summaryrefslogtreecommitdiff
path: root/drivers/gpu
diff options
context:
space:
mode:
authorThierry Reding <treding@nvidia.com>2019-02-01 14:28:29 +0100
committerThierry Reding <treding@nvidia.com>2019-02-07 18:28:58 +0100
commit0e43b8da154a95f4369da4068a43ad9d700f4cea (patch)
tree25b86a7d2e0c567f2e4d77360fce720cc99519f9 /drivers/gpu
parent8de896eb206fea3caa26b5fc8e637934d8486f0f (diff)
gpu: host1x: Use correct semantics for HOST1X_CHANNEL_DMAEND
The HOST1X_CHANNEL_DMAEND is an offset relative to the value written to the HOST1X_CHANNEL_DMASTART register, but it is currently treated as an absolute address. This can cause SMMU faults if the CDMA fetches past a pushbuffer's IOMMU mapping. Properly setting the DMAEND prevents the CDMA from fetching beyond that address and avoid such issues. This is currently not observed because a whole (almost) page of essentially scratch space absorbs any excessive prefetching by CDMA. However, changing the number of slots in the push buffer can trigger these SMMU faults. Signed-off-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/host1x/hw/cdma_hw.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/host1x/hw/cdma_hw.c b/drivers/gpu/host1x/hw/cdma_hw.c
index 485aef5761af..a24c090ac96f 100644
--- a/drivers/gpu/host1x/hw/cdma_hw.c
+++ b/drivers/gpu/host1x/hw/cdma_hw.c
@@ -75,7 +75,7 @@ static void cdma_start(struct host1x_cdma *cdma)
cdma->last_pos = cdma->push_buffer.pos;
start = cdma->push_buffer.dma;
- end = start + cdma->push_buffer.size + 4;
+ end = cdma->push_buffer.size + 4;
host1x_ch_writel(ch, HOST1X_CHANNEL_DMACTRL_DMASTOP,
HOST1X_CHANNEL_DMACTRL);
@@ -126,7 +126,7 @@ static void cdma_timeout_restart(struct host1x_cdma *cdma, u32 getptr)
HOST1X_CHANNEL_DMACTRL);
start = cdma->push_buffer.dma;
- end = start + cdma->push_buffer.size + 4;
+ end = cdma->push_buffer.size + 4;
/* set base, end pointer (all of memory) */
host1x_ch_writel(ch, lower_32_bits(start), HOST1X_CHANNEL_DMASTART);