Nouveau - Jun 2014 - [PATCH v2 0/3] drm/nouveau: support for probing platform devices

This series adds support for probing platform devices on Nouveau, as well as
the DT bindings for GK20A. It doesn't enable the GPU yet on Tegra boards
since
a few extra things need to be supported before that.

Thanks to the input received for v1, this version is more self-contained and
shares less stuff between nouveau_drm and nouveau_platform. The major change
is that nouveau_platform is now a module of its own. The main reason for this
is that it allows us to register/unregister the driver from the module init
functions instead of parasiting the ones of nouveau_drm. It also makes it
simpler to build Nouveau without platform support at all.

Changes since v1:
* Moved the platform device driver to its own module. This allows it to be more
  self-contained and saves us the need to export too many functions from
  nouveau_drm and nouveau_platform.
* Register the DRM device without using the platform helpers, which is made
  possible by drm_dev_set_unique(). This allows us to catch and register the
  DRM device during platform probe.
* Fixed the clock names in the DT bindings.
* Removed the patches enabling GK20A on Venice2 and Jetson TK1 as support
  is not complete yet.

Alexandre Courbot (2):
  drm/nouveau: support for probing platform devices
  ARM: tegra: of: add GK20A device tree binding

Thierry Reding (1):
  ARM: tegra: add GK20A GPU to Tegra124 DT

 .../devicetree/bindings/gpu/nvidia,gk20a.txt       |  43 +++++
 arch/arm/boot/dts/tegra124.dtsi                    |  15 ++
 drivers/gpu/drm/nouveau/Kconfig                    |   8 +
 drivers/gpu/drm/nouveau/Makefile                   |   3 +
 drivers/gpu/drm/nouveau/nouveau_drm.c              |  56 +++++--
 drivers/gpu/drm/nouveau/nouveau_drm.h              |   3 +
 drivers/gpu/drm/nouveau/nouveau_platform.c         | 182 +++++++++++++++++++++
 7 files changed, 299 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpu/nvidia,gk20a.txt
 create mode 100644 drivers/gpu/drm/nouveau/nouveau_platform.c

-- 
2.0.0

Add a platform driver for Nouveau devices declared using the device tree
or platform data. This driver currently supports GK20A on Tegra
platforms and is only compiled for these platforms if Nouveau is
enabled.

Nouveau will probe the chip type itself using the BOOT0 register, so all
this driver really needs to do is to make sure the module is powered and
its clocks active before calling nouveau_drm_platform_probe().

Heavily based on work done by Thierry Reding.

Signed-off-by: Thierry Reding <treding at nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
---
 drivers/gpu/drm/nouveau/Kconfig            |   8 ++
 drivers/gpu/drm/nouveau/Makefile           |   3 +
 drivers/gpu/drm/nouveau/nouveau_drm.c      |  56 +++++++--
 drivers/gpu/drm/nouveau/nouveau_drm.h      |   3 +
 drivers/gpu/drm/nouveau/nouveau_platform.c | 182 +++++++++++++++++++++++++++++
 5 files changed, 241 insertions(+), 11 deletions(-)
 create mode 100644 drivers/gpu/drm/nouveau/nouveau_platform.c

diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig
index 637c29a33127..c0f83a40bd85 100644
--- a/drivers/gpu/drm/nouveau/Kconfig
+++ b/drivers/gpu/drm/nouveau/Kconfig
@@ -25,6 +25,14 @@ config DRM_NOUVEAU
 	help
 	  Choose this option for open-source nVidia support.
 
+config NOUVEAU_PLATFORM_DRIVER
+	tristate "Nouveau (nVidia) integrated GPUs"
+	depends on DRM_NOUVEAU
+	default y if ARCH_TEGRA
+	help
+	  Support for Nouveau platform driver, used for integrated GPUs as found
+	  on NVIDIA Tegra K1.
+
 config NOUVEAU_DEBUG
 	int "Maximum debug level"
 	depends on DRM_NOUVEAU
diff --git a/drivers/gpu/drm/nouveau/Makefile b/drivers/gpu/drm/nouveau/Makefile
index 2b6156d0e4b5..cd6e6a442b2d 100644
--- a/drivers/gpu/drm/nouveau/Makefile
+++ b/drivers/gpu/drm/nouveau/Makefile
@@ -348,3 +348,6 @@ nouveau-$(CONFIG_DRM_NOUVEAU_BACKLIGHT) +=
nouveau_backlight.o
 nouveau-$(CONFIG_DEBUG_FS) += nouveau_debugfs.o
 
 obj-$(CONFIG_DRM_NOUVEAU)+= nouveau.o
+
+# platform driver
+obj-$(CONFIG_NOUVEAU_PLATFORM_DRIVER) += nouveau_platform.o
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c
b/drivers/gpu/drm/nouveau/nouveau_drm.c
index ddd83756b9a2..16392026ce74 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -494,10 +494,9 @@ nouveau_drm_unload(struct drm_device *dev)
 	return 0;
 }
 
-static void
-nouveau_drm_remove(struct pci_dev *pdev)
+void
+nouveau_drm_device_remove(struct drm_device *dev)
 {
-	struct drm_device *dev = pci_get_drvdata(pdev);
 	struct nouveau_drm *drm = nouveau_drm(dev);
 	struct nouveau_object *device;
 
@@ -508,6 +507,15 @@ nouveau_drm_remove(struct pci_dev *pdev)
 	nouveau_object_ref(NULL, &device);
 	nouveau_object_debug();
 }
+EXPORT_SYMBOL(nouveau_drm_device_remove);
+
+static void
+nouveau_drm_remove(struct pci_dev *pdev)
+{
+	struct drm_device *dev = pci_get_drvdata(pdev);
+
+	nouveau_drm_device_remove(dev);
+}
 
 static int
 nouveau_do_suspend(struct drm_device *dev, bool runtime)
@@ -1003,24 +1011,50 @@ nouveau_drm_pci_driver = {
 	.driver.pm = &nouveau_pm_ops,
 };
 
-int nouveau_drm_platform_probe(struct platform_device *pdev)
+struct drm_device *
+nouveau_platform_device_create(struct platform_device *pdev)
 {
 	struct nouveau_device *device;
-	int ret;
+	struct drm_device *drm;
+	int err;
 
-	ret = nouveau_device_create(pdev, NOUVEAU_BUS_PLATFORM,
+	err = nouveau_device_create(pdev, NOUVEAU_BUS_PLATFORM,
 				    nouveau_platform_name(pdev),
 				    dev_name(&pdev->dev), nouveau_config,
 				    nouveau_debug, &device);
+	if (err)
+		return ERR_PTR(err);
 
-	ret = drm_platform_init(&driver, pdev);
-	if (ret) {
-		nouveau_object_ref(NULL, (struct nouveau_object **)&device);
-		return ret;
+	drm = drm_dev_alloc(&driver, &pdev->dev);
+	if (!drm) {
+		err = -ENOMEM;
+		goto err_free;
 	}
 
-	return ret;
+	err = drm_dev_set_unique(drm, "%s", dev_name(&pdev->dev));
+	if (err < 0)
+		goto err_free;
+
+	drm->platformdev = pdev;
+	err = drm_dev_register(drm, 0);
+	if (err < 0)
+		goto err_unref;
+
+	DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n",
+		 driver.name, driver.major, driver.minor, driver.patchlevel,
+		 driver.date, drm->primary->index);
+
+	return drm;
+
+err_unref:
+	drm_dev_unref(drm);
+
+err_free:
+	nouveau_object_ref(NULL, (struct nouveau_object **)&device);
+
+	return ERR_PTR(err);
 }
+EXPORT_SYMBOL(nouveau_platform_device_create);
 
 static int __init
 nouveau_drm_init(void)
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.h
b/drivers/gpu/drm/nouveau/nouveau_drm.h
index 7efbafaf7c1d..550a4ebb5411 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.h
@@ -157,6 +157,9 @@ nouveau_dev(struct drm_device *dev)
 int nouveau_pmops_suspend(struct device *);
 int nouveau_pmops_resume(struct device *);
 
+struct drm_device *nouveau_platform_device_create(struct platform_device
*pdev);
+void nouveau_drm_device_remove(struct drm_device *dev);
+
 #define NV_FATAL(cli, fmt, args...) nv_fatal((cli), fmt, ##args)
 #define NV_ERROR(cli, fmt, args...) nv_error((cli), fmt, ##args)
 #define NV_WARN(cli, fmt, args...) nv_warn((cli), fmt, ##args)
diff --git a/drivers/gpu/drm/nouveau/nouveau_platform.c
b/drivers/gpu/drm/nouveau/nouveau_platform.c
new file mode 100644
index 000000000000..94cf083978e8
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_platform.c
@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
"Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/reset.h>
+#include <linux/regulator/consumer.h>
+#include <linux/tegra-powergate.h>
+
+#include "nouveau_drm.h"
+
+struct nouveau_platform_gpu {
+	struct drm_device *drm;
+
+	struct reset_control *rst;
+	struct clk *clk;
+	struct clk *clk_pwr;
+
+	struct regulator *vdd;
+};
+
+static int nouveau_platform_power_up(struct nouveau_platform_gpu *gpu)
+{
+	int err;
+
+	err = regulator_enable(gpu->vdd);
+	if (err)
+		goto err_power;
+
+	err = clk_prepare_enable(gpu->clk);
+	if (err)
+		goto err_clk;
+	err = clk_prepare_enable(gpu->clk_pwr);
+	if (err)
+		goto err_clk_pwr;
+	clk_set_rate(gpu->clk_pwr, 204000000);
+	udelay(10);
+
+	reset_control_assert(gpu->rst);
+	udelay(10);
+
+	err = tegra_powergate_remove_clamping(TEGRA_POWERGATE_3D);
+	if (err)
+		goto err_clamp;
+	udelay(10);
+
+	reset_control_deassert(gpu->rst);
+	udelay(10);
+
+	return 0;
+
+err_clamp:
+	clk_disable_unprepare(gpu->clk_pwr);
+err_clk_pwr:
+	clk_disable_unprepare(gpu->clk);
+err_clk:
+	regulator_disable(gpu->vdd);
+err_power:
+	return err;
+}
+
+static int nouveau_platform_power_down(struct nouveau_platform_gpu *gpu)
+{
+	int err;
+
+	reset_control_assert(gpu->rst);
+	udelay(10);
+
+	clk_disable_unprepare(gpu->clk_pwr);
+	clk_disable_unprepare(gpu->clk);
+	udelay(10);
+
+	err = regulator_disable(gpu->vdd);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int nouveau_platform_probe(struct platform_device *pdev)
+{
+	struct nouveau_platform_gpu *gpu;
+	int err;
+
+	gpu = devm_kzalloc(&pdev->dev, sizeof(*gpu), GFP_KERNEL);
+	if (!gpu)
+		return -ENOMEM;
+
+	gpu->vdd = devm_regulator_get(&pdev->dev, "vdd");
+	if (IS_ERR(gpu->vdd))
+		return PTR_ERR(gpu->vdd);
+
+	gpu->rst = devm_reset_control_get(&pdev->dev, "gpu");
+	if (IS_ERR(gpu->rst))
+		return PTR_ERR(gpu->rst);
+
+	gpu->clk = devm_clk_get(&pdev->dev, "gpu");
+	if (IS_ERR(gpu->clk))
+		return PTR_ERR(gpu->clk);
+
+	gpu->clk_pwr = devm_clk_get(&pdev->dev, "pwr");
+	if (IS_ERR(gpu->clk_pwr))
+		return PTR_ERR(gpu->clk_pwr);
+
+	err = nouveau_platform_power_up(gpu);
+	if (err)
+		return err;
+
+	platform_set_drvdata(pdev, gpu);
+
+	gpu->drm = nouveau_platform_device_create(pdev);
+	if (IS_ERR(gpu->drm)) {
+		err = PTR_ERR(gpu->drm);
+		goto power_down;
+	}
+
+	return 0;
+
+power_down:
+	nouveau_platform_power_down(gpu);
+
+	return err;
+}
+
+static int nouveau_platform_remove(struct platform_device *pdev)
+{
+	struct nouveau_platform_gpu *gpu = platform_get_drvdata(pdev);
+	struct drm_device *drm_dev = gpu->drm;
+	int err;
+
+	nouveau_drm_device_remove(drm_dev);
+
+	err = nouveau_platform_power_down(gpu);
+
+	return err;
+}
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id nouveau_platform_match[] = {
+	{ .compatible = "nvidia,gk20a" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, nouveau_platform_match);
+#endif
+
+struct platform_driver nouveau_platform_driver = {
+	.driver = {
+		.name = "nouveau",
+		.of_match_table = of_match_ptr(nouveau_platform_match),
+	},
+	.probe = nouveau_platform_probe,
+	.remove = nouveau_platform_remove,
+};
+
+module_platform_driver(nouveau_platform_driver);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL and additional rights");
-- 
2.0.0

Add the device tree binding documentation for the GK20A GPU used in
Tegra K1 SoCs.

Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
Acked-by: Stephen Warren <swarren at nvidia.com>
---
 .../devicetree/bindings/gpu/nvidia,gk20a.txt       | 43 ++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpu/nvidia,gk20a.txt

diff --git a/Documentation/devicetree/bindings/gpu/nvidia,gk20a.txt
b/Documentation/devicetree/bindings/gpu/nvidia,gk20a.txt
new file mode 100644
index 000000000000..23bfe8e1f7cc
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpu/nvidia,gk20a.txt
@@ -0,0 +1,43 @@
+NVIDIA GK20A Graphics Processing Unit
+
+Required properties:
+- compatible: "nvidia,<chip>-<gpu>"
+  Currently recognized values:
+  - nvidia,tegra124-gk20a
+- reg: Physical base address and length of the controller's registers.
+  Must contain two entries:
+  - first entry for bar0
+  - second entry for bar1
+- interrupts: Must contain an entry for each entry in interrupt-names.
+  See ../interrupt-controller/interrupts.txt for details.
+- interrupt-names: Must include the following entries:
+  - stall
+  - nonstall
+- vdd-supply: regulator for supply voltage.
+- clocks: Must contain an entry for each entry in clock-names.
+  See ../clocks/clock-bindings.txt for details.
+- clock-names: Must include the following entries:
+  - gpu
+  - pwr
+- resets: Must contain an entry for each entry in reset-names.
+  See ../reset/reset.txt for details.
+- reset-names: Must include the following entries:
+  - gpu
+
+Example:
+
+	gpu at 0,57000000 {
+		compatible = "nvidia,gk20a";
+		reg = <0x0 0x57000000 0x0 0x01000000>,
+		      <0x0 0x58000000 0x0 0x01000000>;
+		interrupts = <GIC_SPI 157 IRQ_TYPE_LEVEL_HIGH>,
+			     <GIC_SPI 158 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-names = "stall", "nonstall";
+		vdd-supply = <&vdd_gpu>;
+		clocks = <&tegra_car TEGRA124_CLK_GPU>,
+			 <&tegra_car TEGRA124_CLK_PLL_P_OUT5>;
+		clock-names = "gpu", "pwr";
+		resets = <&tegra_car 184>;
+		reset-names = "gpu";
+		status = "disabled";
+	};
-- 
2.0.0

From: Thierry Reding <treding at nvidia.com>

Add the GK20A device node to Tegra124's device tree.

Signed-off-by: Thierry Reding <treding at nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
---
 arch/arm/boot/dts/tegra124.dtsi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm/boot/dts/tegra124.dtsi b/arch/arm/boot/dts/tegra124.dtsi
index 6e6bc4e8185c..09321f10e8ea 100644
--- a/arch/arm/boot/dts/tegra124.dtsi
+++ b/arch/arm/boot/dts/tegra124.dtsi
@@ -102,6 +102,21 @@
 			(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
 	};
 
+	gpu at 0,57000000 {
+		compatible = "nvidia,gk20a";
+		reg = <0x0 0x57000000 0x0 0x01000000>,
+		      <0x0 0x58000000 0x0 0x01000000>;
+		interrupts = <GIC_SPI 157 IRQ_TYPE_LEVEL_HIGH>,
+			     <GIC_SPI 158 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-names = "stall", "nonstall";
+		clocks = <&tegra_car TEGRA124_CLK_GPU>,
+			 <&tegra_car TEGRA124_CLK_PLL_P_OUT5>;
+		clock-names = "gpu", "pwr";
+		resets = <&tegra_car 184>;
+		reset-names = "gpu";
+		status = "disabled";
+	};
+
 	timer at 0,60005000 {
 		compatible = "nvidia,tegra124-timer",
"nvidia,tegra20-timer";
 		reg = <0x0 0x60005000 0x0 0x400>;
-- 
2.0.0