[Intel-gfx] [PATCH 15/33] drm/i915/guc: Provide mmio list to be saved/restored on engine reset

Matthew Brost
2021-07-22T23:37:06Z

From: "Signed-off-by: John Harrison" <John.C.Harrison@Intel.com>

The driver must provide GuC with a list of mmio registers
that should be saved/restored during a GuC-based engine reset.
Unfortunately, the list must be dynamically allocated as its size is
variable. That means the driver must generate the list twice - once to
work out the size and a second time to actually save it.

v2:
(Alan / CI)
- GEN7_GT_MODE -> GEN6_GT_MODE to fix WA selftest failure

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Fernando Pacheco <fernando.pacheco@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
---
drivers/gpu/drm/i915/gt/intel_workarounds.c | 46 ++--
.../gpu/drm/i915/gt/intel_workarounds_types.h | 1 +
drivers/gpu/drm/i915/gt/uc/intel_guc.h | 1 +
drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c | 199 +++++++++++++++++-
drivers/gpu/drm/i915/i915_reg.h | 1 +
5 files changed, 222 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 247f0331ebee..e2cdc181b623 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -150,13 +150,14 @@ static void _wa_add(struct i915_wa_list *wal, const struct i915_wa *wa)
}

static void wa_add(struct i915_wa_list *wal, i915_reg_t reg,
- u32 clear, u32 set, u32 read_mask)
+ u32 clear, u32 set, u32 read_mask, bool masked_reg)
{
struct i915_wa wa = {
.reg = reg,
.clr = clear,
.set = set,
.read = read_mask,
+ .masked_reg = masked_reg,
};

_wa_add(wal, &wa);
@@ -165,7 +166,7 @@ static void wa_add(struct i915_wa_list *wal, i915_reg_t reg,
static void
wa_write_clr_set(struct i915_wa_list *wal, i915_reg_t reg, u32 clear, u32 set)
{
- wa_add(wal, reg, clear, set, clear);
+ wa_add(wal, reg, clear, set, clear, false);
}

static void
@@ -200,20 +201,20 @@ wa_write_clr(struct i915_wa_list *wal, i915_reg_t reg, u32 clr)
static void
wa_masked_en(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
{
- wa_add(wal, reg, 0, _MASKED_BIT_ENABLE(val), val);
+ wa_add(wal, reg, 0, _MASKED_BIT_ENABLE(val), val, true);
}

static void
wa_masked_dis(struct i915_wa_list *wal, i915_reg_t reg, u32 val)
{
- wa_add(wal, reg, 0, _MASKED_BIT_DISABLE(val), val);
+ wa_add(wal, reg, 0, _MASKED_BIT_DISABLE(val), val, true);
}

static void
wa_masked_field_set(struct i915_wa_list *wal, i915_reg_t reg,
u32 mask, u32 val)
{
- wa_add(wal, reg, 0, _MASKED_FIELD(mask, val), mask);
+ wa_add(wal, reg, 0, _MASKED_FIELD(mask, val), mask, true);
}

static void gen6_ctx_workarounds_init(struct intel_engine_cs *engine,
@@ -533,10 +534,10 @@ static void icl_ctx_workarounds_init(struct intel_engine_cs *engine,
wa_masked_en(wal, ICL_HDC_MODE, HDC_FORCE_NON_COHERENT);

/* WaEnableFloatBlendOptimization:icl */
- wa_write_clr_set(wal,
- GEN10_CACHE_MODE_SS,
- 0, /* write-only, so skip validation */
- _MASKED_BIT_ENABLE(FLOAT_BLEND_OPTIMIZATION_ENABLE));
+ wa_add(wal, GEN10_CACHE_MODE_SS, 0,
+ _MASKED_BIT_ENABLE(FLOAT_BLEND_OPTIMIZATION_ENABLE),
+ 0 /* write-only, so skip validation */,
+ true);

/* WaDisableGPGPUMidThreadPreemption:icl */
wa_masked_field_set(wal, GEN8_CS_CHICKEN1,
@@ -581,7 +582,7 @@ static void gen12_ctx_gt_tuning_init(struct intel_engine_cs *engine,
FF_MODE2,
FF_MODE2_TDS_TIMER_MASK,
FF_MODE2_TDS_TIMER_128,
- 0);
+ 0, false);
}

static void gen12_ctx_workarounds_init(struct intel_engine_cs *engine,
@@ -619,7 +620,7 @@ static void gen12_ctx_workarounds_init(struct intel_engine_cs *engine,
FF_MODE2,
FF_MODE2_GS_TIMER_MASK,
FF_MODE2_GS_TIMER_224,
- 0);
+ 0, false);

/*
* Wa_14012131227:dg1
@@ -795,7 +796,7 @@ hsw_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
wa_add(wal,
HSW_ROW_CHICKEN3, 0,
_MASKED_BIT_ENABLE(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE),
- 0 /* XXX does this reg exist? */);
+ 0 /* XXX does this reg exist? */, true);

/* WaVSRefCountFullforceMissDisable:hsw */
wa_write_clr(wal, GEN7_FF_THREAD_MODE, GEN7_FF_VS_REF_CNT_FFME);
@@ -1824,10 +1825,10 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
* disable bit, which we don't touch here, but it's good
* to keep in mind (see 3DSTATE_PS and 3DSTATE_WM).
*/
- wa_add(wal, GEN7_GT_MODE, 0,
- _MASKED_FIELD(GEN6_WIZ_HASHING_MASK,
- GEN6_WIZ_HASHING_16x4),
- GEN6_WIZ_HASHING_16x4);
+ wa_masked_field_set(wal,
+ GEN7_GT_MODE,
+ GEN6_WIZ_HASHING_MASK,
+ GEN6_WIZ_HASHING_16x4);
}

if (IS_GRAPHICS_VER(i915, 6, 7))
@@ -1877,10 +1878,10 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
* disable bit, which we don't touch here, but it's good
* to keep in mind (see 3DSTATE_PS and 3DSTATE_WM).
*/
- wa_add(wal,
- GEN6_GT_MODE, 0,
- _MASKED_FIELD(GEN6_WIZ_HASHING_MASK, GEN6_WIZ_HASHING_16x4),
- GEN6_WIZ_HASHING_16x4);
+ wa_masked_field_set(wal,
+ GEN6_GT_MODE,
+ GEN6_WIZ_HASHING_MASK,
+ GEN6_WIZ_HASHING_16x4);

/* WaDisable_RenderCache_OperationalFlush:snb */
wa_masked_dis(wal, CACHE_MODE_0, RC_OP_FLUSH_ENABLE);
@@ -1901,7 +1902,7 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
wa_add(wal, MI_MODE,
0, _MASKED_BIT_ENABLE(VS_TIMER_DISPATCH),
/* XXX bit doesn't stick on Broadwater */
- IS_I965G(i915) ? 0 : VS_TIMER_DISPATCH);
+ IS_I965G(i915) ? 0 : VS_TIMER_DISPATCH, true);

if (GRAPHICS_VER(i915) == 4)
/*
@@ -1916,7 +1917,8 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
*/
wa_add(wal, ECOSKPD,
0, _MASKED_BIT_ENABLE(ECO_CONSTANT_BUFFER_SR_DISABLE),
- 0 /* XXX bit doesn't stick on Broadwater */);
+ 0 /* XXX bit doesn't stick on Broadwater */,
+ true);
}

static void
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds_types.h b/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
index c214111ea367..1e873681795d 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds_types.h
@@ -15,6 +15,7 @@ struct i915_wa {
u32 clr;
u32 set;
u32 read;
+ bool masked_reg;
};

struct i915_wa_list {
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
index 9c8d53a32e0d..f3c69160cb7e 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
@@ -59,6 +59,7 @@ struct intel_guc {

struct i915_vma *ads_vma;
struct __guc_ads_blob *ads_blob;
+ u32 ads_regset_size;

struct i915_vma *lrc_desc_pool;
void *lrc_desc_pool_vaddr;
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
index b82145652d57..9fd3c911f5fb 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
@@ -3,6 +3,8 @@
* Copyright © 2014-2019 Intel Corporation
*/

+#include <linux/bsearch.h>
+
#include "gt/intel_gt.h"
#include "gt/intel_lrc.h"
#include "intel_guc_ads.h"
@@ -23,7 +25,12 @@
* | guc_policies |
* +---------------------------------------+
* | guc_gt_system_info |
- * +---------------------------------------+
+ * +---------------------------------------+ <== static
+ * | guc_mmio_reg[countA] (engine 0.0) |
+ * | guc_mmio_reg[countB] (engine 0.1) |
+ * | guc_mmio_reg[countC] (engine 1.0) |
+ * | ... |
+ * +---------------------------------------+ <== dynamic
* | padding |
* +---------------------------------------+ <== 4K aligned
* | private data |
@@ -35,16 +42,33 @@ struct __guc_ads_blob {
struct guc_ads ads;
struct guc_policies policies;
struct guc_gt_system_info system_info;
+ /* From here on, location is dynamic! Refer to above diagram. */
+ struct guc_mmio_reg regset[0];
} __packed;

+static u32 guc_ads_regset_size(struct intel_guc *guc)
+{
+ GEM_BUG_ON(!guc->ads_regset_size);
+ return guc->ads_regset_size;
+}
+
static u32 guc_ads_private_data_size(struct intel_guc *guc)
{
return PAGE_ALIGN(guc->fw.private_data_size);
}

+static u32 guc_ads_regset_offset(struct intel_guc *guc)
+{
+ return offsetof(struct __guc_ads_blob, regset);
+}
+
static u32 guc_ads_private_data_offset(struct intel_guc *guc)
{
- return PAGE_ALIGN(sizeof(struct __guc_ads_blob));
+ u32 offset;
+
+ offset = guc_ads_regset_offset(guc) +
+ guc_ads_regset_size(guc);
+ return PAGE_ALIGN(offset);
}

static u32 guc_ads_blob_size(struct intel_guc *guc)
@@ -83,6 +107,165 @@ static void guc_mapping_table_init(struct intel_gt *gt,
}
}

+/*
+ * The save/restore register list must be pre-calculated to a temporary
+ * buffer of driver defined size before it can be generated in place
+ * inside the ADS.
+ */
+#define MAX_MMIO_REGS 128 /* Arbitrary size, increase as needed */
+struct temp_regset {
+ struct guc_mmio_reg *registers;
+ u32 used;
+ u32 size;
+};
+
+static int guc_mmio_reg_cmp(const void *a, const void *b)
+{
+ const struct guc_mmio_reg *ra = a;
+ const struct guc_mmio_reg *rb = b;
+
+ return (int)ra->offset - (int)rb->offset;
+}
+
+static void guc_mmio_reg_add(struct temp_regset *regset,
+ u32 offset, u32 flags)
+{
+ u32 count = regset->used;
+ struct guc_mmio_reg reg = {
+ .offset = offset,
+ .flags = flags,
+ };
+ struct guc_mmio_reg *slot;
+
+ GEM_BUG_ON(count >= regset->size);
+
+ /*
+ * The mmio list is built using separate lists within the driver.
+ * It's possible that at some point we may attempt to add the same
+ * register more than once. Do not consider this an error; silently
+ * move on if the register is already in the list.
+ */
+ if (bsearch(&reg, regset->registers, count,
+ sizeof(reg), guc_mmio_reg_cmp))
+ return;
+
+ slot = &regset->registers[count];
+ regset->used++;
+ *slot = reg;
+
+ while (slot-- > regset->registers) {
+ GEM_BUG_ON(slot[0].offset == slot[1].offset);
+ if (slot[1].offset > slot[0].offset)
+ break;
+
+ swap(slot[1], slot[0]);
+ }
+}
+
+#define GUC_MMIO_REG_ADD(regset, reg, masked) \
+ guc_mmio_reg_add(regset, \
+ i915_mmio_reg_offset((reg)), \
+ (masked) ? GUC_REGSET_MASKED : 0)
+
+static void guc_mmio_regset_init(struct temp_regset *regset,
+ struct intel_engine_cs *engine)
+{
+ const u32 base = engine->mmio_base;
+ struct i915_wa_list *wal = &engine->wa_list;
+ struct i915_wa *wa;
+ unsigned int i;
+
+ regset->used = 0;
+
+ GUC_MMIO_REG_ADD(regset, RING_MODE_GEN7(base), true);
+ GUC_MMIO_REG_ADD(regset, RING_HWS_PGA(base), false);
+ GUC_MMIO_REG_ADD(regset, RING_IMR(base), false);
+
+ for (i = 0, wa = wal->list; i < wal->count; i++, wa++)
+ GUC_MMIO_REG_ADD(regset, wa->reg, wa->masked_reg);
+
+ /* Be extra paranoid and include all whitelist registers. */
+ for (i = 0; i < RING_MAX_NONPRIV_SLOTS; i++)
+ GUC_MMIO_REG_ADD(regset,
+ RING_FORCE_TO_NONPRIV(base, i),
+ false);
+
+ /* add in local MOCS registers */
+ for (i = 0; i < GEN9_LNCFCMOCS_REG_COUNT; i++)
+ GUC_MMIO_REG_ADD(regset, GEN9_LNCFCMOCS(i), false);
+}
+
+static int guc_mmio_reg_state_query(struct intel_guc *guc)
+{
+ struct intel_gt *gt = guc_to_gt(guc);
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+ struct temp_regset temp_set;
+ u32 total;
+
+ /*
+ * Need to actually build the list in order to filter out
+ * duplicates and other such data dependent constructions.
+ */
+ temp_set.size = MAX_MMIO_REGS;
+ temp_set.registers = kmalloc_array(temp_set.size,
+ sizeof(*temp_set.registers),
+ GFP_KERNEL);
+ if (!temp_set.registers)
+ return -ENOMEM;
+
+ total = 0;
+ for_each_engine(engine, gt, id) {
+ guc_mmio_regset_init(&temp_set, engine);
+ total += temp_set.used;
+ }
+
+ kfree(temp_set.registers);
+
+ return total * sizeof(struct guc_mmio_reg);
+}
+
+static void guc_mmio_reg_state_init(struct intel_guc *guc,
+ struct __guc_ads_blob *blob)
+{
+ struct intel_gt *gt = guc_to_gt(guc);
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+ struct temp_regset temp_set;
+ struct guc_mmio_reg_set *ads_reg_set;
+ u32 addr_ggtt, offset;
+ u8 guc_class;
+
+ offset = guc_ads_regset_offset(guc);
+ addr_ggtt = intel_guc_ggtt_offset(guc, guc->ads_vma) + offset;
+ temp_set.registers = (struct guc_mmio_reg *) (((u8 *) blob) + offset);
+ temp_set.size = guc->ads_regset_size / sizeof(temp_set.registers[0]);
+
+ for_each_engine(engine, gt, id) {
+ /* Class index is checked in class converter */
+ GEM_BUG_ON(engine->instance >= GUC_MAX_INSTANCES_PER_CLASS);
+
+ guc_class = engine_class_to_guc_class(engine->class);
+ ads_reg_set = &blob->ads.reg_state_list[guc_class][engine->instance];
+
+ guc_mmio_regset_init(&temp_set, engine);
+ if (!temp_set.used) {
+ ads_reg_set->address = 0;
+ ads_reg_set->count = 0;
+ continue;
+ }
+
+ ads_reg_set->address = addr_ggtt;
+ ads_reg_set->count = temp_set.used;
+
+ temp_set.size -= temp_set.used;
+ temp_set.registers += temp_set.used;
+ addr_ggtt += temp_set.used * sizeof(struct guc_mmio_reg);
+ }
+
+ GEM_BUG_ON(temp_set.size);
+}
+
/*
* The first 80 dwords of the register state context, containing the
* execlists and ppgtt registers.
@@ -121,8 +304,7 @@ static void __guc_ads_init(struct intel_guc *guc)
*/
blob->ads.golden_context_lrca[guc_class] = 0;
blob->ads.eng_state_size[guc_class] =
- intel_engine_context_size(guc_to_gt(guc),
- engine_class) -
+ intel_engine_context_size(gt, engine_class) -
skipped_size;
}

@@ -153,6 +335,9 @@ static void __guc_ads_init(struct intel_guc *guc)
blob->ads.scheduler_policies = base + ptr_offset(blob, policies);
blob->ads.gt_system_info = base + ptr_offset(blob, system_info);

+ /* MMIO save/restore list */
+ guc_mmio_reg_state_init(guc, blob);
+
/* Private Data */
blob->ads.private_data = base + guc_ads_private_data_offset(guc);

@@ -173,6 +358,12 @@ int intel_guc_ads_create(struct intel_guc *guc)

GEM_BUG_ON(guc->ads_vma);

+ /* Need to calculate the reg state size dynamically: */
+ ret = guc_mmio_reg_state_query(guc);
+ if (ret < 0)
+ return ret;
+ guc->ads_regset_size = ret;
+
size = guc_ads_blob_size(guc);

ret = intel_guc_allocate_and_map_vma(guc, size, &guc->ads_vma,
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 52f878664e1e..4dce62e2382a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -12320,6 +12320,7 @@ enum skl_power_gate {

/* MOCS (Memory Object Control State) registers */
#define GEN9_LNCFCMOCS(i) _MMIO(0xb020 + (i) * 4) /* L3 Cache Control */
+#define GEN9_LNCFCMOCS_REG_COUNT 32

#define __GEN9_RCS0_MOCS0 0xc800
#define GEN9_GFX_MOCS(i) _MMIO(__GEN9_RCS0_MOCS0 + (i) * 4)