On 03/10/2014 10:47 AM, Rob Clark wrote:
Shut down the clks when the gpu has nothing to do. A short inactivity timer is used to provide a low pass filter for power transitions.
Good luck. Power management will take years off your life.
Signed-off-by: Rob Clark <robdclark@xxxxxxxxx>
Acked-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
--- drivers/gpu/drm/msm/adreno/a3xx_gpu.c | 10 +++++ drivers/gpu/drm/msm/msm_drv.c | 7 ++- drivers/gpu/drm/msm/msm_gpu.c | 85 +++++++++++++++++++++++++++++++++-- drivers/gpu/drm/msm/msm_gpu.h | 16 ++++++- 4 files changed, 113 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c index 59ed762..e6cb2bc 100644 --- a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c @@ -395,9 +395,15 @@ static const unsigned int a3xx_registers[] = { #ifdef CONFIG_DEBUG_FS static void a3xx_show(struct msm_gpu *gpu, struct seq_file *m) { + struct drm_device *dev = gpu->dev; int i; adreno_show(gpu, m); + + mutex_lock(&dev->struct_mutex); + + gpu->funcs->pm_resume(gpu); + seq_printf(m, "status: %08x\n", gpu_read(gpu, REG_A3XX_RBBM_STATUS)); @@ -413,6 +419,10 @@ static void a3xx_show(struct msm_gpu *gpu, struct seq_file *m) seq_printf(m, "IO:R %08x %08x\n", addr<<2, val); } } + + gpu->funcs->pm_suspend(gpu); + + mutex_unlock(&dev->struct_mutex); } #endif diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index e6adafc..e913efa 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -311,7 +311,6 @@ static void load_gpu(struct drm_device *dev) gpu = NULL; /* not fatal */ } - mutex_unlock(&dev->struct_mutex); if (gpu) { int ret; @@ -321,10 +320,16 @@ static void load_gpu(struct drm_device *dev) dev_err(dev->dev, "gpu hw init failed: %d\n", ret); gpu->funcs->destroy(gpu); gpu = NULL; + } else { + /* give inactive pm a chance to kick in: */ + msm_gpu_retire(gpu); } + } priv->gpu = gpu; + + mutex_unlock(&dev->struct_mutex); } static int msm_open(struct drm_device *dev, struct drm_file *file) diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c index 0cfe3f4..3e667ca 100644 --- a/drivers/gpu/drm/msm/msm_gpu.c +++ b/drivers/gpu/drm/msm/msm_gpu.c @@ -154,9 +154,18 @@ static int disable_axi(struct msm_gpu *gpu) int msm_gpu_pm_resume(struct msm_gpu *gpu) { + struct drm_device *dev = gpu->dev; int ret; - DBG("%s", gpu->name); + DBG("%s: active_cnt=%d", gpu->name, gpu->active_cnt); + + WARN_ON(!mutex_is_locked(&dev->struct_mutex)); + + if (gpu->active_cnt++ > 0) + return 0; + + if (WARN_ON(gpu->active_cnt <= 0)) + return -EINVAL; ret = enable_pwrrail(gpu); if (ret) @@ -175,9 +184,18 @@ int msm_gpu_pm_resume(struct msm_gpu *gpu) int msm_gpu_pm_suspend(struct msm_gpu *gpu) { + struct drm_device *dev = gpu->dev; int ret; - DBG("%s", gpu->name); + DBG("%s: active_cnt=%d", gpu->name, gpu->active_cnt); + + WARN_ON(!mutex_is_locked(&dev->struct_mutex)); + + if (--gpu->active_cnt > 0) + return 0; + + if (WARN_ON(gpu->active_cnt < 0)) + return -EINVAL; ret = disable_axi(gpu); if (ret) @@ -195,6 +213,55 @@ int msm_gpu_pm_suspend(struct msm_gpu *gpu) } /* + * Inactivity detection (for suspend): + */ + +static void inactive_worker(struct work_struct *work) +{ + struct msm_gpu *gpu = container_of(work, struct msm_gpu, inactive_work); + struct drm_device *dev = gpu->dev; + + if (gpu->inactive) + return; + + DBG("%s: inactive!\n", gpu->name); + mutex_lock(&dev->struct_mutex); + if (!(msm_gpu_active(gpu) || gpu->inactive)) { + disable_axi(gpu); + disable_clk(gpu); + gpu->inactive = true; + } + mutex_unlock(&dev->struct_mutex); +} + +static void inactive_handler(unsigned long data) +{ + struct msm_gpu *gpu = (struct msm_gpu *)data; + struct msm_drm_private *priv = gpu->dev->dev_private; + + queue_work(priv->wq, &gpu->inactive_work); +} + +/* cancel inactive timer and make sure we are awake: */ +static void inactive_cancel(struct msm_gpu *gpu) +{ + DBG("%s", gpu->name); + del_timer(&gpu->inactive_timer); + if (gpu->inactive) { + enable_clk(gpu); + enable_axi(gpu); + gpu->inactive = false; + } +} + +static void inactive_start(struct msm_gpu *gpu) +{ + DBG("%s", gpu->name); + mod_timer(&gpu->inactive_timer, + round_jiffies_up(jiffies + DRM_MSM_INACTIVE_JIFFIES)); +} + +/* * Hangcheck detection for locked gpu: */ @@ -206,7 +273,10 @@ static void recover_worker(struct work_struct *work) dev_err(dev->dev, "%s: hangcheck recover!\n", gpu->name); mutex_lock(&dev->struct_mutex); - gpu->funcs->recover(gpu); + if (msm_gpu_active(gpu)) { + inactive_cancel(gpu); + gpu->funcs->recover(gpu); + } mutex_unlock(&dev->struct_mutex); msm_gpu_retire(gpu); @@ -281,6 +351,9 @@ static void retire_worker(struct work_struct *work) } mutex_unlock(&dev->struct_mutex); + + if (!msm_gpu_active(gpu)) + inactive_start(gpu); } /* call from irq handler to schedule work to retire bo's */ @@ -302,6 +375,8 @@ int msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit, gpu->submitted_fence = submit->fence; + inactive_cancel(gpu); + ret = gpu->funcs->submit(gpu, submit, ctx); priv->lastctx = ctx; @@ -357,11 +432,15 @@ int msm_gpu_init(struct drm_device *drm, struct platform_device *pdev, gpu->dev = drm; gpu->funcs = funcs; gpu->name = name; + gpu->inactive = true; INIT_LIST_HEAD(&gpu->active_list); INIT_WORK(&gpu->retire_work, retire_worker); + INIT_WORK(&gpu->inactive_work, inactive_worker); INIT_WORK(&gpu->recover_work, recover_worker); + setup_timer(&gpu->inactive_timer, inactive_handler, + (unsigned long)gpu); setup_timer(&gpu->hangcheck_timer, hangcheck_handler, (unsigned long)gpu); diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h index 458db8c..fad2700 100644 --- a/drivers/gpu/drm/msm/msm_gpu.h +++ b/drivers/gpu/drm/msm/msm_gpu.h @@ -72,6 +72,10 @@ struct msm_gpu { uint32_t submitted_fence; + /* is gpu powered/active? */ + int active_cnt; + bool inactive; + /* worker for handling active-list retiring: */ struct work_struct retire_work; @@ -91,7 +95,12 @@ struct msm_gpu { uint32_t bsc; #endif - /* Hang Detction: */ + /* Hang and Inactivity Detection: + */ +#define DRM_MSM_INACTIVE_PERIOD 66 /* in ms (roughly four frames) */ +#define DRM_MSM_INACTIVE_JIFFIES msecs_to_jiffies(DRM_MSM_INACTIVE_PERIOD) + struct timer_list inactive_timer; + struct work_struct inactive_work; #define DRM_MSM_HANGCHECK_PERIOD 500 /* in ms */ #define DRM_MSM_HANGCHECK_JIFFIES msecs_to_jiffies(DRM_MSM_HANGCHECK_PERIOD) struct timer_list hangcheck_timer; @@ -99,6 +108,11 @@ struct msm_gpu { struct work_struct recover_work; }; +static inline bool msm_gpu_active(struct msm_gpu *gpu) +{ + return gpu->submitted_fence > gpu->funcs->last_fence(gpu); +} + static inline void gpu_write(struct msm_gpu *gpu, u32 reg, u32 data) { msm_writel(data, gpu->mmio + (reg << 2));
-- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel