blob: f03e077f81a04fcb9344f8c634856acab516c6f1 [file] [log] [blame]
// SPDX-License-Identifier: MIT
/*
* Copyright © 2023 Intel Corporation
*/
#include "xe_gt_tlb_invalidation.h"
#include "abi/guc_actions_abi.h"
#include "xe_device.h"
#include "xe_gt.h"
#include "xe_gt_printk.h"
#include "xe_guc.h"
#include "xe_guc_ct.h"
#include "xe_trace.h"
#define TLB_TIMEOUT (HZ / 4)
static void xe_gt_tlb_fence_timeout(struct work_struct *work)
{
struct xe_gt *gt = container_of(work, struct xe_gt,
tlb_invalidation.fence_tdr.work);
struct xe_gt_tlb_invalidation_fence *fence, *next;
spin_lock_irq(&gt->tlb_invalidation.pending_lock);
list_for_each_entry_safe(fence, next,
&gt->tlb_invalidation.pending_fences, link) {
s64 since_inval_ms = ktime_ms_delta(ktime_get(),
fence->invalidation_time);
if (msecs_to_jiffies(since_inval_ms) < TLB_TIMEOUT)
break;
trace_xe_gt_tlb_invalidation_fence_timeout(fence);
xe_gt_err(gt, "TLB invalidation fence timeout, seqno=%d recv=%d",
fence->seqno, gt->tlb_invalidation.seqno_recv);
list_del(&fence->link);
fence->base.error = -ETIME;
dma_fence_signal(&fence->base);
dma_fence_put(&fence->base);
}
if (!list_empty(&gt->tlb_invalidation.pending_fences))
queue_delayed_work(system_wq,
&gt->tlb_invalidation.fence_tdr,
TLB_TIMEOUT);
spin_unlock_irq(&gt->tlb_invalidation.pending_lock);
}
/**
* xe_gt_tlb_invalidation_init - Initialize GT TLB invalidation state
* @gt: graphics tile
*
* Initialize GT TLB invalidation state, purely software initialization, should
* be called once during driver load.
*
* Return: 0 on success, negative error code on error.
*/
int xe_gt_tlb_invalidation_init(struct xe_gt *gt)
{
gt->tlb_invalidation.seqno = 1;
INIT_LIST_HEAD(&gt->tlb_invalidation.pending_fences);
spin_lock_init(&gt->tlb_invalidation.pending_lock);
spin_lock_init(&gt->tlb_invalidation.lock);
gt->tlb_invalidation.fence_context = dma_fence_context_alloc(1);
INIT_DELAYED_WORK(&gt->tlb_invalidation.fence_tdr,
xe_gt_tlb_fence_timeout);
return 0;
}
static void
__invalidation_fence_signal(struct xe_gt_tlb_invalidation_fence *fence)
{
trace_xe_gt_tlb_invalidation_fence_signal(fence);
dma_fence_signal(&fence->base);
dma_fence_put(&fence->base);
}
static void
invalidation_fence_signal(struct xe_gt_tlb_invalidation_fence *fence)
{
list_del(&fence->link);
__invalidation_fence_signal(fence);
}
/**
* xe_gt_tlb_invalidation_reset - Initialize GT TLB invalidation reset
* @gt: graphics tile
*
* Signal any pending invalidation fences, should be called during a GT reset
*/
void xe_gt_tlb_invalidation_reset(struct xe_gt *gt)
{
struct xe_gt_tlb_invalidation_fence *fence, *next;
struct xe_guc *guc = &gt->uc.guc;
int pending_seqno;
/*
* CT channel is already disabled at this point. No new TLB requests can
* appear.
*/
mutex_lock(&gt->uc.guc.ct.lock);
spin_lock_irq(&gt->tlb_invalidation.pending_lock);
cancel_delayed_work(&gt->tlb_invalidation.fence_tdr);
/*
* We might have various kworkers waiting for TLB flushes to complete
* which are not tracked with an explicit TLB fence, however at this
* stage that will never happen since the CT is already disabled, so
* make sure we signal them here under the assumption that we have
* completed a full GT reset.
*/
if (gt->tlb_invalidation.seqno == 1)
pending_seqno = TLB_INVALIDATION_SEQNO_MAX - 1;
else
pending_seqno = gt->tlb_invalidation.seqno - 1;
WRITE_ONCE(gt->tlb_invalidation.seqno_recv, pending_seqno);
wake_up_all(&guc->ct.wq);
list_for_each_entry_safe(fence, next,
&gt->tlb_invalidation.pending_fences, link)
invalidation_fence_signal(fence);
spin_unlock_irq(&gt->tlb_invalidation.pending_lock);
mutex_unlock(&gt->uc.guc.ct.lock);
}
static bool tlb_invalidation_seqno_past(struct xe_gt *gt, int seqno)
{
int seqno_recv = READ_ONCE(gt->tlb_invalidation.seqno_recv);
if (seqno - seqno_recv < -(TLB_INVALIDATION_SEQNO_MAX / 2))
return false;
if (seqno - seqno_recv > (TLB_INVALIDATION_SEQNO_MAX / 2))
return true;
return seqno_recv >= seqno;
}
static int send_tlb_invalidation(struct xe_guc *guc,
struct xe_gt_tlb_invalidation_fence *fence,
u32 *action, int len)
{
struct xe_gt *gt = guc_to_gt(guc);
int seqno;
int ret;
/*
* XXX: The seqno algorithm relies on TLB invalidation being processed
* in order which they currently are, if that changes the algorithm will
* need to be updated.
*/
mutex_lock(&guc->ct.lock);
seqno = gt->tlb_invalidation.seqno;
if (fence) {
fence->seqno = seqno;
trace_xe_gt_tlb_invalidation_fence_send(fence);
}
action[1] = seqno;
ret = xe_guc_ct_send_locked(&guc->ct, action, len,
G2H_LEN_DW_TLB_INVALIDATE, 1);
if (!ret && fence) {
spin_lock_irq(&gt->tlb_invalidation.pending_lock);
/*
* We haven't actually published the TLB fence as per
* pending_fences, but in theory our seqno could have already
* been written as we acquired the pending_lock. In such a case
* we can just go ahead and signal the fence here.
*/
if (tlb_invalidation_seqno_past(gt, seqno)) {
__invalidation_fence_signal(fence);
} else {
fence->invalidation_time = ktime_get();
list_add_tail(&fence->link,
&gt->tlb_invalidation.pending_fences);
if (list_is_singular(&gt->tlb_invalidation.pending_fences))
queue_delayed_work(system_wq,
&gt->tlb_invalidation.fence_tdr,
TLB_TIMEOUT);
}
spin_unlock_irq(&gt->tlb_invalidation.pending_lock);
} else if (ret < 0 && fence) {
__invalidation_fence_signal(fence);
}
if (!ret) {
gt->tlb_invalidation.seqno = (gt->tlb_invalidation.seqno + 1) %
TLB_INVALIDATION_SEQNO_MAX;
if (!gt->tlb_invalidation.seqno)
gt->tlb_invalidation.seqno = 1;
ret = seqno;
}
mutex_unlock(&guc->ct.lock);
return ret;
}
#define MAKE_INVAL_OP(type) ((type << XE_GUC_TLB_INVAL_TYPE_SHIFT) | \
XE_GUC_TLB_INVAL_MODE_HEAVY << XE_GUC_TLB_INVAL_MODE_SHIFT | \
XE_GUC_TLB_INVAL_FLUSH_CACHE)
/**
* xe_gt_tlb_invalidation_guc - Issue a TLB invalidation on this GT for the GuC
* @gt: graphics tile
*
* Issue a TLB invalidation for the GuC. Completion of TLB is asynchronous and
* caller can use seqno + xe_gt_tlb_invalidation_wait to wait for completion.
*
* Return: Seqno which can be passed to xe_gt_tlb_invalidation_wait on success,
* negative error code on error.
*/
int xe_gt_tlb_invalidation_guc(struct xe_gt *gt)
{
u32 action[] = {
XE_GUC_ACTION_TLB_INVALIDATION,
0, /* seqno, replaced in send_tlb_invalidation */
MAKE_INVAL_OP(XE_GUC_TLB_INVAL_GUC),
};
return send_tlb_invalidation(&gt->uc.guc, NULL, action,
ARRAY_SIZE(action));
}
/**
* xe_gt_tlb_invalidation_vma - Issue a TLB invalidation on this GT for a VMA
* @gt: graphics tile
* @fence: invalidation fence which will be signal on TLB invalidation
* completion, can be NULL
* @vma: VMA to invalidate
*
* Issue a range based TLB invalidation if supported, if not fallback to a full
* TLB invalidation. Completion of TLB is asynchronous and caller can either use
* the invalidation fence or seqno + xe_gt_tlb_invalidation_wait to wait for
* completion.
*
* Return: Seqno which can be passed to xe_gt_tlb_invalidation_wait on success,
* negative error code on error.
*/
int xe_gt_tlb_invalidation_vma(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence,
struct xe_vma *vma)
{
struct xe_device *xe = gt_to_xe(gt);
#define MAX_TLB_INVALIDATION_LEN 7
u32 action[MAX_TLB_INVALIDATION_LEN];
int len = 0;
xe_gt_assert(gt, vma);
/* Execlists not supported */
if (gt_to_xe(gt)->info.force_execlist) {
if (fence)
__invalidation_fence_signal(fence);
return 0;
}
action[len++] = XE_GUC_ACTION_TLB_INVALIDATION;
action[len++] = 0; /* seqno, replaced in send_tlb_invalidation */
if (!xe->info.has_range_tlb_invalidation) {
action[len++] = MAKE_INVAL_OP(XE_GUC_TLB_INVAL_FULL);
} else {
u64 start = xe_vma_start(vma);
u64 length = xe_vma_size(vma);
u64 align, end;
if (length < SZ_4K)
length = SZ_4K;
/*
* We need to invalidate a higher granularity if start address
* is not aligned to length. When start is not aligned with
* length we need to find the length large enough to create an
* address mask covering the required range.
*/
align = roundup_pow_of_two(length);
start = ALIGN_DOWN(xe_vma_start(vma), align);
end = ALIGN(xe_vma_end(vma), align);
length = align;
while (start + length < end) {
length <<= 1;
start = ALIGN_DOWN(xe_vma_start(vma), length);
}
/*
* Minimum invalidation size for a 2MB page that the hardware
* expects is 16MB
*/
if (length >= SZ_2M) {
length = max_t(u64, SZ_16M, length);
start = ALIGN_DOWN(xe_vma_start(vma), length);
}
xe_gt_assert(gt, length >= SZ_4K);
xe_gt_assert(gt, is_power_of_2(length));
xe_gt_assert(gt, !(length & GENMASK(ilog2(SZ_16M) - 1, ilog2(SZ_2M) + 1)));
xe_gt_assert(gt, IS_ALIGNED(start, length));
action[len++] = MAKE_INVAL_OP(XE_GUC_TLB_INVAL_PAGE_SELECTIVE);
action[len++] = xe_vma_vm(vma)->usm.asid;
action[len++] = lower_32_bits(start);
action[len++] = upper_32_bits(start);
action[len++] = ilog2(length) - ilog2(SZ_4K);
}
xe_gt_assert(gt, len <= MAX_TLB_INVALIDATION_LEN);
return send_tlb_invalidation(&gt->uc.guc, fence, action, len);
}
/**
* xe_gt_tlb_invalidation_wait - Wait for TLB to complete
* @gt: graphics tile
* @seqno: seqno to wait which was returned from xe_gt_tlb_invalidation
*
* Wait for 200ms for a TLB invalidation to complete, in practice we always
* should receive the TLB invalidation within 200ms.
*
* Return: 0 on success, -ETIME on TLB invalidation timeout
*/
int xe_gt_tlb_invalidation_wait(struct xe_gt *gt, int seqno)
{
struct xe_guc *guc = &gt->uc.guc;
int ret;
/* Execlists not supported */
if (gt_to_xe(gt)->info.force_execlist)
return 0;
/*
* XXX: See above, this algorithm only works if seqno are always in
* order
*/
ret = wait_event_timeout(guc->ct.wq,
tlb_invalidation_seqno_past(gt, seqno),
TLB_TIMEOUT);
if (!ret) {
struct drm_printer p = xe_gt_err_printer(gt);
xe_gt_err(gt, "TLB invalidation time'd out, seqno=%d, recv=%d\n",
seqno, gt->tlb_invalidation.seqno_recv);
xe_guc_ct_print(&guc->ct, &p, true);
return -ETIME;
}
return 0;
}
/**
* xe_guc_tlb_invalidation_done_handler - TLB invalidation done handler
* @guc: guc
* @msg: message indicating TLB invalidation done
* @len: length of message
*
* Parse seqno of TLB invalidation, wake any waiters for seqno, and signal any
* invalidation fences for seqno. Algorithm for this depends on seqno being
* received in-order and asserts this assumption.
*
* Return: 0 on success, -EPROTO for malformed messages.
*/
int xe_guc_tlb_invalidation_done_handler(struct xe_guc *guc, u32 *msg, u32 len)
{
struct xe_gt *gt = guc_to_gt(guc);
struct xe_gt_tlb_invalidation_fence *fence, *next;
unsigned long flags;
if (unlikely(len != 1))
return -EPROTO;
/*
* This can also be run both directly from the IRQ handler and also in
* process_g2h_msg(). Only one may process any individual CT message,
* however the order they are processed here could result in skipping a
* seqno. To handle that we just process all the seqnos from the last
* seqno_recv up to and including the one in msg[0]. The delta should be
* very small so there shouldn't be much of pending_fences we actually
* need to iterate over here.
*
* From GuC POV we expect the seqnos to always appear in-order, so if we
* see something later in the timeline we can be sure that anything
* appearing earlier has already signalled, just that we have yet to
* officially process the CT message like if racing against
* process_g2h_msg().
*/
spin_lock_irqsave(&gt->tlb_invalidation.pending_lock, flags);
if (tlb_invalidation_seqno_past(gt, msg[0])) {
spin_unlock_irqrestore(&gt->tlb_invalidation.pending_lock, flags);
return 0;
}
/*
* wake_up_all() and wait_event_timeout() already have the correct
* barriers.
*/
WRITE_ONCE(gt->tlb_invalidation.seqno_recv, msg[0]);
wake_up_all(&guc->ct.wq);
list_for_each_entry_safe(fence, next,
&gt->tlb_invalidation.pending_fences, link) {
trace_xe_gt_tlb_invalidation_fence_recv(fence);
if (!tlb_invalidation_seqno_past(gt, fence->seqno))
break;
invalidation_fence_signal(fence);
}
if (!list_empty(&gt->tlb_invalidation.pending_fences))
mod_delayed_work(system_wq,
&gt->tlb_invalidation.fence_tdr,
TLB_TIMEOUT);
else
cancel_delayed_work(&gt->tlb_invalidation.fence_tdr);
spin_unlock_irqrestore(&gt->tlb_invalidation.pending_lock, flags);
return 0;
}