drm/i915: support forcing the page size with lmem

For some specialised objects we might need something larger than the
regions min_page_size due to some hw restriction, and slightly more
hairy is needing something smaller with the guarantee that such objects
will never be inserted into any GTT, which is the case for the paging
structures.

This also fixes how we setup the BO page_alignment, if we later migrate
the object somewhere else. For example if the placements are {SMEM,
LMEM}, then we might get this wrong. Pushing the min_page_size behaviour
into the manager should fix this.

v2(Thomas): push the default page size behaviour into buddy_man, and let
the user override it with the page-alignment, which looks cleaner

v3: rebase on ttm sys changes

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625103824.558481-1-matthew.auld@intel.com

2 files changed, 61 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
index ecc3b9e6c22b..1aaccb9841a0 100644
--- a/drivers/gpu/drm/i915/selftests/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
@@ -68,7 +68,7 @@ static int igt_mock_fill(void *arg)
 		resource_size_t size = page_num * page_size;
 		struct drm_i915_gem_object *obj;
 
-		obj = i915_gem_object_create_region(mem, size, 0);
+		obj = i915_gem_object_create_region(mem, size, 0, 0);
 		if (IS_ERR(obj)) {
 			err = PTR_ERR(obj);
 			break;
@@ -110,7 +110,7 @@ igt_object_create(struct intel_memory_region *mem,
 	struct drm_i915_gem_object *obj;
 	int err;
 
-	obj = i915_gem_object_create_region(mem, size, flags);
+	obj = i915_gem_object_create_region(mem, size, 0, flags);
 	if (IS_ERR(obj))
 		return obj;
 
@@ -647,6 +647,62 @@ out_put:
 	return err;
 }
 
+static int igt_lmem_create_with_ps(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	int err = 0;
+	u32 ps;
+
+	for (ps = PAGE_SIZE; ps <= SZ_1G; ps <<= 1) {
+		struct drm_i915_gem_object *obj;
+		dma_addr_t daddr;
+
+		obj = __i915_gem_object_create_lmem_with_ps(i915, ps, ps, 0);
+		if (IS_ERR(obj)) {
+			err = PTR_ERR(obj);
+			if (err == -ENXIO || err == -E2BIG) {
+				pr_info("%s not enough lmem for ps(%u) err=%d\n",
+					__func__, ps, err);
+				err = 0;
+			}
+
+			break;
+		}
+
+		if (obj->base.size != ps) {
+			pr_err("%s size(%zu) != ps(%u)\n",
+			       __func__, obj->base.size, ps);
+			err = -EINVAL;
+			goto out_put;
+		}
+
+		i915_gem_object_lock(obj, NULL);
+		err = i915_gem_object_pin_pages(obj);
+		if (err)
+			goto out_put;
+
+		daddr = i915_gem_object_get_dma_address(obj, 0);
+		if (!IS_ALIGNED(daddr, ps)) {
+			pr_err("%s daddr(%pa) not aligned with ps(%u)\n",
+			       __func__, &daddr, ps);
+			err = -EINVAL;
+			goto out_unpin;
+		}
+
+out_unpin:
+		i915_gem_object_unpin_pages(obj);
+		__i915_gem_object_put_pages(obj);
+out_put:
+		i915_gem_object_unlock(obj);
+		i915_gem_object_put(obj);
+
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
 static int igt_lmem_create_cleared_cpu(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
@@ -932,7 +988,7 @@ create_region_for_mapping(struct intel_memory_region *mr, u64 size, u32 type,
 	struct drm_i915_gem_object *obj;
 	void *addr;
 
-	obj = i915_gem_object_create_region(mr, size, 0);
+	obj = i915_gem_object_create_region(mr, size, 0, 0);
 	if (IS_ERR(obj)) {
 		if (PTR_ERR(obj) == -ENOSPC) /* Stolen memory */
 			return ERR_PTR(-ENODEV);
@@ -1149,6 +1205,7 @@ int intel_memory_region_live_selftests(struct drm_i915_private *i915)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(igt_lmem_create),
+		SUBTEST(igt_lmem_create_with_ps),
 		SUBTEST(igt_lmem_create_cleared_cpu),
 		SUBTEST(igt_lmem_write_cpu),
 		SUBTEST(igt_lmem_write_gpu),
diff --git a/drivers/gpu/drm/i915/selftests/mock_region.c b/drivers/gpu/drm/i915/selftests/mock_region.c
index fa786dede608..efa86dffe3c6 100644
--- a/drivers/gpu/drm/i915/selftests/mock_region.c
+++ b/drivers/gpu/drm/i915/selftests/mock_region.c
@@ -63,6 +63,7 @@ static const struct drm_i915_gem_object_ops mock_region_obj_ops = {
 static int mock_object_init(struct intel_memory_region *mem,
 			    struct drm_i915_gem_object *obj,
 			    resource_size_t size,
+			    resource_size_t page_size,
 			    unsigned int flags)
 {
 	static struct lock_class_key lock_class;