In order to support performance counters in a sane way we need to provide a method to sync the GPU with the CPU. The GPU can process multpile command buffers/events per irq. With the help of a 'sync point' we can trigger an event and stop the GPU/FE immediately. When the CPU is done with is processing it simply needs to restart the FE and the GPU will process the command stream.
Changes from v1 -> v2: - process sync point with a work item to keep irq as fast as possible
Changes from v4 -> v5: - renamed pmrs_* to sync_point_* - call event_free(..) in sync_point_worker(..)
Signed-off-by: Christian Gmeiner christian.gmeiner@gmail.com --- drivers/gpu/drm/etnaviv/etnaviv_buffer.c | 36 ++++++++++++++++++++++++++++++++ drivers/gpu/drm/etnaviv/etnaviv_drv.h | 1 + drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 26 +++++++++++++++++++++++ drivers/gpu/drm/etnaviv/etnaviv_gpu.h | 6 ++++++ 4 files changed, 69 insertions(+)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c index ed9588f36bc9..9e7098e3207f 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c @@ -250,6 +250,42 @@ void etnaviv_buffer_end(struct etnaviv_gpu *gpu) } }
+/* Append a 'sync point' to the ring buffer. */ +void etnaviv_sync_point_queue(struct etnaviv_gpu *gpu, unsigned int event) +{ + struct etnaviv_cmdbuf *buffer = gpu->buffer; + unsigned int waitlink_offset = buffer->user_size - 16; + u32 dwords, target; + + /* + * We need at most 3 dwords in the return target: + * 1 event + 1 end + 1 wait + 1 link. + */ + dwords = 4; + target = etnaviv_buffer_reserve(gpu, buffer, dwords); + + /* Signal sync point event */ + CMD_LOAD_STATE(buffer, VIVS_GL_EVENT, VIVS_GL_EVENT_EVENT_ID(event) | + VIVS_GL_EVENT_FROM_PE); + + /* Stop the FE to 'pause' the GPU */ + CMD_END(buffer); + + /* Append waitlink */ + CMD_WAIT(buffer); + CMD_LINK(buffer, 2, etnaviv_cmdbuf_get_va(buffer) + + buffer->user_size - 4); + + /* + * Kick off the 'sync point' command by replacing the previous + * WAIT with a link to the address in the ring buffer. + */ + etnaviv_buffer_replace_wait(buffer, waitlink_offset, + VIV_FE_LINK_HEADER_OP_LINK | + VIV_FE_LINK_HEADER_PREFETCH(dwords), + target); +} + /* Append a command buffer to the ring buffer. */ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, unsigned int event, struct etnaviv_cmdbuf *cmdbuf) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h index 058389f93b69..f6cdd694ca51 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h @@ -101,6 +101,7 @@ int etnaviv_gem_new_userptr(struct drm_device *dev, struct drm_file *file, u16 etnaviv_buffer_init(struct etnaviv_gpu *gpu); u16 etnaviv_buffer_config_mmuv2(struct etnaviv_gpu *gpu, u32 mtlb_addr, u32 safe_addr); void etnaviv_buffer_end(struct etnaviv_gpu *gpu); +void etnaviv_sync_point_queue(struct etnaviv_gpu *gpu, unsigned int event); void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, unsigned int event, struct etnaviv_cmdbuf *cmdbuf); void etnaviv_validate_init(void); diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index 9372296b5b9c..cdb67026729f 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -25,6 +25,7 @@ #include "etnaviv_gpu.h" #include "etnaviv_gem.h" #include "etnaviv_mmu.h" +#include "etnaviv_perfmon.h" #include "common.xml.h" #include "state.xml.h" #include "state_hi.xml.h" @@ -1359,6 +1360,7 @@ int etnaviv_gpu_submit(struct etnaviv_gpu *gpu, }
gpu->event[event].fence = fence; + gpu->event[event].sync_point = NULL; submit->fence = dma_fence_get(fence); gpu->active_fence = submit->fence->seqno;
@@ -1404,6 +1406,24 @@ int etnaviv_gpu_submit(struct etnaviv_gpu *gpu, return ret; }
+static void etnaviv_process_sync_point(struct etnaviv_gpu *gpu, + struct etnaviv_event *event) +{ + u32 addr = gpu_read(gpu, VIVS_FE_DMA_ADDRESS); + + event->sync_point(gpu, event); + etnaviv_gpu_start_fe(gpu, addr + 2, 2); +} + +static void sync_point_worker(struct work_struct *work) +{ + struct etnaviv_gpu *gpu = container_of(work, struct etnaviv_gpu, + sync_point_work); + + etnaviv_process_sync_point(gpu, &gpu->event[gpu->sync_point_event]); + event_free(gpu, gpu->sync_point_event); +} + /* * Init/Cleanup: */ @@ -1450,6 +1470,11 @@ static irqreturn_t irq_handler(int irq, void *data)
dev_dbg(gpu->dev, "event %u\n", event);
+ if (gpu->event[event].sync_point) { + gpu->sync_point_event = event; + etnaviv_queue_work(gpu->drm, &gpu->sync_point_work); + } + fence = gpu->event[event].fence; gpu->event[event].fence = NULL; dma_fence_signal(fence); @@ -1653,6 +1678,7 @@ static int etnaviv_gpu_bind(struct device *dev, struct device *master,
INIT_LIST_HEAD(&gpu->active_cmd_list); INIT_WORK(&gpu->retire_work, retire_worker); + INIT_WORK(&gpu->sync_point_work, sync_point_worker); INIT_WORK(&gpu->recover_work, recover_worker); init_waitqueue_head(&gpu->fence_event);
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h index 70e6590aacdf..3be5cb53e89f 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h @@ -89,6 +89,8 @@ struct etnaviv_chip_identity {
struct etnaviv_event { struct dma_fence *fence; + + void (*sync_point)(struct etnaviv_gpu *gpu, struct etnaviv_event *event); };
struct etnaviv_cmdbuf_suballoc; @@ -135,6 +137,10 @@ struct etnaviv_gpu { /* worker for handling active-list retiring: */ struct work_struct retire_work;
+ /* worker for handling 'sync' points: */ + struct work_struct sync_point_work; + int sync_point_event; + void __iomem *mmio; int irq;