/*
 * Copyright (c) 2006 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */
#include <drm/drmP.h>
#include <drm/drm.h>
#include <drm/gma_drm.h>
#include "psb_drv.h"
#include "psb_intel_drv.h"
#include "psb_intel_reg.h"
#include "intel_bios.h"

#define SLAVE_ADDR1     0x70
#define SLAVE_ADDR2     0x72

static void *find_section(struct bdb_header *bdb, int section_id)
{
        u8 *base = (u8 *)bdb;
        int index = 0;
        u16 total, current_size;
        u8 current_id;

        /* skip to first section */
        index += bdb->header_size;
        total = bdb->bdb_size;

        /* walk the sections looking for section_id */
        while (index < total) {
                current_id = *(base + index);
                index++;
                current_size = *((u16 *)(base + index));
                index += 2;
                if (current_id == section_id)
                        return base + index;
                index += current_size;
        }

        return NULL;
}

static void
parse_edp(struct drm_psb_private *dev_priv, struct bdb_header *bdb)
{
        struct bdb_edp *edp;
        struct edp_power_seq *edp_pps;
        struct edp_link_params *edp_link_params;
        uint8_t panel_type;

        edp = find_section(bdb, BDB_EDP);
        
        dev_priv->edp.bpp = 18;
        if (!edp) {
                if (dev_priv->edp.support) {
                        DRM_DEBUG_KMS("No eDP BDB found but eDP panel supported, assume %dbpp panel color depth.\n",
                                      dev_priv->edp.bpp);
                }
                return;
        }

        panel_type = dev_priv->panel_type;
        switch ((edp->color_depth >> (panel_type * 2)) & 3) {
        case EDP_18BPP:
                dev_priv->edp.bpp = 18;
                break;
        case EDP_24BPP:
                dev_priv->edp.bpp = 24;
                break;
        case EDP_30BPP:
                dev_priv->edp.bpp = 30;
                break;
        }

        /* Get the eDP sequencing and link info */
        edp_pps = &edp->power_seqs[panel_type];
        edp_link_params = &edp->link_params[panel_type];

        dev_priv->edp.pps = *edp_pps;

        DRM_DEBUG_KMS("EDP timing in vbt t1_t3 %d t8 %d t9 %d t10 %d t11_t12 %d\n",
                                dev_priv->edp.pps.t1_t3, dev_priv->edp.pps.t8, 
                                dev_priv->edp.pps.t9, dev_priv->edp.pps.t10,
                                dev_priv->edp.pps.t11_t12);

        dev_priv->edp.rate = edp_link_params->rate ? DP_LINK_BW_2_7 :
                DP_LINK_BW_1_62;
        switch (edp_link_params->lanes) {
        case 0:
                dev_priv->edp.lanes = 1;
                break;
        case 1:
                dev_priv->edp.lanes = 2;
                break;
        case 3:
        default:
                dev_priv->edp.lanes = 4;
                break;
        }
        DRM_DEBUG_KMS("VBT reports EDP: Lane_count %d, Lane_rate %d, Bpp %d\n",
                        dev_priv->edp.lanes, dev_priv->edp.rate, dev_priv->edp.bpp);

        switch (edp_link_params->preemphasis) {
        case 0:
                dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_0;
                break;
        case 1:
                dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_3_5;
                break;
        case 2:
                dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_6;
                break;
        case 3:
                dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_9_5;
                break;
        }
        switch (edp_link_params->vswing) {
        case 0:
                dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_400;
                break;
        case 1:
                dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_600;
                break;
        case 2:
                dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_800;
                break;
        case 3:
                dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_1200;
                break;
        }
        DRM_DEBUG_KMS("VBT reports EDP: VSwing  %d, Preemph %d\n",
                        dev_priv->edp.vswing, dev_priv->edp.preemphasis);
}

static u16
get_blocksize(void *p)
{
        u16 *block_ptr, block_size;

        block_ptr = (u16 *)((char *)p - 2);
        block_size = *block_ptr;
        return block_size;
}

static void fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
                        struct lvds_dvo_timing *dvo_timing)
{
        panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
                dvo_timing->hactive_lo;
        panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
                ((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
        panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
                dvo_timing->hsync_pulse_width;
        panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
                ((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);

        panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
                dvo_timing->vactive_lo;
        panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
                dvo_timing->vsync_off;
        panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
                dvo_timing->vsync_pulse_width;
        panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
                ((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
        panel_fixed_mode->clock = dvo_timing->clock * 10;
        panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;

        if (dvo_timing->hsync_positive)
                panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
        else
                panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;

        if (dvo_timing->vsync_positive)
                panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
        else
                panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;

        /* Some VBTs have bogus h/vtotal values */
        if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
                panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
        if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
                panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;

        drm_mode_set_name(panel_fixed_mode);
}

static void parse_backlight_data(struct drm_psb_private *dev_priv,
                                struct bdb_header *bdb)
{
        struct bdb_lvds_backlight *vbt_lvds_bl = NULL;
        struct bdb_lvds_backlight *lvds_bl;
        u8 p_type = 0;
        void *bl_start = NULL;
        struct bdb_lvds_options *lvds_opts
                                = find_section(bdb, BDB_LVDS_OPTIONS);

        dev_priv->lvds_bl = NULL;

        if (lvds_opts)
                p_type = lvds_opts->panel_type;
        else
                return;

        bl_start = find_section(bdb, BDB_LVDS_BACKLIGHT);
        vbt_lvds_bl = (struct bdb_lvds_backlight *)(bl_start + 1) + p_type;

        lvds_bl = kzalloc(sizeof(*vbt_lvds_bl), GFP_KERNEL);
        if (!lvds_bl) {
                dev_err(dev_priv->dev->dev, "out of memory for backlight data\n");
                return;
        }
        memcpy(lvds_bl, vbt_lvds_bl, sizeof(*vbt_lvds_bl));
        dev_priv->lvds_bl = lvds_bl;
}

/* Try to find integrated panel data */
static void parse_lfp_panel_data(struct drm_psb_private *dev_priv,
                            struct bdb_header *bdb)
{
        struct bdb_lvds_options *lvds_options;
        struct bdb_lvds_lfp_data *lvds_lfp_data;
        struct bdb_lvds_lfp_data_entry *entry;
        struct lvds_dvo_timing *dvo_timing;
        struct drm_display_mode *panel_fixed_mode;

        /* Defaults if we can't find VBT info */
        dev_priv->lvds_dither = 0;
        dev_priv->lvds_vbt = 0;

        lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
        if (!lvds_options)
                return;

        dev_priv->lvds_dither = lvds_options->pixel_dither;
        dev_priv->panel_type = lvds_options->panel_type;

        if (lvds_options->panel_type == 0xff)
                return;

        lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
        if (!lvds_lfp_data)
                return;


        entry = &lvds_lfp_data->data[lvds_options->panel_type];
        dvo_timing = &entry->dvo_timing;

        panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode),
                                      GFP_KERNEL);
        if (panel_fixed_mode == NULL) {
                dev_err(dev_priv->dev->dev, "out of memory for fixed panel mode\n");
                return;
        }

        dev_priv->lvds_vbt = 1;
        fill_detail_timing_data(panel_fixed_mode, dvo_timing);

        if (panel_fixed_mode->htotal > 0 && panel_fixed_mode->vtotal > 0) {
                dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;
                drm_mode_debug_printmodeline(panel_fixed_mode);
        } else {
                dev_dbg(dev_priv->dev->dev, "ignoring invalid LVDS VBT\n");
                dev_priv->lvds_vbt = 0;
                kfree(panel_fixed_mode);
        }
        return;
}

/* Try to find sdvo panel data */
static void parse_sdvo_panel_data(struct drm_psb_private *dev_priv,
                      struct bdb_header *bdb)
{
        struct bdb_sdvo_lvds_options *sdvo_lvds_options;
        struct lvds_dvo_timing *dvo_timing;
        struct drm_display_mode *panel_fixed_mode;

        dev_priv->sdvo_lvds_vbt_mode = NULL;

        sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
        if (!sdvo_lvds_options)
                return;

        dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
        if (!dvo_timing)
                return;

        panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);

        if (!panel_fixed_mode)
                return;

        fill_detail_timing_data(panel_fixed_mode,
                        dvo_timing + sdvo_lvds_options->panel_type);

        dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode;

        return;
}

static void parse_general_features(struct drm_psb_private *dev_priv,
                       struct bdb_header *bdb)
{
        struct bdb_general_features *general;

        /* Set sensible defaults in case we can't find the general block */
        dev_priv->int_tv_support = 1;
        dev_priv->int_crt_support = 1;

        general = find_section(bdb, BDB_GENERAL_FEATURES);
        if (general) {
                dev_priv->int_tv_support = general->int_tv_support;
                dev_priv->int_crt_support = general->int_crt_support;
                dev_priv->lvds_use_ssc = general->enable_ssc;

                if (dev_priv->lvds_use_ssc) {
                        dev_priv->lvds_ssc_freq
                                = general->ssc_freq ? 100 : 96;
                }
        }
}

static void
parse_sdvo_device_mapping(struct drm_psb_private *dev_priv,
                          struct bdb_header *bdb)
{
        struct sdvo_device_mapping *p_mapping;
        struct bdb_general_definitions *p_defs;
        struct child_device_config *p_child;
        int i, child_device_num, count;
        u16     block_size;

        p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
        if (!p_defs) {
                DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");
                return;
        }
        /* judge whether the size of child device meets the requirements.
         * If the child device size obtained from general definition block
         * is different with sizeof(struct child_device_config), skip the
         * parsing of sdvo device info
         */
        if (p_defs->child_dev_size != sizeof(*p_child)) {
                /* different child dev size . Ignore it */
                DRM_DEBUG_KMS("different child size is found. Invalid.\n");
                return;
        }
        /* get the block size of general definitions */
        block_size = get_blocksize(p_defs);
        /* get the number of child device */
        child_device_num = (block_size - sizeof(*p_defs)) /
                                sizeof(*p_child);
        count = 0;
        for (i = 0; i < child_device_num; i++) {
                p_child = &(p_defs->devices[i]);
                if (!p_child->device_type) {
                        /* skip the device block if device type is invalid */
                        continue;
                }
                if (p_child->slave_addr != SLAVE_ADDR1 &&
                        p_child->slave_addr != SLAVE_ADDR2) {
                        /*
                         * If the slave address is neither 0x70 nor 0x72,
                         * it is not a SDVO device. Skip it.
                         */
                        continue;
                }
                if (p_child->dvo_port != DEVICE_PORT_DVOB &&
                        p_child->dvo_port != DEVICE_PORT_DVOC) {
                        /* skip the incorrect SDVO port */
                        DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
                        continue;
                }
                DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
                                " %s port\n",
                                p_child->slave_addr,
                                (p_child->dvo_port == DEVICE_PORT_DVOB) ?
                                        "SDVOB" : "SDVOC");
                p_mapping = &(dev_priv->sdvo_mappings[p_child->dvo_port - 1]);
                if (!p_mapping->initialized) {
                        p_mapping->dvo_port = p_child->dvo_port;
                        p_mapping->slave_addr = p_child->slave_addr;
                        p_mapping->dvo_wiring = p_child->dvo_wiring;
                        p_mapping->ddc_pin = p_child->ddc_pin;
                        p_mapping->i2c_pin = p_child->i2c_pin;
                        p_mapping->initialized = 1;
                        DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
                                      p_mapping->dvo_port,
                                      p_mapping->slave_addr,
                                      p_mapping->dvo_wiring,
                                      p_mapping->ddc_pin,
                                      p_mapping->i2c_pin);
                } else {
                        DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
                                         "two SDVO device.\n");
                }
                if (p_child->slave2_addr) {
                        /* Maybe this is a SDVO device with multiple inputs */
                        /* And the mapping info is not added */
                        DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
                                " is a SDVO device with multiple inputs.\n");
                }
                count++;
        }

        if (!count) {
                /* No SDVO device info is found */
                DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
        }
        return;
}


static void
parse_driver_features(struct drm_psb_private *dev_priv,
                      struct bdb_header *bdb)
{
        struct bdb_driver_features *driver;

        driver = find_section(bdb, BDB_DRIVER_FEATURES);
        if (!driver)
                return;

        if (driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
                dev_priv->edp.support = 1;

        /* This bit means to use 96Mhz for DPLL_A or not */
        if (driver->primary_lfp_id)
                dev_priv->dplla_96mhz = true;
        else
                dev_priv->dplla_96mhz = false;
}

static void
parse_device_mapping(struct drm_psb_private *dev_priv,
                       struct bdb_header *bdb)
{
        struct bdb_general_definitions *p_defs;
        struct child_device_config *p_child, *child_dev_ptr;
        int i, child_device_num, count;
        u16     block_size;

        p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
        if (!p_defs) {
                DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
                return;
        }
        /* judge whether the size of child device meets the requirements.
         * If the child device size obtained from general definition block
         * is different with sizeof(struct child_device_config), skip the
         * parsing of sdvo device info
         */
        if (p_defs->child_dev_size != sizeof(*p_child)) {
                /* different child dev size . Ignore it */
                DRM_DEBUG_KMS("different child size is found. Invalid.\n");
                return;
        }
        /* get the block size of general definitions */
        block_size = get_blocksize(p_defs);
        /* get the number of child device */
        child_device_num = (block_size - sizeof(*p_defs)) /
                                sizeof(*p_child);
        count = 0;
        /* get the number of child devices that are present */
        for (i = 0; i < child_device_num; i++) {
                p_child = &(p_defs->devices[i]);
                if (!p_child->device_type) {
                        /* skip the device block if device type is invalid */
                        continue;
                }
                count++;
        }
        if (!count) {
                DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
                return;
        }
        dev_priv->child_dev = kcalloc(count, sizeof(*p_child), GFP_KERNEL);
        if (!dev_priv->child_dev) {
                DRM_DEBUG_KMS("No memory space for child devices\n");
                return;
        }

        dev_priv->child_dev_num = count;
        count = 0;
        for (i = 0; i < child_device_num; i++) {
                p_child = &(p_defs->devices[i]);
                if (!p_child->device_type) {
                        /* skip the device block if device type is invalid */
                        continue;
                }
                child_dev_ptr = dev_priv->child_dev + count;
                count++;
                memcpy((void *)child_dev_ptr, (void *)p_child,
                                        sizeof(*p_child));
        }
        return;
}


/**
 * psb_intel_init_bios - initialize VBIOS settings & find VBT
 * @dev: DRM device
 *
 * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
 * to appropriate values.
 *
 * VBT existence is a sanity check that is relied on by other i830_bios.c code.
 * Note that it would be better to use a BIOS call to get the VBT, as BIOSes may
 * feed an updated VBT back through that, compared to what we'll fetch using
 * this method of groping around in the BIOS data.
 *
 * Returns 0 on success, nonzero on failure.
 */
int psb_intel_init_bios(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;
        struct pci_dev *pdev = dev->pdev;
        struct vbt_header *vbt = NULL;
        struct bdb_header *bdb = NULL;
        u8 __iomem *bios = NULL;
        size_t size;
        int i;


        dev_priv->panel_type = 0xff;

        /* XXX Should this validation be moved to intel_opregion.c? */
        if (dev_priv->opregion.vbt) {
                struct vbt_header *vbt = dev_priv->opregion.vbt;
                if (memcmp(vbt->signature, "$VBT", 4) == 0) {
                        DRM_DEBUG_KMS("Using VBT from OpRegion: %20s\n",
                                         vbt->signature);
                        bdb = (struct bdb_header *)((char *)vbt + vbt->bdb_offset);
                } else
                        dev_priv->opregion.vbt = NULL;
        }

        if (bdb == NULL) {
                bios = pci_map_rom(pdev, &size);
                if (!bios)
                        return -1;

                /* Scour memory looking for the VBT signature */
                for (i = 0; i + 4 < size; i++) {
                        if (!memcmp(bios + i, "$VBT", 4)) {
                                vbt = (struct vbt_header *)(bios + i);
                                break;
                        }
                }

                if (!vbt) {
                        dev_err(dev->dev, "VBT signature missing\n");
                        pci_unmap_rom(pdev, bios);
                        return -1;
                }
                bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);
        }

        /* Grab useful general dxefinitions */
        parse_general_features(dev_priv, bdb);
        parse_driver_features(dev_priv, bdb);
        parse_lfp_panel_data(dev_priv, bdb);
        parse_sdvo_panel_data(dev_priv, bdb);
        parse_sdvo_device_mapping(dev_priv, bdb);
        parse_device_mapping(dev_priv, bdb);
        parse_backlight_data(dev_priv, bdb);
        parse_edp(dev_priv, bdb);

        if (bios)
                pci_unmap_rom(pdev, bios);

        return 0;
}

/**
 * Destroy and free VBT data
 */
void psb_intel_destroy_bios(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;

        kfree(dev_priv->sdvo_lvds_vbt_mode);
        kfree(dev_priv->lfp_lvds_vbt_mode);
        kfree(dev_priv->lvds_bl);
}