Hi Maíra,
Am 12.03.26 um 22:34 schrieb Maíra Canal:
The bcm2835_asb_control() function uses a tight polling loop to wait
for the ASB bridge to acknowledge a request. During intensive workloads,
this handshake intermittently fails for V3D's master ASB on BCM2711,
resulting in "Failed to disable ASB master for v3d" errors during
runtime PM suspend. As a consequence, the failed power-off leaves V3D in
a broken state, leading to bus faults or system hangs on later accesses.
As the timeout is insufficient in some scenarios, increase the polling
timeout from 1us to 5us, which is still negligible in the context of a
power domain transition. Also, move the start timestamp to after the
MMIO write, as the write latency is counted against the timeout,
reducing the effective wait time for the hardware to respond.
Cc: [email protected]
I think, a Fixes tag would be helpful here. Also this fix should be the
first patch of the series or separate.
Reviewed-by: Stefan Wahren <[email protected]>
Signed-off-by: Maíra Canal <[email protected]>
---
To: Ulf Hansson <[email protected]>
To: Ray Jui <[email protected]>
To: Scott Branden <[email protected]>
Cc: [email protected]
This looks unusual. Is this intended?
Best regards
---
drivers/pmdomain/bcm/bcm2835-power.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/pmdomain/bcm/bcm2835-power.c
b/drivers/pmdomain/bcm/bcm2835-power.c
index
0450202bbee2513c9116a36abaa839b460550935..1815eb4ee69b9b672b5e314402f1cc9897c57dcb
100644
--- a/drivers/pmdomain/bcm/bcm2835-power.c
+++ b/drivers/pmdomain/bcm/bcm2835-power.c
@@ -166,8 +166,6 @@ static int bcm2835_asb_control(struct bcm2835_power *power,
u32 reg, bool enable
break;
}
- start = ktime_get_ns();
-
/* Enable the module's async AXI bridges. */
if (enable) {
val = readl(base + reg) & ~ASB_REQ_STOP;
@@ -176,9 +174,10 @@ static int bcm2835_asb_control(struct bcm2835_power
*power, u32 reg, bool enable
}
writel(PM_PASSWORD | val, base + reg);
+ start = ktime_get_ns();
while (!!(readl(base + reg) & ASB_ACK) == enable) {
cpu_relax();
- if (ktime_get_ns() - start >= 1000)
+ if (ktime_get_ns() - start >= 5000)
return -ETIMEDOUT;
}
