// 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);
}
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