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

drivers/gpu/drm/imx/Kconfig

@@ -39,3 +39,5 @@ config DRM_IMX_HDMI
 	depends on DRM_IMX
 	help
 	  Choose this if you want to use HDMI on i.MX6.
+
+source "drivers/gpu/drm/imx/dcss/Kconfig"

drivers/gpu/drm/imx/Makefile

@@ -9,3 +9,4 @@ obj-$(CONFIG_DRM_IMX_TVE) += imx-tve.o
 obj-$(CONFIG_DRM_IMX_LDB) += imx-ldb.o
 
 obj-$(CONFIG_DRM_IMX_HDMI) += dw_hdmi-imx.o
+obj-$(CONFIG_DRM_IMX_DCSS) += dcss/

drivers/gpu/drm/imx/dcss/Kconfig

+config DRM_IMX_DCSS
+	tristate "i.MX8MQ DCSS"
+	select IMX_IRQSTEER
+	select DRM_KMS_CMA_HELPER
+	select VIDEOMODE_HELPERS
+	depends on DRM && ARCH_MXC
+	help
+	  Choose this if you have a NXP i.MX8MQ based system and want to use the
+	  Display Controller Subsystem. This option enables DCSS support.

drivers/gpu/drm/imx/dcss/Makefile

+imx-dcss-objs := dcss-drv.o dcss-dev.o dcss-blkctl.o dcss-ctxld.o dcss-dtg.o \
+				 dcss-ss.o dcss-dpr.o dcss-scaler.o dcss-kms.o dcss-crtc.o \
+				 dcss-plane.o
+
+obj-$(CONFIG_DRM_IMX_DCSS) += imx-dcss.o
+

drivers/gpu/drm/imx/dcss/dcss-blkctl.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#include "dcss-dev.h"
+
+#define DCSS_BLKCTL_RESET_CTRL		0x00
+#define   B_CLK_RESETN			BIT(0)
+#define   APB_CLK_RESETN		BIT(1)
+#define   P_CLK_RESETN			BIT(2)
+#define   RTR_CLK_RESETN		BIT(4)
+#define DCSS_BLKCTL_CONTROL0		0x10
+#define   HDMI_MIPI_CLK_SEL		BIT(0)
+#define   DISPMIX_REFCLK_SEL_POS	4
+#define   DISPMIX_REFCLK_SEL_MASK	GENMASK(5, 4)
+#define   DISPMIX_PIXCLK_SEL		BIT(8)
+#define   HDMI_SRC_SECURE_EN		BIT(16)
+
+struct dcss_blkctl {
+	struct dcss_dev *dcss;
+	void __iomem *base_reg;
+};
+
+void dcss_blkctl_cfg(struct dcss_blkctl *blkctl)
+{
+	if (blkctl->dcss->hdmi_output)
+		dcss_writel(0, blkctl->base_reg + DCSS_BLKCTL_CONTROL0);
+	else
+		dcss_writel(DISPMIX_PIXCLK_SEL,
+			    blkctl->base_reg + DCSS_BLKCTL_CONTROL0);
+
+	dcss_set(B_CLK_RESETN | APB_CLK_RESETN | P_CLK_RESETN | RTR_CLK_RESETN,
+		 blkctl->base_reg + DCSS_BLKCTL_RESET_CTRL);
+}
+
+int dcss_blkctl_init(struct dcss_dev *dcss, unsigned long blkctl_base)
+{
+	struct dcss_blkctl *blkctl;
+
+	blkctl = kzalloc(sizeof(*blkctl), GFP_KERNEL);
+	if (!blkctl)
+		return -ENOMEM;
+
+	blkctl->base_reg = ioremap(blkctl_base, SZ_4K);
+	if (!blkctl->base_reg) {
+		dev_err(dcss->dev, "unable to remap BLK CTRL base\n");
+		kfree(blkctl);
+		return -ENOMEM;
+	}
+
+	dcss->blkctl = blkctl;
+	blkctl->dcss = dcss;
+
+	dcss_blkctl_cfg(blkctl);
+
+	return 0;
+}
+
+void dcss_blkctl_exit(struct dcss_blkctl *blkctl)
+{
+	if (blkctl->base_reg)
+		iounmap(blkctl->base_reg);
+
+	kfree(blkctl);
+}

drivers/gpu/drm/imx/dcss/dcss-crtc.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_vblank.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "dcss-dev.h"
+#include "dcss-kms.h"
+
+static int dcss_enable_vblank(struct drm_crtc *crtc)
+{
+	struct dcss_crtc *dcss_crtc = container_of(crtc, struct dcss_crtc,
+						   base);
+	struct dcss_dev *dcss = crtc->dev->dev_private;
+
+	dcss_dtg_vblank_irq_enable(dcss->dtg, true);
+
+	dcss_dtg_ctxld_kick_irq_enable(dcss->dtg, true);
+
+	enable_irq(dcss_crtc->irq);
+
+	return 0;
+}
+
+static void dcss_disable_vblank(struct drm_crtc *crtc)
+{
+	struct dcss_crtc *dcss_crtc = container_of(crtc, struct dcss_crtc,
+						   base);
+	struct dcss_dev *dcss = dcss_crtc->base.dev->dev_private;
+
+	disable_irq_nosync(dcss_crtc->irq);
+
+	dcss_dtg_vblank_irq_enable(dcss->dtg, false);
+
+	if (dcss_crtc->disable_ctxld_kick_irq)
+		dcss_dtg_ctxld_kick_irq_enable(dcss->dtg, false);
+}
+
+static const struct drm_crtc_funcs dcss_crtc_funcs = {
+	.set_config = drm_atomic_helper_set_config,
+	.destroy = drm_crtc_cleanup,
+	.page_flip = drm_atomic_helper_page_flip,
+	.reset = drm_atomic_helper_crtc_reset,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank = dcss_enable_vblank,
+	.disable_vblank = dcss_disable_vblank,
+};
+
+static void dcss_crtc_atomic_begin(struct drm_crtc *crtc,
+				   struct drm_crtc_state *old_crtc_state)
+{
+	drm_crtc_vblank_on(crtc);
+}
+
+static void dcss_crtc_atomic_flush(struct drm_crtc *crtc,
+				   struct drm_crtc_state *old_crtc_state)
+{
+	struct dcss_crtc *dcss_crtc = container_of(crtc, struct dcss_crtc,
+						   base);
+	struct dcss_dev *dcss = dcss_crtc->base.dev->dev_private;
+
+	spin_lock_irq(&crtc->dev->event_lock);
+	if (crtc->state->event) {
+		WARN_ON(drm_crtc_vblank_get(crtc));
+		drm_crtc_arm_vblank_event(crtc, crtc->state->event);
+		crtc->state->event = NULL;
+	}
+	spin_unlock_irq(&crtc->dev->event_lock);
+
+	if (dcss_dtg_is_enabled(dcss->dtg))
+		dcss_ctxld_enable(dcss->ctxld);
+}
+
+static void dcss_crtc_atomic_enable(struct drm_crtc *crtc,
+				    struct drm_crtc_state *old_crtc_state)
+{
+	struct dcss_crtc *dcss_crtc = container_of(crtc, struct dcss_crtc,
+						   base);
+	struct dcss_dev *dcss = dcss_crtc->base.dev->dev_private;
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+	struct drm_display_mode *old_mode = &old_crtc_state->adjusted_mode;
+	struct videomode vm;
+
+	drm_display_mode_to_videomode(mode, &vm);
+
+	pm_runtime_get_sync(dcss->dev);
+
+	vm.pixelclock = mode->crtc_clock * 1000;
+
+	dcss_ss_subsam_set(dcss->ss);
+	dcss_dtg_css_set(dcss->dtg);
+
+	if (!drm_mode_equal(mode, old_mode) || !old_crtc_state->active) {
+		dcss_dtg_sync_set(dcss->dtg, &vm);
+		dcss_ss_sync_set(dcss->ss, &vm,
+				 mode->flags & DRM_MODE_FLAG_PHSYNC,
+				 mode->flags & DRM_MODE_FLAG_PVSYNC);
+	}
+
+	dcss_enable_dtg_and_ss(dcss);
+
+	dcss_ctxld_enable(dcss->ctxld);
+
+	/* Allow CTXLD kick interrupt to be disabled when VBLANK is disabled. */
+	dcss_crtc->disable_ctxld_kick_irq = true;
+}
+
+static void dcss_crtc_atomic_disable(struct drm_crtc *crtc,
+				     struct drm_crtc_state *old_crtc_state)
+{
+	struct dcss_crtc *dcss_crtc = container_of(crtc, struct dcss_crtc,
+						   base);
+	struct dcss_dev *dcss = dcss_crtc->base.dev->dev_private;
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+	struct drm_display_mode *old_mode = &old_crtc_state->adjusted_mode;
+
+	drm_atomic_helper_disable_planes_on_crtc(old_crtc_state, false);
+
+	spin_lock_irq(&crtc->dev->event_lock);
+	if (crtc->state->event) {
+		drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		crtc->state->event = NULL;
+	}
+	spin_unlock_irq(&crtc->dev->event_lock);
+
+	dcss_dtg_ctxld_kick_irq_enable(dcss->dtg, true);
+
+	reinit_completion(&dcss->disable_completion);
+
+	dcss_disable_dtg_and_ss(dcss);
+
+	dcss_ctxld_enable(dcss->ctxld);
+
+	if (!drm_mode_equal(mode, old_mode) || !crtc->state->active)
+		if (!wait_for_completion_timeout(&dcss->disable_completion,
+						 msecs_to_jiffies(100)))
+			dev_err(dcss->dev, "Shutting off DTG timed out.\n");
+
+	/*
+	 * Do not shut off CTXLD kick interrupt when shutting VBLANK off. It
+	 * will be needed to commit the last changes, before going to suspend.
+	 */
+	dcss_crtc->disable_ctxld_kick_irq = false;
+
+	drm_crtc_vblank_off(crtc);
+
+	pm_runtime_mark_last_busy(dcss->dev);
+	pm_runtime_put_autosuspend(dcss->dev);
+}
+
+static const struct drm_crtc_helper_funcs dcss_helper_funcs = {
+	.atomic_begin = dcss_crtc_atomic_begin,
+	.atomic_flush = dcss_crtc_atomic_flush,
+	.atomic_enable = dcss_crtc_atomic_enable,
+	.atomic_disable = dcss_crtc_atomic_disable,
+};
+
+static irqreturn_t dcss_crtc_irq_handler(int irq, void *dev_id)
+{
+	struct dcss_crtc *dcss_crtc = dev_id;
+	struct dcss_dev *dcss = dcss_crtc->base.dev->dev_private;
+
+	if (!dcss_dtg_vblank_irq_valid(dcss->dtg))
+		return IRQ_NONE;
+
+	if (dcss_ctxld_is_flushed(dcss->ctxld))
+		drm_crtc_handle_vblank(&dcss_crtc->base);
+
+	dcss_dtg_vblank_irq_clear(dcss->dtg);
+
+	return IRQ_HANDLED;
+}
+
+int dcss_crtc_init(struct dcss_crtc *crtc, struct drm_device *drm)
+{
+	struct dcss_dev *dcss = drm->dev_private;
+	struct platform_device *pdev = to_platform_device(dcss->dev);
+	int ret;
+
+	crtc->plane[0] = dcss_plane_init(drm, drm_crtc_mask(&crtc->base),
+					 DRM_PLANE_TYPE_PRIMARY, 0);
+	if (IS_ERR(crtc->plane[0]))
+		return PTR_ERR(crtc->plane[0]);
+
+	crtc->base.port = dcss->of_port;
+
+	drm_crtc_helper_add(&crtc->base, &dcss_helper_funcs);
+	ret = drm_crtc_init_with_planes(drm, &crtc->base, &crtc->plane[0]->base,
+					NULL, &dcss_crtc_funcs, NULL);
+	if (ret) {
+		dev_err(dcss->dev, "failed to init crtc\n");
+		return ret;
+	}
+
+	crtc->irq = platform_get_irq_byname(pdev, "vblank");
+	if (crtc->irq < 0)
+		return crtc->irq;
+
+	ret = request_irq(crtc->irq, dcss_crtc_irq_handler,
+			  0, "dcss_drm", crtc);
+	if (ret) {
+		dev_err(dcss->dev, "irq request failed with %d.\n", ret);
+		return ret;
+	}
+
+	disable_irq(crtc->irq);
+
+	return 0;
+}
+
+void dcss_crtc_deinit(struct dcss_crtc *crtc, struct drm_device *drm)
+{
+	free_irq(crtc->irq, crtc);
+}

drivers/gpu/drm/imx/dcss/dcss-dev.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/clk.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <drm/drm_modeset_helper.h>
+
+#include "dcss-dev.h"
+
+static void dcss_clocks_enable(struct dcss_dev *dcss)
+{
+	clk_prepare_enable(dcss->axi_clk);
+	clk_prepare_enable(dcss->apb_clk);
+	clk_prepare_enable(dcss->rtrm_clk);
+	clk_prepare_enable(dcss->dtrc_clk);
+	clk_prepare_enable(dcss->pix_clk);
+}
+
+static void dcss_clocks_disable(struct dcss_dev *dcss)
+{
+	clk_disable_unprepare(dcss->pix_clk);
+	clk_disable_unprepare(dcss->dtrc_clk);
+	clk_disable_unprepare(dcss->rtrm_clk);
+	clk_disable_unprepare(dcss->apb_clk);
+	clk_disable_unprepare(dcss->axi_clk);
+}
+
+static void dcss_disable_dtg_and_ss_cb(void *data)
+{
+	struct dcss_dev *dcss = data;
+
+	dcss->disable_callback = NULL;
+
+	dcss_ss_shutoff(dcss->ss);
+	dcss_dtg_shutoff(dcss->dtg);
+
+	complete(&dcss->disable_completion);
+}
+
+void dcss_disable_dtg_and_ss(struct dcss_dev *dcss)
+{
+	dcss->disable_callback = dcss_disable_dtg_and_ss_cb;
+}
+
+void dcss_enable_dtg_and_ss(struct dcss_dev *dcss)
+{
+	if (dcss->disable_callback)
+		dcss->disable_callback = NULL;
+
+	dcss_dtg_enable(dcss->dtg);
+	dcss_ss_enable(dcss->ss);
+}
+
+static int dcss_submodules_init(struct dcss_dev *dcss)
+{
+	int ret = 0;
+	u32 base_addr = dcss->start_addr;
+	const struct dcss_type_data *devtype = dcss->devtype;
+
+	dcss_clocks_enable(dcss);
+
+	ret = dcss_blkctl_init(dcss, base_addr + devtype->blkctl_ofs);
+	if (ret)
+		return ret;
+
+	ret = dcss_ctxld_init(dcss, base_addr + devtype->ctxld_ofs);
+	if (ret)
+		goto ctxld_err;
+
+	ret = dcss_dtg_init(dcss, base_addr + devtype->dtg_ofs);
+	if (ret)
+		goto dtg_err;
+
+	ret = dcss_ss_init(dcss, base_addr + devtype->ss_ofs);
+	if (ret)
+		goto ss_err;
+
+	ret = dcss_dpr_init(dcss, base_addr + devtype->dpr_ofs);
+	if (ret)
+		goto dpr_err;
+
+	ret = dcss_scaler_init(dcss, base_addr + devtype->scaler_ofs);
+	if (ret)
+		goto scaler_err;
+
+	dcss_clocks_disable(dcss);
+
+	return 0;
+
+scaler_err:
+	dcss_dpr_exit(dcss->dpr);
+
+dpr_err:
+	dcss_ss_exit(dcss->ss);
+
+ss_err:
+	dcss_dtg_exit(dcss->dtg);
+
+dtg_err:
+	dcss_ctxld_exit(dcss->ctxld);
+
+ctxld_err:
+	dcss_blkctl_exit(dcss->blkctl);
+
+	dcss_clocks_disable(dcss);
+
+	return ret;
+}
+
+static void dcss_submodules_stop(struct dcss_dev *dcss)
+{
+	dcss_clocks_enable(dcss);
+	dcss_scaler_exit(dcss->scaler);
+	dcss_dpr_exit(dcss->dpr);
+	dcss_ss_exit(dcss->ss);
+	dcss_dtg_exit(dcss->dtg);
+	dcss_ctxld_exit(dcss->ctxld);
+	dcss_blkctl_exit(dcss->blkctl);
+	dcss_clocks_disable(dcss);
+}
+
+static int dcss_clks_init(struct dcss_dev *dcss)
+{
+	int i;
+	struct {
+		const char *id;
+		struct clk **clk;
+	} clks[] = {
+		{"apb",   &dcss->apb_clk},
+		{"axi",   &dcss->axi_clk},
+		{"pix",   &dcss->pix_clk},
+		{"rtrm",  &dcss->rtrm_clk},
+		{"dtrc",  &dcss->dtrc_clk},
+	};
+
+	for (i = 0; i < ARRAY_SIZE(clks); i++) {
+		*clks[i].clk = devm_clk_get(dcss->dev, clks[i].id);
+		if (IS_ERR(*clks[i].clk)) {
+			dev_err(dcss->dev, "failed to get %s clock\n",
+				clks[i].id);
+			return PTR_ERR(*clks[i].clk);
+		}
+	}
+
+	return 0;
+}
+
+static void dcss_clks_release(struct dcss_dev *dcss)
+{
+	devm_clk_put(dcss->dev, dcss->dtrc_clk);
+	devm_clk_put(dcss->dev, dcss->rtrm_clk);
+	devm_clk_put(dcss->dev, dcss->pix_clk);
+	devm_clk_put(dcss->dev, dcss->axi_clk);
+	devm_clk_put(dcss->dev, dcss->apb_clk);
+}
+
+struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	int ret;
+	struct resource *res;
+	struct dcss_dev *dcss;
+	const struct dcss_type_data *devtype;
+
+	devtype = of_device_get_match_data(dev);
+	if (!devtype) {
+		dev_err(dev, "no device match found\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "cannot get memory resource\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	dcss = kzalloc(sizeof(*dcss), GFP_KERNEL);
+	if (!dcss)
+		return ERR_PTR(-ENOMEM);
+
+	dcss->dev = dev;
+	dcss->devtype = devtype;
+	dcss->hdmi_output = hdmi_output;
+
+	ret = dcss_clks_init(dcss);
+	if (ret) {
+		dev_err(dev, "clocks initialization failed\n");
+		goto err;
+	}
+
+	dcss->of_port = of_graph_get_port_by_id(dev->of_node, 0);
+	if (!dcss->of_port) {
+		dev_err(dev, "no port@0 node in %s\n", dev->of_node->full_name);
+		ret = -ENODEV;
+		goto clks_err;
+	}
+
+	dcss->start_addr = res->start;
+
+	ret = dcss_submodules_init(dcss);
+	if (ret) {
+		dev_err(dev, "submodules initialization failed\n");
+		goto clks_err;
+	}
+
+	init_completion(&dcss->disable_completion);
+
+	pm_runtime_set_autosuspend_delay(dev, 100);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_set_suspended(dev);
+	pm_runtime_allow(dev);
+	pm_runtime_enable(dev);
+
+	return dcss;
+
+clks_err:
+	dcss_clks_release(dcss);
+
+err:
+	kfree(dcss);
+
+	return ERR_PTR(ret);
+}
+
+void dcss_dev_destroy(struct dcss_dev *dcss)
+{
+	if (!pm_runtime_suspended(dcss->dev)) {
+		dcss_ctxld_suspend(dcss->ctxld);
+		dcss_clocks_disable(dcss);
+	}
+
+	pm_runtime_disable(dcss->dev);
+
+	dcss_submodules_stop(dcss);
+
+	dcss_clks_release(dcss);
+
+	kfree(dcss);
+}
+
+#ifdef CONFIG_PM_SLEEP
+int dcss_dev_suspend(struct device *dev)
+{
+	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
+	int ret;
+
+	drm_mode_config_helper_suspend(dcss_drv_dev_to_drm(dev));
+
+	if (pm_runtime_suspended(dev))
+		return 0;
+
+	ret = dcss_ctxld_suspend(dcss->ctxld);
+	if (ret)
+		return ret;
+
+	dcss_clocks_disable(dcss);
+
+	return 0;
+}
+
+int dcss_dev_resume(struct device *dev)
+{
+	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
+
+	if (pm_runtime_suspended(dev)) {
+		drm_mode_config_helper_resume(dcss_drv_dev_to_drm(dev));
+		return 0;
+	}
+
+	dcss_clocks_enable(dcss);
+
+	dcss_blkctl_cfg(dcss->blkctl);
+
+	dcss_ctxld_resume(dcss->ctxld);
+
+	drm_mode_config_helper_resume(dcss_drv_dev_to_drm(dev));
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+int dcss_dev_runtime_suspend(struct device *dev)
+{
+	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
+	int ret;
+
+	ret = dcss_ctxld_suspend(dcss->ctxld);
+	if (ret)
+		return ret;
+
+	dcss_clocks_disable(dcss);
+
+	return 0;
+}
+
+int dcss_dev_runtime_resume(struct device *dev)
+{
+	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
+
+	dcss_clocks_enable(dcss);
+
+	dcss_blkctl_cfg(dcss->blkctl);
+
+	dcss_ctxld_resume(dcss->ctxld);
+
+	return 0;
+}
+#endif /* CONFIG_PM */

drivers/gpu/drm/imx/dcss/dcss-dev.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2019 NXP.
+ */
+
+#ifndef __DCSS_PRV_H__
+#define __DCSS_PRV_H__
+
+#include <drm/drm_fourcc.h>
+#include <linux/io.h>
+#include <video/videomode.h>
+
+#define SET			0x04
+#define CLR			0x08
+#define TGL			0x0C
+
+#define dcss_writel(v, c)	writel((v), (c))
+#define dcss_readl(c)		readl(c)
+#define dcss_set(v, c)		writel((v), (c) + SET)
+#define dcss_clr(v, c)		writel((v), (c) + CLR)
+#define dcss_toggle(v, c)	writel((v), (c) + TGL)
+
+static inline void dcss_update(u32 v, u32 m, void __iomem *c)
+{
+	writel((readl(c) & ~(m)) | (v), (c));
+}
+
+#define DCSS_DBG_REG(reg)	{.name = #reg, .ofs = reg}
+
+enum {
+	DCSS_IMX8MQ = 0,
+};
+
+struct dcss_type_data {
+	const char *name;
+	u32 blkctl_ofs;
+	u32 ctxld_ofs;
+	u32 rdsrc_ofs;
+	u32 wrscl_ofs;
+	u32 dtg_ofs;
+	u32 scaler_ofs;
+	u32 ss_ofs;
+	u32 dpr_ofs;
+	u32 dtrc_ofs;
+	u32 dec400d_ofs;
+	u32 hdr10_ofs;
+};
+
+struct dcss_debug_reg {
+	char *name;
+	u32 ofs;
+};
+
+enum dcss_ctxld_ctx_type {
+	CTX_DB,
+	CTX_SB_HP, /* high-priority */
+	CTX_SB_LP, /* low-priority  */
+};
+
+struct dcss_dev {
+	struct device *dev;
+	const struct dcss_type_data *devtype;
+	struct device_node *of_port;
+
+	u32 start_addr;
+
+	struct dcss_blkctl *blkctl;
+	struct dcss_ctxld *ctxld;
+	struct dcss_dpr *dpr;
+	struct dcss_dtg *dtg;
+	struct dcss_ss *ss;
+	struct dcss_hdr10 *hdr10;
+	struct dcss_scaler *scaler;
+	struct dcss_dtrc *dtrc;
+	struct dcss_dec400d *dec400d;
+	struct dcss_wrscl *wrscl;
+	struct dcss_rdsrc *rdsrc;
+
+	struct clk *apb_clk;
+	struct clk *axi_clk;
+	struct clk *pix_clk;
+	struct clk *rtrm_clk;
+	struct clk *dtrc_clk;
+	struct clk *pll_src_clk;
+	struct clk *pll_phy_ref_clk;
+
+	bool hdmi_output;
+
+	void (*disable_callback)(void *data);
+	struct completion disable_completion;
+};
+
+struct dcss_dev *dcss_drv_dev_to_dcss(struct device *dev);
+struct drm_device *dcss_drv_dev_to_drm(struct device *dev);
+struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output);
+void dcss_dev_destroy(struct dcss_dev *dcss);
+int dcss_dev_runtime_suspend(struct device *dev);
+int dcss_dev_runtime_resume(struct device *dev);
+int dcss_dev_suspend(struct device *dev);
+int dcss_dev_resume(struct device *dev);
+void dcss_enable_dtg_and_ss(struct dcss_dev *dcss);
+void dcss_disable_dtg_and_ss(struct dcss_dev *dcss);
+
+/* BLKCTL */
+int dcss_blkctl_init(struct dcss_dev *dcss, unsigned long blkctl_base);
+void dcss_blkctl_cfg(struct dcss_blkctl *blkctl);
+void dcss_blkctl_exit(struct dcss_blkctl *blkctl);
+
+/* CTXLD */
+int dcss_ctxld_init(struct dcss_dev *dcss, unsigned long ctxld_base);
+void dcss_ctxld_exit(struct dcss_ctxld *ctxld);
+void dcss_ctxld_write(struct dcss_ctxld *ctxld, u32 ctx_id,
+		      u32 val, u32 reg_idx);
+int dcss_ctxld_resume(struct dcss_ctxld *dcss_ctxld);
+int dcss_ctxld_suspend(struct dcss_ctxld *dcss_ctxld);
+void dcss_ctxld_write_irqsafe(struct dcss_ctxld *ctlxd, u32 ctx_id, u32 val,
+			      u32 reg_ofs);
+void dcss_ctxld_kick(struct dcss_ctxld *ctxld);
+bool dcss_ctxld_is_flushed(struct dcss_ctxld *ctxld);
+int dcss_ctxld_enable(struct dcss_ctxld *ctxld);
+void dcss_ctxld_register_completion(struct dcss_ctxld *ctxld,
+				    struct completion *dis_completion);
+void dcss_ctxld_assert_locked(struct dcss_ctxld *ctxld);
+
+/* DPR */
+int dcss_dpr_init(struct dcss_dev *dcss, unsigned long dpr_base);
+void dcss_dpr_exit(struct dcss_dpr *dpr);
+void dcss_dpr_write_sysctrl(struct dcss_dpr *dpr);
+void dcss_dpr_set_res(struct dcss_dpr *dpr, int ch_num, u32 xres, u32 yres);
+void dcss_dpr_addr_set(struct dcss_dpr *dpr, int ch_num, u32 luma_base_addr,
+		       u32 chroma_base_addr, u16 pitch);
+void dcss_dpr_enable(struct dcss_dpr *dpr, int ch_num, bool en);
+void dcss_dpr_format_set(struct dcss_dpr *dpr, int ch_num,
+			 const struct drm_format_info *format, u64 modifier);
+void dcss_dpr_set_rotation(struct dcss_dpr *dpr, int ch_num, u32 rotation);
+
+/* DTG */
+int dcss_dtg_init(struct dcss_dev *dcss, unsigned long dtg_base);
+void dcss_dtg_exit(struct dcss_dtg *dtg);
+bool dcss_dtg_vblank_irq_valid(struct dcss_dtg *dtg);
+void dcss_dtg_vblank_irq_enable(struct dcss_dtg *dtg, bool en);
+void dcss_dtg_vblank_irq_clear(struct dcss_dtg *dtg);
+void dcss_dtg_sync_set(struct dcss_dtg *dtg, struct videomode *vm);
+void dcss_dtg_css_set(struct dcss_dtg *dtg);
+void dcss_dtg_enable(struct dcss_dtg *dtg);
+void dcss_dtg_shutoff(struct dcss_dtg *dtg);
+bool dcss_dtg_is_enabled(struct dcss_dtg *dtg);
+void dcss_dtg_ctxld_kick_irq_enable(struct dcss_dtg *dtg, bool en);
+bool dcss_dtg_global_alpha_changed(struct dcss_dtg *dtg, int ch_num, int alpha);
+void dcss_dtg_plane_alpha_set(struct dcss_dtg *dtg, int ch_num,
+			      const struct drm_format_info *format, int alpha);
+void dcss_dtg_plane_pos_set(struct dcss_dtg *dtg, int ch_num,
+			    int px, int py, int pw, int ph);
+void dcss_dtg_ch_enable(struct dcss_dtg *dtg, int ch_num, bool en);
+
+/* SUBSAM */
+int dcss_ss_init(struct dcss_dev *dcss, unsigned long subsam_base);
+void dcss_ss_exit(struct dcss_ss *ss);
+void dcss_ss_enable(struct dcss_ss *ss);
+void dcss_ss_shutoff(struct dcss_ss *ss);
+void dcss_ss_subsam_set(struct dcss_ss *ss);
+void dcss_ss_sync_set(struct dcss_ss *ss, struct videomode *vm,
+		      bool phsync, bool pvsync);
+
+/* SCALER */
+int dcss_scaler_init(struct dcss_dev *dcss, unsigned long scaler_base);
+void dcss_scaler_exit(struct dcss_scaler *scl);
+void dcss_scaler_setup(struct dcss_scaler *scl, int ch_num,
+		       const struct drm_format_info *format,
+		       int src_xres, int src_yres, int dst_xres, int dst_yres,
+		       u32 vrefresh_hz);
+void dcss_scaler_ch_enable(struct dcss_scaler *scl, int ch_num, bool en);
+int dcss_scaler_get_min_max_ratios(struct dcss_scaler *scl, int ch_num,
+				   int *min, int *max);
+void dcss_scaler_write_sclctrl(struct dcss_scaler *scl);
+
+#endif /* __DCSS_PRV_H__ */

drivers/gpu/drm/imx/dcss/dcss-drv.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <drm/drm_of.h>
+
+#include "dcss-dev.h"
+#include "dcss-kms.h"
+
+struct dcss_drv {
+	struct dcss_dev *dcss;
+	struct dcss_kms_dev *kms;
+};
+
+struct dcss_dev *dcss_drv_dev_to_dcss(struct device *dev)
+{
+	struct dcss_drv *mdrv = dev_get_drvdata(dev);
+
+	return mdrv ? mdrv->dcss : NULL;
+}
+
+struct drm_device *dcss_drv_dev_to_drm(struct device *dev)
+{
+	struct dcss_drv *mdrv = dev_get_drvdata(dev);
+
+	return mdrv ? &mdrv->kms->base : NULL;
+}
+
+static int dcss_drv_platform_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *remote;
+	struct dcss_drv *mdrv;
+	int err = 0;
+	bool hdmi_output = true;
+
+	if (!dev->of_node)
+		return -ENODEV;
+
+	remote = of_graph_get_remote_node(dev->of_node, 0, 0);
+	if (!remote)
+		return -ENODEV;
+
+	hdmi_output = !of_device_is_compatible(remote, "fsl,imx8mq-nwl-dsi");
+
+	of_node_put(remote);
+
+	mdrv = kzalloc(sizeof(*mdrv), GFP_KERNEL);
+	if (!mdrv)
+		return -ENOMEM;
+
+	mdrv->dcss = dcss_dev_create(dev, hdmi_output);
+	if (IS_ERR(mdrv->dcss)) {
+		err = PTR_ERR(mdrv->dcss);
+		goto err;
+	}
+
+	dev_set_drvdata(dev, mdrv);
+
+	mdrv->kms = dcss_kms_attach(mdrv->dcss);
+	if (IS_ERR(mdrv->kms)) {
+		err = PTR_ERR(mdrv->kms);
+		goto dcss_shutoff;
+	}
+
+	return 0;
+
+dcss_shutoff:
+	dcss_dev_destroy(mdrv->dcss);
+
+	dev_set_drvdata(dev, NULL);
+
+err:
+	kfree(mdrv);
+	return err;
+}
+
+static int dcss_drv_platform_remove(struct platform_device *pdev)
+{
+	struct dcss_drv *mdrv = dev_get_drvdata(&pdev->dev);
+
+	if (!mdrv)
+		return 0;
+
+	dcss_kms_detach(mdrv->kms);
+	dcss_dev_destroy(mdrv->dcss);
+
+	dev_set_drvdata(&pdev->dev, NULL);
+
+	kfree(mdrv);
+
+	return 0;
+}
+
+static struct dcss_type_data dcss_types[] = {
+	[DCSS_IMX8MQ] = {
+		.name = "DCSS_IMX8MQ",
+		.blkctl_ofs = 0x2F000,
+		.ctxld_ofs = 0x23000,
+		.dtg_ofs = 0x20000,
+		.scaler_ofs = 0x1C000,
+		.ss_ofs = 0x1B000,
+		.dpr_ofs = 0x18000,
+	},
+};
+
+static const struct of_device_id dcss_of_match[] = {
+	{ .compatible = "nxp,imx8mq-dcss", .data = &dcss_types[DCSS_IMX8MQ], },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, dcss_of_match);
+
+static const struct dev_pm_ops dcss_dev_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(dcss_dev_suspend, dcss_dev_resume)
+	SET_RUNTIME_PM_OPS(dcss_dev_runtime_suspend,
+			   dcss_dev_runtime_resume, NULL)
+};
+
+static struct platform_driver dcss_platform_driver = {
+	.probe	= dcss_drv_platform_probe,
+	.remove	= dcss_drv_platform_remove,
+	.driver	= {
+		.name = "imx-dcss",
+		.of_match_table	= dcss_of_match,
+		.pm = &dcss_dev_pm,
+	},
+};
+
+module_platform_driver(dcss_platform_driver);
+
+MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@nxp.com>");
+MODULE_DESCRIPTION("DCSS driver for i.MX8MQ");
+MODULE_LICENSE("GPL v2");

drivers/gpu/drm/imx/dcss/dcss-kms.c

+// 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;
+}

drivers/gpu/drm/imx/dcss/dcss-kms.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2019 NXP.
+ */
+
+#ifndef _DCSS_KMS_H_
+#define _DCSS_KMS_H_
+
+#include <drm/drm_encoder.h>
+
+struct dcss_plane {
+	struct drm_plane base;
+
+	int ch_num;
+};
+
+struct dcss_crtc {
+	struct drm_crtc		base;
+	struct drm_crtc_state	*state;
+
+	struct dcss_plane	*plane[3];
+
+	int			irq;
+
+	bool disable_ctxld_kick_irq;
+};
+
+struct dcss_kms_dev {
+	struct drm_device base;
+	struct dcss_crtc crtc;
+	struct drm_encoder encoder;
+};
+
+struct dcss_kms_dev *dcss_kms_attach(struct dcss_dev *dcss);
+void dcss_kms_detach(struct dcss_kms_dev *kms);
+int dcss_crtc_init(struct dcss_crtc *crtc, struct drm_device *drm);
+void dcss_crtc_deinit(struct dcss_crtc *crtc, struct drm_device *drm);
+struct dcss_plane *dcss_plane_init(struct drm_device *drm,
+				   unsigned int possible_crtcs,
+				   enum drm_plane_type type,
+				   unsigned int zpos);
+
+#endif

drivers/gpu/drm/imx/dcss/dcss-ss.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+
+#include "dcss-dev.h"
+
+#define DCSS_SS_SYS_CTRL			0x00
+#define   RUN_EN				BIT(0)
+#define DCSS_SS_DISPLAY				0x10
+#define   LRC_X_POS				0
+#define   LRC_X_MASK				GENMASK(12, 0)
+#define   LRC_Y_POS				16
+#define   LRC_Y_MASK				GENMASK(28, 16)
+#define DCSS_SS_HSYNC				0x20
+#define DCSS_SS_VSYNC				0x30
+#define   SYNC_START_POS			0
+#define   SYNC_START_MASK			GENMASK(12, 0)
+#define   SYNC_END_POS				16
+#define   SYNC_END_MASK				GENMASK(28, 16)
+#define   SYNC_POL				BIT(31)
+#define DCSS_SS_DE_ULC				0x40
+#define   ULC_X_POS				0
+#define   ULC_X_MASK				GENMASK(12, 0)
+#define   ULC_Y_POS				16
+#define   ULC_Y_MASK				GENMASK(28, 16)
+#define   ULC_POL				BIT(31)
+#define DCSS_SS_DE_LRC				0x50
+#define DCSS_SS_MODE				0x60
+#define   PIPE_MODE_POS				0
+#define   PIPE_MODE_MASK			GENMASK(1, 0)
+#define DCSS_SS_COEFF				0x70
+#define   HORIZ_A_POS				0
+#define   HORIZ_A_MASK				GENMASK(3, 0)
+#define   HORIZ_B_POS				4
+#define   HORIZ_B_MASK				GENMASK(7, 4)
+#define   HORIZ_C_POS				8
+#define   HORIZ_C_MASK				GENMASK(11, 8)
+#define   HORIZ_H_NORM_POS			12
+#define   HORIZ_H_NORM_MASK			GENMASK(14, 12)
+#define   VERT_A_POS				16
+#define   VERT_A_MASK				GENMASK(19, 16)
+#define   VERT_B_POS				20
+#define   VERT_B_MASK				GENMASK(23, 20)
+#define   VERT_C_POS				24
+#define   VERT_C_MASK				GENMASK(27, 24)
+#define   VERT_H_NORM_POS			28
+#define   VERT_H_NORM_MASK			GENMASK(30, 28)
+#define DCSS_SS_CLIP_CB				0x80
+#define DCSS_SS_CLIP_CR				0x90
+#define   CLIP_MIN_POS				0
+#define   CLIP_MIN_MASK				GENMASK(9, 0)
+#define   CLIP_MAX_POS				0
+#define   CLIP_MAX_MASK				GENMASK(23, 16)
+#define DCSS_SS_INTER_MODE			0xA0
+#define   INT_EN				BIT(0)
+#define   VSYNC_SHIFT				BIT(1)
+
+struct dcss_ss {
+	struct device *dev;
+	void __iomem *base_reg;
+	u32 base_ofs;
+
+	struct dcss_ctxld *ctxld;
+	u32 ctx_id;
+
+	bool in_use;
+};
+
+static void dcss_ss_write(struct dcss_ss *ss, u32 val, u32 ofs)
+{
+	if (!ss->in_use)
+		dcss_writel(val, ss->base_reg + ofs);
+
+	dcss_ctxld_write(ss->ctxld, ss->ctx_id, val,
+			 ss->base_ofs + ofs);
+}
+
+int dcss_ss_init(struct dcss_dev *dcss, unsigned long ss_base)
+{
+	struct dcss_ss *ss;
+
+	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
+	if (!ss)
+		return -ENOMEM;
+
+	dcss->ss = ss;
+	ss->dev = dcss->dev;
+	ss->ctxld = dcss->ctxld;
+
+	ss->base_reg = ioremap(ss_base, SZ_4K);
+	if (!ss->base_reg) {
+		dev_err(dcss->dev, "ss: unable to remap ss base\n");
+		kfree(ss);
+		return -ENOMEM;
+	}
+
+	ss->base_ofs = ss_base;
+	ss->ctx_id = CTX_SB_HP;
+
+	return 0;
+}
+
+void dcss_ss_exit(struct dcss_ss *ss)
+{
+	/* stop SS */
+	dcss_writel(0, ss->base_reg + DCSS_SS_SYS_CTRL);
+
+	if (ss->base_reg)
+		iounmap(ss->base_reg);
+
+	kfree(ss);
+}
+
+void dcss_ss_subsam_set(struct dcss_ss *ss)
+{
+	dcss_ss_write(ss, 0x41614161, DCSS_SS_COEFF);
+	dcss_ss_write(ss, 0, DCSS_SS_MODE);
+	dcss_ss_write(ss, 0x03ff0000, DCSS_SS_CLIP_CB);
+	dcss_ss_write(ss, 0x03ff0000, DCSS_SS_CLIP_CR);
+}
+
+void dcss_ss_sync_set(struct dcss_ss *ss, struct videomode *vm,
+		      bool phsync, bool pvsync)
+{
+	u16 lrc_x, lrc_y;
+	u16 hsync_start, hsync_end;
+	u16 vsync_start, vsync_end;
+	u16 de_ulc_x, de_ulc_y;
+	u16 de_lrc_x, de_lrc_y;
+
+	lrc_x = vm->hfront_porch + vm->hback_porch + vm->hsync_len +
+		vm->hactive - 1;
+	lrc_y = vm->vfront_porch + vm->vback_porch + vm->vsync_len +
+		vm->vactive - 1;
+
+	dcss_ss_write(ss, (lrc_y << LRC_Y_POS) | lrc_x, DCSS_SS_DISPLAY);
+
+	hsync_start = vm->hfront_porch + vm->hback_porch + vm->hsync_len +
+		      vm->hactive - 1;
+	hsync_end = vm->hsync_len - 1;
+
+	dcss_ss_write(ss, (phsync ? SYNC_POL : 0) |
+		      ((u32)hsync_end << SYNC_END_POS) | hsync_start,
+		      DCSS_SS_HSYNC);
+
+	vsync_start = vm->vfront_porch - 1;
+	vsync_end = vm->vfront_porch + vm->vsync_len - 1;
+
+	dcss_ss_write(ss, (pvsync ? SYNC_POL : 0) |
+		      ((u32)vsync_end << SYNC_END_POS) | vsync_start,
+		      DCSS_SS_VSYNC);
+
+	de_ulc_x = vm->hsync_len + vm->hback_porch - 1;
+	de_ulc_y = vm->vsync_len + vm->vfront_porch + vm->vback_porch;
+
+	dcss_ss_write(ss, SYNC_POL | ((u32)de_ulc_y << ULC_Y_POS) | de_ulc_x,
+		      DCSS_SS_DE_ULC);
+
+	de_lrc_x = vm->hsync_len + vm->hback_porch + vm->hactive - 1;
+	de_lrc_y = vm->vsync_len + vm->vfront_porch + vm->vback_porch +
+		   vm->vactive - 1;
+
+	dcss_ss_write(ss, (de_lrc_y << LRC_Y_POS) | de_lrc_x, DCSS_SS_DE_LRC);
+}
+
+void dcss_ss_enable(struct dcss_ss *ss)
+{
+	dcss_ss_write(ss, RUN_EN, DCSS_SS_SYS_CTRL);
+	ss->in_use = true;
+}
+
+void dcss_ss_shutoff(struct dcss_ss *ss)
+{
+	dcss_writel(0, ss->base_reg + DCSS_SS_SYS_CTRL);
+	ss->in_use = false;
+}