u-boot/drivers/video/stm32/stm32_ltdc.c
Patrick Delaunay 6cdeb323b8 video: stm32: stm32_ltdc: align framebuffer on 2MB
Align the framebuffer size on MMU_SECTION_SIZE in kernel, = max 2MB for
LPAE for armV7, to avoid issue with the simple frame buffer activation,
when U-Boot add a reserved memory in the kernel device tree to preserve
the splash screen until Linux driver initialization.

See Linux documentation for details:
Documentation/devicetree/bindings/display/simple-framebuffer.yaml

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
2021-11-30 16:43:28 +01:00

482 lines
15 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017-2018 STMicroelectronics - All Rights Reserved
* Author(s): Philippe Cornu <philippe.cornu@st.com> for STMicroelectronics.
* Yannick Fertre <yannick.fertre@st.com> for STMicroelectronics.
*/
#define LOG_CATEGORY UCLASS_VIDEO
#include <common.h>
#include <clk.h>
#include <display.h>
#include <dm.h>
#include <log.h>
#include <panel.h>
#include <reset.h>
#include <video.h>
#include <video_bridge.h>
#include <asm/io.h>
#include <dm/device-internal.h>
#include <dm/device_compat.h>
#include <linux/bitops.h>
struct stm32_ltdc_priv {
void __iomem *regs;
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 BF1_CA 0x400 /* Constant Alpha */
#define BF2_1PAXCA 0x007 /* 1 - (Pixel Alpha x Constant Alpha) */
#define BF2_1CA 0x005 /* 1 - 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_BPP32:
pf = PF_ARGB8888;
break;
case VIDEO_BPP8:
pf = PF_L8;
break;
case VIDEO_BPP1:
case VIDEO_BPP2:
case VIDEO_BPP4:
default:
log_warning("warning %dbpp not supported yet, %dbpp instead\n",
VNBITS(l2bpp), VNBITS(VIDEO_BPP16));
pf = PF_RGB565;
break;
}
log_debug("%d bpp -> ltdc pf %d\n", VNBITS(l2bpp), pf);
return (u32)pf;
}
static bool has_alpha(u32 fmt)
{
switch (fmt) {
case PF_ARGB8888:
case PF_ARGB1555:
case PF_ARGB4444:
case PF_AL44:
case PF_AL88:
return true;
case PF_RGB888:
case PF_RGB565:
case PF_L8:
default:
return false;
}
}
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,
struct display_timing *timings)
{
void __iomem *regs = priv->regs;
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 = timings->hsync_len.typ - 1;
vsync = timings->vsync_len.typ - 1;
acc_hbp = hsync + timings->hback_porch.typ;
acc_vbp = vsync + timings->vback_porch.typ;
acc_act_w = acc_hbp + timings->hactive.typ;
acc_act_h = acc_vbp + timings->vactive.typ;
total_w = acc_act_w + timings->hfront_porch.typ;
total_h = acc_act_h + timings->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);
setbits_le32(regs + LTDC_LIPCR, acc_act_h + 1);
/* Signal polarities */
val = 0;
log_debug("timing->flags 0x%08x\n", timings->flags);
if (timings->flags & DISPLAY_FLAGS_HSYNC_HIGH)
val |= GCR_HSPOL;
if (timings->flags & DISPLAY_FLAGS_VSYNC_HIGH)
val |= GCR_VSPOL;
if (timings->flags & DISPLAY_FLAGS_DE_HIGH)
val |= GCR_DEPOL;
if (timings->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;
u32 format;
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 */
format = stm32_ltdc_get_pixel_format(priv->l2bpp);
clrsetbits_le32(regs + LTDC_L1PFCR, LXPFCR_PF, format);
/* Constant alpha value */
clrsetbits_le32(regs + LTDC_L1CACR, LXCACR_CONSTA, priv->alpha);
/* Specifies the blending factors : with or without pixel alpha */
/* Manage hw-specific capabilities */
val = has_alpha(format) ? BF1_PAXCA | BF2_1PAXCA : BF1_CA | BF2_1CA;
/* Blending factors */
clrsetbits_le32(regs + LTDC_L1BFCR, LXBFCR_BF2 | LXBFCR_BF1, val);
/* 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_plat *uc_plat = dev_get_uclass_plat(dev);
struct video_priv *uc_priv = dev_get_uclass_priv(dev);
struct stm32_ltdc_priv *priv = dev_get_priv(dev);
struct udevice *bridge = NULL;
struct udevice *panel = NULL;
struct display_timing timings;
struct clk pclk;
struct reset_ctl rst;
int ret;
priv->regs = (void *)dev_read_addr(dev);
if ((fdt_addr_t)priv->regs == FDT_ADDR_T_NONE) {
dev_err(dev, "ltdc dt register address error\n");
return -EINVAL;
}
ret = clk_get_by_index(dev, 0, &pclk);
if (ret) {
dev_err(dev, "peripheral clock get error %d\n", ret);
return ret;
}
ret = clk_enable(&pclk);
if (ret) {
dev_err(dev, "peripheral clock enable error %d\n", ret);
return ret;
}
ret = uclass_first_device_err(UCLASS_PANEL, &panel);
if (ret) {
if (ret != -ENODEV)
dev_err(dev, "panel device error %d\n", ret);
return ret;
}
ret = panel_get_display_timing(panel, &timings);
if (ret) {
ret = ofnode_decode_display_timing(dev_ofnode(panel),
0, &timings);
if (ret) {
dev_err(dev, "decode display timing error %d\n", ret);
return ret;
}
}
ret = clk_set_rate(&pclk, timings.pixelclock.typ);
if (ret)
dev_warn(dev, "fail to set pixel clock %d hz\n",
timings.pixelclock.typ);
dev_dbg(dev, "Set pixel clock req %d hz get %ld hz\n",
timings.pixelclock.typ, clk_get_rate(&pclk));
ret = reset_get_by_index(dev, 0, &rst);
if (ret) {
dev_err(dev, "missing ltdc hardware reset\n");
return ret;
}
/* Reset */
reset_deassert(&rst);
if (IS_ENABLED(CONFIG_VIDEO_BRIDGE)) {
ret = uclass_get_device(UCLASS_VIDEO_BRIDGE, 0, &bridge);
if (ret)
dev_dbg(dev,
"No video bridge, or no backlight on bridge\n");
if (bridge) {
ret = video_bridge_attach(bridge);
if (ret) {
dev_err(bridge, "fail to attach bridge\n");
return ret;
}
}
}
/* 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 = timings.hactive.typ;
priv->crop_h = timings.vactive.typ;
priv->alpha = 0xFF;
dev_dbg(dev, "%dx%d %dbpp frame buffer at 0x%lx\n",
timings.hactive.typ, timings.vactive.typ,
VNBITS(priv->l2bpp), uc_plat->base);
dev_dbg(dev, "crop %d,%d %dx%d bg 0x%08x alpha %d\n",
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, &timings);
stm32_ltdc_set_layer1(priv, uc_plat->base);
stm32_ltdc_enable(priv);
uc_priv->xsize = timings.hactive.typ;
uc_priv->ysize = timings.vactive.typ;
uc_priv->bpix = priv->l2bpp;
if (!bridge) {
ret = panel_enable_backlight(panel);
if (ret) {
dev_err(dev, "panel %s enable backlight error %d\n",
panel->name, ret);
return ret;
}
} else if (IS_ENABLED(CONFIG_VIDEO_BRIDGE)) {
ret = video_bridge_set_backlight(bridge, 80);
if (ret) {
dev_err(dev, "fail to set backlight\n");
return ret;
}
}
video_set_flush_dcache(dev, true);
return 0;
}
static int stm32_ltdc_bind(struct udevice *dev)
{
struct video_uc_plat *uc_plat = dev_get_uclass_plat(dev);
uc_plat->size = CONFIG_VIDEO_STM32_MAX_XRES *
CONFIG_VIDEO_STM32_MAX_YRES *
(CONFIG_VIDEO_STM32_MAX_BPP >> 3);
/* align framebuffer on kernel MMU_SECTION_SIZE = max 2MB for LPAE */
uc_plat->align = SZ_2M;
dev_dbg(dev, "frame buffer max size %d bytes align %x\n",
uc_plat->size, uc_plat->align);
return 0;
}
static const struct udevice_id stm32_ltdc_ids[] = {
{ .compatible = "st,stm32-ltdc" },
{ }
};
U_BOOT_DRIVER(stm32_ltdc) = {
.name = "stm32_display",
.id = UCLASS_VIDEO,
.of_match = stm32_ltdc_ids,
.probe = stm32_ltdc_probe,
.bind = stm32_ltdc_bind,
.priv_auto = sizeof(struct stm32_ltdc_priv),
};