[ Upstream commit 9698ed4d4a2993ce54b9f7d71a2891e972caa117 ]
Video engine clock control can be double disabled and eventually it causes a kernel warning with stack dump printing out like below:
[ 515.540498] ------------[ cut here ]------------ [ 515.545174] WARNING: CPU: 0 PID: 1310 at drivers/clk/clk.c:684 clk_core_unprepare+0x13c/0x170 [ 515.553806] vclk-gate already unprepared [ 515.557841] CPU: 0 PID: 1310 Comm: obmc-ikvm Tainted: G W 5.0.6-df66fbc97853fbba90a0bfa44de32f3d5f7602b4 #1 [ 515.568973] Hardware name: Generic DT based system [ 515.573777] Backtrace: [ 515.576272] [<80107cdc>] (dump_backtrace) from [<80107f10>] (show_stack+0x20/0x24) [ 515.583930] r7:803a5614 r6:00000009 r5:00000000 r4:9d88fe1c [ 515.589712] [<80107ef0>] (show_stack) from [<80690184>] (dump_stack+0x20/0x28) [ 515.597053] [<80690164>] (dump_stack) from [<80116044>] (__warn.part.3+0xb4/0xdc) [ 515.604557] [<80115f90>] (__warn.part.3) from [<801160d8>] (warn_slowpath_fmt+0x6c/0x90) [ 515.612734] r6:000002ac r5:8080befc r4:80a07008 [ 515.617463] [<80116070>] (warn_slowpath_fmt) from [<803a5614>] (clk_core_unprepare+0x13c/0x170) [ 515.626167] r3:8080cdf4 r2:8080bfc0 [ 515.629834] r7:98d682a8 r6:9d8a9200 r5:9e5151a0 r4:97abd620 [ 515.635530] [<803a54d8>] (clk_core_unprepare) from [<803a76a4>] (clk_unprepare+0x34/0x3c) [ 515.643812] r5:9e5151a0 r4:97abd620 [ 515.647529] [<803a7670>] (clk_unprepare) from [<804f36ec>] (aspeed_video_off+0x38/0x50) [ 515.655539] r5:9e5151a0 r4:9e504000 [ 515.659242] [<804f36b4>] (aspeed_video_off) from [<804f4358>] (aspeed_video_release+0x90/0x114) [ 515.668036] r5:9e5044b0 r4:9e504000 [ 515.671643] [<804f42c8>] (aspeed_video_release) from [<804d302c>] (v4l2_release+0xd4/0xe8) [ 515.679999] r7:98d682a8 r6:9d087810 r5:9d8a9200 r4:9e504318 [ 515.685695] [<804d2f58>] (v4l2_release) from [<80236454>] (__fput+0x98/0x1c4) [ 515.692914] r5:9e51b608 r4:9d8a9200 [ 515.696597] [<802363bc>] (__fput) from [<802365e8>] (____fput+0x18/0x1c) [ 515.703315] r9:80a0700c r8:801011e4 r7:00000000 r6:80a64b9c r5:9d8e35a0 r4:9d8e38dc [ 515.711167] [<802365d0>] (____fput) from [<80131ca4>] (task_work_run+0x7c/0xa0) [ 515.718596] [<80131c28>] (task_work_run) from [<80106884>] (do_work_pending+0x4a8/0x578) [ 515.726777] r7:801011e4 r6:80a07008 r5:9d88ffb0 r4:ffffe000 [ 515.732466] [<801063dc>] (do_work_pending) from [<8010106c>] (slow_work_pending+0xc/0x20) [ 515.740727] Exception stack(0x9d88ffb0 to 0x9d88fff8) [ 515.745840] ffa0: 00000000 76f18094 00000000 00000000 [ 515.754122] ffc0: 00000007 00176778 7eda4c20 00000006 00000000 00000000 48e20fa4 00000000 [ 515.762386] ffe0: 00000002 7eda4b08 00000000 48f91efc 80000010 00000007 [ 515.769097] r10:00000000 r9:9d88e000 r8:801011e4 r7:00000006 r6:7eda4c20 r5:00176778 [ 515.777006] r4:00000007 [ 515.779558] ---[ end trace 12c04aadef8afbbb ]--- [ 515.784176] ------------[ cut here ]------------ [ 515.788817] WARNING: CPU: 0 PID: 1310 at drivers/clk/clk.c:825 clk_core_disable+0x18c/0x204 [ 515.797161] eclk-gate already disabled [ 515.800916] CPU: 0 PID: 1310 Comm: obmc-ikvm Tainted: G W 5.0.6-df66fbc97853fbba90a0bfa44de32f3d5f7602b4 #1 [ 515.811945] Hardware name: Generic DT based system [ 515.816730] Backtrace: [ 515.819210] [<80107cdc>] (dump_backtrace) from [<80107f10>] (show_stack+0x20/0x24) [ 515.826782] r7:803a5900 r6:00000009 r5:00000000 r4:9d88fe04 [ 515.832454] [<80107ef0>] (show_stack) from [<80690184>] (dump_stack+0x20/0x28) [ 515.839687] [<80690164>] (dump_stack) from [<80116044>] (__warn.part.3+0xb4/0xdc) [ 515.847170] [<80115f90>] (__warn.part.3) from [<801160d8>] (warn_slowpath_fmt+0x6c/0x90) [ 515.855247] r6:00000339 r5:8080befc r4:80a07008 [ 515.859868] [<80116070>] (warn_slowpath_fmt) from [<803a5900>] (clk_core_disable+0x18c/0x204) [ 515.868385] r3:8080cdd0 r2:8080c00c [ 515.871957] r7:98d682a8 r6:9d8a9200 r5:97abd560 r4:97abd560 [ 515.877615] [<803a5774>] (clk_core_disable) from [<803a59a0>] (clk_core_disable_lock+0x28/0x34) [ 515.886301] r7:98d682a8 r6:9d8a9200 r5:97abd560 r4:a0000013 [ 515.891960] [<803a5978>] (clk_core_disable_lock) from [<803a7714>] (clk_disable+0x2c/0x30) [ 515.900216] r5:9e5151a0 r4:9e515f60 [ 515.903816] [<803a76e8>] (clk_disable) from [<804f36f8>] (aspeed_video_off+0x44/0x50) [ 515.911656] [<804f36b4>] (aspeed_video_off) from [<804f4358>] (aspeed_video_release+0x90/0x114) [ 515.920341] r5:9e5044b0 r4:9e504000 [ 515.923921] [<804f42c8>] (aspeed_video_release) from [<804d302c>] (v4l2_release+0xd4/0xe8) [ 515.932184] r7:98d682a8 r6:9d087810 r5:9d8a9200 r4:9e504318 [ 515.937851] [<804d2f58>] (v4l2_release) from [<80236454>] (__fput+0x98/0x1c4) [ 515.944980] r5:9e51b608 r4:9d8a9200 [ 515.948559] [<802363bc>] (__fput) from [<802365e8>] (____fput+0x18/0x1c) [ 515.955257] r9:80a0700c r8:801011e4 r7:00000000 r6:80a64b9c r5:9d8e35a0 r4:9d8e38dc [ 515.963008] [<802365d0>] (____fput) from [<80131ca4>] (task_work_run+0x7c/0xa0) [ 515.970333] [<80131c28>] (task_work_run) from [<80106884>] (do_work_pending+0x4a8/0x578) [ 515.978421] r7:801011e4 r6:80a07008 r5:9d88ffb0 r4:ffffe000 [ 515.984086] [<801063dc>] (do_work_pending) from [<8010106c>] (slow_work_pending+0xc/0x20) [ 515.992247] Exception stack(0x9d88ffb0 to 0x9d88fff8) [ 515.997296] ffa0: 00000000 76f18094 00000000 00000000 [ 516.005473] ffc0: 00000007 00176778 7eda4c20 00000006 00000000 00000000 48e20fa4 00000000 [ 516.013642] ffe0: 00000002 7eda4b08 00000000 48f91efc 80000010 00000007 [ 516.020257] r10:00000000 r9:9d88e000 r8:801011e4 r7:00000006 r6:7eda4c20 r5:00176778 [ 516.028072] r4:00000007 [ 516.030606] ---[ end trace 12c04aadef8afbbc ]---
To prevent this issue, this commit adds clock status checking logic into the Aspeed video engine driver.
Signed-off-by: Jae Hyun Yoo jae.hyun.yoo@linux.intel.com Reviewed-by: Eddie James eajames@linux.ibm.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/platform/aspeed-video.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c index 76d7512c82a3..de0f192afa8b 100644 --- a/drivers/media/platform/aspeed-video.c +++ b/drivers/media/platform/aspeed-video.c @@ -187,6 +187,7 @@ enum { VIDEO_STREAMING, VIDEO_FRAME_INPRG, VIDEO_STOPPED, + VIDEO_CLOCKS_ON, };
struct aspeed_video_addr { @@ -483,19 +484,29 @@ static void aspeed_video_enable_mode_detect(struct aspeed_video *video)
static void aspeed_video_off(struct aspeed_video *video) { + if (!test_bit(VIDEO_CLOCKS_ON, &video->flags)) + return; + /* Disable interrupts */ aspeed_video_write(video, VE_INTERRUPT_CTRL, 0);
/* Turn off the relevant clocks */ clk_disable_unprepare(video->vclk); clk_disable_unprepare(video->eclk); + + clear_bit(VIDEO_CLOCKS_ON, &video->flags); }
static void aspeed_video_on(struct aspeed_video *video) { + if (test_bit(VIDEO_CLOCKS_ON, &video->flags)) + return; + /* Turn on the relevant clocks */ clk_prepare_enable(video->eclk); clk_prepare_enable(video->vclk); + + set_bit(VIDEO_CLOCKS_ON, &video->flags); }
static void aspeed_video_bufs_done(struct aspeed_video *video,