1 files changed, 20 insertions, 14 deletions

diff --git a/drivers/media/video/cx18/cx18-mailbox.c b/drivers/media/video/cx18/cx18-mailbox.c
index d49c7c27c18f..844a62de6535 100644
--- a/drivers/media/video/cx18/cx18-mailbox.c
+++ b/drivers/media/video/cx18/cx18-mailbox.c
@@ -233,7 +233,7 @@ void cx18_epu_work_handler(struct work_struct *work)
  * Functions that run in an interrupt handling context
  */
 
-static void mb_ack_irq(struct cx18 *cx, const struct cx18_epu_work_order *order)
+static void mb_ack_irq(struct cx18 *cx, struct cx18_epu_work_order *order)
 {
         struct cx18_mailbox __iomem *ack_mb;
         u32 ack_irq, req;
@@ -256,15 +256,20 @@ static void mb_ack_irq(struct cx18 *cx, const struct cx18_epu_work_order *order)
         req = order->mb.request;
         /* Don't ack if the RPU has gotten impatient and timed us out */
         if (req != cx18_readl(cx, &ack_mb->request) ||
-            req == cx18_readl(cx, &ack_mb->ack))
+            req == cx18_readl(cx, &ack_mb->ack)) {
+                CX18_WARN("Possibly falling behind: %s self-ack'ed our incoming"
+                          " %s to EPU mailbox (sequence no. %u) while "
+                          "processing\n",
+                          rpu_str[order->rpu], rpu_str[order->rpu], req);
+                order->flags |= CX18_F_EWO_MB_STALE_WHILE_PROC;
                 return;
+        }
         cx18_writel(cx, req, &ack_mb->ack);
         cx18_write_reg_expect(cx, ack_irq, SW2_INT_SET, ack_irq, ack_irq);
         return;
 }
 
-static int epu_dma_done_irq(struct cx18 *cx, struct cx18_epu_work_order *order,
-                            int stale)
+static int epu_dma_done_irq(struct cx18 *cx, struct cx18_epu_work_order *order)
 {
         u32 handle, mdl_ack_offset, mdl_ack_count;
         struct cx18_mailbox *mb;
@@ -276,20 +281,21 @@ static int epu_dma_done_irq(struct cx18 *cx, struct cx18_epu_work_order *order,
 
         if (handle == CX18_INVALID_TASK_HANDLE ||
             mdl_ack_count == 0 || mdl_ack_count > CX18_MAX_MDL_ACKS) {
-                if (!stale)
+                if ((order->flags & CX18_F_EWO_MB_STALE) == 0)
                         mb_ack_irq(cx, order);
                 return -1;
         }
 
         cx18_memcpy_fromio(cx, order->mdl_ack, cx->enc_mem + mdl_ack_offset,
                            sizeof(struct cx18_mdl_ack) * mdl_ack_count);
-        if (!stale)
+
+        if ((order->flags & CX18_F_EWO_MB_STALE) == 0)
                 mb_ack_irq(cx, order);
         return 1;
 }
 
 static
-int epu_debug_irq(struct cx18 *cx, struct cx18_epu_work_order *order, int stale)
+int epu_debug_irq(struct cx18 *cx, struct cx18_epu_work_order *order)
 {
         u32 str_offset;
         char *str = order->str;
@@ -303,14 +309,14 @@ int epu_debug_irq(struct cx18 *cx, struct cx18_epu_work_order *order, int stale)
                 cx18_setup_page(cx, SCB_OFFSET);
         }
 
-        if (!stale)
+        if ((order->flags & CX18_F_EWO_MB_STALE) == 0)
                 mb_ack_irq(cx, order);
 
         return str_offset ? 1 : 0;
 }
 
 static inline
-int epu_cmd_irq(struct cx18 *cx, struct cx18_epu_work_order *order, int stale)
+int epu_cmd_irq(struct cx18 *cx, struct cx18_epu_work_order *order)
 {
         int ret = -1;
 
@@ -319,10 +325,10 @@ int epu_cmd_irq(struct cx18 *cx, struct cx18_epu_work_order *order, int stale)
         {
                 switch (order->mb.cmd) {
                 case CX18_EPU_DMA_DONE:
-                        ret = epu_dma_done_irq(cx, order, stale);
+                        ret = epu_dma_done_irq(cx, order);
                         break;
                 case CX18_EPU_DEBUG:
-                        ret = epu_debug_irq(cx, order, stale);
+                        ret = epu_debug_irq(cx, order);
                         break;
                 default:
                         CX18_WARN("Unknown CPU to EPU mailbox command %#0x\n",
@@ -370,7 +376,6 @@ void cx18_api_epu_cmd_irq(struct cx18 *cx, int rpu)
         struct cx18_mailbox __iomem *mb;
         struct cx18_mailbox *order_mb;
         struct cx18_epu_work_order *order;
-        int stale = 0;
         int submit;
 
         switch (rpu) {
@@ -391,6 +396,7 @@ void cx18_api_epu_cmd_irq(struct cx18 *cx, int rpu)
                 return;
         }
 
+        order->flags = 0;
         order->rpu = rpu;
         order_mb = &order->mb;
         cx18_memcpy_fromio(cx, order_mb, mb, sizeof(struct cx18_mailbox));
@@ -400,14 +406,14 @@ void cx18_api_epu_cmd_irq(struct cx18 *cx, int rpu)
                           " %s to EPU mailbox (sequence no. %u)\n",
                           rpu_str[rpu], rpu_str[rpu], order_mb->request);
                 dump_mb(cx, order_mb, "incoming");
-                stale = 1;
+                order->flags = CX18_F_EWO_MB_STALE_UPON_RECEIPT;
         }
 
         /*
          * Individual EPU command processing is responsible for ack-ing
          * a non-stale mailbox as soon as possible
          */
-        submit = epu_cmd_irq(cx, order, stale);
+        submit = epu_cmd_irq(cx, order);
         if (submit > 0) {
                 queue_work(cx18_work_queue, &order->work);
         }