drivers/gpu/drm/amd/amdkfd/kfd_doorbell.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0 OR MIT
 /*
  * Copyright 2014-2022 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 "kfd_priv.h"
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/idr.h>

 /*
  * This extension supports a kernel level doorbells management for the
  * kernel queues using the first doorbell page reserved for the kernel.
  */

 /*
  * Each device exposes a doorbell aperture, a PCI MMIO aperture that
  * receives 32-bit writes that are passed to queues as wptr values.
  * The doorbells are intended to be written by applications as part
  * of queueing work on user-mode queues.
  * We assign doorbells to applications in PAGE_SIZE-sized and aligned chunks.
  * We map the doorbell address space into user-mode when a process creates
  * its first queue on each device.
  * Although the mapping is done by KFD, it is equivalent to an mmap of
  * the /dev/kfd with the particular device encoded in the mmap offset.
  * There will be other uses for mmap of /dev/kfd, so only a range of
  * offsets (KFD_MMAP_DOORBELL_START-END) is used for doorbells.
  */

 /* # of doorbell bytes allocated for each process. */
 size_t kfd_doorbell_process_slice(struct kfd_dev *kfd)
 {
 	if (!kfd->shared_resources.enable_mes)
 		return roundup(kfd->device_info.doorbell_size *
 				KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
 				PAGE_SIZE);
 	else
 		return amdgpu_mes_doorbell_process_slice(
 					(struct amdgpu_device *)kfd->adev);
 }

 /* Doorbell calculations for device init. */
 int kfd_doorbell_init(struct kfd_dev *kfd)
 {
 	int size = PAGE_SIZE;
 	int r;

 	/*
 	 * Todo: KFD kernel level operations need only one doorbell for
 	 * ring test/HWS. So instead of reserving a whole page here for
 	 * kernel, reserve and consume a doorbell from existing KGD kernel
 	 * doorbell page.
 	 */

 	/* Bitmap to dynamically allocate doorbells from kernel page */
 	kfd->doorbell_bitmap = bitmap_zalloc(size / sizeof(u32), GFP_KERNEL);
 	if (!kfd->doorbell_bitmap) {
 		DRM_ERROR("Failed to allocate kernel doorbell bitmap\n");
 		return -ENOMEM;
 	}

 	/* Alloc a doorbell page for KFD kernel usages */
 	r = amdgpu_bo_create_kernel(kfd->adev,
 				    size,
 				    PAGE_SIZE,
 				    AMDGPU_GEM_DOMAIN_DOORBELL,
 				    &kfd->doorbells,
 				    NULL,
 				    (void **)&kfd->doorbell_kernel_ptr);
 	if (r) {
 		pr_err("failed to allocate kernel doorbells\n");
 		bitmap_free(kfd->doorbell_bitmap);
 		return r;
 	}

 	pr_debug("Doorbell kernel address == %p\n", kfd->doorbell_kernel_ptr);
 	return 0;
 }

 void kfd_doorbell_fini(struct kfd_dev *kfd)
 {
 	bitmap_free(kfd->doorbell_bitmap);
 	amdgpu_bo_free_kernel(&kfd->doorbells, NULL,
 			     (void **)&kfd->doorbell_kernel_ptr);
 }

 int kfd_doorbell_mmap(struct kfd_node *dev, struct kfd_process *process,
 		      struct vm_area_struct *vma)
 {
 	phys_addr_t address;
 	struct kfd_process_device *pdd;

 	/*
 	 * For simplicitly we only allow mapping of the entire doorbell
 	 * allocation of a single device & process.
 	 */
 	if (vma->vm_end - vma->vm_start != kfd_doorbell_process_slice(dev->kfd))
 		return -EINVAL;

 	pdd = kfd_get_process_device_data(dev, process);
 	if (!pdd)
 		return -EINVAL;

 	/* Calculate physical address of doorbell */
 	address = kfd_get_process_doorbells(pdd);
 	if (!address)
 		return -ENOMEM;
 	vm_flags_set(vma, VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_NORESERVE |
 				VM_DONTDUMP | VM_PFNMAP);

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

 	pr_debug("Mapping doorbell page\n"
 		 "     target user address == 0x%08llX\n"
 		 "     physical address    == 0x%08llX\n"
 		 "     vm_flags            == 0x%04lX\n"
 		 "     size                == 0x%04lX\n",
 		 (unsigned long long) vma->vm_start, address, vma->vm_flags,
 		 kfd_doorbell_process_slice(dev->kfd));


 	return io_remap_pfn_range(vma,
 				vma->vm_start,
 				address >> PAGE_SHIFT,
 				kfd_doorbell_process_slice(dev->kfd),
 				vma->vm_page_prot);
 }


 /* get kernel iomem pointer for a doorbell */
 void __iomem *kfd_get_kernel_doorbell(struct kfd_dev *kfd,
 					unsigned int *doorbell_off)
 {
 	u32 inx;

 	mutex_lock(&kfd->doorbell_mutex);
 	inx = find_first_zero_bit(kfd->doorbell_bitmap, PAGE_SIZE / sizeof(u32));

 	__set_bit(inx, kfd->doorbell_bitmap);
 	mutex_unlock(&kfd->doorbell_mutex);

 	if (inx >= KFD_MAX_NUM_OF_QUEUES_PER_PROCESS)
 		return NULL;

 	*doorbell_off = amdgpu_doorbell_index_on_bar(kfd->adev,
 						     kfd->doorbells,
 						     inx,
 						     kfd->device_info.doorbell_size);
 	inx *= 2;

 	pr_debug("Get kernel queue doorbell\n"
 			"     doorbell offset   == 0x%08X\n"
 			"     doorbell index    == 0x%x\n",
 		*doorbell_off, inx);

 	return kfd->doorbell_kernel_ptr + inx;
 }

 void kfd_release_kernel_doorbell(struct kfd_dev *kfd, u32 __iomem *db_addr)
 {
 	unsigned int inx;

 	inx = (unsigned int)(db_addr - kfd->doorbell_kernel_ptr);
 	inx /= 2;

 	mutex_lock(&kfd->doorbell_mutex);
 	__clear_bit(inx, kfd->doorbell_bitmap);
 	mutex_unlock(&kfd->doorbell_mutex);
 }

 void write_kernel_doorbell(void __iomem *db, u32 value)
 {
 	if (db) {
 		writel(value, db);
 		pr_debug("Writing %d to doorbell address %p\n", value, db);
 	}
 }

 void write_kernel_doorbell64(void __iomem *db, u64 value)
 {
 	if (db) {
 		WARN(((unsigned long)db & 7) != 0,
 		     "Unaligned 64-bit doorbell");
 		writeq(value, (u64 __iomem *)db);
 		pr_debug("writing %llu to doorbell address %p\n", value, db);
 	}
 }

 static int init_doorbell_bitmap(struct qcm_process_device *qpd,
 				struct kfd_dev *dev)
 {
 	unsigned int i;
 	int range_start = dev->shared_resources.non_cp_doorbells_start;
 	int range_end = dev->shared_resources.non_cp_doorbells_end;

 	if (!KFD_IS_SOC15(dev))
 		return 0;

 	/* Mask out doorbells reserved for SDMA, IH, and VCN on SOC15. */
 	pr_debug("reserved doorbell 0x%03x - 0x%03x\n", range_start, range_end);
 	pr_debug("reserved doorbell 0x%03x - 0x%03x\n",
 			range_start + KFD_QUEUE_DOORBELL_MIRROR_OFFSET,
 			range_end + KFD_QUEUE_DOORBELL_MIRROR_OFFSET);

 	for (i = 0; i < KFD_MAX_NUM_OF_QUEUES_PER_PROCESS / 2; i++) {
 		if (i >= range_start && i <= range_end) {
 			__set_bit(i, qpd->doorbell_bitmap);
 			__set_bit(i + KFD_QUEUE_DOORBELL_MIRROR_OFFSET,
 				  qpd->doorbell_bitmap);
 		}
 	}

 	return 0;
 }

 phys_addr_t kfd_get_process_doorbells(struct kfd_process_device *pdd)
 {
 	struct amdgpu_device *adev = pdd->dev->adev;
 	uint32_t first_db_index;

 	if (!pdd->qpd.proc_doorbells) {
 		if (kfd_alloc_process_doorbells(pdd->dev->kfd, pdd))
 			/* phys_addr_t 0 is error */
 			return 0;
 	}

 	first_db_index = amdgpu_doorbell_index_on_bar(adev,
 						      pdd->qpd.proc_doorbells,
 						      0,
 						      pdd->dev->kfd->device_info.doorbell_size);
 	return adev->doorbell.base + first_db_index * sizeof(uint32_t);
 }

 int kfd_alloc_process_doorbells(struct kfd_dev *kfd, struct kfd_process_device *pdd)
 {
 	int r;
 	struct qcm_process_device *qpd = &pdd->qpd;

 	/* Allocate bitmap for dynamic doorbell allocation */
 	qpd->doorbell_bitmap = bitmap_zalloc(KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
 					     GFP_KERNEL);
 	if (!qpd->doorbell_bitmap) {
 		DRM_ERROR("Failed to allocate process doorbell bitmap\n");
 		return -ENOMEM;
 	}

 	r = init_doorbell_bitmap(&pdd->qpd, kfd);
 	if (r) {
 		DRM_ERROR("Failed to initialize process doorbells\n");
 		r = -ENOMEM;
 		goto err;
 	}

 	/* Allocate doorbells for this process */
 	r = amdgpu_bo_create_kernel(kfd->adev,
 				    kfd_doorbell_process_slice(kfd),
 				    PAGE_SIZE,
 				    AMDGPU_GEM_DOMAIN_DOORBELL,
 				    &qpd->proc_doorbells,
 				    NULL,
 				    NULL);
 	if (r) {
 		DRM_ERROR("Failed to allocate process doorbells\n");
 		goto err;
 	}
 	return 0;

 err:
 	bitmap_free(qpd->doorbell_bitmap);
 	qpd->doorbell_bitmap = NULL;
 	return r;
 }

 void kfd_free_process_doorbells(struct kfd_dev *kfd, struct kfd_process_device *pdd)
 {
 	struct qcm_process_device *qpd = &pdd->qpd;

 	if (qpd->doorbell_bitmap) {
 		bitmap_free(qpd->doorbell_bitmap);
 		qpd->doorbell_bitmap = NULL;
 	}

 	amdgpu_bo_free_kernel(&qpd->proc_doorbells, NULL, NULL);
 }
	// SPDX-License-Identifier: GPL-2.0 OR MIT
	/*
	* Copyright 2014-2022 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 "kfd_priv.h"
	#include <linux/mm.h>
	#include <linux/mman.h>
	#include <linux/slab.h>
	#include <linux/io.h>
	#include <linux/idr.h>

	/*
	* This extension supports a kernel level doorbells management for the
	* kernel queues using the first doorbell page reserved for the kernel.
	*/

	/*
	* Each device exposes a doorbell aperture, a PCI MMIO aperture that
	* receives 32-bit writes that are passed to queues as wptr values.
	* The doorbells are intended to be written by applications as part
	* of queueing work on user-mode queues.
	* We assign doorbells to applications in PAGE_SIZE-sized and aligned chunks.
	* We map the doorbell address space into user-mode when a process creates
	* its first queue on each device.
	* Although the mapping is done by KFD, it is equivalent to an mmap of
	* the /dev/kfd with the particular device encoded in the mmap offset.
	* There will be other uses for mmap of /dev/kfd, so only a range of
	* offsets (KFD_MMAP_DOORBELL_START-END) is used for doorbells.
	*/

	/* # of doorbell bytes allocated for each process. */
	size_t kfd_doorbell_process_slice(struct kfd_dev *kfd)
	{
	if (!kfd->shared_resources.enable_mes)
	return roundup(kfd->device_info.doorbell_size *
	KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
	PAGE_SIZE);
	else
	return amdgpu_mes_doorbell_process_slice(
	(struct amdgpu_device *)kfd->adev);
	}

	/* Doorbell calculations for device init. */
	int kfd_doorbell_init(struct kfd_dev *kfd)
	{
	int size = PAGE_SIZE;
	int r;

	/*
	* Todo: KFD kernel level operations need only one doorbell for
	* ring test/HWS. So instead of reserving a whole page here for
	* kernel, reserve and consume a doorbell from existing KGD kernel
	* doorbell page.
	*/

	/* Bitmap to dynamically allocate doorbells from kernel page */
	kfd->doorbell_bitmap = bitmap_zalloc(size / sizeof(u32), GFP_KERNEL);
	if (!kfd->doorbell_bitmap) {
	DRM_ERROR("Failed to allocate kernel doorbell bitmap\n");
	return -ENOMEM;
	}

	/* Alloc a doorbell page for KFD kernel usages */
	r = amdgpu_bo_create_kernel(kfd->adev,
	size,
	PAGE_SIZE,
	AMDGPU_GEM_DOMAIN_DOORBELL,
	&kfd->doorbells,
	NULL,
	(void **)&kfd->doorbell_kernel_ptr);
	if (r) {
	pr_err("failed to allocate kernel doorbells\n");
	bitmap_free(kfd->doorbell_bitmap);
	return r;
	}

	pr_debug("Doorbell kernel address == %p\n", kfd->doorbell_kernel_ptr);
	return 0;
	}

	void kfd_doorbell_fini(struct kfd_dev *kfd)
	{
	bitmap_free(kfd->doorbell_bitmap);
	amdgpu_bo_free_kernel(&kfd->doorbells, NULL,
	(void **)&kfd->doorbell_kernel_ptr);
	}

	int kfd_doorbell_mmap(struct kfd_node dev, struct kfd_process process,
	struct vm_area_struct *vma)
	{
	phys_addr_t address;
	struct kfd_process_device *pdd;

	/*
	* For simplicitly we only allow mapping of the entire doorbell
	* allocation of a single device & process.
	*/
	if (vma->vm_end - vma->vm_start != kfd_doorbell_process_slice(dev->kfd))
	return -EINVAL;

	pdd = kfd_get_process_device_data(dev, process);
	if (!pdd)
	return -EINVAL;

	/* Calculate physical address of doorbell */
	address = kfd_get_process_doorbells(pdd);
	if (!address)
	return -ENOMEM;
	vm_flags_set(vma, VM_IO \| VM_DONTCOPY \| VM_DONTEXPAND \| VM_NORESERVE \|
	VM_DONTDUMP \| VM_PFNMAP);

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

	pr_debug("Mapping doorbell page\n"
	" target user address == 0x%08llX\n"
	" physical address == 0x%08llX\n"
	" vm_flags == 0x%04lX\n"
	" size == 0x%04lX\n",
	(unsigned long long) vma->vm_start, address, vma->vm_flags,
	kfd_doorbell_process_slice(dev->kfd));


	return io_remap_pfn_range(vma,
	vma->vm_start,
	address >> PAGE_SHIFT,
	kfd_doorbell_process_slice(dev->kfd),
	vma->vm_page_prot);
	}


	/* get kernel iomem pointer for a doorbell */
	void __iomem kfd_get_kernel_doorbell(struct kfd_dev kfd,
	unsigned int *doorbell_off)
	{
	u32 inx;

	mutex_lock(&kfd->doorbell_mutex);
	inx = find_first_zero_bit(kfd->doorbell_bitmap, PAGE_SIZE / sizeof(u32));

	__set_bit(inx, kfd->doorbell_bitmap);
	mutex_unlock(&kfd->doorbell_mutex);

	if (inx >= KFD_MAX_NUM_OF_QUEUES_PER_PROCESS)
	return NULL;

	*doorbell_off = amdgpu_doorbell_index_on_bar(kfd->adev,
	kfd->doorbells,
	inx,
	kfd->device_info.doorbell_size);
	inx *= 2;

	pr_debug("Get kernel queue doorbell\n"
	" doorbell offset == 0x%08X\n"
	" doorbell index == 0x%x\n",
	*doorbell_off, inx);

	return kfd->doorbell_kernel_ptr + inx;
	}

	void kfd_release_kernel_doorbell(struct kfd_dev kfd, u32 __iomem db_addr)
	{
	unsigned int inx;

	inx = (unsigned int)(db_addr - kfd->doorbell_kernel_ptr);
	inx /= 2;

	mutex_lock(&kfd->doorbell_mutex);
	__clear_bit(inx, kfd->doorbell_bitmap);
	mutex_unlock(&kfd->doorbell_mutex);
	}

	void write_kernel_doorbell(void __iomem *db, u32 value)
	{
	if (db) {
	writel(value, db);
	pr_debug("Writing %d to doorbell address %p\n", value, db);
	}
	}

	void write_kernel_doorbell64(void __iomem *db, u64 value)
	{
	if (db) {
	WARN(((unsigned long)db & 7) != 0,
	"Unaligned 64-bit doorbell");
	writeq(value, (u64 __iomem *)db);
	pr_debug("writing %llu to doorbell address %p\n", value, db);
	}
	}

	static int init_doorbell_bitmap(struct qcm_process_device *qpd,
	struct kfd_dev *dev)
	{
	unsigned int i;
	int range_start = dev->shared_resources.non_cp_doorbells_start;
	int range_end = dev->shared_resources.non_cp_doorbells_end;

	if (!KFD_IS_SOC15(dev))
	return 0;

	/* Mask out doorbells reserved for SDMA, IH, and VCN on SOC15. */
	pr_debug("reserved doorbell 0x%03x - 0x%03x\n", range_start, range_end);
	pr_debug("reserved doorbell 0x%03x - 0x%03x\n",
	range_start + KFD_QUEUE_DOORBELL_MIRROR_OFFSET,
	range_end + KFD_QUEUE_DOORBELL_MIRROR_OFFSET);

	for (i = 0; i < KFD_MAX_NUM_OF_QUEUES_PER_PROCESS / 2; i++) {
	if (i >= range_start && i <= range_end) {
	__set_bit(i, qpd->doorbell_bitmap);
	__set_bit(i + KFD_QUEUE_DOORBELL_MIRROR_OFFSET,
	qpd->doorbell_bitmap);
	}
	}

	return 0;
	}

	phys_addr_t kfd_get_process_doorbells(struct kfd_process_device *pdd)
	{
	struct amdgpu_device *adev = pdd->dev->adev;
	uint32_t first_db_index;

	if (!pdd->qpd.proc_doorbells) {
	if (kfd_alloc_process_doorbells(pdd->dev->kfd, pdd))
	/* phys_addr_t 0 is error */
	return 0;
	}

	first_db_index = amdgpu_doorbell_index_on_bar(adev,
	pdd->qpd.proc_doorbells,
	0,
	pdd->dev->kfd->device_info.doorbell_size);
	return adev->doorbell.base + first_db_index * sizeof(uint32_t);
	}

	int kfd_alloc_process_doorbells(struct kfd_dev kfd, struct kfd_process_device pdd)
	{
	int r;
	struct qcm_process_device *qpd = &pdd->qpd;

	/* Allocate bitmap for dynamic doorbell allocation */
	qpd->doorbell_bitmap = bitmap_zalloc(KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
	GFP_KERNEL);
	if (!qpd->doorbell_bitmap) {
	DRM_ERROR("Failed to allocate process doorbell bitmap\n");
	return -ENOMEM;
	}

	r = init_doorbell_bitmap(&pdd->qpd, kfd);
	if (r) {
	DRM_ERROR("Failed to initialize process doorbells\n");
	r = -ENOMEM;
	goto err;
	}

	/* Allocate doorbells for this process */
	r = amdgpu_bo_create_kernel(kfd->adev,
	kfd_doorbell_process_slice(kfd),
	PAGE_SIZE,
	AMDGPU_GEM_DOMAIN_DOORBELL,
	&qpd->proc_doorbells,
	NULL,
	NULL);
	if (r) {
	DRM_ERROR("Failed to allocate process doorbells\n");
	goto err;
	}
	return 0;

	err:
	bitmap_free(qpd->doorbell_bitmap);
	qpd->doorbell_bitmap = NULL;
	return r;
	}

	void kfd_free_process_doorbells(struct kfd_dev kfd, struct kfd_process_device pdd)
	{
	struct qcm_process_device *qpd = &pdd->qpd;

	if (qpd->doorbell_bitmap) {
	bitmap_free(qpd->doorbell_bitmap);
	qpd->doorbell_bitmap = NULL;
	}

	amdgpu_bo_free_kernel(&qpd->proc_doorbells, NULL, NULL);
	}