// SPDX-License-Identifier: GPL-2.0-only
/**************************************************************************
 * Copyright (c) 2007-2011, Intel Corporation.
 * All Rights Reserved.
 *
 **************************************************************************/

#include <linux/console.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/pfn_t.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/tty.h>

#include <drm/drm.h>
#include <drm/drm_crtc.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_framebuffer_helper.h>

#include "framebuffer.h"
#include "gtt.h"
#include "psb_drv.h"
#include "psb_intel_drv.h"
#include "psb_intel_reg.h"

static const struct drm_framebuffer_funcs psb_fb_funcs = {
        .destroy = drm_gem_fb_destroy,
        .create_handle = drm_gem_fb_create_handle,
};

#define CMAP_TOHW(_val, _width) ((((_val) << (_width)) + 0x7FFF - (_val)) >> 16)

static int psbfb_setcolreg(unsigned regno, unsigned red, unsigned green,
                           unsigned blue, unsigned transp,
                           struct fb_info *info)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct drm_framebuffer *fb = fb_helper->fb;
        uint32_t v;

        if (!fb)
                return -ENOMEM;

        if (regno > 255)
                return 1;

        red = CMAP_TOHW(red, info->var.red.length);
        blue = CMAP_TOHW(blue, info->var.blue.length);
        green = CMAP_TOHW(green, info->var.green.length);
        transp = CMAP_TOHW(transp, info->var.transp.length);

        v = (red << info->var.red.offset) |
            (green << info->var.green.offset) |
            (blue << info->var.blue.offset) |
            (transp << info->var.transp.offset);

        if (regno < 16) {
                switch (fb->format->cpp[0] * 8) {
                case 16:
                        ((uint32_t *) info->pseudo_palette)[regno] = v;
                        break;
                case 24:
                case 32:
                        ((uint32_t *) info->pseudo_palette)[regno] = v;
                        break;
                }
        }

        return 0;
}

static int psbfb_pan(struct fb_var_screeninfo *var, struct fb_info *info)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct drm_framebuffer *fb = fb_helper->fb;
        struct drm_device *dev = fb->dev;
        struct gtt_range *gtt = to_gtt_range(fb->obj[0]);

        /*
         *      We have to poke our nose in here. The core fb code assumes
         *      panning is part of the hardware that can be invoked before
         *      the actual fb is mapped. In our case that isn't quite true.
         */
        if (gtt->npage) {
                /* GTT roll shifts in 4K pages, we need to shift the right
                   number of pages */
                int pages = info->fix.line_length >> 12;
                psb_gtt_roll(dev, gtt, var->yoffset * pages);
        }
        return 0;
}

static vm_fault_t psbfb_vm_fault(struct vm_fault *vmf)
{
        struct vm_area_struct *vma = vmf->vma;
        struct drm_framebuffer *fb = vma->vm_private_data;
        struct drm_device *dev = fb->dev;
        struct drm_psb_private *dev_priv = dev->dev_private;
        struct gtt_range *gtt = to_gtt_range(fb->obj[0]);
        int page_num;
        int i;
        unsigned long address;
        vm_fault_t ret = VM_FAULT_SIGBUS;
        unsigned long pfn;
        unsigned long phys_addr = (unsigned long)dev_priv->stolen_base +
                                  gtt->offset;

        page_num = vma_pages(vma);
        address = vmf->address - (vmf->pgoff << PAGE_SHIFT);

        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

        for (i = 0; i < page_num; i++) {
                pfn = (phys_addr >> PAGE_SHIFT);

                ret = vmf_insert_mixed(vma, address,
                                __pfn_to_pfn_t(pfn, PFN_DEV));
                if (unlikely(ret & VM_FAULT_ERROR))
                        break;
                address += PAGE_SIZE;
                phys_addr += PAGE_SIZE;
        }
        return ret;
}

static void psbfb_vm_open(struct vm_area_struct *vma)
{
}

static void psbfb_vm_close(struct vm_area_struct *vma)
{
}

static const struct vm_operations_struct psbfb_vm_ops = {
        .fault  = psbfb_vm_fault,
        .open   = psbfb_vm_open,
        .close  = psbfb_vm_close
};

static int psbfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
        struct drm_fb_helper *fb_helper = info->par;
        struct drm_framebuffer *fb = fb_helper->fb;

        if (vma->vm_pgoff != 0)
                return -EINVAL;
        if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
                return -EINVAL;

        /*
         * If this is a GEM object then info->screen_base is the virtual
         * kernel remapping of the object. FIXME: Review if this is
         * suitable for our mmap work
         */
        vma->vm_ops = &psbfb_vm_ops;
        vma->vm_private_data = (void *)fb;
        vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
        return 0;
}

static const struct fb_ops psbfb_ops = {
        .owner = THIS_MODULE,
        DRM_FB_HELPER_DEFAULT_OPS,
        .fb_setcolreg = psbfb_setcolreg,
        .fb_fillrect = drm_fb_helper_cfb_fillrect,
        .fb_copyarea = psbfb_copyarea,
        .fb_imageblit = drm_fb_helper_cfb_imageblit,
        .fb_mmap = psbfb_mmap,
        .fb_sync = psbfb_sync,
};

static const struct fb_ops psbfb_roll_ops = {
        .owner = THIS_MODULE,
        DRM_FB_HELPER_DEFAULT_OPS,
        .fb_setcolreg = psbfb_setcolreg,
        .fb_fillrect = drm_fb_helper_cfb_fillrect,
        .fb_copyarea = drm_fb_helper_cfb_copyarea,
        .fb_imageblit = drm_fb_helper_cfb_imageblit,
        .fb_pan_display = psbfb_pan,
        .fb_mmap = psbfb_mmap,
};

static const struct fb_ops psbfb_unaccel_ops = {
        .owner = THIS_MODULE,
        DRM_FB_HELPER_DEFAULT_OPS,
        .fb_setcolreg = psbfb_setcolreg,
        .fb_fillrect = drm_fb_helper_cfb_fillrect,
        .fb_copyarea = drm_fb_helper_cfb_copyarea,
        .fb_imageblit = drm_fb_helper_cfb_imageblit,
        .fb_mmap = psbfb_mmap,
};

/**
 *      psb_framebuffer_init    -       initialize a framebuffer
 *      @dev: our DRM device
 *      @fb: framebuffer to set up
 *      @mode_cmd: mode description
 *      @gt: backing object
 *
 *      Configure and fill in the boilerplate for our frame buffer. Return
 *      0 on success or an error code if we fail.
 */
static int psb_framebuffer_init(struct drm_device *dev,
                                        struct drm_framebuffer *fb,
                                        const struct drm_mode_fb_cmd2 *mode_cmd,
                                        struct drm_gem_object *obj)
{
        const struct drm_format_info *info;
        int ret;

        /*
         * Reject unknown formats, YUV formats, and formats with more than
         * 4 bytes per pixel.
         */
        info = drm_get_format_info(dev, mode_cmd);
        if (!info || !info->depth || info->cpp[0] > 4)
                return -EINVAL;

        if (mode_cmd->pitches[0] & 63)
                return -EINVAL;

        drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
        fb->obj[0] = obj;
        ret = drm_framebuffer_init(dev, fb, &psb_fb_funcs);
        if (ret) {
                dev_err(dev->dev, "framebuffer init failed: %d\n", ret);
                return ret;
        }
        return 0;
}

/**
 *      psb_framebuffer_create  -       create a framebuffer backed by gt
 *      @dev: our DRM device
 *      @mode_cmd: the description of the requested mode
 *      @gt: the backing object
 *
 *      Create a framebuffer object backed by the gt, and fill in the
 *      boilerplate required
 *
 *      TODO: review object references
 */

static struct drm_framebuffer *psb_framebuffer_create
                        (struct drm_device *dev,
                         const struct drm_mode_fb_cmd2 *mode_cmd,
                         struct drm_gem_object *obj)
{
        struct drm_framebuffer *fb;
        int ret;

        fb = kzalloc(sizeof(*fb), GFP_KERNEL);
        if (!fb)
                return ERR_PTR(-ENOMEM);

        ret = psb_framebuffer_init(dev, fb, mode_cmd, obj);
        if (ret) {
                kfree(fb);
                return ERR_PTR(ret);
        }
        return fb;
}

/**
 *      psbfb_alloc             -       allocate frame buffer memory
 *      @dev: the DRM device
 *      @aligned_size: space needed
 *
 *      Allocate the frame buffer. In the usual case we get a GTT range that
 *      is stolen memory backed and life is simple. If there isn't sufficient
 *      we fail as we don't have the virtual mapping space to really vmap it
 *      and the kernel console code can't handle non linear framebuffers.
 *
 *      Re-address this as and if the framebuffer layer grows this ability.
 */
static struct gtt_range *psbfb_alloc(struct drm_device *dev, int aligned_size)
{
        struct gtt_range *backing;
        /* Begin by trying to use stolen memory backing */
        backing = psb_gtt_alloc_range(dev, aligned_size, "fb", 1, PAGE_SIZE);
        if (backing) {
                drm_gem_private_object_init(dev, &backing->gem, aligned_size);
                return backing;
        }
        return NULL;
}

/**
 *      psbfb_create            -       create a framebuffer
 *      @fbdev: the framebuffer device
 *      @sizes: specification of the layout
 *
 *      Create a framebuffer to the specifications provided
 */
static int psbfb_create(struct drm_fb_helper *fb_helper,
                                struct drm_fb_helper_surface_size *sizes)
{
        struct drm_device *dev = fb_helper->dev;
        struct drm_psb_private *dev_priv = dev->dev_private;
        struct fb_info *info;
        struct drm_framebuffer *fb;
        struct drm_mode_fb_cmd2 mode_cmd;
        int size;
        int ret;
        struct gtt_range *backing;
        u32 bpp, depth;
        int gtt_roll = 0;
        int pitch_lines = 0;

        mode_cmd.width = sizes->surface_width;
        mode_cmd.height = sizes->surface_height;
        bpp = sizes->surface_bpp;
        depth = sizes->surface_depth;

        /* No 24bit packed */
        if (bpp == 24)
                bpp = 32;

        do {
                /*
                 * Acceleration via the GTT requires pitch to be
                 * power of two aligned. Preferably page but less
                 * is ok with some fonts
                 */
                mode_cmd.pitches[0] =  ALIGN(mode_cmd.width * ((bpp + 7) / 8), 4096 >> pitch_lines);

                size = mode_cmd.pitches[0] * mode_cmd.height;
                size = ALIGN(size, PAGE_SIZE);

                /* Allocate the fb in the GTT with stolen page backing */
                backing = psbfb_alloc(dev, size);

                if (pitch_lines)
                        pitch_lines *= 2;
                else
                        pitch_lines = 1;
                gtt_roll++;
        } while (backing == NULL && pitch_lines <= 16);

        /* The final pitch we accepted if we succeeded */
        pitch_lines /= 2;

        if (backing == NULL) {
                /*
                 *      We couldn't get the space we wanted, fall back to the
                 *      display engine requirement instead.  The HW requires
                 *      the pitch to be 64 byte aligned
                 */

                gtt_roll = 0;   /* Don't use GTT accelerated scrolling */
                pitch_lines = 64;

                mode_cmd.pitches[0] =  ALIGN(mode_cmd.width * ((bpp + 7) / 8), 64);

                size = mode_cmd.pitches[0] * mode_cmd.height;
                size = ALIGN(size, PAGE_SIZE);

                /* Allocate the framebuffer in the GTT with stolen page backing */
                backing = psbfb_alloc(dev, size);
                if (backing == NULL)
                        return -ENOMEM;
        }

        memset(dev_priv->vram_addr + backing->offset, 0, size);

        info = drm_fb_helper_alloc_fbi(fb_helper);
        if (IS_ERR(info)) {
                ret = PTR_ERR(info);
                goto out;
        }

        mode_cmd.pixel_format = drm_mode_legacy_fb_format(bpp, depth);

        fb = psb_framebuffer_create(dev, &mode_cmd, &backing->gem);
        if (IS_ERR(fb)) {
                ret = PTR_ERR(fb);
                goto out;
        }

        fb_helper->fb = fb;

        if (dev_priv->ops->accel_2d && pitch_lines > 8) /* 2D engine */
                info->fbops = &psbfb_ops;
        else if (gtt_roll) {    /* GTT rolling seems best */
                info->fbops = &psbfb_roll_ops;
                info->flags |= FBINFO_HWACCEL_YPAN;
        } else  /* Software */
                info->fbops = &psbfb_unaccel_ops;

        info->fix.smem_start = dev->mode_config.fb_base;
        info->fix.smem_len = size;
        info->fix.ywrapstep = gtt_roll;
        info->fix.ypanstep = 0;

        /* Accessed stolen memory directly */
        info->screen_base = dev_priv->vram_addr + backing->offset;
        info->screen_size = size;

        if (dev_priv->gtt.stolen_size) {
                info->apertures->ranges[0].base = dev->mode_config.fb_base;
                info->apertures->ranges[0].size = dev_priv->gtt.stolen_size;
        }

        drm_fb_helper_fill_info(info, fb_helper, sizes);

        info->fix.mmio_start = pci_resource_start(dev->pdev, 0);
        info->fix.mmio_len = pci_resource_len(dev->pdev, 0);

        /* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */

        dev_dbg(dev->dev, "allocated %dx%d fb\n", fb->width, fb->height);

        return 0;
out:
        psb_gtt_free_range(dev, backing);
        return ret;
}

/**
 *      psb_user_framebuffer_create     -       create framebuffer
 *      @dev: our DRM device
 *      @filp: client file
 *      @cmd: mode request
 *
 *      Create a new framebuffer backed by a userspace GEM object
 */
static struct drm_framebuffer *psb_user_framebuffer_create
                        (struct drm_device *dev, struct drm_file *filp,
                         const struct drm_mode_fb_cmd2 *cmd)
{
        struct drm_gem_object *obj;

        /*
         *      Find the GEM object and thus the gtt range object that is
         *      to back this space
         */
        obj = drm_gem_object_lookup(filp, cmd->handles[0]);
        if (obj == NULL)
                return ERR_PTR(-ENOENT);

        /* Let the core code do all the work */
        return psb_framebuffer_create(dev, cmd, obj);
}

static int psbfb_probe(struct drm_fb_helper *fb_helper,
                                struct drm_fb_helper_surface_size *sizes)
{
        struct drm_device *dev = fb_helper->dev;
        struct drm_psb_private *dev_priv = dev->dev_private;
        unsigned int fb_size;
        int bytespp;

        bytespp = sizes->surface_bpp / 8;
        if (bytespp == 3)       /* no 24bit packed */
                bytespp = 4;

        /* If the mode will not fit in 32bit then switch to 16bit to get
           a console on full resolution. The X mode setting server will
           allocate its own 32bit GEM framebuffer */
        fb_size = ALIGN(sizes->surface_width * bytespp, 64) *
                  sizes->surface_height;
        fb_size = ALIGN(fb_size, PAGE_SIZE);

        if (fb_size > dev_priv->vram_stolen_size) {
                sizes->surface_bpp = 16;
                sizes->surface_depth = 16;
        }

        return psbfb_create(fb_helper, sizes);
}

static const struct drm_fb_helper_funcs psb_fb_helper_funcs = {
        .fb_probe = psbfb_probe,
};

static int psb_fbdev_destroy(struct drm_device *dev,
                             struct drm_fb_helper *fb_helper)
{
        struct drm_framebuffer *fb = fb_helper->fb;

        drm_fb_helper_unregister_fbi(fb_helper);

        drm_fb_helper_fini(fb_helper);
        drm_framebuffer_unregister_private(fb);
        drm_framebuffer_cleanup(fb);

        if (fb->obj[0])
                drm_gem_object_put(fb->obj[0]);
        kfree(fb);

        return 0;
}

int psb_fbdev_init(struct drm_device *dev)
{
        struct drm_fb_helper *fb_helper;
        struct drm_psb_private *dev_priv = dev->dev_private;
        int ret;

        fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);
        if (!fb_helper) {
                dev_err(dev->dev, "no memory\n");
                return -ENOMEM;
        }

        dev_priv->fb_helper = fb_helper;

        drm_fb_helper_prepare(dev, fb_helper, &psb_fb_helper_funcs);

        ret = drm_fb_helper_init(dev, fb_helper);
        if (ret)
                goto free;

        /* disable all the possible outputs/crtcs before entering KMS mode */
        drm_helper_disable_unused_functions(dev);

        ret = drm_fb_helper_initial_config(fb_helper, 32);
        if (ret)
                goto fini;

        return 0;

fini:
        drm_fb_helper_fini(fb_helper);
free:
        kfree(fb_helper);
        return ret;
}

static void psb_fbdev_fini(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;

        if (!dev_priv->fb_helper)
                return;

        psb_fbdev_destroy(dev, dev_priv->fb_helper);
        kfree(dev_priv->fb_helper);
        dev_priv->fb_helper = NULL;
}

static const struct drm_mode_config_funcs psb_mode_funcs = {
        .fb_create = psb_user_framebuffer_create,
        .output_poll_changed = drm_fb_helper_output_poll_changed,
};

static void psb_setup_outputs(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;
        struct drm_connector *connector;

        drm_mode_create_scaling_mode_property(dev);

        /* It is ok for this to fail - we just don't get backlight control */
        if (!dev_priv->backlight_property)
                dev_priv->backlight_property = drm_property_create_range(dev, 0,
                                                        "backlight", 0, 100);
        dev_priv->ops->output_init(dev);

        list_for_each_entry(connector, &dev->mode_config.connector_list,
                            head) {
                struct gma_encoder *gma_encoder = gma_attached_encoder(connector);
                struct drm_encoder *encoder = &gma_encoder->base;
                int crtc_mask = 0, clone_mask = 0;

                /* valid crtcs */
                switch (gma_encoder->type) {
                case INTEL_OUTPUT_ANALOG:
                        crtc_mask = (1 << 0);
                        clone_mask = (1 << INTEL_OUTPUT_ANALOG);
                        break;
                case INTEL_OUTPUT_SDVO:
                        crtc_mask = dev_priv->ops->sdvo_mask;
                        clone_mask = 0;
                        break;
                case INTEL_OUTPUT_LVDS:
                        crtc_mask = dev_priv->ops->lvds_mask;
                        clone_mask = 0;
                        break;
                case INTEL_OUTPUT_MIPI:
                        crtc_mask = (1 << 0);
                        clone_mask = 0;
                        break;
                case INTEL_OUTPUT_MIPI2:
                        crtc_mask = (1 << 2);
                        clone_mask = 0;
                        break;
                case INTEL_OUTPUT_HDMI:
                        crtc_mask = dev_priv->ops->hdmi_mask;
                        clone_mask = (1 << INTEL_OUTPUT_HDMI);
                        break;
                case INTEL_OUTPUT_DISPLAYPORT:
                        crtc_mask = (1 << 0) | (1 << 1);
                        clone_mask = 0;
                        break;
                case INTEL_OUTPUT_EDP:
                        crtc_mask = (1 << 1);
                        clone_mask = 0;
                }
                encoder->possible_crtcs = crtc_mask;
                encoder->possible_clones =
                    gma_connector_clones(dev, clone_mask);
        }
}

void psb_modeset_init(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;
        struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
        int i;

        drm_mode_config_init(dev);

        dev->mode_config.min_width = 0;
        dev->mode_config.min_height = 0;

        dev->mode_config.funcs = &psb_mode_funcs;

        /* set memory base */
        /* Oaktrail and Poulsbo should use BAR 2*/
        pci_read_config_dword(dev->pdev, PSB_BSM, (u32 *)
                                        &(dev->mode_config.fb_base));

        /* num pipes is 2 for PSB but 1 for Mrst */
        for (i = 0; i < dev_priv->num_pipe; i++)
                psb_intel_crtc_init(dev, i, mode_dev);

        dev->mode_config.max_width = 4096;
        dev->mode_config.max_height = 4096;

        psb_setup_outputs(dev);

        if (dev_priv->ops->errata)
                dev_priv->ops->errata(dev);

        dev_priv->modeset = true;
}

void psb_modeset_cleanup(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = dev->dev_private;
        if (dev_priv->modeset) {
                drm_kms_helper_poll_fini(dev);
                psb_fbdev_fini(dev);
                drm_mode_config_cleanup(dev);
        }
}