[PATCH RFC v3 2/6] drm/sprd: add Unisoc's drm kms master

[Kevin Tang]

From: Kevin Tang <kevin.tang@xxxxxxxxxx>

Adds drm support for the Unisoc's display subsystem.

This is drm device and gem driver. This driver provides support for the
Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher.

Cc: Orson Zhai <orsonzhai@xxxxxxxxx>
Cc: Baolin Wang <baolin.wang@xxxxxxxxxx>
Cc: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
Signed-off-by: Kevin Tang <kevin.tang@xxxxxxxxxx>
---
 drivers/gpu/drm/Kconfig         |   2 +
 drivers/gpu/drm/Makefile        |   1 +
 drivers/gpu/drm/sprd/Kconfig    |  14 ++
 drivers/gpu/drm/sprd/Makefile   |   7 +
 drivers/gpu/drm/sprd/sprd_drm.c | 292 ++++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/sprd/sprd_drm.h |  16 +++
 6 files changed, 332 insertions(+)
 create mode 100644 drivers/gpu/drm/sprd/Kconfig
 create mode 100644 drivers/gpu/drm/sprd/Makefile
 create mode 100644 drivers/gpu/drm/sprd/sprd_drm.c
 create mode 100644 drivers/gpu/drm/sprd/sprd_drm.h

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index bfdadc3..cead12c 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -387,6 +387,8 @@ source "drivers/gpu/drm/aspeed/Kconfig"
 
 source "drivers/gpu/drm/mcde/Kconfig"
 
+source "drivers/gpu/drm/sprd/Kconfig"
+
 # Keep legacy drivers last
 
 menuconfig DRM_LEGACY
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 9f1c7c4..85ca211 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -122,3 +122,4 @@ obj-$(CONFIG_DRM_LIMA)  += lima/
 obj-$(CONFIG_DRM_PANFROST) += panfrost/
 obj-$(CONFIG_DRM_ASPEED_GFX) += aspeed/
 obj-$(CONFIG_DRM_MCDE) += mcde/
+obj-$(CONFIG_DRM_SPRD) += sprd/
diff --git a/drivers/gpu/drm/sprd/Kconfig b/drivers/gpu/drm/sprd/Kconfig
new file mode 100644
index 0000000..79f286b
--- /dev/null
+++ b/drivers/gpu/drm/sprd/Kconfig
@@ -0,0 +1,14 @@
+config DRM_SPRD
+	tristate "DRM Support for Unisoc SoCs Platform"
+	depends on ARCH_SPRD
+	depends on DRM && OF
+	select DRM_KMS_HELPER
+	select DRM_GEM_CMA_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_MIPI_DSI
+	select DRM_PANEL
+	select VIDEOMODE_HELPERS
+	select BACKLIGHT_CLASS_DEVICE
+	help
+	  Choose this option if you have a Unisoc chipsets.
+	  If M is selected the module will be called sprd-drm.
\ No newline at end of file
diff --git a/drivers/gpu/drm/sprd/Makefile b/drivers/gpu/drm/sprd/Makefile
new file mode 100644
index 0000000..63b8751
--- /dev/null
+++ b/drivers/gpu/drm/sprd/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ccflags-y += -Iinclude/drm
+
+subdir-ccflags-y += -I$(src)
+
+obj-y := sprd_drm.o
diff --git a/drivers/gpu/drm/sprd/sprd_drm.c b/drivers/gpu/drm/sprd/sprd_drm.c
new file mode 100644
index 0000000..7cac098
--- /dev/null
+++ b/drivers/gpu/drm/sprd/sprd_drm.c
@@ -0,0 +1,292 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Unisoc Inc.
+ */
+
+#include <linux/component.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_graph.h>
+#include <linux/of_platform.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include "sprd_drm.h"
+
+#define DRIVER_NAME	"sprd"
+#define DRIVER_DESC	"Spreadtrum SoCs' DRM Driver"
+#define DRIVER_DATE	"20191101"
+#define DRIVER_MAJOR	1
+#define DRIVER_MINOR	0
+
+static const struct drm_mode_config_helper_funcs sprd_drm_mode_config_helper = {
+	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
+};
+
+static const struct drm_mode_config_funcs sprd_drm_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static void sprd_drm_mode_config_init(struct drm_device *drm)
+{
+	drm_mode_config_init(drm);
+
+	drm->mode_config.min_width = 0;
+	drm->mode_config.min_height = 0;
+	drm->mode_config.max_width = 8192;
+	drm->mode_config.max_height = 8192;
+	drm->mode_config.allow_fb_modifiers = true;
+
+	drm->mode_config.funcs = &sprd_drm_mode_config_funcs;
+	drm->mode_config.helper_private = &sprd_drm_mode_config_helper;
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(sprd_drm_fops);
+
+static struct drm_driver sprd_drm_drv = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+	.fops			= &sprd_drm_fops,
+
+	/* GEM Operations */
+  	DRM_GEM_CMA_VMAP_DRIVER_OPS,
+
+	.name			= DRIVER_NAME,
+	.desc			= DRIVER_DESC,
+	.date			= DRIVER_DATE,
+	.major			= DRIVER_MAJOR,
+	.minor			= DRIVER_MINOR,
+};
+
+static int sprd_drm_bind(struct device *dev)
+{
+	struct drm_device *drm;
+	struct sprd_drm *sprd;
+	int err;
+
+	drm = drm_dev_alloc(&sprd_drm_drv, dev);
+	if (IS_ERR(drm))
+		return PTR_ERR(drm);
+
+	dev_set_drvdata(dev, drm);
+
+	sprd = devm_kzalloc(drm->dev, sizeof(*sprd), GFP_KERNEL);
+	if (!sprd) {
+		err = -ENOMEM;
+		goto err_free_drm;
+	}
+	drm->dev_private = sprd;
+
+	sprd_drm_mode_config_init(drm);
+
+	/* bind and init sub drivers */
+	err = component_bind_all(drm->dev, drm);
+	if (err) {
+		DRM_ERROR("failed to bind all component.\n");
+		goto err_dc_cleanup;
+	}
+
+	/* vblank init */
+	err = drm_vblank_init(drm, drm->mode_config.num_crtc);
+	if (err) {
+		DRM_ERROR("failed to initialize vblank.\n");
+		goto err_unbind_all;
+	}
+	/* with irq_enabled = true, we can use the vblank feature. */
+	drm->irq_enabled = true;
+
+	/* reset all the states of crtc/plane/encoder/connector */
+	drm_mode_config_reset(drm);
+
+	/* init kms poll for handling hpd */
+	drm_kms_helper_poll_init(drm);
+
+	err = drm_dev_register(drm, 0);
+	if (err < 0)
+		goto err_kms_helper_poll_fini;
+
+	return 0;
+
+err_kms_helper_poll_fini:
+	drm_kms_helper_poll_fini(drm);
+err_unbind_all:
+	component_unbind_all(drm->dev, drm);
+err_dc_cleanup:
+	drm_mode_config_cleanup(drm);
+err_free_drm:
+	drm_dev_put(drm);
+	return err;
+}
+
+static void sprd_drm_unbind(struct device *dev)
+{
+	drm_put_dev(dev_get_drvdata(dev));
+}
+
+static const struct component_master_ops drm_component_ops = {
+	.bind = sprd_drm_bind,
+	.unbind = sprd_drm_unbind,
+};
+
+static int compare_of(struct device *dev, void *data)
+{
+	struct device_node *np = data;
+
+	DRM_DEBUG("compare %s\n", np->full_name);
+
+	return dev->of_node == np;
+}
+
+static int sprd_drm_component_probe(struct device *dev,
+			   const struct component_master_ops *m_ops)
+{
+	struct device_node *ep, *port, *remote;
+	struct component_match *match = NULL;
+	int i;
+
+	if (!dev->of_node)
+		return -EINVAL;
+
+	/*
+	 * Bind the crtc's ports first, so that drm_of_find_possible_crtcs()
+	 * called from encoder's .bind callbacks works as expected
+	 */
+	for (i = 0; ; i++) {
+		port = of_parse_phandle(dev->of_node, "ports", i);
+		if (!port)
+			break;
+
+		if (!of_device_is_available(port->parent)) {
+			of_node_put(port);
+			continue;
+		}
+
+		component_match_add(dev, &match, compare_of, port->parent);
+		of_node_put(port);
+	}
+
+	if (i == 0) {
+		dev_err(dev, "missing 'ports' property\n");
+		return -ENODEV;
+	}
+
+	if (!match) {
+		dev_err(dev, "no available port\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * For bound crtcs, bind the encoders attached to their remote endpoint
+	 */
+	for (i = 0; ; i++) {
+		port = of_parse_phandle(dev->of_node, "ports", i);
+		if (!port)
+			break;
+
+		if (!of_device_is_available(port->parent)) {
+			of_node_put(port);
+			continue;
+		}
+
+		for_each_child_of_node(port, ep) {
+			remote = of_graph_get_remote_port_parent(ep);
+			if (!remote || !of_device_is_available(remote)) {
+				of_node_put(remote);
+				continue;
+			} else if (!of_device_is_available(remote->parent)) {
+				dev_warn(dev, "parent device of %s is not available\n",
+					 remote->full_name);
+				of_node_put(remote);
+				continue;
+			}
+
+			component_match_add(dev, &match, compare_of, remote);
+			of_node_put(remote);
+		}
+		of_node_put(port);
+	}
+
+	return component_master_add_with_match(dev, m_ops, match);
+}
+
+static int sprd_drm_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	ret = dma_set_mask_and_coherent(&pdev->dev, ~0);
+	if (ret) {
+		DRM_ERROR("dma_set_mask_and_coherent failed (%d)\n", ret);
+		return ret;
+	}
+
+	return sprd_drm_component_probe(&pdev->dev, &drm_component_ops);
+}
+
+static int sprd_drm_remove(struct platform_device *pdev)
+{
+	component_master_del(&pdev->dev, &drm_component_ops);
+	return 0;
+}
+
+static void sprd_drm_shutdown(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+
+	if (!drm) {
+		DRM_WARN("drm device is not available, no shutdown\n");
+		return;
+	}
+
+	drm_atomic_helper_shutdown(drm);
+}
+
+static const struct of_device_id drm_match_table[] = {
+	{ .compatible = "sprd,display-subsystem", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, drm_match_table);
+
+static struct platform_driver sprd_drm_driver = {
+	.probe = sprd_drm_probe,
+	.remove = sprd_drm_remove,
+	.shutdown = sprd_drm_shutdown,
+	.driver = {
+		.name = "sprd-drm-drv",
+		.of_match_table = drm_match_table,
+	},
+};
+
+static struct platform_driver *sprd_drm_drivers[]  = {
+	&sprd_drm_driver,
+};
+
+static int __init sprd_drm_init(void)
+{
+	int ret;
+
+	ret = platform_register_drivers(sprd_drm_drivers,
+					ARRAY_SIZE(sprd_drm_drivers));
+	return ret;
+}
+
+static void __exit sprd_drm_exit(void)
+{
+	platform_unregister_drivers(sprd_drm_drivers,
+				    ARRAY_SIZE(sprd_drm_drivers));
+}
+
+module_init(sprd_drm_init);
+module_exit(sprd_drm_exit);
+
+MODULE_AUTHOR("Leon He <leon.he@xxxxxxxxxx>");
+MODULE_AUTHOR("Kevin Tang <kevin.tang@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Unisoc DRM KMS Master Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/sprd/sprd_drm.h b/drivers/gpu/drm/sprd/sprd_drm.h
new file mode 100644
index 0000000..137cb27
--- /dev/null
+++ b/drivers/gpu/drm/sprd/sprd_drm.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Unisoc Inc.
+ */
+
+#ifndef _SPRD_DRM_H_
+#define _SPRD_DRM_H_
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_print.h>
+
+struct sprd_drm {
+	struct drm_device *drm;
+};
+
+#endif /* _SPRD_DRM_H_ */
-- 
2.7.4