| Message ID | 20231023233545.529519-2-mcanal@igalia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] pmdomain: bcm: bcm2835-power: check if the ASB register is equal to enable | expand |
On 10/23/2023 4:35 PM, Maíra Canal wrote: > The commit c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") > refactored the ASB control by using a general function to handle both > the enable and disable. But this patch introduced a subtle regression: > we need to check if !!(readl(base + reg) & ASB_ACK) == enable, not just > check if (readl(base + reg) & ASB_ACK) == true. > > Currently, this is causing an invalid register state in V3D when > unloading and loading the driver, because `bcm2835_asb_disable()` will > return -ETIMEDOUT and `bcm2835_asb_power_off()` will fail to disable the > ASB slave for V3D. > > Fixes: c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") > Signed-off-by: Maíra Canal <mcanal@igalia.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Good catch!
Hi Maíra, Am 24.10.23 um 01:35 schrieb Maíra Canal: > The commit c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") > refactored the ASB control by using a general function to handle both > the enable and disable. But this patch introduced a subtle regression: > we need to check if !!(readl(base + reg) & ASB_ACK) == enable, not just > check if (readl(base + reg) & ASB_ACK) == true. > > Currently, this is causing an invalid register state in V3D when > unloading and loading the driver, because `bcm2835_asb_disable()` will > return -ETIMEDOUT and `bcm2835_asb_power_off()` will fail to disable the > ASB slave for V3D. > > Fixes: c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") > Signed-off-by: Maíra Canal <mcanal@igalia.com> > --- could you please resubmit with a proper changelog (including the Reviewed-bys) of this patch? Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com> Thanks > drivers/pmdomain/bcm/bcm2835-power.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pmdomain/bcm/bcm2835-power.c b/drivers/pmdomain/bcm/bcm2835-power.c > index 1a179d4e011c..d2f0233cb620 100644 > --- a/drivers/pmdomain/bcm/bcm2835-power.c > +++ b/drivers/pmdomain/bcm/bcm2835-power.c > @@ -175,7 +175,7 @@ static int bcm2835_asb_control(struct bcm2835_power *power, u32 reg, bool enable > } > writel(PM_PASSWORD | val, base + reg); > > - while (readl(base + reg) & ASB_ACK) { > + while (!!(readl(base + reg) & ASB_ACK) == enable) { > cpu_relax(); > if (ktime_get_ns() - start >= 1000) > return -ETIMEDOUT; > -- > 2.41.0 >
diff --git a/drivers/pmdomain/bcm/bcm2835-power.c b/drivers/pmdomain/bcm/bcm2835-power.c index 1a179d4e011c..d2f0233cb620 100644 --- a/drivers/pmdomain/bcm/bcm2835-power.c +++ b/drivers/pmdomain/bcm/bcm2835-power.c @@ -175,7 +175,7 @@ static int bcm2835_asb_control(struct bcm2835_power *power, u32 reg, bool enable } writel(PM_PASSWORD | val, base + reg); - while (readl(base + reg) & ASB_ACK) { + while (!!(readl(base + reg) & ASB_ACK) == enable) { cpu_relax(); if (ktime_get_ns() - start >= 1000) return -ETIMEDOUT;
The commit c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") refactored the ASB control by using a general function to handle both the enable and disable. But this patch introduced a subtle regression: we need to check if !!(readl(base + reg) & ASB_ACK) == enable, not just check if (readl(base + reg) & ASB_ACK) == true. Currently, this is causing an invalid register state in V3D when unloading and loading the driver, because `bcm2835_asb_disable()` will return -ETIMEDOUT and `bcm2835_asb_power_off()` will fail to disable the ASB slave for V3D. Fixes: c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control") Signed-off-by: Maíra Canal <mcanal@igalia.com> --- drivers/pmdomain/bcm/bcm2835-power.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.41.0