/*
 * Copyright 2005-2006 Erik Waling
 * Copyright 2006 Stephane Marchesin
 * Copyright 2007-2009 Stuart Bennett
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <subdev/bios.h>

#include <drm/drmP.h>

#include "nouveau_drm.h"
#include "nouveau_reg.h"
#include "dispnv04/hw.h"
#include "nouveau_encoder.h"

#include <linux/io-mapping.h>
#include <linux/firmware.h>

/* these defines are made up */
#define NV_CIO_CRE_44_HEADA 0x0
#define NV_CIO_CRE_44_HEADB 0x3
#define FEATURE_MOBILE 0x10     /* also FEATURE_QUADRO for BMP */

#define EDID1_LEN 128

#define BIOSLOG(sip, fmt, arg...) NV_DEBUG(sip->dev, fmt, ##arg)
#define LOG_OLD_VALUE(x)

struct init_exec {
        bool execute;
        bool repeat;
};

static bool nv_cksum(const uint8_t *data, unsigned int length)
{
        /*
         * There's a few checksums in the BIOS, so here's a generic checking
         * function.
         */
        int i;
        uint8_t sum = 0;

        for (i = 0; i < length; i++)
                sum += data[i];

        if (sum)
                return true;

        return false;
}

static uint16_t clkcmptable(struct nvbios *bios, uint16_t clktable, int pxclk)
{
        int compare_record_len, i = 0;
        uint16_t compareclk, scriptptr = 0;

        if (bios->major_version < 5) /* pre BIT */
                compare_record_len = 3;
        else
                compare_record_len = 4;

        do {
                compareclk = ROM16(bios->data[clktable + compare_record_len * i]);
                if (pxclk >= compareclk * 10) {
                        if (bios->major_version < 5) {
                                uint8_t tmdssub = bios->data[clktable + 2 + compare_record_len * i];
                                scriptptr = ROM16(bios->data[bios->init_script_tbls_ptr + tmdssub * 2]);
                        } else
                                scriptptr = ROM16(bios->data[clktable + 2 + compare_record_len * i]);
                        break;
                }
                i++;
        } while (compareclk);

        return scriptptr;
}

static void
run_digital_op_script(struct drm_device *dev, uint16_t scriptptr,
                      struct dcb_output *dcbent, int head, bool dl)
{
        struct nouveau_drm *drm = nouveau_drm(dev);

        NV_INFO(drm, "0x%04X: Parsing digital output script table\n",
                 scriptptr);
        NVWriteVgaCrtc(dev, 0, NV_CIO_CRE_44, head ? NV_CIO_CRE_44_HEADB :
                                                 NV_CIO_CRE_44_HEADA);
        nouveau_bios_run_init_table(dev, scriptptr, dcbent, head);

        nv04_dfp_bind_head(dev, dcbent, head, dl);
}

static int call_lvds_manufacturer_script(struct drm_device *dev, struct dcb_output *dcbent, int head, enum LVDS_script script)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        uint8_t sub = bios->data[bios->fp.xlated_entry + script] + (bios->fp.link_c_increment && dcbent->or & DCB_OUTPUT_C ? 1 : 0);
        uint16_t scriptofs = ROM16(bios->data[bios->init_script_tbls_ptr + sub * 2]);

        if (!bios->fp.xlated_entry || !sub || !scriptofs)
                return -EINVAL;

        run_digital_op_script(dev, scriptofs, dcbent, head, bios->fp.dual_link);

        if (script == LVDS_PANEL_OFF) {
                /* off-on delay in ms */
                mdelay(ROM16(bios->data[bios->fp.xlated_entry + 7]));
        }
#ifdef __powerpc__
        /* Powerbook specific quirks */
        if (script == LVDS_RESET &&
            (dev->pci_device == 0x0179 || dev->pci_device == 0x0189 ||
             dev->pci_device == 0x0329))
                nv_write_tmds(dev, dcbent->or, 0, 0x02, 0x72);
#endif

        return 0;
}

static int run_lvds_table(struct drm_device *dev, struct dcb_output *dcbent, int head, enum LVDS_script script, int pxclk)
{
        /*
         * The BIT LVDS table's header has the information to setup the
         * necessary registers. Following the standard 4 byte header are:
         * A bitmask byte and a dual-link transition pxclk value for use in
         * selecting the init script when not using straps; 4 script pointers
         * for panel power, selected by output and on/off; and 8 table pointers
         * for panel init, the needed one determined by output, and bits in the
         * conf byte. These tables are similar to the TMDS tables, consisting
         * of a list of pxclks and script pointers.
         */
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        unsigned int outputset = (dcbent->or == 4) ? 1 : 0;
        uint16_t scriptptr = 0, clktable;

        /*
         * For now we assume version 3.0 table - g80 support will need some
         * changes
         */

        switch (script) {
        case LVDS_INIT:
                return -ENOSYS;
        case LVDS_BACKLIGHT_ON:
        case LVDS_PANEL_ON:
                scriptptr = ROM16(bios->data[bios->fp.lvdsmanufacturerpointer + 7 + outputset * 2]);
                break;
        case LVDS_BACKLIGHT_OFF:
        case LVDS_PANEL_OFF:
                scriptptr = ROM16(bios->data[bios->fp.lvdsmanufacturerpointer + 11 + outputset * 2]);
                break;
        case LVDS_RESET:
                clktable = bios->fp.lvdsmanufacturerpointer + 15;
                if (dcbent->or == 4)
                        clktable += 8;

                if (dcbent->lvdsconf.use_straps_for_mode) {
                        if (bios->fp.dual_link)
                                clktable += 4;
                        if (bios->fp.if_is_24bit)
                                clktable += 2;
                } else {
                        /* using EDID */
                        int cmpval_24bit = (dcbent->or == 4) ? 4 : 1;

                        if (bios->fp.dual_link) {
                                clktable += 4;
                                cmpval_24bit <<= 1;
                        }

                        if (bios->fp.strapless_is_24bit & cmpval_24bit)
                                clktable += 2;
                }

                clktable = ROM16(bios->data[clktable]);
                if (!clktable) {
                        NV_ERROR(drm, "Pixel clock comparison table not found\n");
                        return -ENOENT;
                }
                scriptptr = clkcmptable(bios, clktable, pxclk);
        }

        if (!scriptptr) {
                NV_ERROR(drm, "LVDS output init script not found\n");
                return -ENOENT;
        }
        run_digital_op_script(dev, scriptptr, dcbent, head, bios->fp.dual_link);

        return 0;
}

int call_lvds_script(struct drm_device *dev, struct dcb_output *dcbent, int head, enum LVDS_script script, int pxclk)
{
        /*
         * LVDS operations are multiplexed in an effort to present a single API
         * which works with two vastly differing underlying structures.
         * This acts as the demux
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_device *device = nv_device(drm->device);
        struct nvbios *bios = &drm->vbios;
        uint8_t lvds_ver = bios->data[bios->fp.lvdsmanufacturerpointer];
        uint32_t sel_clk_binding, sel_clk;
        int ret;

        if (bios->fp.last_script_invoc == (script << 1 | head) || !lvds_ver ||
            (lvds_ver >= 0x30 && script == LVDS_INIT))
                return 0;

        if (!bios->fp.lvds_init_run) {
                bios->fp.lvds_init_run = true;
                call_lvds_script(dev, dcbent, head, LVDS_INIT, pxclk);
        }

        if (script == LVDS_PANEL_ON && bios->fp.reset_after_pclk_change)
                call_lvds_script(dev, dcbent, head, LVDS_RESET, pxclk);
        if (script == LVDS_RESET && bios->fp.power_off_for_reset)
                call_lvds_script(dev, dcbent, head, LVDS_PANEL_OFF, pxclk);

        NV_INFO(drm, "Calling LVDS script %d:\n", script);

        /* don't let script change pll->head binding */
        sel_clk_binding = nv_rd32(device, NV_PRAMDAC_SEL_CLK) & 0x50000;

        if (lvds_ver < 0x30)
                ret = call_lvds_manufacturer_script(dev, dcbent, head, script);
        else
                ret = run_lvds_table(dev, dcbent, head, script, pxclk);

        bios->fp.last_script_invoc = (script << 1 | head);

        sel_clk = NVReadRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK) & ~0x50000;
        NVWriteRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK, sel_clk | sel_clk_binding);
        /* some scripts set a value in NV_PBUS_POWERCTRL_2 and break video overlay */
        nv_wr32(device, NV_PBUS_POWERCTRL_2, 0);

        return ret;
}

struct lvdstableheader {
        uint8_t lvds_ver, headerlen, recordlen;
};

static int parse_lvds_manufacturer_table_header(struct drm_device *dev, struct nvbios *bios, struct lvdstableheader *lth)
{
        /*
         * BMP version (0xa) LVDS table has a simple header of version and
         * record length. The BIT LVDS table has the typical BIT table header:
         * version byte, header length byte, record length byte, and a byte for
         * the maximum number of records that can be held in the table.
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        uint8_t lvds_ver, headerlen, recordlen;

        memset(lth, 0, sizeof(struct lvdstableheader));

        if (bios->fp.lvdsmanufacturerpointer == 0x0) {
                NV_ERROR(drm, "Pointer to LVDS manufacturer table invalid\n");
                return -EINVAL;
        }

        lvds_ver = bios->data[bios->fp.lvdsmanufacturerpointer];

        switch (lvds_ver) {
        case 0x0a:      /* pre NV40 */
                headerlen = 2;
                recordlen = bios->data[bios->fp.lvdsmanufacturerpointer + 1];
                break;
        case 0x30:      /* NV4x */
                headerlen = bios->data[bios->fp.lvdsmanufacturerpointer + 1];
                if (headerlen < 0x1f) {
                        NV_ERROR(drm, "LVDS table header not understood\n");
                        return -EINVAL;
                }
                recordlen = bios->data[bios->fp.lvdsmanufacturerpointer + 2];
                break;
        case 0x40:      /* G80/G90 */
                headerlen = bios->data[bios->fp.lvdsmanufacturerpointer + 1];
                if (headerlen < 0x7) {
                        NV_ERROR(drm, "LVDS table header not understood\n");
                        return -EINVAL;
                }
                recordlen = bios->data[bios->fp.lvdsmanufacturerpointer + 2];
                break;
        default:
                NV_ERROR(drm,
                         "LVDS table revision %d.%d not currently supported\n",
                         lvds_ver >> 4, lvds_ver & 0xf);
                return -ENOSYS;
        }

        lth->lvds_ver = lvds_ver;
        lth->headerlen = headerlen;
        lth->recordlen = recordlen;

        return 0;
}

static int
get_fp_strap(struct drm_device *dev, struct nvbios *bios)
{
        struct nouveau_device *device = nouveau_dev(dev);

        /*
         * The fp strap is normally dictated by the "User Strap" in
         * PEXTDEV_BOOT_0[20:16], but on BMP cards when bit 2 of the
         * Internal_Flags struct at 0x48 is set, the user strap gets overriden
         * by the PCI subsystem ID during POST, but not before the previous user
         * strap has been committed to CR58 for CR57=0xf on head A, which may be
         * read and used instead
         */

        if (bios->major_version < 5 && bios->data[0x48] & 0x4)
                return NVReadVgaCrtc5758(dev, 0, 0xf) & 0xf;

        if (device->card_type >= NV_50)
                return (nv_rd32(device, NV_PEXTDEV_BOOT_0) >> 24) & 0xf;
        else
                return (nv_rd32(device, NV_PEXTDEV_BOOT_0) >> 16) & 0xf;
}

static int parse_fp_mode_table(struct drm_device *dev, struct nvbios *bios)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        uint8_t *fptable;
        uint8_t fptable_ver, headerlen = 0, recordlen, fpentries = 0xf, fpindex;
        int ret, ofs, fpstrapping;
        struct lvdstableheader lth;

        if (bios->fp.fptablepointer == 0x0) {
                /* Apple cards don't have the fp table; the laptops use DDC */
                /* The table is also missing on some x86 IGPs */
#ifndef __powerpc__
                NV_ERROR(drm, "Pointer to flat panel table invalid\n");
#endif
                bios->digital_min_front_porch = 0x4b;
                return 0;
        }

        fptable = &bios->data[bios->fp.fptablepointer];
        fptable_ver = fptable[0];

        switch (fptable_ver) {
        /*
         * BMP version 0x5.0x11 BIOSen have version 1 like tables, but no
         * version field, and miss one of the spread spectrum/PWM bytes.
         * This could affect early GF2Go parts (not seen any appropriate ROMs
         * though). Here we assume that a version of 0x05 matches this case
         * (combining with a BMP version check would be better), as the
         * common case for the panel type field is 0x0005, and that is in
         * fact what we are reading the first byte of.
         */
        case 0x05:      /* some NV10, 11, 15, 16 */
                recordlen = 42;
                ofs = -1;
                break;
        case 0x10:      /* some NV15/16, and NV11+ */
                recordlen = 44;
                ofs = 0;
                break;
        case 0x20:      /* NV40+ */
                headerlen = fptable[1];
                recordlen = fptable[2];
                fpentries = fptable[3];
                /*
                 * fptable[4] is the minimum
                 * RAMDAC_FP_HCRTC -> RAMDAC_FP_HSYNC_START gap
                 */
                bios->digital_min_front_porch = fptable[4];
                ofs = -7;
                break;
        default:
                NV_ERROR(drm,
                         "FP table revision %d.%d not currently supported\n",
                         fptable_ver >> 4, fptable_ver & 0xf);
                return -ENOSYS;
        }

        if (!bios->is_mobile) /* !mobile only needs digital_min_front_porch */
                return 0;

        ret = parse_lvds_manufacturer_table_header(dev, bios, &lth);
        if (ret)
                return ret;

        if (lth.lvds_ver == 0x30 || lth.lvds_ver == 0x40) {
                bios->fp.fpxlatetableptr = bios->fp.lvdsmanufacturerpointer +
                                                        lth.headerlen + 1;
                bios->fp.xlatwidth = lth.recordlen;
        }
        if (bios->fp.fpxlatetableptr == 0x0) {
                NV_ERROR(drm, "Pointer to flat panel xlat table invalid\n");
                return -EINVAL;
        }

        fpstrapping = get_fp_strap(dev, bios);

        fpindex = bios->data[bios->fp.fpxlatetableptr +
                                        fpstrapping * bios->fp.xlatwidth];

        if (fpindex > fpentries) {
                NV_ERROR(drm, "Bad flat panel table index\n");
                return -ENOENT;
        }

        /* nv4x cards need both a strap value and fpindex of 0xf to use DDC */
        if (lth.lvds_ver > 0x10)
                bios->fp_no_ddc = fpstrapping != 0xf || fpindex != 0xf;

        /*
         * If either the strap or xlated fpindex value are 0xf there is no
         * panel using a strap-derived bios mode present.  this condition
         * includes, but is different from, the DDC panel indicator above
         */
        if (fpstrapping == 0xf || fpindex == 0xf)
                return 0;

        bios->fp.mode_ptr = bios->fp.fptablepointer + headerlen +
                            recordlen * fpindex + ofs;

        NV_INFO(drm, "BIOS FP mode: %dx%d (%dkHz pixel clock)\n",
                 ROM16(bios->data[bios->fp.mode_ptr + 11]) + 1,
                 ROM16(bios->data[bios->fp.mode_ptr + 25]) + 1,
                 ROM16(bios->data[bios->fp.mode_ptr + 7]) * 10);

        return 0;
}

bool nouveau_bios_fp_mode(struct drm_device *dev, struct drm_display_mode *mode)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        uint8_t *mode_entry = &bios->data[bios->fp.mode_ptr];

        if (!mode)      /* just checking whether we can produce a mode */
                return bios->fp.mode_ptr;

        memset(mode, 0, sizeof(struct drm_display_mode));
        /*
         * For version 1.0 (version in byte 0):
         * bytes 1-2 are "panel type", including bits on whether Colour/mono,
         * single/dual link, and type (TFT etc.)
         * bytes 3-6 are bits per colour in RGBX
         */
        mode->clock = ROM16(mode_entry[7]) * 10;
        /* bytes 9-10 is HActive */
        mode->hdisplay = ROM16(mode_entry[11]) + 1;
        /*
         * bytes 13-14 is HValid Start
         * bytes 15-16 is HValid End
         */
        mode->hsync_start = ROM16(mode_entry[17]) + 1;
        mode->hsync_end = ROM16(mode_entry[19]) + 1;
        mode->htotal = ROM16(mode_entry[21]) + 1;
        /* bytes 23-24, 27-30 similarly, but vertical */
        mode->vdisplay = ROM16(mode_entry[25]) + 1;
        mode->vsync_start = ROM16(mode_entry[31]) + 1;
        mode->vsync_end = ROM16(mode_entry[33]) + 1;
        mode->vtotal = ROM16(mode_entry[35]) + 1;
        mode->flags |= (mode_entry[37] & 0x10) ?
                        DRM_MODE_FLAG_PHSYNC : DRM_MODE_FLAG_NHSYNC;
        mode->flags |= (mode_entry[37] & 0x1) ?
                        DRM_MODE_FLAG_PVSYNC : DRM_MODE_FLAG_NVSYNC;
        /*
         * bytes 38-39 relate to spread spectrum settings
         * bytes 40-43 are something to do with PWM
         */

        mode->status = MODE_OK;
        mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
        drm_mode_set_name(mode);
        return bios->fp.mode_ptr;
}

int nouveau_bios_parse_lvds_table(struct drm_device *dev, int pxclk, bool *dl, bool *if_is_24bit)
{
        /*
         * The LVDS table header is (mostly) described in
         * parse_lvds_manufacturer_table_header(): the BIT header additionally
         * contains the dual-link transition pxclk (in 10s kHz), at byte 5 - if
         * straps are not being used for the panel, this specifies the frequency
         * at which modes should be set up in the dual link style.
         *
         * Following the header, the BMP (ver 0xa) table has several records,
         * indexed by a separate xlat table, indexed in turn by the fp strap in
         * EXTDEV_BOOT. Each record had a config byte, followed by 6 script
         * numbers for use by INIT_SUB which controlled panel init and power,
         * and finally a dword of ms to sleep between power off and on
         * operations.
         *
         * In the BIT versions, the table following the header serves as an
         * integrated config and xlat table: the records in the table are
         * indexed by the FP strap nibble in EXTDEV_BOOT, and each record has
         * two bytes - the first as a config byte, the second for indexing the
         * fp mode table pointed to by the BIT 'D' table
         *
         * DDC is not used until after card init, so selecting the correct table
         * entry and setting the dual link flag for EDID equipped panels,
         * requiring tests against the native-mode pixel clock, cannot be done
         * until later, when this function should be called with non-zero pxclk
         */
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        int fpstrapping = get_fp_strap(dev, bios), lvdsmanufacturerindex = 0;
        struct lvdstableheader lth;
        uint16_t lvdsofs;
        int ret, chip_version = bios->chip_version;

        ret = parse_lvds_manufacturer_table_header(dev, bios, &lth);
        if (ret)
                return ret;

        switch (lth.lvds_ver) {
        case 0x0a:      /* pre NV40 */
                lvdsmanufacturerindex = bios->data[
                                        bios->fp.fpxlatemanufacturertableptr +
                                        fpstrapping];

                /* we're done if this isn't the EDID panel case */
                if (!pxclk)
                        break;

                if (chip_version < 0x25) {
                        /* nv17 behaviour
                         *
                         * It seems the old style lvds script pointer is reused
                         * to select 18/24 bit colour depth for EDID panels.
                         */
                        lvdsmanufacturerindex =
                                (bios->legacy.lvds_single_a_script_ptr & 1) ?
                                                                        2 : 0;
                        if (pxclk >= bios->fp.duallink_transition_clk)
                                lvdsmanufacturerindex++;
                } else if (chip_version < 0x30) {
                        /* nv28 behaviour (off-chip encoder)
                         *
                         * nv28 does a complex dance of first using byte 121 of
                         * the EDID to choose the lvdsmanufacturerindex, then
                         * later attempting to match the EDID manufacturer and
                         * product IDs in a table (signature 'pidt' (panel id
                         * table?)), setting an lvdsmanufacturerindex of 0 and
                         * an fp strap of the match index (or 0xf if none)
                         */
                        lvdsmanufacturerindex = 0;
                } else {
                        /* nv31, nv34 behaviour */
                        lvdsmanufacturerindex = 0;
                        if (pxclk >= bios->fp.duallink_transition_clk)
                                lvdsmanufacturerindex = 2;
                        if (pxclk >= 140000)
                                lvdsmanufacturerindex = 3;
                }

                /*
                 * nvidia set the high nibble of (cr57=f, cr58) to
                 * lvdsmanufacturerindex in this case; we don't
                 */
                break;
        case 0x30:      /* NV4x */
        case 0x40:      /* G80/G90 */
                lvdsmanufacturerindex = fpstrapping;
                break;
        default:
                NV_ERROR(drm, "LVDS table revision not currently supported\n");
                return -ENOSYS;
        }

        lvdsofs = bios->fp.xlated_entry = bios->fp.lvdsmanufacturerpointer + lth.headerlen + lth.recordlen * lvdsmanufacturerindex;
        switch (lth.lvds_ver) {
        case 0x0a:
                bios->fp.power_off_for_reset = bios->data[lvdsofs] & 1;
                bios->fp.reset_after_pclk_change = bios->data[lvdsofs] & 2;
                bios->fp.dual_link = bios->data[lvdsofs] & 4;
                bios->fp.link_c_increment = bios->data[lvdsofs] & 8;
                *if_is_24bit = bios->data[lvdsofs] & 16;
                break;
        case 0x30:
        case 0x40:
                /*
                 * No sign of the "power off for reset" or "reset for panel
                 * on" bits, but it's safer to assume we should
                 */
                bios->fp.power_off_for_reset = true;
                bios->fp.reset_after_pclk_change = true;

                /*
                 * It's ok lvdsofs is wrong for nv4x edid case; dual_link is
                 * over-written, and if_is_24bit isn't used
                 */
                bios->fp.dual_link = bios->data[lvdsofs] & 1;
                bios->fp.if_is_24bit = bios->data[lvdsofs] & 2;
                bios->fp.strapless_is_24bit = bios->data[bios->fp.lvdsmanufacturerpointer + 4];
                bios->fp.duallink_transition_clk = ROM16(bios->data[bios->fp.lvdsmanufacturerpointer + 5]) * 10;
                break;
        }

        /* set dual_link flag for EDID case */
        if (pxclk && (chip_version < 0x25 || chip_version > 0x28))
                bios->fp.dual_link = (pxclk >= bios->fp.duallink_transition_clk);

        *dl = bios->fp.dual_link;

        return 0;
}

int run_tmds_table(struct drm_device *dev, struct dcb_output *dcbent, int head, int pxclk)
{
        /*
         * the pxclk parameter is in kHz
         *
         * This runs the TMDS regs setting code found on BIT bios cards
         *
         * For ffs(or) == 1 use the first table, for ffs(or) == 2 and
         * ffs(or) == 3, use the second.
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_device *device = nv_device(drm->device);
        struct nvbios *bios = &drm->vbios;
        int cv = bios->chip_version;
        uint16_t clktable = 0, scriptptr;
        uint32_t sel_clk_binding, sel_clk;

        /* pre-nv17 off-chip tmds uses scripts, post nv17 doesn't */
        if (cv >= 0x17 && cv != 0x1a && cv != 0x20 &&
            dcbent->location != DCB_LOC_ON_CHIP)
                return 0;

        switch (ffs(dcbent->or)) {
        case 1:
                clktable = bios->tmds.output0_script_ptr;
                break;
        case 2:
        case 3:
                clktable = bios->tmds.output1_script_ptr;
                break;
        }

        if (!clktable) {
                NV_ERROR(drm, "Pixel clock comparison table not found\n");
                return -EINVAL;
        }

        scriptptr = clkcmptable(bios, clktable, pxclk);

        if (!scriptptr) {
                NV_ERROR(drm, "TMDS output init script not found\n");
                return -ENOENT;
        }

        /* don't let script change pll->head binding */
        sel_clk_binding = nv_rd32(device, NV_PRAMDAC_SEL_CLK) & 0x50000;
        run_digital_op_script(dev, scriptptr, dcbent, head, pxclk >= 165000);
        sel_clk = NVReadRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK) & ~0x50000;
        NVWriteRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK, sel_clk | sel_clk_binding);

        return 0;
}

static void parse_script_table_pointers(struct nvbios *bios, uint16_t offset)
{
        /*
         * Parses the init table segment for pointers used in script execution.
         *
         * offset + 0  (16 bits): init script tables pointer
         * offset + 2  (16 bits): macro index table pointer
         * offset + 4  (16 bits): macro table pointer
         * offset + 6  (16 bits): condition table pointer
         * offset + 8  (16 bits): io condition table pointer
         * offset + 10 (16 bits): io flag condition table pointer
         * offset + 12 (16 bits): init function table pointer
         */

        bios->init_script_tbls_ptr = ROM16(bios->data[offset]);
}

static int parse_bit_A_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * Parses the load detect values for g80 cards.
         *
         * offset + 0 (16 bits): loadval table pointer
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        uint16_t load_table_ptr;
        uint8_t version, headerlen, entrylen, num_entries;

        if (bitentry->length != 3) {
                NV_ERROR(drm, "Do not understand BIT A table\n");
                return -EINVAL;
        }

        load_table_ptr = ROM16(bios->data[bitentry->offset]);

        if (load_table_ptr == 0x0) {
                NV_DEBUG(drm, "Pointer to BIT loadval table invalid\n");
                return -EINVAL;
        }

        version = bios->data[load_table_ptr];

        if (version != 0x10) {
                NV_ERROR(drm, "BIT loadval table version %d.%d not supported\n",
                         version >> 4, version & 0xF);
                return -ENOSYS;
        }

        headerlen = bios->data[load_table_ptr + 1];
        entrylen = bios->data[load_table_ptr + 2];
        num_entries = bios->data[load_table_ptr + 3];

        if (headerlen != 4 || entrylen != 4 || num_entries != 2) {
                NV_ERROR(drm, "Do not understand BIT loadval table\n");
                return -EINVAL;
        }

        /* First entry is normal dac, 2nd tv-out perhaps? */
        bios->dactestval = ROM32(bios->data[load_table_ptr + headerlen]) & 0x3ff;

        return 0;
}

static int parse_bit_display_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * Parses the flat panel table segment that the bit entry points to.
         * Starting at bitentry->offset:
         *
         * offset + 0  (16 bits): ??? table pointer - seems to have 18 byte
         * records beginning with a freq.
         * offset + 2  (16 bits): mode table pointer
         */
        struct nouveau_drm *drm = nouveau_drm(dev);

        if (bitentry->length != 4) {
                NV_ERROR(drm, "Do not understand BIT display table\n");
                return -EINVAL;
        }

        bios->fp.fptablepointer = ROM16(bios->data[bitentry->offset + 2]);

        return 0;
}

static int parse_bit_init_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * Parses the init table segment that the bit entry points to.
         *
         * See parse_script_table_pointers for layout
         */
        struct nouveau_drm *drm = nouveau_drm(dev);

        if (bitentry->length < 14) {
                NV_ERROR(drm, "Do not understand init table\n");
                return -EINVAL;
        }

        parse_script_table_pointers(bios, bitentry->offset);
        return 0;
}

static int parse_bit_i_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * BIT 'i' (info?) table
         *
         * offset + 0  (32 bits): BIOS version dword (as in B table)
         * offset + 5  (8  bits): BIOS feature byte (same as for BMP?)
         * offset + 13 (16 bits): pointer to table containing DAC load
         * detection comparison values
         *
         * There's other things in the table, purpose unknown
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        uint16_t daccmpoffset;
        uint8_t dacver, dacheaderlen;

        if (bitentry->length < 6) {
                NV_ERROR(drm, "BIT i table too short for needed information\n");
                return -EINVAL;
        }

        /*
         * bit 4 seems to indicate a mobile bios (doesn't suffer from BMP's
         * Quadro identity crisis), other bits possibly as for BMP feature byte
         */
        bios->feature_byte = bios->data[bitentry->offset + 5];
        bios->is_mobile = bios->feature_byte & FEATURE_MOBILE;

        if (bitentry->length < 15) {
                NV_WARN(drm, "BIT i table not long enough for DAC load "
                               "detection comparison table\n");
                return -EINVAL;
        }

        daccmpoffset = ROM16(bios->data[bitentry->offset + 13]);

        /* doesn't exist on g80 */
        if (!daccmpoffset)
                return 0;

        /*
         * The first value in the table, following the header, is the
         * comparison value, the second entry is a comparison value for
         * TV load detection.
         */

        dacver = bios->data[daccmpoffset];
        dacheaderlen = bios->data[daccmpoffset + 1];

        if (dacver != 0x00 && dacver != 0x10) {
                NV_WARN(drm, "DAC load detection comparison table version "
                               "%d.%d not known\n", dacver >> 4, dacver & 0xf);
                return -ENOSYS;
        }

        bios->dactestval = ROM32(bios->data[daccmpoffset + dacheaderlen]);
        bios->tvdactestval = ROM32(bios->data[daccmpoffset + dacheaderlen + 4]);

        return 0;
}

static int parse_bit_lvds_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * Parses the LVDS table segment that the bit entry points to.
         * Starting at bitentry->offset:
         *
         * offset + 0  (16 bits): LVDS strap xlate table pointer
         */

        struct nouveau_drm *drm = nouveau_drm(dev);

        if (bitentry->length != 2) {
                NV_ERROR(drm, "Do not understand BIT LVDS table\n");
                return -EINVAL;
        }

        /*
         * No idea if it's still called the LVDS manufacturer table, but
         * the concept's close enough.
         */
        bios->fp.lvdsmanufacturerpointer = ROM16(bios->data[bitentry->offset]);

        return 0;
}

static int
parse_bit_M_tbl_entry(struct drm_device *dev, struct nvbios *bios,
                      struct bit_entry *bitentry)
{
        /*
         * offset + 2  (8  bits): number of options in an
         *      INIT_RAM_RESTRICT_ZM_REG_GROUP opcode option set
         * offset + 3  (16 bits): pointer to strap xlate table for RAM
         *      restrict option selection
         *
         * There's a bunch of bits in this table other than the RAM restrict
         * stuff that we don't use - their use currently unknown
         */

        /*
         * Older bios versions don't have a sufficiently long table for
         * what we want
         */
        if (bitentry->length < 0x5)
                return 0;

        if (bitentry->version < 2) {
                bios->ram_restrict_group_count = bios->data[bitentry->offset + 2];
                bios->ram_restrict_tbl_ptr = ROM16(bios->data[bitentry->offset + 3]);
        } else {
                bios->ram_restrict_group_count = bios->data[bitentry->offset + 0];
                bios->ram_restrict_tbl_ptr = ROM16(bios->data[bitentry->offset + 1]);
        }

        return 0;
}

static int parse_bit_tmds_tbl_entry(struct drm_device *dev, struct nvbios *bios, struct bit_entry *bitentry)
{
        /*
         * Parses the pointer to the TMDS table
         *
         * Starting at bitentry->offset:
         *
         * offset + 0  (16 bits): TMDS table pointer
         *
         * The TMDS table is typically found just before the DCB table, with a
         * characteristic signature of 0x11,0x13 (1.1 being version, 0x13 being
         * length?)
         *
         * At offset +7 is a pointer to a script, which I don't know how to
         * run yet.
         * At offset +9 is a pointer to another script, likewise
         * Offset +11 has a pointer to a table where the first word is a pxclk
         * frequency and the second word a pointer to a script, which should be
         * run if the comparison pxclk frequency is less than the pxclk desired.
         * This repeats for decreasing comparison frequencies
         * Offset +13 has a pointer to a similar table
         * The selection of table (and possibly +7/+9 script) is dictated by
         * "or" from the DCB.
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        uint16_t tmdstableptr, script1, script2;

        if (bitentry->length != 2) {
                NV_ERROR(drm, "Do not understand BIT TMDS table\n");
                return -EINVAL;
        }

        tmdstableptr = ROM16(bios->data[bitentry->offset]);
        if (!tmdstableptr) {
                NV_ERROR(drm, "Pointer to TMDS table invalid\n");
                return -EINVAL;
        }

        NV_INFO(drm, "TMDS table version %d.%d\n",
                bios->data[tmdstableptr] >> 4, bios->data[tmdstableptr] & 0xf);

        /* nv50+ has v2.0, but we don't parse it atm */
        if (bios->data[tmdstableptr] != 0x11)
                return -ENOSYS;

        /*
         * These two scripts are odd: they don't seem to get run even when
         * they are not stubbed.
         */
        script1 = ROM16(bios->data[tmdstableptr + 7]);
        script2 = ROM16(bios->data[tmdstableptr + 9]);
        if (bios->data[script1] != 'q' || bios->data[script2] != 'q')
                NV_WARN(drm, "TMDS table script pointers not stubbed\n");

        bios->tmds.output0_script_ptr = ROM16(bios->data[tmdstableptr + 11]);
        bios->tmds.output1_script_ptr = ROM16(bios->data[tmdstableptr + 13]);

        return 0;
}

struct bit_table {
        const char id;
        int (* const parse_fn)(struct drm_device *, struct nvbios *, struct bit_entry *);
};

#define BIT_TABLE(id, funcid) ((struct bit_table){ id, parse_bit_##funcid##_tbl_entry })

int
bit_table(struct drm_device *dev, u8 id, struct bit_entry *bit)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        u8 entries, *entry;

        if (bios->type != NVBIOS_BIT)
                return -ENODEV;

        entries = bios->data[bios->offset + 10];
        entry   = &bios->data[bios->offset + 12];
        while (entries--) {
                if (entry[0] == id) {
                        bit->id = entry[0];
                        bit->version = entry[1];
                        bit->length = ROM16(entry[2]);
                        bit->offset = ROM16(entry[4]);
                        bit->data = ROMPTR(dev, entry[4]);
                        return 0;
                }

                entry += bios->data[bios->offset + 9];
        }

        return -ENOENT;
}

static int

parse_bit_table(struct nvbios *bios, const uint16_t bitoffset,
                struct bit_table *table)
{
        struct drm_device *dev = bios->dev;
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct bit_entry bitentry;

        if (bit_table(dev, table->id, &bitentry) == 0)
                return table->parse_fn(dev, bios, &bitentry);

        NV_INFO(drm, "BIT table '%c' not found\n", table->id);
        return -ENOSYS;
}

static int
parse_bit_structure(struct nvbios *bios, const uint16_t bitoffset)
{
        int ret;

        /*
         * The only restriction on parsing order currently is having 'i' first
         * for use of bios->*_version or bios->feature_byte while parsing;
         * functions shouldn't be actually *doing* anything apart from pulling
         * data from the image into the bios struct, thus no interdependencies
         */
        ret = parse_bit_table(bios, bitoffset, &BIT_TABLE('i', i));
        if (ret) /* info? */
                return ret;
        if (bios->major_version >= 0x60) /* g80+ */
                parse_bit_table(bios, bitoffset, &BIT_TABLE('A', A));
        parse_bit_table(bios, bitoffset, &BIT_TABLE('D', display));
        ret = parse_bit_table(bios, bitoffset, &BIT_TABLE('I', init));
        if (ret)
                return ret;
        parse_bit_table(bios, bitoffset, &BIT_TABLE('M', M)); /* memory? */
        parse_bit_table(bios, bitoffset, &BIT_TABLE('L', lvds));
        parse_bit_table(bios, bitoffset, &BIT_TABLE('T', tmds));

        return 0;
}

static int parse_bmp_structure(struct drm_device *dev, struct nvbios *bios, unsigned int offset)
{
        /*
         * Parses the BMP structure for useful things, but does not act on them
         *
         * offset +   5: BMP major version
         * offset +   6: BMP minor version
         * offset +   9: BMP feature byte
         * offset +  10: BCD encoded BIOS version
         *
         * offset +  18: init script table pointer (for bios versions < 5.10h)
         * offset +  20: extra init script table pointer (for bios
         * versions < 5.10h)
         *
         * offset +  24: memory init table pointer (used on early bios versions)
         * offset +  26: SDR memory sequencing setup data table
         * offset +  28: DDR memory sequencing setup data table
         *
         * offset +  54: index of I2C CRTC pair to use for CRT output
         * offset +  55: index of I2C CRTC pair to use for TV output
         * offset +  56: index of I2C CRTC pair to use for flat panel output
         * offset +  58: write CRTC index for I2C pair 0
         * offset +  59: read CRTC index for I2C pair 0
         * offset +  60: write CRTC index for I2C pair 1
         * offset +  61: read CRTC index for I2C pair 1
         *
         * offset +  67: maximum internal PLL frequency (single stage PLL)
         * offset +  71: minimum internal PLL frequency (single stage PLL)
         *
         * offset +  75: script table pointers, as described in
         * parse_script_table_pointers
         *
         * offset +  89: TMDS single link output A table pointer
         * offset +  91: TMDS single link output B table pointer
         * offset +  95: LVDS single link output A table pointer
         * offset + 105: flat panel timings table pointer
         * offset + 107: flat panel strapping translation table pointer
         * offset + 117: LVDS manufacturer panel config table pointer
         * offset + 119: LVDS manufacturer strapping translation table pointer
         *
         * offset + 142: PLL limits table pointer
         *
         * offset + 156: minimum pixel clock for LVDS dual link
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        uint8_t *bmp = &bios->data[offset], bmp_version_major, bmp_version_minor;
        uint16_t bmplength;
        uint16_t legacy_scripts_offset, legacy_i2c_offset;

        /* load needed defaults in case we can't parse this info */
        bios->digital_min_front_porch = 0x4b;
        bios->fmaxvco = 256000;
        bios->fminvco = 128000;
        bios->fp.duallink_transition_clk = 90000;

        bmp_version_major = bmp[5];
        bmp_version_minor = bmp[6];

        NV_INFO(drm, "BMP version %d.%d\n",
                 bmp_version_major, bmp_version_minor);

        /*
         * Make sure that 0x36 is blank and can't be mistaken for a DCB
         * pointer on early versions
         */
        if (bmp_version_major < 5)
                *(uint16_t *)&bios->data[0x36] = 0;

        /*
         * Seems that the minor version was 1 for all major versions prior
         * to 5. Version 6 could theoretically exist, but I suspect BIT
         * happened instead.
         */
        if ((bmp_version_major < 5 && bmp_version_minor != 1) || bmp_version_major > 5) {
                NV_ERROR(drm, "You have an unsupported BMP version. "
                                "Please send in your bios\n");
                return -ENOSYS;
        }

        if (bmp_version_major == 0)
                /* nothing that's currently useful in this version */
                return 0;
        else if (bmp_version_major == 1)
                bmplength = 44; /* exact for 1.01 */
        else if (bmp_version_major == 2)
                bmplength = 48; /* exact for 2.01 */
        else if (bmp_version_major == 3)
                bmplength = 54;
                /* guessed - mem init tables added in this version */
        else if (bmp_version_major == 4 || bmp_version_minor < 0x1)
                /* don't know if 5.0 exists... */
                bmplength = 62;
                /* guessed - BMP I2C indices added in version 4*/
        else if (bmp_version_minor < 0x6)
                bmplength = 67; /* exact for 5.01 */
        else if (bmp_version_minor < 0x10)
                bmplength = 75; /* exact for 5.06 */
        else if (bmp_version_minor == 0x10)
                bmplength = 89; /* exact for 5.10h */
        else if (bmp_version_minor < 0x14)
                bmplength = 118; /* exact for 5.11h */
        else if (bmp_version_minor < 0x24)
                /*
                 * Not sure of version where pll limits came in;
                 * certainly exist by 0x24 though.
                 */
                /* length not exact: this is long enough to get lvds members */
                bmplength = 123;
        else if (bmp_version_minor < 0x27)
                /*
                 * Length not exact: this is long enough to get pll limit
                 * member
                 */
                bmplength = 144;
        else
                /*
                 * Length not exact: this is long enough to get dual link
                 * transition clock.
                 */
                bmplength = 158;

        /* checksum */
        if (nv_cksum(bmp, 8)) {
                NV_ERROR(drm, "Bad BMP checksum\n");
                return -EINVAL;
        }

        /*
         * Bit 4 seems to indicate either a mobile bios or a quadro card --
         * mobile behaviour consistent (nv11+), quadro only seen nv18gl-nv36gl
         * (not nv10gl), bit 5 that the flat panel tables are present, and
         * bit 6 a tv bios.
         */
        bios->feature_byte = bmp[9];

        if (bmp_version_major < 5 || bmp_version_minor < 0x10)
                bios->old_style_init = true;
        legacy_scripts_offset = 18;
        if (bmp_version_major < 2)
                legacy_scripts_offset -= 4;
        bios->init_script_tbls_ptr = ROM16(bmp[legacy_scripts_offset]);
        bios->extra_init_script_tbl_ptr = ROM16(bmp[legacy_scripts_offset + 2]);

        if (bmp_version_major > 2) {    /* appears in BMP 3 */
                bios->legacy.mem_init_tbl_ptr = ROM16(bmp[24]);
                bios->legacy.sdr_seq_tbl_ptr = ROM16(bmp[26]);
                bios->legacy.ddr_seq_tbl_ptr = ROM16(bmp[28]);
        }

        legacy_i2c_offset = 0x48;       /* BMP version 2 & 3 */
        if (bmplength > 61)
                legacy_i2c_offset = offset + 54;
        bios->legacy.i2c_indices.crt = bios->data[legacy_i2c_offset];
        bios->legacy.i2c_indices.tv = bios->data[legacy_i2c_offset + 1];
        bios->legacy.i2c_indices.panel = bios->data[legacy_i2c_offset + 2];

        if (bmplength > 74) {
                bios->fmaxvco = ROM32(bmp[67]);
                bios->fminvco = ROM32(bmp[71]);
        }
        if (bmplength > 88)
                parse_script_table_pointers(bios, offset + 75);
        if (bmplength > 94) {
                bios->tmds.output0_script_ptr = ROM16(bmp[89]);
                bios->tmds.output1_script_ptr = ROM16(bmp[91]);
                /*
                 * Never observed in use with lvds scripts, but is reused for
                 * 18/24 bit panel interface default for EDID equipped panels
                 * (if_is_24bit not set directly to avoid any oscillation).
                 */
                bios->legacy.lvds_single_a_script_ptr = ROM16(bmp[95]);
        }
        if (bmplength > 108) {
                bios->fp.fptablepointer = ROM16(bmp[105]);
                bios->fp.fpxlatetableptr = ROM16(bmp[107]);
                bios->fp.xlatwidth = 1;
        }
        if (bmplength > 120) {
                bios->fp.lvdsmanufacturerpointer = ROM16(bmp[117]);
                bios->fp.fpxlatemanufacturertableptr = ROM16(bmp[119]);
        }
#if 0
        if (bmplength > 143)
                bios->pll_limit_tbl_ptr = ROM16(bmp[142]);
#endif

        if (bmplength > 157)
                bios->fp.duallink_transition_clk = ROM16(bmp[156]) * 10;

        return 0;
}

static uint16_t findstr(uint8_t *data, int n, const uint8_t *str, int len)
{
        int i, j;

        for (i = 0; i <= (n - len); i++) {
                for (j = 0; j < len; j++)
                        if (data[i + j] != str[j])
                                break;
                if (j == len)
                        return i;
        }

        return 0;
}

void *
olddcb_table(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        u8 *dcb = NULL;

        if (nv_device(drm->device)->card_type > NV_04)
                dcb = ROMPTR(dev, drm->vbios.data[0x36]);
        if (!dcb) {
                NV_WARN(drm, "No DCB data found in VBIOS\n");
                return NULL;
        }

        if (dcb[0] >= 0x41) {
                NV_WARN(drm, "DCB version 0x%02x unknown\n", dcb[0]);
                return NULL;
        } else
        if (dcb[0] >= 0x30) {
                if (ROM32(dcb[6]) == 0x4edcbdcb)
                        return dcb;
        } else
        if (dcb[0] >= 0x20) {
                if (ROM32(dcb[4]) == 0x4edcbdcb)
                        return dcb;
        } else
        if (dcb[0] >= 0x15) {
                if (!memcmp(&dcb[-7], "DEV_REC", 7))
                        return dcb;
        } else {
                /*
                 * v1.4 (some NV15/16, NV11+) seems the same as v1.5, but
                 * always has the same single (crt) entry, even when tv-out
                 * present, so the conclusion is this version cannot really
                 * be used.
                 *
                 * v1.2 tables (some NV6/10, and NV15+) normally have the
                 * same 5 entries, which are not specific to the card and so
                 * no use.
                 *
                 * v1.2 does have an I2C table that read_dcb_i2c_table can
                 * handle, but cards exist (nv11 in #14821) with a bad i2c
                 * table pointer, so use the indices parsed in
                 * parse_bmp_structure.
                 *
                 * v1.1 (NV5+, maybe some NV4) is entirely unhelpful
                 */
                NV_WARN(drm, "No useful DCB data in VBIOS\n");
                return NULL;
        }

        NV_WARN(drm, "DCB header validation failed\n");
        return NULL;
}

void *
olddcb_outp(struct drm_device *dev, u8 idx)
{
        u8 *dcb = olddcb_table(dev);
        if (dcb && dcb[0] >= 0x30) {
                if (idx < dcb[2])
                        return dcb + dcb[1] + (idx * dcb[3]);
        } else
        if (dcb && dcb[0] >= 0x20) {
                u8 *i2c = ROMPTR(dev, dcb[2]);
                u8 *ent = dcb + 8 + (idx * 8);
                if (i2c && ent < i2c)
                        return ent;
        } else
        if (dcb && dcb[0] >= 0x15) {
                u8 *i2c = ROMPTR(dev, dcb[2]);
                u8 *ent = dcb + 4 + (idx * 10);
                if (i2c && ent < i2c)
                        return ent;
        }

        return NULL;
}

int
olddcb_outp_foreach(struct drm_device *dev, void *data,
                 int (*exec)(struct drm_device *, void *, int idx, u8 *outp))
{
        int ret, idx = -1;
        u8 *outp = NULL;
        while ((outp = olddcb_outp(dev, ++idx))) {
                if (ROM32(outp[0]) == 0x00000000)
                        break; /* seen on an NV11 with DCB v1.5 */
                if (ROM32(outp[0]) == 0xffffffff)
                        break; /* seen on an NV17 with DCB v2.0 */

                if ((outp[0] & 0x0f) == DCB_OUTPUT_UNUSED)
                        continue;
                if ((outp[0] & 0x0f) == DCB_OUTPUT_EOL)
                        break;

                ret = exec(dev, data, idx, outp);
                if (ret)
                        return ret;
        }

        return 0;
}

u8 *
olddcb_conntab(struct drm_device *dev)
{
        u8 *dcb = olddcb_table(dev);
        if (dcb && dcb[0] >= 0x30 && dcb[1] >= 0x16) {
                u8 *conntab = ROMPTR(dev, dcb[0x14]);
                if (conntab && conntab[0] >= 0x30 && conntab[0] <= 0x40)
                        return conntab;
        }
        return NULL;
}

u8 *
olddcb_conn(struct drm_device *dev, u8 idx)
{
        u8 *conntab = olddcb_conntab(dev);
        if (conntab && idx < conntab[2])
                return conntab + conntab[1] + (idx * conntab[3]);
        return NULL;
}

static struct dcb_output *new_dcb_entry(struct dcb_table *dcb)
{
        struct dcb_output *entry = &dcb->entry[dcb->entries];

        memset(entry, 0, sizeof(struct dcb_output));
        entry->index = dcb->entries++;

        return entry;
}

static void fabricate_dcb_output(struct dcb_table *dcb, int type, int i2c,
                                 int heads, int or)
{
        struct dcb_output *entry = new_dcb_entry(dcb);

        entry->type = type;
        entry->i2c_index = i2c;
        entry->heads = heads;
        if (type != DCB_OUTPUT_ANALOG)
                entry->location = !DCB_LOC_ON_CHIP; /* ie OFF CHIP */
        entry->or = or;
}

static bool
parse_dcb20_entry(struct drm_device *dev, struct dcb_table *dcb,
                  uint32_t conn, uint32_t conf, struct dcb_output *entry)
{
        struct nouveau_drm *drm = nouveau_drm(dev);

        entry->type = conn & 0xf;
        entry->i2c_index = (conn >> 4) & 0xf;
        entry->heads = (conn >> 8) & 0xf;
        entry->connector = (conn >> 12) & 0xf;
        entry->bus = (conn >> 16) & 0xf;
        entry->location = (conn >> 20) & 0x3;
        entry->or = (conn >> 24) & 0xf;

        switch (entry->type) {
        case DCB_OUTPUT_ANALOG:
                /*
                 * Although the rest of a CRT conf dword is usually
                 * zeros, mac biosen have stuff there so we must mask
                 */
                entry->crtconf.maxfreq = (dcb->version < 0x30) ?
                                         (conf & 0xffff) * 10 :
                                         (conf & 0xff) * 10000;
                break;
        case DCB_OUTPUT_LVDS:
                {
                uint32_t mask;
                if (conf & 0x1)
                        entry->lvdsconf.use_straps_for_mode = true;
                if (dcb->version < 0x22) {
                        mask = ~0xd;
                        /*
                         * The laptop in bug 14567 lies and claims to not use
                         * straps when it does, so assume all DCB 2.0 laptops
                         * use straps, until a broken EDID using one is produced
                         */
                        entry->lvdsconf.use_straps_for_mode = true;
                        /*
                         * Both 0x4 and 0x8 show up in v2.0 tables; assume they
                         * mean the same thing (probably wrong, but might work)
                         */
                        if (conf & 0x4 || conf & 0x8)
                                entry->lvdsconf.use_power_scripts = true;
                } else {
                        mask = ~0x7;
                        if (conf & 0x2)
                                entry->lvdsconf.use_acpi_for_edid = true;
                        if (conf & 0x4)
                                entry->lvdsconf.use_power_scripts = true;
                        entry->lvdsconf.sor.link = (conf & 0x00000030) >> 4;
                }
                if (conf & mask) {
                        /*
                         * Until we even try to use these on G8x, it's
                         * useless reporting unknown bits.  They all are.
                         */
                        if (dcb->version >= 0x40)
                                break;

                        NV_ERROR(drm, "Unknown LVDS configuration bits, "
                                      "please report\n");
                }
                break;
                }
        case DCB_OUTPUT_TV:
        {
                if (dcb->version >= 0x30)
                        entry->tvconf.has_component_output = conf & (0x8 << 4);
                else
                        entry->tvconf.has_component_output = false;

                break;
        }
        case DCB_OUTPUT_DP:
                entry->dpconf.sor.link = (conf & 0x00000030) >> 4;
                entry->extdev = (conf & 0x0000ff00) >> 8;
                switch ((conf & 0x00e00000) >> 21) {
                case 0:
                        entry->dpconf.link_bw = 162000;
                        break;
                default:
                        entry->dpconf.link_bw = 270000;
                        break;
                }
                switch ((conf & 0x0f000000) >> 24) {
                case 0xf:
                        entry->dpconf.link_nr = 4;
                        break;
                case 0x3:
                        entry->dpconf.link_nr = 2;
                        break;
                default:
                        entry->dpconf.link_nr = 1;
                        break;
                }
                break;
        case DCB_OUTPUT_TMDS:
                if (dcb->version >= 0x40) {
                        entry->tmdsconf.sor.link = (conf & 0x00000030) >> 4;
                        entry->extdev = (conf & 0x0000ff00) >> 8;
                }
                else if (dcb->version >= 0x30)
                        entry->tmdsconf.slave_addr = (conf & 0x00000700) >> 8;
                else if (dcb->version >= 0x22)
                        entry->tmdsconf.slave_addr = (conf & 0x00000070) >> 4;

                break;
        case DCB_OUTPUT_EOL:
                /* weird g80 mobile type that "nv" treats as a terminator */
                dcb->entries--;
                return false;
        default:
                break;
        }

        if (dcb->version < 0x40) {
                /* Normal entries consist of a single bit, but dual link has
                 * the next most significant bit set too
                 */
                entry->duallink_possible =
                        ((1 << (ffs(entry->or) - 1)) * 3 == entry->or);
        } else {
                entry->duallink_possible = (entry->sorconf.link == 3);
        }

        /* unsure what DCB version introduces this, 3.0? */
        if (conf & 0x100000)
                entry->i2c_upper_default = true;

        return true;
}

static bool
parse_dcb15_entry(struct drm_device *dev, struct dcb_table *dcb,
                  uint32_t conn, uint32_t conf, struct dcb_output *entry)
{
        struct nouveau_drm *drm = nouveau_drm(dev);

        switch (conn & 0x0000000f) {
        case 0:
                entry->type = DCB_OUTPUT_ANALOG;
                break;
        case 1:
                entry->type = DCB_OUTPUT_TV;
                break;
        case 2:
        case 4:
                if (conn & 0x10)
                        entry->type = DCB_OUTPUT_LVDS;
                else
                        entry->type = DCB_OUTPUT_TMDS;
                break;
        case 3:
                entry->type = DCB_OUTPUT_LVDS;
                break;
        default:
                NV_ERROR(drm, "Unknown DCB type %d\n", conn & 0x0000000f);
                return false;
        }

        entry->i2c_index = (conn & 0x0003c000) >> 14;
        entry->heads = ((conn & 0x001c0000) >> 18) + 1;
        entry->or = entry->heads; /* same as heads, hopefully safe enough */
        entry->location = (conn & 0x01e00000) >> 21;
        entry->bus = (conn & 0x0e000000) >> 25;
        entry->duallink_possible = false;

        switch (entry->type) {
        case DCB_OUTPUT_ANALOG:
                entry->crtconf.maxfreq = (conf & 0xffff) * 10;
                break;
        case DCB_OUTPUT_TV:
                entry->tvconf.has_component_output = false;
                break;
        case DCB_OUTPUT_LVDS:
                if ((conn & 0x00003f00) >> 8 != 0x10)
                        entry->lvdsconf.use_straps_for_mode = true;
                entry->lvdsconf.use_power_scripts = true;
                break;
        default:
                break;
        }

        return true;
}

static
void merge_like_dcb_entries(struct drm_device *dev, struct dcb_table *dcb)
{
        /*
         * DCB v2.0 lists each output combination separately.
         * Here we merge compatible entries to have fewer outputs, with
         * more options
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        int i, newentries = 0;

        for (i = 0; i < dcb->entries; i++) {
                struct dcb_output *ient = &dcb->entry[i];
                int j;

                for (j = i + 1; j < dcb->entries; j++) {
                        struct dcb_output *jent = &dcb->entry[j];

                        if (jent->type == 100) /* already merged entry */
                                continue;

                        /* merge heads field when all other fields the same */
                        if (jent->i2c_index == ient->i2c_index &&
                            jent->type == ient->type &&
                            jent->location == ient->location &&
                            jent->or == ient->or) {
                                NV_INFO(drm, "Merging DCB entries %d and %d\n",
                                         i, j);
                                ient->heads |= jent->heads;
                                jent->type = 100; /* dummy value */
                        }
                }
        }

        /* Compact entries merged into others out of dcb */
        for (i = 0; i < dcb->entries; i++) {
                if (dcb->entry[i].type == 100)
                        continue;

                if (newentries != i) {
                        dcb->entry[newentries] = dcb->entry[i];
                        dcb->entry[newentries].index = newentries;
                }
                newentries++;
        }

        dcb->entries = newentries;
}

static bool
apply_dcb_encoder_quirks(struct drm_device *dev, int idx, u32 *conn, u32 *conf)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct dcb_table *dcb = &drm->vbios.dcb;

        /* Dell Precision M6300
         *   DCB entry 2: 02025312 00000010
         *   DCB entry 3: 02026312 00000020
         *
         * Identical, except apparently a different connector on a
         * different SOR link.  Not a clue how we're supposed to know
         * which one is in use if it even shares an i2c line...
         *
         * Ignore the connector on the second SOR link to prevent
         * nasty problems until this is sorted (assuming it's not a
         * VBIOS bug).
         */
        if (nv_match_device(dev, 0x040d, 0x1028, 0x019b)) {
                if (*conn == 0x02026312 && *conf == 0x00000020)
                        return false;
        }

        /* GeForce3 Ti 200
         *
         * DCB reports an LVDS output that should be TMDS:
         *   DCB entry 1: f2005014 ffffffff
         */
        if (nv_match_device(dev, 0x0201, 0x1462, 0x8851)) {
                if (*conn == 0xf2005014 && *conf == 0xffffffff) {
                        fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 1, 1, 1);
                        return false;
                }
        }

        /* XFX GT-240X-YA
         *
         * So many things wrong here, replace the entire encoder table..
         */
        if (nv_match_device(dev, 0x0ca3, 0x1682, 0x3003)) {
                if (idx == 0) {
                        *conn = 0x02001300; /* VGA, connector 1 */
                        *conf = 0x00000028;
                } else
                if (idx == 1) {
                        *conn = 0x01010312; /* DVI, connector 0 */
                        *conf = 0x00020030;
                } else
                if (idx == 2) {
                        *conn = 0x01010310; /* VGA, connector 0 */
                        *conf = 0x00000028;
                } else
                if (idx == 3) {
                        *conn = 0x02022362; /* HDMI, connector 2 */
                        *conf = 0x00020010;
                } else {
                        *conn = 0x0000000e; /* EOL */
                        *conf = 0x00000000;
                }
        }

        /* Some other twisted XFX board (rhbz#694914)
         *
         * The DVI/VGA encoder combo that's supposed to represent the
         * DVI-I connector actually point at two different ones, and
         * the HDMI connector ends up paired with the VGA instead.
         *
         * Connector table is missing anything for VGA at all, pointing it
         * an invalid conntab entry 2 so we figure it out ourself.
         */
        if (nv_match_device(dev, 0x0615, 0x1682, 0x2605)) {
                if (idx == 0) {
                        *conn = 0x02002300; /* VGA, connector 2 */
                        *conf = 0x00000028;
                } else
                if (idx == 1) {
                        *conn = 0x01010312; /* DVI, connector 0 */
                        *conf = 0x00020030;
                } else
                if (idx == 2) {
                        *conn = 0x04020310; /* VGA, connector 0 */
                        *conf = 0x00000028;
                } else
                if (idx == 3) {
                        *conn = 0x02021322; /* HDMI, connector 1 */
                        *conf = 0x00020010;
                } else {
                        *conn = 0x0000000e; /* EOL */
                        *conf = 0x00000000;
                }
        }

        /* fdo#50830: connector indices for VGA and DVI-I are backwards */
        if (nv_match_device(dev, 0x0421, 0x3842, 0xc793)) {
                if (idx == 0 && *conn == 0x02000300)
                        *conn = 0x02011300;
                else
                if (idx == 1 && *conn == 0x04011310)
                        *conn = 0x04000310;
                else
                if (idx == 2 && *conn == 0x02011312)
                        *conn = 0x02000312;
        }

        return true;
}

static void
fabricate_dcb_encoder_table(struct drm_device *dev, struct nvbios *bios)
{
        struct dcb_table *dcb = &bios->dcb;
        int all_heads = (nv_two_heads(dev) ? 3 : 1);

#ifdef __powerpc__
        /* Apple iMac G4 NV17 */
        if (of_machine_is_compatible("PowerMac4,5")) {
                fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 0, all_heads, 1);
                fabricate_dcb_output(dcb, DCB_OUTPUT_ANALOG, 1, all_heads, 2);
                return;
        }
#endif

        /* Make up some sane defaults */
        fabricate_dcb_output(dcb, DCB_OUTPUT_ANALOG,
                             bios->legacy.i2c_indices.crt, 1, 1);

        if (nv04_tv_identify(dev, bios->legacy.i2c_indices.tv) >= 0)
                fabricate_dcb_output(dcb, DCB_OUTPUT_TV,
                                     bios->legacy.i2c_indices.tv,
                                     all_heads, 0);

        else if (bios->tmds.output0_script_ptr ||
                 bios->tmds.output1_script_ptr)
                fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS,
                                     bios->legacy.i2c_indices.panel,
                                     all_heads, 1);
}

static int
parse_dcb_entry(struct drm_device *dev, void *data, int idx, u8 *outp)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct dcb_table *dcb = &drm->vbios.dcb;
        u32 conf = (dcb->version >= 0x20) ? ROM32(outp[4]) : ROM32(outp[6]);
        u32 conn = ROM32(outp[0]);
        bool ret;

        if (apply_dcb_encoder_quirks(dev, idx, &conn, &conf)) {
                struct dcb_output *entry = new_dcb_entry(dcb);

                NV_INFO(drm, "DCB outp %02d: %08x %08x\n", idx, conn, conf);

                if (dcb->version >= 0x20)
                        ret = parse_dcb20_entry(dev, dcb, conn, conf, entry);
                else
                        ret = parse_dcb15_entry(dev, dcb, conn, conf, entry);
                if (!ret)
                        return 1; /* stop parsing */

                /* Ignore the I2C index for on-chip TV-out, as there
                 * are cards with bogus values (nv31m in bug 23212),
                 * and it's otherwise useless.
                 */
                if (entry->type == DCB_OUTPUT_TV &&
                    entry->location == DCB_LOC_ON_CHIP)
                        entry->i2c_index = 0x0f;
        }

        return 0;
}

static void
dcb_fake_connectors(struct nvbios *bios)
{
        struct dcb_table *dcbt = &bios->dcb;
        u8 map[16] = { };
        int i, idx = 0;

        /* heuristic: if we ever get a non-zero connector field, assume
         * that all the indices are valid and we don't need fake them.
         *
         * and, as usual, a blacklist of boards with bad bios data..
         */
        if (!nv_match_device(bios->dev, 0x0392, 0x107d, 0x20a2)) {
                for (i = 0; i < dcbt->entries; i++) {
                        if (dcbt->entry[i].connector)
                                return;
                }
        }

        /* no useful connector info available, we need to make it up
         * ourselves.  the rule here is: anything on the same i2c bus
         * is considered to be on the same connector.  any output
         * without an associated i2c bus is assigned its own unique
         * connector index.
         */
        for (i = 0; i < dcbt->entries; i++) {
                u8 i2c = dcbt->entry[i].i2c_index;
                if (i2c == 0x0f) {
                        dcbt->entry[i].connector = idx++;
                } else {
                        if (!map[i2c])
                                map[i2c] = ++idx;
                        dcbt->entry[i].connector = map[i2c] - 1;
                }
        }

        /* if we created more than one connector, destroy the connector
         * table - just in case it has random, rather than stub, entries.
         */
        if (i > 1) {
                u8 *conntab = olddcb_conntab(bios->dev);
                if (conntab)
                        conntab[0] = 0x00;
        }
}

static int
parse_dcb_table(struct drm_device *dev, struct nvbios *bios)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct dcb_table *dcb = &bios->dcb;
        u8 *dcbt, *conn;
        int idx;

        dcbt = olddcb_table(dev);
        if (!dcbt) {
                /* handle pre-DCB boards */
                if (bios->type == NVBIOS_BMP) {
                        fabricate_dcb_encoder_table(dev, bios);
                        return 0;
                }

                return -EINVAL;
        }

        NV_INFO(drm, "DCB version %d.%d\n", dcbt[0] >> 4, dcbt[0] & 0xf);

        dcb->version = dcbt[0];
        olddcb_outp_foreach(dev, NULL, parse_dcb_entry);

        /*
         * apart for v2.1+ not being known for requiring merging, this
         * guarantees dcbent->index is the index of the entry in the rom image
         */
        if (dcb->version < 0x21)
                merge_like_dcb_entries(dev, dcb);

        /* dump connector table entries to log, if any exist */
        idx = -1;
        while ((conn = olddcb_conn(dev, ++idx))) {
                if (conn[0] != 0xff) {
                        NV_INFO(drm, "DCB conn %02d: ", idx);
                        if (olddcb_conntab(dev)[3] < 4)
                                pr_cont("%04x\n", ROM16(conn[0]));
                        else
                                pr_cont("%08x\n", ROM32(conn[0]));
                }
        }
        dcb_fake_connectors(bios);
        return 0;
}

static int load_nv17_hwsq_ucode_entry(struct drm_device *dev, struct nvbios *bios, uint16_t hwsq_offset, int entry)
{
        /*
         * The header following the "HWSQ" signature has the number of entries,
         * and the entry size
         *
         * An entry consists of a dword to write to the sequencer control reg
         * (0x00001304), followed by the ucode bytes, written sequentially,
         * starting at reg 0x00001400
         */

        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_device *device = nv_device(drm->device);
        uint8_t bytes_to_write;
        uint16_t hwsq_entry_offset;
        int i;

        if (bios->data[hwsq_offset] <= entry) {
                NV_ERROR(drm, "Too few entries in HW sequencer table for "
                                "requested entry\n");
                return -ENOENT;
        }

        bytes_to_write = bios->data[hwsq_offset + 1];

        if (bytes_to_write != 36) {
                NV_ERROR(drm, "Unknown HW sequencer entry size\n");
                return -EINVAL;
        }

        NV_INFO(drm, "Loading NV17 power sequencing microcode\n");

        hwsq_entry_offset = hwsq_offset + 2 + entry * bytes_to_write;

        /* set sequencer control */
        nv_wr32(device, 0x00001304, ROM32(bios->data[hwsq_entry_offset]));
        bytes_to_write -= 4;

        /* write ucode */
        for (i = 0; i < bytes_to_write; i += 4)
                nv_wr32(device, 0x00001400 + i, ROM32(bios->data[hwsq_entry_offset + i + 4]));

        /* twiddle NV_PBUS_DEBUG_4 */
        nv_wr32(device, NV_PBUS_DEBUG_4, nv_rd32(device, NV_PBUS_DEBUG_4) | 0x18);

        return 0;
}

static int load_nv17_hw_sequencer_ucode(struct drm_device *dev,
                                        struct nvbios *bios)
{
        /*
         * BMP based cards, from NV17, need a microcode loading to correctly
         * control the GPIO etc for LVDS panels
         *
         * BIT based cards seem to do this directly in the init scripts
         *
         * The microcode entries are found by the "HWSQ" signature.
         */

        const uint8_t hwsq_signature[] = { 'H', 'W', 'S', 'Q' };
        const int sz = sizeof(hwsq_signature);
        int hwsq_offset;

        hwsq_offset = findstr(bios->data, bios->length, hwsq_signature, sz);
        if (!hwsq_offset)
                return 0;

        /* always use entry 0? */
        return load_nv17_hwsq_ucode_entry(dev, bios, hwsq_offset + sz, 0);
}

uint8_t *nouveau_bios_embedded_edid(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        const uint8_t edid_sig[] = {
                        0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00 };
        uint16_t offset = 0;
        uint16_t newoffset;
        int searchlen = NV_PROM_SIZE;

        if (bios->fp.edid)
                return bios->fp.edid;

        while (searchlen) {
                newoffset = findstr(&bios->data[offset], searchlen,
                                                                edid_sig, 8);
                if (!newoffset)
                        return NULL;
                offset += newoffset;
                if (!nv_cksum(&bios->data[offset], EDID1_LEN))
                        break;

                searchlen -= offset;
                offset++;
        }

        NV_INFO(drm, "Found EDID in BIOS\n");

        return bios->fp.edid = &bios->data[offset];
}

static bool NVInitVBIOS(struct drm_device *dev)
{

        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_bios *bios = nouveau_bios(drm->device);
        struct nvbios *legacy = &drm->vbios;

        memset(legacy, 0, sizeof(struct nvbios));
        spin_lock_init(&legacy->lock);
        legacy->dev = dev;

        legacy->data = bios->data;
        legacy->length = bios->size;
        legacy->major_version = bios->version.major;
        legacy->chip_version = bios->version.chip;
        if (bios->bit_offset) {
                legacy->type = NVBIOS_BIT;
                legacy->offset = bios->bit_offset;
                return !parse_bit_structure(legacy, legacy->offset + 6);
        } else
        if (bios->bmp_offset) {
                legacy->type = NVBIOS_BMP;
                legacy->offset = bios->bmp_offset;
                return !parse_bmp_structure(dev, legacy, legacy->offset);
        }

        return false;
}

int
nouveau_run_vbios_init(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        int ret = 0;

        /* Reset the BIOS head to 0. */
        bios->state.crtchead = 0;

        if (bios->major_version < 5)    /* BMP only */
                load_nv17_hw_sequencer_ucode(dev, bios);

        if (bios->execute) {
                bios->fp.last_script_invoc = 0;
                bios->fp.lvds_init_run = false;
        }

        return ret;
}

static bool
nouveau_bios_posted(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        unsigned htotal;

        if (nv_device(drm->device)->card_type >= NV_50)
                return true;

        htotal  = NVReadVgaCrtc(dev, 0, 0x06);
        htotal |= (NVReadVgaCrtc(dev, 0, 0x07) & 0x01) << 8;
        htotal |= (NVReadVgaCrtc(dev, 0, 0x07) & 0x20) << 4;
        htotal |= (NVReadVgaCrtc(dev, 0, 0x25) & 0x01) << 10;
        htotal |= (NVReadVgaCrtc(dev, 0, 0x41) & 0x01) << 11;
        return (htotal != 0);
}

int
nouveau_bios_init(struct drm_device *dev)
{
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvbios *bios = &drm->vbios;
        int ret;

        if (!NVInitVBIOS(dev))
                return -ENODEV;

        ret = parse_dcb_table(dev, bios);
        if (ret)
                return ret;

        if (!bios->major_version)       /* we don't run version 0 bios */
                return 0;

        /* init script execution disabled */
        bios->execute = false;

        /* ... unless card isn't POSTed already */
        if (!nouveau_bios_posted(dev)) {
                NV_INFO(drm, "Adaptor not initialised, "
                        "running VBIOS init tables.\n");
                bios->execute = true;
        }

        ret = nouveau_run_vbios_init(dev);
        if (ret)
                return ret;

        /* feature_byte on BMP is poor, but init always sets CR4B */
        if (bios->major_version < 5)
                bios->is_mobile = NVReadVgaCrtc(dev, 0, NV_CIO_CRE_4B) & 0x40;

        /* all BIT systems need p_f_m_t for digital_min_front_porch */
        if (bios->is_mobile || bios->major_version >= 5)
                ret = parse_fp_mode_table(dev, bios);

        /* allow subsequent scripts to execute */
        bios->execute = true;

        return 0;
}

void
nouveau_bios_takedown(struct drm_device *dev)
{
}