linux/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c

// SPDX-License-Identifier: MIT
/*
 * Copyright 2022 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 "amdgpu.h"

/**
 * amdgpu_mm_rdoorbell - read a doorbell dword
 *
 * @adev: amdgpu_device pointer
 * @index: doorbell index
 *
 * Returns the value in the doorbell aperture at the
 * requested doorbell index (CIK).
 */
u32 amdgpu_mm_rdoorbell(struct amdgpu_device *adev, u32 index)
{ … }

/**
 * amdgpu_mm_wdoorbell - write a doorbell dword
 *
 * @adev: amdgpu_device pointer
 * @index: doorbell index
 * @v: value to write
 *
 * Writes @v to the doorbell aperture at the
 * requested doorbell index (CIK).
 */
void amdgpu_mm_wdoorbell(struct amdgpu_device *adev, u32 index, u32 v)
{ … }

/**
 * amdgpu_mm_rdoorbell64 - read a doorbell Qword
 *
 * @adev: amdgpu_device pointer
 * @index: doorbell index
 *
 * Returns the value in the doorbell aperture at the
 * requested doorbell index (VEGA10+).
 */
u64 amdgpu_mm_rdoorbell64(struct amdgpu_device *adev, u32 index)
{ … }

/**
 * amdgpu_mm_wdoorbell64 - write a doorbell Qword
 *
 * @adev: amdgpu_device pointer
 * @index: doorbell index
 * @v: value to write
 *
 * Writes @v to the doorbell aperture at the
 * requested doorbell index (VEGA10+).
 */
void amdgpu_mm_wdoorbell64(struct amdgpu_device *adev, u32 index, u64 v)
{ … }

/**
 * amdgpu_doorbell_index_on_bar - Find doorbell's absolute offset in BAR
 *
 * @adev: amdgpu_device pointer
 * @db_bo: doorbell object's bo
 * @doorbell_index: doorbell relative index in this doorbell object
 * @db_size: doorbell size is in byte
 *
 * returns doorbell's absolute index in BAR
 */
uint32_t amdgpu_doorbell_index_on_bar(struct amdgpu_device *adev,
				      struct amdgpu_bo *db_bo,
				      uint32_t doorbell_index,
				      uint32_t db_size)
{ … }

/**
 * amdgpu_doorbell_create_kernel_doorbells - Create kernel doorbells for graphics
 *
 * @adev: amdgpu_device pointer
 *
 * Creates doorbells for graphics driver usages.
 * returns 0 on success, error otherwise.
 */
int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device *adev)
{ … }

/*
 * GPU doorbell aperture helpers function.
 */
/**
 * amdgpu_doorbell_init - Init doorbell driver information.
 *
 * @adev: amdgpu_device pointer
 *
 * Init doorbell driver information (CIK)
 * Returns 0 on success, error on failure.
 */
int amdgpu_doorbell_init(struct amdgpu_device *adev)
{ … }

/**
 * amdgpu_doorbell_fini - Tear down doorbell driver information.
 *
 * @adev: amdgpu_device pointer
 *
 * Tear down doorbell driver information (CIK)
 */
void amdgpu_doorbell_fini(struct amdgpu_device *adev)
{ … }