--- /dev/null
+/*
+ * linux/drivers/video/vfb.c -- Virtual frame buffer device
+ *
+ * Copyright (C) 2002 James Simmons
+ *
+ * Copyright (C) 1997 Geert Uytterhoeven
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <linux/fb.h>
+#include <linux/init.h>
+
+ /*
+ * RAM we reserve for the frame buffer. This defines the maximum screen
+ * size
+ *
+ * The default can be overridden if the driver is compiled as a module
+ */
+
+#define VIDEOMEMSIZE (1*1024*1024) /* 1 MB */
+
+static void *videomemory;
+static u_long videomemorysize = VIDEOMEMSIZE;
+module_param(videomemorysize, ulong, 0);
+
+/**********************************************************************
+ *
+ * Memory management
+ *
+ **********************************************************************/
+static void *rvmalloc(unsigned long size)
+{
+ void *mem;
+ unsigned long adr;
+
+ size = PAGE_ALIGN(size);
+ mem = vmalloc_32(size);
+ if (!mem)
+ return NULL;
+
+ memset(mem, 0, size); /* Clear the ram out, no junk to the user */
+ adr = (unsigned long) mem;
+ while (size > 0) {
+ SetPageReserved(vmalloc_to_page((void *)adr));
+ adr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+
+ return mem;
+}
+
+static void rvfree(void *mem, unsigned long size)
+{
+ unsigned long adr;
+
+ if (!mem)
+ return;
+
+ adr = (unsigned long) mem;
+ while ((long) size > 0) {
+ ClearPageReserved(vmalloc_to_page((void *)adr));
+ adr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ vfree(mem);
+}
+
+static struct fb_var_screeninfo vfb_default = {
+ .xres = 640,
+ .yres = 480,
+ .xres_virtual = 640,
+ .yres_virtual = 480,
+ .bits_per_pixel = 8,
+ .red = { 0, 8, 0 },
+ .green = { 0, 8, 0 },
+ .blue = { 0, 8, 0 },
+ .activate = FB_ACTIVATE_TEST,
+ .height = -1,
+ .width = -1,
+ .pixclock = 20000,
+ .left_margin = 64,
+ .right_margin = 64,
+ .upper_margin = 32,
+ .lower_margin = 32,
+ .hsync_len = 64,
+ .vsync_len = 2,
+ .vmode = FB_VMODE_NONINTERLACED,
+};
+
+static struct fb_fix_screeninfo vfb_fix = {
+ .id = "Virtual FB",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_PSEUDOCOLOR,
+ .xpanstep = 1,
+ .ypanstep = 1,
+ .ywrapstep = 1,
+ .accel = FB_ACCEL_NONE,
+};
+
+static bool vfb_enable __initdata = 0; /* disabled by default */
+module_param(vfb_enable, bool, 0);
+
+static int vfb_check_var(struct fb_var_screeninfo *var,
+ struct fb_info *info);
+static int vfb_set_par(struct fb_info *info);
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+ u_int transp, struct fb_info *info);
+static int vfb_pan_display(struct fb_var_screeninfo *var,
+ struct fb_info *info);
+static int vfb_mmap(struct fb_info *info,
+ struct vm_area_struct *vma);
+
+static struct fb_ops vfb_ops = {
+ .fb_read = fb_sys_read,
+ .fb_write = fb_sys_write,
+ .fb_check_var = vfb_check_var,
+ .fb_set_par = vfb_set_par,
+ .fb_setcolreg = vfb_setcolreg,
+ .fb_pan_display = vfb_pan_display,
+ .fb_fillrect = sys_fillrect,
+ .fb_copyarea = sys_copyarea,
+ .fb_imageblit = sys_imageblit,
+ .fb_mmap = vfb_mmap,
+};
+
+ /*
+ * Internal routines
+ */
+
+static u_long get_line_length(int xres_virtual, int bpp)
+{
+ u_long length;
+
+ length = xres_virtual * bpp;
+ length = (length + 31) & ~31;
+ length >>= 3;
+ return (length);
+}
+
+ /*
+ * Setting the video mode has been split into two parts.
+ * First part, xxxfb_check_var, must not write anything
+ * to hardware, it should only verify and adjust var.
+ * This means it doesn't alter par but it does use hardware
+ * data from it to check this var.
+ */
+
+static int vfb_check_var(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ u_long line_length;
+
+ /*
+ * FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
+ * as FB_VMODE_SMOOTH_XPAN is only used internally
+ */
+
+ if (var->vmode & FB_VMODE_CONUPDATE) {
+ var->vmode |= FB_VMODE_YWRAP;
+ var->xoffset = info->var.xoffset;
+ var->yoffset = info->var.yoffset;
+ }
+
+ /*
+ * Some very basic checks
+ */
+ if (!var->xres)
+ var->xres = 1;
+ if (!var->yres)
+ var->yres = 1;
+ if (var->xres > var->xres_virtual)
+ var->xres_virtual = var->xres;
+ if (var->yres > var->yres_virtual)
+ var->yres_virtual = var->yres;
+ if (var->bits_per_pixel <= 1)
+ var->bits_per_pixel = 1;
+ else if (var->bits_per_pixel <= 8)
+ var->bits_per_pixel = 8;
+ else if (var->bits_per_pixel <= 16)
+ var->bits_per_pixel = 16;
+ else if (var->bits_per_pixel <= 24)
+ var->bits_per_pixel = 24;
+ else if (var->bits_per_pixel <= 32)
+ var->bits_per_pixel = 32;
+ else
+ return -EINVAL;
+
+ if (var->xres_virtual < var->xoffset + var->xres)
+ var->xres_virtual = var->xoffset + var->xres;
+ if (var->yres_virtual < var->yoffset + var->yres)
+ var->yres_virtual = var->yoffset + var->yres;
+
+ /*
+ * Memory limit
+ */
+ line_length =
+ get_line_length(var->xres_virtual, var->bits_per_pixel);
+ if (line_length * var->yres_virtual > videomemorysize)
+ return -ENOMEM;
+
+ /*
+ * Now that we checked it we alter var. The reason being is that the video
+ * mode passed in might not work but slight changes to it might make it
+ * work. This way we let the user know what is acceptable.
+ */
+ switch (var->bits_per_pixel) {
+ case 1:
+ case 8:
+ var->red.offset = 0;
+ var->red.length = 8;
+ var->green.offset = 0;
+ var->green.length = 8;
+ var->blue.offset = 0;
+ var->blue.length = 8;
+ var->transp.offset = 0;
+ var->transp.length = 0;
+ break;
+ case 16: /* RGBA 5551 */
+ if (var->transp.length) {
+ var->red.offset = 0;
+ var->red.length = 5;
+ var->green.offset = 5;
+ var->green.length = 5;
+ var->blue.offset = 10;
+ var->blue.length = 5;
+ var->transp.offset = 15;
+ var->transp.length = 1;
+ } else { /* RGB 565 */
+ var->red.offset = 0;
+ var->red.length = 5;
+ var->green.offset = 5;
+ var->green.length = 6;
+ var->blue.offset = 11;
+ var->blue.length = 5;
+ var->transp.offset = 0;
+ var->transp.length = 0;
+ }
+ break;
+ case 24: /* RGB 888 */
+ var->red.offset = 0;
+ var->red.length = 8;
+ var->green.offset = 8;
+ var->green.length = 8;
+ var->blue.offset = 16;
+ var->blue.length = 8;
+ var->transp.offset = 0;
+ var->transp.length = 0;
+ break;
+ case 32: /* RGBA 8888 */
+ var->red.offset = 0;
+ var->red.length = 8;
+ var->green.offset = 8;
+ var->green.length = 8;
+ var->blue.offset = 16;
+ var->blue.length = 8;
+ var->transp.offset = 24;
+ var->transp.length = 8;
+ break;
+ }
+ var->red.msb_right = 0;
+ var->green.msb_right = 0;
+ var->blue.msb_right = 0;
+ var->transp.msb_right = 0;
+
+ return 0;
+}
+
+/* This routine actually sets the video mode. It's in here where we
+ * the hardware state info->par and fix which can be affected by the
+ * change in par. For this driver it doesn't do much.
+ */
+static int vfb_set_par(struct fb_info *info)
+{
+ info->fix.line_length = get_line_length(info->var.xres_virtual,
+ info->var.bits_per_pixel);
+ return 0;
+}
+
+ /*
+ * Set a single color register. The values supplied are already
+ * rounded down to the hardware's capabilities (according to the
+ * entries in the var structure). Return != 0 for invalid regno.
+ */
+
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+ u_int transp, struct fb_info *info)
+{
+ if (regno >= 256) /* no. of hw registers */
+ return 1;
+ /*
+ * Program hardware... do anything you want with transp
+ */
+
+ /* grayscale works only partially under directcolor */
+ if (info->var.grayscale) {
+ /* grayscale = 0.30*R + 0.59*G + 0.11*B */
+ red = green = blue =
+ (red * 77 + green * 151 + blue * 28) >> 8;
+ }
+
+ /* Directcolor:
+ * var->{color}.offset contains start of bitfield
+ * var->{color}.length contains length of bitfield
+ * {hardwarespecific} contains width of RAMDAC
+ * cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
+ * RAMDAC[X] is programmed to (red, green, blue)
+ *
+ * Pseudocolor:
+ * var->{color}.offset is 0 unless the palette index takes less than
+ * bits_per_pixel bits and is stored in the upper
+ * bits of the pixel value
+ * var->{color}.length is set so that 1 << length is the number of available
+ * palette entries
+ * cmap is not used
+ * RAMDAC[X] is programmed to (red, green, blue)
+ *
+ * Truecolor:
+ * does not use DAC. Usually 3 are present.
+ * var->{color}.offset contains start of bitfield
+ * var->{color}.length contains length of bitfield
+ * cmap is programmed to (red << red.offset) | (green << green.offset) |
+ * (blue << blue.offset) | (transp << transp.offset)
+ * RAMDAC does not exist
+ */
+#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
+ switch (info->fix.visual) {
+ case FB_VISUAL_TRUECOLOR:
+ case FB_VISUAL_PSEUDOCOLOR:
+ red = CNVT_TOHW(red, info->var.red.length);
+ green = CNVT_TOHW(green, info->var.green.length);
+ blue = CNVT_TOHW(blue, info->var.blue.length);
+ transp = CNVT_TOHW(transp, info->var.transp.length);
+ break;
+ case FB_VISUAL_DIRECTCOLOR:
+ red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */
+ green = CNVT_TOHW(green, 8);
+ blue = CNVT_TOHW(blue, 8);
+ /* hey, there is bug in transp handling... */
+ transp = CNVT_TOHW(transp, 8);
+ break;
+ }
+#undef CNVT_TOHW
+ /* Truecolor has hardware independent palette */
+ if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+ u32 v;
+
+ if (regno >= 16)
+ return 1;
+
+ v = (red << info->var.red.offset) |
+ (green << info->var.green.offset) |
+ (blue << info->var.blue.offset) |
+ (transp << info->var.transp.offset);
+ switch (info->var.bits_per_pixel) {
+ case 8:
+ break;
+ case 16:
+ ((u32 *) (info->pseudo_palette))[regno] = v;
+ break;
+ case 24:
+ case 32:
+ ((u32 *) (info->pseudo_palette))[regno] = v;
+ break;
+ }
+ return 0;
+ }
+ return 0;
+}
+
+ /*
+ * Pan or Wrap the Display
+ *
+ * This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
+ */
+
+static int vfb_pan_display(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ if (var->vmode & FB_VMODE_YWRAP) {
+ if (var->yoffset >= info->var.yres_virtual ||
+ var->xoffset)
+ return -EINVAL;
+ } else {
+ if (var->xoffset + info->var.xres > info->var.xres_virtual ||
+ var->yoffset + info->var.yres > info->var.yres_virtual)
+ return -EINVAL;
+ }
+ info->var.xoffset = var->xoffset;
+ info->var.yoffset = var->yoffset;
+ if (var->vmode & FB_VMODE_YWRAP)
+ info->var.vmode |= FB_VMODE_YWRAP;
+ else
+ info->var.vmode &= ~FB_VMODE_YWRAP;
+ return 0;
+}
+
+ /*
+ * Most drivers don't need their own mmap function
+ */
+
+static int vfb_mmap(struct fb_info *info,
+ struct vm_area_struct *vma)
+{
+ unsigned long start = vma->vm_start;
+ unsigned long size = vma->vm_end - vma->vm_start;
+ unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+ unsigned long page, pos;
+
+ if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
+ return -EINVAL;
+ if (size > info->fix.smem_len)
+ return -EINVAL;
+ if (offset > info->fix.smem_len - size)
+ return -EINVAL;
+
+ pos = (unsigned long)info->fix.smem_start + offset;
+
+ while (size > 0) {
+ page = vmalloc_to_pfn((void *)pos);
+ if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) {
+ return -EAGAIN;
+ }
+ start += PAGE_SIZE;
+ pos += PAGE_SIZE;
+ if (size > PAGE_SIZE)
+ size -= PAGE_SIZE;
+ else
+ size = 0;
+ }
+
+ return 0;
+
+}
+
+#ifndef MODULE
+/*
+ * The virtual framebuffer driver is only enabled if explicitly
+ * requested by passing 'video=vfb:' (or any actual options).
+ */
+static int __init vfb_setup(char *options)
+{
+ char *this_opt;
+
+ vfb_enable = 0;
+
+ if (!options)
+ return 1;
+
+ vfb_enable = 1;
+
+ if (!*options)
+ return 1;
+
+ while ((this_opt = strsep(&options, ",")) != NULL) {
+ if (!*this_opt)
+ continue;
+ /* Test disable for backwards compatibility */
+ if (!strcmp(this_opt, "disable"))
+ vfb_enable = 0;
+ }
+ return 1;
+}
+#endif /* MODULE */
+
+ /*
+ * Initialisation
+ */
+
+static int vfb_probe(struct platform_device *dev)
+{
+ struct fb_info *info;
+ int retval = -ENOMEM;
+
+ /*
+ * For real video cards we use ioremap.
+ */
+ if (!(videomemory = rvmalloc(videomemorysize)))
+ return retval;
+
+ /*
+ * VFB must clear memory to prevent kernel info
+ * leakage into userspace
+ * VGA-based drivers MUST NOT clear memory if
+ * they want to be able to take over vgacon
+ */
+ memset(videomemory, 0, videomemorysize);
+
+ info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
+ if (!info)
+ goto err;
+
+ info->screen_base = (char __iomem *)videomemory;
+ info->fbops = &vfb_ops;
+
+ retval = fb_find_mode(&info->var, info, NULL,
+ NULL, 0, NULL, 8);
+
+ if (!retval || (retval == 4))
+ info->var = vfb_default;
+ vfb_fix.smem_start = (unsigned long) videomemory;
+ vfb_fix.smem_len = videomemorysize;
+ info->fix = vfb_fix;
+ info->pseudo_palette = info->par;
+ info->par = NULL;
+ info->flags = FBINFO_FLAG_DEFAULT;
+
+ retval = fb_alloc_cmap(&info->cmap, 256, 0);
+ if (retval < 0)
+ goto err1;
+
+ retval = register_framebuffer(info);
+ if (retval < 0)
+ goto err2;
+ platform_set_drvdata(dev, info);
+
+ fb_info(info, "Virtual frame buffer device, using %ldK of video memory\n",
+ videomemorysize >> 10);
+ return 0;
+err2:
+ fb_dealloc_cmap(&info->cmap);
+err1:
+ framebuffer_release(info);
+err:
+ rvfree(videomemory, videomemorysize);
+ return retval;
+}
+
+static int vfb_remove(struct platform_device *dev)
+{
+ struct fb_info *info = platform_get_drvdata(dev);
+
+ if (info) {
+ unregister_framebuffer(info);
+ rvfree(videomemory, videomemorysize);
+ fb_dealloc_cmap(&info->cmap);
+ framebuffer_release(info);
+ }
+ return 0;
+}
+
+static struct platform_driver vfb_driver = {
+ .probe = vfb_probe,
+ .remove = vfb_remove,
+ .driver = {
+ .name = "vfb",
+ },
+};
+
+static struct platform_device *vfb_device;
+
+static int __init vfb_init(void)
+{
+ int ret = 0;
+
+#ifndef MODULE
+ char *option = NULL;
+
+ if (fb_get_options("vfb", &option))
+ return -ENODEV;
+ vfb_setup(option);
+#endif
+
+ if (!vfb_enable)
+ return -ENXIO;
+
+ ret = platform_driver_register(&vfb_driver);
+
+ if (!ret) {
+ vfb_device = platform_device_alloc("vfb", 0);
+
+ if (vfb_device)
+ ret = platform_device_add(vfb_device);
+ else
+ ret = -ENOMEM;
+
+ if (ret) {
+ platform_device_put(vfb_device);
+ platform_driver_unregister(&vfb_driver);
+ }
+ }
+
+ return ret;
+}
+
+module_init(vfb_init);
+
+#ifdef MODULE
+static void __exit vfb_exit(void)
+{
+ platform_device_unregister(vfb_device);
+ platform_driver_unregister(&vfb_driver);
+}
+
+module_exit(vfb_exit);
+
+MODULE_LICENSE("GPL");
+#endif /* MODULE */
Code Review / kvmfornfv.git / blobdiff