[PATCH 5.10 013/152] drm/i915/gt: Limit VFE threads based on GT

From: Chris Wilson chris@chris-wilson.co.uk

commit ffaf97899c4a58b9fefb11534f730785443611a8 upstream.

MEDIA_STATE_VFE only accepts the 'maximum number of threads' in the range [0, n-1] where n is #EU * (#threads/EU) with the number of threads based on plaform and the number of EU based on the number of slices and subslices. This is a fixed number per platform/gt, so appropriately limit the number of threads we spawn to match the device.

v2: Oversaturate the system with tasks to force execution on every HW thread; if the thread idles it is returned to the pool and may be reused again before an unused thread.

v3: Fix more state commands, which was causing Baytrail to barf. v4: STATE_CACHE_INVALIDATE requires a stall on Ivybridge

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2024 Fixes: 47f8253d2b89 ("drm/i915/gen7: Clear all EU/L3 residual contexts") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Mika Kuoppala mika.kuoppala@linux.intel.com Cc: Prathap Kumar Valsan prathap.kumar.valsan@intel.com Cc: Akeem G Abodunrin akeem.g.abodunrin@intel.com Cc: Jon Bloomfield jon.bloomfield@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Randy Wright rwright@hpe.com Cc: stable@vger.kernel.org # v5.7+ Reviewed-by: Akeem G Abodunrin akeem.g.abodunrin@intel.com Reviewed-by: Rodrigo Vivi rodrigo.vivi@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20210111225220.3483-1-chris@ch... (cherry picked from commit eebfb32e26851662d24ea86dd381fd0f83cd4b47) Signed-off-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/gpu/drm/i915/gt/gen7_renderclear.c | 157 +++++++++++++++++------------ 1 file changed, 94 insertions(+), 63 deletions(-)

--- a/drivers/gpu/drm/i915/gt/gen7_renderclear.c +++ b/drivers/gpu/drm/i915/gt/gen7_renderclear.c @@ -7,8 +7,6 @@ #include "i915_drv.h" #include "intel_gpu_commands.h"

-#define MAX_URB_ENTRIES 64 -#define STATE_SIZE (4 * 1024) #define GT3_INLINE_DATA_DELAYS 0x1E00 #define batch_advance(Y, CS) GEM_BUG_ON((Y)->end != (CS))

@@ -34,38 +32,59 @@ struct batch_chunk { };

struct batch_vals { - u32 max_primitives; - u32 max_urb_entries; - u32 cmd_size; - u32 state_size; + u32 max_threads; u32 state_start; - u32 batch_size; + u32 surface_start; u32 surface_height; u32 surface_width; - u32 scratch_size; - u32 max_size; + u32 size; };

+static inline int num_primitives(const struct batch_vals *bv) +{ + /* + * We need to saturate the GPU with work in order to dispatch + * a shader on every HW thread, and clear the thread-local registers. + * In short, we have to dispatch work faster than the shaders can + * run in order to fill the EU and occupy each HW thread. + */ + return bv->max_threads; +} + static void batch_get_defaults(struct drm_i915_private *i915, struct batch_vals *bv) { if (IS_HASWELL(i915)) { - bv->max_primitives = 280; - bv->max_urb_entries = MAX_URB_ENTRIES; + switch (INTEL_INFO(i915)->gt) { + default: + case 1: + bv->max_threads = 70; + break; + case 2: + bv->max_threads = 140; + break; + case 3: + bv->max_threads = 280; + break; + } bv->surface_height = 16 * 16; bv->surface_width = 32 * 2 * 16; } else { - bv->max_primitives = 128; - bv->max_urb_entries = MAX_URB_ENTRIES / 2; + switch (INTEL_INFO(i915)->gt) { + default: + case 1: /* including vlv */ + bv->max_threads = 36; + break; + case 2: + bv->max_threads = 128; + break; + } bv->surface_height = 16 * 8; bv->surface_width = 32 * 16; } - bv->cmd_size = bv->max_primitives * 4096; - bv->state_size = STATE_SIZE; - bv->state_start = bv->cmd_size; - bv->batch_size = bv->cmd_size + bv->state_size; - bv->scratch_size = bv->surface_height * bv->surface_width; - bv->max_size = bv->batch_size + bv->scratch_size; + bv->state_start = round_up(SZ_1K + num_primitives(bv) * 64, SZ_4K); + bv->surface_start = bv->state_start + SZ_4K; + bv->size = bv->surface_start + bv->surface_height * bv->surface_width; }

static void batch_init(struct batch_chunk *bc, @@ -155,7 +174,8 @@ static u32 gen7_fill_binding_table(struct batch_chunk *state, const struct batch_vals *bv) { - u32 surface_start = gen7_fill_surface_state(state, bv->batch_size, bv); + u32 surface_start = + gen7_fill_surface_state(state, bv->surface_start, bv); u32 *cs = batch_alloc_items(state, 32, 8); u32 offset = batch_offset(state, cs);

@@ -214,9 +234,9 @@ static void gen7_emit_state_base_address(struct batch_chunk *batch, u32 surface_state_base) { - u32 *cs = batch_alloc_items(batch, 0, 12); + u32 *cs = batch_alloc_items(batch, 0, 10);

- *cs++ = STATE_BASE_ADDRESS | (12 - 2); + *cs++ = STATE_BASE_ADDRESS | (10 - 2); /* general */ *cs++ = batch_addr(batch) | BASE_ADDRESS_MODIFY; /* surface */ @@ -233,8 +253,6 @@ gen7_emit_state_base_address(struct batc *cs++ = BASE_ADDRESS_MODIFY; *cs++ = 0; *cs++ = BASE_ADDRESS_MODIFY; - *cs++ = 0; - *cs++ = 0; batch_advance(batch, cs); }

@@ -244,8 +262,7 @@ gen7_emit_vfe_state(struct batch_chunk * u32 urb_size, u32 curbe_size, u32 mode) { - u32 urb_entries = bv->max_urb_entries; - u32 threads = bv->max_primitives - 1; + u32 threads = bv->max_threads - 1; u32 *cs = batch_alloc_items(batch, 32, 8);

*cs++ = MEDIA_VFE_STATE | (8 - 2); @@ -254,7 +271,7 @@ gen7_emit_vfe_state(struct batch_chunk * *cs++ = 0;

/* number of threads & urb entries for GPGPU vs Media Mode */ - *cs++ = threads << 16 | urb_entries << 8 | mode << 2; + *cs++ = threads << 16 | 1 << 8 | mode << 2;

*cs++ = 0;

@@ -293,17 +310,12 @@ gen7_emit_media_object(struct batch_chun { unsigned int x_offset = (media_object_index % 16) * 64; unsigned int y_offset = (media_object_index / 16) * 16; - unsigned int inline_data_size; - unsigned int media_batch_size; - unsigned int i; + unsigned int pkt = 6 + 3; u32 *cs;

- inline_data_size = 112 * 8; - media_batch_size = inline_data_size + 6; - - cs = batch_alloc_items(batch, 8, media_batch_size); + cs = batch_alloc_items(batch, 8, pkt);

- *cs++ = MEDIA_OBJECT | (media_batch_size - 2); + *cs++ = MEDIA_OBJECT | (pkt - 2);

/* interface descriptor offset */ *cs++ = 0; @@ -317,25 +329,44 @@ gen7_emit_media_object(struct batch_chun *cs++ = 0;

/* inline */ - *cs++ = (y_offset << 16) | (x_offset); + *cs++ = y_offset << 16 | x_offset; *cs++ = 0; *cs++ = GT3_INLINE_DATA_DELAYS; - for (i = 3; i < inline_data_size; i++) - *cs++ = 0;

batch_advance(batch, cs); }

static void gen7_emit_pipeline_flush(struct batch_chunk *batch) { - u32 *cs = batch_alloc_items(batch, 0, 5); + u32 *cs = batch_alloc_items(batch, 0, 4);

- *cs++ = GFX_OP_PIPE_CONTROL(5); - *cs++ = PIPE_CONTROL_STATE_CACHE_INVALIDATE | - PIPE_CONTROL_GLOBAL_GTT_IVB; + *cs++ = GFX_OP_PIPE_CONTROL(4); + *cs++ = PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH | + PIPE_CONTROL_DEPTH_CACHE_FLUSH | + PIPE_CONTROL_DC_FLUSH_ENABLE | + PIPE_CONTROL_CS_STALL; *cs++ = 0; *cs++ = 0; + + batch_advance(batch, cs); +} + +static void gen7_emit_pipeline_invalidate(struct batch_chunk *batch) +{ + u32 *cs = batch_alloc_items(batch, 0, 8); + + /* ivb: Stall before STATE_CACHE_INVALIDATE */ + *cs++ = GFX_OP_PIPE_CONTROL(4); + *cs++ = PIPE_CONTROL_STALL_AT_SCOREBOARD | + PIPE_CONTROL_CS_STALL; + *cs++ = 0; + *cs++ = 0; + + *cs++ = GFX_OP_PIPE_CONTROL(4); + *cs++ = PIPE_CONTROL_STATE_CACHE_INVALIDATE; *cs++ = 0; + *cs++ = 0; + batch_advance(batch, cs); }

@@ -344,34 +375,34 @@ static void emit_batch(struct i915_vma * const struct batch_vals *bv) { struct drm_i915_private *i915 = vma->vm->i915; - unsigned int desc_count = 64; - const u32 urb_size = 112; + const unsigned int desc_count = 1; + const unsigned int urb_size = 1; struct batch_chunk cmds, state; - u32 interface_descriptor; + u32 descriptors; unsigned int i;

- batch_init(&cmds, vma, start, 0, bv->cmd_size); - batch_init(&state, vma, start, bv->state_start, bv->state_size); + batch_init(&cmds, vma, start, 0, bv->state_start); + batch_init(&state, vma, start, bv->state_start, SZ_4K);

- interface_descriptor = - gen7_fill_interface_descriptor(&state, bv, - IS_HASWELL(i915) ? - &cb_kernel_hsw : - &cb_kernel_ivb, - desc_count); - gen7_emit_pipeline_flush(&cmds); + descriptors = gen7_fill_interface_descriptor(&state, bv, + IS_HASWELL(i915) ? + &cb_kernel_hsw : + &cb_kernel_ivb, + desc_count); + + gen7_emit_pipeline_invalidate(&cmds); batch_add(&cmds, PIPELINE_SELECT | PIPELINE_SELECT_MEDIA); batch_add(&cmds, MI_NOOP); - gen7_emit_state_base_address(&cmds, interface_descriptor); + gen7_emit_pipeline_invalidate(&cmds); + gen7_emit_pipeline_flush(&cmds); + gen7_emit_state_base_address(&cmds, descriptors); + gen7_emit_pipeline_invalidate(&cmds);

gen7_emit_vfe_state(&cmds, bv, urb_size - 1, 0, 0); + gen7_emit_interface_descriptor_load(&cmds, descriptors, desc_count);

- gen7_emit_interface_descriptor_load(&cmds, - interface_descriptor, - desc_count); - - for (i = 0; i < bv->max_primitives; i++) + for (i = 0; i < num_primitives(bv); i++) gen7_emit_media_object(&cmds, i);

batch_add(&cmds, MI_BATCH_BUFFER_END); @@ -385,15 +416,15 @@ int gen7_setup_clear_gpr_bb(struct intel

batch_get_defaults(engine->i915, &bv); if (!vma) - return bv.max_size; + return bv.size;

- GEM_BUG_ON(vma->obj->base.size < bv.max_size); + GEM_BUG_ON(vma->obj->base.size < bv.size);

batch = i915_gem_object_pin_map(vma->obj, I915_MAP_WC); if (IS_ERR(batch)) return PTR_ERR(batch);

- emit_batch(vma, memset(batch, 0, bv.max_size), &bv); + emit_batch(vma, memset(batch, 0, bv.size), &bv);

i915_gem_object_flush_map(vma->obj); __i915_gem_object_release_map(vma->obj);