[Intel-gfx] [RFC PATCH 10/42] drm/i915/lmem: add helper to get CPU visible pfn

[Matthew Auld]

From: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>

Signed-off-by: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_region_lmem.c | 11 +++++++++++
 drivers/gpu/drm/i915/intel_region_lmem.h |  3 +++
 2 files changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_region_lmem.c b/drivers/gpu/drm/i915/intel_region_lmem.c
index 4a205639cbb6..b398becb2733 100644
--- a/drivers/gpu/drm/i915/intel_region_lmem.c
+++ b/drivers/gpu/drm/i915/intel_region_lmem.c
@@ -65,6 +65,17 @@ static const struct intel_memory_region_ops region_lmem_ops = {
 	.object_create = region_lmem_object_create,
 };
 
+unsigned long i915_gem_object_lmem_io_pfn(struct drm_i915_gem_object *obj,
+					  unsigned long n)
+{
+	struct intel_memory_region *mem = obj->memory_region;
+	resource_size_t offset;
+
+	offset = i915_gem_object_get_dma_address(obj, n);
+
+	return (mem->io_start + offset) >> PAGE_SHIFT;
+}
+
 bool i915_gem_object_is_lmem(struct drm_i915_gem_object *obj)
 {
 	struct intel_memory_region *region = obj->memory_region;
diff --git a/drivers/gpu/drm/i915/intel_region_lmem.h b/drivers/gpu/drm/i915/intel_region_lmem.h
index 7204f61aab44..1aa24bd28690 100644
--- a/drivers/gpu/drm/i915/intel_region_lmem.h
+++ b/drivers/gpu/drm/i915/intel_region_lmem.h
@@ -25,6 +25,9 @@
 #ifndef __INTEL_REGION_LMEM_H
 #define __INTEL_REGION_LMEM_H
 
+unsigned long i915_gem_object_lmem_io_pfn(struct drm_i915_gem_object *obj,
+					  unsigned long n);
+
 bool i915_gem_object_is_lmem(struct drm_i915_gem_object *obj);
 
 struct drm_i915_gem_object *
-- 
2.20.1