[Intel-gfx] [PATCH 2/5] drm/i915/gt: Use cmd_cctl override for platforms >= gen12
Ayaz A Siddiqui
ayaz.siddiqui at intel.com
Thu Aug 12 06:47:55 UTC 2021
From: Srinivasan Shanmugam <srinivasan.s at intel.com>
Program CMD_CCTL to use a mocs entry for uncached access.
This controls memory accesses by CS as it reads instructions
from the ring and batch buffers.
Signed-off-by: Srinivasan Shanmugam <srinivasan.s at intel.com>
Signed-off-by: Ayaz A Siddiqui <ayaz.siddiqui at intel.com>
Cc: Chris Wilson <chris.p.wilson at intel.com>
Cc: Matt Roper <matthew.d.roper at intel.com>
---
drivers/gpu/drm/i915/gt/intel_mocs.c | 96 +++++++++++++++++++++++++
drivers/gpu/drm/i915/gt/selftest_mocs.c | 49 +++++++++++++
drivers/gpu/drm/i915/i915_reg.h | 16 +++++
3 files changed, 161 insertions(+)
diff --git a/drivers/gpu/drm/i915/gt/intel_mocs.c b/drivers/gpu/drm/i915/gt/intel_mocs.c
index c66e226e71499..dc3357bc228e1 100644
--- a/drivers/gpu/drm/i915/gt/intel_mocs.c
+++ b/drivers/gpu/drm/i915/gt/intel_mocs.c
@@ -25,6 +25,15 @@ struct drm_i915_mocs_table {
u8 uc_index;
};
+struct drm_i915_aux_table {
+ const char *name;
+ i915_reg_t offset;
+ u32 value;
+ u32 readmask;
+ bool skip_check;
+ struct drm_i915_aux_table *next;
+};
+
/* Defines for the tables (XXX_MOCS_0 - XXX_MOCS_63) */
#define _LE_CACHEABILITY(value) ((value) << 0)
#define _LE_TGT_CACHE(value) ((value) << 2)
@@ -336,6 +345,86 @@ static bool has_mocs(const struct drm_i915_private *i915)
return !IS_DGFX(i915);
}
+static struct drm_i915_aux_table *
+add_aux_reg(struct drm_i915_aux_table *aux,
+ const char *name,
+ i915_reg_t offset,
+ u32 value,
+ u32 read,
+ bool skip_check)
+
+{
+ struct drm_i915_aux_table *x;
+
+ x = kmalloc(sizeof(*x), GFP_ATOMIC);
+ if (!x) {
+ DRM_ERROR("Failed to allocate aux reg '%s'\n", name);
+ return aux;
+ }
+
+ x->name = name;
+ x->offset = offset;
+ x->value = value;
+ x->readmask = read;
+ x->skip_check = skip_check;
+
+ x->next = aux;
+ return x;
+}
+
+static struct drm_i915_aux_table *
+add_cmd_cctl_override(struct drm_i915_aux_table *aux, u8 idx)
+{
+ return add_aux_reg(aux,
+ "CMD_CCTL",
+ RING_CMD_CCTL(0),
+ CMD_CCTL_MOCS_OVERRIDE(idx, idx),
+ CMD_CCTL_WRITE_OVERRIDE_MASK | CMD_CCTL_READ_OVERRIDE_MASK,
+ false);
+}
+
+static const struct drm_i915_aux_table *
+build_aux_regs(const struct intel_engine_cs *engine,
+ const struct drm_i915_mocs_table *mocs)
+{
+ struct drm_i915_aux_table *aux = NULL;
+
+ if (GRAPHICS_VER(engine->i915) >= 12 &&
+ !drm_WARN_ONCE(&engine->i915->drm, !mocs->uc_index,
+ "Platform that should have UC index defined and does not\n")) {
+ /*
+ * Index-0 does not operate as an uncached value as believed,
+ * but causes invalid write cycles. Steer CMD_CCTL to another
+ * uncached index.
+ */
+ aux = add_cmd_cctl_override(aux, mocs->uc_index);
+ }
+
+ return aux;
+}
+
+static void
+free_aux_regs(const struct drm_i915_aux_table *aux)
+{
+ while (aux) {
+ struct drm_i915_aux_table *next = aux->next;
+
+ kfree(aux);
+ aux = next;
+ }
+}
+
+static void apply_aux_regs(struct intel_engine_cs *engine,
+ const struct drm_i915_aux_table *aux)
+{
+ while (aux) {
+ intel_uncore_write_fw(engine->uncore,
+ _MMIO(engine->mmio_base + i915_mmio_reg_offset(aux->offset)),
+ aux->value);
+ aux = aux->next;
+ }
+}
+
static unsigned int get_mocs_settings(const struct drm_i915_private *i915,
struct drm_i915_mocs_table *table)
{
@@ -347,10 +436,12 @@ static unsigned int get_mocs_settings(const struct drm_i915_private *i915,
table->size = ARRAY_SIZE(dg1_mocs_table);
table->table = dg1_mocs_table;
table->n_entries = GEN9_NUM_MOCS_ENTRIES;
+ table->uc_index = 1;
} else if (GRAPHICS_VER(i915) >= 12) {
table->size = ARRAY_SIZE(tgl_mocs_table);
table->table = tgl_mocs_table;
table->n_entries = GEN9_NUM_MOCS_ENTRIES;
+ table->uc_index = 3;
} else if (GRAPHICS_VER(i915) == 11) {
table->size = ARRAY_SIZE(icl_mocs_table);
table->table = icl_mocs_table;
@@ -484,6 +575,7 @@ static void init_l3cc_table(struct intel_engine_cs *engine,
void intel_mocs_init_engine(struct intel_engine_cs *engine)
{
+ const struct drm_i915_aux_table *aux;
struct drm_i915_mocs_table table;
unsigned int flags;
@@ -500,6 +592,10 @@ void intel_mocs_init_engine(struct intel_engine_cs *engine)
if (flags & HAS_RENDER_L3CC && engine->class == RENDER_CLASS)
init_l3cc_table(engine, &table);
+
+ aux = build_aux_regs(engine, &table);
+ apply_aux_regs(engine, aux);
+ free_aux_regs(aux);
}
static u32 global_mocs_offset(void)
diff --git a/drivers/gpu/drm/i915/gt/selftest_mocs.c b/drivers/gpu/drm/i915/gt/selftest_mocs.c
index 13d25bf2a94aa..ecadc9686ac01 100644
--- a/drivers/gpu/drm/i915/gt/selftest_mocs.c
+++ b/drivers/gpu/drm/i915/gt/selftest_mocs.c
@@ -155,6 +155,47 @@ static int read_l3cc_table(struct i915_request *rq,
return read_regs(rq, addr, (table->n_entries + 1) / 2, offset);
}
+static int read_aux_regs(struct i915_request *rq,
+ const struct drm_i915_aux_table *r,
+ u32 *offset)
+{
+ int err;
+
+ while (r) {
+ err = read_regs(rq,
+ rq->engine->mmio_base + i915_mmio_reg_offset(r->offset), 1,
+ offset);
+ if (err)
+ return err;
+
+ r = r->next;
+ }
+
+ return 0;
+}
+
+static int check_aux_regs(struct intel_engine_cs *engine,
+ const struct drm_i915_aux_table *r,
+ u32 **vaddr)
+{
+ while (r) {
+ u32 expect = r->value & r->readmask;
+ u32 masked_value = **vaddr & r->readmask;
+
+ if (!r->skip_check && (masked_value != expect)) {
+ pr_err("%s: Invalid entry %s[%x]=0x%x, relevant bits were 0x%x vs expected 0x%x\n",
+ engine->name, r->name,
+ i915_mmio_reg_offset(r->offset), **vaddr,
+ masked_value, expect);
+ return -EINVAL;
+ }
+ ++*vaddr;
+ r = r->next;
+ }
+
+ return 0;
+}
+
static int check_mocs_table(struct intel_engine_cs *engine,
const struct drm_i915_mocs_table *table,
u32 **vaddr)
@@ -216,6 +257,7 @@ static int check_mocs_engine(struct live_mocs *arg,
struct intel_context *ce)
{
struct i915_vma *vma = arg->scratch;
+ const struct drm_i915_aux_table *aux;
struct i915_request *rq;
u32 offset;
u32 *vaddr;
@@ -223,6 +265,8 @@ static int check_mocs_engine(struct live_mocs *arg,
memset32(arg->vaddr, STACK_MAGIC, PAGE_SIZE / sizeof(u32));
+ aux = build_aux_regs(ce->engine, &arg->table);
+
rq = intel_context_create_request(ce);
if (IS_ERR(rq))
return PTR_ERR(rq);
@@ -239,6 +283,8 @@ static int check_mocs_engine(struct live_mocs *arg,
err = read_mocs_table(rq, arg->mocs, &offset);
if (!err && ce->engine->class == RENDER_CLASS)
err = read_l3cc_table(rq, arg->l3cc, &offset);
+ if (!err)
+ err = read_aux_regs(rq, aux, &offset);
offset -= i915_ggtt_offset(vma);
GEM_BUG_ON(offset > PAGE_SIZE);
@@ -252,10 +298,13 @@ static int check_mocs_engine(struct live_mocs *arg,
err = check_mocs_table(ce->engine, arg->mocs, &vaddr);
if (!err && ce->engine->class == RENDER_CLASS)
err = check_l3cc_table(ce->engine, arg->l3cc, &vaddr);
+ if (!err)
+ err = check_aux_regs(ce->engine, aux, &vaddr);
if (err)
return err;
GEM_BUG_ON(arg->vaddr + offset != vaddr);
+ free_aux_regs(aux);
return 0;
}
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 664970f2bc62a..c8e2ca1b20796 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2551,6 +2551,22 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define RING_HWS_PGA(base) _MMIO((base) + 0x80)
#define RING_ID(base) _MMIO((base) + 0x8c)
#define RING_HWS_PGA_GEN6(base) _MMIO((base) + 0x2080)
+
+#define RING_CMD_CCTL(base) _MMIO((base) + 0xc4)
+/*
+ * CMD_CCTL read/write fields take a MOCS value and _not_ a table index.
+ * The lsb of each can be considered a separate enabling bit for encryption.
+ * 6:0 == default MOCS value for reads => 6:1 == table index for reads.
+ * 13:7 == default MOCS value for writes => 13:8 == table index for writes.
+ * 15:14 == Reserved => 31:30 are set to 0.
+ */
+#define CMD_CCTL_WRITE_OVERRIDE_MASK REG_GENMASK(13, 7)
+#define CMD_CCTL_READ_OVERRIDE_MASK REG_GENMASK(6, 0)
+#define CMD_CCTL_MOCS_OVERRIDE(write, read) \
+ _MASKED_FIELD(CMD_CCTL_WRITE_OVERRIDE_MASK | CMD_CCTL_READ_OVERRIDE_MASK, \
+ REG_FIELD_PREP(CMD_CCTL_WRITE_OVERRIDE_MASK, (write) << 1) | \
+ REG_FIELD_PREP(CMD_CCTL_READ_OVERRIDE_MASK, (read) << 1))
+
#define RING_RESET_CTL(base) _MMIO((base) + 0xd0)
#define RESET_CTL_CAT_ERROR REG_BIT(2)
#define RESET_CTL_READY_TO_RESET REG_BIT(1)
--
2.26.2
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