diff options
Diffstat (limited to 'drivers/video/fbdev/ocfb.c')
| -rw-r--r-- | drivers/video/fbdev/ocfb.c | 440 | 
1 files changed, 440 insertions, 0 deletions
diff --git a/drivers/video/fbdev/ocfb.c b/drivers/video/fbdev/ocfb.c new file mode 100644 index 00000000000..7f9dc9bec30 --- /dev/null +++ b/drivers/video/fbdev/ocfb.c @@ -0,0 +1,440 @@ +/* + * OpenCores VGA/LCD 2.0 core frame buffer driver + * + * Copyright (C) 2013 Stefan Kristiansson, stefan.kristiansson@saunalahti.fi + * + * This file is licensed under the terms of the GNU General Public License + * version 2.  This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/fb.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/slab.h> + +/* OCFB register defines */ +#define OCFB_CTRL	0x000 +#define OCFB_STAT	0x004 +#define OCFB_HTIM	0x008 +#define OCFB_VTIM	0x00c +#define OCFB_HVLEN	0x010 +#define OCFB_VBARA	0x014 +#define OCFB_PALETTE	0x800 + +#define OCFB_CTRL_VEN	0x00000001 /* Video Enable */ +#define OCFB_CTRL_HIE	0x00000002 /* HSync Interrupt Enable */ +#define OCFB_CTRL_PC	0x00000800 /* 8-bit Pseudo Color Enable*/ +#define OCFB_CTRL_CD8	0x00000000 /* Color Depth 8 */ +#define OCFB_CTRL_CD16	0x00000200 /* Color Depth 16 */ +#define OCFB_CTRL_CD24	0x00000400 /* Color Depth 24 */ +#define OCFB_CTRL_CD32	0x00000600 /* Color Depth 32 */ +#define OCFB_CTRL_VBL1	0x00000000 /* Burst Length 1 */ +#define OCFB_CTRL_VBL2	0x00000080 /* Burst Length 2 */ +#define OCFB_CTRL_VBL4	0x00000100 /* Burst Length 4 */ +#define OCFB_CTRL_VBL8	0x00000180 /* Burst Length 8 */ + +#define PALETTE_SIZE	256 + +#define OCFB_NAME	"OC VGA/LCD" + +static char *mode_option; + +static const struct fb_videomode default_mode = { +	/* 640x480 @ 60 Hz, 31.5 kHz hsync */ +	NULL, 60, 640, 480, 39721, 40, 24, 32, 11, 96, 2, +	0, FB_VMODE_NONINTERLACED +}; + +struct ocfb_dev { +	struct fb_info info; +	void __iomem *regs; +	/* flag indicating whether the regs are little endian accessed */ +	int little_endian; +	/* Physical and virtual addresses of framebuffer */ +	phys_addr_t fb_phys; +	void __iomem *fb_virt; +	u32 pseudo_palette[PALETTE_SIZE]; +}; + +#ifndef MODULE +static int __init ocfb_setup(char *options) +{ +	char *curr_opt; + +	if (!options || !*options) +		return 0; + +	while ((curr_opt = strsep(&options, ",")) != NULL) { +		if (!*curr_opt) +			continue; +		mode_option = curr_opt; +	} + +	return 0; +} +#endif + +static inline u32 ocfb_readreg(struct ocfb_dev *fbdev, loff_t offset) +{ +	if (fbdev->little_endian) +		return ioread32(fbdev->regs + offset); +	else +		return ioread32be(fbdev->regs + offset); +} + +static void ocfb_writereg(struct ocfb_dev *fbdev, loff_t offset, u32 data) +{ +	if (fbdev->little_endian) +		iowrite32(data, fbdev->regs + offset); +	else +		iowrite32be(data, fbdev->regs + offset); +} + +static int ocfb_setupfb(struct ocfb_dev *fbdev) +{ +	unsigned long bpp_config; +	struct fb_var_screeninfo *var = &fbdev->info.var; +	struct device *dev = fbdev->info.device; +	u32 hlen; +	u32 vlen; + +	/* Disable display */ +	ocfb_writereg(fbdev, OCFB_CTRL, 0); + +	/* Register framebuffer address */ +	fbdev->little_endian = 0; +	ocfb_writereg(fbdev, OCFB_VBARA, fbdev->fb_phys); + +	/* Detect endianess */ +	if (ocfb_readreg(fbdev, OCFB_VBARA) != fbdev->fb_phys) { +		fbdev->little_endian = 1; +		ocfb_writereg(fbdev, OCFB_VBARA, fbdev->fb_phys); +	} + +	/* Horizontal timings */ +	ocfb_writereg(fbdev, OCFB_HTIM, (var->hsync_len - 1) << 24 | +		      (var->right_margin - 1) << 16 | (var->xres - 1)); + +	/* Vertical timings */ +	ocfb_writereg(fbdev, OCFB_VTIM, (var->vsync_len - 1) << 24 | +		      (var->lower_margin - 1) << 16 | (var->yres - 1)); + +	/* Total length of frame */ +	hlen = var->left_margin + var->right_margin + var->hsync_len + +		var->xres; + +	vlen = var->upper_margin + var->lower_margin + var->vsync_len + +		var->yres; + +	ocfb_writereg(fbdev, OCFB_HVLEN, (hlen - 1) << 16 | (vlen - 1)); + +	bpp_config = OCFB_CTRL_CD8; +	switch (var->bits_per_pixel) { +	case 8: +		if (!var->grayscale) +			bpp_config |= OCFB_CTRL_PC;  /* enable palette */ +		break; + +	case 16: +		bpp_config |= OCFB_CTRL_CD16; +		break; + +	case 24: +		bpp_config |= OCFB_CTRL_CD24; +		break; + +	case 32: +		bpp_config |= OCFB_CTRL_CD32; +		break; + +	default: +		dev_err(dev, "no bpp specified\n"); +		break; +	} + +	/* maximum (8) VBL (video memory burst length) */ +	bpp_config |= OCFB_CTRL_VBL8; + +	/* Enable output */ +	ocfb_writereg(fbdev, OCFB_CTRL, (OCFB_CTRL_VEN | bpp_config)); + +	return 0; +} + +static int ocfb_setcolreg(unsigned regno, unsigned red, unsigned green, +			  unsigned blue, unsigned transp, +			  struct fb_info *info) +{ +	struct ocfb_dev *fbdev = (struct ocfb_dev *)info->par; +	u32 color; + +	if (regno >= info->cmap.len) { +		dev_err(info->device, "regno >= cmap.len\n"); +		return 1; +	} + +	if (info->var.grayscale) { +		/* grayscale = 0.30*R + 0.59*G + 0.11*B */ +		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8; +	} + +	red >>= (16 - info->var.red.length); +	green >>= (16 - info->var.green.length); +	blue >>= (16 - info->var.blue.length); +	transp >>= (16 - info->var.transp.length); + +	if (info->var.bits_per_pixel == 8 && !info->var.grayscale) { +		regno <<= 2; +		color = (red << 16) | (green << 8) | blue; +		ocfb_writereg(fbdev, OCFB_PALETTE + regno, color); +	} else { +		((u32 *)(info->pseudo_palette))[regno] = +			(red << info->var.red.offset) | +			(green << info->var.green.offset) | +			(blue << info->var.blue.offset) | +			(transp << info->var.transp.offset); +	} + +	return 0; +} + +static int ocfb_init_fix(struct ocfb_dev *fbdev) +{ +	struct fb_var_screeninfo *var = &fbdev->info.var; +	struct fb_fix_screeninfo *fix = &fbdev->info.fix; + +	strcpy(fix->id, OCFB_NAME); + +	fix->line_length = var->xres * var->bits_per_pixel/8; +	fix->smem_len = fix->line_length * var->yres; +	fix->type = FB_TYPE_PACKED_PIXELS; + +	if (var->bits_per_pixel == 8 && !var->grayscale) +		fix->visual = FB_VISUAL_PSEUDOCOLOR; +	else +		fix->visual = FB_VISUAL_TRUECOLOR; + +	return 0; +} + +static int ocfb_init_var(struct ocfb_dev *fbdev) +{ +	struct fb_var_screeninfo *var = &fbdev->info.var; + +	var->accel_flags = FB_ACCEL_NONE; +	var->activate = FB_ACTIVATE_NOW; +	var->xres_virtual = var->xres; +	var->yres_virtual = var->yres; + +	switch (var->bits_per_pixel) { +	case 8: +		var->transp.offset = 0; +		var->transp.length = 0; +		var->red.offset = 0; +		var->red.length = 8; +		var->green.offset = 0; +		var->green.length = 8; +		var->blue.offset = 0; +		var->blue.length = 8; +		break; + +	case 16: +		var->transp.offset = 0; +		var->transp.length = 0; +		var->red.offset = 11; +		var->red.length = 5; +		var->green.offset = 5; +		var->green.length = 6; +		var->blue.offset = 0; +		var->blue.length  = 5; +		break; + +	case 24: +		var->transp.offset = 0; +		var->transp.length = 0; +		var->red.offset = 16; +		var->red.length = 8; +		var->green.offset = 8; +		var->green.length = 8; +		var->blue.offset = 0; +		var->blue.length = 8; +		break; + +	case 32: +		var->transp.offset = 24; +		var->transp.length = 8; +		var->red.offset = 16; +		var->red.length = 8; +		var->green.offset = 8; +		var->green.length = 8; +		var->blue.offset = 0; +		var->blue.length = 8; +		break; +	} + +	return 0; +} + +static struct fb_ops ocfb_ops = { +	.owner		= THIS_MODULE, +	.fb_setcolreg	= ocfb_setcolreg, +	.fb_fillrect	= cfb_fillrect, +	.fb_copyarea	= cfb_copyarea, +	.fb_imageblit	= cfb_imageblit, +}; + +static int ocfb_probe(struct platform_device *pdev) +{ +	int ret = 0; +	struct ocfb_dev *fbdev; +	struct resource *res; +	int fbsize; + +	fbdev = devm_kzalloc(&pdev->dev, sizeof(*fbdev), GFP_KERNEL); +	if (!fbdev) +		return -ENOMEM; + +	platform_set_drvdata(pdev, fbdev); + +	fbdev->info.fbops = &ocfb_ops; +	fbdev->info.device = &pdev->dev; +	fbdev->info.par = fbdev; + +	/* Video mode setup */ +	if (!fb_find_mode(&fbdev->info.var, &fbdev->info, mode_option, +			  NULL, 0, &default_mode, 16)) { +		dev_err(&pdev->dev, "No valid video modes found\n"); +		return -EINVAL; +	} +	ocfb_init_var(fbdev); +	ocfb_init_fix(fbdev); + +	/* Request I/O resource */ +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0); +	if (!res) { +		dev_err(&pdev->dev, "I/O resource request failed\n"); +		return -ENXIO; +	} +	res->flags &= ~IORESOURCE_CACHEABLE; +	fbdev->regs = devm_ioremap_resource(&pdev->dev, res); +	if (IS_ERR(fbdev->regs)) +		return PTR_ERR(fbdev->regs); + +	/* Allocate framebuffer memory */ +	fbsize = fbdev->info.fix.smem_len; +	fbdev->fb_virt = dma_alloc_coherent(&pdev->dev, PAGE_ALIGN(fbsize), +					    &fbdev->fb_phys, GFP_KERNEL); +	if (!fbdev->fb_virt) { +		dev_err(&pdev->dev, +			"Frame buffer memory allocation failed\n"); +		return -ENOMEM; +	} +	fbdev->info.fix.smem_start = fbdev->fb_phys; +	fbdev->info.screen_base = fbdev->fb_virt; +	fbdev->info.pseudo_palette = fbdev->pseudo_palette; + +	/* Clear framebuffer */ +	memset_io(fbdev->fb_virt, 0, fbsize); + +	/* Setup and enable the framebuffer */ +	ocfb_setupfb(fbdev); + +	if (fbdev->little_endian) +		fbdev->info.flags |= FBINFO_FOREIGN_ENDIAN; + +	/* Allocate color map */ +	ret = fb_alloc_cmap(&fbdev->info.cmap, PALETTE_SIZE, 0); +	if (ret) { +		dev_err(&pdev->dev, "Color map allocation failed\n"); +		goto err_dma_free; +	} + +	/* Register framebuffer */ +	ret = register_framebuffer(&fbdev->info); +	if (ret) { +		dev_err(&pdev->dev, "Framebuffer registration failed\n"); +		goto err_dealloc_cmap; +	} + +	return 0; + +err_dealloc_cmap: +	fb_dealloc_cmap(&fbdev->info.cmap); + +err_dma_free: +	dma_free_coherent(&pdev->dev, PAGE_ALIGN(fbsize), fbdev->fb_virt, +			  fbdev->fb_phys); + +	return ret; +} + +static int ocfb_remove(struct platform_device *pdev) +{ +	struct ocfb_dev *fbdev = platform_get_drvdata(pdev); + +	unregister_framebuffer(&fbdev->info); +	fb_dealloc_cmap(&fbdev->info.cmap); +	dma_free_coherent(&pdev->dev, PAGE_ALIGN(fbdev->info.fix.smem_len), +			  fbdev->fb_virt, fbdev->fb_phys); + +	/* Disable display */ +	ocfb_writereg(fbdev, OCFB_CTRL, 0); + +	platform_set_drvdata(pdev, NULL); + +	return 0; +} + +static struct of_device_id ocfb_match[] = { +	{ .compatible = "opencores,ocfb", }, +	{}, +}; +MODULE_DEVICE_TABLE(of, ocfb_match); + +static struct platform_driver ocfb_driver = { +	.probe  = ocfb_probe, +	.remove	= ocfb_remove, +	.driver = { +		.name = "ocfb_fb", +		.of_match_table = ocfb_match, +	} +}; + +/* + * Init and exit routines + */ +static int __init ocfb_init(void) +{ +#ifndef MODULE +	char *option = NULL; + +	if (fb_get_options("ocfb", &option)) +		return -ENODEV; +	ocfb_setup(option); +#endif +	return platform_driver_register(&ocfb_driver); +} + +static void __exit ocfb_exit(void) +{ +	platform_driver_unregister(&ocfb_driver); +} + +module_init(ocfb_init); +module_exit(ocfb_exit); + +MODULE_AUTHOR("Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>"); +MODULE_DESCRIPTION("OpenCores VGA/LCD 2.0 frame buffer driver"); +MODULE_LICENSE("GPL v2"); +module_param(mode_option, charp, 0); +MODULE_PARM_DESC(mode_option, "Video mode ('<xres>x<yres>[-<bpp>][@refresh]')");  | 
