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/drivers/gpu/msm/kgsl_mmu.h b/drivers/gpu/msm/kgsl_mmu.h
index bf330ee..9d1bffa 100644
--- a/drivers/gpu/msm/kgsl_mmu.h
+++ b/drivers/gpu/msm/kgsl_mmu.h
@@ -19,11 +19,10 @@
* These defines control the address range for allocations that
* are mapped into all pagetables.
*/
-#define KGSL_IOMMU_GLOBAL_MEM_BASE 0xC0000000
+#define KGSL_IOMMU_GLOBAL_MEM_BASE 0xf8000000
#define KGSL_IOMMU_GLOBAL_MEM_SIZE SZ_4M
-#define KGSL_MMU_ALIGN_SHIFT 13
-#define KGSL_MMU_ALIGN_MASK (~((1 << KGSL_MMU_ALIGN_SHIFT) - 1))
+#define KGSL_MMU_ALIGN_MASK (~((1 << PAGE_SHIFT) - 1))
/* Identifier for the global page table */
/* Per process page tables will probably pass in the thread group
@@ -381,32 +380,52 @@
/*
* kgsl_mmu_base_addr() - Get gpu virtual address base.
*
- * Returns the start address of the gpu
- * virtual address space.
+ * Returns the start address of the allocatable gpu
+ * virtual address space. Other mappings that mirror
+ * the CPU address space are possible outside this range.
*/
static inline unsigned int kgsl_mmu_get_base_addr(void)
{
- return KGSL_PAGETABLE_BASE;
+ if (KGSL_MMU_TYPE_GPU == kgsl_mmu_get_mmutype()
+ || !kgsl_mmu_is_perprocess())
+ return KGSL_PAGETABLE_BASE;
+ /*
+ * This is the start of the kernel address
+ * space, so allocations from this range will
+ * never conflict with userpace addresses
+ */
+ return PAGE_OFFSET;
}
/*
* kgsl_mmu_get_ptsize() - Get gpu pagetable size
*
- * Returns the usable size of the gpu address space.
+ * Returns the usable size of the gpu allocatable
+ * address space.
*/
static inline unsigned int kgsl_mmu_get_ptsize(void)
{
/*
- * For IOMMU, we could do up to 4G virtual range if we wanted to, but
- * it makes more sense to return a smaller range and leave the rest of
- * the virtual range for future improvements
+ * For IOMMU per-process pagetables, the allocatable range
+ * and the kernel global range must both be outside
+ * the userspace address range. There is a 1Mb gap
+ * between these address ranges to make overrun
+ * detection easier.
+ * For the shared pagetable case use 2GB and because
+ * mirroring the CPU address space is not possible and
+ * we're better off with extra room.
*/
enum kgsl_mmutype mmu_type = kgsl_mmu_get_mmutype();
if (KGSL_MMU_TYPE_GPU == mmu_type)
return CONFIG_MSM_KGSL_PAGE_TABLE_SIZE;
- else if (KGSL_MMU_TYPE_IOMMU == mmu_type)
- return SZ_2G;
+ else if (KGSL_MMU_TYPE_IOMMU == mmu_type) {
+ if (kgsl_mmu_is_perprocess())
+ return KGSL_IOMMU_GLOBAL_MEM_BASE
+ - kgsl_mmu_get_base_addr() - SZ_1M;
+ else
+ return SZ_2G;
+ }
return 0;
}