[PATCH 6/9] drm/amd/pm: setup the framework to support Wifi RFI mitigation feature

From: Evan Quan
Date: Mon May 29 2023 - 22:44:42 EST

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@xxxxxxx>
--
v1->v2:
- move the implementations to swsmu(Lijo)
- support runpm suspend/resume scenario(Lijo)
- add missing mutex_destory(Mario)
v2->v3:
- Per the latest designs, get those ACPI interfaces
needed by consumer(VGA) implemented in amdgpu_smu.c
v3->v4:
- update the descriptions for parameter 'wbrf'(Alex)
v4->v5:
- support CONFIG_ACPI_WBRF disabled scenario
- correct the default setting for parameter `wbrf` as -1 (auto)(Alex)
v5->v6:
- separate those ACPI related code into amdgpu_acpi.c
and acpi_wbrf.c
v6->v7:
- wrap the document and modinfo for `wbrf` under
CONFIG_ACPI_WBRF(Mario)
v7->v8:
- some minor fixes around error/information prompts(Mario)
---
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
--
2.34.1