ret)
> > +           dev_err(adev->dev, "Failed to handle wbrf exclusion
> ranges\n");
> > +
> > +   return ret;
> > +}
> > +
> > +/**
> > + * smu_wbrf_fini - tear down driver wbrf support
> > + *
> > + * @smu: smu_context pointer
> > + *
> > + * Unregisters with the wbrf notifier chain.
> > + */
> > +static void smu_wbrf_fini(struct smu_context *smu) {
> > +   struct amdgpu_device *adev = smu->adev;
> > +
> > +   if (!smu->wbrf_supported)
> > +           return;
> > +
> > +   amdgpu_acpi_unregister_wbrf_notify_handler(adev);
> > +}
> > +
> >   static int smu_smc_hw_setup(struct smu_context *smu)
> >   {
> >     struct smu_feature *feature = &smu->smu_feature; @@ -1280,6
> > +1437,15 @@ static int smu_smc_hw_setup(struct smu_context *smu)
> >     if (ret)
> >             return ret;
> >
> > +   /* Enable UclkShadow on wbrf supported */
> > +   if (smu->wbrf_supported) {
> > +           ret = smu_enable_uclk_shadow(smu, true);
> > +           if (ret) {
> > +                   dev_err(adev->dev, "Failed to enable UclkShadow
> feature to support wbrf!\n");
> > +                   return ret;
> > +           }
> > +   }
> > +
> >     /*
> >      * With SCPM enabled, these actions(and relevant messages) are
> >      * not needed and permitted.
> > @@ -1376,6 +1542,15 @@ static int smu_smc_hw_setup(struct
> smu_context *smu)
> >      */
> >     ret = smu_set_min_dcef_deep_sleep(smu,
> >                                       smu->smu_table.boot_values.dcefclk
> / 100);
> > +   if (ret) {
> > +           dev_err(adev->dev, "Error setting min deepsleep dcefclk\n");
> > +           return ret;
> > +   }
> > +
> > +   /* Init wbrf support. Properly setup the notifier */
> > +   ret = smu_wbrf_init(smu);
> > +   if (ret)
> > +           dev_err(adev->dev, "Error during wbrf init call\n");
> >
> >     return ret;
> >   }
> > @@ -1431,6 +1606,13 @@ static int smu_hw_init(void *handle)
> >             return ret;
> >     }
> >
> > +   /*
> > +    * Check whether wbrf is supported. This needs to be done
> > +    * before SMU setup starts since part of SMU configuration
> > +    * relies on this.
> > +    */
> > +   smu_wbrf_support_check(smu);
> > +
> >     if (smu->is_apu) {
> >             ret = smu_set_gfx_imu_enable(smu);
> >             if (ret)
> > @@ -1583,6 +1765,8 @@ static int smu_smc_hw_cleanup(struct
> smu_context *smu)
> >     struct amdgpu_device *adev = smu->adev;
> >     int ret = 0;
> >
> > +   smu_wbrf_fini(smu);
> > +
> >     cancel_work_sync(&smu->throttling_logging_work);
> >     cancel_work_sync(&smu->interrupt_work);
> >
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> > b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> > index 09469c750a96..ff0af3da0be2 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> > @@ -573,6 +573,9 @@ struct smu_context
> >     u32 debug_param_reg;
> >     u32 debug_msg_reg;
> >     u32 debug_resp_reg;
> > +
> > +   /* data structures for wbrf feature support */
> > +   bool                            wbrf_supported;
> >   };
> >
> >   struct i2c_adapter;
> > @@ -1354,6 +1357,23 @@ struct pptable_funcs {
> >      * @init_pptable_microcode: Prepare the pptable microcode to upload
> via PSP
> >      */
> >     int (*init_pptable_microcode)(struct smu_context *smu);
> > +
> > +   /**
> > +    * @is_asic_wbrf_supported: check whether PMFW supports the wbrf
> feature
> > +    */
> > +   bool (*is_asic_wbrf_supported)(struct smu_context *smu);
> > +
> > +   /**
> > +    * @enable_uclk_shadow: Enable the uclk shadow feature on wbrf
> supported
> > +    */
> > +   int (*enable_uclk_shadow)(struct smu_context *smu,
> > +                             bool enablement);
> > +
> > +   /**
> > +    * @set_wbrf_exclusion_ranges: notify SMU the wifi bands occupied
> > +    */
> > +   int (*set_wbrf_exclusion_ranges)(struct smu_context *smu,
> > +                                    struct exclusion_range
> *exclusion_ranges);
> >   };
> >
> >   typedef enum {
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> > b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> > index ceb13c838067..67d7495ab49e 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/smu_internal.h
> > @@ -97,6 +97,9 @@
> >   #define smu_get_default_config_table_settings(smu, config_table)
>       smu_ppt_funcs(get_default_config_table_settings, -EOPNOTSUPP,
> smu, config_table)
> >   #define smu_set_config_table(smu, config_table)
>       smu_ppt_funcs(set_config_table, -EOPNOTSUPP, smu, config_table)
> >   #define smu_init_pptable_microcode(smu)
>       smu_ppt_funcs(init_pptable_microcode, 0, smu)
> > +#define smu_is_asic_wbrf_supported(smu)
>       smu_ppt_funcs(is_asic_wbrf_supported, false, smu)
> > +#define smu_enable_uclk_shadow(smu, enablement)
>               smu_ppt_funcs(enable_uclk_shadow, 0, smu, enablement)
> > +#define smu_set_wbrf_exclusion_ranges(smu, exclusion_ranges)
>       smu_ppt_funcs(set_wbrf_exclusion_ranges, -EOPNOTSUPP, smu,
> exclusion_ranges)
> >
> >   #endif
> >   #endif