msm: kgsl: allow consistent CPU and GPU mappings
KGSL_GPUMEM_ALLOC_ID now takes a flag,
KGSL_MEMFLAGS_USE_CPU_MAP. When set, the GPU
mapping will be set up to match the CPU mapping
during mmap(). This feature is only supported when
using per process pagetables with the IOMMU. The
flags field of KGSL_GPUMEM_ALLOC_ID is copied back
to userspace and KGSL_MEMFLAGS_USE_CPU_MAP will
be cleared when this feature is not supported.
The IOMMU virtual address space has been adjusted
when perprocess pagetables is enabled so that the
entire userpace address range (0 to TASK_SIZE) can
have equivalent mappings on the IOMMU. For buffers
that do not have equivalent mappings, the address
range from PAGE_OFFSET to KGSL_IOMMU_GLOBAL_MEM_BASE
is used.
Change-Id: Ib61c03aa7453c3dd901c41e8fd297f66d402ae1a
Signed-off-by: Jeremy Gebben <jgebben@codeaurora.org>
diff --git a/include/linux/msm_kgsl.h b/include/linux/msm_kgsl.h
index ee136cac..4e62b4f 100644
--- a/include/linux/msm_kgsl.h
+++ b/include/linux/msm_kgsl.h
@@ -27,6 +27,7 @@
/* General allocation hints */
#define KGSL_MEMFLAGS_GPUREADONLY 0x01000000
+#define KGSL_MEMFLAGS_USE_CPU_MAP 0x10000000
/* Memory caching hints */
#define KGSL_CACHEMODE_MASK 0x0C000000
@@ -554,6 +555,8 @@
* KGSL_MEMFLAGS_GPUREADONLY: the GPU will be unable to write to the buffer
* KGSL_MEMTYPE*: usage hint for debugging aid
* KGSL_MEMALIGN*: alignment hint, may be ignored or adjusted by the kernel.
+ * KGSL_MEMFLAGS_USE_CPU_MAP: If set on call and return, the returned GPU
+ * address will be 0. Calling mmap() will set the GPU address.
*/
struct kgsl_gpumem_alloc_id {
unsigned int id;