blob: e621eba63126a09dc65f33ee59dd6bf47785e06d [file] [log] [blame]
/*
* Copyright 2014 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>
/*
* This extension supports a kernel level doorbells management for
* the kernel queues.
* Basically the last doorbells page is devoted to kernel queues
* and that's assures that any user process won't get access to the
* kernel doorbells page
*/
#define KERNEL_DOORBELL_PASID 1
#define KFD_SIZE_OF_DOORBELL_IN_BYTES 4
/*
* 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. */
static inline size_t doorbell_process_allocation(void)
{
return roundup(KFD_SIZE_OF_DOORBELL_IN_BYTES *
KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
PAGE_SIZE);
}
/* Doorbell calculations for device init. */
void kfd_doorbell_init(struct kfd_dev *kfd)
{
size_t doorbell_start_offset;
size_t doorbell_aperture_size;
size_t doorbell_process_limit;
/*
* We start with calculations in bytes because the input data might
* only be byte-aligned.
* Only after we have done the rounding can we assume any alignment.
*/
doorbell_start_offset =
roundup(kfd->shared_resources.doorbell_start_offset,
doorbell_process_allocation());
doorbell_aperture_size =
rounddown(kfd->shared_resources.doorbell_aperture_size,
doorbell_process_allocation());
if (doorbell_aperture_size > doorbell_start_offset)
doorbell_process_limit =
(doorbell_aperture_size - doorbell_start_offset) /
doorbell_process_allocation();
else
doorbell_process_limit = 0;
kfd->doorbell_base = kfd->shared_resources.doorbell_physical_address +
doorbell_start_offset;
kfd->doorbell_id_offset = doorbell_start_offset / sizeof(u32);
kfd->doorbell_process_limit = doorbell_process_limit - 1;
kfd->doorbell_kernel_ptr = ioremap(kfd->doorbell_base,
doorbell_process_allocation());
BUG_ON(!kfd->doorbell_kernel_ptr);
pr_debug("kfd: doorbell initialization:\n");
pr_debug("kfd: doorbell base == 0x%08lX\n",
(uintptr_t)kfd->doorbell_base);
pr_debug("kfd: doorbell_id_offset == 0x%08lX\n",
kfd->doorbell_id_offset);
pr_debug("kfd: doorbell_process_limit == 0x%08lX\n",
doorbell_process_limit);
pr_debug("kfd: doorbell_kernel_offset == 0x%08lX\n",
(uintptr_t)kfd->doorbell_base);
pr_debug("kfd: doorbell aperture size == 0x%08lX\n",
kfd->shared_resources.doorbell_aperture_size);
pr_debug("kfd: doorbell kernel address == 0x%08lX\n",
(uintptr_t)kfd->doorbell_kernel_ptr);
}
int kfd_doorbell_mmap(struct kfd_process *process, struct vm_area_struct *vma)
{
phys_addr_t address;
struct kfd_dev *dev;
/*
* For simplicitly we only allow mapping of the entire doorbell
* allocation of a single device & process.
*/
if (vma->vm_end - vma->vm_start != doorbell_process_allocation())
return -EINVAL;
/* Find kfd device according to gpu id */
dev = kfd_device_by_id(vma->vm_pgoff);
if (dev == NULL)
return -EINVAL;
/* Calculate physical address of doorbell */
address = kfd_get_process_doorbells(dev, process);
vma->vm_flags |= 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");
pr_debug(" target user address == 0x%08llX\n",
(unsigned long long) vma->vm_start);
pr_debug(" physical address == 0x%08llX\n", address);
pr_debug(" vm_flags == 0x%04lX\n", vma->vm_flags);
pr_debug(" size == 0x%04lX\n",
doorbell_process_allocation());
return io_remap_pfn_range(vma,
vma->vm_start,
address >> PAGE_SHIFT,
doorbell_process_allocation(),
vma->vm_page_prot);
}
/* get kernel iomem pointer for a doorbell */
u32 __iomem *kfd_get_kernel_doorbell(struct kfd_dev *kfd,
unsigned int *doorbell_off)
{
u32 inx;
BUG_ON(!kfd || !doorbell_off);
mutex_lock(&kfd->doorbell_mutex);
inx = find_first_zero_bit(kfd->doorbell_available_index,
KFD_MAX_NUM_OF_QUEUES_PER_PROCESS);
__set_bit(inx, kfd->doorbell_available_index);
mutex_unlock(&kfd->doorbell_mutex);
if (inx >= KFD_MAX_NUM_OF_QUEUES_PER_PROCESS)
return NULL;
/*
* Calculating the kernel doorbell offset using "faked" kernel
* pasid that allocated for kernel queues only
*/
*doorbell_off = KERNEL_DOORBELL_PASID * (doorbell_process_allocation() /
sizeof(u32)) + inx;
pr_debug("kfd: get kernel queue doorbell\n"
" doorbell offset == 0x%08d\n"
" kernel address == 0x%08lX\n",
*doorbell_off, (uintptr_t)(kfd->doorbell_kernel_ptr + inx));
return kfd->doorbell_kernel_ptr + inx;
}
void kfd_release_kernel_doorbell(struct kfd_dev *kfd, u32 __iomem *db_addr)
{
unsigned int inx;
BUG_ON(!kfd || !db_addr);
inx = (unsigned int)(db_addr - kfd->doorbell_kernel_ptr);
mutex_lock(&kfd->doorbell_mutex);
__clear_bit(inx, kfd->doorbell_available_index);
mutex_unlock(&kfd->doorbell_mutex);
}
inline void write_kernel_doorbell(u32 __iomem *db, u32 value)
{
if (db) {
writel(value, db);
pr_debug("writing %d to doorbell address 0x%p\n", value, db);
}
}
/*
* queue_ids are in the range [0,MAX_PROCESS_QUEUES) and are mapped 1:1
* to doorbells with the process's doorbell page
*/
unsigned int kfd_queue_id_to_doorbell(struct kfd_dev *kfd,
struct kfd_process *process,
unsigned int queue_id)
{
/*
* doorbell_id_offset accounts for doorbells taken by KGD.
* pasid * doorbell_process_allocation/sizeof(u32) adjusts
* to the process's doorbells
*/
return kfd->doorbell_id_offset +
process->pasid * (doorbell_process_allocation()/sizeof(u32)) +
queue_id;
}
uint64_t kfd_get_number_elems(struct kfd_dev *kfd)
{
uint64_t num_of_elems = (kfd->shared_resources.doorbell_aperture_size -
kfd->shared_resources.doorbell_start_offset) /
doorbell_process_allocation() + 1;
return num_of_elems;
}
phys_addr_t kfd_get_process_doorbells(struct kfd_dev *dev,
struct kfd_process *process)
{
return dev->doorbell_base +
process->pasid * doorbell_process_allocation();
}