drm: Add new driver for MXSFB controller

Add new driver for the MXSFB controller found in i.MX23/28/6SX .
The MXSFB controller is a simple framebuffer controller with one
parallel LCD output. Unlike the MXSFB fbdev driver that is used
on these systems now, this driver uses the DRM/KMS framework.
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>

MAINTAINERS

@@ -8319,6 +8319,12 @@ T:	git git://linuxtv.org/mkrufky/tuners.git
 S:	Maintained
 F:	drivers/media/tuners/mxl5007t.*
 
+MXSFB DRM DRIVER
+M:	Marek Vasut <marex@denx.de>
+S:	Supported
+F:	drivers/gpu/drm/mxsfb/
+F:	Documentation/devicetree/bindings/display/mxsfb-drm.txt
+
 MYRICOM MYRI-10G 10GbE DRIVER (MYRI10GE)
 M:	Hyong-Youb Kim <hykim@myri.com>
 L:	netdev@vger.kernel.org

drivers/gpu/drm/Kconfig

@@ -240,6 +240,8 @@ source "drivers/gpu/drm/mediatek/Kconfig"
 
 source "drivers/gpu/drm/zte/Kconfig"
 
+source "drivers/gpu/drm/mxsfb/Kconfig"
+
 # Keep legacy drivers last
 
 menuconfig DRM_LEGACY

drivers/gpu/drm/Makefile

@@ -89,3 +89,4 @@ obj-$(CONFIG_DRM_ETNAVIV) += etnaviv/
 obj-$(CONFIG_DRM_ARCPGU)+= arc/
 obj-y			+= hisilicon/
 obj-$(CONFIG_DRM_ZTE)	+= zte/
+obj-$(CONFIG_DRM_MXSFB)	+= mxsfb/

drivers/gpu/drm/mxsfb/Kconfig

+config DRM_MXS
+	bool
+	help
+	  Choose this option to select drivers for MXS FB devices
+
+config DRM_MXSFB
+	tristate "i.MX23/i.MX28/i.MX6SX MXSFB LCD controller"
+	depends on DRM && OF
+	depends on COMMON_CLK
+	select DRM_MXS
+	select DRM_KMS_HELPER
+	select DRM_KMS_FB_HELPER
+	select DRM_KMS_CMA_HELPER
+	help
+	  Choose this option if you have an i.MX23/i.MX28/i.MX6SX MXSFB
+	  LCD controller.
+
+	  If M is selected the module will be called mxsfb.

drivers/gpu/drm/mxsfb/Makefile

+mxsfb-y := mxsfb_drv.o mxsfb_crtc.o mxsfb_out.o
+obj-$(CONFIG_DRM_MXSFB)	+= mxsfb.o

drivers/gpu/drm/mxsfb/mxsfb_crtc.c

+/*
+ * Copyright (C) 2016 Marek Vasut <marex@denx.de>
+ *
+ * This code is based on drivers/video/fbdev/mxsfb.c :
+ * Copyright (C) 2010 Juergen Beisert, Pengutronix
+ * Copyright (C) 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/of_graph.h>
+#include <linux/platform_data/simplefb.h>
+#include <video/videomode.h>
+
+#include "mxsfb_drv.h"
+#include "mxsfb_regs.h"
+
+static u32 set_hsync_pulse_width(struct mxsfb_drm_private *mxsfb, u32 val)
+{
+	return (val & mxsfb->devdata->hs_wdth_mask) <<
+		mxsfb->devdata->hs_wdth_shift;
+}
+
+/* Setup the MXSFB registers for decoding the pixels out of the framebuffer */
+static int mxsfb_set_pixel_fmt(struct mxsfb_drm_private *mxsfb)
+{
+	struct drm_crtc *crtc = &mxsfb->pipe.crtc;
+	struct drm_device *drm = crtc->dev;
+	const u32 format = crtc->primary->state->fb->pixel_format;
+	u32 ctrl, ctrl1;
+
+	ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER;
+
+	/*
+	 * WARNING: The bus width, CTRL_SET_BUS_WIDTH(), is configured to
+	 * match the selected mode here. This differs from the original
+	 * MXSFB driver, which had the option to configure the bus width
+	 * to arbitrary value. This limitation should not pose an issue.
+	 */
+
+	/* CTRL1 contains IRQ config and status bits, preserve those. */
+	ctrl1 = readl(mxsfb->base + LCDC_CTRL1);
+	ctrl1 &= CTRL1_CUR_FRAME_DONE_IRQ_EN | CTRL1_CUR_FRAME_DONE_IRQ;
+
+	switch (format) {
+	case DRM_FORMAT_RGB565:
+		dev_dbg(drm->dev, "Setting up RGB565 mode\n");
+		ctrl |= CTRL_SET_BUS_WIDTH(STMLCDIF_16BIT);
+		ctrl |= CTRL_SET_WORD_LENGTH(0);
+		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0xf);
+		break;
+	case DRM_FORMAT_XRGB8888:
+		dev_dbg(drm->dev, "Setting up XRGB8888 mode\n");
+		ctrl |= CTRL_SET_BUS_WIDTH(STMLCDIF_24BIT);
+		ctrl |= CTRL_SET_WORD_LENGTH(3);
+		/* Do not use packed pixels = one pixel per word instead. */
+		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0x7);
+		break;
+	default:
+		dev_err(drm->dev, "Unhandled pixel format %08x\n", format);
+		return -EINVAL;
+	}
+
+	writel(ctrl1, mxsfb->base + LCDC_CTRL1);
+	writel(ctrl, mxsfb->base + LCDC_CTRL);
+
+	return 0;
+}
+
+static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
+{
+	u32 reg;
+
+	if (mxsfb->clk_disp_axi)
+		clk_prepare_enable(mxsfb->clk_disp_axi);
+	clk_prepare_enable(mxsfb->clk);
+	mxsfb_enable_axi_clk(mxsfb);
+
+	/* If it was disabled, re-enable the mode again */
+	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
+
+	/* Enable the SYNC signals first, then the DMA engine */
+	reg = readl(mxsfb->base + LCDC_VDCTRL4);
+	reg |= VDCTRL4_SYNC_SIGNALS_ON;
+	writel(reg, mxsfb->base + LCDC_VDCTRL4);
+
+	writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
+}
+
+static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
+{
+	u32 reg;
+
+	/*
+	 * Even if we disable the controller here, it will still continue
+	 * until its FIFOs are running out of data
+	 */
+	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_CLR);
+
+	readl_poll_timeout(mxsfb->base + LCDC_CTRL, reg, !(reg & CTRL_RUN),
+			   0, 1000);
+
+	reg = readl(mxsfb->base + LCDC_VDCTRL4);
+	reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
+	writel(reg, mxsfb->base + LCDC_VDCTRL4);
+
+	mxsfb_disable_axi_clk(mxsfb);
+
+	clk_disable_unprepare(mxsfb->clk);
+	if (mxsfb->clk_disp_axi)
+		clk_disable_unprepare(mxsfb->clk_disp_axi);
+}
+
+static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
+{
+	struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode;
+	const u32 bus_flags = mxsfb->connector.display_info.bus_flags;
+	u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
+	int err;
+
+	/*
+	 * It seems, you can't re-program the controller if it is still
+	 * running. This may lead to shifted pictures (FIFO issue?), so
+	 * first stop the controller and drain its FIFOs.
+	 */
+	mxsfb_enable_axi_clk(mxsfb);
+
+	/* Clear the FIFOs */
+	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
+
+	err = mxsfb_set_pixel_fmt(mxsfb);
+	if (err)
+		return;
+
+	clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
+
+	writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
+	       TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
+	       mxsfb->base + mxsfb->devdata->transfer_count);
+
+	vsync_pulse_len = m->crtc_vsync_end - m->crtc_vsync_start;
+
+	vdctrl0 = VDCTRL0_ENABLE_PRESENT |	/* Always in DOTCLOCK mode */
+		  VDCTRL0_VSYNC_PERIOD_UNIT |
+		  VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
+		  VDCTRL0_SET_VSYNC_PULSE_WIDTH(vsync_pulse_len);
+	if (m->flags & DRM_MODE_FLAG_PHSYNC)
+		vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
+	if (m->flags & DRM_MODE_FLAG_PVSYNC)
+		vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
+	if (bus_flags & DRM_BUS_FLAG_DE_HIGH)
+		vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
+	if (bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
+		vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;
+
+	writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);
+
+	/* Frame length in lines. */
+	writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);
+
+	/* Line length in units of clocks or pixels. */
+	hsync_pulse_len = m->crtc_hsync_end - m->crtc_hsync_start;
+	writel(set_hsync_pulse_width(mxsfb, hsync_pulse_len) |
+	       VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
+	       mxsfb->base + LCDC_VDCTRL2);
+
+	writel(SET_HOR_WAIT_CNT(m->crtc_hblank_end - m->crtc_hsync_end) |
+	       SET_VERT_WAIT_CNT(m->crtc_vblank_end - m->crtc_vsync_end),
+	       mxsfb->base + LCDC_VDCTRL3);
+
+	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
+	       mxsfb->base + LCDC_VDCTRL4);
+
+	mxsfb_disable_axi_clk(mxsfb);
+}
+
+void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb)
+{
+	mxsfb_crtc_mode_set_nofb(mxsfb);
+	mxsfb_enable_controller(mxsfb);
+}
+
+void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb)
+{
+	mxsfb_disable_controller(mxsfb);
+}
+
+void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb,
+			       struct drm_plane_state *state)
+{
+	struct drm_simple_display_pipe *pipe = &mxsfb->pipe;
+	struct drm_crtc *crtc = &pipe->crtc;
+	struct drm_framebuffer *fb = pipe->plane.state->fb;
+	struct drm_pending_vblank_event *event;
+	struct drm_gem_cma_object *gem;
+
+	if (!crtc)
+		return;
+
+	spin_lock_irq(&crtc->dev->event_lock);
+	event = crtc->state->event;
+	if (event) {
+		crtc->state->event = NULL;
+
+		if (drm_crtc_vblank_get(crtc) == 0) {
+			drm_crtc_arm_vblank_event(crtc, event);
+		} else {
+			drm_crtc_send_vblank_event(crtc, event);
+		}
+	}
+	spin_unlock_irq(&crtc->dev->event_lock);
+
+	if (!fb)
+		return;
+
+	gem = drm_fb_cma_get_gem_obj(fb, 0);
+
+	mxsfb_enable_axi_clk(mxsfb);
+	writel(gem->paddr, mxsfb->base + mxsfb->devdata->next_buf);
+	mxsfb_disable_axi_clk(mxsfb);
+}

drivers/gpu/drm/mxsfb/mxsfb_drv.c

+/*
+ * Copyright (C) 2016 Marek Vasut <marex@denx.de>
+ *
+ * This code is based on drivers/video/fbdev/mxsfb.c :
+ * Copyright (C) 2010 Juergen Beisert, Pengutronix
+ * Copyright (C) 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/list.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/pm_runtime.h>
+#include <linux/reservation.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#include "mxsfb_drv.h"
+#include "mxsfb_regs.h"
+
+enum mxsfb_devtype {
+	MXSFB_V3,
+	MXSFB_V4,
+};
+
+static const struct mxsfb_devdata mxsfb_devdata[] = {
+	[MXSFB_V3] = {
+		.transfer_count	= LCDC_V3_TRANSFER_COUNT,
+		.cur_buf	= LCDC_V3_CUR_BUF,
+		.next_buf	= LCDC_V3_NEXT_BUF,
+		.debug0		= LCDC_V3_DEBUG0,
+		.hs_wdth_mask	= 0xff,
+		.hs_wdth_shift	= 24,
+		.ipversion	= 3,
+	},
+	[MXSFB_V4] = {
+		.transfer_count	= LCDC_V4_TRANSFER_COUNT,
+		.cur_buf	= LCDC_V4_CUR_BUF,
+		.next_buf	= LCDC_V4_NEXT_BUF,
+		.debug0		= LCDC_V4_DEBUG0,
+		.hs_wdth_mask	= 0x3fff,
+		.hs_wdth_shift	= 18,
+		.ipversion	= 4,
+	},
+};
+
+static const uint32_t mxsfb_formats[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_RGB565
+};
+
+static struct mxsfb_drm_private *
+drm_pipe_to_mxsfb_drm_private(struct drm_simple_display_pipe *pipe)
+{
+	return container_of(pipe, struct mxsfb_drm_private, pipe);
+}
+
+void mxsfb_enable_axi_clk(struct mxsfb_drm_private *mxsfb)
+{
+	if (mxsfb->clk_axi)
+		clk_prepare_enable(mxsfb->clk_axi);
+}
+
+void mxsfb_disable_axi_clk(struct mxsfb_drm_private *mxsfb)
+{
+	if (mxsfb->clk_axi)
+		clk_disable_unprepare(mxsfb->clk_axi);
+}
+
+static const struct drm_mode_config_funcs mxsfb_mode_config_funcs = {
+	.fb_create		= drm_fb_cma_create,
+	.atomic_check		= drm_atomic_helper_check,
+	.atomic_commit		= drm_atomic_helper_commit,
+};
+
+static void mxsfb_pipe_enable(struct drm_simple_display_pipe *pipe,
+			      struct drm_crtc_state *crtc_state)
+{
+	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
+
+	mxsfb_crtc_enable(mxsfb);
+}
+
+static void mxsfb_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
+
+	mxsfb_crtc_disable(mxsfb);
+}
+
+static void mxsfb_pipe_update(struct drm_simple_display_pipe *pipe,
+			      struct drm_plane_state *plane_state)
+{
+	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
+
+	mxsfb_plane_atomic_update(mxsfb, plane_state);
+}
+
+static int mxsfb_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
+				 struct drm_plane_state *plane_state)
+{
+	return drm_fb_cma_prepare_fb(&pipe->plane, plane_state);
+}
+
+struct drm_simple_display_pipe_funcs mxsfb_funcs = {
+	.enable		= mxsfb_pipe_enable,
+	.disable	= mxsfb_pipe_disable,
+	.update		= mxsfb_pipe_update,
+	.prepare_fb	= mxsfb_pipe_prepare_fb,
+};
+
+static int mxsfb_load(struct drm_device *drm, unsigned long flags)
+{
+	struct platform_device *pdev = to_platform_device(drm->dev);
+	struct mxsfb_drm_private *mxsfb;
+	struct resource *res;
+	int ret;
+
+	mxsfb = devm_kzalloc(&pdev->dev, sizeof(*mxsfb), GFP_KERNEL);
+	if (!mxsfb)
+		return -ENOMEM;
+
+	drm->dev_private = mxsfb;
+	mxsfb->devdata = &mxsfb_devdata[pdev->id_entry->driver_data];
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mxsfb->base = devm_ioremap_resource(drm->dev, res);
+	if (IS_ERR(mxsfb->base))
+		return PTR_ERR(mxsfb->base);
+
+	mxsfb->clk = devm_clk_get(drm->dev, NULL);
+	if (IS_ERR(mxsfb->clk))
+		return PTR_ERR(mxsfb->clk);
+
+	mxsfb->clk_axi = devm_clk_get(drm->dev, "axi");
+	if (IS_ERR(mxsfb->clk_axi))
+		mxsfb->clk_axi = NULL;
+
+	mxsfb->clk_disp_axi = devm_clk_get(drm->dev, "disp_axi");
+	if (IS_ERR(mxsfb->clk_disp_axi))
+		mxsfb->clk_disp_axi = NULL;
+
+	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	pm_runtime_enable(drm->dev);
+
+	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to initialise vblank\n");
+		goto err_vblank;
+	}
+
+	/* Modeset init */
+	drm_mode_config_init(drm);
+
+	ret = mxsfb_create_output(drm);
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to create outputs\n");
+		goto err_vblank;
+	}
+
+	ret = drm_simple_display_pipe_init(drm, &mxsfb->pipe, &mxsfb_funcs,
+			mxsfb_formats, ARRAY_SIZE(mxsfb_formats),
+			&mxsfb->connector);
+	if (ret < 0) {
+		dev_err(drm->dev, "Cannot setup simple display pipe\n");
+		goto err_vblank;
+	}
+
+	ret = drm_panel_attach(mxsfb->panel, &mxsfb->connector);
+	if (ret) {
+		dev_err(drm->dev, "Cannot connect panel\n");
+		goto err_vblank;
+	}
+
+	drm->mode_config.min_width	= MXSFB_MIN_XRES;
+	drm->mode_config.min_height	= MXSFB_MIN_YRES;
+	drm->mode_config.max_width	= MXSFB_MAX_XRES;
+	drm->mode_config.max_height	= MXSFB_MAX_YRES;
+	drm->mode_config.funcs		= &mxsfb_mode_config_funcs;
+
+	drm_mode_config_reset(drm);
+
+	pm_runtime_get_sync(drm->dev);
+	ret = drm_irq_install(drm, platform_get_irq(pdev, 0));
+	pm_runtime_put_sync(drm->dev);
+
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to install IRQ handler\n");
+		goto err_irq;
+	}
+
+	drm_kms_helper_poll_init(drm);
+
+	mxsfb->fbdev = drm_fbdev_cma_init(drm, 32, drm->mode_config.num_crtc,
+					  drm->mode_config.num_connector);
+	if (IS_ERR(mxsfb->fbdev)) {
+		mxsfb->fbdev = NULL;
+		dev_err(drm->dev, "Failed to init FB CMA area\n");
+		goto err_cma;
+	}
+
+	platform_set_drvdata(pdev, drm);
+
+	drm_helper_hpd_irq_event(drm);
+
+	return 0;
+
+err_cma:
+	drm_irq_uninstall(drm);
+err_irq:
+	drm_panel_detach(mxsfb->panel);
+err_vblank:
+	pm_runtime_disable(drm->dev);
+
+	return ret;
+}
+
+static void mxsfb_unload(struct drm_device *drm)
+{
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+
+	if (mxsfb->fbdev)
+		drm_fbdev_cma_fini(mxsfb->fbdev);
+
+	drm_kms_helper_poll_fini(drm);
+	drm_mode_config_cleanup(drm);
+	drm_vblank_cleanup(drm);
+
+	pm_runtime_get_sync(drm->dev);
+	drm_irq_uninstall(drm);
+	pm_runtime_put_sync(drm->dev);
+
+	drm->dev_private = NULL;
+
+	pm_runtime_disable(drm->dev);
+}
+
+static void mxsfb_lastclose(struct drm_device *drm)
+{
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+
+	drm_fbdev_cma_restore_mode(mxsfb->fbdev);
+}
+
+static int mxsfb_enable_vblank(struct drm_device *drm, unsigned int crtc)
+{
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+
+	/* Clear and enable VBLANK IRQ */
+	mxsfb_enable_axi_clk(mxsfb);
+	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
+	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_SET);
+	mxsfb_disable_axi_clk(mxsfb);
+
+	return 0;
+}
+
+static void mxsfb_disable_vblank(struct drm_device *drm, unsigned int crtc)
+{
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+
+	/* Disable and clear VBLANK IRQ */
+	mxsfb_enable_axi_clk(mxsfb);
+	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR);
+	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
+	mxsfb_disable_axi_clk(mxsfb);
+}
+
+static void mxsfb_irq_preinstall(struct drm_device *drm)
+{
+	mxsfb_disable_vblank(drm, 0);
+}
+
+static irqreturn_t mxsfb_irq_handler(int irq, void *data)
+{
+	struct drm_device *drm = data;
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+	u32 reg;
+
+	mxsfb_enable_axi_clk(mxsfb);
+
+	reg = readl(mxsfb->base + LCDC_CTRL1);
+
+	if (reg & CTRL1_CUR_FRAME_DONE_IRQ)
+		drm_crtc_handle_vblank(&mxsfb->pipe.crtc);
+
+	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
+
+	mxsfb_disable_axi_clk(mxsfb);
+
+	return IRQ_HANDLED;
+}
+
+static const struct file_operations fops = {
+	.owner		= THIS_MODULE,
+	.open		= drm_open,
+	.release	= drm_release,
+	.unlocked_ioctl	= drm_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= drm_compat_ioctl,
+#endif
+	.poll		= drm_poll,
+	.read		= drm_read,
+	.llseek		= noop_llseek,
+	.mmap		= drm_gem_cma_mmap,
+};
+
+static struct drm_driver mxsfb_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET |
+				  DRIVER_PRIME | DRIVER_ATOMIC |
+				  DRIVER_HAVE_IRQ,
+	.lastclose		= mxsfb_lastclose,
+	.irq_handler		= mxsfb_irq_handler,
+	.irq_preinstall		= mxsfb_irq_preinstall,
+	.irq_uninstall		= mxsfb_irq_preinstall,
+	.get_vblank_counter	= drm_vblank_no_hw_counter,
+	.enable_vblank		= mxsfb_enable_vblank,
+	.disable_vblank		= mxsfb_disable_vblank,
+	.gem_free_object	= drm_gem_cma_free_object,
+	.gem_vm_ops		= &drm_gem_cma_vm_ops,
+	.dumb_create		= drm_gem_cma_dumb_create,
+	.dumb_map_offset	= drm_gem_cma_dumb_map_offset,
+	.dumb_destroy		= drm_gem_dumb_destroy,
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_export	= drm_gem_prime_export,
+	.gem_prime_import	= drm_gem_prime_import,
+	.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	= &fops,
+	.name	= "mxsfb-drm",
+	.desc	= "MXSFB Controller DRM",
+	.date	= "20160824",
+	.major	= 1,
+	.minor	= 0,
+};
+
+static const struct platform_device_id mxsfb_devtype[] = {
+	{ .name = "imx23-fb", .driver_data = MXSFB_V3, },
+	{ .name = "imx28-fb", .driver_data = MXSFB_V4, },
+	{ .name = "imx6sx-fb", .driver_data = MXSFB_V4, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, mxsfb_devtype);
+
+static const struct of_device_id mxsfb_dt_ids[] = {
+	{ .compatible = "fsl,imx23-lcdif", .data = &mxsfb_devtype[0], },
+	{ .compatible = "fsl,imx28-lcdif", .data = &mxsfb_devtype[1], },
+	{ .compatible = "fsl,imx6sx-lcdif", .data = &mxsfb_devtype[2], },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxsfb_dt_ids);
+
+static int mxsfb_probe(struct platform_device *pdev)
+{
+	struct drm_device *drm;
+	const struct of_device_id *of_id =
+			of_match_device(mxsfb_dt_ids, &pdev->dev);
+	int ret;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	if (of_id)
+		pdev->id_entry = of_id->data;
+
+	drm = drm_dev_alloc(&mxsfb_driver, &pdev->dev);
+	if (!drm)
+		return -ENOMEM;
+
+	ret = mxsfb_load(drm, 0);
+	if (ret)
+		goto err_free;
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto err_unload;
+
+	return 0;
+
+err_unload:
+	mxsfb_unload(drm);
+err_free:
+	drm_dev_unref(drm);
+
+	return ret;
+}
+
+static int mxsfb_remove(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+
+	drm_dev_unregister(drm);
+	mxsfb_unload(drm);
+	drm_dev_unref(drm);
+
+	return 0;
+}
+
+static struct platform_driver mxsfb_platform_driver = {
+	.probe		= mxsfb_probe,
+	.remove		= mxsfb_remove,
+	.id_table	= mxsfb_devtype,
+	.driver	= {
+		.name		= "mxsfb",
+		.of_match_table	= mxsfb_dt_ids,
+	},
+};
+
+module_platform_driver(mxsfb_platform_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("Freescale MXS DRM/KMS driver");
+MODULE_LICENSE("GPL");

drivers/gpu/drm/mxsfb/mxsfb_drv.h

+/*
+ * Copyright (C) 2016 Marek Vasut <marex@denx.de>
+ *
+ * i.MX23/i.MX28/i.MX6SX MXSFB LCD controller driver.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MXSFB_DRV_H__
+#define __MXSFB_DRV_H__
+
+struct mxsfb_devdata {
+	unsigned int	 transfer_count;
+	unsigned int	 cur_buf;
+	unsigned int	 next_buf;
+	unsigned int	 debug0;
+	unsigned int	 hs_wdth_mask;
+	unsigned int	 hs_wdth_shift;
+	unsigned int	 ipversion;
+};
+
+struct mxsfb_drm_private {
+	const struct mxsfb_devdata	*devdata;
+
+	void __iomem			*base;	/* registers */
+	struct clk			*clk;
+	struct clk			*clk_axi;
+	struct clk			*clk_disp_axi;
+
+	struct drm_simple_display_pipe	pipe;
+	struct drm_connector		connector;
+	struct drm_panel		*panel;
+	struct drm_fbdev_cma		*fbdev;
+};
+
+int mxsfb_setup_crtc(struct drm_device *dev);
+int mxsfb_create_output(struct drm_device *dev);
+
+void mxsfb_enable_axi_clk(struct mxsfb_drm_private *mxsfb);
+void mxsfb_disable_axi_clk(struct mxsfb_drm_private *mxsfb);
+
+void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb);
+void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb);
+void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb,
+			       struct drm_plane_state *state);
+
+#endif /* __MXSFB_DRV_H__ */

drivers/gpu/drm/mxsfb/mxsfb_out.c

+/*
+ * Copyright (C) 2016 Marek Vasut <marex@denx.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/of_graph.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <drm/drmP.h>
+
+#include "mxsfb_drv.h"
+
+static struct mxsfb_drm_private *
+drm_connector_to_mxsfb_drm_private(struct drm_connector *connector)
+{
+	return container_of(connector, struct mxsfb_drm_private, connector);
+}
+
+static int mxsfb_panel_get_modes(struct drm_connector *connector)
+{
+	struct mxsfb_drm_private *mxsfb =
+			drm_connector_to_mxsfb_drm_private(connector);
+
+	if (mxsfb->panel)
+		return mxsfb->panel->funcs->get_modes(mxsfb->panel);
+
+	return 0;
+}
+
+static const struct
+drm_connector_helper_funcs mxsfb_panel_connector_helper_funcs = {
+	.get_modes = mxsfb_panel_get_modes,
+};
+
+static enum drm_connector_status
+mxsfb_panel_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct mxsfb_drm_private *mxsfb =
+			drm_connector_to_mxsfb_drm_private(connector);
+
+	if (mxsfb->panel)
+		return connector_status_connected;
+
+	return connector_status_disconnected;
+}
+
+static void mxsfb_panel_connector_destroy(struct drm_connector *connector)
+{
+	struct mxsfb_drm_private *mxsfb =
+			drm_connector_to_mxsfb_drm_private(connector);
+
+	if (mxsfb->panel)
+		drm_panel_detach(mxsfb->panel);
+
+	drm_connector_unregister(connector);
+	drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs mxsfb_panel_connector_funcs = {
+	.dpms			= drm_atomic_helper_connector_dpms,
+	.detect			= mxsfb_panel_connector_detect,
+	.fill_modes		= drm_helper_probe_single_connector_modes,
+	.destroy		= mxsfb_panel_connector_destroy,
+	.reset			= drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
+};
+
+static int mxsfb_attach_endpoint(struct drm_device *drm,
+				 const struct of_endpoint *ep)
+{
+	struct mxsfb_drm_private *mxsfb = drm->dev_private;
+	struct device_node *np;
+	struct drm_panel *panel;
+	int ret = -EPROBE_DEFER;
+
+	np = of_graph_get_remote_port_parent(ep->local_node);
+	panel = of_drm_find_panel(np);
+	of_node_put(np);
+
+	if (!panel)
+		return -EPROBE_DEFER;
+
+	mxsfb->connector.dpms = DRM_MODE_DPMS_OFF;
+	mxsfb->connector.polled = 0;
+	drm_connector_helper_add(&mxsfb->connector,
+			&mxsfb_panel_connector_helper_funcs);
+	ret = drm_connector_init(drm, &mxsfb->connector,
+				 &mxsfb_panel_connector_funcs,
+				 DRM_MODE_CONNECTOR_Unknown);
+	if (!ret)
+		mxsfb->panel = panel;
+
+	return ret;
+}
+
+int mxsfb_create_output(struct drm_device *drm)
+{
+	struct device_node *ep_np = NULL;
+	struct of_endpoint ep;
+	int ret;
+
+	for_each_endpoint_of_node(drm->dev->of_node, ep_np) {
+		ret = of_graph_parse_endpoint(ep_np, &ep);
+		if (!ret)
+			ret = mxsfb_attach_endpoint(drm, &ep);
+
+		if (ret) {
+			of_node_put(ep_np);
+			return ret;
+		}
+	}
+
+	return 0;
+}

drivers/gpu/drm/mxsfb/mxsfb_regs.h

+/*
+ * Copyright (C) 2010 Juergen Beisert, Pengutronix
+ * Copyright (C) 2016 Marek Vasut <marex@denx.de>
+ *
+ * i.MX23/i.MX28/i.MX6SX MXSFB LCD controller driver.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MXSFB_REGS_H__
+#define __MXSFB_REGS_H__
+
+#define REG_SET	4
+#define REG_CLR	8
+
+#define LCDC_CTRL			0x00
+#define LCDC_CTRL1			0x10
+#define LCDC_V3_TRANSFER_COUNT		0x20
+#define LCDC_V4_TRANSFER_COUNT		0x30
+#define LCDC_V4_CUR_BUF			0x40
+#define LCDC_V4_NEXT_BUF		0x50
+#define LCDC_V3_CUR_BUF			0x30
+#define LCDC_V3_NEXT_BUF		0x40
+#define LCDC_VDCTRL0			0x70
+#define LCDC_VDCTRL1			0x80
+#define LCDC_VDCTRL2			0x90
+#define LCDC_VDCTRL3			0xa0
+#define LCDC_VDCTRL4			0xb0
+#define LCDC_V4_DEBUG0			0x1d0
+#define LCDC_V3_DEBUG0			0x1f0
+
+#define CTRL_SFTRST			(1 << 31)
+#define CTRL_CLKGATE			(1 << 30)
+#define CTRL_BYPASS_COUNT		(1 << 19)
+#define CTRL_VSYNC_MODE			(1 << 18)
+#define CTRL_DOTCLK_MODE		(1 << 17)
+#define CTRL_DATA_SELECT		(1 << 16)
+#define CTRL_SET_BUS_WIDTH(x)		(((x) & 0x3) << 10)
+#define CTRL_GET_BUS_WIDTH(x)		(((x) >> 10) & 0x3)
+#define CTRL_SET_WORD_LENGTH(x)		(((x) & 0x3) << 8)
+#define CTRL_GET_WORD_LENGTH(x)		(((x) >> 8) & 0x3)
+#define CTRL_MASTER			(1 << 5)
+#define CTRL_DF16			(1 << 3)
+#define CTRL_DF18			(1 << 2)
+#define CTRL_DF24			(1 << 1)
+#define CTRL_RUN			(1 << 0)
+
+#define CTRL1_FIFO_CLEAR		(1 << 21)
+#define CTRL1_SET_BYTE_PACKAGING(x)	(((x) & 0xf) << 16)
+#define CTRL1_GET_BYTE_PACKAGING(x)	(((x) >> 16) & 0xf)
+#define CTRL1_CUR_FRAME_DONE_IRQ_EN	(1 << 13)
+#define CTRL1_CUR_FRAME_DONE_IRQ	(1 << 9)
+
+#define TRANSFER_COUNT_SET_VCOUNT(x)	(((x) & 0xffff) << 16)
+#define TRANSFER_COUNT_GET_VCOUNT(x)	(((x) >> 16) & 0xffff)
+#define TRANSFER_COUNT_SET_HCOUNT(x)	((x) & 0xffff)
+#define TRANSFER_COUNT_GET_HCOUNT(x)	((x) & 0xffff)
+
+#define VDCTRL0_ENABLE_PRESENT		(1 << 28)
+#define VDCTRL0_VSYNC_ACT_HIGH		(1 << 27)
+#define VDCTRL0_HSYNC_ACT_HIGH		(1 << 26)
+#define VDCTRL0_DOTCLK_ACT_FALLING	(1 << 25)
+#define VDCTRL0_ENABLE_ACT_HIGH		(1 << 24)
+#define VDCTRL0_VSYNC_PERIOD_UNIT	(1 << 21)
+#define VDCTRL0_VSYNC_PULSE_WIDTH_UNIT	(1 << 20)
+#define VDCTRL0_HALF_LINE		(1 << 19)
+#define VDCTRL0_HALF_LINE_MODE		(1 << 18)
+#define VDCTRL0_SET_VSYNC_PULSE_WIDTH(x) ((x) & 0x3ffff)
+#define VDCTRL0_GET_VSYNC_PULSE_WIDTH(x) ((x) & 0x3ffff)
+
+#define VDCTRL2_SET_HSYNC_PERIOD(x)	((x) & 0x3ffff)
+#define VDCTRL2_GET_HSYNC_PERIOD(x)	((x) & 0x3ffff)
+
+#define VDCTRL3_MUX_SYNC_SIGNALS	(1 << 29)
+#define VDCTRL3_VSYNC_ONLY		(1 << 28)
+#define SET_HOR_WAIT_CNT(x)		(((x) & 0xfff) << 16)
+#define GET_HOR_WAIT_CNT(x)		(((x) >> 16) & 0xfff)
+#define SET_VERT_WAIT_CNT(x)		((x) & 0xffff)
+#define GET_VERT_WAIT_CNT(x)		((x) & 0xffff)
+
+#define VDCTRL4_SET_DOTCLK_DLY(x)	(((x) & 0x7) << 29) /* v4 only */
+#define VDCTRL4_GET_DOTCLK_DLY(x)	(((x) >> 29) & 0x7) /* v4 only */
+#define VDCTRL4_SYNC_SIGNALS_ON		(1 << 18)
+#define SET_DOTCLK_H_VALID_DATA_CNT(x)	((x) & 0x3ffff)
+
+#define DEBUG0_HSYNC			(1 < 26)
+#define DEBUG0_VSYNC			(1 < 25)
+
+#define MXSFB_MIN_XRES			120
+#define MXSFB_MIN_YRES			120
+#define MXSFB_MAX_XRES			0xffff
+#define MXSFB_MAX_YRES			0xffff
+
+#define RED 0
+#define GREEN 1
+#define BLUE 2
+#define TRANSP 3
+
+#define STMLCDIF_8BIT  1 /* pixel data bus to the display is of 8 bit width */
+#define STMLCDIF_16BIT 0 /* pixel data bus to the display is of 16 bit width */
+#define STMLCDIF_18BIT 2 /* pixel data bus to the display is of 18 bit width */
+#define STMLCDIF_24BIT 3 /* pixel data bus to the display is of 24 bit width */
+
+#define MXSFB_SYNC_DATA_ENABLE_HIGH_ACT	(1 << 6)
+#define MXSFB_SYNC_DOTCLK_FALLING_ACT	(1 << 7) /* negative edge sampling */
+
+#endif /* __MXSFB_REGS_H__ */