Commit 7c5cc941 authored by Imre Deak's avatar Imre Deak Committed by Daniel Vetter
Browse files

drm/i915/dg1: Reserve first 1MB of local memory 



On DG1 A0/B0 steppings the first 1MB of local memory must be reserved.
One reason for this is that the 0xA0000-0xB0000 range is not accessible
by the display, probably since this region is redirected to another
memory location for legacy VGA compatibility.

BSpec: 50586
Testcase: igt/kms_big_fb/linear-64bpp-rotate-0

v2:
- Reserve the memory on B0 as well.

v3: replace DRM_DEBUG/DRM_ERROR with drm_dbg/drm_err

v4: fix the insanity

Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
Signed-off-by: default avatarMatthew Auld <matthew.auld@intel.com>
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210127131417.393872-5-matthew.auld@intel.com


Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent adeca641

drivers/gpu/drm/i915/gt/intel_region_lmem.c

+41 −0
Original line number Diff line number Diff line
@@ -143,6 +143,38 @@ intel_gt_setup_fake_lmem(struct intel_gt *gt) 
	return mem;

}



static bool get_legacy_lowmem_region(struct intel_uncore *uncore,

				     u64 *start, u32 *size)

{

	if (!IS_DG1_REVID(uncore->i915, DG1_REVID_A0, DG1_REVID_B0))

		return false;



	*start = 0;

	*size = SZ_1M;



	drm_dbg(&uncore->i915->drm, "LMEM: reserved legacy low-memory [0x%llx-0x%llx]\n",

		*start, *start + *size);



	return true;

}



static int reserve_lowmem_region(struct intel_uncore *uncore,

				 struct intel_memory_region *mem)

{

	u64 reserve_start;

	u32 reserve_size;

	int ret;



	if (!get_legacy_lowmem_region(uncore, &reserve_start, &reserve_size))

		return 0;



	ret = intel_memory_region_reserve(mem, reserve_start, reserve_size);

	if (ret)

		drm_err(&uncore->i915->drm, "LMEM: reserving low memory region failed\n");



	return ret;

}



static struct intel_memory_region *setup_lmem(struct intel_gt *gt)

{

	struct drm_i915_private *i915 = gt->i915;
@@ -151,6 +183,7 @@ static struct intel_memory_region *setup_lmem(struct intel_gt *gt) 
	struct intel_memory_region *mem;

	resource_size_t io_start;

	resource_size_t lmem_size;

	int err;



	if (!IS_DGFX(i915))

		return ERR_PTR(-ENODEV);
@@ -171,6 +204,10 @@ static struct intel_memory_region *setup_lmem(struct intel_gt *gt) 
	if (IS_ERR(mem))

		return mem;



	err = reserve_lowmem_region(uncore, mem);

	if (err)

		goto err_region_put;



	drm_dbg(&i915->drm, "Local memory: %pR\n", &mem->region);

	drm_dbg(&i915->drm, "Local memory IO start: %pa\n",

		&mem->io_start);
@@ -178,6 +215,10 @@ static struct intel_memory_region *setup_lmem(struct intel_gt *gt) 
		 &lmem_size);



	return mem;



err_region_put:

	intel_memory_region_put(mem);

	return ERR_PTR(err);

}



struct intel_memory_region *intel_gt_setup_lmem(struct intel_gt *gt)