Re: [RFC v2] hw/registerfields: add `FIELDx_1CLEAR()` macro

[Alistair Francis <alistair23@gmail.com>]

On Tue, Sep 27, 2022 at 10:58 AM Wilfred Mallawa
<wilfred.mallawa@opensource.wdc.com> wrote:
>
> From: Wilfred Mallawa <wilfred.mallawa@wdc.com>
>
> Changes from V1:
>         * Instead of needing all field bits to be set
>           we clear the field if any are set. If the field is
>           0/clear then no change.

The changelog should go

>
> Adds a helper macro that implements the register `w1c`
> functionality.
>
> Ex:
>   uint32_t data = FIELD32_1CLEAR(val, REG, FIELD);
>
> If ANY bits of the specified `FIELD` is set
> then the respective field is cleared and returned to `data`.
>
> If the field is cleared (0), then no change and
> val is returned.
>
> Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
> ---

Below this line.

Otherwise the patch looks good. Do you mind adding it to a series that
converts the OT SPI to use these macros?

>  include/hw/registerfields.h | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>
> diff --git a/include/hw/registerfields.h b/include/hw/registerfields.h
> index 1330ca77de..4a6a228339 100644
> --- a/include/hw/registerfields.h
> +++ b/include/hw/registerfields.h
> @@ -115,6 +115,28 @@
>                    R_ ## reg ## _ ## field ## _LENGTH, _v.v);              \
>      _d; })
>
> +/*
> + * Clear the specified field in reg_val if
> + * any field bits are set, else no changes made. Implements
> + * single/multi-bit `w1c`
> + *
> + */
> +#define FIELD8_1CLEAR(reg_val, reg, field)                                \

These should probably match the other macros with:

(storage, reg, field)

Alistair