Re: [Qemu-devel] [PATCH v4 11/17] hw/intc/arm_gic: Handle grouping for GICC_HPPIR

[Edgar E. Iglesias]

On Fri, May 01, 2015 at 06:50:37PM +0100, Peter Maydell wrote:
> From: Fabian Aggeler <address@hidden>
> 
> Grouping (GICv2) and Security Extensions change the behaviour of reads
> of the highest priority pending interrupt register (ICCHPIR/GICC_HPPIR).
> 
> Signed-off-by: Fabian Aggeler <address@hidden>
> Signed-off-by: Greg Bellows <address@hidden>
> Message-id: address@hidden
> [PMM: make utility fn static; coding style fixes; AckCtl has an effect
>  for GICv2 without security extensions as well; removed checks on enable
>  bits because these are done when we set current_pending[cpu]]
> Signed-off-by: Peter Maydell <address@hidden>


Reviewed-by: Edgar E. Iglesias <address@hidden>


> ---
>  hw/intc/arm_gic.c | 28 +++++++++++++++++++++++++++-
>  1 file changed, 27 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
> index 7c0ddc8..75c69b3 100644
> --- a/hw/intc/arm_gic.c
> +++ b/hw/intc/arm_gic.c
> @@ -176,6 +176,32 @@ static void gic_set_irq(void *opaque, int irq, int level)
>      gic_update(s);
>  }
>  
> +static uint16_t gic_get_current_pending_irq(GICState *s, int cpu,
> +                                            MemTxAttrs attrs)
> +{
> +    uint16_t pending_irq = s->current_pending[cpu];
> +
> +    if (pending_irq < GIC_MAXIRQ && gic_has_groups(s)) {
> +        int group = GIC_TEST_GROUP(pending_irq, (1 << cpu));
> +        /* On a GIC without the security extensions, reading this register
> +         * behaves in the same way as a secure access to a GIC with them.
> +         */
> +        bool secure = !s->security_extn || attrs.secure;
> +
> +        if (group == 0 && !secure) {
> +            /* Group0 interrupts hidden from Non-secure access */
> +            return 1023;
> +        }
> +        if (group == 1 && secure && !(s->cpu_ctlr[cpu] & GICC_CTLR_ACK_CTL)) 
> {
> +            /* Group1 interrupts only seen by Secure access if
> +             * AckCtl bit set.
> +             */
> +            return 1022;
> +        }
> +    }
> +    return pending_irq;
> +}
> +
>  static void gic_set_running_irq(GICState *s, int cpu, int irq)
>  {
>      s->running_irq[cpu] = irq;
> @@ -890,7 +916,7 @@ static MemTxResult gic_cpu_read(GICState *s, int cpu, int 
> offset,
>          *data = gic_get_running_priority(s, cpu, attrs);
>          break;
>      case 0x18: /* Highest Pending Interrupt */
> -        *data = s->current_pending[cpu];
> +        *data = gic_get_current_pending_irq(s, cpu, attrs);
>          break;
>      case 0x1c: /* Aliased Binary Point */
>          /* GIC v2, no security: ABPR
> -- 
> 1.9.1
>