igafb.c

Linux环境下视频显示卡设备的驱动程序源代码

/*
 *  linux/drivers/video/igafb.c -- Frame buffer device for IGA 1682
 *
 *      Copyright (C) 1998  Vladimir Roganov and Gleb Raiko
 *
 *  This driver is partly based on the Frame buffer device for ATI Mach64
 *  and partially on VESA-related code.
 *
 *      Copyright (C) 1997-1998  Geert Uytterhoeven
 *      Copyright (C) 1998  Bernd Harries
 *      Copyright (C) 1998  Eddie C. Dost  ([e-mail])
 *
 *  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.
 */

/******************************************************************************

  TODO:
       Despite of IGA Card has advanced graphic acceleration, 
       initial version is almost dummy and does not support it.
       Support for video modes and acceleration must be added
       together with accelerated X-Windows driver implementation.

       Most important thing at this moment is that we have working
       JavaEngine1  console & X  with new console interface.

******************************************************************************/

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/nvram.h>

#include <asm/io.h>

#ifdef CONFIG_SPARC
#include <asm/prom.h>
#include <asm/pcic.h>
#endif

#include <video/iga.h>

struct pci_mmap_map {
    unsigned long voff;
    unsigned long poff;
    unsigned long size;
    unsigned long prot_flag;
    unsigned long prot_mask;
};

struct iga_par {
	struct pci_mmap_map *mmap_map;
	unsigned long frame_buffer_phys;
	unsigned long io_base;
};

struct fb_info fb_info;

struct fb_fix_screeninfo igafb_fix __initdata = {
        .id		= "IGA 1682",
	.type		= FB_TYPE_PACKED_PIXELS,
	.mmio_len 	= 1000
};

struct fb_var_screeninfo default_var = {
	/* 640x480, 60 Hz, Non-Interlaced (25.175 MHz dotclock) */
	.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 },
	.height		= -1,
	.width		= -1,
	.accel_flags	= FB_ACCEL_NONE,
	.pixclock	= 39722,
	.left_margin	= 48,
	.right_margin	= 16,
	.upper_margin	= 33,
	.lower_margin	= 10,
	.hsync_len	= 96,
	.vsync_len	= 2,
	.vmode		= FB_VMODE_NONINTERLACED
};

#ifdef CONFIG_SPARC
struct fb_var_screeninfo default_var_1024x768 __initdata = {
	/* 1024x768, 75 Hz, Non-Interlaced (78.75 MHz dotclock) */
	.xres		= 1024,
	.yres		= 768,
	.xres_virtual	= 1024,
	.yres_virtual	= 768,
	.bits_per_pixel	= 8,
	.red		= {0, 8, 0 },
	.green		= {0, 8, 0 },
	.blue		= {0, 8, 0 },
	.height		= -1,
	.width		= -1,
	.accel_flags	= FB_ACCEL_NONE,
	.pixclock	= 12699,
	.left_margin	= 176,
	.right_margin	= 16,
	.upper_margin	= 28,
	.lower_margin	= 1,
	.hsync_len	= 96,
	.vsync_len	= 3,
	.vmode		= FB_SYNC_HOR_HIGH_ACT|FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED
};

struct fb_var_screeninfo default_var_1152x900 __initdata = {
	/* 1152x900, 76 Hz, Non-Interlaced (110.0 MHz dotclock) */
	.xres		= 1152,
	.yres		= 900,
	.xres_virtual	= 1152,
	.yres_virtual	= 900,
	.bits_per_pixel	= 8,
	.red		= { 0, 8, 0 },
	.green		= { 0, 8, 0 },
	.blue		= { 0, 8, 0 },
	.height		= -1,
	.width		= -1,
	.accel_flags	= FB_ACCEL_NONE,
	.pixclock	= 9091,
	.left_margin	= 234,
	.right_margin	= 24,
	.upper_margin	= 34,
	.lower_margin	= 3,
	.hsync_len	= 100,
	.vsync_len	= 3,
	.vmode		= FB_SYNC_HOR_HIGH_ACT|FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED
};

struct fb_var_screeninfo default_var_1280x1024 __initdata = {
	/* 1280x1024, 75 Hz, Non-Interlaced (135.00 MHz dotclock) */
	.xres		= 1280,
	.yres		= 1024,
	.xres_virtual	= 1280,
	.yres_virtual	= 1024,
	.bits_per_pixel	= 8,
	.red		= {0, 8, 0 }, 
	.green		= {0, 8, 0 },
	.blue		= {0, 8, 0 },
	.height		= -1,
	.width		= -1,
	.accel_flags	= 0,
	.pixclock	= 7408,
	.left_margin	= 248,
	.right_margin	= 16,
	.upper_margin	= 38,
	.lower_margin	= 1,
	.hsync_len	= 144,
	.vsync_len	= 3,
	.vmode		= FB_SYNC_HOR_HIGH_ACT|FB_SYNC_VERT_HIGH_ACT, FB_VMODE_NONINTERLACED
};

/*
 *   Memory-mapped I/O functions for Sparc PCI
 *
 * On sparc we happen to access I/O with memory mapped functions too.
 */ 
#define pci_inb(par, reg)        readb(par->io_base+(reg))
#define pci_outb(par, val, reg)  writeb(val, par->io_base+(reg))

static inline unsigned int iga_inb(struct iga_par *par, unsigned int reg,
				   unsigned int idx)
{
        pci_outb(par, idx, reg);
        return pci_inb(par, reg + 1);
}

static inline void iga_outb(struct iga_par *par, unsigned char val,
			    unsigned int reg, unsigned int idx )
{
        pci_outb(par, idx, reg);
        pci_outb(par, val, reg+1);
}

#endif /* CONFIG_SPARC */

/*
 *  Very important functionality for the JavaEngine1 computer:
 *  make screen border black (usign special IGA registers) 
 */
static void iga_blank_border(struct iga_par *par)
{
        int i;
#if 0
	/*
	 * PROM does this for us, so keep this code as a reminder
	 * about required read from 0x3DA and writing of 0x20 in the end.
	 */
	(void) pci_inb(par, 0x3DA);		/* required for every access */
	pci_outb(par, IGA_IDX_VGA_OVERSCAN, IGA_ATTR_CTL);
	(void) pci_inb(par, IGA_ATTR_CTL+1);
	pci_outb(par, 0x38, IGA_ATTR_CTL);
	pci_outb(par, 0x20, IGA_ATTR_CTL);	/* re-enable visual */
#endif
	/*
	 * This does not work as it was designed because the overscan
	 * color is looked up in the palette. Therefore, under X11
	 * overscan changes color.
	 */
	for (i=0; i < 3; i++)
		iga_outb(par, 0, IGA_EXT_CNTRL, IGA_IDX_OVERSCAN_COLOR + i);
}

#ifdef CONFIG_SPARC
static int igafb_mmap(struct fb_info *info,
		      struct vm_area_struct *vma)
{
	struct iga_par *par = (struct iga_par *)info->par;
	unsigned int size, page, map_size = 0;
	unsigned long map_offset = 0;
	int i;

	if (!par->mmap_map)
		return -ENXIO;

	size = vma->vm_end - vma->vm_start;

	/* Each page, see which map applies */
	for (page = 0; page < size; ) {
		map_size = 0;
		for (i = 0; par->mmap_map[i].size; i++) {
			unsigned long start = par->mmap_map[i].voff;
			unsigned long end = start + par->mmap_map[i].size;
			unsigned long offset = (vma->vm_pgoff << PAGE_SHIFT) + page;

			if (start > offset)
				continue;
			if (offset >= end)
				continue;

			map_size = par->mmap_map[i].size - (offset - start);
			map_offset = par->mmap_map[i].poff + (offset - start);
			break;
		}
		if (!map_size) {
			page += PAGE_SIZE;
			continue;
		}
		if (page + map_size > size)
			map_size = size - page;

		pgprot_val(vma->vm_page_prot) &= ~(par->mmap_map[i].prot_mask);
		pgprot_val(vma->vm_page_prot) |= par->mmap_map[i].prot_flag;

		if (remap_pfn_range(vma, vma->vm_start + page,
			map_offset >> PAGE_SHIFT, map_size, vma->vm_page_prot))
			return -EAGAIN;

		page += map_size;
	}

	if (!map_size)
		return -EINVAL;

	vma->vm_flags |= VM_IO;
	return 0;
}
#endif /* CONFIG_SPARC */

static int igafb_setcolreg(unsigned regno, unsigned red, unsigned green,
                           unsigned blue, unsigned transp,
                           struct fb_info *info)
{
        /*
         *  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.
         */
	struct iga_par *par = (struct iga_par *)info->par;

        if (regno >= info->cmap.len)
                return 1;

	pci_outb(par, regno, DAC_W_INDEX);