[PATCH 4/7] drm/msm: crank down gpu when inactive
Rob Clark
robdclark at gmail.com
Mon Mar 10 09:47:39 PDT 2014
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.
Signed-off-by: Rob Clark <robdclark at gmail.com>
---
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));
--
1.8.5.3
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