u-boot/drivers/video/imx/mxc_ipuv3_fb.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Code fixes:
 *
 * (C) Copyright 2025
 * Brian Ruley, GE HealthCare, brian.ruley@gehealthcare.com
 *
 * Porting to u-boot:
 *
 * (C) Copyright 2010
 * Stefano Babic, DENX Software Engineering, sbabic@denx.de
 *
 * MX51 Linux framebuffer:
 *
 * (C) Copyright 2004-2010 Freescale Semiconductor, Inc.
 */

#include "../videomodes.h"
#include "display.h"
#include "ipu.h"
#include "ipu_regs.h"
#include "mxcfb.h"
#include <asm/cache.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <asm/mach-imx/video.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/list.h>
#include <linux/string.h>
#include <log.h>
#include <panel.h>
#include <part.h>

#include <dm.h>
#include <dm/devres.h>
#include <video.h>

DECLARE_GLOBAL_DATA_PTR;

static int mxcfb_map_video_memory(struct fb_info *fbi);
static int mxcfb_unmap_video_memory(struct fb_info *fbi);

static struct fb_videomode const *gmode;
static u8 gdisp;
static u32 gpixfmt;

static void fb_videomode_to_var(struct fb_var_screeninfo *var,
				const struct fb_videomode *mode)
{
	var->xres = mode->xres;
	var->yres = mode->yres;
	var->xres_virtual = mode->xres;
	var->yres_virtual = mode->yres;
	var->xoffset = 0;
	var->yoffset = 0;
	var->pixclock = mode->pixclock;
	var->left_margin = mode->left_margin;
	var->right_margin = mode->right_margin;
	var->upper_margin = mode->upper_margin;
	var->lower_margin = mode->lower_margin;
	var->hsync_len = mode->hsync_len;
	var->vsync_len = mode->vsync_len;
	var->sync = mode->sync;
	var->vmode = mode->vmode & FB_VMODE_MASK;
}

struct ipuv3_video_priv {
	struct ipu_ctx *ctx;
	ulong regs;
};

/*
 * Structure containing the MXC specific framebuffer information.
 */
struct mxcfb_info {
	struct udevice *udev;
	int blank;
	ipu_channel_t ipu_ch;
	struct ipu_di_config *di;
	u32 ipu_di_pix_fmt;
	unsigned char overlay;
	unsigned char alpha_chan_en;
	dma_addr_t alpha_phy_addr0;
	dma_addr_t alpha_phy_addr1;
	void *alpha_virt_addr0;
	void *alpha_virt_addr1;
	u32 alpha_mem_len;
	u32 cur_ipu_buf;
	u32 cur_ipu_alpha_buf;

	u32 pseudo_palette[16];

	struct ipu_ctx *ctx;
};

enum { BOTH_ON, SRC_ON, TGT_ON, BOTH_OFF };

static unsigned long default_bpp = 16;
static unsigned char g_dp_in_use;
static struct fb_info *mxcfb_info[3];
static int ext_clk_used;

static u32 bpp_to_pixfmt(struct fb_info *fbi)
{
	u32 pixfmt = 0;

	debug("bpp_to_pixfmt: %d\n", fbi->var.bits_per_pixel);

	if (fbi->var.nonstd)
		return fbi->var.nonstd;

	switch (fbi->var.bits_per_pixel) {
	case 24:
		pixfmt = IPU_PIX_FMT_BGR24;
		break;
	case 32:
		pixfmt = IPU_PIX_FMT_BGR32;
		break;
	case 16:
		pixfmt = IPU_PIX_FMT_RGB565;
		break;
	}
	return pixfmt;
}

static int setup_disp_channel1(struct fb_info *fbi)
{
	ipu_channel_params_t params;
	struct mxcfb_info *mxc_fbi = (struct mxcfb_info *)fbi->par;

	memset(&params, 0, sizeof(params));
	params.mem_dp_bg_sync.di = mxc_fbi->di->disp;

	debug("%s called\n", __func__);
	/*
	 * Assuming interlaced means yuv output, below setting also
	 * valid for mem_dc_sync. FG should have the same vmode as BG.
	 */
	if (fbi->var.vmode & FB_VMODE_INTERLACED) {
		params.mem_dp_bg_sync.interlaced = 1;
		params.mem_dp_bg_sync.out_pixel_fmt = IPU_PIX_FMT_YUV444;
	} else if (mxc_fbi->ipu_di_pix_fmt) {
		params.mem_dp_bg_sync.out_pixel_fmt = mxc_fbi->ipu_di_pix_fmt;
	} else {
		params.mem_dp_bg_sync.out_pixel_fmt = IPU_PIX_FMT_RGB666;
	}
	params.mem_dp_bg_sync.in_pixel_fmt = bpp_to_pixfmt(fbi);
	if (mxc_fbi->alpha_chan_en)
		params.mem_dp_bg_sync.alpha_chan_en = 1;

	return ipu_init_channel(mxc_fbi->ctx, mxc_fbi->ipu_ch, &params);
}

static int setup_disp_channel2(struct fb_info *fbi)
{
	int retval = 0;
	struct mxcfb_info *mxc_fbi = (struct mxcfb_info *)fbi->par;

	mxc_fbi->cur_ipu_buf = 1;
	if (mxc_fbi->alpha_chan_en)
		mxc_fbi->cur_ipu_alpha_buf = 1;

	fbi->var.xoffset = fbi->var.yoffset = 0;

	debug("%s: %x %d %d %d %lx %lx\n", __func__, mxc_fbi->ipu_ch,
	      fbi->var.xres, fbi->var.yres, fbi->fix.line_length,
	      fbi->fix.smem_start,
	      fbi->fix.smem_start + (fbi->fix.line_length * fbi->var.yres));

	retval = ipu_init_channel_buffer(
		mxc_fbi->ipu_ch, IPU_INPUT_BUFFER, bpp_to_pixfmt(fbi),
		fbi->var.xres, fbi->var.yres, fbi->fix.line_length,
		fbi->fix.smem_start + (fbi->fix.line_length * fbi->var.yres),
		fbi->fix.smem_start, 0, 0);
	if (retval)
		printf("ipu_init_channel_buffer error %d\n", retval);

	return retval;
}

/*
 * Set framebuffer parameters and change the operating mode.
 *
 * @param	info	 framebuffer information pointer
 */
static int mxcfb_set_par(struct fb_info *fbi)
{
	int retval = 0;
	u32 mem_len;
	ipu_di_signal_cfg_t sig_cfg;
	struct mxcfb_info *mxc_fbi = (struct mxcfb_info *)fbi->par;
	u32 out_pixel_fmt;

	ipu_disable_channel(mxc_fbi->ctx, mxc_fbi->ipu_ch);
	ipu_uninit_channel(mxc_fbi->ctx, mxc_fbi->ipu_ch);

	mem_len = fbi->var.yres_virtual * fbi->fix.line_length;
	if (!fbi->fix.smem_start || (mem_len > fbi->fix.smem_len)) {
		if (fbi->fix.smem_start)
			mxcfb_unmap_video_memory(fbi);

		if (mxcfb_map_video_memory(fbi) < 0)
			return -ENOMEM;
	}

	setup_disp_channel1(fbi);

	memset(&sig_cfg, 0, sizeof(sig_cfg));
	if (fbi->var.vmode & FB_VMODE_INTERLACED) {
		sig_cfg.interlaced = 1;
		out_pixel_fmt = IPU_PIX_FMT_YUV444;
	} else {
		if (mxc_fbi->ipu_di_pix_fmt)
			out_pixel_fmt = mxc_fbi->ipu_di_pix_fmt;
		else
			out_pixel_fmt = IPU_PIX_FMT_RGB666;
	}
	if (fbi->var.vmode & FB_VMODE_ODD_FLD_FIRST) /* PAL */
		sig_cfg.odd_field_first = 1;
	if ((fbi->var.sync & FB_SYNC_EXT) || ext_clk_used)
		sig_cfg.ext_clk = 1;
	if (fbi->var.sync & FB_SYNC_HOR_HIGH_ACT)
		sig_cfg.hsync_pol = 1;
	if (fbi->var.sync & FB_SYNC_VERT_HIGH_ACT)
		sig_cfg.vsync_pol = 1;
	if (!(fbi->var.sync & FB_SYNC_CLK_LAT_FALL))
		sig_cfg.clk_pol = 1;
	if (fbi->var.sync & FB_SYNC_DATA_INVERT)
		sig_cfg.data_pol = 1;
	if (!(fbi->var.sync & FB_SYNC_OE_LOW_ACT))
		sig_cfg.enable_pol = 1;
	if (fbi->var.sync & FB_SYNC_CLK_IDLE_EN)
		sig_cfg.clkidle_en = 1;

	debug("pixclock = %lu Hz\n", PICOS2KHZ(fbi->var.pixclock) * 1000UL);

	mxc_fbi->di->pixel_clk_rate = (PICOS2KHZ(fbi->var.pixclock)) * 1000UL;
	mxc_fbi->di->pixel_fmt = out_pixel_fmt;
	mxc_fbi->di->width = fbi->var.xres;
	mxc_fbi->di->height = fbi->var.yres;
	mxc_fbi->di->h_start_width = fbi->var.left_margin;
	mxc_fbi->di->h_sync_width = fbi->var.hsync_len;
	mxc_fbi->di->h_end_width = fbi->var.right_margin;
	mxc_fbi->di->v_start_width = fbi->var.upper_margin;
	mxc_fbi->di->v_sync_width = fbi->var.vsync_len;
	mxc_fbi->di->v_end_width = fbi->var.lower_margin;
	mxc_fbi->di->v_to_h_sync = 0;

	if (ipu_init_sync_panel(mxc_fbi->di, sig_cfg) != 0) {
		puts("mxcfb: Error initializing panel.\n");
		return -EINVAL;
	}

	retval = setup_disp_channel2(fbi);
	if (retval)
		return retval;

	if (mxc_fbi->blank == FB_BLANK_UNBLANK)
		ipu_enable_channel(mxc_fbi->ctx, mxc_fbi->ipu_ch);

	return retval;
}

/*
 * Check framebuffer variable parameters and adjust to valid values.
 *
 * @param	var	 framebuffer variable parameters
 *
 * @param	info	 framebuffer information pointer
 */
static int mxcfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
	u32 vtotal;
	u32 htotal;

	if (var->xres_virtual < var->xres)
		var->xres_virtual = var->xres;
	if (var->yres_virtual < var->yres)
		var->yres_virtual = var->yres;

	if ((var->bits_per_pixel != 32) && (var->bits_per_pixel != 24) &&
	    (var->bits_per_pixel != 16) && (var->bits_per_pixel != 8))
		var->bits_per_pixel = default_bpp;

	switch (var->bits_per_pixel) {
	case 8:
		var->red.length = 3;
		var->red.offset = 5;
		var->red.msb_right = 0;

		var->green.length = 3;
		var->green.offset = 2;
		var->green.msb_right = 0;

		var->blue.length = 2;
		var->blue.offset = 0;
		var->blue.msb_right = 0;

		var->transp.length = 0;
		var->transp.offset = 0;
		var->transp.msb_right = 0;
		break;
	case 16:
		var->red.length = 5;
		var->red.offset = 11;
		var->red.msb_right = 0;

		var->green.length = 6;
		var->green.offset = 5;
		var->green.msb_right = 0;

		var->blue.length = 5;
		var->blue.offset = 0;
		var->blue.msb_right = 0;

		var->transp.length = 0;
		var->transp.offset = 0;
		var->transp.msb_right = 0;
		break;
	case 24:
		var->red.length = 8;
		var->red.offset = 16;
		var->red.msb_right = 0;

		var->green.length = 8;
		var->green.offset = 8;
		var->green.msb_right = 0;

		var->blue.length = 8;
		var->blue.offset = 0;
		var->blue.msb_right = 0;

		var->transp.length = 0;
		var->transp.offset = 0;
		var->transp.msb_right = 0;
		break;
	case 32:
		var->red.length = 8;
		var->red.offset = 16;
		var->red.msb_right = 0;

		var->green.length = 8;
		var->green.offset = 8;
		var->green.msb_right = 0;

		var->blue.length = 8;
		var->blue.offset = 0;
		var->blue.msb_right = 0;

		var->transp.length = 8;
		var->transp.offset = 24;
		var->transp.msb_right = 0;
		break;
	}

	if (var->pixclock < 1000) {
		htotal = var->xres + var->right_margin + var->hsync_len +
			 var->left_margin;
		vtotal = var->yres + var->lower_margin + var->vsync_len +
			 var->upper_margin;
		var->pixclock = (vtotal * htotal * 6UL) / 100UL;
		var->pixclock = KHZ2PICOS(var->pixclock);
		printf("pixclock set for 60Hz refresh = %u ps\n",
		       var->pixclock);
	}

	var->height = -1;
	var->width = -1;
	var->grayscale = 0;

	return 0;
}

static int mxcfb_map_video_memory(struct fb_info *fbi)
{
	struct mxcfb_info *mxc_fbi = (struct mxcfb_info *)fbi->par;
	struct video_uc_plat *plat = dev_get_uclass_plat(mxc_fbi->udev);

	if (fbi->fix.smem_len < fbi->var.yres_virtual * fbi->fix.line_length) {
		fbi->fix.smem_len =
			fbi->var.yres_virtual * fbi->fix.line_length;
	}
	fbi->fix.smem_len = roundup(fbi->fix.smem_len, ARCH_DMA_MINALIGN);

	fbi->screen_base = (char *)plat->base;

	fbi->fix.smem_start = (unsigned long)fbi->screen_base;
	if (fbi->screen_base == 0) {
		puts("Unable to allocate framebuffer memory\n");
		fbi->fix.smem_len = 0;
		fbi->fix.smem_start = 0;
		return -EBUSY;
	}

	debug("allocated fb @ paddr=0x%08X, size=%d.\n",
	      (u32)fbi->fix.smem_start, fbi->fix.smem_len);

	fbi->screen_size = fbi->fix.smem_len;

	/* Clear the screen */
	memset((char *)fbi->screen_base, 0, fbi->fix.smem_len);

	return 0;
}

static int mxcfb_unmap_video_memory(struct fb_info *fbi)
{
	fbi->screen_base = 0;
	fbi->fix.smem_start = 0;
	fbi->fix.smem_len = 0;
	return 0;
}

/*
 * Initializes the framebuffer information pointer. After allocating
 * sufficient memory for the framebuffer structure, the fields are
 * filled with custom information passed in from the configurable
 * structures.	This includes information such as bits per pixel,
 * color maps, screen width/height and RGBA offsets.
 *
 * @param	dev	The device structure for the IPU passed in by the
 *			driver framework.
 *
 * Return:	Framebuffer structure initialized with our information
 */
static struct fb_info *mxcfb_init_fbinfo(struct udevice *dev)
{
#define BYTES_PER_LONG 4
#define PADDING (BYTES_PER_LONG - (sizeof(struct fb_info) % BYTES_PER_LONG))
	struct fb_info *fbi;
	struct mxcfb_info *mxcfbi;
	char *p;
	int size = sizeof(struct mxcfb_info) + PADDING + sizeof(struct fb_info);

	debug("%s: %d %d %d %d\n", __func__, PADDING, size,
	      sizeof(struct mxcfb_info), sizeof(struct fb_info));
	/*
	 * Allocate sufficient memory for the fb structure
	 */
	p = devm_kzalloc(dev, size, GFP_KERNEL);
	if (!p)
		return NULL;

	fbi = (struct fb_info *)p;
	fbi->par = p + sizeof(struct fb_info) + PADDING;

	mxcfbi = (struct mxcfb_info *)fbi->par;
	debug("Framebuffer structures at: fbi=0x%x mxcfbi=0x%x\n",
	      (unsigned int)fbi, (unsigned int)mxcfbi);

	fbi->var.activate = FB_ACTIVATE_NOW;

	fbi->flags = FBINFO_FLAG_DEFAULT;
	fbi->pseudo_palette = mxcfbi->pseudo_palette;

	return fbi;
}

/*
 * Probe routine for the framebuffer driver. It is called during the
 * driver binding process. The following functions are performed in
 * this routine: Framebuffer initialization, Memory allocation and
 * mapping, Framebuffer registration, IPU initialization.
 *
 * Return:	Appropriate error code to the kernel common code
 */
static int mxcfb_probe(struct udevice *dev, u32 interface_pix_fmt, u8 disp,
		       struct fb_videomode const *mode)
{
	struct ipuv3_video_priv *ipu_priv = dev_get_priv(dev);
	struct ipu_ctx *ctx = ipu_priv->ctx;
	struct fb_info *fbi;
	struct mxcfb_info *mxcfbi;

	/*
	 * Initialize FB structures
	 */
	fbi = mxcfb_init_fbinfo(dev);
	if (!fbi)
		return -ENOMEM;

	mxcfbi = (struct mxcfb_info *)fbi->par;

	if (!g_dp_in_use) {
		mxcfbi->ipu_ch = MEM_BG_SYNC;
		mxcfbi->blank = FB_BLANK_UNBLANK;
	} else {
		mxcfbi->ipu_ch = MEM_DC_SYNC;
		mxcfbi->blank = FB_BLANK_POWERDOWN;
	}

	mxcfbi->di = devm_kzalloc(ctx->dev, sizeof(*mxcfbi->di), GFP_KERNEL);
	if (!mxcfbi->di)
		return -ENOMEM;

	mxcfbi->di->disp = disp;
	mxcfbi->di->ctx = ctx;
	mxcfbi->ctx = ctx;
	mxcfbi->udev = dev;

	if (!ipu_clk_enabled(ctx))
		clk_enable(ctx->ipu_clk);

	ipu_disp_set_global_alpha(mxcfbi->ipu_ch, 1, 0x80);
	ipu_disp_set_color_key(mxcfbi->ipu_ch, 0, 0);

	g_dp_in_use = 1;

	mxcfb_info[mxcfbi->di->disp] = fbi;

	/* Need dummy values until real panel is configured */

	mxcfbi->ipu_di_pix_fmt = interface_pix_fmt;
	fb_videomode_to_var(&fbi->var, mode);
	fbi->var.bits_per_pixel = 16;
	fbi->fix.line_length =
		fbi->var.xres_virtual * (fbi->var.bits_per_pixel / 8);
	fbi->fix.smem_len = fbi->var.yres_virtual * fbi->fix.line_length;

	mxcfb_check_var(&fbi->var, fbi);

	/* Default Y virtual size is 2x panel size */
	fbi->var.yres_virtual = fbi->var.yres * 2;

	/* allocate fb first */
	if (mxcfb_map_video_memory(fbi) < 0)
		return -ENOMEM;

	mxcfb_set_par(fbi);

#ifdef DEBUG
	ipu_dump_registers();
#endif

	return 0;
}

void ipuv3_fb_shutdown(struct udevice *dev)
{
	int i;
	struct ipu_stat *stat = (struct ipu_stat *)IPU_STAT;
	struct ipuv3_video_priv *ipu_priv = dev_get_priv(dev);
	struct ipu_ctx *ctx = ipu_priv->ctx;

	if (!ipu_clk_enabled(ctx))
		return;

	for (i = 0; i < ARRAY_SIZE(mxcfb_info); i++) {
		struct fb_info *fbi = mxcfb_info[i];
		if (fbi) {
			struct mxcfb_info *mxc_fbi = fbi->par;
			ipu_disable_channel(ctx, mxc_fbi->ipu_ch);
			ipu_uninit_channel(ctx, mxc_fbi->ipu_ch);
		}
	}
	for (i = 0; i < ARRAY_SIZE(stat->int_stat); i++) {
		__raw_writel(__raw_readl(&stat->int_stat[i]),
			     &stat->int_stat[i]);
	}
}

int ipuv3_fb_init(struct fb_videomode const *mode, u8 disp, u32 pixfmt)
{
	gmode = mode;
	gdisp = disp;
	gpixfmt = pixfmt;

	return 0;
}

enum {
	/* Maximum display size we support */
	LCD_MAX_WIDTH = 1920,
	LCD_MAX_HEIGHT = 1080,
	LCD_MAX_LOG2_BPP = VIDEO_BPP16,
};

static int ipuv3_video_probe(struct udevice *dev)
{
	struct video_uc_plat *plat = dev_get_uclass_plat(dev);
	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
	struct ipuv3_video_priv *ipu_priv = dev_get_priv(dev);
#if defined(CONFIG_DISPLAY)
	struct udevice *disp_dev;
#endif
	struct ipu_ctx *ctx;
	u32 fb_start, fb_end;
	int ret;

	debug("%s() plat: base 0x%lx, size 0x%x\n", __func__, plat->base,
	      plat->size);

	ctx = ipu_probe(dev);
	if (IS_ERR(ctx))
		return PTR_ERR(ctx);

	ipu_priv->ctx = ctx;

	ret = ipu_displays_init();
	if (ret < 0)
		return ret;

	ret = mxcfb_probe(dev, gpixfmt, gdisp, gmode);
	if (ret < 0)
		return ret;

#if defined(CONFIG_DISPLAY)
	ret = uclass_first_device_err(UCLASS_DISPLAY, &disp_dev);
	if (!ret)
		ret = display_enable(disp_dev, 16, NULL);
	if (ret < 0)
		return ret;
#endif
	if (IS_ENABLED(CONFIG_PANEL)) {
		struct udevice *panel_dev;

		ret = uclass_get_device(UCLASS_PANEL, 0, &panel_dev);
		if (panel_dev)
			panel_enable_backlight(panel_dev);
	}

	uc_priv->xsize = gmode->xres;
	uc_priv->ysize = gmode->yres;
	uc_priv->bpix = LCD_MAX_LOG2_BPP;

	/* Enable dcache for the frame buffer */
	fb_start = plat->base & ~(MMU_SECTION_SIZE - 1);
	fb_end = plat->base + plat->size;
	fb_end = ALIGN(fb_end, 1 << MMU_SECTION_SHIFT);
	mmu_set_region_dcache_behaviour(fb_start, fb_end - fb_start,
					DCACHE_WRITEBACK);
	video_set_flush_dcache(dev, true);

	return 0;
}

static int ipuv3_video_bind(struct udevice *dev)
{
	struct video_uc_plat *plat = dev_get_uclass_plat(dev);

	plat->size = LCD_MAX_WIDTH * LCD_MAX_HEIGHT * (1 << VIDEO_BPP32) / 8;

	return 0;
}

static const struct udevice_id ipuv3_video_ids[] = {
#ifdef CONFIG_ARCH_MX6
	{ .compatible = "fsl,imx6q-ipu" },
#endif
#ifdef CONFIG_ARCH_MX5
	{ .compatible = "fsl,imx53-ipu" },
#endif
	{}
};

U_BOOT_DRIVER(fsl_imx6q_ipu) = {
	.name = "fsl_imx6q_ipu",
	.id = UCLASS_VIDEO,
	.of_match = ipuv3_video_ids,
	.bind = ipuv3_video_bind,
	.probe = ipuv3_video_probe,
	.priv_auto = sizeof(struct ipuv3_video_priv),
	.flags = DM_FLAG_PRE_RELOC,
};