[PATCH 25/48] staging: etnaviv: increase page table size to maximum

[Lucas Stach]

From: Russell King <rmk+kernel at arm.linux.org.uk>

Running the cairo trace "firefox-36-20090609" results in the Xorg server
trying to queue up 319M of buffer objects in a single commit (due to the
number of drawing operations that will fit into a 32K command buffer.)
This causes the commit ioctl to return -ENOSPC as the MMU is unable to
map all these buffer objects simultaneously.

There are three workarounds possible:
- Increase the GPU MMU table size
- Decrease the command buffer size
- Implement reconstruction of the command buffer on -ENOSPC return

All three should be implemented, but the first is only applicable to the
kernel.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
 drivers/staging/etnaviv/etnaviv_iommu.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/etnaviv/etnaviv_iommu.c b/drivers/staging/etnaviv/etnaviv_iommu.c
index 73ba65205705..9efb7d6092b4 100644
--- a/drivers/staging/etnaviv/etnaviv_iommu.c
+++ b/drivers/staging/etnaviv/etnaviv_iommu.c
@@ -25,7 +25,7 @@
 #include "etnaviv_iommu.h"
 #include "state_hi.xml.h"
 
-#define PT_SIZE		SZ_512K
+#define PT_SIZE		SZ_2M
 #define PT_ENTRIES	(PT_SIZE / sizeof(u32))
 
 #define GPU_MEM_START	0x80000000
@@ -88,7 +88,7 @@ static void pgtable_write(struct etnaviv_iommu_domain_pgtable *pgtable,
 
 static int __etnaviv_iommu_init(struct etnaviv_iommu_domain *etnaviv_domain)
 {
-	u32 iova, *p;
+	u32 *p;
 	int ret, i;
 
 	etnaviv_domain->bad_page_cpu = dma_alloc_coherent(etnaviv_domain->dev,
@@ -110,11 +110,9 @@ static int __etnaviv_iommu_init(struct etnaviv_iommu_domain *etnaviv_domain)
 		return ret;
 	}
 
-	for (iova = etnaviv_domain->domain.geometry.aperture_start;
-	     iova < etnaviv_domain->domain.geometry.aperture_end; iova += SZ_4K) {
-		pgtable_write(&etnaviv_domain->pgtable, iova,
-			      etnaviv_domain->bad_page_dma);
-	}
+	for (i = 0; i < PT_ENTRIES; i++)
+		etnaviv_domain->pgtable.pgtable[i] =
+			etnaviv_domain->bad_page_dma;
 
 	spin_lock_init(&etnaviv_domain->map_lock);
 
-- 
2.5.1