mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 15:02:32 +00:00
76 lines
2.8 KiB
Diff
76 lines
2.8 KiB
Diff
|
From c262465294d0b15f158518501d3918c52f7c1b22 Mon Sep 17 00:00:00 2001
|
||
|
|
From: Naushir Patuck <naush@raspberrypi.com>
|
||
|
|
Date: Fri, 5 Mar 2021 15:40:45 +0000
|
||
|
|
Subject: [PATCH 0279/1085] media: bcm2835-unicam: Fix bug in buffer swapping
|
||
|
|
logic
|
||
|
|
|
||
|
|
If multiple sets of interrupts occur simultaneously, it may be unsafe
|
||
|
|
to swap buffers, as the hardware may already be re-using the current
|
||
|
|
buffers. In such cases, avoid swapping buffers, and wait for the next
|
||
|
|
opportunity at the Frame End interrupt to signal completion.
|
||
|
|
|
||
|
|
Additionally, check the packet compare status when watching for frame
|
||
|
|
end for buffers swaps, as this could also signify a frame end event.
|
||
|
|
|
||
|
|
Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
|
||
|
|
---
|
||
|
|
.../media/platform/bcm2835/bcm2835-unicam.c | 21 ++++++++++++++++---
|
||
|
|
1 file changed, 18 insertions(+), 3 deletions(-)
|
||
|
|
|
||
|
|
--- a/drivers/media/platform/bcm2835/bcm2835-unicam.c
|
||
|
|
+++ b/drivers/media/platform/bcm2835/bcm2835-unicam.c
|
||
|
|
@@ -800,6 +800,7 @@ static irqreturn_t unicam_isr(int irq, v
|
||
|
|
unsigned int sequence = unicam->sequence;
|
||
|
|
unsigned int i;
|
||
|
|
u32 ista, sta;
|
||
|
|
+ bool fe;
|
||
|
|
u64 ts;
|
||
|
|
|
||
|
|
sta = reg_read(unicam, UNICAM_STA);
|
||
|
|
@@ -817,12 +818,18 @@ static irqreturn_t unicam_isr(int irq, v
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
|
||
|
|
/*
|
||
|
|
+ * Look for either the Frame End interrupt or the Packet Capture status
|
||
|
|
+ * to signal a frame end.
|
||
|
|
+ */
|
||
|
|
+ fe = (ista & UNICAM_FEI || sta & UNICAM_PI0);
|
||
|
|
+
|
||
|
|
+ /*
|
||
|
|
* We must run the frame end handler first. If we have a valid next_frm
|
||
|
|
* and we get a simultaneout FE + FS interrupt, running the FS handler
|
||
|
|
* first would null out the next_frm ptr and we would have lost the
|
||
|
|
* buffer forever.
|
||
|
|
*/
|
||
|
|
- if (ista & UNICAM_FEI || sta & UNICAM_PI0) {
|
||
|
|
+ if (fe) {
|
||
|
|
/*
|
||
|
|
* Ensure we have swapped buffers already as we can't
|
||
|
|
* stop the peripheral. If no buffer is available, use a
|
||
|
|
@@ -833,7 +840,15 @@ static irqreturn_t unicam_isr(int irq, v
|
||
|
|
if (!unicam->node[i].streaming)
|
||
|
|
continue;
|
||
|
|
|
||
|
|
- if (unicam->node[i].cur_frm)
|
||
|
|
+ /*
|
||
|
|
+ * If cur_frm == next_frm, it means we have not had
|
||
|
|
+ * a chance to swap buffers, likely due to having
|
||
|
|
+ * multiple interrupts occurring simultaneously (like FE
|
||
|
|
+ * + FS + LS). In this case, we cannot signal the buffer
|
||
|
|
+ * as complete, as the HW will reuse that buffer.
|
||
|
|
+ */
|
||
|
|
+ if (unicam->node[i].cur_frm &&
|
||
|
|
+ unicam->node[i].cur_frm != unicam->node[i].next_frm)
|
||
|
|
unicam_process_buffer_complete(&unicam->node[i],
|
||
|
|
sequence);
|
||
|
|
unicam->node[i].cur_frm = unicam->node[i].next_frm;
|
||
|
|
@@ -870,7 +885,7 @@ static irqreturn_t unicam_isr(int irq, v
|
||
|
|
* where the HW does not actually swap it if the new frame has
|
||
|
|
* already started.
|
||
|
|
*/
|
||
|
|
- if (ista & (UNICAM_FSI | UNICAM_LCI) && !(ista & UNICAM_FEI)) {
|
||
|
|
+ if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
|
||
|
|
for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
|
||
|
|
if (!unicam->node[i].streaming)
|
||
|
|
continue;
|