/*
 *  linux/drivers/video/offb.c -- Open Firmware based frame buffer device
 *
 *      Copyright (C) 1997 Geert Uytterhoeven
 *
 *  This driver is partly based on the PowerMac console driver:
 *
 *      Copyright (C) 1996 Paul Mackerras
 *
 *  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/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/prom.h>

#ifdef CONFIG_PPC64
#include <asm/pci-bridge.h>
#endif

#ifdef CONFIG_PPC32
#include <asm/bootx.h>
#endif

#include "macmodes.h"

/* Supported palette hacks */
enum {
        cmap_unknown,
        cmap_m64,               /* ATI Mach64 */
        cmap_r128,              /* ATI Rage128 */
        cmap_M3A,               /* ATI Rage Mobility M3 Head A */
        cmap_M3B,               /* ATI Rage Mobility M3 Head B */
        cmap_radeon,            /* ATI Radeon */
        cmap_gxt2000,           /* IBM GXT2000 */
};

struct offb_par {
        volatile void __iomem *cmap_adr;
        volatile void __iomem *cmap_data;
        int cmap_type;
        int blanked;
};

struct offb_par default_par;

    /*
     *  Interface used by the world
     */

static int offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
                          u_int transp, struct fb_info *info);
static int offb_blank(int blank, struct fb_info *info);

#ifdef CONFIG_PPC32
extern boot_infos_t *boot_infos;
#endif

static struct fb_ops offb_ops = {
        .owner          = THIS_MODULE,
        .fb_setcolreg   = offb_setcolreg,
        .fb_blank       = offb_blank,
        .fb_fillrect    = cfb_fillrect,
        .fb_copyarea    = cfb_copyarea,
        .fb_imageblit   = cfb_imageblit,
};

    /*
     *  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 offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
                          u_int transp, struct fb_info *info)
{
        struct offb_par *par = (struct offb_par *) info->par;
        int i, depth;
        u32 *pal = info->pseudo_palette;

        depth = info->var.bits_per_pixel;
        if (depth == 16)
                depth = (info->var.green.length == 5) ? 15 : 16;

        if (regno > 255 ||
            (depth == 16 && regno > 63) ||
            (depth == 15 && regno > 31))
                return 1;

        if (regno < 16) {
                switch (depth) {
                case 15:
                        pal[regno] = (regno << 10) | (regno << 5) | regno;
                        break;
                case 16:
                        pal[regno] = (regno << 11) | (regno << 5) | regno;
                        break;
                case 24:
                        pal[regno] = (regno << 16) | (regno << 8) | regno;
                        break;
                case 32:
                        i = (regno << 8) | regno;
                        pal[regno] = (i << 16) | i;
                        break;
                }
        }

        red >>= 8;
        green >>= 8;
        blue >>= 8;

        if (!par->cmap_adr)
                return 0;

        switch (par->cmap_type) {
        case cmap_m64:
                writeb(regno, par->cmap_adr);
                writeb(red, par->cmap_data);
                writeb(green, par->cmap_data);
                writeb(blue, par->cmap_data);
                break;
        case cmap_M3A:
                /* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
                out_le32(par->cmap_adr + 0x58,
                         in_le32(par->cmap_adr + 0x58) & ~0x20);
        case cmap_r128:
                /* Set palette index & data */
                out_8(par->cmap_adr + 0xb0, regno);
                out_le32(par->cmap_adr + 0xb4,
                         (red << 16 | green << 8 | blue));
                break;
        case cmap_M3B:
                /* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
                out_le32(par->cmap_adr + 0x58,
                         in_le32(par->cmap_adr + 0x58) | 0x20);
                /* Set palette index & data */
                out_8(par->cmap_adr + 0xb0, regno);
                out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
                break;
        case cmap_radeon:
                /* Set palette index & data (could be smarter) */
                out_8(par->cmap_adr + 0xb0, regno);
                out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
                break;
        case cmap_gxt2000:
                out_le32(((unsigned __iomem *) par->cmap_adr) + regno,
                         (red << 16 | green << 8 | blue));
                break;
        }

        return 0;
}

    /*
     *  Blank the display.
     */

static int offb_blank(int blank, struct fb_info *info)
{
        struct offb_par *par = (struct offb_par *) info->par;
        int i, j;

        if (!par->cmap_adr)
                return 0;

        if (!par->blanked)
                if (!blank)
                        return 0;

        par->blanked = blank;

        if (blank)
                for (i = 0; i < 256; i++) {
                        switch (par->cmap_type) {
                        case cmap_m64:
                                writeb(i, par->cmap_adr);
                                for (j = 0; j < 3; j++)
                                        writeb(0, par->cmap_data);
                                break;
                        case cmap_M3A:
                                /* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
                                out_le32(par->cmap_adr + 0x58,
                                         in_le32(par->cmap_adr + 0x58) & ~0x20);
                        case cmap_r128:
                                /* Set palette index & data */
                                out_8(par->cmap_adr + 0xb0, i);
                                out_le32(par->cmap_adr + 0xb4, 0);
                                break;
                        case cmap_M3B:
                                /* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
                                out_le32(par->cmap_adr + 0x58,
                                         in_le32(par->cmap_adr + 0x58) | 0x20);
                                /* Set palette index & data */
                                out_8(par->cmap_adr + 0xb0, i);
                                out_le32(par->cmap_adr + 0xb4, 0);
                                break;
                        case cmap_radeon:
                                out_8(par->cmap_adr + 0xb0, i);
                                out_le32(par->cmap_adr + 0xb4, 0);
                                break;
                        case cmap_gxt2000:
                                out_le32(((unsigned __iomem *) par->cmap_adr) + i,
                                         0);
                                break;
                        }
        } else
                fb_set_cmap(&info->cmap, info);
        return 0;
}


static void __iomem *offb_map_reg(struct device_node *np, int index,
                                  unsigned long offset, unsigned long size)
{
        const u32 *addrp;
        u64 asize, taddr;
        unsigned int flags;

        addrp = of_get_pci_address(np, index, &asize, &flags);
        if (addrp == NULL)
                addrp = of_get_address(np, index, &asize, &flags);
        if (addrp == NULL)
                return NULL;
        if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
                return NULL;
        if ((offset + size) > asize)
                return NULL;
        taddr = of_translate_address(np, addrp);
        if (taddr == OF_BAD_ADDR)
                return NULL;
        return ioremap(taddr + offset, size);
}

static void __init offb_init_fb(const char *name, const char *full_name,
                                int width, int height, int depth,
                                int pitch, unsigned long address,
                                struct device_node *dp)
{
        unsigned long res_size = pitch * height * (depth + 7) / 8;
        struct offb_par *par = &default_par;
        unsigned long res_start = address;
        struct fb_fix_screeninfo *fix;
        struct fb_var_screeninfo *var;
        struct fb_info *info;
        int size;

        if (!request_mem_region(res_start, res_size, "offb"))
                return;

        printk(KERN_INFO
               "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
               width, height, name, address, depth, pitch);
        if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
                printk(KERN_ERR "%s: can't use depth = %d\n", full_name,
                       depth);
                release_mem_region(res_start, res_size);
                return;
        }

        size = sizeof(struct fb_info) + sizeof(u32) * 16;

        info = kmalloc(size, GFP_ATOMIC);
        
        if (info == 0) {
                release_mem_region(res_start, res_size);
                return;
        }
        memset(info, 0, size);

        fix = &info->fix;
        var = &info->var;

        strcpy(fix->id, "OFfb ");
        strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
        fix->id[sizeof(fix->id) - 1] = '\0';

        var->xres = var->xres_virtual = width;
        var->yres = var->yres_virtual = height;
        fix->line_length = pitch;

        fix->smem_start = address;
        fix->smem_len = pitch * height;
        fix->type = FB_TYPE_PACKED_PIXELS;
        fix->type_aux = 0;

        par->cmap_type = cmap_unknown;
        if (depth == 8) {
                if (dp && !strncmp(name, "ATY,Rage128", 11)) {
                        par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
                        if (par->cmap_adr)
                                par->cmap_type = cmap_r128;
                } else if (dp && (!strncmp(name, "ATY,RageM3pA", 12)
                                  || !strncmp(name, "ATY,RageM3p12A", 14))) {
                        par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
                        if (par->cmap_adr)
                                par->cmap_type = cmap_M3A;
                } else if (dp && !strncmp(name, "ATY,RageM3pB", 12)) {
                        par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
                        if (par->cmap_adr)
                                par->cmap_type = cmap_M3B;
                } else if (dp && !strncmp(name, "ATY,Rage6", 9)) {
                        par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
                        if (par->cmap_adr)
                                par->cmap_type = cmap_radeon;
                } else if (!strncmp(name, "ATY,", 4)) {
                        unsigned long base = address & 0xff000000UL;
                        par->cmap_adr =
                            ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
                        par->cmap_data = par->cmap_adr + 1;
                        par->cmap_type = cmap_m64;
                } else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
                                  of_device_is_compatible(dp, "pci1014,21c"))) {
                        par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
                        if (par->cmap_adr)
                                par->cmap_type = cmap_gxt2000;
                }
                fix->visual = (par->cmap_type != cmap_unknown) ?
                        FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
        } else
                fix->visual = FB_VISUAL_TRUECOLOR;

        var->xoffset = var->yoffset = 0;
        switch (depth) {
        case 8:
                var->bits_per_pixel = 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 15:                /* RGB 555 */
                var->bits_per_pixel = 16;
                var->red.offset = 10;
                var->red.length = 5;
                var->green.offset = 5;
                var->green.length = 5;
                var->blue.offset = 0;
                var->blue.length = 5;
                var->transp.offset = 0;
                var->transp.length = 0;
                break;
        case 16:                /* RGB 565 */
                var->bits_per_pixel = 16;
                var->red.offset = 11;
                var->red.length = 5;
                var->green.offset = 5;
                var->green.length = 6;
                var->blue.offset = 0;
                var->blue.length = 5;
                var->transp.offset = 0;
                var->transp.length = 0;
                break;
        case 32:                /* RGB 888 */
                var->bits_per_pixel = 32;
                var->red.offset = 16;
                var->red.length = 8;
                var->green.offset = 8;
                var->green.length = 8;
                var->blue.offset = 0;
                var->blue.length = 8;
                var->transp.offset = 24;
                var->transp.length = 8;
                break;
        }
        var->red.msb_right = var->green.msb_right = var->blue.msb_right =
            var->transp.msb_right = 0;
        var->grayscale = 0;
        var->nonstd = 0;
        var->activate = 0;
        var->height = var->width = -1;
        var->pixclock = 10000;
        var->left_margin = var->right_margin = 16;
        var->upper_margin = var->lower_margin = 16;
        var->hsync_len = var->vsync_len = 8;
        var->sync = 0;
        var->vmode = FB_VMODE_NONINTERLACED;

        info->fbops = &offb_ops;
        info->screen_base = ioremap(address, fix->smem_len);
        info->par = par;
        info->pseudo_palette = (void *) (info + 1);
        info->flags = FBINFO_DEFAULT;

        fb_alloc_cmap(&info->cmap, 256, 0);

        if (register_framebuffer(info) < 0) {
                iounmap(par->cmap_adr);
                par->cmap_adr = NULL;
                iounmap(info->screen_base);
                kfree(info);
                release_mem_region(res_start, res_size);
                return;
        }

        printk(KERN_INFO "fb%d: Open Firmware frame buffer device on %s\n",
               info->node, full_name);
}


static void __init offb_init_nodriver(struct device_node *dp, int no_real_node)
{
        unsigned int len;
        int i, width = 640, height = 480, depth = 8, pitch = 640;
        unsigned int flags, rsize, addr_prop = 0;
        unsigned long max_size = 0;
        u64 rstart, address = OF_BAD_ADDR;
        const u32 *pp, *addrp, *up;
        u64 asize;

        pp = of_get_property(dp, "linux,bootx-depth", &len);
        if (pp == NULL)
                pp = of_get_property(dp, "depth", &len);
        if (pp && len == sizeof(u32))
                depth = *pp;

        pp = of_get_property(dp, "linux,bootx-width", &len);
        if (pp == NULL)
                pp = of_get_property(dp, "width", &len);
        if (pp && len == sizeof(u32))
                width = *pp;

        pp = of_get_property(dp, "linux,bootx-height", &len);
        if (pp == NULL)
                pp = of_get_property(dp, "height", &len);
        if (pp && len == sizeof(u32))
                height = *pp;

        pp = of_get_property(dp, "linux,bootx-linebytes", &len);
        if (pp == NULL)
                pp = of_get_property(dp, "linebytes", &len);
        if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
                pitch = *pp;
        else
                pitch = width * ((depth + 7) / 8);

        rsize = (unsigned long)pitch * (unsigned long)height;

        /* Ok, now we try to figure out the address of the framebuffer.
         *
         * Unfortunately, Open Firmware doesn't provide a standard way to do
         * so. All we can do is a dodgy heuristic that happens to work in
         * practice. On most machines, the "address" property contains what
         * we need, though not on Matrox cards found in IBM machines. What I've
         * found that appears to give good results is to go through the PCI
         * ranges and pick one that is both big enough and if possible encloses
         * the "address" property. If none match, we pick the biggest
         */
        up = of_get_property(dp, "linux,bootx-addr", &len);
        if (up == NULL)
                up = of_get_property(dp, "address", &len);
        if (up && len == sizeof(u32))
                addr_prop = *up;

        /* Hack for when BootX is passing us */
        if (no_real_node)
                goto skip_addr;

        for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
                     != NULL; i++) {
                int match_addrp = 0;

                if (!(flags & IORESOURCE_MEM))
                        continue;
                if (asize < rsize)
                        continue;
                rstart = of_translate_address(dp, addrp);
                if (rstart == OF_BAD_ADDR)
                        continue;
                if (addr_prop && (rstart <= addr_prop) &&
                    ((rstart + asize) >= (addr_prop + rsize)))
                        match_addrp = 1;
                if (match_addrp) {
                        address = addr_prop;
                        break;
                }
                if (rsize > max_size) {
                        max_size = rsize;
                        address = OF_BAD_ADDR;
                }

                if (address == OF_BAD_ADDR)
                        address = rstart;
        }
 skip_addr:
        if (address == OF_BAD_ADDR && addr_prop)
                address = (u64)addr_prop;
        if (address != OF_BAD_ADDR) {
                /* kludge for valkyrie */
                if (strcmp(dp->name, "valkyrie") == 0)
                        address += 0x1000;
                offb_init_fb(no_real_node ? "bootx" : dp->name,
                             no_real_node ? "display" : dp->full_name,
                             width, height, depth, pitch, address,
                             no_real_node ? NULL : dp);
        }
}

static int __init offb_init(void)
{
        struct device_node *dp = NULL, *boot_disp = NULL;

        if (fb_get_options("offb", NULL))
                return -ENODEV;

        /* Check if we have a MacOS display without a node spec */
        if (of_get_property(of_chosen, "linux,bootx-noscreen", NULL) != NULL) {
                /* The old code tried to work out which node was the MacOS
                 * display based on the address. I'm dropping that since the
                 * lack of a node spec only happens with old BootX versions
                 * (users can update) and with this code, they'll still get
                 * a display (just not the palette hacks).
                 */
                offb_init_nodriver(of_chosen, 1);
        }

        for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
                if (of_get_property(dp, "linux,opened", NULL) &&
                    of_get_property(dp, "linux,boot-display", NULL)) {
                        boot_disp = dp;
                        offb_init_nodriver(dp, 0);
                }
        }
        for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
                if (of_get_property(dp, "linux,opened", NULL) &&
                    dp != boot_disp)
                        offb_init_nodriver(dp, 0);
        }

        return 0;
}


module_init(offb_init);
MODULE_LICENSE("GPL");