[PATCH RFT 5/5] drm/msm: Attach a driver to the GMU

From: Akhil P Oommen

Date: Tue May 12 2026 - 16:53:50 EST


With the introduction of sync_state in the genpd framework, any consumer
device of GCC and GPUCC which is not bound to a driver will result in
bootup warnings like below:

[ 24.362666] gcc-kaanapali 100000.clock-controller: sync_state() pending due to 3d37000.gmu
[ 24.371210] gxclkctl-kaanapali 3d64000.clock-controller: sync_state() pending due to 3d37000.gmu
[ 24.380268] gpucc-kaanapali 3d90000.clock-controller: sync_state() pending due to 3d37000.gmu

To silence these warnings and also to have a proper state in driver core,
attach a driver to the GMU and set it up as a component device for the drm
master device.

Signed-off-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 70 ++++++++++++++++++++++++++++--
drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 30 +++++--------
drivers/gpu/drm/msm/adreno/a6xx_gpu.h | 3 --
drivers/gpu/drm/msm/adreno/adreno_device.c | 2 +
drivers/gpu/drm/msm/adreno/adreno_gpu.h | 3 +-
drivers/gpu/drm/msm/msm_drv.c | 17 ++++----
6 files changed, 92 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
index ec13b27feee7..71bb621b01f3 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
@@ -2063,7 +2063,7 @@ void a6xx_gmu_sysprof_setup(struct msm_gpu *gpu)
pm_runtime_put(&gpu->pdev->dev);
}

-void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
+static void a6xx_gmu_destroy(struct a6xx_gpu *a6xx_gpu)
{
struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
@@ -2143,7 +2143,7 @@ static void __iomem *a6xx_gmu_get_mmio(struct platform_device *pdev, resource_si
return ret;
}

-int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
+static int a6xx_gmu_wrapper_pdev_bind(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
{
struct platform_device *pdev = of_find_device_by_node(node);
struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
@@ -2213,6 +2213,8 @@ int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
goto err_mmio;
}

+ mutex_init(&gmu->lock);
+
gmu->initialized = true;

return 0;
@@ -2230,7 +2232,7 @@ int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
return ret;
}

-int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
+static int a6xx_gmu_pdev_bind(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
{
struct platform_device *pdev = of_find_device_by_node(node);
struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
@@ -2415,6 +2417,7 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
/* Initialize RPMh */
a6xx_gmu_rpmh_init(gmu);

+ mutex_init(&gmu->lock);
gmu->initialized = true;

return 0;
@@ -2444,3 +2447,64 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)

return ret;
}
+
+static int a6xx_gmu_bind(struct device *dev, struct device *master, void *data)
+{
+ int (*bind)(struct a6xx_gpu *gpu, struct device_node *node) = of_device_get_match_data(dev);
+ struct a6xx_gpu *a6xx_gpu = dev_get_drvdata(dev);
+
+ if (WARN_ON(!a6xx_gpu))
+ return -ENODEV;
+
+ return bind(a6xx_gpu, dev->of_node);
+}
+
+static void a6xx_gmu_unbind(struct device *dev, struct device *master, void *data)
+{
+ struct a6xx_gpu *a6xx_gpu = dev_get_drvdata(dev);
+
+ a6xx_gmu_destroy(a6xx_gpu);
+ dev_set_drvdata(dev, NULL);
+}
+
+static const struct component_ops a6xx_gmu_bind_ops = {
+ .bind = a6xx_gmu_bind,
+ .unbind = a6xx_gmu_unbind,
+};
+
+static int a6xx_gmu_probe(struct platform_device *pdev)
+{
+ return component_add(&pdev->dev, &a6xx_gmu_bind_ops);
+}
+
+static void a6xx_gmu_remove(struct platform_device *pdev)
+{
+ component_del(&pdev->dev, &a6xx_gmu_bind_ops);
+}
+
+static const struct of_device_id a6xx_gmu_dt_match[] = {
+ { .compatible = "qcom,adreno-gmu", .data = a6xx_gmu_pdev_bind },
+ { .compatible = "qcom,adreno-rgmu", .data = a6xx_gmu_wrapper_pdev_bind },
+ { .compatible = "qcom,adreno-gmu-wrapper", .data = a6xx_gmu_wrapper_pdev_bind },
+ { }
+};
+MODULE_DEVICE_TABLE(of, a6xx_gmu_dt_match);
+
+static struct platform_driver adreno_gmu_driver = {
+ .probe = a6xx_gmu_probe,
+ .remove = a6xx_gmu_remove,
+ .driver = {
+ .name = "adreno_gmu",
+ .of_match_table = a6xx_gmu_dt_match,
+ },
+};
+
+void __init adreno_gmu_register(void)
+{
+ platform_driver_register(&adreno_gmu_driver);
+}
+
+void __exit adreno_gmu_unregister(void)
+{
+ platform_driver_unregister(&adreno_gmu_driver);
+}
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index d5aba072f44c..b4ae38e1a3d8 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -10,6 +10,7 @@

#include <linux/bitfield.h>
#include <linux/devfreq.h>
+#include <linux/of_platform.h>
#include <linux/pm_domain.h>
#include <linux/soc/qcom/llcc-qcom.h>

@@ -2409,8 +2410,6 @@ static void a6xx_destroy(struct msm_gpu *gpu)

a6xx_llc_slices_destroy(a6xx_gpu);

- a6xx_gmu_remove(a6xx_gpu);
-
adreno_gpu_cleanup(adreno_gpu);

kfree(a6xx_gpu);
@@ -2622,6 +2621,7 @@ static struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
struct adreno_platform_config *config = pdev->dev.platform_data;
const struct adreno_info *info = config->info;
struct device_node *node;
+ struct platform_device *gmu_pdev;
struct a6xx_gpu *a6xx_gpu;
struct adreno_gpu *adreno_gpu;
struct msm_gpu *gpu;
@@ -2637,17 +2637,14 @@ static struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
adreno_gpu = &a6xx_gpu->base;
gpu = &adreno_gpu->base;

- mutex_init(&a6xx_gpu->gmu.lock);
spin_lock_init(&a6xx_gpu->aperture_lock);

adreno_gpu->registers = NULL;

- /* Check if there is a GMU phandle and set it up */
node = of_parse_phandle(pdev->dev.of_node, "qcom,gmu", 0);
- /* FIXME: How do we gracefully handle this? */
- BUG_ON(!node);
-
- adreno_gpu->gmu_is_wrapper = of_device_is_compatible(node, "qcom,adreno-gmu-wrapper");
+ WARN_ON(!node);
+ adreno_gpu->gmu_is_wrapper = of_device_is_compatible(node,
+ "qcom,adreno-gmu-wrapper");

adreno_gpu->base.hw_apriv =
!!(info->quirks & ADRENO_QUIRK_HAS_HW_APRIV);
@@ -2686,16 +2683,6 @@ static struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
if (adreno_is_a618(adreno_gpu) || adreno_is_7c3(adreno_gpu))
priv->gpu_clamp_to_idle = true;

- if (adreno_has_gmu_wrapper(adreno_gpu) || adreno_has_rgmu(adreno_gpu))
- ret = a6xx_gmu_wrapper_init(a6xx_gpu, node);
- else
- ret = a6xx_gmu_init(a6xx_gpu, node);
- of_node_put(node);
- if (ret) {
- a6xx_destroy(&(a6xx_gpu->base.base));
- return ERR_PTR(ret);
- }
-
adreno_gpu->uche_trap_base = 0x1fffffffff000ull;

msm_mmu_set_fault_handler(to_msm_vm(gpu->vm)->mmu, gpu,
@@ -2710,6 +2697,13 @@ static struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
/* Set up the preemption specific bits and pieces for each ringbuffer */
a6xx_preempt_init(gpu);

+ gmu_pdev = of_find_device_by_node(node);
+ of_node_put(node);
+ if (gmu_pdev) {
+ platform_set_drvdata(gmu_pdev, a6xx_gpu);
+ put_device(&gmu_pdev->dev);
+ }
+
return gpu;
}

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
index eb431e5e00b1..fe8d68df9944 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
@@ -268,9 +268,6 @@ bool a6xx_gmu_isidle(struct a6xx_gmu *gmu);
int a6xx_gmu_set_oob(struct a6xx_gmu *gmu, enum a6xx_gmu_oob_state state);
void a6xx_gmu_clear_oob(struct a6xx_gmu *gmu, enum a6xx_gmu_oob_state state);

-int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
-int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
-void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu);
void a6xx_gmu_sysprof_setup(struct msm_gpu *gpu);

void a6xx_preempt_init(struct msm_gpu *gpu);
diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index 67686424f3a1..d70f98e283d5 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -423,6 +423,7 @@ void __init adreno_register(void)
return;

platform_driver_register(&adreno_driver);
+ adreno_gmu_register();
}

void __exit adreno_unregister(void)
@@ -430,5 +431,6 @@ void __exit adreno_unregister(void)
if (skip_gpu)
return;

+ adreno_gmu_unregister();
platform_driver_unregister(&adreno_driver);
}
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
index ec643b84646b..3a05cd98d215 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
@@ -642,7 +642,8 @@ int adreno_gpu_state_get(struct msm_gpu *gpu, struct msm_gpu_state *state);
int adreno_gpu_state_put(struct msm_gpu_state *state);
void adreno_show_object(struct drm_printer *p, void **ptr, int len,
bool *encoded);
-
+void adreno_gmu_register(void);
+void adreno_gmu_unregister(void);
/*
* Common helper function to initialize the default address space for arm-smmu
* attached targets
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index af5aa7ff6179..426255fd0801 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -1021,7 +1021,7 @@ static const struct of_device_id msm_gpu_match[] = {
static int add_gpu_components(struct device *dev,
struct component_match **matchptr)
{
- struct device_node *np;
+ struct device_node *np, *gmu_np;

np = of_find_matching_node(NULL, msm_gpu_match);
if (!np)
@@ -1030,6 +1030,11 @@ static int add_gpu_components(struct device *dev,
if (of_device_is_available(np) && adreno_has_gpu(np))
drm_of_component_match_add(dev, matchptr, component_compare_of, np);

+ gmu_np = of_parse_phandle(np, "qcom,gmu", 0);
+ if (of_device_is_available(gmu_np))
+ drm_of_component_match_add(dev, matchptr, component_compare_of, gmu_np);
+
+ of_node_put(gmu_np);
of_node_put(np);

return 0;
@@ -1131,13 +1136,9 @@ int msm_gpu_probe(struct platform_device *pdev)
if (ret)
return ret;

- /*
- * The GPU pdev acts as both the component master and the sole
- * component (added by adreno_probe()). Future patches add the
- * GMU node as a second component on this same master.
- */
- drm_of_component_match_add(&pdev->dev, &match,
- component_compare_of, pdev->dev.of_node);
+ ret = add_gpu_components(&pdev->dev, &match);
+ if (ret)
+ return ret;

return component_master_add_with_match(&pdev->dev, &msm_gpu_drm_ops,
match);

--
2.51.0