Re: [PATCH] irqchip/gic-v3-its: Fix probing for ITT_entry_size

From: Marc Zyngier
Date: Thu Jan 31 2019 - 07:48:37 EST


On 31/01/2019 11:19, Zenghui Yu wrote:
> According to ARM IHI 0069C (ID070116), we should use GITS_TYPER's
> bits [7:4] as ITT_entry_size.
>
> Signed-off-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>
> ---
> include/linux/irqchip/arm-gic-v3.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
> index 071b4cb..c848a7c 100644
> --- a/include/linux/irqchip/arm-gic-v3.h
> +++ b/include/linux/irqchip/arm-gic-v3.h
> @@ -319,7 +319,7 @@
> #define GITS_TYPER_PLPIS (1UL << 0)
> #define GITS_TYPER_VLPIS (1UL << 1)
> #define GITS_TYPER_ITT_ENTRY_SIZE_SHIFT 4
> -#define GITS_TYPER_ITT_ENTRY_SIZE(r) ((((r) >> GITS_TYPER_ITT_ENTRY_SIZE_SHIFT) & 0x1f) + 1)
> +#define GITS_TYPER_ITT_ENTRY_SIZE(r) ((((r) >> GITS_TYPER_ITT_ENTRY_SIZE_SHIFT) & 0xf) + 1)
> #define GITS_TYPER_IDBITS_SHIFT 8
> #define GITS_TYPER_DEVBITS_SHIFT 13
> #define GITS_TYPER_DEVBITS(r) ((((r) >> GITS_TYPER_DEVBITS_SHIFT) & 0x1f) + 1)
>

Well spotted. I've applied this as a fix after having added the relevant
Fixes: tag and massaged the commit message a bit.

Thanks,

M.
--
Jazz is not dead. It just smells funny...