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

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
Extension
.c
Size
6904 bytes
Lines
245
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// 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)
{
	if (amdgpu_device_skip_hw_access(adev))
		return 0;

	if (index < adev->doorbell.num_kernel_doorbells)
		return readl(adev->doorbell.cpu_addr + index);

	dev_err(adev->dev, "reading beyond doorbell aperture: 0x%08x!\n",
		index);
	return 0;
}

/**
 * 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)
{
	if (amdgpu_device_skip_hw_access(adev))
		return;

	if (index < adev->doorbell.num_kernel_doorbells)
		writel(v, adev->doorbell.cpu_addr + index);
	else
		dev_err(adev->dev,
			"writing beyond doorbell aperture: 0x%08x!\n", index);
}

/**
 * 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)
{
	if (amdgpu_device_skip_hw_access(adev))
		return 0;

	if (index < adev->doorbell.num_kernel_doorbells)
		return atomic64_read((atomic64_t *)(adev->doorbell.cpu_addr + index));

	dev_err(adev->dev, "reading beyond doorbell aperture: 0x%08x!\n",
		index);
	return 0;

Annotation

Implementation Notes