[PATCH 2/5] coresight: etmv4: Fix ETMv4x peripheral ID table

Mathieu Poirier mathieu.poirier at linaro.org
Tue May 31 10:45:38 PDT 2016


On 31 May 2016 at 05:57, Suzuki K Poulose <suzuki.poulose at arm.com> wrote:
> This patch cleans up the peripheral id table for different ETMv4
> implementations.
>
> As per Cortex-A53 TRM, the ETM has following id values:
>
> Peripheral ID0  0x5D    0xFE0
> Peripheral ID1  0xB9    0xFE4
> Peripheral ID2  0x4B    0xFE8
> Peripheral ID3  0x00    0xFEC
>
> where, PID2: has the following format:
>
> [7:4]   Revision
> [3]     JEDEC   0b1     res1. Indicates a JEP106 identity code is used
> [2:0]   DES_1   0b011   ARM Limited. This is bits[6:4] of JEP106 ID code
>
> The existing table entry checks only the bits [1:0], which is not
> sufficient enough. Fix it to match bits [3:0], just like the other
> entries do. While at it, correct the comment for A57 and the A53 entry.
>
> Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> ---
>  drivers/hwtracing/coresight/coresight-etm4x.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
> index 462f0dc..88947f3 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.c
> @@ -815,12 +815,12 @@ err_arch_supported:
>  }
>
>  static struct amba_id etm4_ids[] = {
> -       {       /* ETM 4.0 - Qualcomm */
> -               .id     = 0x0003b95d,
> -               .mask   = 0x0003ffff,
> +       {       /* ETM 4.0 - Cortex-A53  */
> +               .id     = 0x000bb95d,
> +               .mask   = 0x000fffff,
>                 .data   = "ETM 4.0",
>         },
> -       {       /* ETM 4.0 - Juno board */
> +       {       /* ETM 4.0 - Cortex-A57 */
>                 .id     = 0x000bb95e,
>                 .mask   = 0x000fffff,
>                 .data   = "ETM 4.0",
> --
> 1.9.1
>

I'll apply this to my next tree but since it doesn't cause a core dump
or prevent the kernel from booting, I don't think it deserves to be in
-rc2.

Thanks,
Mathieu



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