This is a note to let you know that I've just added the patch titled
drm/amdgpu: use polling mem to set SDMA3 wptr for VF
to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amdgpu-use-polling-mem-to-set-sdma3-wptr-for-vf.patch
and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Mar 22 14:03:39 CET 2018
From: Pixel Ding <Pixel.Ding@xxxxxxx>
Date: Mon, 11 Dec 2017 16:48:33 +0800
Subject: drm/amdgpu: use polling mem to set SDMA3 wptr for VF
From: Pixel Ding <Pixel.Ding@xxxxxxx>
[ Upstream commit 2ffe31deb27579e2f2c9444e01f4d8abf385d145 ]
On Tonga VF, there're 2 sources updating wptr registers for
sdma3: 1) polling mem and 2) doorbell. When doorbell and polling
mem are both enabled on sdma3, there will be collision hit in
occasion between those two sources when ucode and h/w are doing
the updating on wptr register in parallel. Issue doesn't happen
on CP GFX/Compute since CP drops all doorbell writes when VF is
inactive. So enable polling mem and don't use doorbell for SDMA3.
Signed-off-by: Pixel Ding <Pixel.Ding@xxxxxxx>
Reviewed-by: Monk Liu <monk.liu@xxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h | 1 +
drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c | 27 +++++++++++++++++++--------
2 files changed, 20 insertions(+), 8 deletions(-)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
@@ -187,6 +187,7 @@ struct amdgpu_ring {
uint64_t eop_gpu_addr;
u32 doorbell_index;
bool use_doorbell;
+ bool use_pollmem;
unsigned wptr_offs;
unsigned fence_offs;
uint64_t current_ctx;
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
@@ -355,7 +355,7 @@ static uint64_t sdma_v3_0_ring_get_wptr(
struct amdgpu_device *adev = ring->adev;
u32 wptr;
- if (ring->use_doorbell) {
+ if (ring->use_doorbell || ring->use_pollmem) {
/* XXX check if swapping is necessary on BE */
wptr = ring->adev->wb.wb[ring->wptr_offs] >> 2;
} else {
@@ -380,10 +380,13 @@ static void sdma_v3_0_ring_set_wptr(stru
if (ring->use_doorbell) {
u32 *wb = (u32 *)&adev->wb.wb[ring->wptr_offs];
-
/* XXX check if swapping is necessary on BE */
WRITE_ONCE(*wb, (lower_32_bits(ring->wptr) << 2));
WDOORBELL32(ring->doorbell_index, lower_32_bits(ring->wptr) << 2);
+ } else if (ring->use_pollmem) {
+ u32 *wb = (u32 *)&adev->wb.wb[ring->wptr_offs];
+
+ WRITE_ONCE(*wb, (lower_32_bits(ring->wptr) << 2));
} else {
int me = (ring == &ring->adev->sdma.instance[0].ring) ? 0 : 1;
@@ -718,10 +721,14 @@ static int sdma_v3_0_gfx_resume(struct a
WREG32(mmSDMA0_GFX_RB_WPTR_POLL_ADDR_HI + sdma_offsets[i],
upper_32_bits(wptr_gpu_addr));
wptr_poll_cntl = RREG32(mmSDMA0_GFX_RB_WPTR_POLL_CNTL + sdma_offsets[i]);
- if (amdgpu_sriov_vf(adev))
- wptr_poll_cntl = REG_SET_FIELD(wptr_poll_cntl, SDMA0_GFX_RB_WPTR_POLL_CNTL, F32_POLL_ENABLE, 1);
+ if (ring->use_pollmem)
+ wptr_poll_cntl = REG_SET_FIELD(wptr_poll_cntl,
+ SDMA0_GFX_RB_WPTR_POLL_CNTL,
+ ENABLE, 1);
else
- wptr_poll_cntl = REG_SET_FIELD(wptr_poll_cntl, SDMA0_GFX_RB_WPTR_POLL_CNTL, F32_POLL_ENABLE, 0);
+ wptr_poll_cntl = REG_SET_FIELD(wptr_poll_cntl,
+ SDMA0_GFX_RB_WPTR_POLL_CNTL,
+ ENABLE, 0);
WREG32(mmSDMA0_GFX_RB_WPTR_POLL_CNTL + sdma_offsets[i], wptr_poll_cntl);
/* enable DMA RB */
@@ -1203,9 +1210,13 @@ static int sdma_v3_0_sw_init(void *handl
for (i = 0; i < adev->sdma.num_instances; i++) {
ring = &adev->sdma.instance[i].ring;
ring->ring_obj = NULL;
- ring->use_doorbell = true;
- ring->doorbell_index = (i == 0) ?
- AMDGPU_DOORBELL_sDMA_ENGINE0 : AMDGPU_DOORBELL_sDMA_ENGINE1;
+ if (!amdgpu_sriov_vf(adev)) {
+ ring->use_doorbell = true;
+ ring->doorbell_index = (i == 0) ?
+ AMDGPU_DOORBELL_sDMA_ENGINE0 : AMDGPU_DOORBELL_sDMA_ENGINE1;
+ } else {
+ ring->use_pollmem = true;
+ }
sprintf(ring->name, "sdma%d", i);
r = amdgpu_ring_init(adev, ring, 1024,
Patches currently in stable-queue which might be from Pixel.Ding@xxxxxxx are
queue-4.15/drm-amdgpu-use-polling-mem-to-set-sdma3-wptr-for-vf.patch