/* sunxvr500.c: Sun 3DLABS XVR-500 Expert3D fb driver for sparc64 systems
 *
 * License: GPL
 *
 * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
 */

#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/of_device.h>

#include <asm/io.h>

/* XXX This device has a 'dev-comm' property which apparently is
 * XXX a pointer into the openfirmware's address space which is
 * XXX a shared area the kernel driver can use to keep OBP
 * XXX informed about the current resolution setting.  The idea
 * XXX is that the kernel can change resolutions, and as long
 * XXX as the values in the 'dev-comm' area are accurate then
 * XXX OBP can still render text properly to the console.
 * XXX
 * XXX I'm still working out the layout of this and whether there
 * XXX are any signatures we need to look for etc.
 */
struct e3d_info {
        struct fb_info          *info;
        struct pci_dev          *pdev;

        spinlock_t              lock;

        char __iomem            *fb_base;
        unsigned long           fb_base_phys;

        unsigned long           fb8_buf_diff;
        unsigned long           regs_base_phys;

        void __iomem            *ramdac;

        struct device_node      *of_node;

        unsigned int            width;
        unsigned int            height;
        unsigned int            depth;
        unsigned int            fb_size;

        u32                     fb_base_reg;
        u32                     fb8_0_off;
        u32                     fb8_1_off;

        u32                     pseudo_palette[16];
};

static int e3d_get_props(struct e3d_info *ep)
{
        ep->width = of_getintprop_default(ep->of_node, "width", 0);
        ep->height = of_getintprop_default(ep->of_node, "height", 0);
        ep->depth = of_getintprop_default(ep->of_node, "depth", 8);

        if (!ep->width || !ep->height) {
                printk(KERN_ERR "e3d: Critical properties missing for %s\n",
                       pci_name(ep->pdev));
                return -EINVAL;
        }

        return 0;
}

/* My XVR-500 comes up, at 1280x768 and a FB base register value of
 * 0x04000000, the following video layout register values:
 *
 * RAMDAC_VID_WH        0x03ff04ff
 * RAMDAC_VID_CFG       0x1a0b0088
 * RAMDAC_VID_32FB_0    0x04000000
 * RAMDAC_VID_32FB_1    0x04800000
 * RAMDAC_VID_8FB_0     0x05000000
 * RAMDAC_VID_8FB_1     0x05200000
 * RAMDAC_VID_XXXFB     0x05400000
 * RAMDAC_VID_YYYFB     0x05c00000
 * RAMDAC_VID_ZZZFB     0x05e00000
 */
/* Video layout registers */
#define RAMDAC_VID_WH           0x00000070UL /* (height-1)<<16 | (width-1) */
#define RAMDAC_VID_CFG          0x00000074UL /* 0x1a000088|(linesz_log2<<16) */
#define RAMDAC_VID_32FB_0       0x00000078UL /* PCI base 32bpp FB buffer 0 */
#define RAMDAC_VID_32FB_1       0x0000007cUL /* PCI base 32bpp FB buffer 1 */
#define RAMDAC_VID_8FB_0        0x00000080UL /* PCI base 8bpp FB buffer 0 */
#define RAMDAC_VID_8FB_1        0x00000084UL /* PCI base 8bpp FB buffer 1 */
#define RAMDAC_VID_XXXFB        0x00000088UL /* PCI base of XXX FB */
#define RAMDAC_VID_YYYFB        0x0000008cUL /* PCI base of YYY FB */
#define RAMDAC_VID_ZZZFB        0x00000090UL /* PCI base of ZZZ FB */

/* CLUT registers */
#define RAMDAC_INDEX            0x000000bcUL
#define RAMDAC_DATA             0x000000c0UL

static void e3d_clut_write(struct e3d_info *ep, int index, u32 val)
{
        void __iomem *ramdac = ep->ramdac;
        unsigned long flags;

        spin_lock_irqsave(&ep->lock, flags);

        writel(index, ramdac + RAMDAC_INDEX);
        writel(val, ramdac + RAMDAC_DATA);

        spin_unlock_irqrestore(&ep->lock, flags);
}

static int e3d_setcolreg(unsigned regno,
                         unsigned red, unsigned green, unsigned blue,
                         unsigned transp, struct fb_info *info)
{
        struct e3d_info *ep = info->par;
        u32 red_8, green_8, blue_8;
        u32 red_10, green_10, blue_10;
        u32 value;

        if (regno >= 256)
                return 1;

        red_8 = red >> 8;
        green_8 = green >> 8;
        blue_8 = blue >> 8;

        value = (blue_8 << 24) | (green_8 << 16) | (red_8 << 8);

        if (info->fix.visual == FB_VISUAL_TRUECOLOR && regno < 16)
                ((u32 *)info->pseudo_palette)[regno] = value;


        red_10 = red >> 6;
        green_10 = green >> 6;
        blue_10 = blue >> 6;

        value = (blue_10 << 20) | (green_10 << 10) | (red_10 << 0);
        e3d_clut_write(ep, regno, value);

        return 0;
}

/* XXX This is a bit of a hack.  I can't figure out exactly how the
 * XXX two 8bpp areas of the framebuffer work.  I imagine there is
 * XXX a WID attribute somewhere else in the framebuffer which tells
 * XXX the ramdac which of the two 8bpp framebuffer regions to take
 * XXX the pixel from.  So, for now, render into both regions to make
 * XXX sure the pixel shows up.
 */
static void e3d_imageblit(struct fb_info *info, const struct fb_image *image)
{
        struct e3d_info *ep = info->par;
        unsigned long flags;

        spin_lock_irqsave(&ep->lock, flags);
        cfb_imageblit(info, image);
        info->screen_base += ep->fb8_buf_diff;
        cfb_imageblit(info, image);
        info->screen_base -= ep->fb8_buf_diff;
        spin_unlock_irqrestore(&ep->lock, flags);
}

static void e3d_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
        struct e3d_info *ep = info->par;
        unsigned long flags;

        spin_lock_irqsave(&ep->lock, flags);
        cfb_fillrect(info, rect);
        info->screen_base += ep->fb8_buf_diff;
        cfb_fillrect(info, rect);
        info->screen_base -= ep->fb8_buf_diff;
        spin_unlock_irqrestore(&ep->lock, flags);
}

static void e3d_copyarea(struct fb_info *info, const struct fb_copyarea *area)
{
        struct e3d_info *ep = info->par;
        unsigned long flags;

        spin_lock_irqsave(&ep->lock, flags);
        cfb_copyarea(info, area);
        info->screen_base += ep->fb8_buf_diff;
        cfb_copyarea(info, area);
        info->screen_base -= ep->fb8_buf_diff;
        spin_unlock_irqrestore(&ep->lock, flags);
}

static const struct fb_ops e3d_ops = {
        .owner                  = THIS_MODULE,
        .fb_setcolreg           = e3d_setcolreg,
        .fb_fillrect            = e3d_fillrect,
        .fb_copyarea            = e3d_copyarea,
        .fb_imageblit           = e3d_imageblit,
};

static int e3d_set_fbinfo(struct e3d_info *ep)
{
        struct fb_info *info = ep->info;
        struct fb_var_screeninfo *var = &info->var;

        info->flags = FBINFO_DEFAULT;
        info->fbops = &e3d_ops;
        info->screen_base = ep->fb_base;
        info->screen_size = ep->fb_size;

        info->pseudo_palette = ep->pseudo_palette;

        /* Fill fix common fields */
        strlcpy(info->fix.id, "e3d", sizeof(info->fix.id));
        info->fix.smem_start = ep->fb_base_phys;
        info->fix.smem_len = ep->fb_size;
        info->fix.type = FB_TYPE_PACKED_PIXELS;
        if (ep->depth == 32 || ep->depth == 24)
                info->fix.visual = FB_VISUAL_TRUECOLOR;
        else
                info->fix.visual = FB_VISUAL_PSEUDOCOLOR;

        var->xres = ep->width;
        var->yres = ep->height;
        var->xres_virtual = var->xres;
        var->yres_virtual = var->yres;
        var->bits_per_pixel = ep->depth;

        var->red.offset = 8;
        var->red.length = 8;
        var->green.offset = 16;
        var->green.length = 8;
        var->blue.offset = 24;
        var->blue.length = 8;
        var->transp.offset = 0;
        var->transp.length = 0;

        if (fb_alloc_cmap(&info->cmap, 256, 0)) {
                printk(KERN_ERR "e3d: Cannot allocate color map.\n");
                return -ENOMEM;
        }

        return 0;
}

static int e3d_pci_register(struct pci_dev *pdev,
                            const struct pci_device_id *ent)
{
        struct device_node *of_node;
        const char *device_type;
        struct fb_info *info;
        struct e3d_info *ep;
        unsigned int line_length;
        int err;

        of_node = pci_device_to_OF_node(pdev);
        if (!of_node) {
                printk(KERN_ERR "e3d: Cannot find OF node of %s\n",
                       pci_name(pdev));
                return -ENODEV;
        }

        device_type = of_get_property(of_node, "device_type", NULL);
        if (!device_type) {
                printk(KERN_INFO "e3d: Ignoring secondary output device "
                       "at %s\n", pci_name(pdev));
                return -ENODEV;
        }

        err = pci_enable_device(pdev);
        if (err < 0) {
                printk(KERN_ERR "e3d: Cannot enable PCI device %s\n",
                       pci_name(pdev));
                goto err_out;
        }

        info = framebuffer_alloc(sizeof(struct e3d_info), &pdev->dev);
        if (!info) {
                err = -ENOMEM;
                goto err_disable;
        }

        ep = info->par;
        ep->info = info;
        ep->pdev = pdev;
        spin_lock_init(&ep->lock);
        ep->of_node = of_node;

        /* Read the PCI base register of the frame buffer, which we
         * need in order to interpret the RAMDAC_VID_*FB* values in
         * the ramdac correctly.
         */
        pci_read_config_dword(pdev, PCI_BASE_ADDRESS_0,
                              &ep->fb_base_reg);
        ep->fb_base_reg &= PCI_BASE_ADDRESS_MEM_MASK;

        ep->regs_base_phys = pci_resource_start (pdev, 1);
        err = pci_request_region(pdev, 1, "e3d regs");
        if (err < 0) {
                printk("e3d: Cannot request region 1 for %s\n",
                       pci_name(pdev));
                goto err_release_fb;
        }
        ep->ramdac = ioremap(ep->regs_base_phys + 0x8000, 0x1000);
        if (!ep->ramdac) {
                err = -ENOMEM;
                goto err_release_pci1;
        }

        ep->fb8_0_off = readl(ep->ramdac + RAMDAC_VID_8FB_0);
        ep->fb8_0_off -= ep->fb_base_reg;

        ep->fb8_1_off = readl(ep->ramdac + RAMDAC_VID_8FB_1);
        ep->fb8_1_off -= ep->fb_base_reg;

        ep->fb8_buf_diff = ep->fb8_1_off - ep->fb8_0_off;

        ep->fb_base_phys = pci_resource_start (pdev, 0);
        ep->fb_base_phys += ep->fb8_0_off;

        err = pci_request_region(pdev, 0, "e3d framebuffer");
        if (err < 0) {
                printk("e3d: Cannot request region 0 for %s\n",
                       pci_name(pdev));
                goto err_unmap_ramdac;
        }

        err = e3d_get_props(ep);
        if (err)
                goto err_release_pci0;

        line_length = (readl(ep->ramdac + RAMDAC_VID_CFG) >> 16) & 0xff;
        line_length = 1 << line_length;

        switch (ep->depth) {
        case 8:
                info->fix.line_length = line_length;
                break;
        case 16:
                info->fix.line_length = line_length * 2;
                break;
        case 24:
                info->fix.line_length = line_length * 3;
                break;
        case 32:
                info->fix.line_length = line_length * 4;
                break;
        }
        ep->fb_size = info->fix.line_length * ep->height;

        ep->fb_base = ioremap(ep->fb_base_phys, ep->fb_size);
        if (!ep->fb_base) {
                err = -ENOMEM;
                goto err_release_pci0;
        }

        err = e3d_set_fbinfo(ep);
        if (err)
                goto err_unmap_fb;

        pci_set_drvdata(pdev, info);

        printk("e3d: Found device at %s\n", pci_name(pdev));

        err = register_framebuffer(info);
        if (err < 0) {
                printk(KERN_ERR "e3d: Could not register framebuffer %s\n",
                       pci_name(pdev));
                goto err_free_cmap;
        }

        return 0;

err_free_cmap:
        fb_dealloc_cmap(&info->cmap);

err_unmap_fb:
        iounmap(ep->fb_base);

err_release_pci0:
        pci_release_region(pdev, 0);

err_unmap_ramdac:
        iounmap(ep->ramdac);

err_release_pci1:
        pci_release_region(pdev, 1);

err_release_fb:
        framebuffer_release(info);

err_disable:
        pci_disable_device(pdev);

err_out:
        return err;
}

static const struct pci_device_id e3d_pci_table[] = {
        {       PCI_DEVICE(PCI_VENDOR_ID_3DLABS, 0x7a0),        },
        {       PCI_DEVICE(0x1091, 0x7a0),                      },
        {       PCI_DEVICE(PCI_VENDOR_ID_3DLABS, 0x7a2),        },
        {       .vendor = PCI_VENDOR_ID_3DLABS,
                .device = PCI_ANY_ID,
                .subvendor = PCI_VENDOR_ID_3DLABS,
                .subdevice = 0x0108,
        },
        {       .vendor = PCI_VENDOR_ID_3DLABS,
                .device = PCI_ANY_ID,
                .subvendor = PCI_VENDOR_ID_3DLABS,
                .subdevice = 0x0140,
        },
        {       .vendor = PCI_VENDOR_ID_3DLABS,
                .device = PCI_ANY_ID,
                .subvendor = PCI_VENDOR_ID_3DLABS,
                .subdevice = 0x1024,
        },
        { 0, }
};

static struct pci_driver e3d_driver = {
        .driver = {
                .suppress_bind_attrs = true,
        },
        .name           = "e3d",
        .id_table       = e3d_pci_table,
        .probe          = e3d_pci_register,
};

static int __init e3d_init(void)
{
        if (fb_get_options("e3d", NULL))
                return -ENODEV;

        return pci_register_driver(&e3d_driver);
}
device_initcall(e3d_init);