mx6sabresd: Add LVDS splash screen support

mx6sabresd boards can be connected to a Hannstar XGA LVDS panel.

Add support for displaying U-boot splashscreen on it.

By default, HDMI splash is selected.

In order to use splash via LVDS, do the following in the U-boot prompt:

setenv panel Hannstar-XGA
save

and reboot.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>

board/freescale/mx6sabresd/mx6sabresd.c

@@ -234,7 +234,42 @@ int board_phy_config(struct phy_device *phydev)
 }
 
 #if defined(CONFIG_VIDEO_IPUV3)
-static struct fb_videomode const hdmi = {
+struct display_info_t {
+	int	bus;
+	int	addr;
+	int	pixfmt;
+	int	(*detect)(struct display_info_t const *dev);
+	void	(*enable)(struct display_info_t const *dev);
+	struct	fb_videomode mode;
+};
+
+static int detect_hdmi(struct display_info_t const *dev)
+{
+	struct hdmi_regs *hdmi	= (struct hdmi_regs *)HDMI_ARB_BASE_ADDR;
+	return readb(&hdmi->phy_stat0) & HDMI_DVI_STAT;
+}
+
+static void do_enable_hdmi(struct display_info_t const *dev)
+{
+	imx_enable_hdmi_phy();
+}
+
+static void enable_lvds(struct display_info_t const *dev)
+{
+	struct iomuxc *iomux = (struct iomuxc *)
+				IOMUXC_BASE_ADDR;
+	u32 reg = readl(&iomux->gpr[2]);
+	reg |= IOMUXC_GPR2_DATA_WIDTH_CH0_24BIT |
+	       IOMUXC_GPR2_DATA_WIDTH_CH1_24BIT;
+	writel(reg, &iomux->gpr[2]);
+}
+static struct display_info_t const displays[] = {{
+	.bus	= -1,
+	.addr	= 0,
+	.pixfmt	= IPU_PIX_FMT_RGB24,
+	.detect	= detect_hdmi,
+	.enable	= do_enable_hdmi,
+	.mode	= {
 		.name           = "HDMI",
 		.refresh        = 60,
 		.xres           = 1024,
@@ -248,33 +283,122 @@ static struct fb_videomode const hdmi = {
 		.vsync_len      = 10,
 		.sync           = FB_SYNC_EXT,
 		.vmode          = FB_VMODE_NONINTERLACED
-};
+} }, {
+	.bus	= -1,
+	.addr	= 0,
+	.pixfmt	= IPU_PIX_FMT_LVDS666,
+	.detect	= NULL,
+	.enable	= enable_lvds,
+	.mode	= {
+		.name           = "Hannstar-XGA",
+		.refresh        = 60,
+		.xres           = 1024,
+		.yres           = 768,
+		.pixclock       = 15385,
+		.left_margin    = 220,
+		.right_margin   = 40,
+		.upper_margin   = 21,
+		.lower_margin   = 7,
+		.hsync_len      = 60,
+		.vsync_len      = 10,
+		.sync           = FB_SYNC_EXT,
+		.vmode          = FB_VMODE_NONINTERLACED
+} } };
 
 int board_video_skip(void)
 {
+	int i;
 	int ret;
+	char const *panel = getenv("panel");
+	if (!panel) {
+		for (i = 0; i < ARRAY_SIZE(displays); i++) {
+			struct display_info_t const *dev = displays+i;
+			if (dev->detect(dev)) {
+				panel = dev->mode.name;
+				printf("auto-detected panel %s\n", panel);
+				break;
+			}
+		}
+		if (!panel) {
+			panel = displays[0].mode.name;
+			printf("No panel detected: default to %s\n", panel);
+		}
+	} else {
+		for (i = 0; i < ARRAY_SIZE(displays); i++) {
+			if (!strcmp(panel, displays[i].mode.name))
+				break;
+		}
+	}
+	if (i < ARRAY_SIZE(displays)) {
+		ret = ipuv3_fb_init(&displays[i].mode, 0,
+				    displays[i].pixfmt);
+		if (!ret) {
+			displays[i].enable(displays+i);
+			printf("Display: %s (%ux%u)\n",
+			       displays[i].mode.name,
+			       displays[i].mode.xres,
+			       displays[i].mode.yres);
+		} else
+			printf("LCD %s cannot be configured: %d\n",
+			       displays[i].mode.name, ret);
+	} else {
+		printf("unsupported panel %s\n", panel);
+		return -EINVAL;
+	}
 
-	ret = ipuv3_fb_init(&hdmi, 0, IPU_PIX_FMT_RGB24);
+	return 0;
-
-	if (ret)
-		printf("HDMI cannot be configured: %d\n", ret);
-
-	imx_enable_hdmi_phy();
-	return ret;
 }
 
 static void setup_display(void)
 {
 	struct mxc_ccm_reg *mxc_ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
+	struct iomuxc *iomux = (struct iomuxc *)IOMUXC_BASE_ADDR;
 	int reg;
 
 	enable_ipu_clock();
 	imx_setup_hdmi();
 
+	/* Turn on LDB0, LDB1, IPU,IPU DI0 clocks */
+	reg = __raw_readl(&mxc_ccm->CCGR3);
+	reg |=  MXC_CCM_CCGR3_LDB_DI0_MASK | MXC_CCM_CCGR3_LDB_DI1_MASK;
+	writel(reg, &mxc_ccm->CCGR3);
+
+	/* set LDB0, LDB1 clk select to 011/011 */
+	reg = readl(&mxc_ccm->cs2cdr);
+	reg &= ~(MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_MASK
+		 | MXC_CCM_CS2CDR_LDB_DI1_CLK_SEL_MASK);
+	reg |= (3 << MXC_CCM_CS2CDR_LDB_DI0_CLK_SEL_OFFSET)
+	      | (3 << MXC_CCM_CS2CDR_LDB_DI1_CLK_SEL_OFFSET);
+	writel(reg, &mxc_ccm->cs2cdr);
+
+	reg = readl(&mxc_ccm->cscmr2);
+	reg |= MXC_CCM_CSCMR2_LDB_DI0_IPU_DIV | MXC_CCM_CSCMR2_LDB_DI1_IPU_DIV;
+	writel(reg, &mxc_ccm->cscmr2);
+
 	reg = readl(&mxc_ccm->chsccdr);
 	reg |= (CHSCCDR_CLK_SEL_LDB_DI0
 		<< MXC_CCM_CHSCCDR_IPU1_DI0_CLK_SEL_OFFSET);
+	reg |= (CHSCCDR_CLK_SEL_LDB_DI0
+		<< MXC_CCM_CHSCCDR_IPU1_DI1_CLK_SEL_OFFSET);
 	writel(reg, &mxc_ccm->chsccdr);
+
+	reg = IOMUXC_GPR2_BGREF_RRMODE_EXTERNAL_RES
+	     | IOMUXC_GPR2_DI1_VS_POLARITY_ACTIVE_LOW
+	     | IOMUXC_GPR2_DI0_VS_POLARITY_ACTIVE_LOW
+	     | IOMUXC_GPR2_BIT_MAPPING_CH1_SPWG
+	     | IOMUXC_GPR2_DATA_WIDTH_CH1_18BIT
+	     | IOMUXC_GPR2_BIT_MAPPING_CH0_SPWG
+	     | IOMUXC_GPR2_DATA_WIDTH_CH0_18BIT
+	     | IOMUXC_GPR2_LVDS_CH0_MODE_DISABLED
+	     | IOMUXC_GPR2_LVDS_CH1_MODE_ENABLED_DI0;
+	writel(reg, &iomux->gpr[2]);
+
+	reg = readl(&iomux->gpr[3]);
+	reg = (reg & ~(IOMUXC_GPR3_LVDS1_MUX_CTL_MASK
+			| IOMUXC_GPR3_HDMI_MUX_CTL_MASK))
+	    | (IOMUXC_GPR3_MUX_SRC_IPU1_DI0
+	       << IOMUXC_GPR3_LVDS1_MUX_CTL_OFFSET);
+	writel(reg, &iomux->gpr[3]);
 }
 #endif /* CONFIG_VIDEO_IPUV3 */