Re: [PATCH v3 12/15] coresight: etm4x: Cleanup TRCSSCCRn and TRCSSCSRn register accesses

From: Mike Leach
Date: Tue Apr 12 2022 - 07:48:52 EST


On Fri, 4 Mar 2022 at 17:19, James Clark <james.clark@xxxxxxx> 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@xxxxxxx>
> ---
> drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +-
> drivers/hwtracing/coresight/coresight-etm4x-sysfs.c | 6 +++---
> drivers/hwtracing/coresight/coresight-etm4x.h | 4 ++++
> 3 files changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 88353f8ba414..87299e99dabb 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -443,7 +443,7 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
> for (i = 0; i < drvdata->nr_ss_cmp; i++) {
> /* always clear status bit on restart if using single-shot */
> if (config->ss_ctrl[i] || config->ss_pe_cmp[i])
> - config->ss_status[i] &= ~BIT(31);
> + config->ss_status[i] &= ~TRCSSCSRn_STATUS;
> etm4x_relaxed_write32(csa, config->ss_ctrl[i], TRCSSCCRn(i));
> etm4x_relaxed_write32(csa, config->ss_status[i], TRCSSCSRn(i));
> if (etm4x_sspcicrn_present(drvdata, i))
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> index 29188b1a4646..7dd7636fc2a7 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> @@ -1792,9 +1792,9 @@ static ssize_t sshot_ctrl_store(struct device *dev,
>
> spin_lock(&drvdata->spinlock);
> idx = config->ss_idx;
> - config->ss_ctrl[idx] = val & GENMASK(24, 0);
> + config->ss_ctrl[idx] = FIELD_PREP(TRCSSCCRn_SAC_ARC_RST_MASK, val);
> /* must clear bit 31 in related status register on programming */
> - config->ss_status[idx] &= ~BIT(31);
> + config->ss_status[idx] &= ~TRCSSCSRn_STATUS;
> spin_unlock(&drvdata->spinlock);
> return size;
> }
> @@ -1844,7 +1844,7 @@ static ssize_t sshot_pe_ctrl_store(struct device *dev,
> idx = config->ss_idx;
> config->ss_pe_cmp[idx] = val & GENMASK(7, 0);
> /* must clear bit 31 in related status register on programming */
> - config->ss_status[idx] &= ~BIT(31);
> + config->ss_status[idx] &= ~TRCSSCSRn_STATUS;
> spin_unlock(&drvdata->spinlock);
> return size;
> }
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
> index 802ddbe2eecd..b4217eaab450 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.h
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h
> @@ -214,6 +214,10 @@
> #define TRCACATRn_CONTEXTTYPE_VMID BIT(3)
> #define TRCACATRn_CONTEXT_MASK GENMASK(6, 4)
> #define TRCACATRn_EXLEVEL_MASK GENMASK(14, 8)
> +
> +#define TRCSSCSRn_STATUS BIT(31)
> +#define TRCSSCCRn_SAC_ARC_RST_MASK GENMASK(24, 0)
> +
> /*
> * System instructions to access ETM registers.
> * See ETMv4.4 spec ARM IHI0064F section 4.3.6 System instructions
> --
> 2.28.0
>

Reviewed-by: Mike Leach <mike.leach@xxxxxxxxxx>

--
Mike Leach
Principal Engineer, ARM Ltd.
Manchester Design Centre. UK