[PATCH v3] pmdomain: bcm: bcm2835-power: check if the ASB register is equal to enable
Ulf Hansson
ulf.hansson at linaro.org
Tue Oct 24 03:43:58 PDT 2023
On Tue, 24 Oct 2023 at 12:13, Maíra Canal <mcanal at igalia.com> 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.
>
> [v2]:
> * Use the !! operator to assure the correct assertion (Stefan Wahren)
>
> [v3]:
> * Include a changelog (Stefan Wahren)
> * Include Florian's and Stefan's Reviewed-by
The version information belongs a few lines below.
>
> Fixes: c494a447c14e ("soc: bcm: bcm2835-power: Refactor ASB control")
> Signed-off-by: Maíra Canal <mcanal at igalia.com>
> Reviewed-by: Florian Fainelli <florian.fainelli at broadcom.com>
> Reviewed-by: Stefan Wahren <stefan.wahren at i2se.com>
No need to resend this time. I have amended the patch to remove the
version information from the commit message, applied it for fixes and
added a stable tag!
Kind regards
Uffe
> ---
This is where you manually need to edit the format patch-file to add
the version information.
End the section with three dashes and a newline, like below:
---
> 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
>
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