[PATCH v9 0/9] drm/etnaviv: Add pci device driver support

[PATCH v9 0/9] drm/etnaviv: Add pci device driver support

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

There is a Vivante GC1000 (v5037) in LS2K1000 and LS7A1000, this GPU is a
PCI device, and it has 2D and 3D cores in the same core. This series is
trying to add PCI device driver support to etnaviv.

v6:
	* Fix build issue on system without CONFIG_PCI enabled
v7:
	* Add a separate patch for the platform driver rearrangement (Bjorn)
	* Switch to runtime check if the GPU is dma coherent or not (Lucas)
	* Add ETNAVIV_PARAM_GPU_COHERENT to allow userspace to query (Lucas)
	* Remove etnaviv_gpu.no_clk member (Lucas)
	* Various Typos and coding style fixed (Bjorn)

v8:
	* Fix typos and remove unnecessary header included (Bjorn).
	* Add a dedicated function to create the virtual master platform
	  device.
v9:
	* Use PCI_VDEVICE() macro (Bjorn)
	* Add trivial stubs for trivial stubs for the PCI driver (Bjorn)
	* Remove a redundant dev_err() usage (Bjorn)
	* Clean up etnaviv_pdev_probe() also.

Sui Jingfeng (9):
  drm/etnaviv: Add a dedicated function to register an irq handler
  drm/etnaviv: Add a dedicated function to get various clocks
  drm/etnaviv: Add dedicated functions to create and destroy platform
    device
  drm/etnaviv: Add helpers for private data construction and destruction
  drm/etnaviv: Allow bypass component framework
  drm/etnaviv: Add driver support for the PCI devices
  drm/etnaviv: Add support for the dma coherent device
  drm/etnaviv: Add a dedicated function to create the virtual master
  drm/etnaviv: Clean up etnaviv_pdev_probe() function

 drivers/gpu/drm/etnaviv/Kconfig             |  10 +
 drivers/gpu/drm/etnaviv/Makefile            |   2 +
 drivers/gpu/drm/etnaviv/etnaviv_drv.c       | 315 ++++++++++++++------
 drivers/gpu/drm/etnaviv/etnaviv_drv.h       |  10 +
 drivers/gpu/drm/etnaviv/etnaviv_gem.c       |  22 +-
 drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c |   7 +-
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c       | 166 +++++++----
 drivers/gpu/drm/etnaviv/etnaviv_gpu.h       |   9 +
 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c   |  75 +++++
 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h   |  18 ++
 include/uapi/drm/etnaviv_drm.h              |   1 +
 11 files changed, 476 insertions(+), 159 deletions(-)
 create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c
 create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h

-- 
2.25.1

[PATCH v9 1/9] drm/etnaviv: Add a dedicated function to register an irq handler

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Because getting IRQ from a device is platform-dependent, PCI devices have
different methods for getting an IRQ. This patch is a preparation patch to
extend the driver for the PCI device support.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 32 +++++++++++++++++++--------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index de8c9894967c..a03e81337d8f 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1817,6 +1817,27 @@ static const struct of_device_id etnaviv_gpu_match[] = {
 };
 MODULE_DEVICE_TABLE(of, etnaviv_gpu_match);
 
+static int etnaviv_gpu_register_irq(struct etnaviv_gpu *gpu, int irq)
+{
+	struct device *dev = gpu->dev;
+	int err;
+
+	if (irq < 0)
+		return irq;
+
+	err = devm_request_irq(dev, irq, irq_handler, 0, dev_name(dev), gpu);
+	if (err) {
+		dev_err(dev, "failed to request irq %u: %d\n", irq, err);
+		return err;
+	}
+
+	gpu->irq = irq;
+
+	dev_info(dev, "irq(%d) handler registered\n", irq);
+
+	return 0;
+}
+
 static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -1837,16 +1858,9 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 		return PTR_ERR(gpu->mmio);
 
 	/* Get Interrupt: */
-	gpu->irq = platform_get_irq(pdev, 0);
-	if (gpu->irq < 0)
-		return gpu->irq;
-
-	err = devm_request_irq(&pdev->dev, gpu->irq, irq_handler, 0,
-			       dev_name(gpu->dev), gpu);
-	if (err) {
-		dev_err(dev, "failed to request IRQ%u: %d\n", gpu->irq, err);
+	err = etnaviv_gpu_register_irq(gpu, platform_get_irq(pdev, 0));
+	if (err)
 		return err;
-	}
 
 	/* Get Clocks: */
 	gpu->clk_reg = devm_clk_get_optional(&pdev->dev, "reg");
-- 
2.25.1

[PATCH v9 2/9] drm/etnaviv: Add a dedicated function to get various clocks

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Because it is also platform-dependent, there are environments where don't
have CLK subsystem support, for example, discreted PCI GPUs. So don't rage
quit if there is no CLK subsystem support.

For the GPU in LS7A1000 and LS2K1000, the working frequency of the GPU is
tuned by configuring the PLL registers.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 53 ++++++++++++++++-----------
 1 file changed, 32 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index a03e81337d8f..5e88fa95dac2 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1565,6 +1565,35 @@ static irqreturn_t irq_handler(int irq, void *data)
 	return ret;
 }
 
+static int etnaviv_gpu_clk_get(struct etnaviv_gpu *gpu)
+{
+	struct device *dev = gpu->dev;
+
+	gpu->clk_reg = devm_clk_get_optional(dev, "reg");
+	DBG("clk_reg: %p", gpu->clk_reg);
+	if (IS_ERR(gpu->clk_reg))
+		return PTR_ERR(gpu->clk_reg);
+
+	gpu->clk_bus = devm_clk_get_optional(dev, "bus");
+	DBG("clk_bus: %p", gpu->clk_bus);
+	if (IS_ERR(gpu->clk_bus))
+		return PTR_ERR(gpu->clk_bus);
+
+	gpu->clk_core = devm_clk_get(dev, "core");
+	DBG("clk_core: %p", gpu->clk_core);
+	if (IS_ERR(gpu->clk_core))
+		return PTR_ERR(gpu->clk_core);
+	gpu->base_rate_core = clk_get_rate(gpu->clk_core);
+
+	gpu->clk_shader = devm_clk_get_optional(dev, "shader");
+	DBG("clk_shader: %p", gpu->clk_shader);
+	if (IS_ERR(gpu->clk_shader))
+		return PTR_ERR(gpu->clk_shader);
+	gpu->base_rate_shader = clk_get_rate(gpu->clk_shader);
+
+	return 0;
+}
+
 static int etnaviv_gpu_clk_enable(struct etnaviv_gpu *gpu)
 {
 	int ret;
@@ -1863,27 +1892,9 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 		return err;
 
 	/* Get Clocks: */
-	gpu->clk_reg = devm_clk_get_optional(&pdev->dev, "reg");
-	DBG("clk_reg: %p", gpu->clk_reg);
-	if (IS_ERR(gpu->clk_reg))
-		return PTR_ERR(gpu->clk_reg);
-
-	gpu->clk_bus = devm_clk_get_optional(&pdev->dev, "bus");
-	DBG("clk_bus: %p", gpu->clk_bus);
-	if (IS_ERR(gpu->clk_bus))
-		return PTR_ERR(gpu->clk_bus);
-
-	gpu->clk_core = devm_clk_get(&pdev->dev, "core");
-	DBG("clk_core: %p", gpu->clk_core);
-	if (IS_ERR(gpu->clk_core))
-		return PTR_ERR(gpu->clk_core);
-	gpu->base_rate_core = clk_get_rate(gpu->clk_core);
-
-	gpu->clk_shader = devm_clk_get_optional(&pdev->dev, "shader");
-	DBG("clk_shader: %p", gpu->clk_shader);
-	if (IS_ERR(gpu->clk_shader))
-		return PTR_ERR(gpu->clk_shader);
-	gpu->base_rate_shader = clk_get_rate(gpu->clk_shader);
+	err = etnaviv_gpu_clk_get(gpu);
+	if (err)
+		return err;
 
 	/* TODO: figure out max mapped size */
 	dev_set_drvdata(dev, gpu);
-- 
2.25.1

[PATCH v9 3/9] drm/etnaviv: Add dedicated functions to create and destroy platform device

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Also rename the virtual master platform device as etnaviv_platform_device,
for better reflection that it is a platform device, not a DRM device.

Another benefit is that we no longer need to call of_node_put() for three
different cases, Instead, we only need to call it once.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 56 +++++++++++++++++++--------
 1 file changed, 39 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 31a7f59ccb49..cec005035d0e 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -656,12 +656,44 @@ static struct platform_driver etnaviv_platform_driver = {
 	},
 };
 
-static struct platform_device *etnaviv_drm;
+static struct platform_device *etnaviv_platform_device;
 
-static int __init etnaviv_init(void)
+static int etnaviv_create_platform_device(const char *name,
+					  struct platform_device **ppdev)
 {
 	struct platform_device *pdev;
 	int ret;
+
+	pdev = platform_device_alloc(name, PLATFORM_DEVID_NONE);
+	if (!pdev)
+		return -ENOMEM;
+
+	ret = platform_device_add(pdev);
+	if (ret) {
+		platform_device_put(pdev);
+		return ret;
+	}
+
+	*ppdev = pdev;
+
+	return 0;
+}
+
+static void etnaviv_destroy_platform_device(struct platform_device **ppdev)
+{
+	struct platform_device *pdev = *ppdev;
+
+	if (!pdev)
+		return;
+
+	platform_device_unregister(pdev);
+
+	*ppdev = NULL;
+}
+
+static int __init etnaviv_init(void)
+{
+	int ret;
 	struct device_node *np;
 
 	etnaviv_validate_init();
@@ -681,23 +713,13 @@ static int __init etnaviv_init(void)
 	for_each_compatible_node(np, NULL, "vivante,gc") {
 		if (!of_device_is_available(np))
 			continue;
+		of_node_put(np);
 
-		pdev = platform_device_alloc("etnaviv", PLATFORM_DEVID_NONE);
-		if (!pdev) {
-			ret = -ENOMEM;
-			of_node_put(np);
-			goto unregister_platform_driver;
-		}
-
-		ret = platform_device_add(pdev);
-		if (ret) {
-			platform_device_put(pdev);
-			of_node_put(np);
+		ret = etnaviv_create_platform_device("etnaviv",
+						     &etnaviv_platform_device);
+		if (ret)
 			goto unregister_platform_driver;
-		}
 
-		etnaviv_drm = pdev;
-		of_node_put(np);
 		break;
 	}
 
@@ -713,7 +735,7 @@ module_init(etnaviv_init);
 
 static void __exit etnaviv_exit(void)
 {
-	platform_device_unregister(etnaviv_drm);
+	etnaviv_destroy_platform_device(&etnaviv_platform_device);
 	platform_driver_unregister(&etnaviv_platform_driver);
 	platform_driver_unregister(&etnaviv_gpu_driver);
 }
-- 
2.25.1

[PATCH v9 4/9] drm/etnaviv: Add helpers for private data construction and destruction

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

struct etnaviv_drm_private contains a lot of common resources that are
shared by all GPUs. This patch introduces two dedicated functions, which
is for the construction and destruction of instances of this structure.
    
The idea is to avoid leaking its members outside. The error handling code
can also be simplified.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 73 +++++++++++++++++----------
 drivers/gpu/drm/etnaviv/etnaviv_drv.h |  1 +
 2 files changed, 47 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index cec005035d0e..6a048be02857 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -24,9 +24,47 @@
 #include "etnaviv_perfmon.h"
 
 /*
- * DRM operations:
+ * etnaviv private data construction and destructions:
  */
+static struct etnaviv_drm_private *
+etnaviv_alloc_private(struct device *dev, struct drm_device *drm)
+{
+	struct etnaviv_drm_private *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return ERR_PTR(-ENOMEM);
+
+	priv->drm = drm;
+
+	xa_init_flags(&priv->active_contexts, XA_FLAGS_ALLOC);
+
+	mutex_init(&priv->gem_lock);
+	INIT_LIST_HEAD(&priv->gem_list);
+	priv->num_gpus = 0;
+	priv->shm_gfp_mask = GFP_HIGHUSER | __GFP_RETRY_MAYFAIL | __GFP_NOWARN;
 
+	priv->cmdbuf_suballoc = etnaviv_cmdbuf_suballoc_new(dev);
+	if (IS_ERR(priv->cmdbuf_suballoc)) {
+		kfree(priv);
+		dev_err(dev, "Failed to create cmdbuf suballocator\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return priv;
+}
+
+static void etnaviv_free_private(struct etnaviv_drm_private *priv)
+{
+	if (!priv)
+		return;
+
+	etnaviv_cmdbuf_suballoc_destroy(priv->cmdbuf_suballoc);
+
+	xa_destroy(&priv->active_contexts);
+
+	kfree(priv);
+}
 
 static void load_gpu(struct drm_device *dev)
 {
@@ -511,35 +549,21 @@ static int etnaviv_bind(struct device *dev)
 	if (IS_ERR(drm))
 		return PTR_ERR(drm);
 
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (!priv) {
-		dev_err(dev, "failed to allocate private data\n");
-		ret = -ENOMEM;
+	priv = etnaviv_alloc_private(dev, drm);
+	if (IS_ERR(priv)) {
+		ret = PTR_ERR(priv);
 		goto out_put;
 	}
+
 	drm->dev_private = priv;
 
 	dma_set_max_seg_size(dev, SZ_2G);
 
-	xa_init_flags(&priv->active_contexts, XA_FLAGS_ALLOC);
-
-	mutex_init(&priv->gem_lock);
-	INIT_LIST_HEAD(&priv->gem_list);
-	priv->num_gpus = 0;
-	priv->shm_gfp_mask = GFP_HIGHUSER | __GFP_RETRY_MAYFAIL | __GFP_NOWARN;
-
-	priv->cmdbuf_suballoc = etnaviv_cmdbuf_suballoc_new(drm->dev);
-	if (IS_ERR(priv->cmdbuf_suballoc)) {
-		dev_err(drm->dev, "Failed to create cmdbuf suballocator\n");
-		ret = PTR_ERR(priv->cmdbuf_suballoc);
-		goto out_free_priv;
-	}
-
 	dev_set_drvdata(dev, drm);
 
 	ret = component_bind_all(dev, drm);
 	if (ret < 0)
-		goto out_destroy_suballoc;
+		goto out_free_priv;
 
 	load_gpu(drm);
 
@@ -551,10 +575,8 @@ static int etnaviv_bind(struct device *dev)
 
 out_unbind:
 	component_unbind_all(dev, drm);
-out_destroy_suballoc:
-	etnaviv_cmdbuf_suballoc_destroy(priv->cmdbuf_suballoc);
 out_free_priv:
-	kfree(priv);
+	etnaviv_free_private(priv);
 out_put:
 	drm_dev_put(drm);
 
@@ -570,12 +592,9 @@ static void etnaviv_unbind(struct device *dev)
 
 	component_unbind_all(dev, drm);
 
-	etnaviv_cmdbuf_suballoc_destroy(priv->cmdbuf_suballoc);
-
-	xa_destroy(&priv->active_contexts);
+	etnaviv_free_private(priv);
 
 	drm->dev_private = NULL;
-	kfree(priv);
 
 	drm_dev_put(drm);
 }
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
index b3eb1662e90c..e58f82e698de 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
@@ -35,6 +35,7 @@ struct etnaviv_file_private {
 };
 
 struct etnaviv_drm_private {
+	struct drm_device *drm;
 	int num_gpus;
 	struct etnaviv_gpu *gpu[ETNA_MAX_PIPES];
 	gfp_t shm_gfp_mask;
-- 
2.25.1

[PATCH v9 5/9] drm/etnaviv: Allow bypass component framework

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Adding additional code path to allow bypass component frameworks, A
platform with a single GPU core could probably try the non-component
code path. This patch is for code sharing, no functional change.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 47 ++++++++++-----
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 83 +++++++++++++++++----------
 drivers/gpu/drm/etnaviv/etnaviv_gpu.h |  3 +
 3 files changed, 91 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 6a048be02857..93ca240cd4c0 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -536,10 +536,9 @@ static const struct drm_driver etnaviv_drm_driver = {
 	.minor              = 3,
 };
 
-/*
- * Platform driver:
- */
-static int etnaviv_bind(struct device *dev)
+static struct etnaviv_drm_private *etna_private_ptr;
+
+static int etnaviv_drm_bind(struct device *dev, bool component)
 {
 	struct etnaviv_drm_private *priv;
 	struct drm_device *drm;
@@ -556,12 +555,15 @@ static int etnaviv_bind(struct device *dev)
 	}
 
 	drm->dev_private = priv;
+	etna_private_ptr = priv;
 
 	dma_set_max_seg_size(dev, SZ_2G);
 
-	dev_set_drvdata(dev, drm);
+	if (component)
+		ret = component_bind_all(dev, drm);
+	else
+		ret = etnaviv_gpu_bind(dev, NULL, drm);
 
-	ret = component_bind_all(dev, drm);
 	if (ret < 0)
 		goto out_free_priv;
 
@@ -574,7 +576,10 @@ static int etnaviv_bind(struct device *dev)
 	return 0;
 
 out_unbind:
-	component_unbind_all(dev, drm);
+	if (component)
+		component_unbind_all(dev, drm);
+	else
+		etnaviv_gpu_unbind(dev, NULL, drm);
 out_free_priv:
 	etnaviv_free_private(priv);
 out_put:
@@ -583,14 +588,17 @@ static int etnaviv_bind(struct device *dev)
 	return ret;
 }
 
-static void etnaviv_unbind(struct device *dev)
+static void etnaviv_drm_unbind(struct device *dev, bool component)
 {
-	struct drm_device *drm = dev_get_drvdata(dev);
-	struct etnaviv_drm_private *priv = drm->dev_private;
+	struct etnaviv_drm_private *priv = etna_private_ptr;
+	struct drm_device *drm = priv->drm;
 
 	drm_dev_unregister(drm);
 
-	component_unbind_all(dev, drm);
+	if (component)
+		component_unbind_all(dev, drm);
+	else
+		etnaviv_gpu_unbind(dev, NULL, drm);
 
 	etnaviv_free_private(priv);
 
@@ -599,9 +607,22 @@ static void etnaviv_unbind(struct device *dev)
 	drm_dev_put(drm);
 }
 
+/*
+ * Platform driver:
+ */
+static int etnaviv_master_bind(struct device *dev)
+{
+	return etnaviv_drm_bind(dev, true);
+}
+
+static void etnaviv_master_unbind(struct device *dev)
+{
+	return etnaviv_drm_unbind(dev, true);
+}
+
 static const struct component_master_ops etnaviv_master_ops = {
-	.bind = etnaviv_bind,
-	.unbind = etnaviv_unbind,
+	.bind = etnaviv_master_bind,
+	.unbind = etnaviv_master_unbind,
 };
 
 static int etnaviv_pdev_probe(struct platform_device *pdev)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index 5e88fa95dac2..059be8c89c5a 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1737,8 +1737,7 @@ static const struct thermal_cooling_device_ops cooling_ops = {
 	.set_cur_state = etnaviv_gpu_cooling_set_cur_state,
 };
 
-static int etnaviv_gpu_bind(struct device *dev, struct device *master,
-	void *data)
+int etnaviv_gpu_bind(struct device *dev, struct device *master, void *data)
 {
 	struct drm_device *drm = data;
 	struct etnaviv_drm_private *priv = drm->dev_private;
@@ -1769,7 +1768,6 @@ static int etnaviv_gpu_bind(struct device *dev, struct device *master,
 	if (ret < 0)
 		goto out_sched;
 
-
 	gpu->drm = drm;
 	gpu->fence_context = dma_fence_context_alloc(1);
 	xa_init_flags(&gpu->user_fences, XA_FLAGS_ALLOC);
@@ -1798,8 +1796,7 @@ static int etnaviv_gpu_bind(struct device *dev, struct device *master,
 	return ret;
 }
 
-static void etnaviv_gpu_unbind(struct device *dev, struct device *master,
-	void *data)
+void etnaviv_gpu_unbind(struct device *dev, struct device *master, void *data)
 {
 	struct etnaviv_gpu *gpu = dev_get_drvdata(dev);
 
@@ -1867,9 +1864,11 @@ static int etnaviv_gpu_register_irq(struct etnaviv_gpu *gpu, int irq)
 	return 0;
 }
 
-static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
+/* platform independent */
+
+static int etnaviv_gpu_driver_create(struct device *dev, void __iomem *mmio,
+				     int irq, bool component, bool has_clk)
 {
-	struct device *dev = &pdev->dev;
 	struct etnaviv_gpu *gpu;
 	int err;
 
@@ -1877,24 +1876,22 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 	if (!gpu)
 		return -ENOMEM;
 
-	gpu->dev = &pdev->dev;
+	gpu->dev = dev;
+	gpu->mmio = mmio;
 	mutex_init(&gpu->lock);
 	mutex_init(&gpu->sched_lock);
 
-	/* Map registers: */
-	gpu->mmio = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(gpu->mmio))
-		return PTR_ERR(gpu->mmio);
-
 	/* Get Interrupt: */
-	err = etnaviv_gpu_register_irq(gpu, platform_get_irq(pdev, 0));
+	err = etnaviv_gpu_register_irq(gpu, irq);
 	if (err)
 		return err;
 
 	/* Get Clocks: */
-	err = etnaviv_gpu_clk_get(gpu);
-	if (err)
-		return err;
+	if (has_clk) {
+		err = etnaviv_gpu_clk_get(gpu);
+		if (err)
+			return err;
+	}
 
 	/* TODO: figure out max mapped size */
 	dev_set_drvdata(dev, gpu);
@@ -1904,24 +1901,27 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
 	 * autosuspend delay is rather arbitary: no measurements have
 	 * yet been performed to determine an appropriate value.
 	 */
-	pm_runtime_use_autosuspend(gpu->dev);
-	pm_runtime_set_autosuspend_delay(gpu->dev, 200);
-	pm_runtime_enable(gpu->dev);
-
-	err = component_add(&pdev->dev, &gpu_ops);
-	if (err < 0) {
-		dev_err(&pdev->dev, "failed to register component: %d\n", err);
-		return err;
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_set_autosuspend_delay(dev, 200);
+	pm_runtime_enable(dev);
+
+	if (component) {
+		err = component_add(dev, &gpu_ops);
+		if (err < 0) {
+			dev_err(dev, "failed to register component: %d\n", err);
+			return err;
+		}
 	}
 
 	return 0;
 }
 
-static int etnaviv_gpu_platform_remove(struct platform_device *pdev)
+static void etnaviv_gpu_driver_destroy(struct device *dev, bool component)
 {
-	component_del(&pdev->dev, &gpu_ops);
-	pm_runtime_disable(&pdev->dev);
-	return 0;
+	if (component)
+		component_del(dev, &gpu_ops);
+
+	pm_runtime_disable(dev);
 }
 
 static int etnaviv_gpu_rpm_suspend(struct device *dev)
@@ -1971,6 +1971,31 @@ static const struct dev_pm_ops etnaviv_gpu_pm_ops = {
 	RUNTIME_PM_OPS(etnaviv_gpu_rpm_suspend, etnaviv_gpu_rpm_resume, NULL)
 };
 
+static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	void __iomem *mmio;
+	int irq;
+
+	/* Map registers: */
+	mmio = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(mmio))
+		return PTR_ERR(mmio);
+
+	irq = platform_get_irq(pdev, 0);
+
+	return etnaviv_gpu_driver_create(dev, mmio, irq, true, true);
+}
+
+static int etnaviv_gpu_platform_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	etnaviv_gpu_driver_destroy(dev, true);
+
+	return 0;
+}
+
 struct platform_driver etnaviv_gpu_driver = {
 	.driver = {
 		.name = "etnaviv-gpu",
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
index 98c6f9c320fc..1ec829a649b5 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
@@ -206,6 +206,9 @@ void etnaviv_gpu_pm_put(struct etnaviv_gpu *gpu);
 int etnaviv_gpu_wait_idle(struct etnaviv_gpu *gpu, unsigned int timeout_ms);
 void etnaviv_gpu_start_fe(struct etnaviv_gpu *gpu, u32 address, u16 prefetch);
 
+int etnaviv_gpu_bind(struct device *dev, struct device *master, void *data);
+void etnaviv_gpu_unbind(struct device *dev, struct device *master, void *data);
+
 extern struct platform_driver etnaviv_gpu_driver;
 
 #endif /* __ETNAVIV_GPU_H__ */
-- 
2.25.1

[PATCH v9 6/9] drm/etnaviv: Add driver support for the PCI devices

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

This patch adds PCI driver support on top of what we already have. Take
the GC1000 in LS7A1000/LS2K1000 as the first instance of the PCI device
driver. There is only one GPU core for the GC1000 in the LS7A1000 and
LS2K1000. Therefore, component frameworks can be avoided.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/Kconfig           | 10 +++
 drivers/gpu/drm/etnaviv/Makefile          |  2 +
 drivers/gpu/drm/etnaviv/etnaviv_drv.c     | 13 +++-
 drivers/gpu/drm/etnaviv/etnaviv_drv.h     |  3 +
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c     |  8 +--
 drivers/gpu/drm/etnaviv/etnaviv_gpu.h     |  6 ++
 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c | 75 +++++++++++++++++++++++
 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h | 18 ++++++
 8 files changed, 128 insertions(+), 7 deletions(-)
 create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c
 create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h

diff --git a/drivers/gpu/drm/etnaviv/Kconfig b/drivers/gpu/drm/etnaviv/Kconfig
index faa7fc68b009..1b5b162efb61 100644
--- a/drivers/gpu/drm/etnaviv/Kconfig
+++ b/drivers/gpu/drm/etnaviv/Kconfig
@@ -15,6 +15,16 @@ config DRM_ETNAVIV
 	help
 	  DRM driver for Vivante GPUs.
 
+config DRM_ETNAVIV_PCI_DRIVER
+	bool "enable ETNAVIV PCI driver support"
+	depends on DRM_ETNAVIV
+	depends on PCI
+	default y
+	help
+	  Compile in support for PCI GPUs of Vivante.
+	  For example, the GC1000 in LS7A1000 and LS2K1000.
+	  Say Y if you have such a hardware.
+
 config DRM_ETNAVIV_THERMAL
 	bool "enable ETNAVIV thermal throttling"
 	depends on DRM_ETNAVIV
diff --git a/drivers/gpu/drm/etnaviv/Makefile b/drivers/gpu/drm/etnaviv/Makefile
index 46e5ffad69a6..6829e1ebf2db 100644
--- a/drivers/gpu/drm/etnaviv/Makefile
+++ b/drivers/gpu/drm/etnaviv/Makefile
@@ -16,4 +16,6 @@ etnaviv-y := \
 	etnaviv_perfmon.o \
 	etnaviv_sched.o
 
+etnaviv-$(CONFIG_DRM_ETNAVIV_PCI_DRIVER) += etnaviv_pci_drv.o
+
 obj-$(CONFIG_DRM_ETNAVIV)	+= etnaviv.o
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 93ca240cd4c0..0a365e96d371 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -21,6 +21,7 @@
 #include "etnaviv_gpu.h"
 #include "etnaviv_gem.h"
 #include "etnaviv_mmu.h"
+#include "etnaviv_pci_drv.h"
 #include "etnaviv_perfmon.h"
 
 /*
@@ -538,7 +539,7 @@ static const struct drm_driver etnaviv_drm_driver = {
 
 static struct etnaviv_drm_private *etna_private_ptr;
 
-static int etnaviv_drm_bind(struct device *dev, bool component)
+int etnaviv_drm_bind(struct device *dev, bool component)
 {
 	struct etnaviv_drm_private *priv;
 	struct drm_device *drm;
@@ -588,7 +589,7 @@ static int etnaviv_drm_bind(struct device *dev, bool component)
 	return ret;
 }
 
-static void etnaviv_drm_unbind(struct device *dev, bool component)
+void etnaviv_drm_unbind(struct device *dev, bool component)
 {
 	struct etnaviv_drm_private *priv = etna_private_ptr;
 	struct drm_device *drm = priv->drm;
@@ -746,6 +747,10 @@ static int __init etnaviv_init(void)
 	if (ret != 0)
 		goto unregister_gpu_driver;
 
+	ret = etnaviv_register_pci_driver();
+	if (ret != 0)
+		goto unregister_platform_driver;
+
 	/*
 	 * If the DT contains at least one available GPU device, instantiate
 	 * the DRM platform device.
@@ -763,7 +768,7 @@ static int __init etnaviv_init(void)
 		break;
 	}
 
-	return 0;
+	return ret;
 
 unregister_platform_driver:
 	platform_driver_unregister(&etnaviv_platform_driver);
@@ -778,6 +783,8 @@ static void __exit etnaviv_exit(void)
 	etnaviv_destroy_platform_device(&etnaviv_platform_device);
 	platform_driver_unregister(&etnaviv_platform_driver);
 	platform_driver_unregister(&etnaviv_gpu_driver);
+
+	etnaviv_unregister_pci_driver();
 }
 module_exit(etnaviv_exit);
 
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
index e58f82e698de..9cd72948cfad 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
@@ -83,6 +83,9 @@ bool etnaviv_cmd_validate_one(struct etnaviv_gpu *gpu,
 	u32 *stream, unsigned int size,
 	struct drm_etnaviv_gem_submit_reloc *relocs, unsigned int reloc_size);
 
+int etnaviv_drm_bind(struct device *dev, bool component);
+void etnaviv_drm_unbind(struct device *dev, bool component);
+
 #ifdef CONFIG_DEBUG_FS
 void etnaviv_gem_describe_objects(struct etnaviv_drm_private *priv,
 	struct seq_file *m);
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index 059be8c89c5a..d6a21e97feb1 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1866,8 +1866,8 @@ static int etnaviv_gpu_register_irq(struct etnaviv_gpu *gpu, int irq)
 
 /* platform independent */
 
-static int etnaviv_gpu_driver_create(struct device *dev, void __iomem *mmio,
-				     int irq, bool component, bool has_clk)
+int etnaviv_gpu_driver_create(struct device *dev, void __iomem *mmio,
+			      int irq, bool component, bool has_clk)
 {
 	struct etnaviv_gpu *gpu;
 	int err;
@@ -1916,7 +1916,7 @@ static int etnaviv_gpu_driver_create(struct device *dev, void __iomem *mmio,
 	return 0;
 }
 
-static void etnaviv_gpu_driver_destroy(struct device *dev, bool component)
+void etnaviv_gpu_driver_destroy(struct device *dev, bool component)
 {
 	if (component)
 		component_del(dev, &gpu_ops);
@@ -1967,7 +1967,7 @@ static int etnaviv_gpu_rpm_resume(struct device *dev)
 	return 0;
 }
 
-static const struct dev_pm_ops etnaviv_gpu_pm_ops = {
+const struct dev_pm_ops etnaviv_gpu_pm_ops = {
 	RUNTIME_PM_OPS(etnaviv_gpu_rpm_suspend, etnaviv_gpu_rpm_resume, NULL)
 };
 
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
index 1ec829a649b5..8d9833996ed7 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
@@ -209,6 +209,12 @@ void etnaviv_gpu_start_fe(struct etnaviv_gpu *gpu, u32 address, u16 prefetch);
 int etnaviv_gpu_bind(struct device *dev, struct device *master, void *data);
 void etnaviv_gpu_unbind(struct device *dev, struct device *master, void *data);
 
+int etnaviv_gpu_driver_create(struct device *dev, void __iomem *mmio,
+			      int irq, bool component, bool has_clk);
+
+void etnaviv_gpu_driver_destroy(struct device *dev, bool component);
+
 extern struct platform_driver etnaviv_gpu_driver;
+extern const struct dev_pm_ops etnaviv_gpu_pm_ops;
 
 #endif /* __ETNAVIV_GPU_H__ */
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c
new file mode 100644
index 000000000000..78e44a28d30c
--- /dev/null
+++ b/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/pci.h>
+
+#include "etnaviv_drv.h"
+#include "etnaviv_gpu.h"
+#include "etnaviv_pci_drv.h"
+
+static int etnaviv_pci_probe(struct pci_dev *pdev,
+			     const struct pci_device_id *ent)
+{
+	struct device *dev = &pdev->dev;
+	void __iomem *mmio;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret) {
+		dev_err(dev, "failed to enable\n");
+		return ret;
+	}
+
+	pci_set_master(pdev);
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	/* Map registers, assume the PCI bar 0 contain the registers */
+	mmio = pcim_iomap(pdev, 0, 0);
+	if (IS_ERR(mmio))
+		return PTR_ERR(mmio);
+
+	ret = etnaviv_gpu_driver_create(dev, mmio, pdev->irq, false, false);
+	if (ret)
+		return ret;
+
+	return etnaviv_drm_bind(dev, false);
+}
+
+static void etnaviv_pci_remove(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	etnaviv_drm_unbind(dev, false);
+
+	etnaviv_gpu_driver_destroy(dev, false);
+
+	pci_clear_master(pdev);
+}
+
+static const struct pci_device_id etnaviv_pci_id_lists[] = {
+	{PCI_VDEVICE(LOONGSON, 0x7a15)},
+	{PCI_VDEVICE(LOONGSON, 0x7a05)},
+	{ }
+};
+
+static struct pci_driver etnaviv_pci_driver = {
+	.name = "etnaviv",
+	.id_table = etnaviv_pci_id_lists,
+	.probe = etnaviv_pci_probe,
+	.remove = etnaviv_pci_remove,
+	.driver.pm = pm_ptr(&etnaviv_gpu_pm_ops),
+};
+
+int etnaviv_register_pci_driver(void)
+{
+	return pci_register_driver(&etnaviv_pci_driver);
+}
+
+void etnaviv_unregister_pci_driver(void)
+{
+	pci_unregister_driver(&etnaviv_pci_driver);
+}
+
+MODULE_DEVICE_TABLE(pci, etnaviv_pci_id_lists);
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h
new file mode 100644
index 000000000000..46dffa27f8c5
--- /dev/null
+++ b/drivers/gpu/drm/etnaviv/etnaviv_pci_drv.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ETNAVIV_PCI_DRV_H__
+#define __ETNAVIV_PCI_DRV_H__
+
+#ifdef CONFIG_DRM_ETNAVIV_PCI_DRIVER
+
+int etnaviv_register_pci_driver(void);
+void etnaviv_unregister_pci_driver(void);
+
+#else
+
+int etnaviv_register_pci_driver(void) { return 0; }
+void etnaviv_unregister_pci_driver(void) { }
+
+#endif
+
+#endif
-- 
2.25.1

[PATCH v9 7/9] drm/etnaviv: Add support for the dma coherent device

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Loongson CPUs maintain cache coherency by hardware, which means that the
data in the CPU cache is identical to the data in main system memory. As
for the peripheral device, most of Loongson chips chose to define the
peripherals as DMA coherent by default, device drivers do not need to
maintain the coherency between a processor and an I/O device manually.

There are exceptions, for LS2K1000 SoC, part of peripheral device can be
configured as DMA non-coherent. But there is no released version of such
firmware exist in the market. Peripherals of older LS2K1000 is also DMA
non-coherent, but they are nearly outdated. So, those are trivial cases.

Nevertheless, kernel space still need to do the probe work, because vivante
GPU IP has been integrated into various platform. Hence, this patch add
runtime detection code to probe if a specific GPU is DMA coherent, If the
answer is yes, we are going to utilize such features. On Loongson platform,
When a buffer is accessed by both the GPU and the CPU, the driver should
prefer ETNA_BO_CACHED over ETNA_BO_WC.

This patch also add a new parameter: etnaviv_param_gpu_coherent, which
allow userspace to know if such a feature is available. Because
write-combined BO is still preferred in some case, especially where don't
need CPU read, for example, uploading shader bin.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c       | 34 +++++++++++++++++++++
 drivers/gpu/drm/etnaviv/etnaviv_drv.h       |  6 ++++
 drivers/gpu/drm/etnaviv/etnaviv_gem.c       | 22 ++++++++++---
 drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c |  7 ++++-
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c       |  4 +++
 include/uapi/drm/etnaviv_drm.h              |  1 +
 6 files changed, 69 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 0a365e96d371..1c9386e5a1b0 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -5,7 +5,9 @@
 
 #include <linux/component.h>
 #include <linux/dma-mapping.h>
+#include <linux/dma-map-ops.h>
 #include <linux/module.h>
+#include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/uaccess.h>
 
@@ -24,6 +26,34 @@
 #include "etnaviv_pci_drv.h"
 #include "etnaviv_perfmon.h"
 
+static struct device_node *etnaviv_of_first_available_node(void)
+{
+	struct device_node *core_node;
+
+	for_each_compatible_node(core_node, NULL, "vivante,gc") {
+		if (of_device_is_available(core_node))
+			return core_node;
+	}
+
+	return NULL;
+}
+
+static bool etnaviv_is_dma_coherent(struct device *dev)
+{
+	struct device_node *np;
+	bool coherent;
+
+	np = etnaviv_of_first_available_node();
+	if (np) {
+		coherent = of_dma_is_coherent(np);
+		of_node_put(np);
+	} else {
+		coherent = dev_is_dma_coherent(dev);
+	}
+
+	return coherent;
+}
+
 /*
  * etnaviv private data construction and destructions:
  */
@@ -52,6 +82,10 @@ etnaviv_alloc_private(struct device *dev, struct drm_device *drm)
 		return ERR_PTR(-ENOMEM);
 	}
 
+	priv->dma_coherent = etnaviv_is_dma_coherent(dev);
+
+	drm_info(drm, "%s is dma coherent\n", dev_name(dev));
+
 	return priv;
 }
 
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
index 9cd72948cfad..644e5712c050 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
@@ -46,6 +46,12 @@ struct etnaviv_drm_private {
 	struct xarray active_contexts;
 	u32 next_context_id;
 
+	/*
+	 * If true, the GPU is capable of snooping cpu cache. Here, it
+	 * also means that cache coherency is enforced by the hardware.
+	 */
+	bool dma_coherent;
+
 	/* list of GEM objects: */
 	struct mutex gem_lock;
 	struct list_head gem_list;
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
index b5f73502e3dd..39bdc3774f2d 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
@@ -343,6 +343,7 @@ void *etnaviv_gem_vmap(struct drm_gem_object *obj)
 static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
 {
 	struct page **pages;
+	pgprot_t prot;
 
 	lockdep_assert_held(&obj->lock);
 
@@ -350,8 +351,19 @@ static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
 	if (IS_ERR(pages))
 		return NULL;
 
-	return vmap(pages, obj->base.size >> PAGE_SHIFT,
-			VM_MAP, pgprot_writecombine(PAGE_KERNEL));
+	switch (obj->flags) {
+	case ETNA_BO_CACHED:
+		prot = PAGE_KERNEL;
+		break;
+	case ETNA_BO_UNCACHED:
+		prot = pgprot_noncached(PAGE_KERNEL);
+		break;
+	case ETNA_BO_WC:
+	default:
+		prot = pgprot_writecombine(PAGE_KERNEL);
+	}
+
+	return vmap(pages, obj->base.size >> PAGE_SHIFT, VM_MAP, prot);
 }
 
 static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
@@ -369,6 +381,7 @@ int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
 {
 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
 	struct drm_device *dev = obj->dev;
+	struct etnaviv_drm_private *priv = dev->dev_private;
 	bool write = !!(op & ETNA_PREP_WRITE);
 	int ret;
 
@@ -395,7 +408,7 @@ int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
 			return ret == 0 ? -ETIMEDOUT : ret;
 	}
 
-	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
+	if (!priv->dma_coherent && etnaviv_obj->flags & ETNA_BO_CACHED) {
 		dma_sync_sgtable_for_cpu(dev->dev, etnaviv_obj->sgt,
 					 etnaviv_op_to_dma_dir(op));
 		etnaviv_obj->last_cpu_prep_op = op;
@@ -408,8 +421,9 @@ int etnaviv_gem_cpu_fini(struct drm_gem_object *obj)
 {
 	struct drm_device *dev = obj->dev;
 	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
+	struct etnaviv_drm_private *priv = dev->dev_private;
 
-	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
+	if (!priv->dma_coherent && etnaviv_obj->flags & ETNA_BO_CACHED) {
 		/* fini without a prep is almost certainly a userspace error */
 		WARN_ON(etnaviv_obj->last_cpu_prep_op == 0);
 		dma_sync_sgtable_for_device(dev->dev, etnaviv_obj->sgt,
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
index 3524b5811682..754126992264 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
@@ -112,11 +112,16 @@ static const struct etnaviv_gem_ops etnaviv_gem_prime_ops = {
 struct drm_gem_object *etnaviv_gem_prime_import_sg_table(struct drm_device *dev,
 	struct dma_buf_attachment *attach, struct sg_table *sgt)
 {
+	struct etnaviv_drm_private *priv = dev->dev_private;
 	struct etnaviv_gem_object *etnaviv_obj;
 	size_t size = PAGE_ALIGN(attach->dmabuf->size);
+	u32 cache_flags = ETNA_BO_WC;
 	int ret, npages;
 
-	ret = etnaviv_gem_new_private(dev, size, ETNA_BO_WC,
+	if (priv->dma_coherent)
+		cache_flags = ETNA_BO_CACHED;
+
+	ret = etnaviv_gem_new_private(dev, size, cache_flags,
 				      &etnaviv_gem_prime_ops, &etnaviv_obj);
 	if (ret < 0)
 		return ERR_PTR(ret);
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index d6a21e97feb1..d99ac675ce8b 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -164,6 +164,10 @@ int etnaviv_gpu_get_param(struct etnaviv_gpu *gpu, u32 param, u64 *value)
 		*value = gpu->identity.eco_id;
 		break;
 
+	case ETNAVIV_PARAM_GPU_COHERENT:
+		*value = priv->dma_coherent;
+		break;
+
 	default:
 		DBG("%s: invalid param: %u", dev_name(gpu->dev), param);
 		return -EINVAL;
diff --git a/include/uapi/drm/etnaviv_drm.h b/include/uapi/drm/etnaviv_drm.h
index af024d90453d..76baf45d7158 100644
--- a/include/uapi/drm/etnaviv_drm.h
+++ b/include/uapi/drm/etnaviv_drm.h
@@ -77,6 +77,7 @@ struct drm_etnaviv_timespec {
 #define ETNAVIV_PARAM_GPU_PRODUCT_ID                0x1c
 #define ETNAVIV_PARAM_GPU_CUSTOMER_ID               0x1d
 #define ETNAVIV_PARAM_GPU_ECO_ID                    0x1e
+#define ETNAVIV_PARAM_GPU_COHERENT                  0x1f
 
 #define ETNA_MAX_PIPES 4
 
-- 
2.25.1

[PATCH v9 8/9] drm/etnaviv: Add a dedicated function to create the virtual master

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

After introducing the etnaviv_of_first_available_node() helper, the
creation of the virtual master platform device can also be simplified.
So, switch to etnaviv_create_virtual_master() function.

Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 43 ++++++++++++++++-----------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 1c9386e5a1b0..0ee7f641cee3 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -766,10 +766,32 @@ static void etnaviv_destroy_platform_device(struct platform_device **ppdev)
 	*ppdev = NULL;
 }
 
+static int etnaviv_create_virtual_master(void)
+{
+	struct platform_device **master = &etnaviv_platform_device;
+	struct device_node *np;
+
+	/*
+	 * If the DT contains at least one available GPU device, instantiate
+	 * the DRM platform device.
+	 */
+	np = etnaviv_of_first_available_node();
+	if (np) {
+		int ret;
+
+		of_node_put(np);
+
+		ret = etnaviv_create_platform_device("etnaviv", master);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static int __init etnaviv_init(void)
 {
 	int ret;
-	struct device_node *np;
 
 	etnaviv_validate_init();
 
@@ -785,22 +807,9 @@ static int __init etnaviv_init(void)
 	if (ret != 0)
 		goto unregister_platform_driver;
 
-	/*
-	 * If the DT contains at least one available GPU device, instantiate
-	 * the DRM platform device.
-	 */
-	for_each_compatible_node(np, NULL, "vivante,gc") {
-		if (!of_device_is_available(np))
-			continue;
-		of_node_put(np);
-
-		ret = etnaviv_create_platform_device("etnaviv",
-						     &etnaviv_platform_device);
-		if (ret)
-			goto unregister_platform_driver;
-
-		break;
-	}
+	ret = etnaviv_create_virtual_master();
+	if (ret)
+		goto unregister_platform_driver;
 
 	return ret;
 
-- 
2.25.1

[PATCH v9 9/9] drm/etnaviv: Clean up etnaviv_pdev_probe() function

[Sui Jingfeng]

From: Sui Jingfeng <suijingfeng@loongson.cn>

Add a dedicate function to do the DMA configuration to the virtual master.
Also replace the &pdev->dev with dev.

Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 65 +++++++++++++++------------
 1 file changed, 36 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 0ee7f641cee3..df4c21a17d9d 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -54,6 +54,40 @@ static bool etnaviv_is_dma_coherent(struct device *dev)
 	return coherent;
 }
 
+static int etnaviv_of_dma_configure(struct device *dev)
+{
+	struct device_node *first_node;
+
+	/*
+	 * PTA and MTLB can have 40 bit base addresses, but
+	 * unfortunately, an entry in the MTLB can only point to a
+	 * 32 bit base address of a STLB. Moreover, to initialize the
+	 * MMU we need a command buffer with a 32 bit address because
+	 * without an MMU there is only an indentity mapping between
+	 * the internal 32 bit addresses and the bus addresses.
+	 *
+	 * To make things easy, we set the dma_coherent_mask to 32
+	 * bit to make sure we are allocating the command buffers and
+	 * TLBs in the lower 4 GiB address space.
+	 */
+	if (dma_set_mask(dev, DMA_BIT_MASK(40)) ||
+	    dma_set_coherent_mask(dev, DMA_BIT_MASK(32))) {
+		dev_err(dev, "No suitable DMA available\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Apply the same DMA configuration to the virtual etnaviv
+	 * device as the GPU we found. This assumes that all Vivante
+	 * GPUs in the system share the same DMA constraints.
+	 */
+	first_node = etnaviv_of_first_available_node();
+	if (first_node)
+		of_dma_configure(dev, first_node, true);
+
+	return 0;
+}
+
 /*
  * etnaviv private data construction and destructions:
  */
@@ -663,7 +697,6 @@ static const struct component_master_ops etnaviv_master_ops = {
 static int etnaviv_pdev_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct device_node *first_node = NULL;
 	struct component_match *match = NULL;
 
 	if (!dev->platform_data) {
@@ -673,10 +706,7 @@ static int etnaviv_pdev_probe(struct platform_device *pdev)
 			if (!of_device_is_available(core_node))
 				continue;
 
-			if (!first_node)
-				first_node = core_node;
-
-			drm_of_component_match_add(&pdev->dev, &match,
+			drm_of_component_match_add(dev, &match,
 						   component_compare_of, core_node);
 		}
 	} else {
@@ -687,31 +717,8 @@ static int etnaviv_pdev_probe(struct platform_device *pdev)
 			component_match_add(dev, &match, component_compare_dev_name, names[i]);
 	}
 
-	/*
-	 * PTA and MTLB can have 40 bit base addresses, but
-	 * unfortunately, an entry in the MTLB can only point to a
-	 * 32 bit base address of a STLB. Moreover, to initialize the
-	 * MMU we need a command buffer with a 32 bit address because
-	 * without an MMU there is only an indentity mapping between
-	 * the internal 32 bit addresses and the bus addresses.
-	 *
-	 * To make things easy, we set the dma_coherent_mask to 32
-	 * bit to make sure we are allocating the command buffers and
-	 * TLBs in the lower 4 GiB address space.
-	 */
-	if (dma_set_mask(&pdev->dev, DMA_BIT_MASK(40)) ||
-	    dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32))) {
-		dev_dbg(&pdev->dev, "No suitable DMA available\n");
+	if (etnaviv_of_dma_configure(dev))
 		return -ENODEV;
-	}
-
-	/*
-	 * Apply the same DMA configuration to the virtual etnaviv
-	 * device as the GPU we found. This assumes that all Vivante
-	 * GPUs in the system share the same DMA constraints.
-	 */
-	if (first_node)
-		of_dma_configure(&pdev->dev, first_node, true);
 
 	return component_master_add_with_match(dev, &etnaviv_master_ops, match);
 }
-- 
2.25.1

Re: [PATCH v9 7/9] drm/etnaviv: Add support for the dma coherent device

[Sui Jingfeng]

Hi,

On 2023/6/14 10:47, Sui Jingfeng wrote:
> From: Sui Jingfeng <suijingfeng@loongson.cn>
>
> Loongson CPUs maintain cache coherency by hardware, which means that the
> data in the CPU cache is identical to the data in main system memory. As
> for the peripheral device, most of Loongson chips chose to define the
> peripherals as DMA coherent by default, device drivers do not need to
> maintain the coherency between a processor and an I/O device manually.
>
> There are exceptions, for LS2K1000 SoC, part of peripheral device can be
> configured as DMA non-coherent. But there is no released version of such
> firmware exist in the market. Peripherals of older LS2K1000 is also DMA
> non-coherent, but they are nearly outdated. So, those are trivial cases.
>
> Nevertheless, kernel space still need to do the probe work, because vivante
> GPU IP has been integrated into various platform. Hence, this patch add
> runtime detection code to probe if a specific GPU is DMA coherent, If the
> answer is yes, we are going to utilize such features. On Loongson platform,
> When a buffer is accessed by both the GPU and the CPU, the driver should
> prefer ETNA_BO_CACHED over ETNA_BO_WC.
>
> This patch also add a new parameter: etnaviv_param_gpu_coherent, which
> allow userspace to know if such a feature is available. Because
> write-combined BO is still preferred in some case, especially where don't
> need CPU read, for example, uploading shader bin.
>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
> ---
>   drivers/gpu/drm/etnaviv/etnaviv_drv.c       | 34 +++++++++++++++++++++
>   drivers/gpu/drm/etnaviv/etnaviv_drv.h       |  6 ++++
>   drivers/gpu/drm/etnaviv/etnaviv_gem.c       | 22 ++++++++++---
>   drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c |  7 ++++-
>   drivers/gpu/drm/etnaviv/etnaviv_gpu.c       |  4 +++
>   include/uapi/drm/etnaviv_drm.h              |  1 +
>   6 files changed, 69 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
> index 0a365e96d371..1c9386e5a1b0 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
> @@ -5,7 +5,9 @@
>   
>   #include <linux/component.h>
>   #include <linux/dma-mapping.h>
> +#include <linux/dma-map-ops.h>
>   #include <linux/module.h>
> +#include <linux/of_address.h>
>   #include <linux/of_platform.h>
>   #include <linux/uaccess.h>
>   
> @@ -24,6 +26,34 @@
>   #include "etnaviv_pci_drv.h"
>   #include "etnaviv_perfmon.h"
>   
> +static struct device_node *etnaviv_of_first_available_node(void)
> +{
> +	struct device_node *core_node;
> +
> +	for_each_compatible_node(core_node, NULL, "vivante,gc") {
> +		if (of_device_is_available(core_node))
> +			return core_node;
> +	}
> +
> +	return NULL;
> +}
> +
> +static bool etnaviv_is_dma_coherent(struct device *dev)
> +{
> +	struct device_node *np;
> +	bool coherent;
> +
> +	np = etnaviv_of_first_available_node();
> +	if (np) {
> +		coherent = of_dma_is_coherent(np);
> +		of_node_put(np);
> +	} else {
> +		coherent = dev_is_dma_coherent(dev);
> +	}
> +
> +	return coherent;
> +}
> +
>   /*
>    * etnaviv private data construction and destructions:
>    */
> @@ -52,6 +82,10 @@ etnaviv_alloc_private(struct device *dev, struct drm_device *drm)
>   		return ERR_PTR(-ENOMEM);
>   	}
>   
> +	priv->dma_coherent = etnaviv_is_dma_coherent(dev);
> +
> +	drm_info(drm, "%s is dma coherent\n", dev_name(dev));
> +

Here, we missing a if (priv->dma_coherent), sorry

```

     if (priv->dma_coherent)

            drm_info(drm, "%s is dma coherent\n", dev_name(dev));

```

>   	return priv;
>   }
>   
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> index 9cd72948cfad..644e5712c050 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> @@ -46,6 +46,12 @@ struct etnaviv_drm_private {
>   	struct xarray active_contexts;
>   	u32 next_context_id;
>   
> +	/*
> +	 * If true, the GPU is capable of snooping cpu cache. Here, it
> +	 * also means that cache coherency is enforced by the hardware.
> +	 */
> +	bool dma_coherent;
> +
>   	/* list of GEM objects: */
>   	struct mutex gem_lock;
>   	struct list_head gem_list;
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> index b5f73502e3dd..39bdc3774f2d 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> @@ -343,6 +343,7 @@ void *etnaviv_gem_vmap(struct drm_gem_object *obj)
>   static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
>   {
>   	struct page **pages;
> +	pgprot_t prot;
>   
>   	lockdep_assert_held(&obj->lock);
>   
> @@ -350,8 +351,19 @@ static void *etnaviv_gem_vmap_impl(struct etnaviv_gem_object *obj)
>   	if (IS_ERR(pages))
>   		return NULL;
>   
> -	return vmap(pages, obj->base.size >> PAGE_SHIFT,
> -			VM_MAP, pgprot_writecombine(PAGE_KERNEL));
> +	switch (obj->flags) {
> +	case ETNA_BO_CACHED:
> +		prot = PAGE_KERNEL;
> +		break;
> +	case ETNA_BO_UNCACHED:
> +		prot = pgprot_noncached(PAGE_KERNEL);
> +		break;
> +	case ETNA_BO_WC:
> +	default:
> +		prot = pgprot_writecombine(PAGE_KERNEL);
> +	}
> +
> +	return vmap(pages, obj->base.size >> PAGE_SHIFT, VM_MAP, prot);
>   }
>   
>   static inline enum dma_data_direction etnaviv_op_to_dma_dir(u32 op)
> @@ -369,6 +381,7 @@ int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
>   {
>   	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
>   	struct drm_device *dev = obj->dev;
> +	struct etnaviv_drm_private *priv = dev->dev_private;
>   	bool write = !!(op & ETNA_PREP_WRITE);
>   	int ret;
>   
> @@ -395,7 +408,7 @@ int etnaviv_gem_cpu_prep(struct drm_gem_object *obj, u32 op,
>   			return ret == 0 ? -ETIMEDOUT : ret;
>   	}
>   
> -	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
> +	if (!priv->dma_coherent && etnaviv_obj->flags & ETNA_BO_CACHED) {
>   		dma_sync_sgtable_for_cpu(dev->dev, etnaviv_obj->sgt,
>   					 etnaviv_op_to_dma_dir(op));
>   		etnaviv_obj->last_cpu_prep_op = op;
> @@ -408,8 +421,9 @@ int etnaviv_gem_cpu_fini(struct drm_gem_object *obj)
>   {
>   	struct drm_device *dev = obj->dev;
>   	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
> +	struct etnaviv_drm_private *priv = dev->dev_private;
>   
> -	if (etnaviv_obj->flags & ETNA_BO_CACHED) {
> +	if (!priv->dma_coherent && etnaviv_obj->flags & ETNA_BO_CACHED) {
>   		/* fini without a prep is almost certainly a userspace error */
>   		WARN_ON(etnaviv_obj->last_cpu_prep_op == 0);
>   		dma_sync_sgtable_for_device(dev->dev, etnaviv_obj->sgt,
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> index 3524b5811682..754126992264 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> @@ -112,11 +112,16 @@ static const struct etnaviv_gem_ops etnaviv_gem_prime_ops = {
>   struct drm_gem_object *etnaviv_gem_prime_import_sg_table(struct drm_device *dev,
>   	struct dma_buf_attachment *attach, struct sg_table *sgt)
>   {
> +	struct etnaviv_drm_private *priv = dev->dev_private;
>   	struct etnaviv_gem_object *etnaviv_obj;
>   	size_t size = PAGE_ALIGN(attach->dmabuf->size);
> +	u32 cache_flags = ETNA_BO_WC;
>   	int ret, npages;
>   
> -	ret = etnaviv_gem_new_private(dev, size, ETNA_BO_WC,
> +	if (priv->dma_coherent)
> +		cache_flags = ETNA_BO_CACHED;
> +
> +	ret = etnaviv_gem_new_private(dev, size, cache_flags,
>   				      &etnaviv_gem_prime_ops, &etnaviv_obj);
>   	if (ret < 0)
>   		return ERR_PTR(ret);
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> index d6a21e97feb1..d99ac675ce8b 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> @@ -164,6 +164,10 @@ int etnaviv_gpu_get_param(struct etnaviv_gpu *gpu, u32 param, u64 *value)
>   		*value = gpu->identity.eco_id;
>   		break;
>   
> +	case ETNAVIV_PARAM_GPU_COHERENT:
> +		*value = priv->dma_coherent;
> +		break;
> +
>   	default:
>   		DBG("%s: invalid param: %u", dev_name(gpu->dev), param);
>   		return -EINVAL;
> diff --git a/include/uapi/drm/etnaviv_drm.h b/include/uapi/drm/etnaviv_drm.h
> index af024d90453d..76baf45d7158 100644
> --- a/include/uapi/drm/etnaviv_drm.h
> +++ b/include/uapi/drm/etnaviv_drm.h
> @@ -77,6 +77,7 @@ struct drm_etnaviv_timespec {
>   #define ETNAVIV_PARAM_GPU_PRODUCT_ID                0x1c
>   #define ETNAVIV_PARAM_GPU_CUSTOMER_ID               0x1d
>   #define ETNAVIV_PARAM_GPU_ECO_ID                    0x1e
> +#define ETNAVIV_PARAM_GPU_COHERENT                  0x1f
>   
>   #define ETNA_MAX_PIPES 4
>   

-- 
Jingfeng