Re: [Intel-gfx] [PATCH v2 03/12] drm/i915/pvc: Define MOCS table for PVC

On Thu, May 05, 2022 at 02:38:03PM -0700, Matt Roper wrote:

From: Ayaz A Siddiqui ayaz.siddiqui@intel.com

v2 (MattR):

• Clarify comment above RING_CMD_CCTL programming.
• Remove bspec reference from field definition. (Lucas)
• Add WARN if we try to use a (presumably uninitialized) wb_index of 0. On most platforms 0 is an invalid MOCS entry and even on the ones where it isn't, it isn't the right setting for wb_index. (Lucas)

Bspec: 45101, 72161 Cc: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Ayaz A Siddiqui ayaz.siddiqui@intel.com Signed-off-by: Fei Yang fei.yang@intel.com Signed-off-by: Matt Roper matthew.d.roper@intel.com

---

drivers/gpu/drm/i915/gt/intel_gt_types.h | 1 + drivers/gpu/drm/i915/gt/intel_mocs.c | 24 ++++++++++++++++- drivers/gpu/drm/i915/gt/intel_workarounds.c | 30 ++++++++++++++++----- drivers/gpu/drm/i915/i915_drv.h | 2 ++ drivers/gpu/drm/i915/i915_pci.c | 3 ++- drivers/gpu/drm/i915/intel_device_info.h | 1 + 6 files changed, 53 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_types.h b/drivers/gpu/drm/i915/gt/intel_gt_types.h index b06611c1d4ad..7853ea194ea6 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_types.h +++ b/drivers/gpu/drm/i915/gt/intel_gt_types.h @@ -221,6 +221,7 @@ struct intel_gt {

struct { u8 uc_index;

• u8 wb_index; /* Only for platforms listed in Bspec: 72161 */
  

doesn't correspond to changelog

other than that, Reviewed-by: Lucas De Marchi lucas.demarchi@intel.com

Lucas De Marchi

} mocs;

struct intel_pxp pxp; diff --git a/drivers/gpu/drm/i915/gt/intel_mocs.c b/drivers/gpu/drm/i915/gt/intel_mocs.c index c4c37585ae8c..c6ebe2781076 100644 --- a/drivers/gpu/drm/i915/gt/intel_mocs.c +++ b/drivers/gpu/drm/i915/gt/intel_mocs.c @@ -23,6 +23,7 @@ struct drm_i915_mocs_table { unsigned int n_entries; const struct drm_i915_mocs_entry *table; u8 uc_index;

• u8 wb_index; /* Only used on HAS_L3_CCS_READ() platforms */ u8 unused_entries_index;

};

@@ -47,6 +48,7 @@ struct drm_i915_mocs_table {

/* Helper defines */ #define GEN9_NUM_MOCS_ENTRIES 64 /* 63-64 are reserved, but configured. */ +#define PVC_NUM_MOCS_ENTRIES 3

/* (e)LLC caching options */ /* @@ -394,6 +396,17 @@ static const struct drm_i915_mocs_entry dg2_mocs_table_g10_ax[] = { MOCS_ENTRY(3, 0, L3_3_WB | L3_LKUP(1)), };

+static const struct drm_i915_mocs_entry pvc_mocs_table[] = {

• /* Error */
• MOCS_ENTRY(0, 0, L3_3_WB),
• /* UC */
• MOCS_ENTRY(1, 0, L3_1_UC),
• /* WB */
• MOCS_ENTRY(2, 0, L3_3_WB),

+};

enum { HAS_GLOBAL_MOCS = BIT(0), HAS_ENGINE_MOCS = BIT(1), @@ -423,7 +436,14 @@ static unsigned int get_mocs_settings(const struct drm_i915_private *i915, memset(table, 0, sizeof(struct drm_i915_mocs_table));

table->unused_entries_index = I915_MOCS_PTE;

• if (IS_DG2(i915)) {

• if (IS_PONTEVECCHIO(i915)) {

• table->size = ARRAY_SIZE(pvc_mocs_table);
  

• table->table = pvc_mocs_table;
  

• table->n_entries = PVC_NUM_MOCS_ENTRIES;
  

• table->uc_index = 1;
  

• table->wb_index = 2;
  

• table->unused_entries_index = 2;
  

• } else if (IS_DG2(i915)) { if (IS_DG2_GRAPHICS_STEP(i915, G10, STEP_A0, STEP_B0)) { table->size = ARRAY_SIZE(dg2_mocs_table_g10_ax); table->table = dg2_mocs_table_g10_ax;

@@ -622,6 +642,8 @@ void intel_set_mocs_index(struct intel_gt *gt)

get_mocs_settings(gt->i915, &table); gt->mocs.uc_index = table.uc_index;

• if (HAS_L3_CCS_READ(gt->i915))

• gt->mocs.wb_index = table.wb_index;
  

}

void intel_mocs_init(struct intel_gt *gt) diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c index a05c4b99b3fb..756807c4b405 100644 --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c @@ -1994,19 +1994,37 @@ void intel_engine_apply_whitelist(struct intel_engine_cs *engine) static void engine_fake_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal) {

• u8 mocs;

• u8 mocs_w, mocs_r;

  /*

• * RING_CMD_CCTL are need to be programed to un-cached
  

• * for memory writes and reads outputted by Command
  

• * Streamers on Gen12 onward platforms.
  

• * RING_CMD_CCTL specifies the default MOCS entry that will be used
  

• * by the command streamer when executing commands that don't have
  

• * a way to explicitly specify a MOCS setting.  The default should
  

• * usually reference whichever MOCS entry corresponds to uncached
  

• * behavior, although use of a WB cached entry is recommended by the
  

• * spec in certain circumstances on specific platforms.
  

  */ if (GRAPHICS_VER(engine->i915) >= 12) {

• mocs = engine->gt->mocs.uc_index;
  

• mocs_r = engine->gt->mocs.uc_index;
  

• mocs_w = engine->gt->mocs.uc_index;
  

• if (HAS_L3_CCS_READ(engine->i915) &&
  

•     engine->class == COMPUTE_CLASS) {
  

• 	mocs_r = engine->gt->mocs.wb_index;
  

• 	/*
  

• 	 * Even on the few platforms where MOCS 0 is a
  

• 	 * legitimate table entry, it's never the correct
  

• 	 * setting to use here; we can assume the MOCS init
  

• 	 * just forgot to initialize wb_index.
  

• 	 */
  

• 	drm_WARN_ON(&engine->i915->drm, mocs_r == 0);
  

• }
  

• wa_masked_field_set(wal, RING_CMD_CCTL(engine->mmio_base), CMD_CCTL_MOCS_MASK,

• 		    CMD_CCTL_MOCS_OVERRIDE(mocs, mocs));
  

• 		    CMD_CCTL_MOCS_OVERRIDE(mocs_w, mocs_r));
  

  }

}

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 00d7eeae33bd..b389674b5210 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1370,6 +1370,8 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,

#define HAS_LSPCON(dev_priv) (IS_DISPLAY_VER(dev_priv, 9, 10))

+#define HAS_L3_CCS_READ(i915) (INTEL_INFO(i915)->has_l3_ccs_read)

/* DPF == dynamic parity feature */ #define HAS_L3_DPF(dev_priv) (INTEL_INFO(dev_priv)->has_l3_dpf) #define NUM_L3_SLICES(dev_priv) (IS_HSW_GT3(dev_priv) ? \ diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c index 498708b33924..07722cdf63ac 100644 --- a/drivers/gpu/drm/i915/i915_pci.c +++ b/drivers/gpu/drm/i915/i915_pci.c @@ -1076,7 +1076,8 @@ static const struct intel_device_info ats_m_info = {

#define XE_HPC_FEATURES \ XE_HP_FEATURES, \

• .dma_mask_size = 52

• .dma_mask_size = 52, \
• .has_l3_ccs_read = 1

__maybe_unused static const struct intel_device_info pvc_info = { diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h index e7d2cf7d65c8..09e33296157a 100644 --- a/drivers/gpu/drm/i915/intel_device_info.h +++ b/drivers/gpu/drm/i915/intel_device_info.h @@ -150,6 +150,7 @@ enum intel_ppgtt_type { func(has_heci_pxp); \ func(has_heci_gscfi); \ func(has_guc_deprivilege); \

• func(has_l3_ccs_read); \ func(has_l3_dpf); \ func(has_llc); \ func(has_logical_ring_contexts); \

-- 2.35.1