drivers: mailbox: qti_tcs: Add count stats for debug
Add counters to record number of requests sent and the IRQ responses
received for the requests to provide more debug information.
Also instead of calling BUG(), WARN() since a lot of false positives
show up.
Change-Id: I510136b6d3d3c2e277d5387cac95428f72683a23
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
diff --git a/drivers/mailbox/qti-tcs.c b/drivers/mailbox/qti-tcs.c
index 96b4472..fb97a6c 100644
--- a/drivers/mailbox/qti-tcs.c
+++ b/drivers/mailbox/qti-tcs.c
@@ -135,7 +135,9 @@
int num_tcs;
struct workqueue_struct *wq;
struct tcs_response_pool *resp_pool;
- atomic_t tcs_in_use[TCS_TYPE_NR * MAX_TCS_PER_TYPE];
+ atomic_t tcs_in_use[MAX_POOL_SIZE];
+ atomic_t tcs_send_count[MAX_POOL_SIZE];
+ atomic_t tcs_irq_count[MAX_POOL_SIZE];
};
static void tcs_notify_tx_done(unsigned long data);
@@ -361,6 +363,8 @@
if (!(irq_status & BIT(m)))
continue;
+ atomic_inc(&drv->tcs_irq_count[m]);
+
resp = get_response(drv, m);
if (!resp) {
pr_err("No resp request for TCS-%d\n", m);
@@ -457,16 +461,20 @@
struct tcs_mbox_msg *msg = resp->msg;
struct tcs_drv *drv = resp->drv;
int m = resp->m;
+ u32 irq_status;
+ struct tcs_mbox *tcs = get_tcs_from_index(drv, m);
+ bool pending = false;
+ int sent_count, irq_count;
+ int i;
- /*
- * In case the RPMH resource fails to respond to the completion
- * request, the TCS would be blocked forever waiting on the response.
- * There is no way to recover from this case.
- */
+ /* Read while holding a lock, to get a consistent state snapshot */
+ spin_lock(&tcs->tcs_lock);
+ irq_status = read_tcs_reg(drv->reg_base, TCS_DRV_IRQ_STATUS, 0, 0);
+ sent_count = atomic_read(&drv->tcs_send_count[m]);
+ irq_count = atomic_read(&drv->tcs_irq_count[m]);
+
if (!tcs_is_free(drv, m)) {
- bool pending = false;
struct tcs_cmd *cmd;
- int i;
u32 addr;
for (i = 0; i < msg->num_payload; i++) {
@@ -475,15 +483,39 @@
m, i);
pending |= (cmd->addr == addr);
}
- if (pending) {
- pr_err("TCS-%d blocked waiting for RPMH to respond.\n",
- m);
- for (i = 0; i < msg->num_payload; i++)
- pr_err("Addr: 0x%x Data: 0x%x\n",
- msg->payload[i].addr,
- msg->payload[i].data);
- BUG();
- }
+ }
+ spin_unlock(&tcs->tcs_lock);
+
+ if (pending) {
+ pr_err("TCS-%d waiting for response. (sent=%d recvd=%d ctrlr-sts=0x%x)\n",
+ m, sent_count, irq_count, irq_status & (u32)BIT(m));
+ for (i = 0; i < msg->num_payload; i++)
+ pr_err("Addr: 0x%x Data: 0x%x\n",
+ msg->payload[i].addr,
+ msg->payload[i].data);
+ /*
+ * In case the RPMH resource fails to respond to the
+ * completion request, the TCS would be blocked forever
+ * waiting on the response. There is no way to recover
+ * from such a case. But WARN() to investigate any false
+ * positives.
+ */
+ WARN_ON(irq_status & BIT(m));
+
+ /* Clear the TCS status register so we could try again */
+ write_tcs_reg(drv->reg_base, TCS_DRV_IRQ_CLEAR, 0, 0, BIT(m));
+
+ /* Increment the response count, so it doesn't keep adding up */
+ atomic_inc(&drv->tcs_irq_count[m]);
+
+ /*
+ * If the request was fire-n-forget then the controller,
+ * then our controller is OK, but the accelerator may be
+ * in a bad state.
+ * Let the upper layers figure out what needs to be done
+ * in such a case. Return error code and carry on.
+ */
+ atomic_set(&drv->tcs_in_use[m], 0);
}
mbox_notify_tx_done(chan, msg, -1, -ETIMEDOUT);
@@ -717,6 +749,7 @@
resp->m = m;
/* Mark the TCS as busy */
atomic_set(&drv->tcs_in_use[m], 1);
+ atomic_inc(&drv->tcs_send_count[m]);
wait_for_req_inflight(drv, tcs, msg);
}