video: omap: add support for DM/DTS

Update the driver to support the device tree and the driver model.
Timings and panel parameters are now loaded from the device tree.

The DM code replaces the am335x_lcdpanel structure with
tilcdc_panel_info taken from the linux kernel, as well the management
of additional parameters not covered in the legacy code. In addition,
the am335x_lcdpanel structure contains parameters and operations that
were probably a requirement of the board for which this driver was
developed and which, however, were not developed in the linux kernel.
All this led to rewrite th DM controller initialization code, except
for the pixel clock setting that is executed in a function created in a
previous patch with code taken from the legacy am335xfb_init.

The patch has been tested on a custom board with u-boot 2018.11-rc2 and
the following device-tree configuration:

	panel {
		compatible = "ti,tilcdc,panel";
		pinctrl-names = "default";
		pinctrl-0 = <&lcd_enable_pins>;
		enable-gpios = <&gpio0 31 0>;
		backlight = <&backlight>;
		status = "okay";
		u-boot,dm-pre-reloc;
		panel-info {
			ac-bias           = <255>;
			ac-bias-intrpt    = <0>;
			dma-burst-sz      = <16>;
			bpp               = <16>;
			fdd               = <0x80>;
			sync-edge         = <0>;
			sync-ctrl         = <1>;
			raster-order      = <0>;
			fifo-th           = <0>;
		};
		display-timings {
			native-mode = <&timing0>;
			timing0: 800x480 {
				hactive         = <800>;
				vactive         = <480>;
				hback-porch     = <46>;
				hfront-porch    = <210>;
				hsync-len       = <20>;
				vback-porch     = <23>;
				vfront-porch    = <22>;
				vsync-len       = <10>;
				clock-frequency = <33000000>;
				hsync-active    = <0>;
				vsync-active    = <0>;
			};
		};
	};

Signed-off-by: Dario Binacchi <dariobin@libero.it>
Tested-by: Dario Binacchi <dariobin@libero.it>

3 files changed, 337 insertions, 10 deletions

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 4c93369702..7c5012a67f 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -473,6 +473,12 @@ config ATMEL_HLCD
 	help
 	   HLCDC supports video output to an attached LCD panel.
 
+config AM335X_LCD
+	bool "Enable AM335x video support"
+	depends on DM_VIDEO
+	help
+	   Supports video output to an attached LCD panel.
+
 config LOGICORE_DP_TX
 	bool "Enable Logicore DP TX driver"
 	depends on DISPLAY
diff --git a/drivers/video/am335x-fb.c b/drivers/video/am335x-fb.c
index c426ff8aec..30543a945b 100644
--- a/drivers/video/am335x-fb.c
+++ b/drivers/video/am335x-fb.c
@@ -2,6 +2,7 @@
 /*
  * Copyright (C) 2013-2018 Hannes Schmelzer <oe5hpm@oevsv.at>
  * B&R Industrial Automation GmbH - http://www.br-automation.com
+ * Copyright (C) 2020 Dario Binacchi <dariobin@libero.it>
  *
  * minimal framebuffer driver for TI's AM335x SoC to be compatible with
  * Wolfgang Denk's LCD-Framework (CONFIG_LCD, common/lcd.c)
@@ -11,19 +12,18 @@
  * - starts output DMA from gd->fb_base buffer
  */
 #include <common.h>
+#include <dm.h>
 #include <asm/io.h>
 #include <asm/arch/hardware.h>
 #include <asm/arch/omap.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/sys_proto.h>
+#include <asm/utils.h>
 #include <linux/err.h>
 #include <lcd.h>
+#include <video.h>
 #include "am335x-fb.h"
 
-#if !defined(LCD_CNTL_BASE)
-#error "hw-base address of LCD-Controller (LCD_CNTL_BASE) not defined!"
-#endif
-
 #define LCDC_FMAX				200000000
 
 /* LCD Control Register */
@@ -41,6 +41,7 @@
 #define LCDC_DMA_CTRL_BURST_4			0x2
 #define LCDC_DMA_CTRL_BURST_8			0x3
 #define LCDC_DMA_CTRL_BURST_16			0x4
+#define LCDC_DMA_CTRL_FIFO_TH(x)		(((x) & GENMASK(2, 0)) << 8)
 /* LCD Timing_0 Register */
 #define LCDC_RASTER_TIMING_0_HORMSB(x)		(((((x) >> 4) - 1) & 0x40) >> 4)
 #define LCDC_RASTER_TIMING_0_HORLSB(x) (((((x) >> 4) - 1) & GENMASK(5, 0)) << 4)
@@ -55,19 +56,26 @@
 /* LCD Timing_2 Register */
 #define LCDC_RASTER_TIMING_2_HFPMSB(x)	((((x) - 1) & GENMASK(9, 8)) >> 8)
 #define LCDC_RASTER_TIMING_2_HBPMSB(x)	((((x) - 1) & GENMASK(9, 8)) >> 4)
-#define LCDC_RASTER_TIMING_2_INVMASK(x)		((x) & GENMASK(25, 20))
+#define LCDC_RASTER_TIMING_2_ACB(x)		(((x) & GENMASK(7, 0)) << 8)
+#define LCDC_RASTER_TIMING_2_ACBI(x)		(((x) & GENMASK(3, 0)) << 16)
+#define LCDC_RASTER_TIMING_2_VSYNC_INVERT	BIT(20)
+#define LCDC_RASTER_TIMING_2_HSYNC_INVERT	BIT(21)
+#define LCDC_RASTER_TIMING_2_PXCLK_INVERT	BIT(22)
+#define LCDC_RASTER_TIMING_2_DE_INVERT		BIT(23)
+#define LCDC_RASTER_TIMING_2_HSVS_RISEFALL	BIT(24)
+#define LCDC_RASTER_TIMING_2_HSVS_CONTROL	BIT(25)
 #define LCDC_RASTER_TIMING_2_VERMSB(x)		((((x) - 1) & BIT(10)) << 16)
 #define LCDC_RASTER_TIMING_2_HSWMSB(x)	((((x) - 1) & GENMASK(9, 6)) << 21)
 /* LCD Raster Ctrl Register */
 #define LCDC_RASTER_CTRL_ENABLE			BIT(0)
 #define LCDC_RASTER_CTRL_TFT_MODE		BIT(7)
+#define LCDC_RASTER_CTRL_DATA_ORDER		BIT(8)
+#define LCDC_RASTER_CTRL_REQDLY(x)		(((x) & GENMASK(7, 0)) << 12)
 #define LCDC_RASTER_CTRL_PALMODE_RAWDATA	(0x02 << 20)
+#define LCDC_RASTER_CTRL_TFT_ALT_ENABLE		BIT(23)
 #define LCDC_RASTER_CTRL_TFT_24BPP_MODE		BIT(25)
 #define LCDC_RASTER_CTRL_TFT_24BPP_UNPACK	BIT(26)
 
-/* Macro definitions */
-#define FBSIZE(x)	((x->hactive * x->vactive * x->bpp) >> 3)
-
 struct am335x_lcdhw {
 	unsigned int		pid;			/* 0x00 */
 	unsigned int		ctrl;			/* 0x04 */
@@ -107,8 +115,6 @@ struct dpll_data {
 	u8 rounded_div;
 };
 
-static struct am335x_lcdhw *lcdhw = (void *)LCD_CNTL_BASE;
-
 DECLARE_GLOBAL_DATA_PTR;
 
 /**
@@ -189,6 +195,19 @@ static ulong am335x_fb_set_pixel_clk_rate(struct am335x_lcdhw *regs, ulong rate)
 	return round_rate;
 }
 
+#if !CONFIG_IS_ENABLED(DM_VIDEO)
+
+#if !defined(LCD_CNTL_BASE)
+#error "hw-base address of LCD-Controller (LCD_CNTL_BASE) not defined!"
+#endif
+
+/* Macro definitions */
+#define FBSIZE(x)	(((x)->hactive * (x)->vactive * (x)->bpp) >> 3)
+
+#define LCDC_RASTER_TIMING_2_INVMASK(x)		((x) & GENMASK(25, 20))
+
+static struct am335x_lcdhw *lcdhw = (void *)LCD_CNTL_BASE;
+
 int lcd_get_size(int *line_length)
 {
 	*line_length = (panel_info.vl_col * NBITS(panel_info.vl_bpix)) / 8;
@@ -299,3 +318,301 @@ int am335xfb_init(struct am335x_lcdpanel *panel)
 
 	return 0;
 }
+
+#else /* CONFIG_DM_VIDEO */
+
+#define FBSIZE(t, p)	(((t)->hactive.typ * (t)->vactive.typ * (p)->bpp) >> 3)
+
+enum {
+	LCD_MAX_WIDTH		= 2048,
+	LCD_MAX_HEIGHT		= 2048,
+	LCD_MAX_LOG2_BPP	= VIDEO_BPP32,
+};
+
+/**
+ * tilcdc_panel_info: Panel parameters
+ *
+ * @ac_bias: AC Bias Pin Frequency
+ * @ac_bias_intrpt: AC Bias Pin Transitions per Interrupt
+ * @dma_burst_sz: DMA burst size
+ * @bpp: Bits per pixel
+ * @fdd: FIFO DMA Request Delay
+ * @tft_alt_mode: TFT Alternative Signal Mapping (Only for active)
+ * @invert_pxl_clk: Invert pixel clock
+ * @sync_edge: Horizontal and Vertical Sync Edge: 0=rising 1=falling
+ * @sync_ctrl: Horizontal and Vertical Sync: Control: 0=ignore
+ * @raster_order: Raster Data Order Select: 1=Most-to-least 0=Least-to-most
+ * @fifo_th: DMA FIFO threshold
+ */
+struct tilcdc_panel_info {
+	u32 ac_bias;
+	u32 ac_bias_intrpt;
+	u32 dma_burst_sz;
+	u32 bpp;
+	u32 fdd;
+	bool tft_alt_mode;
+	bool invert_pxl_clk;
+	u32 sync_edge;
+	u32 sync_ctrl;
+	u32 raster_order;
+	u32 fifo_th;
+};
+
+struct am335x_fb_priv {
+	struct am335x_lcdhw *regs;
+	struct tilcdc_panel_info panel;
+	struct display_timing timing;
+};
+
+static int am335x_fb_remove(struct udevice *dev)
+{
+	struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+
+	uc_plat->base -= 0x20;
+	uc_plat->size += 0x20;
+	return 0;
+}
+
+static int am335x_fb_probe(struct udevice *dev)
+{
+	struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct am335x_fb_priv *priv = dev_get_priv(dev);
+	struct am335x_lcdhw *regs = priv->regs;
+	struct tilcdc_panel_info *panel = &priv->panel;
+	struct display_timing *timing = &priv->timing;
+	struct cm_dpll *const cmdpll = (struct cm_dpll *)CM_DPLL;
+	u32 reg;
+
+	/* Before relocation we don't need to do anything */
+	if (!(gd->flags & GD_FLG_RELOC))
+		return 0;
+
+	am335x_fb_set_pixel_clk_rate(regs, timing->pixelclock.typ);
+
+	/* clock source for LCDC from dispPLL M2 */
+	writel(0, &cmdpll->clklcdcpixelclk);
+
+	/* palette default entry */
+	memset((void *)uc_plat->base, 0, 0x20);
+	*(unsigned int *)uc_plat->base = 0x4000;
+	/* point fb behind palette */
+	uc_plat->base += 0x20;
+	uc_plat->size -= 0x20;
+
+	writel(LCDC_CLKC_ENABLE_CORECLKEN | LCDC_CLKC_ENABLE_LIDDCLKEN |
+	       LCDC_CLKC_ENABLE_DMACLKEN, &regs->clkc_enable);
+	writel(0, &regs->raster_ctrl);
+
+	reg = readl(&regs->ctrl) & LCDC_CTRL_CLK_DIVISOR_MASK;
+	reg |= LCDC_CTRL_RASTER_MODE;
+	writel(reg, &regs->ctrl);
+
+	writel(uc_plat->base, &regs->lcddma_fb0_base);
+	writel(uc_plat->base + FBSIZE(timing, panel),
+	       &regs->lcddma_fb0_ceiling);
+	writel(uc_plat->base, &regs->lcddma_fb1_base);
+	writel(uc_plat->base + FBSIZE(timing, panel),
+	       &regs->lcddma_fb1_ceiling);
+
+	reg = LCDC_DMA_CTRL_FIFO_TH(panel->fifo_th);
+	switch (panel->dma_burst_sz) {
+	case 1:
+		reg |= LCDC_DMA_CTRL_BURST_SIZE(LCDC_DMA_CTRL_BURST_1);
+		break;
+	case 2:
+		reg |= LCDC_DMA_CTRL_BURST_SIZE(LCDC_DMA_CTRL_BURST_2);
+		break;
+	case 4:
+		reg |= LCDC_DMA_CTRL_BURST_SIZE(LCDC_DMA_CTRL_BURST_4);
+		break;
+	case 8:
+		reg |= LCDC_DMA_CTRL_BURST_SIZE(LCDC_DMA_CTRL_BURST_8);
+		break;
+	case 16:
+		reg |= LCDC_DMA_CTRL_BURST_SIZE(LCDC_DMA_CTRL_BURST_16);
+		break;
+	}
+
+	writel(reg, &regs->lcddma_ctrl);
+
+	writel(LCDC_RASTER_TIMING_0_HORLSB(timing->hactive.typ) |
+	       LCDC_RASTER_TIMING_0_HORMSB(timing->hactive.typ) |
+	       LCDC_RASTER_TIMING_0_HFPLSB(timing->hfront_porch.typ) |
+	       LCDC_RASTER_TIMING_0_HBPLSB(timing->hback_porch.typ) |
+	       LCDC_RASTER_TIMING_0_HSWLSB(timing->hsync_len.typ),
+	       &regs->raster_timing0);
+
+	writel(LCDC_RASTER_TIMING_1_VBP(timing->vback_porch.typ) |
+	       LCDC_RASTER_TIMING_1_VFP(timing->vfront_porch.typ) |
+	       LCDC_RASTER_TIMING_1_VSW(timing->vsync_len.typ) |
+	       LCDC_RASTER_TIMING_1_VERLSB(timing->vactive.typ),
+	       &regs->raster_timing1);
+
+	reg = LCDC_RASTER_TIMING_2_ACB(panel->ac_bias) |
+		LCDC_RASTER_TIMING_2_ACBI(panel->ac_bias_intrpt) |
+		LCDC_RASTER_TIMING_2_HSWMSB(timing->hsync_len.typ) |
+		LCDC_RASTER_TIMING_2_VERMSB(timing->vactive.typ) |
+		LCDC_RASTER_TIMING_2_HBPMSB(timing->hback_porch.typ) |
+		LCDC_RASTER_TIMING_2_HFPMSB(timing->hfront_porch.typ);
+
+	if (timing->flags & DISPLAY_FLAGS_VSYNC_LOW)
+		reg |= LCDC_RASTER_TIMING_2_VSYNC_INVERT;
+
+	if (timing->flags & DISPLAY_FLAGS_HSYNC_LOW)
+		reg |= LCDC_RASTER_TIMING_2_HSYNC_INVERT;
+
+	if (panel->invert_pxl_clk)
+		reg |= LCDC_RASTER_TIMING_2_PXCLK_INVERT;
+
+	if (panel->sync_edge)
+		reg |= LCDC_RASTER_TIMING_2_HSVS_RISEFALL;
+
+	if (panel->sync_ctrl)
+		reg |= LCDC_RASTER_TIMING_2_HSVS_CONTROL;
+
+	writel(reg, &regs->raster_timing2);
+
+	reg = LCDC_RASTER_CTRL_PALMODE_RAWDATA | LCDC_RASTER_CTRL_TFT_MODE |
+		LCDC_RASTER_CTRL_ENABLE | LCDC_RASTER_CTRL_REQDLY(panel->fdd);
+
+	if (panel->tft_alt_mode)
+		reg |= LCDC_RASTER_CTRL_TFT_ALT_ENABLE;
+
+	if (panel->bpp == 24)
+		reg |= LCDC_RASTER_CTRL_TFT_24BPP_MODE;
+	else if (panel->bpp == 32)
+		reg |= LCDC_RASTER_CTRL_TFT_24BPP_MODE |
+			LCDC_RASTER_CTRL_TFT_24BPP_UNPACK;
+
+	if (panel->raster_order)
+		reg |= LCDC_RASTER_CTRL_DATA_ORDER;
+
+	writel(reg, &regs->raster_ctrl);
+
+	uc_priv->xsize = timing->hactive.typ;
+	uc_priv->ysize = timing->vactive.typ;
+	uc_priv->bpix = log_2_n_round_up(panel->bpp);
+	return 0;
+}
+
+static int am335x_fb_ofdata_to_platdata(struct udevice *dev)
+{
+	struct am335x_fb_priv *priv = dev_get_priv(dev);
+	struct tilcdc_panel_info *panel = &priv->panel;
+	struct display_timing *timing = &priv->timing;
+	ofnode node;
+	int err;
+
+	node = ofnode_by_compatible(ofnode_null(), "ti,am33xx-tilcdc");
+	if (!ofnode_valid(node)) {
+		dev_err(dev, "missing 'ti,am33xx-tilcdc' node\n");
+		return -ENXIO;
+	}
+
+	priv->regs = (struct am335x_lcdhw *)ofnode_get_addr(node);
+	dev_dbg(dev, "LCD: base address=0x%x\n", (unsigned int)priv->regs);
+
+	err = ofnode_decode_display_timing(dev_ofnode(dev), 0, timing);
+	if (err) {
+		dev_err(dev, "failed to get display timing\n");
+		return err;
+	}
+
+	if (timing->pixelclock.typ > (LCDC_FMAX / 2)) {
+		dev_err(dev, "invalid display clock-frequency: %d Hz\n",
+			timing->pixelclock.typ);
+		return -EINVAL;
+	}
+
+	if (timing->hactive.typ > LCD_MAX_WIDTH)
+		timing->hactive.typ = LCD_MAX_WIDTH;
+
+	if (timing->vactive.typ > LCD_MAX_HEIGHT)
+		timing->vactive.typ = LCD_MAX_HEIGHT;
+
+	node = ofnode_find_subnode(dev_ofnode(dev), "panel-info");
+	if (!ofnode_valid(node)) {
+		dev_err(dev, "missing 'panel-info' node\n");
+		return -ENXIO;
+	}
+
+	err |= ofnode_read_u32(node, "ac-bias", &panel->ac_bias);
+	err |= ofnode_read_u32(node, "ac-bias-intrpt", &panel->ac_bias_intrpt);
+	err |= ofnode_read_u32(node, "dma-burst-sz", &panel->dma_burst_sz);
+	err |= ofnode_read_u32(node, "bpp", &panel->bpp);
+	err |= ofnode_read_u32(node, "fdd", &panel->fdd);
+	err |= ofnode_read_u32(node, "sync-edge", &panel->sync_edge);
+	err |= ofnode_read_u32(node, "sync-ctrl", &panel->sync_ctrl);
+	err |= ofnode_read_u32(node, "raster-order", &panel->raster_order);
+	err |= ofnode_read_u32(node, "fifo-th", &panel->fifo_th);
+	if (err) {
+		dev_err(dev, "failed to get panel info\n");
+		return err;
+	}
+
+	switch (panel->bpp) {
+	case 16:
+	case 24:
+	case 32:
+		break;
+	default:
+		dev_err(dev, "invalid seting, bpp: %d\n", panel->bpp);
+		return -EINVAL;
+	}
+
+	switch (panel->dma_burst_sz) {
+	case 1:
+	case 2:
+	case 4:
+	case 8:
+	case 16:
+		break;
+	default:
+		dev_err(dev, "invalid setting, dma-burst-sz: %d\n",
+			panel->dma_burst_sz);
+		return -EINVAL;
+	}
+
+	/* optional */
+	panel->tft_alt_mode = ofnode_read_bool(node, "tft-alt-mode");
+	panel->invert_pxl_clk = ofnode_read_bool(node, "invert-pxl-clk");
+
+	dev_dbg(dev, "LCD: %dx%d, bpp=%d, clk=%d Hz\n", timing->hactive.typ,
+		timing->vactive.typ, panel->bpp, timing->pixelclock.typ);
+	dev_dbg(dev, "     hbp=%d, hfp=%d, hsw=%d\n", timing->hback_porch.typ,
+		timing->hfront_porch.typ, timing->hsync_len.typ);
+	dev_dbg(dev, "     vbp=%d, vfp=%d, vsw=%d\n", timing->vback_porch.typ,
+		timing->vfront_porch.typ, timing->vsync_len.typ);
+
+	return 0;
+}
+
+static int am335x_fb_bind(struct udevice *dev)
+{
+	struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+
+	uc_plat->size = ((LCD_MAX_WIDTH * LCD_MAX_HEIGHT *
+			  (1 << LCD_MAX_LOG2_BPP)) >> 3) + 0x20;
+
+	dev_dbg(dev, "frame buffer size 0x%x\n", uc_plat->size);
+	return 0;
+}
+
+static const struct udevice_id am335x_fb_ids[] = {
+	{ .compatible = "ti,tilcdc,panel" },
+	{ }
+};
+
+U_BOOT_DRIVER(am335x_fb) = {
+	.name = "am335x_fb",
+	.id = UCLASS_VIDEO,
+	.of_match = am335x_fb_ids,
+	.bind = am335x_fb_bind,
+	.ofdata_to_platdata = am335x_fb_ofdata_to_platdata,
+	.probe = am335x_fb_probe,
+	.remove = am335x_fb_remove,
+	.priv_auto_alloc_size = sizeof(struct am335x_fb_priv),
+};
+
+#endif /* CONFIG_DM_VIDEO */
diff --git a/drivers/video/am335x-fb.h b/drivers/video/am335x-fb.h
index ad9b015e09..c9f92bc389 100644
--- a/drivers/video/am335x-fb.h
+++ b/drivers/video/am335x-fb.h
@@ -7,6 +7,8 @@
 #ifndef AM335X_FB_H
 #define AM335X_FB_H
 
+#if !CONFIG_IS_ENABLED(DM_VIDEO)
+
 #define HSVS_CONTROL		BIT(25)	/*
 					 * 0 = lcd_lp and lcd_fp are driven on
 					 * opposite edges of pixel clock than
@@ -68,4 +70,6 @@ struct am335x_lcdpanel {
 
 int am335xfb_init(struct am335x_lcdpanel *panel);
 
+#endif  /* CONFIG_DM_VIDEO */
+
 #endif  /* AM335X_FB_H */