/*
 * Copyright 2012 Red Hat Inc.
 *
 * 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 */
/*
 * Authors: Dave Airlie <airlied@redhat.com>
 */

#include <linux/aperture.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pci.h>

#include <drm/clients/drm_client_setup.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fbdev_shmem.h>
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_module.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>

#include "ast_drv.h"

static int ast_modeset = -1;

MODULE_PARM_DESC(modeset, "Disable/Enable modesetting");
module_param_named(modeset, ast_modeset, int, 0400);

void ast_device_init(struct ast_device *ast,
                     enum ast_chip chip,
                     enum ast_config_mode config_mode,
                     void __iomem *regs,
                     void __iomem *ioregs,
                     const struct ast_device_quirks *quirks)
{
        ast->quirks = quirks;
        ast->chip = chip;
        ast->config_mode = config_mode;
        ast->regs = regs;
        ast->ioregs = ioregs;
}

void __ast_device_set_tx_chip(struct ast_device *ast, enum ast_tx_chip tx_chip)
{
        static const char * const info_str[] = {
                "analog VGA",
                "Sil164 TMDS transmitter",
                "DP501 DisplayPort transmitter",
                "ASPEED DisplayPort transmitter",
        };

        drm_info(&ast->base, "Using %s\n", info_str[tx_chip]);

        ast->tx_chip = tx_chip;
}

/*
 * DRM driver
 */

DEFINE_DRM_GEM_FOPS(ast_fops);

static const struct drm_driver ast_driver = {
        .driver_features = DRIVER_ATOMIC |
                           DRIVER_GEM |
                           DRIVER_MODESET,

        .fops = &ast_fops,
        .name = DRIVER_NAME,
        .desc = DRIVER_DESC,
        .major = DRIVER_MAJOR,
        .minor = DRIVER_MINOR,
        .patchlevel = DRIVER_PATCHLEVEL,

        DRM_GEM_SHMEM_DRIVER_OPS,
        DRM_FBDEV_SHMEM_DRIVER_OPS,
};

/*
 * PCI driver
 */

#define PCI_VENDOR_ASPEED 0x1a03

#define AST_VGA_DEVICE(id, info) {              \
        .class = PCI_BASE_CLASS_DISPLAY << 16,  \
        .class_mask = 0xff0000,                 \
        .vendor = PCI_VENDOR_ASPEED,                    \
        .device = id,                           \
        .subvendor = PCI_ANY_ID,                \
        .subdevice = PCI_ANY_ID,                \
        .driver_data = (unsigned long) info }

static const struct pci_device_id ast_pciidlist[] = {
        AST_VGA_DEVICE(PCI_CHIP_AST2000, NULL),
        AST_VGA_DEVICE(PCI_CHIP_AST2100, NULL),
        {0, 0, 0},
};

MODULE_DEVICE_TABLE(pci, ast_pciidlist);

static bool ast_is_vga_enabled(void __iomem *ioregs)
{
        u8 vgaer = __ast_read8(ioregs, AST_IO_VGAER);

        return vgaer & AST_IO_VGAER_VGA_ENABLE;
}

static void ast_enable_vga(void __iomem *ioregs)
{
        __ast_write8(ioregs, AST_IO_VGAER, AST_IO_VGAER_VGA_ENABLE);
        __ast_write8(ioregs, AST_IO_VGAMR_W, AST_IO_VGAMR_IOSEL);
}

/*
 * Run this function as part of the HW device cleanup; not
 * when the DRM device gets released.
 */
static void ast_enable_mmio_release(void *data)
{
        void __iomem *ioregs = (void __force __iomem *)data;

        /* enable standard VGA decode */
        __ast_write8_i(ioregs, AST_IO_VGACRI, 0xa1, AST_IO_VGACRA1_MMIO_ENABLED);
}

static int ast_enable_mmio(struct device *dev, void __iomem *ioregs)
{
        void *data = (void __force *)ioregs;

        __ast_write8_i(ioregs, AST_IO_VGACRI, 0xa1,
                       AST_IO_VGACRA1_MMIO_ENABLED |
                       AST_IO_VGACRA1_VGAIO_DISABLED);

        return devm_add_action_or_reset(dev, ast_enable_mmio_release, data);
}

static void ast_open_key(void __iomem *ioregs)
{
        __ast_write8_i(ioregs, AST_IO_VGACRI, 0x80, AST_IO_VGACR80_PASSWORD);
}

static int ast_detect_chip(struct pci_dev *pdev,
                           void __iomem *regs, void __iomem *ioregs,
                           enum ast_chip *chip_out,
                           enum ast_config_mode *config_mode_out)
{
        struct device *dev = &pdev->dev;
        struct device_node *np = dev->of_node;
        enum ast_config_mode config_mode = ast_use_defaults;
        uint32_t scu_rev = 0xffffffff;
        enum ast_chip chip;
        u32 data;
        u8 vgacrd0, vgacrd1;

        /*
         * Find configuration mode and read SCU revision
         */

        /* Check if we have device-tree properties */
        if (np && !of_property_read_u32(np, "aspeed,scu-revision-id", &data)) {
                /* We do, disable P2A access */
                config_mode = ast_use_dt;
                scu_rev = data;
        } else if (pdev->device == PCI_CHIP_AST2000) { // Not all families have a P2A bridge
                /*
                 * The BMC will set SCU 0x40 D[12] to 1 if the P2 bridge
                 * is disabled. We force using P2A if VGA only mode bit
                 * is set D[7]
                 */
                vgacrd0 = __ast_read8_i(ioregs, AST_IO_VGACRI, 0xd0);
                vgacrd1 = __ast_read8_i(ioregs, AST_IO_VGACRI, 0xd1);
                if (!(vgacrd0 & 0x80) || !(vgacrd1 & 0x10)) {

                        /*
                         * We have a P2A bridge and it is enabled.
                         */

                        /* Patch AST2500/AST2510 */
                        if ((pdev->revision & 0xf0) == 0x40) {
                                if (!(vgacrd0 & AST_IO_VGACRD0_VRAM_INIT_STATUS_MASK))
                                        ast_2500_patch_ahb(regs);
                        }

                        /* Double check that it's actually working */
                        data = __ast_read32(regs, 0xf004);
                        if ((data != 0xffffffff) && (data != 0x00)) {
                                config_mode = ast_use_p2a;

                                /* Read SCU7c (silicon revision register) */
                                __ast_write32(regs, 0xf004, 0x1e6e0000);
                                __ast_write32(regs, 0xf000, 0x1);
                                scu_rev = __ast_read32(regs, 0x1207c);
                        }
                }
        }

        switch (config_mode) {
        case ast_use_defaults:
                dev_info(dev, "Using default configuration\n");
                break;
        case ast_use_dt:
                dev_info(dev, "Using device-tree for configuration\n");
                break;
        case ast_use_p2a:
                dev_info(dev, "Using P2A bridge for configuration\n");
                break;
        }

        /*
         * Identify chipset
         */

        if (pdev->revision >= 0x50) {
                chip = AST2600;
                dev_info(dev, "AST 2600 detected\n");
        } else if (pdev->revision >= 0x40) {
                switch (scu_rev & 0x300) {
                case 0x0100:
                        chip = AST2510;
                        dev_info(dev, "AST 2510 detected\n");
                        break;
                default:
                        chip = AST2500;
                        dev_info(dev, "AST 2500 detected\n");
                        break;
                }
        } else if (pdev->revision >= 0x30) {
                switch (scu_rev & 0x300) {
                case 0x0100:
                        chip = AST1400;
                        dev_info(dev, "AST 1400 detected\n");
                        break;
                default:
                        chip = AST2400;
                        dev_info(dev, "AST 2400 detected\n");
                        break;
                }
        } else if (pdev->revision >= 0x20) {
                switch (scu_rev & 0x300) {
                case 0x0000:
                        chip = AST1300;
                        dev_info(dev, "AST 1300 detected\n");
                        break;
                default:
                        chip = AST2300;
                        dev_info(dev, "AST 2300 detected\n");
                        break;
                }
        } else if (pdev->revision >= 0x10) {
                switch (scu_rev & 0x0300) {
                case 0x0200:
                        chip = AST1100;
                        dev_info(dev, "AST 1100 detected\n");
                        break;
                case 0x0100:
                        chip = AST2200;
                        dev_info(dev, "AST 2200 detected\n");
                        break;
                case 0x0000:
                        chip = AST2150;
                        dev_info(dev, "AST 2150 detected\n");
                        break;
                default:
                        chip = AST2100;
                        dev_info(dev, "AST 2100 detected\n");
                        break;
                }
        } else {
                chip = AST2000;
                dev_info(dev, "AST 2000 detected\n");
        }

        *chip_out = chip;
        *config_mode_out = config_mode;

        return __AST_CHIP_GEN(chip);
}

static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        struct device *dev = &pdev->dev;
        int ret;
        void __iomem *regs;
        void __iomem *ioregs;
        enum ast_config_mode config_mode;
        enum ast_chip chip;
        unsigned int chip_gen;
        struct drm_device *drm;
        bool need_post = false;

        ret = aperture_remove_conflicting_pci_devices(pdev, ast_driver.name);
        if (ret)
                return ret;

        ret = pcim_enable_device(pdev);
        if (ret)
                return ret;

        regs = pcim_iomap_region(pdev, 1, "ast");
        if (IS_ERR(regs))
                return PTR_ERR(regs);

        if (pdev->revision >= 0x40) {
                /*
                 * On AST2500 and later models, MMIO is enabled by
                 * default. Adopt it to be compatible with ARM.
                 */
                resource_size_t len = pci_resource_len(pdev, 1);

                if (len < AST_IO_MM_OFFSET)
                        return -EIO;
                if ((len - AST_IO_MM_OFFSET) < AST_IO_MM_LENGTH)
                        return -EIO;
                ioregs = regs + AST_IO_MM_OFFSET;
        } else if (pci_resource_flags(pdev, 2) & IORESOURCE_IO) {
                /*
                 * Map I/O registers if we have a PCI BAR for I/O.
                 */
                resource_size_t len = pci_resource_len(pdev, 2);

                if (len < AST_IO_MM_LENGTH)
                        return -EIO;
                ioregs = pcim_iomap_region(pdev, 2, "ast");
                if (IS_ERR(ioregs))
                        return PTR_ERR(ioregs);
        } else {
                /*
                 * Anything else is best effort.
                 */
                resource_size_t len = pci_resource_len(pdev, 1);

                if (len < AST_IO_MM_OFFSET)
                        return -EIO;
                if ((len - AST_IO_MM_OFFSET) < AST_IO_MM_LENGTH)
                        return -EIO;
                ioregs = regs + AST_IO_MM_OFFSET;

                dev_info(dev, "Platform has no I/O space, using MMIO\n");
        }

        if (!ast_is_vga_enabled(ioregs)) {
                dev_info(dev, "VGA not enabled on entry, requesting chip POST\n");
                need_post = true;
        }

        /*
         * If VGA isn't enabled, we need to enable now or subsequent
         * access to the scratch registers will fail.
         */
        if (need_post)
                ast_enable_vga(ioregs);
        /* Enable extended register access */
        ast_open_key(ioregs);

        ret = ast_enable_mmio(dev, ioregs);
        if (ret)
                return ret;

        ret = ast_detect_chip(pdev, regs, ioregs, &chip, &config_mode);
        if (ret < 0)
                return ret;
        chip_gen = ret;

        switch (chip_gen) {
        case 1:
                drm = ast_2000_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 2:
                drm = ast_2100_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 3:
                drm = ast_2200_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 4:
                drm = ast_2300_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 5:
                drm = ast_2400_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 6:
                drm = ast_2500_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        case 7:
                drm = ast_2600_device_create(pdev, &ast_driver, chip, config_mode,
                                             regs, ioregs, need_post);
                break;
        default:
                dev_err(&pdev->dev, "Gen%d not supported\n", chip_gen);
                return -ENODEV;
        }
        if (IS_ERR(drm))
                return PTR_ERR(drm);
        pci_set_drvdata(pdev, drm);

        ret = drm_dev_register(drm, ent->driver_data);
        if (ret)
                return ret;

        drm_client_setup(drm, NULL);

        return 0;
}

static void ast_pci_remove(struct pci_dev *pdev)
{
        struct drm_device *dev = pci_get_drvdata(pdev);

        drm_dev_unregister(dev);
        drm_atomic_helper_shutdown(dev);
}

static void ast_pci_shutdown(struct pci_dev *pdev)
{
        drm_atomic_helper_shutdown(pci_get_drvdata(pdev));
}

static int ast_drm_freeze(struct drm_device *dev)
{
        int error;

        error = drm_mode_config_helper_suspend(dev);
        if (error)
                return error;
        pci_save_state(to_pci_dev(dev->dev));
        return 0;
}

static int ast_drm_thaw(struct drm_device *dev)
{
        struct ast_device *ast = to_ast_device(dev);
        int ret;

        ast_enable_vga(ast->ioregs);
        ast_open_key(ast->ioregs);
        ast_enable_mmio(dev->dev, ast->ioregs);

        ret = ast_post_gpu(ast);
        if (ret)
                return ret;

        return drm_mode_config_helper_resume(dev);
}

static int ast_drm_resume(struct drm_device *dev)
{
        if (pci_enable_device(to_pci_dev(dev->dev)))
                return -EIO;

        return ast_drm_thaw(dev);
}

static int ast_pm_suspend(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *ddev = pci_get_drvdata(pdev);
        int error;

        error = ast_drm_freeze(ddev);
        if (error)
                return error;

        pci_disable_device(pdev);
        pci_set_power_state(pdev, PCI_D3hot);
        return 0;
}

static int ast_pm_resume(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *ddev = pci_get_drvdata(pdev);
        return ast_drm_resume(ddev);
}

static int ast_pm_freeze(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *ddev = pci_get_drvdata(pdev);
        return ast_drm_freeze(ddev);
}

static int ast_pm_thaw(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *ddev = pci_get_drvdata(pdev);
        return ast_drm_thaw(ddev);
}

static int ast_pm_poweroff(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *ddev = pci_get_drvdata(pdev);

        return ast_drm_freeze(ddev);
}

static const struct dev_pm_ops ast_pm_ops = {
        .suspend = ast_pm_suspend,
        .resume = ast_pm_resume,
        .freeze = ast_pm_freeze,
        .thaw = ast_pm_thaw,
        .poweroff = ast_pm_poweroff,
        .restore = ast_pm_resume,
};

static struct pci_driver ast_pci_driver = {
        .name = DRIVER_NAME,
        .id_table = ast_pciidlist,
        .probe = ast_pci_probe,
        .remove = ast_pci_remove,
        .shutdown = ast_pci_shutdown,
        .driver.pm = &ast_pm_ops,
};

drm_module_pci_driver_if_modeset(ast_pci_driver, ast_modeset);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL and additional rights");