Re: [PATCH] clk: bcm: rpi: Mark ISP clock as critical

From: Stefan Wahren

Date: Tue Oct 28 2025 - 12:13:59 EST


Am 28.10.25 um 12:46 schrieb Jai Luthra:
The ISP clock should also be marked critical to prevent the clock
framework from disabling it on boot, which can lead to bus lockups when
the kernel tries to submit buffers to the VC4 ISP firmware.

Link: https://github.com/raspberrypi/linux/issues/7100
Fixes: 919d6924ae9b ("clk: bcm: rpi: Turn firmware clock on/off when preparing/unpreparing")
Signed-off-by: Jai Luthra <jai.luthra@xxxxxxxxxxxxxxxx>
Reviewed-by: Stefan Wahren <wahrenst@xxxxxxx>

Thanks
---
drivers/clk/bcm/clk-raspberrypi.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index 1a9162f0ae31e330c46f6eafdd00350599b0eede..dcc3ae5fb91650b042d52f02499922786b43afde 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -151,6 +151,7 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
[RPI_FIRMWARE_ISP_CLK_ID] = {
.export = true,
.minimize = true,
+ .flags = CLK_IS_CRITICAL,
},
[RPI_FIRMWARE_PIXEL_BVB_CLK_ID] = {
.export = true,

---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20251028-rpi-isp-clk-eb5c48346e51

Best regards,