Re: [PATCH v3 15/15] coresight: etm4x: Cleanup TRCRSCTLRn register accesses

Mathieu Poirier
2022-03-23T16:15:59Z

On Fri, Mar 04, 2022 at 05:19:12PM +0000, James Clark wrote:
> This is a no-op change for style and consistency and has no effect on
> the binary output by the compiler. In sysreg.h fields are defined as
> the register name followed by the field name and then _MASK. This
> allows for grepping for fields by name rather than using magic numbers.
>
> Signed-off-by: James Clark <james.clark@arm.com>
> ---
> drivers/hwtracing/coresight/coresight-etm4x-sysfs.c | 7 +++++--
> drivers/hwtracing/coresight/coresight-etm4x.h | 7 +++++++
> 2 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> index 3ae6f4432646..6ea8181816fc 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> @@ -1726,8 +1726,11 @@ static ssize_t res_ctrl_store(struct device *dev,
> /* For odd idx pair inversal bit is RES0 */
> if (idx % 2 != 0)
> /* PAIRINV, bit[21] */
> - val &= ~BIT(21);
> - config->res_ctrl[idx] = val & GENMASK(21, 0);
> + val &= ~TRCRSCTLRn_PAIRINV;
> + config->res_ctrl[idx] = val & (TRCRSCTLRn_PAIRINV |
> + TRCRSCTLRn_INV |
> + TRCRSCTLRn_GROUP_MASK |
> + TRCRSCTLRn_SELECT_MASK);
> spin_unlock(&drvdata->spinlock);
> return size;
> }
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
> index 15704982357f..2c412841b126 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.h
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h
> @@ -223,6 +223,13 @@
> #define TRCBBCTLR_MODE BIT(8)
> #define TRCBBCTLR_RANGE_MASK GENMASK(7, 0)
>
> +#define TRCRSCTLRn_PAIRINV BIT(21)
> +#define TRCRSCTLRn_INV BIT(20)
> +#define TRCRSCTLRn_GROUP_MASK GENMASK(19, 16)
> +#define TRCRSCTLRn_SELECT_MASK GENMASK(15, 0)
> +
> +
> +

Two extra lines.

> /*
> * System instructions to access ETM registers.
> * See ETMv4.4 spec ARM IHI0064F section 4.3.6 System instructions
> --
> 2.28.0
>