From bcdfb5e56dc539506f72e8087c993af1f7ff06eb Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 12 Mar 2017 19:00:59 +0000 Subject: [PATCH] drm/etnaviv: add etnaviv cooling device Each Vivante GPU contains a clock divider which can divide the GPU clock by 2^n, which can lower the power dissipation from the GPU. It has been suggested that the GC600 on Dove is responsible for 20-30% of the power dissipation from the SoC, so lowering the GPU clock rate provides a way to throttle the power dissiptation, and reduce the temperature when the SoC gets hot. This patch hooks the Etnaviv driver into the kernel's thermal management to allow the GPUs to be throttled when necessary, allowing a reduction in GPU clock rate from /1 to /64 in power of 2 steps. Signed-off-by: Russell King Reviewed-by: Lucas Stach Signed-off-by: Lucas Stach --- drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 84 ++++++++++++++++++++++----- drivers/gpu/drm/etnaviv/etnaviv_gpu.h | 2 + 2 files changed, 71 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index a81a2e84f6ad..cab4cf546c17 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -18,6 +18,7 @@ #include #include #include +#include #include "etnaviv_cmdbuf.h" #include "etnaviv_dump.h" @@ -409,6 +410,17 @@ static void etnaviv_gpu_load_clock(struct etnaviv_gpu *gpu, u32 clock) gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, clock); } +static void etnaviv_gpu_update_clock(struct etnaviv_gpu *gpu) +{ + unsigned int fscale = 1 << (6 - gpu->freq_scale); + u32 clock; + + clock = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS | + VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(fscale); + + etnaviv_gpu_load_clock(gpu, clock); +} + static int etnaviv_hw_reset(struct etnaviv_gpu *gpu) { u32 control, idle; @@ -426,11 +438,10 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu) timeout = jiffies + msecs_to_jiffies(1000); while (time_is_after_jiffies(timeout)) { - control = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS | - VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40); - /* enable clock */ - etnaviv_gpu_load_clock(gpu, control); + etnaviv_gpu_update_clock(gpu); + + control = gpu_read(gpu, VIVS_HI_CLOCK_CONTROL); /* Wait for stable clock. Vivante's code waited for 1ms */ usleep_range(1000, 10000); @@ -490,11 +501,7 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu) } /* We rely on the GPU running, so program the clock */ - control = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS | - VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40); - - /* enable clock */ - etnaviv_gpu_load_clock(gpu, control); + etnaviv_gpu_update_clock(gpu); return 0; } @@ -1532,17 +1539,13 @@ static int etnaviv_gpu_hw_suspend(struct etnaviv_gpu *gpu) #ifdef CONFIG_PM static int etnaviv_gpu_hw_resume(struct etnaviv_gpu *gpu) { - u32 clock; int ret; ret = mutex_lock_killable(&gpu->lock); if (ret) return ret; - clock = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS | - VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40); - - etnaviv_gpu_load_clock(gpu, clock); + etnaviv_gpu_update_clock(gpu); etnaviv_gpu_hw_init(gpu); gpu->switch_context = true; @@ -1554,6 +1557,47 @@ static int etnaviv_gpu_hw_resume(struct etnaviv_gpu *gpu) } #endif +static int +etnaviv_gpu_cooling_get_max_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + *state = 6; + + return 0; +} + +static int +etnaviv_gpu_cooling_get_cur_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct etnaviv_gpu *gpu = cdev->devdata; + + *state = gpu->freq_scale; + + return 0; +} + +static int +etnaviv_gpu_cooling_set_cur_state(struct thermal_cooling_device *cdev, + unsigned long state) +{ + struct etnaviv_gpu *gpu = cdev->devdata; + + mutex_lock(&gpu->lock); + gpu->freq_scale = state; + if (!pm_runtime_suspended(gpu->dev)) + etnaviv_gpu_update_clock(gpu); + mutex_unlock(&gpu->lock); + + return 0; +} + +static struct thermal_cooling_device_ops cooling_ops = { + .get_max_state = etnaviv_gpu_cooling_get_max_state, + .get_cur_state = etnaviv_gpu_cooling_get_cur_state, + .set_cur_state = etnaviv_gpu_cooling_set_cur_state, +}; + static int etnaviv_gpu_bind(struct device *dev, struct device *master, void *data) { @@ -1562,13 +1606,20 @@ static int etnaviv_gpu_bind(struct device *dev, struct device *master, struct etnaviv_gpu *gpu = dev_get_drvdata(dev); int ret; + gpu->cooling = thermal_of_cooling_device_register(dev->of_node, + (char *)dev_name(dev), gpu, &cooling_ops); + if (IS_ERR(gpu->cooling)) + return PTR_ERR(gpu->cooling); + #ifdef CONFIG_PM ret = pm_runtime_get_sync(gpu->dev); #else ret = etnaviv_gpu_clk_enable(gpu); #endif - if (ret < 0) + if (ret < 0) { + thermal_cooling_device_unregister(gpu->cooling); return ret; + } gpu->drm = drm; gpu->fence_context = dma_fence_context_alloc(1); @@ -1622,6 +1673,9 @@ static void etnaviv_gpu_unbind(struct device *dev, struct device *master, } gpu->drm = NULL; + + thermal_cooling_device_unregister(gpu->cooling); + gpu->cooling = NULL; } static const struct component_ops gpu_ops = { diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h index 1c0606ea7d5e..6a1e68eec24c 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h @@ -97,6 +97,7 @@ struct etnaviv_cmdbuf; struct etnaviv_gpu { struct drm_device *drm; + struct thermal_cooling_device *cooling; struct device *dev; struct mutex lock; struct etnaviv_chip_identity identity; @@ -150,6 +151,7 @@ struct etnaviv_gpu { u32 hangcheck_fence; u32 hangcheck_dma_addr; struct work_struct recover_work; + unsigned int freq_scale; }; static inline void gpu_write(struct etnaviv_gpu *gpu, u32 reg, u32 data) -- GitLab