/*
 * linux/drivers/video/savagefb.c -- S3 Savage Framebuffer Driver
 *
 * Copyright (c) 2001-2002  Denis Oliver Kropp <dok@directfb.org>
 *                          Sven Neumann <neo@directfb.org>
 *
 *
 * Card specific code is based on XFree86's savage driver.
 * Framebuffer framework code is based on code of cyber2000fb and tdfxfb.
 *
 * 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.
 *
 * 0.4.0 (neo)
 *  - hardware accelerated clear and move
 *
 * 0.3.2 (dok)
 *  - wait for vertical retrace before writing to cr67
 *    at the beginning of savagefb_set_par
 *  - use synchronization registers cr23 and cr26
 *
 * 0.3.1 (dok)
 *  - reset 3D engine
 *  - don't return alpha bits for 32bit format
 *
 * 0.3.0 (dok)
 *  - added WaitIdle functions for all Savage types
 *  - do WaitIdle before mode switching
 *  - code cleanup
 *
 * 0.2.0 (dok)
 *  - first working version
 *
 *
 * TODO
 * - clock validations in decode_var
 *
 * BUGS
 * - white margin on bootup
 *
 */

#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/delay.h>
#include <linux/fb.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/console.h>

#include <asm/io.h>
#include <asm/irq.h>

#include "savagefb.h"


#define SAVAGEFB_VERSION "0.4.0_2.6"

/* --------------------------------------------------------------------- */


static char *mode_option = NULL;

#ifdef MODULE

MODULE_AUTHOR("(c) 2001-2002  Denis Oliver Kropp <dok@directfb.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("FBDev driver for S3 Savage PCI/AGP Chips");

#endif


/* --------------------------------------------------------------------- */

static void vgaHWSeqReset(struct savagefb_par *par, int start)
{
        if (start)
                VGAwSEQ(0x00, 0x01, par);       /* Synchronous Reset */
        else
                VGAwSEQ(0x00, 0x03, par);       /* End Reset */
}

static void vgaHWProtect(struct savagefb_par *par, int on)
{
        unsigned char tmp;

        if (on) {
                /*
                 * Turn off screen and disable sequencer.
                 */
                tmp = VGArSEQ(0x01, par);

                vgaHWSeqReset(par, 1);          /* start synchronous reset */
                VGAwSEQ(0x01, tmp | 0x20, par);/* disable the display */

                VGAenablePalette(par);
        } else {
                /*
                 * Reenable sequencer, then turn on screen.
                 */

                tmp = VGArSEQ(0x01, par);

                VGAwSEQ(0x01, tmp & ~0x20, par);/* reenable display */
                vgaHWSeqReset(par, 0);          /* clear synchronous reset */

                VGAdisablePalette(par);
        }
}

static void vgaHWRestore(struct savagefb_par  *par, struct savage_reg *reg)
{
        int i;

        VGAwMISC(reg->MiscOutReg, par);

        for (i = 1; i < 5; i++)
                VGAwSEQ(i, reg->Sequencer[i], par);

        /* Ensure CRTC registers 0-7 are unlocked by clearing bit 7 or
           CRTC[17] */
        VGAwCR(17, reg->CRTC[17] & ~0x80, par);

        for (i = 0; i < 25; i++)
                VGAwCR(i, reg->CRTC[i], par);

        for (i = 0; i < 9; i++)
                VGAwGR(i, reg->Graphics[i], par);

        VGAenablePalette(par);

        for (i = 0; i < 21; i++)
                VGAwATTR(i, reg->Attribute[i], par);

        VGAdisablePalette(par);
}

static void vgaHWInit(struct fb_var_screeninfo *var,
                      struct savagefb_par            *par,
                      struct xtimings                *timings,
                      struct savage_reg              *reg)
{
        reg->MiscOutReg = 0x23;

        if (!(timings->sync & FB_SYNC_HOR_HIGH_ACT))
                reg->MiscOutReg |= 0x40;

        if (!(timings->sync & FB_SYNC_VERT_HIGH_ACT))
                reg->MiscOutReg |= 0x80;

        /*
         * Time Sequencer
         */
        reg->Sequencer[0x00] = 0x00;
        reg->Sequencer[0x01] = 0x01;
        reg->Sequencer[0x02] = 0x0F;
        reg->Sequencer[0x03] = 0x00;          /* Font select */
        reg->Sequencer[0x04] = 0x0E;          /* Misc */

        /*
         * CRTC Controller
         */
        reg->CRTC[0x00] = (timings->HTotal >> 3) - 5;
        reg->CRTC[0x01] = (timings->HDisplay >> 3) - 1;
        reg->CRTC[0x02] = (timings->HSyncStart >> 3) - 1;
        reg->CRTC[0x03] = (((timings->HSyncEnd >> 3)  - 1) & 0x1f) | 0x80;
        reg->CRTC[0x04] = (timings->HSyncStart >> 3);
        reg->CRTC[0x05] = ((((timings->HSyncEnd >> 3) - 1) & 0x20) << 2) |
                (((timings->HSyncEnd >> 3)) & 0x1f);
        reg->CRTC[0x06] = (timings->VTotal - 2) & 0xFF;
        reg->CRTC[0x07] = (((timings->VTotal - 2) & 0x100) >> 8) |
                (((timings->VDisplay - 1) & 0x100) >> 7) |
                ((timings->VSyncStart & 0x100) >> 6) |
                (((timings->VSyncStart - 1) & 0x100) >> 5) |
                0x10 |
                (((timings->VTotal - 2) & 0x200) >> 4) |
                (((timings->VDisplay - 1) & 0x200) >> 3) |
                ((timings->VSyncStart & 0x200) >> 2);
        reg->CRTC[0x08] = 0x00;
        reg->CRTC[0x09] = (((timings->VSyncStart - 1) & 0x200) >> 4) | 0x40;

        if (timings->dblscan)
                reg->CRTC[0x09] |= 0x80;

        reg->CRTC[0x0a] = 0x00;
        reg->CRTC[0x0b] = 0x00;
        reg->CRTC[0x0c] = 0x00;
        reg->CRTC[0x0d] = 0x00;
        reg->CRTC[0x0e] = 0x00;
        reg->CRTC[0x0f] = 0x00;
        reg->CRTC[0x10] = timings->VSyncStart & 0xff;
        reg->CRTC[0x11] = (timings->VSyncEnd & 0x0f) | 0x20;
        reg->CRTC[0x12] = (timings->VDisplay - 1) & 0xff;
        reg->CRTC[0x13] = var->xres_virtual >> 4;
        reg->CRTC[0x14] = 0x00;
        reg->CRTC[0x15] = (timings->VSyncStart - 1) & 0xff;
        reg->CRTC[0x16] = (timings->VSyncEnd - 1) & 0xff;
        reg->CRTC[0x17] = 0xc3;
        reg->CRTC[0x18] = 0xff;

        /*
         * are these unnecessary?
         * vgaHWHBlankKGA(mode, regp, 0, KGA_FIX_OVERSCAN|KGA_ENABLE_ON_ZERO);
         * vgaHWVBlankKGA(mode, regp, 0, KGA_FIX_OVERSCAN|KGA_ENABLE_ON_ZERO);
         */

        /*
         * Graphics Display Controller
         */
        reg->Graphics[0x00] = 0x00;
        reg->Graphics[0x01] = 0x00;
        reg->Graphics[0x02] = 0x00;
        reg->Graphics[0x03] = 0x00;
        reg->Graphics[0x04] = 0x00;
        reg->Graphics[0x05] = 0x40;
        reg->Graphics[0x06] = 0x05;   /* only map 64k VGA memory !!!! */
        reg->Graphics[0x07] = 0x0F;
        reg->Graphics[0x08] = 0xFF;


        reg->Attribute[0x00]  = 0x00; /* standard colormap translation */
        reg->Attribute[0x01]  = 0x01;
        reg->Attribute[0x02]  = 0x02;
        reg->Attribute[0x03]  = 0x03;
        reg->Attribute[0x04]  = 0x04;
        reg->Attribute[0x05]  = 0x05;
        reg->Attribute[0x06]  = 0x06;
        reg->Attribute[0x07]  = 0x07;
        reg->Attribute[0x08]  = 0x08;
        reg->Attribute[0x09]  = 0x09;
        reg->Attribute[0x0a] = 0x0A;
        reg->Attribute[0x0b] = 0x0B;
        reg->Attribute[0x0c] = 0x0C;
        reg->Attribute[0x0d] = 0x0D;
        reg->Attribute[0x0e] = 0x0E;
        reg->Attribute[0x0f] = 0x0F;
        reg->Attribute[0x10] = 0x41;
        reg->Attribute[0x11] = 0xFF;
        reg->Attribute[0x12] = 0x0F;
        reg->Attribute[0x13] = 0x00;
        reg->Attribute[0x14] = 0x00;
}

/* -------------------- Hardware specific routines ------------------------- */

/*
 * Hardware Acceleration for SavageFB
 */

/* Wait for fifo space */
static void
savage3D_waitfifo(struct savagefb_par *par, int space)
{
        int slots = MAXFIFO - space;

        while ((savage_in32(0x48C00, par) & 0x0000ffff) > slots);
}

static void
savage4_waitfifo(struct savagefb_par *par, int space)
{
        int slots = MAXFIFO - space;

        while ((savage_in32(0x48C60, par) & 0x001fffff) > slots);
}

static void
savage2000_waitfifo(struct savagefb_par *par, int space)
{
        int slots = MAXFIFO - space;

        while ((savage_in32(0x48C60, par) & 0x0000ffff) > slots);
}

/* Wait for idle accelerator */
static void
savage3D_waitidle(struct savagefb_par *par)
{
        while ((savage_in32(0x48C00, par) & 0x0008ffff) != 0x80000);
}

static void
savage4_waitidle(struct savagefb_par *par)
{
        while ((savage_in32(0x48C60, par) & 0x00a00000) != 0x00a00000);
}

static void
savage2000_waitidle(struct savagefb_par *par)
{
        while ((savage_in32(0x48C60, par) & 0x009fffff));
}

#ifdef CONFIG_FB_SAVAGE_ACCEL
static void
SavageSetup2DEngine(struct savagefb_par  *par)
{
        unsigned long GlobalBitmapDescriptor;

        GlobalBitmapDescriptor = 1 | 8 | BCI_BD_BW_DISABLE;
        BCI_BD_SET_BPP(GlobalBitmapDescriptor, par->depth);
        BCI_BD_SET_STRIDE(GlobalBitmapDescriptor, par->vwidth);

        switch(par->chip) {
        case S3_SAVAGE3D:
        case S3_SAVAGE_MX:
                /* Disable BCI */
                savage_out32(0x48C18, savage_in32(0x48C18, par) & 0x3FF0, par);
                /* Setup BCI command overflow buffer */
                savage_out32(0x48C14,
                             (par->cob_offset >> 11) | (par->cob_index << 29),
                             par);
                /* Program shadow status update. */
                savage_out32(0x48C10, 0x78207220, par);
                savage_out32(0x48C0C, 0, par);
                /* Enable BCI and command overflow buffer */
                savage_out32(0x48C18, savage_in32(0x48C18, par) | 0x0C, par);
                break;
        case S3_SAVAGE4:
        case S3_TWISTER:
        case S3_PROSAVAGE:
        case S3_PROSAVAGEDDR:
        case S3_SUPERSAVAGE:
                /* Disable BCI */
                savage_out32(0x48C18, savage_in32(0x48C18, par) & 0x3FF0, par);
                /* Program shadow status update */
                savage_out32(0x48C10, 0x00700040, par);
                savage_out32(0x48C0C, 0, par);
                /* Enable BCI without the COB */
                savage_out32(0x48C18, savage_in32(0x48C18, par) | 0x08, par);
                break;
        case S3_SAVAGE2000:
                /* Disable BCI */
                savage_out32(0x48C18, 0, par);
                /* Setup BCI command overflow buffer */
                savage_out32(0x48C18,
                             (par->cob_offset >> 7) | (par->cob_index),
                             par);
                /* Disable shadow status update */
                savage_out32(0x48A30, 0, par);
                /* Enable BCI and command overflow buffer */
                savage_out32(0x48C18, savage_in32(0x48C18, par) | 0x00280000,
                             par);
                break;
            default:
                break;
        }
        /* Turn on 16-bit register access. */
        vga_out8(0x3d4, 0x31, par);
        vga_out8(0x3d5, 0x0c, par);

        /* Set stride to use GBD. */
        vga_out8(0x3d4, 0x50, par);
        vga_out8(0x3d5, vga_in8(0x3d5, par) | 0xC1, par);

        /* Enable 2D engine. */
        vga_out8(0x3d4, 0x40, par);
        vga_out8(0x3d5, 0x01, par);

        savage_out32(MONO_PAT_0, ~0, par);
        savage_out32(MONO_PAT_1, ~0, par);

        /* Setup plane masks */
        savage_out32(0x8128, ~0, par); /* enable all write planes */
        savage_out32(0x812C, ~0, par); /* enable all read planes */
        savage_out16(0x8134, 0x27, par);
        savage_out16(0x8136, 0x07, par);

        /* Now set the GBD */
        par->bci_ptr = 0;
        par->SavageWaitFifo(par, 4);

        BCI_SEND(BCI_CMD_SETREG | (1 << 16) | BCI_GBD1);
        BCI_SEND(0);
        BCI_SEND(BCI_CMD_SETREG | (1 << 16) | BCI_GBD2);
        BCI_SEND(GlobalBitmapDescriptor);

        /*
         * I don't know why, sending this twice fixes the initial black screen,
         * prevents X from crashing at least in Toshiba laptops with SavageIX.
         * --Tony
         */
        par->bci_ptr = 0;
        par->SavageWaitFifo(par, 4);

        BCI_SEND(BCI_CMD_SETREG | (1 << 16) | BCI_GBD1);
        BCI_SEND(0);
        BCI_SEND(BCI_CMD_SETREG | (1 << 16) | BCI_GBD2);
        BCI_SEND(GlobalBitmapDescriptor);
}

static void savagefb_set_clip(struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        int cmd;

        cmd = BCI_CMD_NOP | BCI_CMD_CLIP_NEW;
        par->bci_ptr = 0;
        par->SavageWaitFifo(par,3);
        BCI_SEND(cmd);
        BCI_SEND(BCI_CLIP_TL(0, 0));
        BCI_SEND(BCI_CLIP_BR(0xfff, 0xfff));
}
#else
static void SavageSetup2DEngine(struct savagefb_par  *par) {}

#endif

static void SavageCalcClock(long freq, int min_m, int min_n1, int max_n1,
                            int min_n2, int max_n2, long freq_min,
                            long freq_max, unsigned int *mdiv,
                            unsigned int *ndiv, unsigned int *r)
{
        long diff, best_diff;
        unsigned int m;
        unsigned char n1, n2, best_n1=16+2, best_n2=2, best_m=125+2;

        if (freq < freq_min / (1 << max_n2)) {
                printk(KERN_ERR "invalid frequency %ld Khz\n", freq);
                freq = freq_min / (1 << max_n2);
        }
        if (freq > freq_max / (1 << min_n2)) {
                printk(KERN_ERR "invalid frequency %ld Khz\n", freq);
                freq = freq_max / (1 << min_n2);
        }

        /* work out suitable timings */
        best_diff = freq;

        for (n2=min_n2; n2<=max_n2; n2++) {
                for (n1=min_n1+2; n1<=max_n1+2; n1++) {
                        m = (freq * n1 * (1 << n2) + HALF_BASE_FREQ) /
                                BASE_FREQ;
                        if (m < min_m+2 || m > 127+2)
                                continue;
                        if ((m * BASE_FREQ >= freq_min * n1) &&
                            (m * BASE_FREQ <= freq_max * n1)) {
                                diff = freq * (1 << n2) * n1 - BASE_FREQ * m;
                                if (diff < 0)
                                        diff = -diff;
                                if (diff < best_diff) {
                                        best_diff = diff;
                                        best_m = m;
                                        best_n1 = n1;
                                        best_n2 = n2;
                                }
                        }
                }
        }

        *ndiv = best_n1 - 2;
        *r = best_n2;
        *mdiv = best_m - 2;
}

static int common_calc_clock(long freq, int min_m, int min_n1, int max_n1,
                             int min_n2, int max_n2, long freq_min,
                             long freq_max, unsigned char *mdiv,
                             unsigned char *ndiv)
{
        long diff, best_diff;
        unsigned int m;
        unsigned char n1, n2;
        unsigned char best_n1 = 16+2, best_n2 = 2, best_m = 125+2;

        best_diff = freq;

        for (n2 = min_n2; n2 <= max_n2; n2++) {
                for (n1 = min_n1+2; n1 <= max_n1+2; n1++) {
                        m = (freq * n1 * (1 << n2) + HALF_BASE_FREQ) /
                                BASE_FREQ;
                        if (m < min_m + 2 || m > 127+2)
                                continue;
                        if ((m * BASE_FREQ >= freq_min * n1) &&
                            (m * BASE_FREQ <= freq_max * n1)) {
                                diff = freq * (1 << n2) * n1 - BASE_FREQ * m;
                                if (diff < 0)
                                        diff = -diff;
                                if (diff < best_diff) {
                                        best_diff = diff;
                                        best_m = m;
                                        best_n1 = n1;
                                        best_n2 = n2;
                                }
                        }
                }
        }

        if (max_n1 == 63)
                *ndiv = (best_n1 - 2) | (best_n2 << 6);
        else
                *ndiv = (best_n1 - 2) | (best_n2 << 5);

        *mdiv = best_m - 2;

        return 0;
}

#ifdef SAVAGEFB_DEBUG
/* This function is used to debug, it prints out the contents of s3 regs */

static void SavagePrintRegs(struct savagefb_par *par)
{
        unsigned char i;
        int vgaCRIndex = 0x3d4;
        int vgaCRReg = 0x3d5;

        printk(KERN_DEBUG "SR    x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE "
               "xF");

        for (i = 0; i < 0x70; i++) {
                if (!(i % 16))
                        printk(KERN_DEBUG "\nSR%xx ", i >> 4);
                vga_out8(0x3c4, i, par);
                printk(KERN_DEBUG " %02x", vga_in8(0x3c5, par));
        }

        printk(KERN_DEBUG "\n\nCR    x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC "
               "xD xE xF");

        for (i = 0; i < 0xB7; i++) {
                if (!(i % 16))
                        printk(KERN_DEBUG "\nCR%xx ", i >> 4);
                vga_out8(vgaCRIndex, i, par);
                printk(KERN_DEBUG " %02x", vga_in8(vgaCRReg, par));
        }

        printk(KERN_DEBUG "\n\n");
}
#endif

/* --------------------------------------------------------------------- */

static void savage_get_default_par(struct savagefb_par *par, struct savage_reg *reg)
{
        unsigned char cr3a, cr53, cr66;

        vga_out16(0x3d4, 0x4838, par);
        vga_out16(0x3d4, 0xa039, par);
        vga_out16(0x3c4, 0x0608, par);

        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x80, par);
        vga_out8(0x3d4, 0x3a, par);
        cr3a = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3a | 0x80, par);
        vga_out8(0x3d4, 0x53, par);
        cr53 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr53 & 0x7f, par);

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);

        /* unlock extended seq regs */
        vga_out8(0x3c4, 0x08, par);
        reg->SR08 = vga_in8(0x3c5, par);
        vga_out8(0x3c5, 0x06, par);

        /* now save all the extended regs we need */
        vga_out8(0x3d4, 0x31, par);
        reg->CR31 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x32, par);
        reg->CR32 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x34, par);
        reg->CR34 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x36, par);
        reg->CR36 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x3a, par);
        reg->CR3A = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x40, par);
        reg->CR40 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x42, par);
        reg->CR42 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x45, par);
        reg->CR45 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x50, par);
        reg->CR50 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x51, par);
        reg->CR51 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x53, par);
        reg->CR53 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x58, par);
        reg->CR58 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x60, par);
        reg->CR60 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x66, par);
        reg->CR66 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x67, par);
        reg->CR67 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x68, par);
        reg->CR68 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x69, par);
        reg->CR69 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x6f, par);
        reg->CR6F = vga_in8(0x3d5, par);

        vga_out8(0x3d4, 0x33, par);
        reg->CR33 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x86, par);
        reg->CR86 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x88, par);
        reg->CR88 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x90, par);
        reg->CR90 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x91, par);
        reg->CR91 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0xb0, par);
        reg->CRB0 = vga_in8(0x3d5, par) | 0x80;

        /* extended mode timing regs */
        vga_out8(0x3d4, 0x3b, par);
        reg->CR3B = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x3c, par);
        reg->CR3C = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x43, par);
        reg->CR43 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x5d, par);
        reg->CR5D = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x5e, par);
        reg->CR5E = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x65, par);
        reg->CR65 = vga_in8(0x3d5, par);

        /* save seq extended regs for DCLK PLL programming */
        vga_out8(0x3c4, 0x0e, par);
        reg->SR0E = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x0f, par);
        reg->SR0F = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x10, par);
        reg->SR10 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x11, par);
        reg->SR11 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x12, par);
        reg->SR12 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x13, par);
        reg->SR13 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x29, par);
        reg->SR29 = vga_in8(0x3c5, par);

        vga_out8(0x3c4, 0x15, par);
        reg->SR15 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x30, par);
        reg->SR30 = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x18, par);
        reg->SR18 = vga_in8(0x3c5, par);

        /* Save flat panel expansion registers. */
        if (par->chip == S3_SAVAGE_MX) {
                int i;

                for (i = 0; i < 8; i++) {
                        vga_out8(0x3c4, 0x54+i, par);
                        reg->SR54[i] = vga_in8(0x3c5, par);
                }
        }

        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x80, par);
        vga_out8(0x3d4, 0x3a, par);
        cr3a = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3a | 0x80, par);

        /* now save MIU regs */
        if (par->chip != S3_SAVAGE_MX) {
                reg->MMPR0 = savage_in32(FIFO_CONTROL_REG, par);
                reg->MMPR1 = savage_in32(MIU_CONTROL_REG, par);
                reg->MMPR2 = savage_in32(STREAMS_TIMEOUT_REG, par);
                reg->MMPR3 = savage_in32(MISC_TIMEOUT_REG, par);
        }

        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);
        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
}

static void savage_set_default_par(struct savagefb_par *par,
                                struct savage_reg *reg)
{
        unsigned char cr3a, cr53, cr66;

        vga_out16(0x3d4, 0x4838, par);
        vga_out16(0x3d4, 0xa039, par);
        vga_out16(0x3c4, 0x0608, par);

        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x80, par);
        vga_out8(0x3d4, 0x3a, par);
        cr3a = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3a | 0x80, par);
        vga_out8(0x3d4, 0x53, par);
        cr53 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr53 & 0x7f, par);

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);

        /* unlock extended seq regs */
        vga_out8(0x3c4, 0x08, par);
        vga_out8(0x3c5, reg->SR08, par);
        vga_out8(0x3c5, 0x06, par);

        /* now restore all the extended regs we need */
        vga_out8(0x3d4, 0x31, par);
        vga_out8(0x3d5, reg->CR31, par);
        vga_out8(0x3d4, 0x32, par);
        vga_out8(0x3d5, reg->CR32, par);
        vga_out8(0x3d4, 0x34, par);
        vga_out8(0x3d5, reg->CR34, par);
        vga_out8(0x3d4, 0x36, par);
        vga_out8(0x3d5,reg->CR36, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, reg->CR3A, par);
        vga_out8(0x3d4, 0x40, par);
        vga_out8(0x3d5, reg->CR40, par);
        vga_out8(0x3d4, 0x42, par);
        vga_out8(0x3d5, reg->CR42, par);
        vga_out8(0x3d4, 0x45, par);
        vga_out8(0x3d5, reg->CR45, par);
        vga_out8(0x3d4, 0x50, par);
        vga_out8(0x3d5, reg->CR50, par);
        vga_out8(0x3d4, 0x51, par);
        vga_out8(0x3d5, reg->CR51, par);
        vga_out8(0x3d4, 0x53, par);
        vga_out8(0x3d5, reg->CR53, par);
        vga_out8(0x3d4, 0x58, par);
        vga_out8(0x3d5, reg->CR58, par);
        vga_out8(0x3d4, 0x60, par);
        vga_out8(0x3d5, reg->CR60, par);
        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, reg->CR66, par);
        vga_out8(0x3d4, 0x67, par);
        vga_out8(0x3d5, reg->CR67, par);
        vga_out8(0x3d4, 0x68, par);
        vga_out8(0x3d5, reg->CR68, par);
        vga_out8(0x3d4, 0x69, par);
        vga_out8(0x3d5, reg->CR69, par);
        vga_out8(0x3d4, 0x6f, par);
        vga_out8(0x3d5, reg->CR6F, par);

        vga_out8(0x3d4, 0x33, par);
        vga_out8(0x3d5, reg->CR33, par);
        vga_out8(0x3d4, 0x86, par);
        vga_out8(0x3d5, reg->CR86, par);
        vga_out8(0x3d4, 0x88, par);
        vga_out8(0x3d5, reg->CR88, par);
        vga_out8(0x3d4, 0x90, par);
        vga_out8(0x3d5, reg->CR90, par);
        vga_out8(0x3d4, 0x91, par);
        vga_out8(0x3d5, reg->CR91, par);
        vga_out8(0x3d4, 0xb0, par);
        vga_out8(0x3d5, reg->CRB0, par);

        /* extended mode timing regs */
        vga_out8(0x3d4, 0x3b, par);
        vga_out8(0x3d5, reg->CR3B, par);
        vga_out8(0x3d4, 0x3c, par);
        vga_out8(0x3d5, reg->CR3C, par);
        vga_out8(0x3d4, 0x43, par);
        vga_out8(0x3d5, reg->CR43, par);
        vga_out8(0x3d4, 0x5d, par);
        vga_out8(0x3d5, reg->CR5D, par);
        vga_out8(0x3d4, 0x5e, par);
        vga_out8(0x3d5, reg->CR5E, par);
        vga_out8(0x3d4, 0x65, par);
        vga_out8(0x3d5, reg->CR65, par);

        /* save seq extended regs for DCLK PLL programming */
        vga_out8(0x3c4, 0x0e, par);
        vga_out8(0x3c5, reg->SR0E, par);
        vga_out8(0x3c4, 0x0f, par);
        vga_out8(0x3c5, reg->SR0F, par);
        vga_out8(0x3c4, 0x10, par);
        vga_out8(0x3c5, reg->SR10, par);
        vga_out8(0x3c4, 0x11, par);
        vga_out8(0x3c5, reg->SR11, par);
        vga_out8(0x3c4, 0x12, par);
        vga_out8(0x3c5, reg->SR12, par);
        vga_out8(0x3c4, 0x13, par);
        vga_out8(0x3c5, reg->SR13, par);
        vga_out8(0x3c4, 0x29, par);
        vga_out8(0x3c5, reg->SR29, par);

        vga_out8(0x3c4, 0x15, par);
        vga_out8(0x3c5, reg->SR15, par);
        vga_out8(0x3c4, 0x30, par);
        vga_out8(0x3c5, reg->SR30, par);
        vga_out8(0x3c4, 0x18, par);
        vga_out8(0x3c5, reg->SR18, par);

        /* Save flat panel expansion registers. */
        if (par->chip == S3_SAVAGE_MX) {
                int i;

                for (i = 0; i < 8; i++) {
                        vga_out8(0x3c4, 0x54+i, par);
                        vga_out8(0x3c5, reg->SR54[i], par);
                }
        }

        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x80, par);
        vga_out8(0x3d4, 0x3a, par);
        cr3a = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3a | 0x80, par);

        /* now save MIU regs */
        if (par->chip != S3_SAVAGE_MX) {
                savage_out32(FIFO_CONTROL_REG, reg->MMPR0, par);
                savage_out32(MIU_CONTROL_REG, reg->MMPR1, par);
                savage_out32(STREAMS_TIMEOUT_REG, reg->MMPR2, par);
                savage_out32(MISC_TIMEOUT_REG, reg->MMPR3, par);
        }

        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);
        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
}

static void savage_update_var(struct fb_var_screeninfo *var,
                              const struct fb_videomode *modedb)
{
        var->xres = var->xres_virtual = modedb->xres;
        var->yres = modedb->yres;
        if (var->yres_virtual < var->yres)
            var->yres_virtual = var->yres;
        var->xoffset = var->yoffset = 0;
        var->pixclock = modedb->pixclock;
        var->left_margin = modedb->left_margin;
        var->right_margin = modedb->right_margin;
        var->upper_margin = modedb->upper_margin;
        var->lower_margin = modedb->lower_margin;
        var->hsync_len = modedb->hsync_len;
        var->vsync_len = modedb->vsync_len;
        var->sync = modedb->sync;
        var->vmode = modedb->vmode;
}

static int savagefb_check_var(struct fb_var_screeninfo   *var,
                              struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        int memlen, vramlen, mode_valid = 0;

        DBG("savagefb_check_var");

        var->transp.offset = 0;
        var->transp.length = 0;
        switch (var->bits_per_pixel) {
        case 8:
                var->red.offset = var->green.offset =
                        var->blue.offset = 0;
                var->red.length = var->green.length =
                        var->blue.length = var->bits_per_pixel;
                break;
        case 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;
                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;

        default:
                return -EINVAL;
        }

        if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
            !info->monspecs.dclkmax || !fb_validate_mode(var, info))
                mode_valid = 1;

        /* calculate modeline if supported by monitor */
        if (!mode_valid && info->monspecs.gtf) {
                if (!fb_get_mode(FB_MAXTIMINGS, 0, var, info))
                        mode_valid = 1;
        }

        if (!mode_valid) {
                const struct fb_videomode *mode;

                mode = fb_find_best_mode(var, &info->modelist);
                if (mode) {
                        savage_update_var(var, mode);
                        mode_valid = 1;
                }
        }

        if (!mode_valid && info->monspecs.modedb_len)
                return -EINVAL;

        /* Is the mode larger than the LCD panel? */
        if (par->SavagePanelWidth &&
            (var->xres > par->SavagePanelWidth ||
             var->yres > par->SavagePanelHeight)) {
                printk(KERN_INFO "Mode (%dx%d) larger than the LCD panel "
                       "(%dx%d)\n", var->xres,  var->yres,
                       par->SavagePanelWidth,
                       par->SavagePanelHeight);
                return -1;
        }

        if (var->yres_virtual < var->yres)
                var->yres_virtual = var->yres;
        if (var->xres_virtual < var->xres)
                var->xres_virtual = var->xres;

        vramlen = info->fix.smem_len;

        memlen = var->xres_virtual * var->bits_per_pixel *
                var->yres_virtual / 8;
        if (memlen > vramlen) {
                var->yres_virtual = vramlen * 8 /
                        (var->xres_virtual * var->bits_per_pixel);
                memlen = var->xres_virtual * var->bits_per_pixel *
                        var->yres_virtual / 8;
        }

        /* we must round yres/xres down, we already rounded y/xres_virtual up
           if it was possible. We should return -EINVAL, but I disagree */
        if (var->yres_virtual < var->yres)
                var->yres = var->yres_virtual;
        if (var->xres_virtual < var->xres)
                var->xres = var->xres_virtual;
        if (var->xoffset + var->xres > var->xres_virtual)
                var->xoffset = var->xres_virtual - var->xres;
        if (var->yoffset + var->yres > var->yres_virtual)
                var->yoffset = var->yres_virtual - var->yres;

        return 0;
}


static int savagefb_decode_var(struct fb_var_screeninfo   *var,
                               struct savagefb_par        *par,
                               struct savage_reg          *reg)
{
        struct xtimings timings;
        int width, dclk, i, j; /*, refresh; */
        unsigned int m, n, r;
        unsigned char tmp = 0;
        unsigned int pixclock = var->pixclock;

        DBG("savagefb_decode_var");

        memset(&timings, 0, sizeof(timings));

        if (!pixclock) pixclock = 10000;        /* 10ns = 100MHz */
        timings.Clock = 1000000000 / pixclock;
        if (timings.Clock < 1) timings.Clock = 1;
        timings.dblscan = var->vmode & FB_VMODE_DOUBLE;
        timings.interlaced = var->vmode & FB_VMODE_INTERLACED;
        timings.HDisplay = var->xres;
        timings.HSyncStart = timings.HDisplay + var->right_margin;
        timings.HSyncEnd = timings.HSyncStart + var->hsync_len;
        timings.HTotal = timings.HSyncEnd + var->left_margin;
        timings.VDisplay = var->yres;
        timings.VSyncStart = timings.VDisplay + var->lower_margin;
        timings.VSyncEnd = timings.VSyncStart + var->vsync_len;
        timings.VTotal = timings.VSyncEnd + var->upper_margin;
        timings.sync = var->sync;


        par->depth  = var->bits_per_pixel;
        par->vwidth = var->xres_virtual;

        if (var->bits_per_pixel == 16  &&  par->chip == S3_SAVAGE3D) {
                timings.HDisplay *= 2;
                timings.HSyncStart *= 2;
                timings.HSyncEnd *= 2;
                timings.HTotal *= 2;
        }

        /*
         * This will allocate the datastructure and initialize all of the
         * generic VGA registers.
         */
        vgaHWInit(var, par, &timings, reg);

        /* We need to set CR67 whether or not we use the BIOS. */

        dclk = timings.Clock;
        reg->CR67 = 0x00;

        switch(var->bits_per_pixel) {
        case 8:
                if ((par->chip == S3_SAVAGE2000) && (dclk >= 230000))
                        reg->CR67 = 0x10;       /* 8bpp, 2 pixels/clock */
                else
                        reg->CR67 = 0x00;       /* 8bpp, 1 pixel/clock */
                break;
        case 15:
                if (S3_SAVAGE_MOBILE_SERIES(par->chip) ||
                    ((par->chip == S3_SAVAGE2000) && (dclk >= 230000)))
                        reg->CR67 = 0x30;       /* 15bpp, 2 pixel/clock */
                else
                        reg->CR67 = 0x20;       /* 15bpp, 1 pixels/clock */
                break;
        case 16:
                if (S3_SAVAGE_MOBILE_SERIES(par->chip) ||
                   ((par->chip == S3_SAVAGE2000) && (dclk >= 230000)))
                        reg->CR67 = 0x50;       /* 16bpp, 2 pixel/clock */
                else
                        reg->CR67 = 0x40;       /* 16bpp, 1 pixels/clock */
                break;
        case 24:
                reg->CR67 = 0x70;
                break;
        case 32:
                reg->CR67 = 0xd0;
                break;
        }

        /*
         * Either BIOS use is disabled, or we failed to find a suitable
         * match.  Fall back to traditional register-crunching.
         */

        vga_out8(0x3d4, 0x3a, par);
        tmp = vga_in8(0x3d5, par);
        if (1 /*FIXME:psav->pci_burst*/)
                reg->CR3A = (tmp & 0x7f) | 0x15;
        else
                reg->CR3A = tmp | 0x95;

        reg->CR53 = 0x00;
        reg->CR31 = 0x8c;
        reg->CR66 = 0x89;

        vga_out8(0x3d4, 0x58, par);
        reg->CR58 = vga_in8(0x3d5, par) & 0x80;
        reg->CR58 |= 0x13;

        reg->SR15 = 0x03 | 0x80;
        reg->SR18 = 0x00;
        reg->CR43 = reg->CR45 = reg->CR65 = 0x00;

        vga_out8(0x3d4, 0x40, par);
        reg->CR40 = vga_in8(0x3d5, par) & ~0x01;

        reg->MMPR0 = 0x010400;
        reg->MMPR1 = 0x00;
        reg->MMPR2 = 0x0808;
        reg->MMPR3 = 0x08080810;

        SavageCalcClock(dclk, 1, 1, 127, 0, 4, 180000, 360000, &m, &n, &r);
        /* m = 107; n = 4; r = 2; */

        if (par->MCLK <= 0) {
                reg->SR10 = 255;
                reg->SR11 = 255;
        } else {
                common_calc_clock(par->MCLK, 1, 1, 31, 0, 3, 135000, 270000,
                                   &reg->SR11, &reg->SR10);
                /*      reg->SR10 = 80; // MCLK == 286000 */
                /*      reg->SR11 = 125; */
        }

        reg->SR12 = (r << 6) | (n & 0x3f);
        reg->SR13 = m & 0xff;
        reg->SR29 = (r & 4) | (m & 0x100) >> 5 | (n & 0x40) >> 2;

        if (var->bits_per_pixel < 24)
                reg->MMPR0 -= 0x8000;
        else
                reg->MMPR0 -= 0x4000;

        if (timings.interlaced)
                reg->CR42 = 0x20;
        else
                reg->CR42 = 0x00;

        reg->CR34 = 0x10; /* display fifo */

        i = ((((timings.HTotal >> 3) - 5) & 0x100) >> 8) |
                ((((timings.HDisplay >> 3) - 1) & 0x100) >> 7) |
                ((((timings.HSyncStart >> 3) - 1) & 0x100) >> 6) |
                ((timings.HSyncStart & 0x800) >> 7);

        if ((timings.HSyncEnd >> 3) - (timings.HSyncStart >> 3) > 64)
                i |= 0x08;
        if ((timings.HSyncEnd >> 3) - (timings.HSyncStart >> 3) > 32)
                i |= 0x20;

        j = (reg->CRTC[0] + ((i & 0x01) << 8) +
             reg->CRTC[4] + ((i & 0x10) << 4) + 1) / 2;

        if (j - (reg->CRTC[4] + ((i & 0x10) << 4)) < 4) {
                if (reg->CRTC[4] + ((i & 0x10) << 4) + 4 <=
                    reg->CRTC[0] + ((i & 0x01) << 8))
                        j = reg->CRTC[4] + ((i & 0x10) << 4) + 4;
                else
                        j = reg->CRTC[0] + ((i & 0x01) << 8) + 1;
        }

        reg->CR3B = j & 0xff;
        i |= (j & 0x100) >> 2;
        reg->CR3C = (reg->CRTC[0] + ((i & 0x01) << 8)) / 2;
        reg->CR5D = i;
        reg->CR5E = (((timings.VTotal - 2) & 0x400) >> 10) |
                (((timings.VDisplay - 1) & 0x400) >> 9) |
                (((timings.VSyncStart) & 0x400) >> 8) |
                (((timings.VSyncStart) & 0x400) >> 6) | 0x40;
        width = (var->xres_virtual * ((var->bits_per_pixel+7) / 8)) >> 3;
        reg->CR91 = reg->CRTC[19] = 0xff & width;
        reg->CR51 = (0x300 & width) >> 4;
        reg->CR90 = 0x80 | (width >> 8);
        reg->MiscOutReg |= 0x0c;

        /* Set frame buffer description. */

        if (var->bits_per_pixel <= 8)
                reg->CR50 = 0;
        else if (var->bits_per_pixel <= 16)
                reg->CR50 = 0x10;
        else
                reg->CR50 = 0x30;

        if (var->xres_virtual <= 640)
                reg->CR50 |= 0x40;
        else if (var->xres_virtual == 800)
                reg->CR50 |= 0x80;
        else if (var->xres_virtual == 1024)
                reg->CR50 |= 0x00;
        else if (var->xres_virtual == 1152)
                reg->CR50 |= 0x01;
        else if (var->xres_virtual == 1280)
                reg->CR50 |= 0xc0;
        else if (var->xres_virtual == 1600)
                reg->CR50 |= 0x81;
        else
                reg->CR50 |= 0xc1;      /* Use GBD */

        if (par->chip == S3_SAVAGE2000)
                reg->CR33 = 0x08;
        else
                reg->CR33 = 0x20;

        reg->CRTC[0x17] = 0xeb;

        reg->CR67 |= 1;

        vga_out8(0x3d4, 0x36, par);
        reg->CR36 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x68, par);
        reg->CR68 = vga_in8(0x3d5, par);
        reg->CR69 = 0;
        vga_out8(0x3d4, 0x6f, par);
        reg->CR6F = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x86, par);
        reg->CR86 = vga_in8(0x3d5, par);
        vga_out8(0x3d4, 0x88, par);
        reg->CR88 = vga_in8(0x3d5, par) | 0x08;
        vga_out8(0x3d4, 0xb0, par);
        reg->CRB0 = vga_in8(0x3d5, par) | 0x80;

        return 0;
}

/* --------------------------------------------------------------------- */

/*
 *    Set a single color register. Return != 0 for invalid regno.
 */
static int savagefb_setcolreg(unsigned        regno,
                              unsigned        red,
                              unsigned        green,
                              unsigned        blue,
                              unsigned        transp,
                              struct fb_info *info)
{
        struct savagefb_par *par = info->par;

        if (regno >= NR_PALETTE)
                return -EINVAL;

        par->palette[regno].red    = red;
        par->palette[regno].green  = green;
        par->palette[regno].blue   = blue;
        par->palette[regno].transp = transp;

        switch (info->var.bits_per_pixel) {
        case 8:
                vga_out8(0x3c8, regno, par);

                vga_out8(0x3c9, red   >> 10, par);
                vga_out8(0x3c9, green >> 10, par);
                vga_out8(0x3c9, blue  >> 10, par);
                break;

        case 16:
                if (regno < 16)
                        ((u32 *)info->pseudo_palette)[regno] =
                                ((red   & 0xf800)      ) |
                                ((green & 0xfc00) >>  5) |
                                ((blue  & 0xf800) >> 11);
                break;

        case 24:
                if (regno < 16)
                        ((u32 *)info->pseudo_palette)[regno] =
                                ((red    & 0xff00) <<  8) |
                                ((green  & 0xff00)      ) |
                                ((blue   & 0xff00) >>  8);
                break;
        case 32:
                if (regno < 16)
                        ((u32 *)info->pseudo_palette)[regno] =
                                ((transp & 0xff00) << 16) |
                                ((red    & 0xff00) <<  8) |
                                ((green  & 0xff00)      ) |
                                ((blue   & 0xff00) >>  8);
                break;

        default:
                return 1;
        }

        return 0;
}

static void savagefb_set_par_int(struct savagefb_par  *par, struct savage_reg *reg)
{
        unsigned char tmp, cr3a, cr66, cr67;

        DBG("savagefb_set_par_int");

        par->SavageWaitIdle(par);

        vga_out8(0x3c2, 0x23, par);

        vga_out16(0x3d4, 0x4838, par);
        vga_out16(0x3d4, 0xa539, par);
        vga_out16(0x3c4, 0x0608, par);

        vgaHWProtect(par, 1);

        /*
         * Some Savage/MX and /IX systems go nuts when trying to exit the
         * server after WindowMaker has displayed a gradient background.  I
         * haven't been able to find what causes it, but a non-destructive
         * switch to mode 3 here seems to eliminate the issue.
         */

        VerticalRetraceWait(par);
        vga_out8(0x3d4, 0x67, par);
        cr67 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr67/*par->CR67*/ & ~0x0c, par); /* no STREAMS yet */

        vga_out8(0x3d4, 0x23, par);
        vga_out8(0x3d5, 0x00, par);
        vga_out8(0x3d4, 0x26, par);
        vga_out8(0x3d5, 0x00, par);

        /* restore extended regs */
        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, reg->CR66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, reg->CR3A, par);
        vga_out8(0x3d4, 0x31, par);
        vga_out8(0x3d5, reg->CR31, par);
        vga_out8(0x3d4, 0x32, par);
        vga_out8(0x3d5, reg->CR32, par);
        vga_out8(0x3d4, 0x58, par);
        vga_out8(0x3d5, reg->CR58, par);
        vga_out8(0x3d4, 0x53, par);
        vga_out8(0x3d5, reg->CR53 & 0x7f, par);

        vga_out16(0x3c4, 0x0608, par);

        /* Restore DCLK registers. */

        vga_out8(0x3c4, 0x0e, par);
        vga_out8(0x3c5, reg->SR0E, par);
        vga_out8(0x3c4, 0x0f, par);
        vga_out8(0x3c5, reg->SR0F, par);
        vga_out8(0x3c4, 0x29, par);
        vga_out8(0x3c5, reg->SR29, par);
        vga_out8(0x3c4, 0x15, par);
        vga_out8(0x3c5, reg->SR15, par);

        /* Restore flat panel expansion registers. */
        if (par->chip == S3_SAVAGE_MX) {
                int i;

                for (i = 0; i < 8; i++) {
                        vga_out8(0x3c4, 0x54+i, par);
                        vga_out8(0x3c5, reg->SR54[i], par);
                }
        }

        vgaHWRestore (par, reg);

        /* extended mode timing registers */
        vga_out8(0x3d4, 0x53, par);
        vga_out8(0x3d5, reg->CR53, par);
        vga_out8(0x3d4, 0x5d, par);
        vga_out8(0x3d5, reg->CR5D, par);
        vga_out8(0x3d4, 0x5e, par);
        vga_out8(0x3d5, reg->CR5E, par);
        vga_out8(0x3d4, 0x3b, par);
        vga_out8(0x3d5, reg->CR3B, par);
        vga_out8(0x3d4, 0x3c, par);
        vga_out8(0x3d5, reg->CR3C, par);
        vga_out8(0x3d4, 0x43, par);
        vga_out8(0x3d5, reg->CR43, par);
        vga_out8(0x3d4, 0x65, par);
        vga_out8(0x3d5, reg->CR65, par);

        /* restore the desired video mode with cr67 */
        vga_out8(0x3d4, 0x67, par);
        /* following part not present in X11 driver */
        cr67 = vga_in8(0x3d5, par) & 0xf;
        vga_out8(0x3d5, 0x50 | cr67, par);
        mdelay(10);
        vga_out8(0x3d4, 0x67, par);
        /* end of part */
        vga_out8(0x3d5, reg->CR67 & ~0x0c, par);

        /* other mode timing and extended regs */
        vga_out8(0x3d4, 0x34, par);
        vga_out8(0x3d5, reg->CR34, par);
        vga_out8(0x3d4, 0x40, par);
        vga_out8(0x3d5, reg->CR40, par);
        vga_out8(0x3d4, 0x42, par);
        vga_out8(0x3d5, reg->CR42, par);
        vga_out8(0x3d4, 0x45, par);
        vga_out8(0x3d5, reg->CR45, par);
        vga_out8(0x3d4, 0x50, par);
        vga_out8(0x3d5, reg->CR50, par);
        vga_out8(0x3d4, 0x51, par);
        vga_out8(0x3d5, reg->CR51, par);

        /* memory timings */
        vga_out8(0x3d4, 0x36, par);
        vga_out8(0x3d5, reg->CR36, par);
        vga_out8(0x3d4, 0x60, par);
        vga_out8(0x3d5, reg->CR60, par);
        vga_out8(0x3d4, 0x68, par);
        vga_out8(0x3d5, reg->CR68, par);
        vga_out8(0x3d4, 0x69, par);
        vga_out8(0x3d5, reg->CR69, par);
        vga_out8(0x3d4, 0x6f, par);
        vga_out8(0x3d5, reg->CR6F, par);

        vga_out8(0x3d4, 0x33, par);
        vga_out8(0x3d5, reg->CR33, par);
        vga_out8(0x3d4, 0x86, par);
        vga_out8(0x3d5, reg->CR86, par);
        vga_out8(0x3d4, 0x88, par);
        vga_out8(0x3d5, reg->CR88, par);
        vga_out8(0x3d4, 0x90, par);
        vga_out8(0x3d5, reg->CR90, par);
        vga_out8(0x3d4, 0x91, par);
        vga_out8(0x3d5, reg->CR91, par);

        if (par->chip == S3_SAVAGE4) {
                vga_out8(0x3d4, 0xb0, par);
                vga_out8(0x3d5, reg->CRB0, par);
        }

        vga_out8(0x3d4, 0x32, par);
        vga_out8(0x3d5, reg->CR32, par);

        /* unlock extended seq regs */
        vga_out8(0x3c4, 0x08, par);
        vga_out8(0x3c5, 0x06, par);

        /* Restore extended sequencer regs for MCLK. SR10 == 255 indicates
         * that we should leave the default SR10 and SR11 values there.
         */
        if (reg->SR10 != 255) {
                vga_out8(0x3c4, 0x10, par);
                vga_out8(0x3c5, reg->SR10, par);
                vga_out8(0x3c4, 0x11, par);
                vga_out8(0x3c5, reg->SR11, par);
        }

        /* restore extended seq regs for dclk */
        vga_out8(0x3c4, 0x0e, par);
        vga_out8(0x3c5, reg->SR0E, par);
        vga_out8(0x3c4, 0x0f, par);
        vga_out8(0x3c5, reg->SR0F, par);
        vga_out8(0x3c4, 0x12, par);
        vga_out8(0x3c5, reg->SR12, par);
        vga_out8(0x3c4, 0x13, par);
        vga_out8(0x3c5, reg->SR13, par);
        vga_out8(0x3c4, 0x29, par);
        vga_out8(0x3c5, reg->SR29, par);
        vga_out8(0x3c4, 0x18, par);
        vga_out8(0x3c5, reg->SR18, par);

        /* load new m, n pll values for dclk & mclk */
        vga_out8(0x3c4, 0x15, par);
        tmp = vga_in8(0x3c5, par) & ~0x21;

        vga_out8(0x3c5, tmp | 0x03, par);
        vga_out8(0x3c5, tmp | 0x23, par);
        vga_out8(0x3c5, tmp | 0x03, par);
        vga_out8(0x3c5, reg->SR15, par);
        udelay(100);

        vga_out8(0x3c4, 0x30, par);
        vga_out8(0x3c5, reg->SR30, par);
        vga_out8(0x3c4, 0x08, par);
        vga_out8(0x3c5, reg->SR08, par);

        /* now write out cr67 in full, possibly starting STREAMS */
        VerticalRetraceWait(par);
        vga_out8(0x3d4, 0x67, par);
        vga_out8(0x3d5, reg->CR67, par);

        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x80, par);
        vga_out8(0x3d4, 0x3a, par);
        cr3a = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3a | 0x80, par);

        if (par->chip != S3_SAVAGE_MX) {
                VerticalRetraceWait(par);
                savage_out32(FIFO_CONTROL_REG, reg->MMPR0, par);
                par->SavageWaitIdle(par);
                savage_out32(MIU_CONTROL_REG, reg->MMPR1, par);
                par->SavageWaitIdle(par);
                savage_out32(STREAMS_TIMEOUT_REG, reg->MMPR2, par);
                par->SavageWaitIdle(par);
                savage_out32(MISC_TIMEOUT_REG, reg->MMPR3, par);
        }

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66, par);
        vga_out8(0x3d4, 0x3a, par);
        vga_out8(0x3d5, cr3a, par);

        SavageSetup2DEngine(par);
        vgaHWProtect(par, 0);
}

static void savagefb_update_start(struct savagefb_par *par, int base)
{
        /* program the start address registers */
        vga_out16(0x3d4, (base & 0x00ff00) | 0x0c, par);
        vga_out16(0x3d4, ((base & 0x00ff) << 8) | 0x0d, par);
        vga_out8(0x3d4, 0x69, par);
        vga_out8(0x3d5, (base & 0x7f0000) >> 16, par);
}


static void savagefb_set_fix(struct fb_info *info)
{
        info->fix.line_length = info->var.xres_virtual *
                info->var.bits_per_pixel / 8;

        if (info->var.bits_per_pixel == 8) {
                info->fix.visual      = FB_VISUAL_PSEUDOCOLOR;
                info->fix.xpanstep    = 4;
        } else {
                info->fix.visual      = FB_VISUAL_TRUECOLOR;
                info->fix.xpanstep    = 2;
        }

}

static int savagefb_set_par(struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        struct fb_var_screeninfo *var = &info->var;
        int err;

        DBG("savagefb_set_par");
        err = savagefb_decode_var(var, par, &par->state);
        if (err)
                return err;

        if (par->dacSpeedBpp <= 0) {
                if (var->bits_per_pixel > 24)
                        par->dacSpeedBpp = par->clock[3];
                else if (var->bits_per_pixel >= 24)
                        par->dacSpeedBpp = par->clock[2];
                else if ((var->bits_per_pixel > 8) && (var->bits_per_pixel < 24))
                        par->dacSpeedBpp = par->clock[1];
                else if (var->bits_per_pixel <= 8)
                        par->dacSpeedBpp = par->clock[0];
        }

        /* Set ramdac limits */
        par->maxClock = par->dacSpeedBpp;
        par->minClock = 10000;

        savagefb_set_par_int(par, &par->state);
        fb_set_cmap(&info->cmap, info);
        savagefb_set_fix(info);
        savagefb_set_clip(info);

        SavagePrintRegs(par);
        return 0;
}

/*
 *    Pan or Wrap the Display
 */
static int savagefb_pan_display(struct fb_var_screeninfo *var,
                                struct fb_info           *info)
{
        struct savagefb_par *par = info->par;
        int base;

        base = (var->yoffset * info->fix.line_length
             + (var->xoffset & ~1) * ((info->var.bits_per_pixel+7) / 8)) >> 2;

        savagefb_update_start(par, base);
        return 0;
}

static int savagefb_blank(int blank, struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        u8 sr8 = 0, srd = 0;

        if (par->display_type == DISP_CRT) {
                vga_out8(0x3c4, 0x08, par);
                sr8 = vga_in8(0x3c5, par);
                sr8 |= 0x06;
                vga_out8(0x3c5, sr8, par);
                vga_out8(0x3c4, 0x0d, par);
                srd = vga_in8(0x3c5, par);
                srd &= 0x50;

                switch (blank) {
                case FB_BLANK_UNBLANK:
                case FB_BLANK_NORMAL:
                        break;
                case FB_BLANK_VSYNC_SUSPEND:
                        srd |= 0x10;
                        break;
                case FB_BLANK_HSYNC_SUSPEND:
                        srd |= 0x40;
                        break;
                case FB_BLANK_POWERDOWN:
                        srd |= 0x50;
                        break;
                }

                vga_out8(0x3c4, 0x0d, par);
                vga_out8(0x3c5, srd, par);
        }

        if (par->display_type == DISP_LCD ||
            par->display_type == DISP_DFP) {
                switch(blank) {
                case FB_BLANK_UNBLANK:
                case FB_BLANK_NORMAL:
                        vga_out8(0x3c4, 0x31, par); /* SR31 bit 4 - FP enable */
                        vga_out8(0x3c5, vga_in8(0x3c5, par) | 0x10, par);
                        break;
                case FB_BLANK_VSYNC_SUSPEND:
                case FB_BLANK_HSYNC_SUSPEND:
                case FB_BLANK_POWERDOWN:
                        vga_out8(0x3c4, 0x31, par); /* SR31 bit 4 - FP enable */
                        vga_out8(0x3c5, vga_in8(0x3c5, par) & ~0x10, par);
                        break;
                }
        }

        return (blank == FB_BLANK_NORMAL) ? 1 : 0;
}

static int savagefb_open(struct fb_info *info, int user)
{
        struct savagefb_par *par = info->par;

        mutex_lock(&par->open_lock);

        if (!par->open_count) {
                memset(&par->vgastate, 0, sizeof(par->vgastate));
                par->vgastate.flags = VGA_SAVE_CMAP | VGA_SAVE_FONTS |
                        VGA_SAVE_MODE;
                par->vgastate.vgabase = par->mmio.vbase + 0x8000;
                save_vga(&par->vgastate);
                savage_get_default_par(par, &par->initial);
        }

        par->open_count++;
        mutex_unlock(&par->open_lock);
        return 0;
}

static int savagefb_release(struct fb_info *info, int user)
{
        struct savagefb_par *par = info->par;

        mutex_lock(&par->open_lock);

        if (par->open_count == 1) {
                savage_set_default_par(par, &par->initial);
                restore_vga(&par->vgastate);
        }

        par->open_count--;
        mutex_unlock(&par->open_lock);
        return 0;
}

static const struct fb_ops savagefb_ops = {
        .owner          = THIS_MODULE,
        .fb_open        = savagefb_open,
        .fb_release     = savagefb_release,
        .fb_check_var   = savagefb_check_var,
        .fb_set_par     = savagefb_set_par,
        .fb_setcolreg   = savagefb_setcolreg,
        .fb_pan_display = savagefb_pan_display,
        .fb_blank       = savagefb_blank,
#if defined(CONFIG_FB_SAVAGE_ACCEL)
        .fb_fillrect    = savagefb_fillrect,
        .fb_copyarea    = savagefb_copyarea,
        .fb_imageblit   = savagefb_imageblit,
        .fb_sync        = savagefb_sync,
#else
        .fb_fillrect    = cfb_fillrect,
        .fb_copyarea    = cfb_copyarea,
        .fb_imageblit   = cfb_imageblit,
#endif
};

/* --------------------------------------------------------------------- */

static const struct fb_var_screeninfo savagefb_var800x600x8 = {
        .accel_flags =  FB_ACCELF_TEXT,
        .xres =         800,
        .yres =         600,
        .xres_virtual =  800,
        .yres_virtual =  600,
        .bits_per_pixel = 8,
        .pixclock =     25000,
        .left_margin =  88,
        .right_margin = 40,
        .upper_margin = 23,
        .lower_margin = 1,
        .hsync_len =    128,
        .vsync_len =    4,
        .sync =         FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
        .vmode =        FB_VMODE_NONINTERLACED
};

static void savage_enable_mmio(struct savagefb_par *par)
{
        unsigned char val;

        DBG("savage_enable_mmio\n");

        val = vga_in8(0x3c3, par);
        vga_out8(0x3c3, val | 0x01, par);
        val = vga_in8(0x3cc, par);
        vga_out8(0x3c2, val | 0x01, par);

        if (par->chip >= S3_SAVAGE4) {
                vga_out8(0x3d4, 0x40, par);
                val = vga_in8(0x3d5, par);
                vga_out8(0x3d5, val | 1, par);
        }
}


static void savage_disable_mmio(struct savagefb_par *par)
{
        unsigned char val;

        DBG("savage_disable_mmio\n");

        if (par->chip >= S3_SAVAGE4) {
                vga_out8(0x3d4, 0x40, par);
                val = vga_in8(0x3d5, par);
                vga_out8(0x3d5, val | 1, par);
        }
}


static int savage_map_mmio(struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        DBG("savage_map_mmio");

        if (S3_SAVAGE3D_SERIES(par->chip))
                par->mmio.pbase = pci_resource_start(par->pcidev, 0) +
                        SAVAGE_NEWMMIO_REGBASE_S3;
        else
                par->mmio.pbase = pci_resource_start(par->pcidev, 0) +
                        SAVAGE_NEWMMIO_REGBASE_S4;

        par->mmio.len = SAVAGE_NEWMMIO_REGSIZE;

        par->mmio.vbase = ioremap(par->mmio.pbase, par->mmio.len);
        if (!par->mmio.vbase) {
                printk("savagefb: unable to map memory mapped IO\n");
                return -ENOMEM;
        } else
                printk(KERN_INFO "savagefb: mapped io at %p\n",
                        par->mmio.vbase);

        info->fix.mmio_start = par->mmio.pbase;
        info->fix.mmio_len   = par->mmio.len;

        par->bci_base = (u32 __iomem *)(par->mmio.vbase + BCI_BUFFER_OFFSET);
        par->bci_ptr  = 0;

        savage_enable_mmio(par);

        return 0;
}

static void savage_unmap_mmio(struct fb_info *info)
{
        struct savagefb_par *par = info->par;
        DBG("savage_unmap_mmio");

        savage_disable_mmio(par);

        if (par->mmio.vbase) {
                iounmap(par->mmio.vbase);
                par->mmio.vbase = NULL;
        }
}

static int savage_map_video(struct fb_info *info, int video_len)
{
        struct savagefb_par *par = info->par;
        int resource;

        DBG("savage_map_video");

        if (S3_SAVAGE3D_SERIES(par->chip))
                resource = 0;
        else
                resource = 1;

        par->video.pbase = pci_resource_start(par->pcidev, resource);
        par->video.len   = video_len;
        par->video.vbase = ioremap_wc(par->video.pbase, par->video.len);

        if (!par->video.vbase) {
                printk("savagefb: unable to map screen memory\n");
                return -ENOMEM;
        } else
                printk(KERN_INFO "savagefb: mapped framebuffer at %p, "
                       "pbase == %x\n", par->video.vbase, par->video.pbase);

        info->fix.smem_start = par->video.pbase;
        info->fix.smem_len   = par->video.len - par->cob_size;
        info->screen_base    = par->video.vbase;
        par->video.wc_cookie = arch_phys_wc_add(par->video.pbase, video_len);

        /* Clear framebuffer, it's all white in memory after boot */
        memset_io(par->video.vbase, 0, par->video.len);

        return 0;
}

static void savage_unmap_video(struct fb_info *info)
{
        struct savagefb_par *par = info->par;

        DBG("savage_unmap_video");

        if (par->video.vbase) {
                arch_phys_wc_del(par->video.wc_cookie);
                iounmap(par->video.vbase);
                par->video.vbase = NULL;
                info->screen_base = NULL;
        }
}

static int savage_init_hw(struct savagefb_par *par)
{
        unsigned char config1, m, n, n1, n2, sr8, cr3f, cr66 = 0, tmp;

        static unsigned char RamSavage3D[] = { 8, 4, 4, 2 };
        static unsigned char RamSavage4[] =  { 2, 4, 8, 12, 16, 32, 64, 32 };
        static unsigned char RamSavageMX[] = { 2, 8, 4, 16, 8, 16, 4, 16 };
        static unsigned char RamSavageNB[] = { 0, 2, 4, 8, 16, 32, 2, 2 };
        int videoRam, videoRambytes, dvi;

        DBG("savage_init_hw");

        /* unprotect CRTC[0-7] */
        vga_out8(0x3d4, 0x11, par);
        tmp = vga_in8(0x3d5, par);
        vga_out8(0x3d5, tmp & 0x7f, par);

        /* unlock extended regs */
        vga_out16(0x3d4, 0x4838, par);
        vga_out16(0x3d4, 0xa039, par);
        vga_out16(0x3c4, 0x0608, par);

        vga_out8(0x3d4, 0x40, par);
        tmp = vga_in8(0x3d5, par);
        vga_out8(0x3d5, tmp & ~0x01, par);

        /* unlock sys regs */
        vga_out8(0x3d4, 0x38, par);
        vga_out8(0x3d5, 0x48, par);

        /* Unlock system registers. */
        vga_out16(0x3d4, 0x4838, par);

        /* Next go on to detect amount of installed ram */

        vga_out8(0x3d4, 0x36, par);            /* for register CR36 (CONFG_REG1), */
        config1 = vga_in8(0x3d5, par);    /* get amount of vram installed */

        /* Compute the amount of video memory and offscreen memory. */

        switch  (par->chip) {
        case S3_SAVAGE3D:
                videoRam = RamSavage3D[(config1 & 0xC0) >> 6 ] * 1024;
                break;

        case S3_SAVAGE4:
                /*
                 * The Savage4 has one ugly special case to consider.  On
                 * systems with 4 banks of 2Mx32 SDRAM, the BIOS says 4MB
                 * when it really means 8MB.  Why do it the same when you
                 * can do it different...
                 */
                vga_out8(0x3d4, 0x68, par);     /* memory control 1 */
                if ((vga_in8(0x3d5, par) & 0xC0) == (0x01 << 6))
                        RamSavage4[1] = 8;
                fallthrough;

        case S3_SAVAGE2000:
                videoRam = RamSavage4[(config1 & 0xE0) >> 5] * 1024;
                break;

        case S3_SAVAGE_MX:
        case S3_SUPERSAVAGE:
                videoRam = RamSavageMX[(config1 & 0x0E) >> 1] * 1024;
                break;

        case S3_PROSAVAGE:
        case S3_PROSAVAGEDDR:
        case S3_TWISTER:
                videoRam = RamSavageNB[(config1 & 0xE0) >> 5] * 1024;
                break;

        default:
                /* How did we get here? */
                videoRam = 0;
                break;
        }

        videoRambytes = videoRam * 1024;

        printk(KERN_INFO "savagefb: probed videoram:  %dk\n", videoRam);

        /* reset graphics engine to avoid memory corruption */
        vga_out8(0x3d4, 0x66, par);
        cr66 = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr66 | 0x02, par);
        usleep_range(10000, 11000);

        vga_out8(0x3d4, 0x66, par);
        vga_out8(0x3d5, cr66 & ~0x02, par);     /* clear reset flag */
        usleep_range(10000, 11000);


        /*
         * reset memory interface, 3D engine, AGP master, PCI master,
         * master engine unit, motion compensation/LPB
         */
        vga_out8(0x3d4, 0x3f, par);
        cr3f = vga_in8(0x3d5, par);
        vga_out8(0x3d5, cr3f | 0x08, par);
        usleep_range(10000, 11000);

        vga_out8(0x3d4, 0x3f, par);
        vga_out8(0x3d5, cr3f & ~0x08, par);     /* clear reset flags */
        usleep_range(10000, 11000);

        /* Savage ramdac speeds */
        par->numClocks = 4;
        par->clock[0] = 250000;
        par->clock[1] = 250000;
        par->clock[2] = 220000;
        par->clock[3] = 220000;

        /* detect current mclk */
        vga_out8(0x3c4, 0x08, par);
        sr8 = vga_in8(0x3c5, par);
        vga_out8(0x3c5, 0x06, par);
        vga_out8(0x3c4, 0x10, par);
        n = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x11, par);
        m = vga_in8(0x3c5, par);
        vga_out8(0x3c4, 0x08, par);
        vga_out8(0x3c5, sr8, par);
        m &= 0x7f;
        n1 = n & 0x1f;
        n2 = (n >> 5) & 0x03;
        par->MCLK = ((1431818 * (m+2)) / (n1+2) / (1 << n2) + 50) / 100;
        printk(KERN_INFO "savagefb: Detected current MCLK value of %d kHz\n",
                par->MCLK);

        /* check for DVI/flat panel */
        dvi = 0;

        if (par->chip == S3_SAVAGE4) {
                unsigned char sr30 = 0x00;

                vga_out8(0x3c4, 0x30, par);
                /* clear bit 1 */
                vga_out8(0x3c5, vga_in8(0x3c5, par) & ~0x02, par);
                sr30 = vga_in8(0x3c5, par);
                if (sr30 & 0x02 /*0x04 */) {
                        dvi = 1;
                        printk("savagefb: Digital Flat Panel Detected\n");
                }
        }

        if ((S3_SAVAGE_MOBILE_SERIES(par->chip) ||
             S3_MOBILE_TWISTER_SERIES(par->chip)) && !par->crtonly)
                par->display_type = DISP_LCD;
        else if (dvi || (par->chip == S3_SAVAGE4 && par->dvi))
                par->display_type = DISP_DFP;
        else
                par->display_type = DISP_CRT;

        /* Check LCD panel parrmation */

        if (par->display_type == DISP_LCD) {
                unsigned char cr6b = VGArCR(0x6b, par);

                int panelX = (VGArSEQ(0x61, par) +
                              ((VGArSEQ(0x66, par) & 0x02) << 7) + 1) * 8;
                int panelY = (VGArSEQ(0x69, par) +
                              ((VGArSEQ(0x6e, par) & 0x70) << 4) + 1);

                char * sTechnology = "Unknown";

                /* OK, I admit it.  I don't know how to limit the max dot clock
                 * for LCD panels of various sizes.  I thought I copied the
                 * formula from the BIOS, but many users have parrmed me of
                 * my folly.
                 *
                 * Instead, I'll abandon any attempt to automatically limit the
                 * clock, and add an LCDClock option to XF86Config.  Some day,
                 * I should come back to this.
                 */

                enum ACTIVE_DISPLAYS { /* These are the bits in CR6B */
                        ActiveCRT = 0x01,
                        ActiveLCD = 0x02,
                        ActiveTV = 0x04,
                        ActiveCRT2 = 0x20,
                        ActiveDUO = 0x80
                };

                if ((VGArSEQ(0x39, par) & 0x03) == 0) {
                        sTechnology = "TFT";
                } else if ((VGArSEQ(0x30, par) & 0x01) == 0) {
                        sTechnology = "DSTN";
                } else  {
                        sTechnology = "STN";
                }

                printk(KERN_INFO "savagefb: %dx%d %s LCD panel detected %s\n",
                       panelX, panelY, sTechnology,

                       cr6b & ActiveLCD ? "and active" : "but not active");

                if (cr6b & ActiveLCD)   {
                        /*
                         * If the LCD is active and panel expansion is enabled,
                         * we probably want to kill the HW cursor.
                         */

                        printk(KERN_INFO "savagefb: Limiting video mode to "
                                "%dx%d\n", panelX, panelY);

                        par->SavagePanelWidth = panelX;
                        par->SavagePanelHeight = panelY;

                } else
                        par->display_type = DISP_CRT;
        }

        savage_get_default_par(par, &par->state);
        par->save = par->state;

        if (S3_SAVAGE4_SERIES(par->chip)) {
                /*
                 * The Savage4 and ProSavage have COB coherency bugs which
                 * render the buffer useless.  We disable it.
                 */
                par->cob_index = 2;
                par->cob_size = 0x8000 << par->cob_index;
                par->cob_offset = videoRambytes;
        } else {
                /* We use 128kB for the COB on all chips. */

                par->cob_index  = 7;
                par->cob_size   = 0x400 << par->cob_index;
                par->cob_offset = videoRambytes - par->cob_size;
        }

        return videoRambytes;
}

static int savage_init_fb_info(struct fb_info *info, struct pci_dev *dev,
                               const struct pci_device_id *id)
{
        struct savagefb_par *par = info->par;
        int err = 0;

        par->pcidev  = dev;

        info->fix.type     = FB_TYPE_PACKED_PIXELS;
        info->fix.type_aux         = 0;
        info->fix.ypanstep         = 1;
        info->fix.ywrapstep   = 0;
        info->fix.accel       = id->driver_data;

        switch (info->fix.accel) {
        case FB_ACCEL_SUPERSAVAGE:
                par->chip = S3_SUPERSAVAGE;
                snprintf(info->fix.id, 16, "SuperSavage");
                break;
        case FB_ACCEL_SAVAGE4:
                par->chip = S3_SAVAGE4;
                snprintf(info->fix.id, 16, "Savage4");
                break;
        case FB_ACCEL_SAVAGE3D:
                par->chip = S3_SAVAGE3D;
                snprintf(info->fix.id, 16, "Savage3D");
                break;
        case FB_ACCEL_SAVAGE3D_MV:
                par->chip = S3_SAVAGE3D;
                snprintf(info->fix.id, 16, "Savage3D-MV");
                break;
        case FB_ACCEL_SAVAGE2000:
                par->chip = S3_SAVAGE2000;
                snprintf(info->fix.id, 16, "Savage2000");
                break;
        case FB_ACCEL_SAVAGE_MX_MV:
                par->chip = S3_SAVAGE_MX;
                snprintf(info->fix.id, 16, "Savage/MX-MV");
                break;
        case FB_ACCEL_SAVAGE_MX:
                par->chip = S3_SAVAGE_MX;
                snprintf(info->fix.id, 16, "Savage/MX");
                break;
        case FB_ACCEL_SAVAGE_IX_MV:
                par->chip = S3_SAVAGE_MX;
                snprintf(info->fix.id, 16, "Savage/IX-MV");
                break;
        case FB_ACCEL_SAVAGE_IX:
                par->chip = S3_SAVAGE_MX;
                snprintf(info->fix.id, 16, "Savage/IX");
                break;
        case FB_ACCEL_PROSAVAGE_PM:
                par->chip = S3_PROSAVAGE;
                snprintf(info->fix.id, 16, "ProSavagePM");
                break;
        case FB_ACCEL_PROSAVAGE_KM:
                par->chip = S3_PROSAVAGE;
                snprintf(info->fix.id, 16, "ProSavageKM");
                break;
        case FB_ACCEL_S3TWISTER_P:
                par->chip = S3_TWISTER;
                snprintf(info->fix.id, 16, "TwisterP");
                break;
        case FB_ACCEL_S3TWISTER_K:
                par->chip = S3_TWISTER;
                snprintf(info->fix.id, 16, "TwisterK");
                break;
        case FB_ACCEL_PROSAVAGE_DDR:
                par->chip = S3_PROSAVAGEDDR;
                snprintf(info->fix.id, 16, "ProSavageDDR");
                break;
        case FB_ACCEL_PROSAVAGE_DDRK:
                par->chip = S3_PROSAVAGEDDR;
                snprintf(info->fix.id, 16, "ProSavage8");
                break;
        }

        if (S3_SAVAGE3D_SERIES(par->chip)) {
                par->SavageWaitIdle = savage3D_waitidle;
                par->SavageWaitFifo = savage3D_waitfifo;
        } else if (S3_SAVAGE4_SERIES(par->chip) ||
                   S3_SUPERSAVAGE == par->chip) {
                par->SavageWaitIdle = savage4_waitidle;
                par->SavageWaitFifo = savage4_waitfifo;
        } else {
                par->SavageWaitIdle = savage2000_waitidle;
                par->SavageWaitFifo = savage2000_waitfifo;
        }

        info->var.nonstd      = 0;
        info->var.activate    = FB_ACTIVATE_NOW;
        info->var.width       = -1;
        info->var.height      = -1;
        info->var.accel_flags = 0;

        info->fbops          = &savagefb_ops;
        info->flags          = FBINFO_DEFAULT |
                               FBINFO_HWACCEL_YPAN |
                               FBINFO_HWACCEL_XPAN;

        info->pseudo_palette = par->pseudo_palette;

#if defined(CONFIG_FB_SAVAGE_ACCEL)
        /* FIFO size + padding for commands */
        info->pixmap.addr = kcalloc(8, 1024, GFP_KERNEL);

        err = -ENOMEM;
        if (info->pixmap.addr) {
                info->pixmap.size = 8*1024;
                info->pixmap.scan_align = 4;
                info->pixmap.buf_align = 4;
                info->pixmap.access_align = 32;

                err = fb_alloc_cmap(&info->cmap, NR_PALETTE, 0);
                if (!err)
                        info->flags |= FBINFO_HWACCEL_COPYAREA |
                                       FBINFO_HWACCEL_FILLRECT |
                                       FBINFO_HWACCEL_IMAGEBLIT;
                else
                        kfree(info->pixmap.addr);
        }
#endif
        return err;
}

/* --------------------------------------------------------------------- */

static int savagefb_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
        struct fb_info *info;
        struct savagefb_par *par;
        u_int h_sync, v_sync;
        int err, lpitch;
        int video_len;

        DBG("savagefb_probe");

        info = framebuffer_alloc(sizeof(struct savagefb_par), &dev->dev);
        if (!info)
                return -ENOMEM;
        par = info->par;
        mutex_init(&par->open_lock);
        err = pci_enable_device(dev);
        if (err)
                goto failed_enable;

        if ((err = pci_request_regions(dev, "savagefb"))) {
                printk(KERN_ERR "cannot request PCI regions\n");
                goto failed_enable;
        }

        err = -ENOMEM;

        if ((err = savage_init_fb_info(info, dev, id)))
                goto failed_init;

        err = savage_map_mmio(info);
        if (err)
                goto failed_mmio;

        video_len = savage_init_hw(par);
        /* FIXME: can't be negative */
        if (video_len < 0) {
                err = video_len;
                goto failed_mmio;
        }

        err = savage_map_video(info, video_len);
        if (err)
                goto failed_video;

        INIT_LIST_HEAD(&info->modelist);
#if defined(CONFIG_FB_SAVAGE_I2C)
        savagefb_create_i2c_busses(info);
        savagefb_probe_i2c_connector(info, &par->edid);
        fb_edid_to_monspecs(par->edid, &info->monspecs);
        kfree(par->edid);
        fb_videomode_to_modelist(info->monspecs.modedb,
                                 info->monspecs.modedb_len,
                                 &info->modelist);
#endif
        info->var = savagefb_var800x600x8;
        /* if a panel was detected, default to a CVT mode instead */
        if (par->SavagePanelWidth) {
                struct fb_videomode cvt_mode;

                memset(&cvt_mode, 0, sizeof(cvt_mode));
                cvt_mode.xres = par->SavagePanelWidth;
                cvt_mode.yres = par->SavagePanelHeight;
                cvt_mode.refresh = 60;
                /* FIXME: if we know there is only the panel
                 * we can enable reduced blanking as well */
                if (fb_find_mode_cvt(&cvt_mode, 0, 0))
                        printk(KERN_WARNING "No CVT mode found for panel\n");
                else if (fb_find_mode(&info->var, info, NULL, NULL, 0,
                                      &cvt_mode, 0) != 3)
                        info->var = savagefb_var800x600x8;
        }

        if (mode_option) {
                fb_find_mode(&info->var, info, mode_option,
                             info->monspecs.modedb, info->monspecs.modedb_len,
                             NULL, 8);
        } else if (info->monspecs.modedb != NULL) {
                const struct fb_videomode *mode;

                mode = fb_find_best_display(&info->monspecs, &info->modelist);
                savage_update_var(&info->var, mode);
        }

        /* maximize virtual vertical length */
        lpitch = info->var.xres_virtual*((info->var.bits_per_pixel + 7) >> 3);
        info->var.yres_virtual = info->fix.smem_len/lpitch;

        if (info->var.yres_virtual < info->var.yres) {
                err = -ENOMEM;
                goto failed;
        }

#if defined(CONFIG_FB_SAVAGE_ACCEL)
        /*
         * The clipping coordinates are masked with 0xFFF, so limit our
         * virtual resolutions to these sizes.
         */
        if (info->var.yres_virtual > 0x1000)
                info->var.yres_virtual = 0x1000;

        if (info->var.xres_virtual > 0x1000)
                info->var.xres_virtual = 0x1000;
#endif
        savagefb_check_var(&info->var, info);
        savagefb_set_fix(info);

        /*
         * Calculate the hsync and vsync frequencies.  Note that
         * we split the 1e12 constant up so that we can preserve
         * the precision and fit the results into 32-bit registers.
         *  (1953125000 * 512 = 1e12)
         */
        h_sync = 1953125000 / info->var.pixclock;
        h_sync = h_sync * 512 / (info->var.xres + info->var.left_margin +
                                 info->var.right_margin +
                                 info->var.hsync_len);
        v_sync = h_sync / (info->var.yres + info->var.upper_margin +
                           info->var.lower_margin + info->var.vsync_len);

        printk(KERN_INFO "savagefb v" SAVAGEFB_VERSION ": "
               "%dkB VRAM, using %dx%d, %d.%03dkHz, %dHz\n",
               info->fix.smem_len >> 10,
               info->var.xres, info->var.yres,
               h_sync / 1000, h_sync % 1000, v_sync);


        fb_destroy_modedb(info->monspecs.modedb);
        info->monspecs.modedb = NULL;

        err = register_framebuffer(info);
        if (err < 0)
                goto failed;

        printk(KERN_INFO "fb: S3 %s frame buffer device\n",
               info->fix.id);

        /*
         * Our driver data
         */
        pci_set_drvdata(dev, info);

        return 0;

 failed:
#ifdef CONFIG_FB_SAVAGE_I2C
        savagefb_delete_i2c_busses(info);
#endif
        fb_alloc_cmap(&info->cmap, 0, 0);
        savage_unmap_video(info);
 failed_video:
        savage_unmap_mmio(info);
 failed_mmio:
        kfree(info->pixmap.addr);
 failed_init:
        pci_release_regions(dev);
 failed_enable:
        framebuffer_release(info);

        return err;
}

static void savagefb_remove(struct pci_dev *dev)
{
        struct fb_info *info = pci_get_drvdata(dev);

        DBG("savagefb_remove");

        if (info) {
                unregister_framebuffer(info);

#ifdef CONFIG_FB_SAVAGE_I2C
                savagefb_delete_i2c_busses(info);
#endif
                fb_alloc_cmap(&info->cmap, 0, 0);
                savage_unmap_video(info);
                savage_unmap_mmio(info);
                kfree(info->pixmap.addr);
                pci_release_regions(dev);
                framebuffer_release(info);
        }
}

static int savagefb_suspend_late(struct device *dev, pm_message_t mesg)
{
        struct fb_info *info = dev_get_drvdata(dev);
        struct savagefb_par *par = info->par;

        DBG("savagefb_suspend");

        if (mesg.event == PM_EVENT_PRETHAW)
                mesg.event = PM_EVENT_FREEZE;
        par->pm_state = mesg.event;
        dev->power.power_state = mesg;

        /*
         * For PM_EVENT_FREEZE, do not power down so the console
         * can remain active.
         */
        if (mesg.event == PM_EVENT_FREEZE)
                return 0;

        console_lock();
        fb_set_suspend(info, 1);

        if (info->fbops->fb_sync)
                info->fbops->fb_sync(info);

        savagefb_blank(FB_BLANK_POWERDOWN, info);
        savage_set_default_par(par, &par->save);
        savage_disable_mmio(par);
        console_unlock();

        return 0;
}

static int __maybe_unused savagefb_suspend(struct device *dev)
{
        return savagefb_suspend_late(dev, PMSG_SUSPEND);
}

static int __maybe_unused savagefb_hibernate(struct device *dev)
{
        return savagefb_suspend_late(dev, PMSG_HIBERNATE);
}

static int __maybe_unused savagefb_freeze(struct device *dev)
{
        return savagefb_suspend_late(dev, PMSG_FREEZE);
}

static int __maybe_unused savagefb_resume(struct device *dev)
{
        struct fb_info *info = dev_get_drvdata(dev);
        struct savagefb_par *par = info->par;
        int cur_state = par->pm_state;

        DBG("savage_resume");

        par->pm_state = PM_EVENT_ON;

        /*
         * The adapter was not powered down coming back from a
         * PM_EVENT_FREEZE.
         */
        if (cur_state == PM_EVENT_FREEZE)
                return 0;

        console_lock();

        savage_enable_mmio(par);
        savage_init_hw(par);
        savagefb_set_par(info);
        fb_set_suspend(info, 0);
        savagefb_blank(FB_BLANK_UNBLANK, info);
        console_unlock();

        return 0;
}

static const struct dev_pm_ops savagefb_pm_ops = {
#ifdef CONFIG_PM_SLEEP
        .suspend        = savagefb_suspend,
        .resume         = savagefb_resume,
        .freeze         = savagefb_freeze,
        .thaw           = savagefb_resume,
        .poweroff       = savagefb_hibernate,
        .restore        = savagefb_resume,
#endif
};

static const struct pci_device_id savagefb_devices[] = {
        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_MX128,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_MX64,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_MX64C,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IX128SDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IX128DDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IX64SDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IX64DDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IXCSDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SUPSAV_IXCDDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SUPERSAVAGE},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE4,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE4},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE3D,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE3D},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE3D_MV,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE3D_MV},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE2000,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE2000},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE_MX_MV,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE_MX_MV},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE_MX,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE_MX},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE_IX_MV,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE_IX_MV},

        {PCI_VENDOR_ID_S3, PCI_CHIP_SAVAGE_IX,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_SAVAGE_IX},

        {PCI_VENDOR_ID_S3, PCI_CHIP_PROSAVAGE_PM,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_PROSAVAGE_PM},

        {PCI_VENDOR_ID_S3, PCI_CHIP_PROSAVAGE_KM,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_PROSAVAGE_KM},

        {PCI_VENDOR_ID_S3, PCI_CHIP_S3TWISTER_P,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_S3TWISTER_P},

        {PCI_VENDOR_ID_S3, PCI_CHIP_S3TWISTER_K,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_S3TWISTER_K},

        {PCI_VENDOR_ID_S3, PCI_CHIP_PROSAVAGE_DDR,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_PROSAVAGE_DDR},

        {PCI_VENDOR_ID_S3, PCI_CHIP_PROSAVAGE_DDRK,
         PCI_ANY_ID, PCI_ANY_ID, 0, 0, FB_ACCEL_PROSAVAGE_DDRK},

        {0, 0, 0, 0, 0, 0, 0}
};

MODULE_DEVICE_TABLE(pci, savagefb_devices);

static struct pci_driver savagefb_driver = {
        .name =     "savagefb",
        .id_table = savagefb_devices,
        .probe =    savagefb_probe,
        .driver.pm = &savagefb_pm_ops,
        .remove =   savagefb_remove,
};

/* **************************** exit-time only **************************** */

static void __exit savage_done(void)
{
        DBG("savage_done");
        pci_unregister_driver(&savagefb_driver);
}


/* ************************* init in-kernel code ************************** */

static int __init savagefb_setup(char *options)
{
#ifndef MODULE
        char *this_opt;

        if (!options || !*options)
                return 0;

        while ((this_opt = strsep(&options, ",")) != NULL) {
                mode_option = this_opt;
        }
#endif /* !MODULE */
        return 0;
}

static int __init savagefb_init(void)
{
        char *option;

        DBG("savagefb_init");

        if (fb_get_options("savagefb", &option))
                return -ENODEV;

        savagefb_setup(option);
        return pci_register_driver(&savagefb_driver);

}

module_init(savagefb_init);
module_exit(savage_done);

module_param(mode_option, charp, 0);
MODULE_PARM_DESC(mode_option, "Specify initial video mode");