/*
 * Copyright © 2006 Intel Corporation
 *
 * 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 (including the next
 * paragraph) 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 OR COPYRIGHT HOLDERS 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.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */
#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.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 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;

        /* 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);
}

/* Try to find integrated panel data */
static void
parse_lfp_panel_data(struct drm_i915_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_ptrs *lvds_lfp_data_ptrs;
        struct bdb_lvds_lfp_data_entry *entry;
        struct lvds_dvo_timing *dvo_timing;
        struct drm_display_mode *panel_fixed_mode;
        int lfp_data_size, dvo_timing_offset;

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

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

        lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
        if (!lvds_lfp_data_ptrs)
                return;

        dev_priv->lvds_vbt = 1;

        lfp_data_size = lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
                lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
        entry = (struct bdb_lvds_lfp_data_entry *)
                ((uint8_t *)lvds_lfp_data->data + (lfp_data_size *
                                                   lvds_options->panel_type));
        dvo_timing_offset = lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
                lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;

        /*
         * the size of fp_timing varies on the different platform.
         * So calculate the DVO timing relative offset in LVDS data
         * entry to get the DVO timing entry
         */
        dvo_timing = (struct lvds_dvo_timing *)
                        ((unsigned char *)entry + dvo_timing_offset);

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

        fill_detail_timing_data(panel_fixed_mode, dvo_timing);

        dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;

        DRM_DEBUG("Found panel mode in BIOS VBT tables:\n");
        drm_mode_debug_printmodeline(panel_fixed_mode);

        return;
}

/* Try to find sdvo panel data */
static void
parse_sdvo_panel_data(struct drm_i915_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_i915_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) {
                        if (IS_I85X(dev_priv->dev))
                                dev_priv->lvds_ssc_freq =
                                        general->ssc_freq ? 66 : 48;
                        else if (IS_IGDNG(dev_priv->dev))
                                dev_priv->lvds_ssc_freq =
                                        general->ssc_freq ? 100 : 120;
                        else
                                dev_priv->lvds_ssc_freq =
                                        general->ssc_freq ? 100 : 96;
                }
        }
}

static void
parse_general_definitions(struct drm_i915_private *dev_priv,
                          struct bdb_header *bdb)
{
        struct bdb_general_definitions *general;
        const int crt_bus_map_table[] = {
                GPIOB,
                GPIOA,
                GPIOC,
                GPIOD,
                GPIOE,
                GPIOF,
        };

        /* Set sensible defaults in case we can't find the general block
           or it is the wrong chipset */
        dev_priv->crt_ddc_bus = -1;

        general = find_section(bdb, BDB_GENERAL_DEFINITIONS);
        if (general) {
                u16 block_size = get_blocksize(general);
                if (block_size >= sizeof(*general)) {
                        int bus_pin = general->crt_ddc_gmbus_pin;
                        DRM_DEBUG("crt_ddc_bus_pin: %d\n", bus_pin);
                        if ((bus_pin >= 1) && (bus_pin <= 6)) {
                                dev_priv->crt_ddc_bus =
                                        crt_bus_map_table[bus_pin-1];
                        }
                } else {
                        DRM_DEBUG("BDB_GD too small (%d). Invalid.\n",
                                  block_size);
                }
        }
}

static void
parse_sdvo_device_mapping(struct drm_i915_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("No general definition block is found\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("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("Incorrect SDVO port. Skip it \n");
                        continue;
                }
                DRM_DEBUG("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->initialized = 1;
                } else {
                        DRM_DEBUG("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("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("No SDVO device info is found in VBT\n");
        }
        return;
}

static void
parse_driver_features(struct drm_i915_private *dev_priv,
                       struct bdb_header *bdb)
{
        struct drm_device *dev = dev_priv->dev;
        struct bdb_driver_features *driver;

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

        if (driver && SUPPORTS_EDP(dev) &&
            driver->lvds_config == BDB_DRIVER_FEATURE_EDP) {
                dev_priv->edp_support = 1;
        } else {
                dev_priv->edp_support = 0;
        }

        if (driver && driver->dual_frequency)
                dev_priv->render_reclock_avail = true;
}

/**
 * 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.
 */
bool
intel_init_bios(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct pci_dev *pdev = dev->pdev;
        struct vbt_header *vbt = NULL;
        struct bdb_header *bdb;
        u8 __iomem *bios;
        size_t size;
        int i;

        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) {
                DRM_ERROR("VBT signature missing\n");
                pci_unmap_rom(pdev, bios);
                return -1;
        }

        bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);

        /* Grab useful general definitions */
        parse_general_features(dev_priv, bdb);
        parse_general_definitions(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_driver_features(dev_priv, bdb);

        pci_unmap_rom(pdev, bios);

        return 0;
}