[PATCH v2 1/3] drm/msm: Add support for GPU cooling

From: Akhil P Oommen
Date: Mon Oct 19 2020 - 09:14:45 EST


Register GPU as a devfreq cooling device so that it can be passively
cooled by the thermal framework.

Signed-off-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxx>
---
Changes in v2:
1. Update the dt bindings documentation

drivers/gpu/drm/msm/msm_gpu.c | 12 ++++++++++++
drivers/gpu/drm/msm/msm_gpu.h | 2 ++
2 files changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 55d1648..9f9db46 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -14,6 +14,7 @@
#include <generated/utsrelease.h>
#include <linux/string_helpers.h>
#include <linux/devfreq.h>
+#include <linux/devfreq_cooling.h>
#include <linux/devcoredump.h>
#include <linux/sched/task.h>

@@ -107,9 +108,18 @@ static void msm_devfreq_init(struct msm_gpu *gpu)
if (IS_ERR(gpu->devfreq.devfreq)) {
DRM_DEV_ERROR(&gpu->pdev->dev, "Couldn't initialize GPU devfreq\n");
gpu->devfreq.devfreq = NULL;
+ return;
}

devfreq_suspend_device(gpu->devfreq.devfreq);
+
+ gpu->cooling = of_devfreq_cooling_register(gpu->pdev->dev.of_node,
+ gpu->devfreq.devfreq);
+ if (IS_ERR(gpu->cooling)) {
+ DRM_DEV_ERROR(&gpu->pdev->dev,
+ "Couldn't register GPU cooling device\n");
+ gpu->cooling = NULL;
+ }
}

static int enable_pwrrail(struct msm_gpu *gpu)
@@ -1005,4 +1015,6 @@ void msm_gpu_cleanup(struct msm_gpu *gpu)
gpu->aspace->mmu->funcs->detach(gpu->aspace->mmu);
msm_gem_address_space_put(gpu->aspace);
}
+
+ devfreq_cooling_unregister(gpu->cooling);
}
diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h
index 6c9e1fd..9a8f20d 100644
--- a/drivers/gpu/drm/msm/msm_gpu.h
+++ b/drivers/gpu/drm/msm/msm_gpu.h
@@ -147,6 +147,8 @@ struct msm_gpu {
struct msm_gpu_state *crashstate;
/* True if the hardware supports expanded apriv (a650 and newer) */
bool hw_apriv;
+
+ struct thermal_cooling_device *cooling;
};

static inline struct msm_gpu *dev_to_gpu(struct device *dev)
--
2.7.4