drm/imx: Add initial support for DCSS on iMX8MQ

This adds initial support for iMX8MQ's Display Controller Subsystem (DCSS).
Some of its capabilities include:
 * 4K@60fps;
 * HDR10;
 * one graphics and 2 video pipelines;
 * on-the-fly decompression of compressed video and graphics;

The reference manual can be found here:
https://www.nxp.com/webapp/Download?colCode=IMX8MDQLQRM

The current patch adds only basic functionality: one primary plane for
graphics, linear, tiled and super-tiled buffers support (no graphics
decompression yet), no HDR10 and no video planes.

Video planes support and HDR10 will be added in subsequent patches once
per-plane de-gamma/CSC/gamma support is in.

Signed-off-by: Laurentiu Palcu <laurentiu.palcu@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200731081836.3048-3-laurentiu.palcu@oss.nxp.com

1 files changed, 177 insertions, 0 deletions

diff --git a/drivers/gpu/drm/imx/dcss/dcss-kms.c b/drivers/gpu/drm/imx/dcss/dcss-kms.c
new file mode 100644
index 000000000000..3ca49d0a3e61
--- /dev/null
+++ b/drivers/gpu/drm/imx/dcss/dcss-kms.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include "dcss-dev.h"
+#include "dcss-kms.h"
+
+DEFINE_DRM_GEM_CMA_FOPS(dcss_cma_fops);
+
+static const struct drm_mode_config_funcs dcss_drm_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create,
+	.output_poll_changed = drm_fb_helper_output_poll_changed,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static struct drm_driver dcss_kms_driver = {
+	.driver_features	= DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
+	.gem_free_object_unlocked = drm_gem_cma_free_object,
+	.gem_vm_ops		= &drm_gem_cma_vm_ops,
+	.dumb_create		= drm_gem_cma_dumb_create,
+
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_import	= drm_gem_prime_import,
+	.gem_prime_export	= drm_gem_prime_export,
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
+	.fops			= &dcss_cma_fops,
+	.name			= "imx-dcss",
+	.desc			= "i.MX8MQ Display Subsystem",
+	.date			= "20190917",
+	.major			= 1,
+	.minor			= 0,
+	.patchlevel		= 0,
+};
+
+static const struct drm_mode_config_helper_funcs dcss_mode_config_helpers = {
+	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
+};
+
+static void dcss_kms_mode_config_init(struct dcss_kms_dev *kms)
+{
+	struct drm_mode_config *config = &kms->base.mode_config;
+
+	drm_mode_config_init(&kms->base);
+
+	config->min_width = 1;
+	config->min_height = 1;
+	config->max_width = 4096;
+	config->max_height = 4096;
+	config->allow_fb_modifiers = true;
+	config->normalize_zpos = true;
+
+	config->funcs = &dcss_drm_mode_config_funcs;
+	config->helper_private = &dcss_mode_config_helpers;
+}
+
+static const struct drm_encoder_funcs dcss_kms_simple_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
+static int dcss_kms_setup_encoder(struct dcss_kms_dev *kms)
+{
+	struct drm_device *ddev = &kms->base;
+	struct drm_encoder *encoder = &kms->encoder;
+	struct drm_crtc *crtc = (struct drm_crtc *)&kms->crtc;
+	struct drm_panel *panel;
+	struct drm_bridge *bridge;
+	int ret;
+
+	ret = drm_of_find_panel_or_bridge(ddev->dev->of_node, 0, 0,
+					  &panel, &bridge);
+	if (ret)
+		return ret;
+
+	if (!bridge) {
+		dev_err(ddev->dev, "No bridge found %d.\n", ret);
+		return -ENODEV;
+	}
+
+	encoder->possible_crtcs = drm_crtc_mask(crtc);
+
+	ret = drm_encoder_init(&kms->base, encoder,
+			       &dcss_kms_simple_encoder_funcs,
+			       DRM_MODE_ENCODER_NONE, NULL);
+	if (ret) {
+		dev_err(ddev->dev, "Failed initializing encoder %d.\n", ret);
+		return ret;
+	}
+
+	return drm_bridge_attach(encoder, bridge, NULL, 0);
+}
+
+struct dcss_kms_dev *dcss_kms_attach(struct dcss_dev *dcss)
+{
+	struct dcss_kms_dev *kms;
+	struct drm_device *drm;
+	struct dcss_crtc *crtc;
+	int ret;
+
+	kms = devm_drm_dev_alloc(dcss->dev, &dcss_kms_driver,
+				 struct dcss_kms_dev, base);
+	if (IS_ERR(kms))
+		return kms;
+
+	drm = &kms->base;
+	crtc = &kms->crtc;
+
+	drm->dev_private = dcss;
+
+	dcss_kms_mode_config_init(kms);
+
+	ret = drm_vblank_init(drm, 1);
+	if (ret)
+		goto cleanup_mode_config;
+
+	drm->irq_enabled = true;
+
+	ret = dcss_crtc_init(crtc, drm);
+	if (ret)
+		goto cleanup_mode_config;
+
+	ret = dcss_kms_setup_encoder(kms);
+	if (ret)
+		goto cleanup_crtc;
+
+	drm_mode_config_reset(drm);
+
+	drm_kms_helper_poll_init(drm);
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto cleanup_crtc;
+
+	drm_fbdev_generic_setup(drm, 32);
+
+	return kms;
+
+cleanup_crtc:
+	drm_kms_helper_poll_fini(drm);
+	dcss_crtc_deinit(crtc, drm);
+
+cleanup_mode_config:
+	drm_mode_config_cleanup(drm);
+	drm->dev_private = NULL;
+
+	return ERR_PTR(ret);
+}
+
+void dcss_kms_detach(struct dcss_kms_dev *kms)
+{
+	struct drm_device *drm = &kms->base;
+
+	drm_dev_unregister(drm);
+	drm_kms_helper_poll_fini(drm);
+	drm_atomic_helper_shutdown(drm);
+	drm_crtc_vblank_off(&kms->crtc.base);
+	drm->irq_enabled = false;
+	drm_mode_config_cleanup(drm);
+	dcss_crtc_deinit(&kms->crtc, drm);
+	drm->dev_private = NULL;
+}