Re: [PATCH] clocksource: sh_cmt: use CMTOUT_IE only when supported

From: Niklas Söderlund
Date: Mon Mar 08 2021 - 07:05:36 EST


Hi Wolfram,

Thanks for your patch.

On 2021-03-05 14:28:59 +0100, Wolfram Sang wrote:
> CMTOUT_IE is only supported for older SoCs. Newer SoCs shall not set
> this bit. So, add a version check.
>
> Reported-by: Phong Hoang <phong.hoang.wz@xxxxxxxxxxx>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>

> ---
>
> Confirmed with datasheets and could successfully repeat Niklas' CMT
> tests on an R-Car M3N based Salvator-XS.
>
> drivers/clocksource/sh_cmt.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
> index c98f8851fd68..3b53c6cb1da9 100644
> --- a/drivers/clocksource/sh_cmt.c
> +++ b/drivers/clocksource/sh_cmt.c
> @@ -143,6 +143,7 @@ struct sh_cmt_device {
> #define SH_CMT32_CMCSR_SSIE (1 << 10)
> #define SH_CMT32_CMCSR_CMS (1 << 9)
> #define SH_CMT32_CMCSR_CMM (1 << 8)
> +/* CMTOUT_IE only for SH_CMT_32BIT and SH_CMT_48BIT */
> #define SH_CMT32_CMCSR_CMTOUT_IE (1 << 7)
> #define SH_CMT32_CMCSR_CMR_NONE (0 << 4)
> #define SH_CMT32_CMCSR_CMR_DMA (1 << 4)
> @@ -339,8 +340,9 @@ static int sh_cmt_enable(struct sh_cmt_channel *ch)
> sh_cmt_write_cmcsr(ch, SH_CMT16_CMCSR_CMIE |
> SH_CMT16_CMCSR_CKS512);
> } else {
> - sh_cmt_write_cmcsr(ch, SH_CMT32_CMCSR_CMM |
> - SH_CMT32_CMCSR_CMTOUT_IE |
> + u32 cmtout = ch->cmt->info->model <= SH_CMT_48BIT ?
> + SH_CMT32_CMCSR_CMTOUT_IE : 0;
> + sh_cmt_write_cmcsr(ch, cmtout | SH_CMT32_CMCSR_CMM |
> SH_CMT32_CMCSR_CMR_IRQ |
> SH_CMT32_CMCSR_CKS_RCLK8);
> }
> --
> 2.29.2
>

--
Regards,
Niklas Söderlund