/*
 * Copyright 2016 Advanced Micro Devices, 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, 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
 *
 */

#include <linux/module.h>

#include <drm/drm_drv.h>

#include "amdgpu.h"

bool amdgpu_virt_mmio_blocked(struct amdgpu_device *adev)
{
        /* By now all MMIO pages except mailbox are blocked */
        /* if blocking is enabled in hypervisor. Choose the */
        /* SCRATCH_REG0 to test. */
        return RREG32_NO_KIQ(0xc040) == 0xffffffff;
}

void amdgpu_virt_init_setting(struct amdgpu_device *adev)
{
        /* enable virtual display */
        adev->mode_info.num_crtc = 1;
        adev->enable_virtual_display = true;
        adev->ddev->driver->driver_features &= ~DRIVER_ATOMIC;
        adev->cg_flags = 0;
        adev->pg_flags = 0;
}

void amdgpu_virt_kiq_reg_write_reg_wait(struct amdgpu_device *adev,
                                        uint32_t reg0, uint32_t reg1,
                                        uint32_t ref, uint32_t mask)
{
        struct amdgpu_kiq *kiq = &adev->gfx.kiq;
        struct amdgpu_ring *ring = &kiq->ring;
        signed long r, cnt = 0;
        unsigned long flags;
        uint32_t seq;

        spin_lock_irqsave(&kiq->ring_lock, flags);
        amdgpu_ring_alloc(ring, 32);
        amdgpu_ring_emit_reg_write_reg_wait(ring, reg0, reg1,
                                            ref, mask);
        amdgpu_fence_emit_polling(ring, &seq);
        amdgpu_ring_commit(ring);
        spin_unlock_irqrestore(&kiq->ring_lock, flags);

        r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);

        /* don't wait anymore for IRQ context */
        if (r < 1 && in_interrupt())
                goto failed_kiq;

        might_sleep();
        while (r < 1 && cnt++ < MAX_KIQ_REG_TRY) {

                msleep(MAX_KIQ_REG_BAILOUT_INTERVAL);
                r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
        }

        if (cnt > MAX_KIQ_REG_TRY)
                goto failed_kiq;

        return;

failed_kiq:
        pr_err("failed to write reg %x wait reg %x\n", reg0, reg1);
}

/**
 * amdgpu_virt_request_full_gpu() - request full gpu access
 * @amdgpu:     amdgpu device.
 * @init:       is driver init time.
 * When start to init/fini driver, first need to request full gpu access.
 * Return: Zero if request success, otherwise will return error.
 */
int amdgpu_virt_request_full_gpu(struct amdgpu_device *adev, bool init)
{
        struct amdgpu_virt *virt = &adev->virt;
        int r;

        if (virt->ops && virt->ops->req_full_gpu) {
                r = virt->ops->req_full_gpu(adev, init);
                if (r)
                        return r;

                adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
        }

        return 0;
}

/**
 * amdgpu_virt_release_full_gpu() - release full gpu access
 * @amdgpu:     amdgpu device.
 * @init:       is driver init time.
 * When finishing driver init/fini, need to release full gpu access.
 * Return: Zero if release success, otherwise will returen error.
 */
int amdgpu_virt_release_full_gpu(struct amdgpu_device *adev, bool init)
{
        struct amdgpu_virt *virt = &adev->virt;
        int r;

        if (virt->ops && virt->ops->rel_full_gpu) {
                r = virt->ops->rel_full_gpu(adev, init);
                if (r)
                        return r;

                adev->virt.caps |= AMDGPU_SRIOV_CAPS_RUNTIME;
        }
        return 0;
}

/**
 * amdgpu_virt_reset_gpu() - reset gpu
 * @amdgpu:     amdgpu device.
 * Send reset command to GPU hypervisor to reset GPU that VM is using
 * Return: Zero if reset success, otherwise will return error.
 */
int amdgpu_virt_reset_gpu(struct amdgpu_device *adev)
{
        struct amdgpu_virt *virt = &adev->virt;
        int r;

        if (virt->ops && virt->ops->reset_gpu) {
                r = virt->ops->reset_gpu(adev);
                if (r)
                        return r;

                adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
        }

        return 0;
}

/**
 * amdgpu_virt_wait_reset() - wait for reset gpu completed
 * @amdgpu:     amdgpu device.
 * Wait for GPU reset completed.
 * Return: Zero if reset success, otherwise will return error.
 */
int amdgpu_virt_wait_reset(struct amdgpu_device *adev)
{
        struct amdgpu_virt *virt = &adev->virt;

        if (!virt->ops || !virt->ops->wait_reset)
                return -EINVAL;

        return virt->ops->wait_reset(adev);
}

/**
 * amdgpu_virt_alloc_mm_table() - alloc memory for mm table
 * @amdgpu:     amdgpu device.
 * MM table is used by UVD and VCE for its initialization
 * Return: Zero if allocate success.
 */
int amdgpu_virt_alloc_mm_table(struct amdgpu_device *adev)
{
        int r;

        if (!amdgpu_sriov_vf(adev) || adev->virt.mm_table.gpu_addr)
                return 0;

        r = amdgpu_bo_create_kernel(adev, PAGE_SIZE, PAGE_SIZE,
                                    AMDGPU_GEM_DOMAIN_VRAM,
                                    &adev->virt.mm_table.bo,
                                    &adev->virt.mm_table.gpu_addr,
                                    (void *)&adev->virt.mm_table.cpu_addr);
        if (r) {
                DRM_ERROR("failed to alloc mm table and error = %d.\n", r);
                return r;
        }

        memset((void *)adev->virt.mm_table.cpu_addr, 0, PAGE_SIZE);
        DRM_INFO("MM table gpu addr = 0x%llx, cpu addr = %p.\n",
                 adev->virt.mm_table.gpu_addr,
                 adev->virt.mm_table.cpu_addr);
        return 0;
}

/**
 * amdgpu_virt_free_mm_table() - free mm table memory
 * @amdgpu:     amdgpu device.
 * Free MM table memory
 */
void amdgpu_virt_free_mm_table(struct amdgpu_device *adev)
{
        if (!amdgpu_sriov_vf(adev) || !adev->virt.mm_table.gpu_addr)
                return;

        amdgpu_bo_free_kernel(&adev->virt.mm_table.bo,
                              &adev->virt.mm_table.gpu_addr,
                              (void *)&adev->virt.mm_table.cpu_addr);
        adev->virt.mm_table.gpu_addr = 0;
}


int amdgpu_virt_fw_reserve_get_checksum(void *obj,
                                        unsigned long obj_size,
                                        unsigned int key,
                                        unsigned int chksum)
{
        unsigned int ret = key;
        unsigned long i = 0;
        unsigned char *pos;

        pos = (char *)obj;
        /* calculate checksum */
        for (i = 0; i < obj_size; ++i)
                ret += *(pos + i);
        /* minus the chksum itself */
        pos = (char *)&chksum;
        for (i = 0; i < sizeof(chksum); ++i)
                ret -= *(pos + i);
        return ret;
}

void amdgpu_virt_init_data_exchange(struct amdgpu_device *adev)
{
        uint32_t pf2vf_size = 0;
        uint32_t checksum = 0;
        uint32_t checkval;
        char *str;

        adev->virt.fw_reserve.p_pf2vf = NULL;
        adev->virt.fw_reserve.p_vf2pf = NULL;

        if (adev->fw_vram_usage.va != NULL) {
                adev->virt.fw_reserve.p_pf2vf =
                        (struct amd_sriov_msg_pf2vf_info_header *)(
                        adev->fw_vram_usage.va + AMDGIM_DATAEXCHANGE_OFFSET);
                AMDGPU_FW_VRAM_PF2VF_READ(adev, header.size, &pf2vf_size);
                AMDGPU_FW_VRAM_PF2VF_READ(adev, checksum, &checksum);
                AMDGPU_FW_VRAM_PF2VF_READ(adev, feature_flags, &adev->virt.gim_feature);

                /* pf2vf message must be in 4K */
                if (pf2vf_size > 0 && pf2vf_size < 4096) {
                        checkval = amdgpu_virt_fw_reserve_get_checksum(
                                adev->virt.fw_reserve.p_pf2vf, pf2vf_size,
                                adev->virt.fw_reserve.checksum_key, checksum);
                        if (checkval == checksum) {
                                adev->virt.fw_reserve.p_vf2pf =
                                        ((void *)adev->virt.fw_reserve.p_pf2vf +
                                        pf2vf_size);
                                memset((void *)adev->virt.fw_reserve.p_vf2pf, 0,
                                        sizeof(amdgim_vf2pf_info));
                                AMDGPU_FW_VRAM_VF2PF_WRITE(adev, header.version,
                                        AMDGPU_FW_VRAM_VF2PF_VER);
                                AMDGPU_FW_VRAM_VF2PF_WRITE(adev, header.size,
                                        sizeof(amdgim_vf2pf_info));
                                AMDGPU_FW_VRAM_VF2PF_READ(adev, driver_version,
                                        &str);
#ifdef MODULE
                                if (THIS_MODULE->version != NULL)
                                        strcpy(str, THIS_MODULE->version);
                                else
#endif
                                        strcpy(str, "N/A");
                                AMDGPU_FW_VRAM_VF2PF_WRITE(adev, driver_cert,
                                        0);
                                AMDGPU_FW_VRAM_VF2PF_WRITE(adev, checksum,
                                        amdgpu_virt_fw_reserve_get_checksum(
                                        adev->virt.fw_reserve.p_vf2pf,
                                        pf2vf_size,
                                        adev->virt.fw_reserve.checksum_key, 0));
                        }
                }
        }
}