// SPDX-License-Identifier: MIT
/*
 * Copyright © 2021-2024 Intel Corporation
 */

#include <kunit/visibility.h>
#include <linux/pci.h>

#include <drm/drm_managed.h>
#include <drm/drm_print.h>

#include "regs/xe_bars.h"
#include "regs/xe_gt_regs.h"
#include "regs/xe_regs.h"
#include "xe_assert.h"
#include "xe_device.h"
#include "xe_force_wake.h"
#include "xe_gt_mcr.h"
#include "xe_mmio.h"
#include "xe_sriov.h"
#include "xe_tile_sriov_vf.h"
#include "xe_ttm_vram_mgr.h"
#include "xe_vram.h"
#include "xe_vram_types.h"

static bool resource_is_valid(struct pci_dev *pdev, int bar)
{
        if (!pci_resource_flags(pdev, bar))
                return false;

        if (pci_resource_flags(pdev, bar) & IORESOURCE_UNSET)
                return false;

        if (!pci_resource_len(pdev, bar))
                return false;

        return true;
}

static int determine_lmem_bar_size(struct xe_device *xe, struct xe_vram_region *lmem_bar)
{
        struct pci_dev *pdev = to_pci_dev(xe->drm.dev);

        if (!resource_is_valid(pdev, LMEM_BAR)) {
                drm_err(&xe->drm, "pci resource is not valid\n");
                return -ENXIO;
        }

        lmem_bar->io_start = pci_resource_start(pdev, LMEM_BAR);
        lmem_bar->io_size = pci_resource_len(pdev, LMEM_BAR);
        if (!lmem_bar->io_size)
                return -EIO;

        /* XXX: Need to change when xe link code is ready */
        lmem_bar->dpa_base = 0;

        /* set up a map to the total memory area. */
        lmem_bar->mapping = devm_ioremap_wc(&pdev->dev, lmem_bar->io_start, lmem_bar->io_size);

        return 0;
}

static int get_flat_ccs_offset(struct xe_gt *gt, u64 tile_size, u64 *poffset)
{
        struct xe_device *xe = gt_to_xe(gt);
        u64 offset;
        u32 reg;

        CLASS(xe_force_wake, fw_ref)(gt_to_fw(gt), XE_FW_GT);
        if (!fw_ref.domains)
                return -ETIMEDOUT;

        if (GRAPHICS_VER(xe) >= 20) {
                u64 ccs_size = tile_size / 512;
                u64 offset_hi, offset_lo;
                u32 nodes, num_enabled;

                reg = xe_mmio_read32(&gt->mmio, MIRROR_FUSE3);
                nodes = REG_FIELD_GET(XE2_NODE_ENABLE_MASK, reg);
                num_enabled = hweight32(nodes); /* Number of enabled l3 nodes */

                reg = xe_gt_mcr_unicast_read_any(gt, XE2_FLAT_CCS_BASE_RANGE_LOWER);
                offset_lo = REG_FIELD_GET(XE2_FLAT_CCS_BASE_LOWER_ADDR_MASK, reg);

                reg = xe_gt_mcr_unicast_read_any(gt, XE2_FLAT_CCS_BASE_RANGE_UPPER);
                offset_hi = REG_FIELD_GET(XE2_FLAT_CCS_BASE_UPPER_ADDR_MASK, reg);

                offset = offset_hi << 32; /* HW view bits 39:32 */
                offset |= offset_lo << 6; /* HW view bits 31:6 */
                offset *= num_enabled; /* convert to SW view */
                offset = round_up(offset, SZ_128K); /* SW must round up to nearest 128K */

                /* We don't expect any holes */
                xe_assert_msg(xe, offset == (xe_mmio_read64_2x32(&gt_to_tile(gt)->mmio, GSMBASE) -
                                             ccs_size),
                              "Hole between CCS and GSM.\n");
        } else {
                reg = xe_gt_mcr_unicast_read_any(gt, XEHP_FLAT_CCS_BASE_ADDR);
                offset = (u64)REG_FIELD_GET(XEHP_FLAT_CCS_PTR, reg) * SZ_64K;
        }

        *poffset = offset;

        return 0;
}

/*
 * tile_vram_size() - Collect vram size and offset information
 * @tile: tile to get info for
 * @vram_size: available vram (size - device reserved portions)
 * @tile_size: actual vram size
 * @tile_offset: physical start point in the vram address space
 *
 * There are 4 places for size information:
 * - io size (from pci_resource_len of LMEM bar) (only used for small bar and DG1)
 * - TILEx size (actual vram size)
 * - GSMBASE offset (TILEx - "stolen")
 * - CSSBASE offset (TILEx - CSS space necessary)
 *
 * CSSBASE is always a lower/smaller offset then GSMBASE.
 *
 * The actual available size of memory is to the CCS or GSM base.
 * NOTE: multi-tile bases will include the tile offset.
 *
 */
static int tile_vram_size(struct xe_tile *tile, u64 *vram_size,
                          u64 *tile_size, u64 *tile_offset)
{
        struct xe_device *xe = tile_to_xe(tile);
        struct xe_gt *gt = tile->primary_gt;
        u64 offset;
        u32 reg;

        if (IS_SRIOV_VF(xe)) {
                struct xe_tile *t;
                int id;

                offset = 0;
                for_each_tile(t, xe, id)
                        for_each_if(t->id < tile->id)
                                offset += xe_tile_sriov_vf_lmem(t);

                *tile_size = xe_tile_sriov_vf_lmem(tile);
                *vram_size = *tile_size;
                *tile_offset = offset;

                return 0;
        }

        /* actual size */
        if (unlikely(xe->info.platform == XE_DG1)) {
                *tile_size = pci_resource_len(to_pci_dev(xe->drm.dev), LMEM_BAR);
                *tile_offset = 0;
        } else {
                reg = xe_mmio_read32(&tile->mmio, SG_TILE_ADDR_RANGE(tile->id));
                *tile_size = (u64)REG_FIELD_GET(GENMASK(17, 8), reg) * SZ_1G;
                *tile_offset = (u64)REG_FIELD_GET(GENMASK(7, 1), reg) * SZ_1G;
        }

        /* minus device usage */
        if (xe->info.has_flat_ccs) {
                int ret = get_flat_ccs_offset(gt, *tile_size, &offset);

                if (ret)
                        return ret;
        } else {
                offset = xe_mmio_read64_2x32(&tile->mmio, GSMBASE);
        }

        /* remove the tile offset so we have just the available size */
        *vram_size = offset - *tile_offset;

        return 0;
}

static void vram_fini(void *arg)
{
        struct xe_device *xe = arg;
        struct xe_tile *tile;
        int id;

        xe->mem.vram->mapping = NULL;

        for_each_tile(tile, xe, id) {
                tile->mem.vram->mapping = NULL;
                if (tile->mem.kernel_vram)
                        tile->mem.kernel_vram->mapping = NULL;
        }
}

struct xe_vram_region *xe_vram_region_alloc(struct xe_device *xe, u8 id, u32 placement)
{
        struct xe_vram_region *vram;
        struct drm_device *drm = &xe->drm;

        xe_assert(xe, id < xe->info.tile_count);

        vram = drmm_kzalloc(drm, sizeof(*vram), GFP_KERNEL);
        if (!vram)
                return NULL;

        vram->xe = xe;
        vram->id = id;
        vram->placement = placement;
#if defined(CONFIG_DRM_XE_PAGEMAP)
        vram->migrate = xe->tiles[id].migrate;
#endif
        return vram;
}

static void print_vram_region_info(struct xe_device *xe, struct xe_vram_region *vram)
{
        struct drm_device *drm = &xe->drm;

        if (vram->io_size < vram->usable_size)
                drm_info(drm, "Small BAR device\n");

        drm_info(drm,
                 "VRAM[%u]: Actual physical size %pa, usable size exclude stolen %pa, CPU accessible size %pa\n",
                 vram->id, &vram->actual_physical_size, &vram->usable_size, &vram->io_size);
        drm_info(drm, "VRAM[%u]: DPA range: [%pa-%llx], io range: [%pa-%llx]\n",
                 vram->id, &vram->dpa_base, vram->dpa_base + (u64)vram->actual_physical_size,
                 &vram->io_start, vram->io_start + (u64)vram->io_size);
}

static int vram_region_init(struct xe_device *xe, struct xe_vram_region *vram,
                            struct xe_vram_region *lmem_bar, u64 offset, u64 usable_size,
                            u64 region_size, resource_size_t remain_io_size)
{
        /* Check if VRAM region is already initialized */
        if (vram->mapping)
                return 0;

        vram->actual_physical_size = region_size;
        vram->io_start = lmem_bar->io_start + offset;
        vram->io_size = min_t(u64, usable_size, remain_io_size);

        if (!vram->io_size) {
                drm_err(&xe->drm, "Tile without any CPU visible VRAM. Aborting.\n");
                return -ENODEV;
        }

        vram->dpa_base = lmem_bar->dpa_base + offset;
        vram->mapping = lmem_bar->mapping + offset;
        vram->usable_size = usable_size;

        print_vram_region_info(xe, vram);

        return 0;
}

/**
 * xe_vram_probe() - Probe VRAM configuration
 * @xe: the &xe_device
 *
 * Collect VRAM size and offset information for all tiles.
 *
 * Return: 0 on success, error code on failure
 */
int xe_vram_probe(struct xe_device *xe)
{
        struct xe_tile *tile;
        struct xe_vram_region lmem_bar;
        resource_size_t remain_io_size;
        u64 available_size = 0;
        u64 total_size = 0;
        int err;
        u8 id;

        if (!IS_DGFX(xe))
                return 0;

        err = determine_lmem_bar_size(xe, &lmem_bar);
        if (err)
                return err;
        drm_info(&xe->drm, "VISIBLE VRAM: %pa, %pa\n", &lmem_bar.io_start, &lmem_bar.io_size);

        remain_io_size = lmem_bar.io_size;

        for_each_tile(tile, xe, id) {
                u64 region_size;
                u64 usable_size;
                u64 tile_offset;

                err = tile_vram_size(tile, &usable_size, &region_size, &tile_offset);
                if (err)
                        return err;

                total_size += region_size;
                available_size += usable_size;

                err = vram_region_init(xe, tile->mem.vram, &lmem_bar, tile_offset, usable_size,
                                       region_size, remain_io_size);
                if (err)
                        return err;

                if (total_size > lmem_bar.io_size) {
                        drm_info(&xe->drm, "VRAM: %pa is larger than resource %pa\n",
                                 &total_size, &lmem_bar.io_size);
                }

                remain_io_size -= min_t(u64, tile->mem.vram->actual_physical_size, remain_io_size);
        }

        err = vram_region_init(xe, xe->mem.vram, &lmem_bar, 0, available_size, total_size,
                               lmem_bar.io_size);
        if (err)
                return err;

        return devm_add_action_or_reset(xe->drm.dev, vram_fini, xe);
}

/**
 * xe_vram_region_io_start - Get the IO start of a VRAM region
 * @vram: the VRAM region
 *
 * Return: the IO start of the VRAM region, or 0 if not valid
 */
resource_size_t xe_vram_region_io_start(const struct xe_vram_region *vram)
{
        return vram ? vram->io_start : 0;
}

/**
 * xe_vram_region_io_size - Get the IO size of a VRAM region
 * @vram: the VRAM region
 *
 * Return: the IO size of the VRAM region, or 0 if not valid
 */
resource_size_t xe_vram_region_io_size(const struct xe_vram_region *vram)
{
        return vram ? vram->io_size : 0;
}

/**
 * xe_vram_region_dpa_base - Get the DPA base of a VRAM region
 * @vram: the VRAM region
 *
 * Return: the DPA base of the VRAM region, or 0 if not valid
 */
resource_size_t xe_vram_region_dpa_base(const struct xe_vram_region *vram)
{
        return vram ? vram->dpa_base : 0;
}

/**
 * xe_vram_region_usable_size - Get the usable size of a VRAM region
 * @vram: the VRAM region
 *
 * Return: the usable size of the VRAM region, or 0 if not valid
 */
resource_size_t xe_vram_region_usable_size(const struct xe_vram_region *vram)
{
        return vram ? vram->usable_size : 0;
}

/**
 * xe_vram_region_actual_physical_size - Get the actual physical size of a VRAM region
 * @vram: the VRAM region
 *
 * Return: the actual physical size of the VRAM region, or 0 if not valid
 */
resource_size_t xe_vram_region_actual_physical_size(const struct xe_vram_region *vram)
{
        return vram ? vram->actual_physical_size : 0;
}
EXPORT_SYMBOL_IF_KUNIT(xe_vram_region_actual_physical_size);