{
+ struct guc_ct_buffer_desc *desc = ctb->desc;
CT_DEBUG_DRIVER("CT: desc %p reset head=%u tail=%u\n",
desc, desc->head, desc->tail);
- desc->head = 0;
- desc->tail = 0;
+ ctb->head = desc->head = 0;
+ ctb->tail = desc->tail = 0;
+ ctb->space = CIRC_SPACE(ctb->tail, ctb->head, ctb->size);
desc->is_in_error = 0;
}
@@ -220,7 +226,7 @@ static int ctch_enable(struct intel_guc *guc,
*/
for (i = 0; i < ARRAY_SIZE(ctch->ctbs); i++) {
GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV));
- guc_ct_buffer_desc_init(ctch->ctbs[i].desc,
+ guc_ct_buffer_desc_init(&ctch->ctbs[i],
base + PAGE_SIZE/4 * i + PAGE_SIZE/2,
PAGE_SIZE/4,
ctch->owner);
@@ -301,32 +307,16 @@ static int ctb_write(struct
intel_guc_ct_buffer *ctb,
bool want_response)
{
struct guc_ct_buffer_desc *desc = ctb->desc;
- u32 head = desc->head / 4; /* in dwords */
- u32 tail = desc->tail / 4; /* in dwords */
- u32 size = desc->size / 4; /* in dwords */
- u32 used; /* in dwords */
+ u32 tail = ctb->tail / 4; /* in dwords */
+ u32 size = ctb->size / 4; /* in dwords */
u32 header;
u32 *cmds = ctb->cmds;
unsigned int i;
- GEM_BUG_ON(desc->size % 4);
- GEM_BUG_ON(desc->head % 4);
- GEM_BUG_ON(desc->tail % 4);
+ GEM_BUG_ON(ctb->size % 4);
+ GEM_BUG_ON(ctb->tail % 4);
GEM_BUG_ON(tail >= size);
- /*
- * tail == head condition indicates empty. GuC FW does not support
- * using up the entire buffer to get tail == head meaning full.
- */
- if (tail < head)
- used = (size - head) + tail;
- else
- used = tail - head;
-
- /* make sure there is a space including extra dw for the fence */
- if (unlikely(used + len + 1 >= size))
- return -ENOSPC;
-
/*
* Write the message. The format is the following:
* DW0: header (including action code)
@@ -354,15 +344,16 @@ static int ctb_write(struct
intel_guc_ct_buffer *ctb,
}
/* now update desc tail (back in bytes) */
- desc->tail = tail * 4;
- GEM_BUG_ON(desc->tail > desc->size);
+ ctb->tail = desc->tail = tail * 4;
+ ctb->space -= (len + 1) * 4;
+ GEM_BUG_ON(ctb->tail > ctb->size);
return 0;
}
/**
* wait_for_ctb_desc_update - Wait for the CT buffer descriptor update.
- * @desc: buffer descriptor
+ * @ctb: ctb buffer
* @fence: response fence
* @status: placeholder for status
*
@@ -376,11 +367,12 @@ static int ctb_write(struct
intel_guc_ct_buffer *ctb,
* * -ETIMEDOUT no response within hardcoded timeout
* * -EPROTO no response, CT buffer is in error
*/
-static int wait_for_ctb_desc_update(struct guc_ct_buffer_desc *desc,
+static int wait_for_ctb_desc_update(struct intel_guc_ct_buffer *ctb,
u32 fence,
u32 *status)
{
int err;
+ struct guc_ct_buffer_desc *desc = ctb->desc;
/*
* Fast commands should complete in less than 10us, so sample quickly
@@ -401,7 +393,7 @@ static int wait_for_ctb_desc_update(struct
guc_ct_buffer_desc *desc,
/* Something went wrong with the messaging, try to reset
* the buffer and hope for the best
*/
- guc_ct_buffer_desc_reset(desc);
+ guc_ct_buffer_desc_reset(ctb);
err = -EPROTO;
}
}
@@ -446,12 +438,17 @@ static int wait_for_ct_request_update(struct
ct_request *req, u32 *status)
return err;
}
-static inline bool ctb_has_room(struct guc_ct_buffer_desc *desc,
u32 len)
+static inline bool ctb_has_room(struct intel_guc_ct_buffer *ctb,
u32 len)
{
- u32 head = READ_ONCE(desc->head);
+ u32 head;
u32 space;
- space = CIRC_SPACE(desc->tail, head, desc->size);
+ if (ctb->space >= len)
+ return true;
+
+ head = READ_ONCE(ctb->desc->head);
+ space = CIRC_SPACE(ctb->tail, head, ctb->size);
+ ctb->space = space;
return space >= len;
}
@@ -462,7 +459,6 @@ int intel_guc_send_nb(struct intel_guc_ct *ct,
{
struct intel_guc_ct_channel *ctch = &ct->host_channel;
struct intel_guc_ct_buffer *ctb = &ctch->ctbs[CTB_SEND];
- struct guc_ct_buffer_desc *desc = ctb->desc;
int err;
GEM_BUG_ON(!ctch->enabled);
@@ -470,7 +466,7 @@ int intel_guc_send_nb(struct intel_guc_ct *ct,
GEM_BUG_ON(len & ~GUC_CT_MSG_LEN_MASK);
lockdep_assert_held(&ct->send_lock);
- if (unlikely(!ctb_has_room(desc, (len + 1) * 4))) {
+ if (unlikely(!ctb_has_room(ctb, (len + 1) * 4))) {
ct->retry++;
if (ct->retry >= MAX_RETRY)
return -EDEADLK;
@@ -496,7 +492,6 @@ static int ctch_send(struct intel_guc_ct *ct,
u32 *status)
{
struct intel_guc_ct_buffer *ctb = &ctch->ctbs[CTB_SEND];
- struct guc_ct_buffer_desc *desc = ctb->desc;
struct ct_request request;
unsigned long flags;
u32 fence;
@@ -514,7 +509,7 @@ static int ctch_send(struct intel_guc_ct *ct,
*/
retry:
spin_lock_irqsave(&ct->send_lock, flags);
- if (unlikely(!ctb_has_room(desc, (len + 1) * 4))) {
+ if (unlikely(!ctb_has_room(ctb, (len + 1) * 4))) {
spin_unlock_irqrestore(&ct->send_lock, flags);
ct->retry++;
if (ct->retry >= MAX_RETRY)
@@ -544,7 +539,7 @@ static int ctch_send(struct intel_guc_ct *ct,
if (response_buf)
err = wait_for_ct_request_update(&request, status);
else
- err = wait_for_ctb_desc_update(desc, fence, status);
+ err = wait_for_ctb_desc_update(ctb, fence, status);
if (unlikely(err))
goto unlink;
@@ -618,9 +613,9 @@ static inline bool ct_header_is_response(u32 header)
static int ctb_read(struct intel_guc_ct_buffer *ctb, u32 *data)
{
struct guc_ct_buffer_desc *desc = ctb->desc;
- u32 head = desc->head / 4; /* in dwords */
+ u32 head = ctb->head / 4; /* in dwords */
u32 tail = desc->tail / 4; /* in dwords */
- u32 size = desc->size / 4; /* in dwords */
+ u32 size = ctb->size / 4; /* in dwords */
u32 *cmds = ctb->cmds;
s32 available; /* in dwords */
unsigned int len;
@@ -664,7 +659,7 @@ static int ctb_read(struct intel_guc_ct_buffer
*ctb, u32 *data)
}
CT_DEBUG_DRIVER("CT: received %*ph\n", 4 * len, data);
- desc->head = head * 4;
+ ctb->head = desc->head = head * 4;
return 0;
}
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
index bc670a796bd8..1bff4f0b91f7 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
@@ -29,10 +29,18 @@ struct intel_guc;
*
* @desc: pointer to the buffer descriptor
* @cmds: pointer to the commands buffer
+ * @size: local shadow copy of size
