--- /dev/null
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ * Yannick Fertre <yannick.fertre@st.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <panel.h>
+#include <video.h>
+#include <asm/io.h>
+#include <asm/arch/gpio.h>
+#include <dm/device-internal.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct stm32_ltdc_priv {
+ void __iomem *regs;
+ struct display_timing timing;
+ enum video_log2_bpp l2bpp;
+ u32 bg_col_argb;
+ u32 crop_x, crop_y, crop_w, crop_h;
+ u32 alpha;
+};
+
+/* LTDC main registers */
+#define LTDC_IDR 0x00 /* IDentification */
+#define LTDC_LCR 0x04 /* Layer Count */
+#define LTDC_SSCR 0x08 /* Synchronization Size Configuration */
+#define LTDC_BPCR 0x0C /* Back Porch Configuration */
+#define LTDC_AWCR 0x10 /* Active Width Configuration */
+#define LTDC_TWCR 0x14 /* Total Width Configuration */
+#define LTDC_GCR 0x18 /* Global Control */
+#define LTDC_GC1R 0x1C /* Global Configuration 1 */
+#define LTDC_GC2R 0x20 /* Global Configuration 2 */
+#define LTDC_SRCR 0x24 /* Shadow Reload Configuration */
+#define LTDC_GACR 0x28 /* GAmma Correction */
+#define LTDC_BCCR 0x2C /* Background Color Configuration */
+#define LTDC_IER 0x34 /* Interrupt Enable */
+#define LTDC_ISR 0x38 /* Interrupt Status */
+#define LTDC_ICR 0x3C /* Interrupt Clear */
+#define LTDC_LIPCR 0x40 /* Line Interrupt Position Conf. */
+#define LTDC_CPSR 0x44 /* Current Position Status */
+#define LTDC_CDSR 0x48 /* Current Display Status */
+
+/* LTDC layer 1 registers */
+#define LTDC_L1LC1R 0x80 /* L1 Layer Configuration 1 */
+#define LTDC_L1LC2R 0x84 /* L1 Layer Configuration 2 */
+#define LTDC_L1CR 0x84 /* L1 Control */
+#define LTDC_L1WHPCR 0x88 /* L1 Window Hor Position Config */
+#define LTDC_L1WVPCR 0x8C /* L1 Window Vert Position Config */
+#define LTDC_L1CKCR 0x90 /* L1 Color Keying Configuration */
+#define LTDC_L1PFCR 0x94 /* L1 Pixel Format Configuration */
+#define LTDC_L1CACR 0x98 /* L1 Constant Alpha Config */
+#define LTDC_L1DCCR 0x9C /* L1 Default Color Configuration */
+#define LTDC_L1BFCR 0xA0 /* L1 Blend Factors Configuration */
+#define LTDC_L1FBBCR 0xA4 /* L1 FrameBuffer Bus Control */
+#define LTDC_L1AFBCR 0xA8 /* L1 AuxFB Control */
+#define LTDC_L1CFBAR 0xAC /* L1 Color FrameBuffer Address */
+#define LTDC_L1CFBLR 0xB0 /* L1 Color FrameBuffer Length */
+#define LTDC_L1CFBLNR 0xB4 /* L1 Color FrameBuffer Line Nb */
+#define LTDC_L1AFBAR 0xB8 /* L1 AuxFB Address */
+#define LTDC_L1AFBLR 0xBC /* L1 AuxFB Length */
+#define LTDC_L1AFBLNR 0xC0 /* L1 AuxFB Line Number */
+#define LTDC_L1CLUTWR 0xC4 /* L1 CLUT Write */
+
+/* Bit definitions */
+#define SSCR_VSH GENMASK(10, 0) /* Vertical Synchronization Height */
+#define SSCR_HSW GENMASK(27, 16) /* Horizontal Synchronization Width */
+
+#define BPCR_AVBP GENMASK(10, 0) /* Accumulated Vertical Back Porch */
+#define BPCR_AHBP GENMASK(27, 16) /* Accumulated Horizontal Back Porch */
+
+#define AWCR_AAH GENMASK(10, 0) /* Accumulated Active Height */
+#define AWCR_AAW GENMASK(27, 16) /* Accumulated Active Width */
+
+#define TWCR_TOTALH GENMASK(10, 0) /* TOTAL Height */
+#define TWCR_TOTALW GENMASK(27, 16) /* TOTAL Width */
+
+#define GCR_LTDCEN BIT(0) /* LTDC ENable */
+#define GCR_DEN BIT(16) /* Dither ENable */
+#define GCR_PCPOL BIT(28) /* Pixel Clock POLarity-Inverted */
+#define GCR_DEPOL BIT(29) /* Data Enable POLarity-High */
+#define GCR_VSPOL BIT(30) /* Vertical Synchro POLarity-High */
+#define GCR_HSPOL BIT(31) /* Horizontal Synchro POLarity-High */
+
+#define GC1R_WBCH GENMASK(3, 0) /* Width of Blue CHannel output */
+#define GC1R_WGCH GENMASK(7, 4) /* Width of Green Channel output */
+#define GC1R_WRCH GENMASK(11, 8) /* Width of Red Channel output */
+#define GC1R_PBEN BIT(12) /* Precise Blending ENable */
+#define GC1R_DT GENMASK(15, 14) /* Dithering Technique */
+#define GC1R_GCT GENMASK(19, 17) /* Gamma Correction Technique */
+#define GC1R_SHREN BIT(21) /* SHadow Registers ENabled */
+#define GC1R_BCP BIT(22) /* Background Colour Programmable */
+#define GC1R_BBEN BIT(23) /* Background Blending ENabled */
+#define GC1R_LNIP BIT(24) /* Line Number IRQ Position */
+#define GC1R_TP BIT(25) /* Timing Programmable */
+#define GC1R_IPP BIT(26) /* IRQ Polarity Programmable */
+#define GC1R_SPP BIT(27) /* Sync Polarity Programmable */
+#define GC1R_DWP BIT(28) /* Dither Width Programmable */
+#define GC1R_STREN BIT(29) /* STatus Registers ENabled */
+#define GC1R_BMEN BIT(31) /* Blind Mode ENabled */
+
+#define GC2R_EDCA BIT(0) /* External Display Control Ability */
+#define GC2R_STSAEN BIT(1) /* Slave Timing Sync Ability ENabled */
+#define GC2R_DVAEN BIT(2) /* Dual-View Ability ENabled */
+#define GC2R_DPAEN BIT(3) /* Dual-Port Ability ENabled */
+#define GC2R_BW GENMASK(6, 4) /* Bus Width (log2 of nb of bytes) */
+#define GC2R_EDCEN BIT(7) /* External Display Control ENabled */
+
+#define SRCR_IMR BIT(0) /* IMmediate Reload */
+#define SRCR_VBR BIT(1) /* Vertical Blanking Reload */
+
+#define LXCR_LEN BIT(0) /* Layer ENable */
+#define LXCR_COLKEN BIT(1) /* Color Keying Enable */
+#define LXCR_CLUTEN BIT(4) /* Color Look-Up Table ENable */
+
+#define LXWHPCR_WHSTPOS GENMASK(11, 0) /* Window Horizontal StarT POSition */
+#define LXWHPCR_WHSPPOS GENMASK(27, 16) /* Window Horizontal StoP POSition */
+
+#define LXWVPCR_WVSTPOS GENMASK(10, 0) /* Window Vertical StarT POSition */
+#define LXWVPCR_WVSPPOS GENMASK(26, 16) /* Window Vertical StoP POSition */
+
+#define LXPFCR_PF GENMASK(2, 0) /* Pixel Format */
+
+#define LXCACR_CONSTA GENMASK(7, 0) /* CONSTant Alpha */
+
+#define LXBFCR_BF2 GENMASK(2, 0) /* Blending Factor 2 */
+#define LXBFCR_BF1 GENMASK(10, 8) /* Blending Factor 1 */
+
+#define LXCFBLR_CFBLL GENMASK(12, 0) /* Color Frame Buffer Line Length */
+#define LXCFBLR_CFBP GENMASK(28, 16) /* Color Frame Buffer Pitch in bytes */
+
+#define LXCFBLNR_CFBLN GENMASK(10, 0) /* Color Frame Buffer Line Number */
+
+#define BF1_PAXCA 0x600 /* Pixel Alpha x Constant Alpha */
+#define BF2_1PAXCA 0x007 /* 1 - (Pixel Alpha x Constant Alpha) */
+
+enum stm32_ltdc_pix_fmt {
+ PF_ARGB8888 = 0,
+ PF_RGB888,
+ PF_RGB565,
+ PF_ARGB1555,
+ PF_ARGB4444,
+ PF_L8,
+ PF_AL44,
+ PF_AL88
+};
+
+/* TODO add more color format support */
+static u32 stm32_ltdc_get_pixel_format(enum video_log2_bpp l2bpp)
+{
+ enum stm32_ltdc_pix_fmt pf;
+
+ switch (l2bpp) {
+ case VIDEO_BPP16:
+ pf = PF_RGB565;
+ break;
+
+ case VIDEO_BPP1:
+ case VIDEO_BPP2:
+ case VIDEO_BPP4:
+ case VIDEO_BPP8:
+ case VIDEO_BPP32:
+ default:
+ debug("%s: warning %dbpp not supported yet, %dbpp instead\n",
+ __func__, VNBITS(l2bpp), VNBITS(VIDEO_BPP16));
+ pf = PF_RGB565;
+ break;
+ }
+
+ debug("%s: %d bpp -> ltdc pf %d\n", __func__, VNBITS(l2bpp), pf);
+
+ return (u32)pf;
+}
+
+static void stm32_ltdc_enable(struct stm32_ltdc_priv *priv)
+{
+ /* Reload configuration immediately & enable LTDC */
+ setbits_le32(priv->regs + LTDC_SRCR, SRCR_IMR);
+ setbits_le32(priv->regs + LTDC_GCR, GCR_LTDCEN);
+}
+
+static void stm32_ltdc_set_mode(struct stm32_ltdc_priv *priv)
+{
+ void __iomem *regs = priv->regs;
+ struct display_timing *timing = &priv->timing;
+ u32 hsync, vsync, acc_hbp, acc_vbp, acc_act_w, acc_act_h;
+ u32 total_w, total_h;
+ u32 val;
+
+ /* Convert video timings to ltdc timings */
+ hsync = timing->hsync_len.typ - 1;
+ vsync = timing->vsync_len.typ - 1;
+ acc_hbp = hsync + timing->hback_porch.typ;
+ acc_vbp = vsync + timing->vback_porch.typ;
+ acc_act_w = acc_hbp + timing->hactive.typ;
+ acc_act_h = acc_vbp + timing->vactive.typ;
+ total_w = acc_act_w + timing->hfront_porch.typ;
+ total_h = acc_act_h + timing->vfront_porch.typ;
+
+ /* Synchronization sizes */
+ val = (hsync << 16) | vsync;
+ clrsetbits_le32(regs + LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
+
+ /* Accumulated back porch */
+ val = (acc_hbp << 16) | acc_vbp;
+ clrsetbits_le32(regs + LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
+
+ /* Accumulated active width */
+ val = (acc_act_w << 16) | acc_act_h;
+ clrsetbits_le32(regs + LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
+
+ /* Total width & height */
+ val = (total_w << 16) | total_h;
+ clrsetbits_le32(regs + LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
+
+ /* Signal polarities */
+ val = 0;
+ debug("%s: timing->flags 0x%08x\n", __func__, timing->flags);
+ if (timing->flags & DISPLAY_FLAGS_HSYNC_HIGH)
+ val |= GCR_HSPOL;
+ if (timing->flags & DISPLAY_FLAGS_VSYNC_HIGH)
+ val |= GCR_VSPOL;
+ if (timing->flags & DISPLAY_FLAGS_DE_HIGH)
+ val |= GCR_DEPOL;
+ if (timing->flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
+ val |= GCR_PCPOL;
+ clrsetbits_le32(regs + LTDC_GCR,
+ GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
+
+ /* Overall background color */
+ writel(priv->bg_col_argb, priv->regs + LTDC_BCCR);
+}
+
+static void stm32_ltdc_set_layer1(struct stm32_ltdc_priv *priv, ulong fb_addr)
+{
+ void __iomem *regs = priv->regs;
+ u32 x0, x1, y0, y1;
+ u32 pitch_in_bytes;
+ u32 line_length;
+ u32 bus_width;
+ u32 val, tmp, bpp;
+
+ x0 = priv->crop_x;
+ x1 = priv->crop_x + priv->crop_w - 1;
+ y0 = priv->crop_y;
+ y1 = priv->crop_y + priv->crop_h - 1;
+
+ /* Horizontal start and stop position */
+ tmp = (readl(regs + LTDC_BPCR) & BPCR_AHBP) >> 16;
+ val = ((x1 + 1 + tmp) << 16) + (x0 + 1 + tmp);
+ clrsetbits_le32(regs + LTDC_L1WHPCR, LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS,
+ val);
+
+ /* Vertical start & stop position */
+ tmp = readl(regs + LTDC_BPCR) & BPCR_AVBP;
+ val = ((y1 + 1 + tmp) << 16) + (y0 + 1 + tmp);
+ clrsetbits_le32(regs + LTDC_L1WVPCR, LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS,
+ val);
+
+ /* Layer background color */
+ writel(priv->bg_col_argb, regs + LTDC_L1DCCR);
+
+ /* Color frame buffer pitch in bytes & line length */
+ bpp = VNBITS(priv->l2bpp);
+ pitch_in_bytes = priv->crop_w * (bpp >> 3);
+ bus_width = 8 << ((readl(regs + LTDC_GC2R) & GC2R_BW) >> 4);
+ line_length = ((bpp >> 3) * priv->crop_w) + (bus_width >> 3) - 1;
+ val = (pitch_in_bytes << 16) | line_length;
+ clrsetbits_le32(regs + LTDC_L1CFBLR, LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
+
+ /* Pixel format */
+ val = stm32_ltdc_get_pixel_format(priv->l2bpp);
+ clrsetbits_le32(regs + LTDC_L1PFCR, LXPFCR_PF, val);
+
+ /* Constant alpha value */
+ clrsetbits_le32(regs + LTDC_L1CACR, LXCACR_CONSTA, priv->alpha);
+
+ /* Blending factors */
+ clrsetbits_le32(regs + LTDC_L1BFCR, LXBFCR_BF2 | LXBFCR_BF1,
+ BF1_PAXCA | BF2_1PAXCA);
+
+ /* Frame buffer line number */
+ clrsetbits_le32(regs + LTDC_L1CFBLNR, LXCFBLNR_CFBLN, priv->crop_h);
+
+ /* Frame buffer address */
+ writel(fb_addr, regs + LTDC_L1CFBAR);
+
+ /* Enable layer 1 */
+ setbits_le32(priv->regs + LTDC_L1CR, LXCR_LEN);
+}
+
+static int stm32_ltdc_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 stm32_ltdc_priv *priv = dev_get_priv(dev);
+ struct udevice *panel;
+ struct clk pclk, pxclk;
+ int ret;
+
+ priv->regs = (void *)dev_read_addr(dev);
+ if ((fdt_addr_t)priv->regs == FDT_ADDR_T_NONE) {
+ debug("%s: ltdc dt register address error\n", __func__);
+ return -EINVAL;
+ }
+
+ ret = uclass_first_device(UCLASS_PANEL, &panel);
+ if (ret) {
+ debug("%s: panel device error %d\n", __func__, ret);
+ return ret;
+ }
+
+ ret = panel_enable_backlight(panel);
+ if (ret) {
+ debug("%s: panel %s enable backlight error %d\n",
+ __func__, panel->name, ret);
+ return ret;
+ }
+
+ ret = fdtdec_decode_display_timing(gd->fdt_blob, dev_of_offset(dev),
+ 0, &priv->timing);
+ if (ret) {
+ debug("%s: decode display timing error %d\n", __func__, ret);
+ return -EINVAL;
+ }
+
+ ret = clk_get_by_name(dev, "pclk", &pclk);
+ if (ret) {
+ debug("%s: peripheral clock get error %d\n", __func__, ret);
+ return ret;
+ }
+
+ ret = clk_enable(&pclk);
+ if (ret) {
+ debug("%s: peripheral clock enable error %d\n", __func__, ret);
+ return ret;
+ }
+
+ /* Verify pixel clock value if any & inform user accordingly */
+ ret = clk_get_by_name(dev, "pxclk", &pxclk);
+ if (!ret) {
+ if (clk_get_rate(&pxclk) != priv->timing.pixelclock.typ)
+ printf("Warning: please adjust ltdc pixel clock\n");
+ }
+
+ /* TODO Below parameters are hard-coded for the moment... */
+ priv->l2bpp = VIDEO_BPP16;
+ priv->bg_col_argb = 0xFFFFFFFF; /* white no transparency */
+ priv->crop_x = 0;
+ priv->crop_y = 0;
+ priv->crop_w = priv->timing.hactive.typ;
+ priv->crop_h = priv->timing.vactive.typ;
+ priv->alpha = 0xFF;
+
+ debug("%s: %dx%d %dbpp frame buffer at 0x%lx\n", __func__,
+ priv->timing.hactive.typ, priv->timing.vactive.typ,
+ VNBITS(priv->l2bpp), uc_plat->base);
+ debug("%s: crop %d,%d %dx%d bg 0x%08x alpha %d\n", __func__,
+ priv->crop_x, priv->crop_y, priv->crop_w, priv->crop_h,
+ priv->bg_col_argb, priv->alpha);
+
+ /* Configure & start LTDC */
+ stm32_ltdc_set_mode(priv);
+ stm32_ltdc_set_layer1(priv, uc_plat->base);
+ stm32_ltdc_enable(priv);
+
+ uc_priv->xsize = priv->timing.hactive.typ;
+ uc_priv->ysize = priv->timing.vactive.typ;
+ uc_priv->bpix = priv->l2bpp;
+
+ video_set_flush_dcache(dev, true);
+
+ return 0;
+}
+
+static int stm32_ltdc_bind(struct udevice *dev)
+{
+ struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+
+ uc_plat->size = CONFIG_VIDEO_STM32_MAX_XRES *
+ CONFIG_VIDEO_STM32_MAX_YRES *
+ (CONFIG_VIDEO_STM32_MAX_BPP >> 3);
+ debug("%s: frame buffer max size %d bytes\n", __func__, uc_plat->size);
+
+ return 0;
+}
+
+static const struct udevice_id stm32_ltdc_ids[] = {
+ { .compatible = "st,stm32-ltdc" },
+ { }
+};
+
+U_BOOT_DRIVER(stm32_ltdc) = {
+ .name = "stm32_ltdc",
+ .id = UCLASS_VIDEO,
+ .of_match = stm32_ltdc_ids,
+ .probe = stm32_ltdc_probe,
+ .bind = stm32_ltdc_bind,
+ .priv_auto_alloc_size = sizeof(struct stm32_ltdc_priv),
+};