[PATCH] drm/i915: Split alloc from init for lrc

Nick Hoath
2015-08-19T12:26:06Z

Extend init/init_hw split to context init.
- Move context initialisation in to i915_gem_init_hw
- Move one off initialisation for render ring to
i915_gem_validate_context
- Move default context initialisation to logical_ring_init

Rename intel_lr_context_deferred_create to
intel_lr_context_deferred_alloc, to reflect reduced functionality &
alloc/init split.

This patch is intended to split out the allocation of resources & initialisation
to allow easier reuse of code for resume/gpu reset.

v2: Removed function ptr wrapping of do_switch_context (Daniel Vetter)
Left ->init_context int intel_lr_context_deferred_alloc (Daniel Vetter)
Remove unnecessary init flag & ring type test. (Daniel Vetter)
Improve commit message (Daniel Vetter)
v3: On init/reinit, set the hw next sequence number to the sw next sequence
number. This is set to 1 at driver load time. This prevents the seqno
being reset on reinit (Chris Wilson)

Issue: VIZ-4798
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/i915_drv.h | 1 -
drivers/gpu/drm/i915/i915_gem.c | 18 ++--
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 3 +-
drivers/gpu/drm/i915/intel_lrc.c | 147 ++++++++++++++---------------
drivers/gpu/drm/i915/intel_lrc.h | 4 +-
5 files changed, 86 insertions(+), 87 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index f7fd519..844ccf0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -880,7 +880,6 @@ struct intel_context {
} legacy_hw_ctx;

/* Execlists */
- bool rcs_initialized;
struct {
struct drm_i915_gem_object *state;
struct intel_ringbuffer *ringbuf;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 73293b4..eb7c1f2 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4603,14 +4603,8 @@ int i915_gem_init_rings(struct drm_device *dev)
goto cleanup_vebox_ring;
}

- ret = i915_gem_set_seqno(dev, ((u32)~0 - 0x1000));
- if (ret)
- goto cleanup_bsd2_ring;
-
return 0;

-cleanup_bsd2_ring:
- intel_cleanup_ring_buffer(&dev_priv->ring[VCS2]);
cleanup_vebox_ring:
intel_cleanup_ring_buffer(&dev_priv->ring[VECS]);
cleanup_blt_ring:
@@ -4629,6 +4623,7 @@ i915_gem_init_hw(struct drm_device *dev)
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_engine_cs *ring;
int ret, i, j;
+ struct drm_i915_gem_request *req;

if (INTEL_INFO(dev)->gen < 6 && !intel_enable_gtt())
return -EIO;
@@ -4680,9 +4675,12 @@ i915_gem_init_hw(struct drm_device *dev)
goto out;
}

+ ret = i915_gem_set_seqno(dev, dev_priv->next_seqno);
+ if (ret)
+ goto out;
+
/* Now it is safe to go back round and do everything else: */
for_each_ring(ring, dev_priv, i) {
- struct drm_i915_gem_request *req;

WARN_ON(!ring->default_context);

@@ -4881,6 +4879,12 @@ i915_gem_load(struct drm_device *dev)
dev_priv->num_fence_regs =
I915_READ(vgtif_reg(avail_rs.fence_num));

+ /*
+ * Set initial sequence number for requests.
+ */
+ dev_priv->next_seqno = 1;
+ dev_priv->last_seqno = ~((uint32_t)0);
+
/* Initialize fence registers to zero */
INIT_LIST_HEAD(&dev_priv->mm.fence_list);
i915_gem_restore_fences(dev);
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 923a3c4..95f1a0d 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -994,6 +994,7 @@ i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
{
struct intel_context *ctx = NULL;
struct i915_ctx_hang_stats *hs;
+ int ret;

if (ring->id != RCS && ctx_id != DEFAULT_CONTEXT_HANDLE)
return ERR_PTR(-EINVAL);
@@ -1009,7 +1010,7 @@ i915_gem_validate_context(struct drm_device *dev, struct drm_file *file,
}

if (i915.enable_execlists && !ctx->engine[ring->id].state) {
- int ret = intel_lr_context_deferred_create(ctx, ring);
+ ret = intel_lr_context_deferred_alloc(ctx, ring);
if (ret) {
DRM_DEBUG("Could not create LRC %u: %d\n", ctx_id, ret);
return ERR_PTR(ret);
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 138964a..d0dc6b5 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1426,11 +1426,31 @@ out:
return ret;
}

+static void lrc_setup_hardware_status_page(struct intel_engine_cs *ring,
+ struct drm_i915_gem_object *default_ctx_obj)
+{
+ struct drm_i915_private *dev_priv = ring->dev->dev_private;
+
+ /* The status page is offset 0 from the default context object
+ * in LRC mode. */
+ ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(default_ctx_obj);
+ ring->status_page.page_addr =
+ kmap(sg_page(default_ctx_obj->pages->sgl));
+ ring->status_page.obj = default_ctx_obj;
+
+ I915_WRITE(RING_HWS_PGA(ring->mmio_base),
+ (u32)ring->status_page.gfx_addr);
+ POSTING_READ(RING_HWS_PGA(ring->mmio_base));
+}
+
static int gen8_init_common_ring(struct intel_engine_cs *ring)
{
struct drm_device *dev = ring->dev;
struct drm_i915_private *dev_priv = dev->dev_private;

+ lrc_setup_hardware_status_page(ring,
+ ring->default_context->engine[ring->id].state);
+
I915_WRITE_IMR(ring, ~(ring->irq_enable_mask | ring->irq_keep_mask));
I915_WRITE(RING_HWSTAM(ring->mmio_base), 0xffffffff);

@@ -1841,8 +1861,33 @@ static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *rin
if (ret)
return ret;

- ret = intel_lr_context_deferred_create(ring->default_context, ring);
+ ret = intel_lr_context_deferred_alloc(ring->default_context, ring);
+ if (ret)
+ return ret;

+ ret = i915_gem_obj_ggtt_pin(
+ ring->default_context->engine[ring->id].state,
+ GEN8_LR_CONTEXT_ALIGN, 0);
+ if (ret) {
+ DRM_DEBUG_DRIVER("Pin LRC backing obj failed: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = intel_pin_and_map_ringbuffer_obj(dev,
+ ring->default_context->engine[ring->id].ringbuf);
+ if (ret) {
+ DRM_ERROR(
+ "Failed to pin and map ringbuffer %s: %d\n",
+ ring->name, ret);
+ goto error_unpin_ggtt;
+ }
+
+ return ret;
+
+error_unpin_ggtt:
+ i915_gem_object_ggtt_unpin(
+ ring->default_context->engine[ring->id].state);
return ret;
}

@@ -2044,14 +2089,8 @@ int intel_logical_rings_init(struct drm_device *dev)
goto cleanup_vebox_ring;
}

- ret = i915_gem_set_seqno(dev, ((u32)~0 - 0x1000));
- if (ret)
- goto cleanup_bsd2_ring;
-
return 0;

-cleanup_bsd2_ring:
- intel_logical_ring_cleanup(&dev_priv->ring[VCS2]);
cleanup_vebox_ring:
intel_logical_ring_cleanup(&dev_priv->ring[VECS]);
cleanup_blt_ring:
@@ -2303,25 +2342,8 @@ static uint32_t get_lr_context_size(struct intel_engine_cs *ring)
return ret;
}

-static void lrc_setup_hardware_status_page(struct intel_engine_cs *ring,
- struct drm_i915_gem_object *default_ctx_obj)
-{
- struct drm_i915_private *dev_priv = ring->dev->dev_private;
-
- /* The status page is offset 0 from the default context object
- * in LRC mode. */
- ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(default_ctx_obj);
- ring->status_page.page_addr =
- kmap(sg_page(default_ctx_obj->pages->sgl));
- ring->status_page.obj = default_ctx_obj;
-
- I915_WRITE(RING_HWS_PGA(ring->mmio_base),
- (u32)ring->status_page.gfx_addr);
- POSTING_READ(RING_HWS_PGA(ring->mmio_base));
-}
-
/**
- * intel_lr_context_deferred_create() - create the LRC specific bits of a context
+ * intel_lr_context_deferred_alloc() - create the LRC specific bits of a context
* @ctx: LR context to create.
* @ring: engine to be used with the context.
*
@@ -2333,10 +2355,10 @@ static void lrc_setup_hardware_status_page(struct intel_engine_cs *ring,
*
* Return: non-zero on error.
*/
-int intel_lr_context_deferred_create(struct intel_context *ctx,
+
+int intel_lr_context_deferred_alloc(struct intel_context *ctx,
struct intel_engine_cs *ring)
{
- const bool is_global_default_ctx = (ctx == ring->default_context);
struct drm_device *dev = ring->dev;
struct drm_i915_gem_object *ctx_obj;
uint32_t context_size;
@@ -2354,22 +2376,12 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
return -ENOMEM;
}

- if (is_global_default_ctx) {
- ret = i915_gem_obj_ggtt_pin(ctx_obj, GEN8_LR_CONTEXT_ALIGN, 0);
- if (ret) {
- DRM_DEBUG_DRIVER("Pin LRC backing obj failed: %d\n",
- ret);
- drm_gem_object_unreference(&ctx_obj->base);
- return ret;
- }
- }
-
ringbuf = kzalloc(sizeof(*ringbuf), GFP_KERNEL);
if (!ringbuf) {
DRM_DEBUG_DRIVER("Failed to allocate ringbuffer %s\n",
ring->name);
ret = -ENOMEM;
- goto error_unpin_ctx;
+ goto error_deref_obj;
}

ringbuf->ring = ring;
@@ -2389,66 +2401,49 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
ring->name, ret);
goto error_free_rbuf;
}
-
- if (is_global_default_ctx) {
- ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
- if (ret) {
- DRM_ERROR(
- "Failed to pin and map ringbuffer %s: %d\n",
- ring->name, ret);
- goto error_destroy_rbuf;
- }
- }
-
}

ret = populate_lr_context(ctx, ctx_obj, ring, ringbuf);
if (ret) {
DRM_DEBUG_DRIVER("Failed to populate LRC: %d\n", ret);
- goto error;
+ goto error_destroy_rbuf;
}

ctx->engine[ring->id].ringbuf = ringbuf;
ctx->engine[ring->id].state = ctx_obj;

- if (ctx == ring->default_context)
- lrc_setup_hardware_status_page(ring, ctx_obj);
- else if (ring->id == RCS && !ctx->rcs_initialized) {
- if (ring->init_context) {
- struct drm_i915_gem_request *req;
+ if (ctx != ring->default_context && ring->init_context) {
+ struct drm_i915_gem_request *req;

- ret = i915_gem_request_alloc(ring, ctx, &req);
- if (ret)
- return ret;
-
- ret = ring->init_context(req);
- if (ret) {
- DRM_ERROR("ring init context: %d\n", ret);
- i915_gem_request_cancel(req);
- ctx->engine[ring->id].ringbuf = NULL;
- ctx->engine[ring->id].state = NULL;
- goto error;
- }
-
- i915_add_request_no_flush(req);
+ ret = i915_gem_request_alloc(ring,
+ ring->default_context, &req);
+ if (ret) {
+ DRM_ERROR("ring create req: %d\n",
+ ret);
+ i915_gem_request_cancel(req);
+ goto error_destroy_rbuf;
}

- ctx->rcs_initialized = true;
+ ret = ring->init_context(req);
+ if (ret) {
+ DRM_ERROR("ring init context: %d\n",
+ ret);
+ i915_gem_request_cancel(req);
+ goto error_destroy_rbuf;
+ }
+ i915_add_request_no_flush(req);
}

return 0;

-error:
- if (is_global_default_ctx)
- intel_unpin_ringbuffer_obj(ringbuf);
error_destroy_rbuf:
intel_destroy_ringbuffer_obj(ringbuf);
error_free_rbuf:
kfree(ringbuf);
-error_unpin_ctx:
- if (is_global_default_ctx)
- i915_gem_object_ggtt_unpin(ctx_obj);
+error_deref_obj:
drm_gem_object_unreference(&ctx_obj->base);
+ ctx->engine[ring->id].ringbuf = NULL;
+ ctx->engine[ring->id].state = NULL;
return ret;
}

diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h
index 64f89f99..109147e 100644
--- a/drivers/gpu/drm/i915/intel_lrc.h
+++ b/drivers/gpu/drm/i915/intel_lrc.h
@@ -69,8 +69,8 @@ static inline void intel_logical_ring_emit(struct intel_ringbuffer *ringbuf,

/* Logical Ring Contexts */
void intel_lr_context_free(struct intel_context *ctx);
-int intel_lr_context_deferred_create(struct intel_context *ctx,
- struct intel_engine_cs *ring);
+int intel_lr_context_deferred_alloc(struct intel_context *ctx,
+ struct intel_engine_cs *ring);
void intel_lr_context_unpin(struct drm_i915_gem_request *req);
void intel_lr_context_reset(struct drm_device *dev,
struct intel_context *ctx);
--
2.1.1