[PATCH 10/11] Add a video driver for S3C2440 bases platforms

Juergen Beisert jbe at pengutronix.de
Fri Nov 19 07:51:02 EST 2010


From: Juergen Beisert <juergen at kreuzholzen.de>

Signed-off-by: Juergen Beisert <juergen at kreuzholzen.de>
---
 arch/arm/mach-s3c24xx/include/mach/fb.h |   40 +++
 drivers/video/Kconfig                   |    6 +
 drivers/video/Makefile                  |    1 +
 drivers/video/s3c.c                     |  474 +++++++++++++++++++++++++++++++
 4 files changed, 521 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/mach-s3c24xx/include/mach/fb.h
 create mode 100644 drivers/video/s3c.c

diff --git a/arch/arm/mach-s3c24xx/include/mach/fb.h b/arch/arm/mach-s3c24xx/include/mach/fb.h
new file mode 100644
index 0000000..eec6164
--- /dev/null
+++ b/arch/arm/mach-s3c24xx/include/mach/fb.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2010 Juergen Beisert
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+
+#ifndef __MACH_FB_H_
+# define __MACH_FB_H_
+
+#include <fb.h>
+
+struct s3c_fb_platform_data {
+
+	const struct fb_videomode *mode_list;
+	unsigned mode_cnt;
+
+	int passive_display;	/**< enable support for STN or CSTN displays */
+
+	void *framebuffer;	/**< force framebuffer base address */
+	unsigned size;		/**< force framebuffer size */
+
+	/** hook to enable backlight and stuff */
+	void (*enable)(int);
+};
+
+#endif /* __MACH_FB_H_ */
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index b600444..f43c100 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -30,4 +30,10 @@ config DRIVER_VIDEO_IMX_IPU
 	  Add support for the IPU framebuffer device found on
 	  i.MX31 and i.MX35 CPUs.
 
+config S3C_VIDEO
+	bool "S3C244x framebuffer driver"
+	depends on ARCH_S3C24xx
+	help
+	  Add support for the S3C244x LCD controller.
+
 endif
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index 179f0c4..4287fc8 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_VIDEO) += fb.o
 
 obj-$(CONFIG_DRIVER_VIDEO_IMX) += imx.o
 obj-$(CONFIG_DRIVER_VIDEO_IMX_IPU) += imx-ipu-fb.o
+obj-$(CONFIG_S3C_VIDEO) += s3c.o
diff --git a/drivers/video/s3c.c b/drivers/video/s3c.c
new file mode 100644
index 0000000..c831ebd
--- /dev/null
+++ b/drivers/video/s3c.c
@@ -0,0 +1,474 @@
+/*
+ * Copyright (C) 2010 Juergen Beisert
+ *
+ * This driver is based on a patch found in the web:
+ * (C) Copyright 2006 by OpenMoko, Inc.
+ * Author: Harald Welte <laforge at openmoko.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <common.h>
+#include <init.h>
+#include <fb.h>
+#include <driver.h>
+#include <malloc.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <mach/gpio.h>
+#include <mach/s3c24xx-generic.h>
+#include <mach/s3c24x0-clocks.h>
+#include <mach/fb.h>
+
+#define LCDCON1 0x00
+# define PNRMODE(x) (((x) & 3) << 5)
+# define BPPMODE(x) (((x) & 0xf) << 1)
+# define SET_CLKVAL(x) (((x) & 0x3ff) << 8)
+# define GET_CLKVAL(x) (((x) >> 8) & 0x3ff)
+# define ENVID (1 << 0)
+
+#define LCDCON2 0x04
+# define SET_VBPD(x) (((x) & 0xff) << 24)
+# define SET_LINEVAL(x) (((x) & 0x3ff) << 14)
+# define SET_VFPD(x) (((x) & 0xff) << 6)
+# define SET_VSPW(x) ((x) & 0x3f)
+
+#define LCDCON3 0x08
+# define SET_HBPD(x) (((x) & 0x7f) << 19)
+# define SET_HOZVAL(x) (((x) & 0x7ff) << 8)
+# define SET_HFPD(x) ((x) & 0xff)
+
+#define LCDCON4 0x0c
+# define SET_HSPW(x) ((x) & 0xff)
+
+#define LCDCON5 0x10
+# define BPP24BL (1 << 12)
+# define FRM565 (1 << 11)
+# define INV_CLK (1 << 10)
+# define INV_HS (1 << 9)
+# define INV_VS (1 << 8)
+# define INV_DTA (1 << 7)
+# define INV_DE (1 << 6)
+# define INV_PWREN (1 << 5)
+# define INV_LEND (1 << 4)	/* FIXME */
+# define ENA_PWREN (1 << 3)
+# define ENA_LEND (1 << 2)	/* FIXME */
+# define BSWP (1 << 1)
+# define HWSWP (1 << 0)
+
+#define LCDSADDR1 0x14
+# define SET_LCDBANK(x) (((x) & 0x1ff) << 21)
+# define GET_LCDBANK(x) (((x) >> 21) & 0x1ff)
+# define SET_LCDBASEU(x) ((x) & 0x1fffff)
+# define GET_LCDBASEU(x) ((x) & 0x1fffff)
+
+#define LCDSADDR2 0x18
+# define SET_LCDBASEL(x) ((x) & 0x1fffff)
+# define GET_LCDBASEL(x) ((x) & 0x1fffff)
+
+#define LCDSADDR3 0x1c
+# define SET_OFFSIZE(x) (((x) & 0x7ff) << 11)
+# define GET_OFFSIZE(x) (((x) >> 11) & 0x7ff)
+# define SET_PAGE_WIDTH(x) ((x) & 0x3ff)
+# define GET_PAGE_WIDTH(x) ((x) & 0x3ff)
+
+#define RED_LUT 0x20
+#define GREEN_LUT 0x24
+#define BLUE_LUT 0x28
+
+#define DITHMODE 0x4c
+
+#define TPAL 0x50
+
+#define LCDINTPND 0x54
+
+#define LCDSRCPND 0x58
+
+#define LCDINTMSK 0x5c
+# define FIWSEL (1 << 2)
+
+#define TCONSEL 0x60
+
+#define RED 0
+#define GREEN 1
+#define BLUE 2
+#define TRANSP 3
+
+struct s3cfb_host {
+	struct fb_host fb_data;
+	struct device_d *hw_dev;
+	struct s3c_fb_platform_data *pdata; /* shortcut to hw_dev->platform_data */
+	void __iomem *base;
+};
+
+#define fb_info_to_s3cfb_host(x) ((struct s3cfb_host*)((x)->host))
+
+/* the RGB565 true colour mode */
+static const struct fb_bitfield def_rgb565[] = {
+	[RED] = {
+		.offset = 11,
+		.length = 5,
+	},
+	[GREEN] = {
+		.offset = 5,
+		.length = 6,
+	},
+	[BLUE] = {
+		.offset = 0,
+		.length = 5,
+	},
+	[TRANSP] = {	/* no support for transparency */
+		.length = 0,
+	}
+};
+
+/* the RGB888 true colour mode */
+static const struct fb_bitfield def_rgb888[] = {
+	[RED] = {
+		.offset = 16,
+		.length = 8,
+	},
+	[GREEN] = {
+		.offset = 8,
+		.length = 8,
+	},
+	[BLUE] = {
+		.offset = 0,
+		.length = 8,
+	},
+	[TRANSP] = {	/* no support for transparency */
+		.length = 0,
+	}
+};
+
+/**
+ * @param fb_info Framebuffer information
+ */
+static void s3cfb_enable_controller(struct fb_info *fb_info)
+{
+	struct s3cfb_host *fbh = fb_info_to_s3cfb_host(fb_info);
+	struct s3c_fb_platform_data *pdata = fbh->pdata;
+	uint32_t con1;
+
+	con1 = readl(fbh->base + LCDCON1);
+
+	con1 |= ENVID;
+
+	writel(con1, fbh->base + LCDCON1);
+
+	if (pdata->enable)
+		pdata->enable(1);
+}
+
+/**
+ * @param fb_info Framebuffer information
+ */
+static void s3cfb_disable_controller(struct fb_info *fb_info)
+{
+	struct s3cfb_host *fbh = fb_info_to_s3cfb_host(fb_info);
+	struct s3c_fb_platform_data *pdata = fbh->pdata;
+	uint32_t con1;
+
+	if (pdata->enable)
+		pdata->enable(0);
+
+	con1 = readl(fbh->base + LCDCON1);
+
+	con1 &= ~ENVID;
+
+	writel(con1, fbh->base + LCDCON1);
+}
+
+/**
+ * Framebuffer memory management
+ * @param fb_info Framebuffer information
+ * @param size Requested framebuffer size in bytes
+ * @return 0 on success
+ *
+ * If the user forces a fixed memory location, try to map the framebuffer into
+ * it. If it does not match, report an error. If no fixed memory location
+ * exists do memory allocation in a dynamic manner.
+ */
+static int s3cfb_memory_mmgt(struct fb_info *fb_info, unsigned size)
+{
+	struct s3cfb_host *fbh = fb_info_to_s3cfb_host(fb_info);
+	struct s3c_fb_platform_data *pdata = fbh->pdata;
+
+	if (pdata->framebuffer != NULL) {
+		/* fixed memory location */
+		if (pdata->size < size)
+			return -EINVAL;
+		fb_info->fb_dev.map_base = (resource_size_t)pdata->framebuffer;
+		fb_info->fb_dev.size = size;
+	} else {
+		/* dynamic memory location */
+		if ((fb_info->fb_dev.size < size) &&
+				(fb_info->fb_dev.size != 0)) {
+			free((void*)fb_info->fb_dev.map_base);
+			fb_info->fb_dev.map_base = 0;
+			fb_info->fb_dev.size = 0;
+		}
+		if (fb_info->fb_dev.size == 0) {
+			/* allocate more space on platform request */
+			if (pdata->size > size)
+				size = pdata->size;
+			fb_info->fb_dev.map_base =
+					(resource_size_t)xzalloc(size);
+			fb_info->fb_dev.size = size;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * Prepare the video hardware for a specified video mode
+ * @param fb_info Framebuffer information
+ * @param mode The video mode description to setup
+ * @return 0 on success
+ */
+static int s3cfb_initialize_mode(struct fb_info *fb_info,
+				const struct fb_videomode *mode)
+{
+	struct s3cfb_host *fbh = fb_info_to_s3cfb_host(fb_info);
+	struct s3c_fb_platform_data *pdata = fbh->pdata;
+	unsigned size, hclk, div;
+	int rc;
+	uint32_t con1, con2, con3, con4, con5 = 0;
+
+	if (pdata->passive_display != 0) {
+		dev_err(fbh->hw_dev,
+			"Passive displays are currently not supported\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * we need at least this amount of memory for the framebuffer
+	 */
+	size = mode->xres * mode->yres * (fb_info->bits_per_pixel >> 3);
+
+	rc = s3cfb_memory_mmgt(fb_info, size);
+	if (rc != 0) {
+		dev_err(fbh->hw_dev, "Cannot allocate framebuffer memory\n");
+		return rc;
+	}
+
+	/* its useful to enable the unit's clock */
+	s3c244x_mod_clock(CLK_LCDC, 1);
+
+	/* ensure video output is _off_ */
+	writel(0x00000000, fbh->base + LCDCON1);
+
+	hclk = s3c24xx_get_hclk() / 1000U;	/* hclk in kHz */
+	div = hclk / PICOS2KHZ(mode->pixclock);
+	if (div < 3)
+		div  = 3;
+	/* pixel clock is: (hclk) / ((div + 1) * 2) */
+	div += 1;
+	div >>= 1;
+	div -= 1;
+
+	con1 = PNRMODE(3) | SET_CLKVAL(div);	/* PNRMODE=3 is TFT */
+
+	switch (fb_info->bits_per_pixel) {
+#if 0
+	/** @todo S3C2440: Add CLUT based videomodes */
+	case 1:
+		con1 |= BPPMODE(8);
+		break;
+	case 2:
+		con1 |= BPPMODE(9);
+		break;
+	case 4:
+		con1 |= BPPMODE(10);
+		break;
+	case 8:
+		con1 |= BPPMODE(11);
+		break;
+#endif
+	case 16:
+		con1 |= BPPMODE(12);
+		con5 |= FRM565;
+		fb_info->red = def_rgb565[RED];
+		fb_info->green = def_rgb565[GREEN];
+		fb_info->blue = def_rgb565[BLUE];
+		fb_info->transp =  def_rgb565[TRANSP];
+		break;
+	case 24:
+		con1 |= BPPMODE(13);
+		/** @todo S3C2440: Define the correct byte order
+		 * for 24 bpp in memory (BPP24BL)
+		 */
+		con5 |= BPP24BL;
+		fb_info->red = def_rgb888[RED];
+		fb_info->green = def_rgb888[GREEN];
+		fb_info->blue = def_rgb888[BLUE];
+		fb_info->transp =  def_rgb888[TRANSP];
+		break;
+	default:
+		dev_err(fbh->hw_dev, "Invalid bits per pixel value: %u\n",
+			fb_info->bits_per_pixel);
+		return -EINVAL;
+	}
+
+	/* 'normal' in register description means positive logic */
+	if (!(mode->sync & FB_SYNC_HOR_HIGH_ACT))
+		con5 |= INV_HS;
+	if (!(mode->sync & FB_SYNC_VERT_HIGH_ACT))
+		con5 |= INV_VS;
+	if (!(mode->sync & FB_SYNC_DE_HIGH_ACT))
+		con5 |= INV_DE;
+	if (mode->sync & FB_SYNC_CLK_INVERT)
+		con5 |= INV_CLK; /* display should latch at the rising edge */
+	if (mode->sync & FB_SYNC_SWAP_RGB)
+		con5 |= HWSWP;
+
+	/** @todo S3C2440: LCD power enable via platform data */
+
+	/* vertical timing */
+	con2 = SET_VBPD(mode->upper_margin - 1) |
+		SET_LINEVAL(mode->yres - 1) |
+		SET_VFPD(mode->lower_margin - 1) |
+		SET_VSPW(mode->vsync_len - 1);
+
+	/* horizontal timing */
+	con3 = SET_HBPD(mode->left_margin - 1) |
+		SET_HOZVAL(mode->xres - 1) |
+		SET_HFPD(mode->right_margin - 1);
+	con4 = SET_HSPW(mode->hsync_len - 1);
+
+	/* basic timing setup */
+	writel(con1, fbh->base + LCDCON1);
+	writel(con2, fbh->base + LCDCON2);
+	writel(con3, fbh->base + LCDCON3);
+	writel(con4, fbh->base + LCDCON4);
+	writel(con5, fbh->base + LCDCON5);
+
+	/* framebuffer memory setup */
+	writel(((uint32_t)fb_info->fb_dev.map_base) >> 1,
+		fbh->base + LCDSADDR1);
+
+	writel(SET_LCDBASEL(((uint32_t)fb_info->fb_dev.map_base + size) >> 1),
+		fbh->base + LCDSADDR2);
+
+	writel(SET_OFFSIZE(0) |
+		SET_PAGE_WIDTH((mode->xres * fb_info->bits_per_pixel) >> 4),
+		fbh->base + LCDSADDR3);
+
+	writel(FIWSEL, fbh->base + LCDINTMSK);
+
+	return 0;
+}
+
+/**
+ * Print some information about the current hardware state
+ * @param hw_dev S3C video device
+ */
+#ifdef CONFIG_VIDEO_INFO_VERBOSE
+static void s3cfb_info(struct device_d *hw_dev)
+{
+	uint32_t con1, addr1, addr2, addr3;
+
+	con1 = readl(hw_dev->map_base + LCDCON1);
+	addr1 = readl(hw_dev->map_base + LCDSADDR1);
+	addr2 = readl(hw_dev->map_base + LCDSADDR2);
+	addr3 = readl(hw_dev->map_base + LCDSADDR3);
+
+	printf(" Video hardware info:\n");
+	printf("  Video clock is running at %u Hz\n",
+		s3c24xx_get_hclk() / ((GET_CLKVAL(con1) + 1) * 2));
+	printf("  Video memory bank starts at 0x%08X\n",
+		GET_LCDBANK(addr1) << 22);
+	printf("  Video memory bank offset: 0x%08X\n",
+		GET_LCDBASEU(addr1));
+	printf("  Video memory end: 0x%08X\n",
+		GET_LCDBASEU(addr2));
+	printf("  Virtual screen offset size: %u half words\n",
+		GET_OFFSIZE(addr3));
+	printf("  Virtual screen page width: %u half words\n",
+		GET_PAGE_WIDTH(addr3));
+}
+#endif
+
+/*
+ * There is only one video hardware instance available.
+ * It makes no sense to dynamically allocate this data
+ */
+static struct s3cfb_host host_data = {
+	.fb_data.fb_mode = s3cfb_initialize_mode,
+	.fb_data.fb_enable = s3cfb_enable_controller,
+	.fb_data.fb_disable = s3cfb_disable_controller,
+};
+
+static int s3cfb_probe(struct device_d *hw_dev)
+{
+	struct s3c_fb_platform_data *pdata = hw_dev->platform_data;
+	struct device_d *fb_dev;
+
+	if (pdata == NULL) {
+		dev_err(hw_dev, "Framebuffer driver missing platform data");
+		return -ENODEV;
+	}
+
+	/* enable unit's clock */
+	s3c244x_mod_clock(CLK_LCDC, 1);
+
+	writel(0, hw_dev->map_base + LCDCON1);
+
+	/** @todo S3C2440: LCD power disable via platform data */
+	writel(0, hw_dev->map_base + LCDCON5);
+
+	/* disable it again until user request */
+	s3c244x_mod_clock(CLK_LCDC, 0);
+
+	/* add runtime hardware info */
+	host_data.hw_dev = hw_dev;
+	host_data.base = (void*)hw_dev->map_base;
+
+	/* add runtime video info */
+	host_data.fb_data.mode = pdata->mode_list;
+	host_data.fb_data.mode_cnt = pdata->mode_cnt;
+
+	fb_dev = register_framebuffer(&host_data.fb_data);
+	if (fb_dev == NULL) {
+		dev_err(hw_dev, "Failed to register framebuffer\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct driver_d s3cfb_driver = {
+	.name	= "s3cfb",
+	.probe	= s3cfb_probe,
+#ifdef CONFIG_VIDEO_INFO_VERBOSE
+	.info	= s3cfb_info,
+#endif
+};
+
+static int s3cfb_init(void)
+{
+	return register_driver(&s3cfb_driver);
+}
+
+device_initcall(s3cfb_init);
+
+/**
+ * The S3C244x LCD controller supports passive (CSTN/STN) and active (TFT)
+ * LC displays
+ *
+ * The driver itself currently supports only active TFT LC displays in the
+ * follwing manner:
+ *
+ *  * True colours
+ *    - 16 bpp
+ *    - 24 bpp
+ */
-- 
1.7.2.3




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