blob: 73c535193a984b385f65986c9b1c0d3b79f1f5b4 [file] [log] [blame]
// SPDX-License-Identifier: MIT
/*
* Copyright © 2022 Intel Corporation
*/
#include "xe_gt_pagefault.h"
#include <linux/bitfield.h>
#include <linux/circ_buf.h>
#include <drm/drm_exec.h>
#include <drm/drm_managed.h>
#include <drm/ttm/ttm_execbuf_util.h>
#include "abi/guc_actions_abi.h"
#include "xe_bo.h"
#include "xe_gt.h"
#include "xe_gt_tlb_invalidation.h"
#include "xe_guc.h"
#include "xe_guc_ct.h"
#include "xe_migrate.h"
#include "xe_pt.h"
#include "xe_trace.h"
#include "xe_vm.h"
struct pagefault {
u64 page_addr;
u32 asid;
u16 pdata;
u8 vfid;
u8 access_type;
u8 fault_type;
u8 fault_level;
u8 engine_class;
u8 engine_instance;
u8 fault_unsuccessful;
bool trva_fault;
};
enum access_type {
ACCESS_TYPE_READ = 0,
ACCESS_TYPE_WRITE = 1,
ACCESS_TYPE_ATOMIC = 2,
ACCESS_TYPE_RESERVED = 3,
};
enum fault_type {
NOT_PRESENT = 0,
WRITE_ACCESS_VIOLATION = 1,
ATOMIC_ACCESS_VIOLATION = 2,
};
struct acc {
u64 va_range_base;
u32 asid;
u32 sub_granularity;
u8 granularity;
u8 vfid;
u8 access_type;
u8 engine_class;
u8 engine_instance;
};
static bool access_is_atomic(enum access_type access_type)
{
return access_type == ACCESS_TYPE_ATOMIC;
}
static bool vma_is_valid(struct xe_tile *tile, struct xe_vma *vma)
{
return BIT(tile->id) & vma->tile_present &&
!(BIT(tile->id) & vma->usm.tile_invalidated);
}
static bool vma_matches(struct xe_vma *vma, u64 page_addr)
{
if (page_addr > xe_vma_end(vma) - 1 ||
page_addr + SZ_4K - 1 < xe_vma_start(vma))
return false;
return true;
}
static struct xe_vma *lookup_vma(struct xe_vm *vm, u64 page_addr)
{
struct xe_vma *vma = NULL;
if (vm->usm.last_fault_vma) { /* Fast lookup */
if (vma_matches(vm->usm.last_fault_vma, page_addr))
vma = vm->usm.last_fault_vma;
}
if (!vma)
vma = xe_vm_find_overlapping_vma(vm, page_addr, SZ_4K);
return vma;
}
static int xe_pf_begin(struct drm_exec *exec, struct xe_vma *vma,
bool atomic, unsigned int id)
{
struct xe_bo *bo = xe_vma_bo(vma);
struct xe_vm *vm = xe_vma_vm(vma);
unsigned int num_shared = 2; /* slots for bind + move */
int err;
err = xe_vm_prepare_vma(exec, vma, num_shared);
if (err)
return err;
if (atomic && IS_DGFX(vm->xe)) {
if (xe_vma_is_userptr(vma)) {
err = -EACCES;
return err;
}
/* Migrate to VRAM, move should invalidate the VMA first */
err = xe_bo_migrate(bo, XE_PL_VRAM0 + id);
if (err)
return err;
} else if (bo) {
/* Create backing store if needed */
err = xe_bo_validate(bo, vm, true);
if (err)
return err;
}
return 0;
}
static int handle_pagefault(struct xe_gt *gt, struct pagefault *pf)
{
struct xe_device *xe = gt_to_xe(gt);
struct xe_tile *tile = gt_to_tile(gt);
struct drm_exec exec;
struct xe_vm *vm;
struct xe_vma *vma = NULL;
struct dma_fence *fence;
bool write_locked;
int ret = 0;
bool atomic;
/* SW isn't expected to handle TRTT faults */
if (pf->trva_fault)
return -EFAULT;
/* ASID to VM */
mutex_lock(&xe->usm.lock);
vm = xa_load(&xe->usm.asid_to_vm, pf->asid);
if (vm && xe_vm_in_fault_mode(vm))
xe_vm_get(vm);
else
vm = NULL;
mutex_unlock(&xe->usm.lock);
if (!vm)
return -EINVAL;
retry_userptr:
/*
* TODO: Avoid exclusive lock if VM doesn't have userptrs, or
* start out read-locked?
*/
down_write(&vm->lock);
write_locked = true;
vma = lookup_vma(vm, pf->page_addr);
if (!vma) {
ret = -EINVAL;
goto unlock_vm;
}
if (!xe_vma_is_userptr(vma) ||
!xe_vma_userptr_check_repin(to_userptr_vma(vma))) {
downgrade_write(&vm->lock);
write_locked = false;
}
trace_xe_vma_pagefault(vma);
atomic = access_is_atomic(pf->access_type);
/* Check if VMA is valid */
if (vma_is_valid(tile, vma) && !atomic)
goto unlock_vm;
/* TODO: Validate fault */
if (xe_vma_is_userptr(vma) && write_locked) {
struct xe_userptr_vma *uvma = to_userptr_vma(vma);
spin_lock(&vm->userptr.invalidated_lock);
list_del_init(&uvma->userptr.invalidate_link);
spin_unlock(&vm->userptr.invalidated_lock);
ret = xe_vma_userptr_pin_pages(uvma);
if (ret)
goto unlock_vm;
downgrade_write(&vm->lock);
write_locked = false;
}
/* Lock VM and BOs dma-resv */
drm_exec_init(&exec, 0, 0);
drm_exec_until_all_locked(&exec) {
ret = xe_pf_begin(&exec, vma, atomic, tile->id);
drm_exec_retry_on_contention(&exec);
if (ret)
goto unlock_dma_resv;
}
/* Bind VMA only to the GT that has faulted */
trace_xe_vma_pf_bind(vma);
fence = __xe_pt_bind_vma(tile, vma, xe_tile_migrate_engine(tile), NULL, 0,
vma->tile_present & BIT(tile->id));
if (IS_ERR(fence)) {
ret = PTR_ERR(fence);
goto unlock_dma_resv;
}
/*
* XXX: Should we drop the lock before waiting? This only helps if doing
* GPU binds which is currently only done if we have to wait for more
* than 10ms on a move.
*/
dma_fence_wait(fence, false);
dma_fence_put(fence);
if (xe_vma_is_userptr(vma))
ret = xe_vma_userptr_check_repin(to_userptr_vma(vma));
vma->usm.tile_invalidated &= ~BIT(tile->id);
unlock_dma_resv:
drm_exec_fini(&exec);
unlock_vm:
if (!ret)
vm->usm.last_fault_vma = vma;
if (write_locked)
up_write(&vm->lock);
else
up_read(&vm->lock);
if (ret == -EAGAIN)
goto retry_userptr;
if (!ret) {
ret = xe_gt_tlb_invalidation_vma(gt, NULL, vma);
if (ret >= 0)
ret = 0;
}
xe_vm_put(vm);
return ret;
}
static int send_pagefault_reply(struct xe_guc *guc,
struct xe_guc_pagefault_reply *reply)
{
u32 action[] = {
XE_GUC_ACTION_PAGE_FAULT_RES_DESC,
reply->dw0,
reply->dw1,
};
return xe_guc_ct_send(&guc->ct, action, ARRAY_SIZE(action), 0, 0);
}
static void print_pagefault(struct xe_device *xe, struct pagefault *pf)
{
drm_dbg(&xe->drm, "\n\tASID: %d\n"
"\tVFID: %d\n"
"\tPDATA: 0x%04x\n"
"\tFaulted Address: 0x%08x%08x\n"
"\tFaultType: %d\n"
"\tAccessType: %d\n"
"\tFaultLevel: %d\n"
"\tEngineClass: %d\n"
"\tEngineInstance: %d\n",
pf->asid, pf->vfid, pf->pdata, upper_32_bits(pf->page_addr),
lower_32_bits(pf->page_addr),
pf->fault_type, pf->access_type, pf->fault_level,
pf->engine_class, pf->engine_instance);
}
#define PF_MSG_LEN_DW 4
static bool get_pagefault(struct pf_queue *pf_queue, struct pagefault *pf)
{
const struct xe_guc_pagefault_desc *desc;
bool ret = false;
spin_lock_irq(&pf_queue->lock);
if (pf_queue->tail != pf_queue->head) {
desc = (const struct xe_guc_pagefault_desc *)
(pf_queue->data + pf_queue->tail);
pf->fault_level = FIELD_GET(PFD_FAULT_LEVEL, desc->dw0);
pf->trva_fault = FIELD_GET(XE2_PFD_TRVA_FAULT, desc->dw0);
pf->engine_class = FIELD_GET(PFD_ENG_CLASS, desc->dw0);
pf->engine_instance = FIELD_GET(PFD_ENG_INSTANCE, desc->dw0);
pf->pdata = FIELD_GET(PFD_PDATA_HI, desc->dw1) <<
PFD_PDATA_HI_SHIFT;
pf->pdata |= FIELD_GET(PFD_PDATA_LO, desc->dw0);
pf->asid = FIELD_GET(PFD_ASID, desc->dw1);
pf->vfid = FIELD_GET(PFD_VFID, desc->dw2);
pf->access_type = FIELD_GET(PFD_ACCESS_TYPE, desc->dw2);
pf->fault_type = FIELD_GET(PFD_FAULT_TYPE, desc->dw2);
pf->page_addr = (u64)(FIELD_GET(PFD_VIRTUAL_ADDR_HI, desc->dw3)) <<
PFD_VIRTUAL_ADDR_HI_SHIFT;
pf->page_addr |= FIELD_GET(PFD_VIRTUAL_ADDR_LO, desc->dw2) <<
PFD_VIRTUAL_ADDR_LO_SHIFT;
pf_queue->tail = (pf_queue->tail + PF_MSG_LEN_DW) %
PF_QUEUE_NUM_DW;
ret = true;
}
spin_unlock_irq(&pf_queue->lock);
return ret;
}
static bool pf_queue_full(struct pf_queue *pf_queue)
{
lockdep_assert_held(&pf_queue->lock);
return CIRC_SPACE(pf_queue->head, pf_queue->tail, PF_QUEUE_NUM_DW) <=
PF_MSG_LEN_DW;
}
int xe_guc_pagefault_handler(struct xe_guc *guc, u32 *msg, u32 len)
{
struct xe_gt *gt = guc_to_gt(guc);
struct xe_device *xe = gt_to_xe(gt);
struct pf_queue *pf_queue;
unsigned long flags;
u32 asid;
bool full;
/*
* The below logic doesn't work unless PF_QUEUE_NUM_DW % PF_MSG_LEN_DW == 0
*/
BUILD_BUG_ON(PF_QUEUE_NUM_DW % PF_MSG_LEN_DW);
if (unlikely(len != PF_MSG_LEN_DW))
return -EPROTO;
asid = FIELD_GET(PFD_ASID, msg[1]);
pf_queue = gt->usm.pf_queue + (asid % NUM_PF_QUEUE);
spin_lock_irqsave(&pf_queue->lock, flags);
full = pf_queue_full(pf_queue);
if (!full) {
memcpy(pf_queue->data + pf_queue->head, msg, len * sizeof(u32));
pf_queue->head = (pf_queue->head + len) % PF_QUEUE_NUM_DW;
queue_work(gt->usm.pf_wq, &pf_queue->worker);
} else {
drm_warn(&xe->drm, "PF Queue full, shouldn't be possible");
}
spin_unlock_irqrestore(&pf_queue->lock, flags);
return full ? -ENOSPC : 0;
}
#define USM_QUEUE_MAX_RUNTIME_MS 20
static void pf_queue_work_func(struct work_struct *w)
{
struct pf_queue *pf_queue = container_of(w, struct pf_queue, worker);
struct xe_gt *gt = pf_queue->gt;
struct xe_device *xe = gt_to_xe(gt);
struct xe_guc_pagefault_reply reply = {};
struct pagefault pf = {};
unsigned long threshold;
int ret;
threshold = jiffies + msecs_to_jiffies(USM_QUEUE_MAX_RUNTIME_MS);
while (get_pagefault(pf_queue, &pf)) {
ret = handle_pagefault(gt, &pf);
if (unlikely(ret)) {
print_pagefault(xe, &pf);
pf.fault_unsuccessful = 1;
drm_dbg(&xe->drm, "Fault response: Unsuccessful %d\n", ret);
}
reply.dw0 = FIELD_PREP(PFR_VALID, 1) |
FIELD_PREP(PFR_SUCCESS, pf.fault_unsuccessful) |
FIELD_PREP(PFR_REPLY, PFR_ACCESS) |
FIELD_PREP(PFR_DESC_TYPE, FAULT_RESPONSE_DESC) |
FIELD_PREP(PFR_ASID, pf.asid);
reply.dw1 = FIELD_PREP(PFR_VFID, pf.vfid) |
FIELD_PREP(PFR_ENG_INSTANCE, pf.engine_instance) |
FIELD_PREP(PFR_ENG_CLASS, pf.engine_class) |
FIELD_PREP(PFR_PDATA, pf.pdata);
send_pagefault_reply(&gt->uc.guc, &reply);
if (time_after(jiffies, threshold) &&
pf_queue->tail != pf_queue->head) {
queue_work(gt->usm.pf_wq, w);
break;
}
}
}
static void acc_queue_work_func(struct work_struct *w);
int xe_gt_pagefault_init(struct xe_gt *gt)
{
struct xe_device *xe = gt_to_xe(gt);
int i;
if (!xe->info.has_usm)
return 0;
for (i = 0; i < NUM_PF_QUEUE; ++i) {
gt->usm.pf_queue[i].gt = gt;
spin_lock_init(&gt->usm.pf_queue[i].lock);
INIT_WORK(&gt->usm.pf_queue[i].worker, pf_queue_work_func);
}
for (i = 0; i < NUM_ACC_QUEUE; ++i) {
gt->usm.acc_queue[i].gt = gt;
spin_lock_init(&gt->usm.acc_queue[i].lock);
INIT_WORK(&gt->usm.acc_queue[i].worker, acc_queue_work_func);
}
gt->usm.pf_wq = alloc_workqueue("xe_gt_page_fault_work_queue",
WQ_UNBOUND | WQ_HIGHPRI, NUM_PF_QUEUE);
if (!gt->usm.pf_wq)
return -ENOMEM;
gt->usm.acc_wq = alloc_workqueue("xe_gt_access_counter_work_queue",
WQ_UNBOUND | WQ_HIGHPRI,
NUM_ACC_QUEUE);
if (!gt->usm.acc_wq)
return -ENOMEM;
return 0;
}
void xe_gt_pagefault_reset(struct xe_gt *gt)
{
struct xe_device *xe = gt_to_xe(gt);
int i;
if (!xe->info.has_usm)
return;
for (i = 0; i < NUM_PF_QUEUE; ++i) {
spin_lock_irq(&gt->usm.pf_queue[i].lock);
gt->usm.pf_queue[i].head = 0;
gt->usm.pf_queue[i].tail = 0;
spin_unlock_irq(&gt->usm.pf_queue[i].lock);
}
for (i = 0; i < NUM_ACC_QUEUE; ++i) {
spin_lock(&gt->usm.acc_queue[i].lock);
gt->usm.acc_queue[i].head = 0;
gt->usm.acc_queue[i].tail = 0;
spin_unlock(&gt->usm.acc_queue[i].lock);
}
}
static int granularity_in_byte(int val)
{
switch (val) {
case 0:
return SZ_128K;
case 1:
return SZ_2M;
case 2:
return SZ_16M;
case 3:
return SZ_64M;
default:
return 0;
}
}
static int sub_granularity_in_byte(int val)
{
return (granularity_in_byte(val) / 32);
}
static void print_acc(struct xe_device *xe, struct acc *acc)
{
drm_warn(&xe->drm, "Access counter request:\n"
"\tType: %s\n"
"\tASID: %d\n"
"\tVFID: %d\n"
"\tEngine: %d:%d\n"
"\tGranularity: 0x%x KB Region/ %d KB sub-granularity\n"
"\tSub_Granularity Vector: 0x%08x\n"
"\tVA Range base: 0x%016llx\n",
acc->access_type ? "AC_NTFY_VAL" : "AC_TRIG_VAL",
acc->asid, acc->vfid, acc->engine_class, acc->engine_instance,
granularity_in_byte(acc->granularity) / SZ_1K,
sub_granularity_in_byte(acc->granularity) / SZ_1K,
acc->sub_granularity, acc->va_range_base);
}
static struct xe_vma *get_acc_vma(struct xe_vm *vm, struct acc *acc)
{
u64 page_va = acc->va_range_base + (ffs(acc->sub_granularity) - 1) *
sub_granularity_in_byte(acc->granularity);
return xe_vm_find_overlapping_vma(vm, page_va, SZ_4K);
}
static int handle_acc(struct xe_gt *gt, struct acc *acc)
{
struct xe_device *xe = gt_to_xe(gt);
struct xe_tile *tile = gt_to_tile(gt);
struct drm_exec exec;
struct xe_vm *vm;
struct xe_vma *vma;
int ret = 0;
/* We only support ACC_TRIGGER at the moment */
if (acc->access_type != ACC_TRIGGER)
return -EINVAL;
/* ASID to VM */
mutex_lock(&xe->usm.lock);
vm = xa_load(&xe->usm.asid_to_vm, acc->asid);
if (vm)
xe_vm_get(vm);
mutex_unlock(&xe->usm.lock);
if (!vm || !xe_vm_in_fault_mode(vm))
return -EINVAL;
down_read(&vm->lock);
/* Lookup VMA */
vma = get_acc_vma(vm, acc);
if (!vma) {
ret = -EINVAL;
goto unlock_vm;
}
trace_xe_vma_acc(vma);
/* Userptr or null can't be migrated, nothing to do */
if (xe_vma_has_no_bo(vma))
goto unlock_vm;
/* Lock VM and BOs dma-resv */
drm_exec_init(&exec, 0, 0);
drm_exec_until_all_locked(&exec) {
ret = xe_pf_begin(&exec, vma, true, tile->id);
drm_exec_retry_on_contention(&exec);
if (ret)
break;
}
drm_exec_fini(&exec);
unlock_vm:
up_read(&vm->lock);
xe_vm_put(vm);
return ret;
}
#define make_u64(hi__, low__) ((u64)(hi__) << 32 | (u64)(low__))
#define ACC_MSG_LEN_DW 4
static bool get_acc(struct acc_queue *acc_queue, struct acc *acc)
{
const struct xe_guc_acc_desc *desc;
bool ret = false;
spin_lock(&acc_queue->lock);
if (acc_queue->tail != acc_queue->head) {
desc = (const struct xe_guc_acc_desc *)
(acc_queue->data + acc_queue->tail);
acc->granularity = FIELD_GET(ACC_GRANULARITY, desc->dw2);
acc->sub_granularity = FIELD_GET(ACC_SUBG_HI, desc->dw1) << 31 |
FIELD_GET(ACC_SUBG_LO, desc->dw0);
acc->engine_class = FIELD_GET(ACC_ENG_CLASS, desc->dw1);
acc->engine_instance = FIELD_GET(ACC_ENG_INSTANCE, desc->dw1);
acc->asid = FIELD_GET(ACC_ASID, desc->dw1);
acc->vfid = FIELD_GET(ACC_VFID, desc->dw2);
acc->access_type = FIELD_GET(ACC_TYPE, desc->dw0);
acc->va_range_base = make_u64(desc->dw3 & ACC_VIRTUAL_ADDR_RANGE_HI,
desc->dw2 & ACC_VIRTUAL_ADDR_RANGE_LO);
acc_queue->tail = (acc_queue->tail + ACC_MSG_LEN_DW) %
ACC_QUEUE_NUM_DW;
ret = true;
}
spin_unlock(&acc_queue->lock);
return ret;
}
static void acc_queue_work_func(struct work_struct *w)
{
struct acc_queue *acc_queue = container_of(w, struct acc_queue, worker);
struct xe_gt *gt = acc_queue->gt;
struct xe_device *xe = gt_to_xe(gt);
struct acc acc = {};
unsigned long threshold;
int ret;
threshold = jiffies + msecs_to_jiffies(USM_QUEUE_MAX_RUNTIME_MS);
while (get_acc(acc_queue, &acc)) {
ret = handle_acc(gt, &acc);
if (unlikely(ret)) {
print_acc(xe, &acc);
drm_warn(&xe->drm, "ACC: Unsuccessful %d\n", ret);
}
if (time_after(jiffies, threshold) &&
acc_queue->tail != acc_queue->head) {
queue_work(gt->usm.acc_wq, w);
break;
}
}
}
static bool acc_queue_full(struct acc_queue *acc_queue)
{
lockdep_assert_held(&acc_queue->lock);
return CIRC_SPACE(acc_queue->head, acc_queue->tail, ACC_QUEUE_NUM_DW) <=
ACC_MSG_LEN_DW;
}
int xe_guc_access_counter_notify_handler(struct xe_guc *guc, u32 *msg, u32 len)
{
struct xe_gt *gt = guc_to_gt(guc);
struct acc_queue *acc_queue;
u32 asid;
bool full;
/*
* The below logic doesn't work unless ACC_QUEUE_NUM_DW % ACC_MSG_LEN_DW == 0
*/
BUILD_BUG_ON(ACC_QUEUE_NUM_DW % ACC_MSG_LEN_DW);
if (unlikely(len != ACC_MSG_LEN_DW))
return -EPROTO;
asid = FIELD_GET(ACC_ASID, msg[1]);
acc_queue = &gt->usm.acc_queue[asid % NUM_ACC_QUEUE];
spin_lock(&acc_queue->lock);
full = acc_queue_full(acc_queue);
if (!full) {
memcpy(acc_queue->data + acc_queue->head, msg,
len * sizeof(u32));
acc_queue->head = (acc_queue->head + len) % ACC_QUEUE_NUM_DW;
queue_work(gt->usm.acc_wq, &acc_queue->worker);
} else {
drm_warn(&gt_to_xe(gt)->drm, "ACC Queue full, dropping ACC");
}
spin_unlock(&acc_queue->lock);
return full ? -ENOSPC : 0;
}