Re: [PATCH v3 07/15] coresight: etm4x: Cleanup TRCEVENTCTL1R register accesses

[Mike Leach]

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>
> ---
>  .../coresight/coresight-etm4x-sysfs.c         | 25 +++++++++++--------
>  drivers/hwtracing/coresight/coresight-etm4x.h |  8 ++++++
>  2 files changed, 23 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> index 53f84da3fe44..2d29e9daf515 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> @@ -384,16 +384,16 @@ static ssize_t mode_store(struct device *dev,
>         /* bit[11], AMBA Trace Bus (ATB) trigger enable bit */
>         if ((config->mode & ETM_MODE_ATB_TRIGGER) &&
>             (drvdata->atbtrig == true))
> -               config->eventctrl1 |= BIT(11);
> +               config->eventctrl1 |= TRCEVENTCTL1R_ATB;
>         else
> -               config->eventctrl1 &= ~BIT(11);
> +               config->eventctrl1 &= ~TRCEVENTCTL1R_ATB;
>
>         /* bit[12], Low-power state behavior override bit */
>         if ((config->mode & ETM_MODE_LPOVERRIDE) &&
>             (drvdata->lpoverride == true))
> -               config->eventctrl1 |= BIT(12);
> +               config->eventctrl1 |= TRCEVENTCTL1R_LPOVERRIDE;
>         else
> -               config->eventctrl1 &= ~BIT(12);
> +               config->eventctrl1 &= ~TRCEVENTCTL1R_LPOVERRIDE;
>
>         /* bit[8], Instruction stall bit */
>         if ((config->mode & ETM_MODE_ISTALL_EN) && (drvdata->stallctl == true))
> @@ -534,7 +534,7 @@ static ssize_t event_instren_show(struct device *dev,
>         struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
>         struct etmv4_config *config = &drvdata->config;
>
> -       val = BMVAL(config->eventctrl1, 0, 3);
> +       val = FIELD_GET(TRCEVENTCTL1R_INSTEN_MASK, config->eventctrl1);
>         return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
>  }
>
> @@ -551,23 +551,28 @@ static ssize_t event_instren_store(struct device *dev,
>
>         spin_lock(&drvdata->spinlock);
>         /* start by clearing all instruction event enable bits */
> -       config->eventctrl1 &= ~(BIT(0) | BIT(1) | BIT(2) | BIT(3));
> +       config->eventctrl1 &= ~TRCEVENTCTL1R_INSTEN_MASK;
>         switch (drvdata->nr_event) {
>         case 0x0:
>                 /* generate Event element for event 1 */
> -               config->eventctrl1 |= val & BIT(1);
> +               config->eventctrl1 |= val & TRCEVENTCTL1R_INSTEN_1;
>                 break;
>         case 0x1:
>                 /* generate Event element for event 1 and 2 */
> -               config->eventctrl1 |= val & (BIT(0) | BIT(1));
> +               config->eventctrl1 |= val & (TRCEVENTCTL1R_INSTEN_0 | TRCEVENTCTL1R_INSTEN_1);
>                 break;
>         case 0x2:
>                 /* generate Event element for event 1, 2 and 3 */
> -               config->eventctrl1 |= val & (BIT(0) | BIT(1) | BIT(2));
> +               config->eventctrl1 |= val & (TRCEVENTCTL1R_INSTEN_0 |
> +                                            TRCEVENTCTL1R_INSTEN_1 |
> +                                            TRCEVENTCTL1R_INSTEN_2);
>                 break;
>         case 0x3:
>                 /* generate Event element for all 4 events */
> -               config->eventctrl1 |= val & 0xF;
> +               config->eventctrl1 |= val & (TRCEVENTCTL1R_INSTEN_0 |
> +                                            TRCEVENTCTL1R_INSTEN_1 |
> +                                            TRCEVENTCTL1R_INSTEN_2 |
> +                                            TRCEVENTCTL1R_INSTEN_3);
>                 break;
>         default:
>                 break;
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
> index 4c8d7be3c159..cbba46f14ada 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.h
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h
> @@ -188,6 +188,14 @@
>  #define TRCCONFIGR_DA                          BIT(16)
>  #define TRCCONFIGR_DV                          BIT(17)
>
> +#define TRCEVENTCTL1R_INSTEN_MASK              GENMASK(3, 0)
> +#define TRCEVENTCTL1R_INSTEN_0                 BIT(0)
> +#define TRCEVENTCTL1R_INSTEN_1                 BIT(1)
> +#define TRCEVENTCTL1R_INSTEN_2                 BIT(2)
> +#define TRCEVENTCTL1R_INSTEN_3                 BIT(3)
> +#define TRCEVENTCTL1R_ATB                      BIT(11)
> +#define TRCEVENTCTL1R_LPOVERRIDE               BIT(12)
> +
>  /*
>   * 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