Re: [Qemu-devel] [PATCH RFC v8 12/12] hw/registerfields.h: Add 8bit and 16bit register macros.

[Alex Bennée]

Yoshinori Sato <address@hidden> writes:

> Some RX peripheral using 8bit and 16bit registers.
> Added 8bit and 16bit APIs.

Doesn't this mean the build breaks at some point? Features used by other
patches should be introduced first so the build remains bisectable.

>
> Signed-off-by: Yoshinori Sato <address@hidden>
> ---
>  include/hw/registerfields.h | 28 +++++++++++++++++++++++++++-
>  1 file changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/include/hw/registerfields.h b/include/hw/registerfields.h
> index 2659a58737..51bfd0cf67 100644
> --- a/include/hw/registerfields.h
> +++ b/include/hw/registerfields.h
> @@ -22,6 +22,14 @@
>      enum { A_ ## reg = (addr) };                                          \
>      enum { R_ ## reg = (addr) / 4 };
>
> +#define REG8(reg, addr)                                                  \
> +    enum { A_ ## reg = (addr) };                                          \
> +    enum { R_ ## reg = (addr) };
> +
> +#define REG16(reg, addr)                                                  \
> +    enum { A_ ## reg = (addr) };                                          \
> +    enum { R_ ## reg = (addr) / 2 };
> +
>  /* Define SHIFT, LENGTH and MASK constants for a field within a register */
>
>  /* This macro will define R_FOO_BAR_MASK, R_FOO_BAR_SHIFT and 
> R_FOO_BAR_LENGTH
> @@ -40,6 +48,8 @@
>  #define FIELD_EX64(storage, reg, field)                                   \
>      extract64((storage), R_ ## reg ## _ ## field ## _SHIFT,               \
>                R_ ## reg ## _ ## field ## _LENGTH)
> +#define FIELD_EX8  FIELD_EX32
> +#define FIELD_EX16 FIELD_EX32

Hmm maybe we should be defining extract16/extract8 in bitops so things
are a) properly types and b) bounds checked to catch errors.

>
>  /* Extract a field from an array of registers */
>  #define ARRAY_FIELD_EX32(regs, reg, field)                                \
> @@ -49,6 +59,22 @@
>   * Assigning values larger then the target field will result in
>   * compilation warnings.
>   */
> +#define FIELD_DP8(storage, reg, field, val) ({                            \
> +    struct {                                                              \
> +        unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
> +    } v = { .v = val };                                                   \
> +    uint8_t d;                                                            \
> +    d = deposit32((storage), R_ ## reg ## _ ## field ## _SHIFT,           \
> +                  R_ ## reg ## _ ## field ## _LENGTH, v.v);               \
> +    d; })
> +#define FIELD_DP16(storage, reg, field, val) ({                           \
> +    struct {                                                              \
> +        unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
> +    } v = { .v = val };                                                   \
> +    uint16_t d;                                                           \
> +    d = deposit32((storage), R_ ## reg ## _ ## field ## _SHIFT,           \
> +                  R_ ## reg ## _ ## field ## _LENGTH, v.v);               \
> +    d; })
>  #define FIELD_DP32(storage, reg, field, val) ({                           \
>      struct {                                                              \
>          unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
> @@ -57,7 +83,7 @@
>      d = deposit32((storage), R_ ## reg ## _ ## field ## _SHIFT,           \
>                    R_ ## reg ## _ ## field ## _LENGTH, v.v);               \
>      d; })
> -#define FIELD_DP64(storage, reg, field, val) ({                           \
> +#define FIELD_DP64(storage, reg, field, val) ({                         \
>      struct {                                                              \
>          unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
>      } v = { .v = val };                                                   \


--
Alex Bennée