Re: [PATCH v3 04/15] coresight: etm4x: Cleanup TRCIDR4 register accesses

Mike Leach
2022-04-12T09:36:27Z

On Fri, 4 Mar 2022 at 17:19, James Clark <james.clark@arm.com> 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-core.c | 12 ++++++------
> drivers/hwtracing/coresight/coresight-etm4x.h | 8 ++++++++
> 2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 1b377f6b31bf..c52ab7f29f41 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -1155,9 +1155,9 @@ static void etm4_init_arch_data(void *info)
> /* number of resources trace unit supports */
> etmidr4 = etm4x_relaxed_read32(csa, TRCIDR4);
> /* NUMACPAIRS, bits[0:3] number of addr comparator pairs for tracing */
> - drvdata->nr_addr_cmp = BMVAL(etmidr4, 0, 3);
> + drvdata->nr_addr_cmp = FIELD_GET(TRCIDR4_NUMACPAIRS_MASK, etmidr4);
> /* NUMPC, bits[15:12] number of PE comparator inputs for tracing */
> - drvdata->nr_pe_cmp = BMVAL(etmidr4, 12, 15);
> + drvdata->nr_pe_cmp = FIELD_GET(TRCIDR4_NUMPC_MASK, etmidr4);
> /*
> * NUMRSPAIR, bits[19:16]
> * The number of resource pairs conveyed by the HW starts at 0, i.e a
> @@ -1168,7 +1168,7 @@ static void etm4_init_arch_data(void *info)
> * the default TRUE and FALSE resource selectors are omitted.
> * Otherwise for values 0x1 and above the number is N + 1 as per v4.2.
> */
> - drvdata->nr_resource = BMVAL(etmidr4, 16, 19);
> + drvdata->nr_resource = FIELD_GET(TRCIDR4_NUMRSPAIR_MASK, etmidr4);
> if ((drvdata->arch < ETM_ARCH_V4_3) || (drvdata->nr_resource > 0))
> drvdata->nr_resource += 1;
> /*
> @@ -1176,15 +1176,15 @@ static void etm4_init_arch_data(void *info)
> * comparator control for tracing. Read any status regs as these
> * also contain RO capability data.
> */
> - drvdata->nr_ss_cmp = BMVAL(etmidr4, 20, 23);
> + drvdata->nr_ss_cmp = FIELD_GET(TRCIDR4_NUMSSCC_MASK, etmidr4);
> for (i = 0; i < drvdata->nr_ss_cmp; i++) {
> drvdata->config.ss_status[i] =
> etm4x_relaxed_read32(csa, TRCSSCSRn(i));
> }
> /* NUMCIDC, bits[27:24] number of Context ID comparators for tracing */
> - drvdata->numcidc = BMVAL(etmidr4, 24, 27);
> + drvdata->numcidc = FIELD_GET(TRCIDR4_NUMCIDC_MASK, etmidr4);
> /* NUMVMIDC, bits[31:28] number of VMID comparators for tracing */
> - drvdata->numvmidc = BMVAL(etmidr4, 28, 31);
> + drvdata->numvmidc = FIELD_GET(TRCIDR4_NUMVMIDC_MASK, etmidr4);
>
> etmidr5 = etm4x_relaxed_read32(csa, TRCIDR5);
> /* NUMEXTIN, bits[8:0] number of external inputs implemented */
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
> index 1b95c63938f0..c9c5fd655196 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.h
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h
> @@ -157,6 +157,14 @@
> #define TRCIDR3_NUMPROC_LO_MASK GENMASK(30, 28)
> #define TRCIDR3_NUMPROC_HI_MASK GENMASK(13, 12)
> #define TRCIDR3_NOOVERFLOW BIT(31)
> +
> +#define TRCIDR4_NUMACPAIRS_MASK GENMASK(3, 0)
> +#define TRCIDR4_NUMPC_MASK GENMASK(15, 12)
> +#define TRCIDR4_NUMRSPAIR_MASK GENMASK(19, 16)
> +#define TRCIDR4_NUMSSCC_MASK GENMASK(23, 20)
> +#define TRCIDR4_NUMCIDC_MASK GENMASK(27, 24)
> +#define TRCIDR4_NUMVMIDC_MASK GENMASK(31, 28)
> +
> /*
> * 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@linaro.org>
--
Mike Leach
Principal Engineer, ARM Ltd.
Manchester Design Centre. UK