[PATCH 1/3] TILER: Move dma_alloc_coherent call to tiler init

[Bryan Wu]

From: David Sin <davidsin at ti.com>

Instead of allocating and freeing PAT page array
memory each time, allocate 128k upfront and reuse the
memory.  This will avoid the possibilty of not being
able to obtain the memory after driver initialization.

Signed-off-by: David Sin <davidsin at ti.com>
---
 drivers/media/video/tiler/tiler.c |   27 +++++++++++++++------------
 1 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/media/video/tiler/tiler.c b/drivers/media/video/tiler/tiler.c
index c8008b0..bd35248 100644
--- a/drivers/media/video/tiler/tiler.c
+++ b/drivers/media/video/tiler/tiler.c
@@ -120,6 +120,8 @@ static u32 id;
 static struct mutex mtx;
 static struct tcm *tcm[TILER_FORMATS];
 static struct tmm *tmm[TILER_FORMATS];
+static u32 *dmac_va;
+static dma_addr_t dmac_pa;
 
 #define TCM(fmt)        tcm[(fmt) - TILFMT_8BIT]
 #define TCM_SS(ssptr)   TCM(TILER_GET_ACC_MODE(ssptr))
@@ -829,34 +831,24 @@ static s32 tiler_mmap(struct file *filp, struct vm_area_struct *vma)
 static s32 refill_pat(struct tmm *tmm, struct tcm_area *area, u32 *ptr)
 {
 	s32 res = 0;
-	s32 size = tcm_sizeof(*area) * sizeof(*ptr);
-	u32 *page;
-	dma_addr_t page_pa;
 	struct pat_area p_area = {0};
 	struct tcm_area slice, area_s;
 
-	/* must be a 16-byte aligned physical address */
-	page = dma_alloc_coherent(NULL, size, &page_pa, GFP_ATOMIC);
-	if (!page)
-		return -ENOMEM;
-
 	tcm_for_each_slice(slice, *area, area_s) {
 		p_area.x0 = slice.p0.x;
 		p_area.y0 = slice.p0.y;
 		p_area.x1 = slice.p1.x;
 		p_area.y1 = slice.p1.y;
 
-		memcpy(page, ptr, sizeof(*ptr) * tcm_sizeof(slice));
+		memcpy(dmac_va, ptr, sizeof(*ptr) * tcm_sizeof(slice));
 		ptr += tcm_sizeof(slice);
 
-		if (tmm_map(tmm, p_area, page_pa)) {
+		if (tmm_map(tmm, p_area, dmac_pa)) {
 			res = -EFAULT;
 			break;
 		}
 	}
 
-	dma_free_coherent(NULL, size, page, page_pa);
-
 	return res;
 }
 
@@ -1423,6 +1415,9 @@ static void __exit tiler_exit(void)
 
 	mutex_unlock(&mtx);
 
+	dma_free_coherent(NULL, TILER_WIDTH * TILER_HEIGHT * sizeof(*dmac_va),
+							dmac_va, dmac_pa);
+
 	/* close containers only once */
 	for (i = TILFMT_8BIT; i <= TILFMT_MAX; i++) {
 		/* remove identical containers (tmm is unique per tcm) */
@@ -1502,6 +1497,14 @@ static s32 __init tiler_init(void)
 	TMM_SET(TILFMT_32BIT, tmm_pat);
 	TMM_SET(TILFMT_PAGE, tmm_pat);
 
+	/* Array of physical pages for PAT programming, which must be a 16-byte
+	   aligned physical address
+	*/
+	dmac_va = dma_alloc_coherent(NULL, TILER_WIDTH * TILER_HEIGHT *
+					sizeof(*dmac_va), &dmac_pa, GFP_ATOMIC);
+	if (!dmac_va)
+		return -ENOMEM;
+
 	tiler_device = kmalloc(sizeof(*tiler_device), GFP_KERNEL);
 	if (!tiler_device || !sita || !tmm_pat) {
 		r = -ENOMEM;
-- 
1.7.0.4