|  | /* | 
|  | * 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 */ | 
|  | dma_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->left_margin - 1) << 16 | (var->xres - 1)); | 
|  |  | 
|  | /* Vertical timings */ | 
|  | ocfb_writereg(fbdev, OCFB_VTIM, (var->vsync_len - 1) << 24 | | 
|  | (var->upper_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; | 
|  | } | 
|  | 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]')"); |