Re: [Qemu-arm] [PATCH v1 1/1] arm_gic: Update ID registers based on revision

[Peter Maydell]

On 19 January 2016 at 01:33, Alistair Francis
<address@hidden> wrote:
> Update the GIC ID registers (registers above 0xfe0) based on the GIC
> revision instead of using the sames values for all GIC implementations.
>
> Signed-off-by: Alistair Francis <address@hidden>
> Tested-by: Sören Brinkmann <address@hidden>
> ---
>
>  hw/intc/arm_gic.c | 29 ++++++++++++++++++++++++++---
>  1 file changed, 26 insertions(+), 3 deletions(-)
>
> diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
> index 13e297d..f6bfa53 100644
> --- a/hw/intc/arm_gic.c
> +++ b/hw/intc/arm_gic.c
> @@ -31,8 +31,16 @@ do { fprintf(stderr, "arm_gic: " fmt , ## __VA_ARGS__); } 
> while (0)
>  #define DPRINTF(fmt, ...) do {} while(0)
>  #endif
>
> -static const uint8_t gic_id[] = {
> -    0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1
> +static const uint8_t gic_id_11mpcore[] = {
> +    0x00, 0x00, 0x00, 0x00, 0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1
> +};
> +
> +static const uint8_t gic_id_gicv1[] = {
> +    0x04, 0x00, 0x00, 0x00, 0x90, 0xb3, 0x1b, 0x00, 0x0d, 0xf0, 0x05, 0xb1
> +};
> +
> +static const uint8_t gic_id_gicv2[] = {
> +    0x04, 0x00, 0x00, 0x00, 0x90, 0xb4, 0x2b, 0x00, 0x0d, 0xf0, 0x05, 0xb1
>  };
>
>  static inline int gic_get_current_cpu(GICState *s)
> @@ -689,7 +697,22 @@ static uint32_t gic_dist_readb(void *opaque, hwaddr 
> offset, MemTxAttrs attrs)
>          if (offset & 3) {
>              res = 0;
>          } else {
> -            res = gic_id[(offset - 0xfe0) >> 2];
> +            switch (s->revision) {
> +            case REV_11MPCORE:
> +                res = gic_id_11mpcore[(offset - 0xfe0) >> 2];
> +                break;
> +            case 1:
> +                res = gic_id_gicv1[(offset - 0xfe0) >> 2];
> +                break;
> +            case 2:
> +                res = gic_id_gicv2[(offset - 0xfe0) >> 2];
> +                break;
> +            case REV_NVIC:
> +                /* Shouldn't be able to get here */
> +                abort();
> +            default:
> +                res = 0;
> +            }
>          }
>      }
>      return res;

You've expanded the arrays to include the fd0...fdc values
(which is right) but the logic also needs to change to
make offset == 0xfd0..0xfdf go through this code path and
also to use the new indexing into the array.

thanks
-- PMM