diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.15/950-0352-media-bcm2835-unicam-Fix-bug-in-buffer-swapping-logi.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.15/950-0352-media-bcm2835-unicam-Fix-bug-in-buffer-swapping-logi.patch | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.15/950-0352-media-bcm2835-unicam-Fix-bug-in-buffer-swapping-logi.patch b/target/linux/bcm27xx/patches-5.15/950-0352-media-bcm2835-unicam-Fix-bug-in-buffer-swapping-logi.patch new file mode 100644 index 0000000000..364600158d --- /dev/null +++ b/target/linux/bcm27xx/patches-5.15/950-0352-media-bcm2835-unicam-Fix-bug-in-buffer-swapping-logi.patch @@ -0,0 +1,75 @@ +From e86fdc72907b8cf1aab4dfd70843ffb166de0405 Mon Sep 17 00:00:00 2001 +From: Naushir Patuck <naush@raspberrypi.com> +Date: Fri, 5 Mar 2021 15:40:45 +0000 +Subject: [PATCH] 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 +@@ -798,6 +798,7 @@ 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); +@@ -815,12 +816,18 @@ 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 +@@ -831,7 +838,15 @@ 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; +@@ -868,7 +883,7 @@ 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; |