Re: [PATCH v2 6/9] drm/i915/dgfx: Setup VRAM SR with D3COLD

On Thu, 16 Jun 2022, Anshuman Gupta anshuman.gupta@intel.com wrote:

Setup VRAM Self Refresh with D3COLD state. VRAM Self Refresh will retain the context of VRAM, driver need to save any corresponding hardware state that needs to be restore on D3COLD exit, example PCI state.

Cc: Jani Nikula jani.nikula@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Anshuman Gupta anshuman.gupta@intel.com

---

drivers/gpu/drm/i915/i915_driver.c | 2 ++ drivers/gpu/drm/i915/i915_drv.h | 7 +++++ drivers/gpu/drm/i915/i915_reg.h | 4 +++ drivers/gpu/drm/i915/intel_pcode.c | 28 +++++++++++++++++++ drivers/gpu/drm/i915/intel_pcode.h | 2 ++ drivers/gpu/drm/i915/intel_pm.c | 43 ++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_pm.h | 2 ++ 7 files changed, 88 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c index d26dcca7e654..aa1fb15b1f11 100644 --- a/drivers/gpu/drm/i915/i915_driver.c +++ b/drivers/gpu/drm/i915/i915_driver.c @@ -649,6 +649,8 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv) if (ret) goto err_msi;

• intel_pm_vram_sr_setup(dev_priv);
• /*
  • Fill the dram structure to get the system dram info. This will be
  • used for memory latency calculation.

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 7983b36c1720..09f53aeda8d0 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -624,6 +624,13 @@ struct drm_i915_private { u32 bxt_phy_grc;

u32 suspend_count;

• struct {

• /* lock to protect vram_sr flags */
  

• struct mutex lock;
  

• bool supported;
  

• } vram_sr;
• struct i915_suspend_saved_registers regfile; struct vlv_s0ix_state *vlv_s0ix_state;

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 932bd6aa4a0a..0e3dc4a8846a 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -6766,6 +6766,8 @@ #define DG1_PCODE_STATUS 0x7E #define DG1_UNCORE_GET_INIT_STATUS 0x0 #define DG1_UNCORE_INIT_STATUS_COMPLETE 0x1 +#define DG1_PCODE_D3_VRAM_SR 0x71 +#define DG1_ENABLE_SR 0x1 #define GEN12_PCODE_READ_SAGV_BLOCK_TIME_US 0x23 #define XEHPSDV_PCODE_FREQUENCY_CONFIG 0x6e /* xehpsdv, pvc */ /* XEHPSDV_PCODE_FREQUENCY_CONFIG sub-commands (param1) */ @@ -6779,6 +6781,8 @@ #define GEN6_PCODE_FREQ_IA_RATIO_SHIFT 8 #define GEN6_PCODE_FREQ_RING_RATIO_SHIFT 16 #define GEN6_PCODE_DATA1 _MMIO(0x13812C) +#define VRAM_CAPABILITY _MMIO(0x138144) +#define VRAM_SUPPORTED REG_BIT(0)

/* IVYBRIDGE DPF */ #define GEN7_L3CDERRST1(slice) _MMIO(0xB008 + (slice) * 0x200) /* L3CD Error Status 1 */ diff --git a/drivers/gpu/drm/i915/intel_pcode.c b/drivers/gpu/drm/i915/intel_pcode.c index a234d9b4ed14..88bd1f44cfb2 100644 --- a/drivers/gpu/drm/i915/intel_pcode.c +++ b/drivers/gpu/drm/i915/intel_pcode.c @@ -246,3 +246,31 @@ int snb_pcode_write_p(struct intel_uncore *uncore, u32 mbcmd, u32 p1, u32 p2, u3

return err; }

+/**

• • intel_pcode_enable_vram_sr - Enable pcode vram_sr.
• • @dev_priv: i915 device
• • This function triggers the required pcode flow to enable vram_sr.
• • This function stictly need to call from rpm handlers, as i915 is
• • transitioning to rpm idle/suspend, it doesn't require to grab
• • rpm wakeref.
• • Returns:
• • returns returned value from pcode mbox write.
• */

+int intel_pcode_enable_vram_sr(struct drm_i915_private *i915) +{

• int ret = 0;
• if (!HAS_LMEM_SR(i915))

• return ret;
  

• ret = snb_pcode_write(&i915->uncore,

• 	      REG_FIELD_PREP(GEN6_PCODE_MB_COMMAND,
  

• 	      DG1_PCODE_D3_VRAM_SR) |
  

• 	      REG_FIELD_PREP(GEN6_PCODE_MB_PARAM1,
  

• 	      DG1_ENABLE_SR), 0); /* no data needed for this cmd */
  

• return ret;

+}

This function doesn't belong here. intel_pcode.c provides the *mechanisms* for pcode access, not specific stuff like this. Just put this near the use in intel_pm.c I think.

diff --git a/drivers/gpu/drm/i915/intel_pcode.h b/drivers/gpu/drm/i915/intel_pcode.h index 8d2198e29422..295594514d49 100644 --- a/drivers/gpu/drm/i915/intel_pcode.h +++ b/drivers/gpu/drm/i915/intel_pcode.h @@ -9,6 +9,7 @@ #include <linux/types.h>

struct intel_uncore; +struct drm_i915_private;

int snb_pcode_read(struct intel_uncore *uncore, u32 mbox, u32 *val, u32 *val1); int snb_pcode_write_timeout(struct intel_uncore *uncore, u32 mbox, u32 val, @@ -26,5 +27,6 @@ int intel_pcode_init(struct intel_uncore *uncore); */ int snb_pcode_read_p(struct intel_uncore *uncore, u32 mbcmd, u32 p1, u32 p2, u32 *val); int snb_pcode_write_p(struct intel_uncore *uncore, u32 mbcmd, u32 p1, u32 p2, u32 val); +int intel_pcode_enable_vram_sr(struct drm_i915_private *i915);

#endif /* _INTEL_PCODE_H */ diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 5a61fc3f26c1..299fbc5375a9 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -8166,6 +8166,49 @@ void intel_pm_setup(struct drm_i915_private *dev_priv) atomic_set(&dev_priv->runtime_pm.wakeref_count, 0); }

+void intel_pm_vram_sr_setup(struct drm_i915_private *i915) +{

• if (!HAS_LMEM_SR(i915))

• return;
  

• mutex_init(&i915->vram_sr.lock);
• i915->vram_sr.supported = intel_uncore_read(&i915->uncore,

• 				    VRAM_CAPABILITY) & VRAM_SUPPORTED;
  

• if (intel_opregion_vram_sr_required(i915))

• i915->vram_sr.supported = i915->vram_sr.supported &&
  

• 				intel_opregion_bios_supports_vram_sr(i915);
  

+}

+int intel_pm_vram_sr(struct drm_i915_private *i915, bool enable) +{

• int ret = 0;
• if (!HAS_LMEM_SR(i915))

• return -EOPNOTSUPP;
  

You can drop this and only look at i915->vram_sr.supported.

• mutex_lock(&i915->vram_sr.lock);
• if (!i915->vram_sr.supported) {

• drm_dbg(&i915->drm, "VRAM Self Refresh is not supported\n");
  

• ret = -EOPNOTSUPP;
  

• goto unlock;
  

• }

This part doesn't need the mutex protection. You don't actually change i915->vram_sr.supported anywhere after initialization.

• drm_dbg(&i915->drm, "VRAM Self Refresh supported\n");
• if (enable)

• ret = intel_pcode_enable_vram_sr(i915);
  

• if (ret)

• goto unlock;
  

• intel_opregion_vram_sr(i915, enable);

+unlock:

• mutex_unlock(&i915->vram_sr.lock);
• return ret;

+}

static struct intel_global_state *intel_dbuf_duplicate_state(struct intel_global_obj *obj) { struct intel_dbuf_state *dbuf_state; diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h index 50604cf7398c..0da85d6b9ea7 100644 --- a/drivers/gpu/drm/i915/intel_pm.h +++ b/drivers/gpu/drm/i915/intel_pm.h @@ -31,6 +31,8 @@ int ilk_wm_max_level(const struct drm_i915_private *dev_priv); void intel_init_pm(struct drm_i915_private *dev_priv); void intel_init_clock_gating_hooks(struct drm_i915_private *dev_priv); void intel_pm_setup(struct drm_i915_private *dev_priv); +void intel_pm_vram_sr_setup(struct drm_i915_private *i915); +int intel_pm_vram_sr(struct drm_i915_private *i915, bool enable); void g4x_wm_get_hw_state(struct drm_i915_private *dev_priv); void vlv_wm_get_hw_state(struct drm_i915_private *dev_priv); void ilk_wm_get_hw_state(struct drm_i915_private *dev_priv);