Re: [Intel-gfx] [PATCH] drm/i915/gtt: reduce overzealous alignment constraints for GGTT

[Das, Nirmoy]

|Acked-by: Nirmoy Das |

On 03/03/2022 11:02, Matthew Auld wrote:

Currently this will enforce both 2M alignment and padding for any LMEM
pages inserted into the GGTT. However, this was only meant to be applied
to the compact-pt layout with the ppGTT. For the GGTT we can reduce the
alignment and padding to 64K.

Bspec: 45015
Fixes: 87bd701ee268 ("drm/i915: enforce min GTT alignment for discrete cards")
Signed-off-by: Matthew Auld
Cc: Thomas Hellström
Cc: Robert Beckett
Cc: Ramalingam C
---
  drivers/gpu/drm/i915/gt/intel_gtt.c | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c 
b/drivers/gpu/drm/i915/gt/intel_gtt.c
index 4bcdfcab3642..a5f5b2dda332 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.c
@@ -234,7 +234,8 @@ void i915_address_space_init(struct i915_address_space *vm, 
int subclass)
memset64(vm->min_alignment, I915_GTT_MIN_ALIGNMENT,
 ARRAY_SIZE(vm->min_alignment));
  
-	if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915)) {

+   if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915) &&
+   subclass == VM_CLASS_PPGTT) {
vm->min_alignment[INTEL_MEMORY_LOCAL] = I915_GTT_PAGE_SIZE_2M;
vm->min_alignment[INTEL_MEMORY_STOLEN_LOCAL] = 
I915_GTT_PAGE_SIZE_2M;
} else if (HAS_64K_PAGES(vm->i915)) {

Re: [Intel-gfx] [PATCH] drm/i915/gtt: reduce overzealous alignment constraints for GGTT

[Intel]

On 3/3/22 11:02, Matthew Auld wrote:

Currently this will enforce both 2M alignment and padding for any LMEM
pages inserted into the GGTT. However, this was only meant to be applied
to the compact-pt layout with the ppGTT. For the GGTT we can reduce the
alignment and padding to 64K.

Bspec: 45015
Fixes: 87bd701ee268 ("drm/i915: enforce min GTT alignment for discrete cards")
Signed-off-by: Matthew Auld 
Cc: Thomas Hellström 
Cc: Robert Beckett 
Cc: Ramalingam C 


Reviewed-by: Thomas Hellström 



---
  drivers/gpu/drm/i915/gt/intel_gtt.c | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c 
b/drivers/gpu/drm/i915/gt/intel_gtt.c
index 4bcdfcab3642..a5f5b2dda332 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.c
@@ -234,7 +234,8 @@ void i915_address_space_init(struct i915_address_space *vm, 
int subclass)
memset64(vm->min_alignment, I915_GTT_MIN_ALIGNMENT,
 ARRAY_SIZE(vm->min_alignment));
  
-	if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915)) {

+   if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915) &&
+   subclass == VM_CLASS_PPGTT) {
vm->min_alignment[INTEL_MEMORY_LOCAL] = I915_GTT_PAGE_SIZE_2M;
vm->min_alignment[INTEL_MEMORY_STOLEN_LOCAL] = 
I915_GTT_PAGE_SIZE_2M;
} else if (HAS_64K_PAGES(vm->i915)) {

[PATCH] drm/i915/gtt: reduce overzealous alignment constraints for GGTT

[Matthew Auld]

Currently this will enforce both 2M alignment and padding for any LMEM
pages inserted into the GGTT. However, this was only meant to be applied
to the compact-pt layout with the ppGTT. For the GGTT we can reduce the
alignment and padding to 64K.

Bspec: 45015
Fixes: 87bd701ee268 ("drm/i915: enforce min GTT alignment for discrete cards")
Signed-off-by: Matthew Auld 
Cc: Thomas Hellström 
Cc: Robert Beckett 
Cc: Ramalingam C 
---
 drivers/gpu/drm/i915/gt/intel_gtt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c 
b/drivers/gpu/drm/i915/gt/intel_gtt.c
index 4bcdfcab3642..a5f5b2dda332 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.c
@@ -234,7 +234,8 @@ void i915_address_space_init(struct i915_address_space *vm, 
int subclass)
memset64(vm->min_alignment, I915_GTT_MIN_ALIGNMENT,
 ARRAY_SIZE(vm->min_alignment));
 
-   if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915)) {
+   if (HAS_64K_PAGES(vm->i915) && NEEDS_COMPACT_PT(vm->i915) &&
+   subclass == VM_CLASS_PPGTT) {
vm->min_alignment[INTEL_MEMORY_LOCAL] = I915_GTT_PAGE_SIZE_2M;
vm->min_alignment[INTEL_MEMORY_STOLEN_LOCAL] = 
I915_GTT_PAGE_SIZE_2M;
} else if (HAS_64K_PAGES(vm->i915)) {
-- 
2.34.1