[PATCH v9 13/15] drm/msm: Add wait-boost support

Rob Clark
2023-03-02T23:55:14Z

From: Rob Clark <robdclark@chromium.org>

Add a way for various userspace waits to signal urgency.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
drivers/gpu/drm/msm/msm_drv.c | 12 ++++++++----
drivers/gpu/drm/msm/msm_gem.c | 5 +++++
include/uapi/drm/msm_drm.h | 14 ++++++++++++--
3 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index aca48c868c14..f6764a86b2da 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -46,6 +46,7 @@
* - 1.8.0 - Add MSM_BO_CACHED_COHERENT for supported GPUs (a6xx)
* - 1.9.0 - Add MSM_SUBMIT_FENCE_SN_IN
* - 1.10.0 - Add MSM_SUBMIT_BO_NO_IMPLICIT
+ * - 1.11.0 - Add wait boost (MSM_WAIT_FENCE_BOOST, MSM_PREP_BOOST)
*/
#define MSM_VERSION_MAJOR 1
#define MSM_VERSION_MINOR 10
@@ -899,7 +900,7 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data,
}

static int wait_fence(struct msm_gpu_submitqueue *queue, uint32_t fence_id,
- ktime_t timeout)
+ ktime_t timeout, uint32_t flags)
{
struct dma_fence *fence;
int ret;
@@ -929,6 +930,9 @@ static int wait_fence(struct msm_gpu_submitqueue *queue, uint32_t fence_id,
if (!fence)
return 0;

+ if (flags & MSM_WAIT_FENCE_BOOST)
+ dma_fence_set_deadline(fence, ktime_get());
+
ret = dma_fence_wait_timeout(fence, true, timeout_to_jiffies(&timeout));
if (ret == 0) {
ret = -ETIMEDOUT;
@@ -949,8 +953,8 @@ static int msm_ioctl_wait_fence(struct drm_device *dev, void *data,
struct msm_gpu_submitqueue *queue;
int ret;

- if (args->pad) {
- DRM_ERROR("invalid pad: %08x\n", args->pad);
+ if (args->flags & ~MSM_WAIT_FENCE_FLAGS) {
+ DRM_ERROR("invalid flags: %08x\n", args->flags);
return -EINVAL;
}

@@ -961,7 +965,7 @@ static int msm_ioctl_wait_fence(struct drm_device *dev, void *data,
if (!queue)
return -ENOENT;

- ret = wait_fence(queue, args->fence, to_ktime(args->timeout));
+ ret = wait_fence(queue, args->fence, to_ktime(args->timeout), args->flags);

msm_submitqueue_put(queue);

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 1dee0d18abbb..dd4a0d773f6e 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -846,6 +846,11 @@ int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
op & MSM_PREP_NOSYNC ? 0 : timeout_to_jiffies(timeout);
long ret;

+ if (op & MSM_PREP_BOOST) {
+ dma_resv_set_deadline(obj->resv, dma_resv_usage_rw(write),
+ ktime_get());
+ }
+
ret = dma_resv_wait_timeout(obj->resv, dma_resv_usage_rw(write),
true, remain);
if (ret == 0)
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
index 329100016e7c..dbf0d6f43fa9 100644
--- a/include/uapi/drm/msm_drm.h
+++ b/include/uapi/drm/msm_drm.h
@@ -151,8 +151,13 @@ struct drm_msm_gem_info {
#define MSM_PREP_READ 0x01
#define MSM_PREP_WRITE 0x02
#define MSM_PREP_NOSYNC 0x04
+#define MSM_PREP_BOOST 0x08

-#define MSM_PREP_FLAGS (MSM_PREP_READ | MSM_PREP_WRITE | MSM_PREP_NOSYNC)
+#define MSM_PREP_FLAGS (MSM_PREP_READ | \
+ MSM_PREP_WRITE | \
+ MSM_PREP_NOSYNC | \
+ MSM_PREP_BOOST | \
+ 0)

struct drm_msm_gem_cpu_prep {
__u32 handle; /* in */
@@ -286,6 +291,11 @@ struct drm_msm_gem_submit {

};

+#define MSM_WAIT_FENCE_BOOST 0x00000001
+#define MSM_WAIT_FENCE_FLAGS ( \
+ MSM_WAIT_FENCE_BOOST | \
+ 0)
+
/* The normal way to synchronize with the GPU is just to CPU_PREP on
* a buffer if you need to access it from the CPU (other cmdstream
* submission from same or other contexts, PAGE_FLIP ioctl, etc, all
@@ -295,7 +305,7 @@ struct drm_msm_gem_submit {
*/
struct drm_msm_wait_fence {
__u32 fence; /* in */
- __u32 pad;
+ __u32 flags; /* in, bitmask of MSM_WAIT_FENCE_x */
struct drm_msm_timespec timeout; /* in */
__u32 queueid; /* in, submitqueue id */
};
--
2.39.1