Re: [PATCH v5 20/22] xen/arm: ITS: Map ITS translation space

[Julien Grall <julien.grall@citrix.com>]

Hi Vijay,

On 27/07/2015 04:12, vijay.kilari@gmail.com wrote:
> From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
>
> ITS translation space contains GITS_TRANSLATOR register
> which is written by device to raise LPI. This space needs
> to mapped to every domain address space for all physical
> ITS available,so that device can access GITS_TRANSLATOR
> register using SMMU.
>
> Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>   xen/arch/arm/vgic-v3-its.c |   38 +++++++++++++++++++++++++++++++++++++-
>   1 file changed, 37 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/arm/vgic-v3-its.c b/xen/arch/arm/vgic-v3-its.c
> index e182cee..27523f4 100644
> --- a/xen/arch/arm/vgic-v3-its.c
> +++ b/xen/arch/arm/vgic-v3-its.c
> @@ -1060,6 +1060,42 @@ static const struct mmio_handler_ops vgic_gits_mmio_handler = {
>       .write_handler = vgic_v3_gits_mmio_write,
>   };
>
> +/*
> + * Map the 64K ITS translation space in guest.
> + * This is required purely for device smmu writes.
> +*/
> +
> +static int vits_map_translation_space(struct domain *d)
> +{
> +    uint64_t addr, size;
> +    int ret;
> +
> +    if ( !is_hardware_domain(d) )

Well this code is surely wrong. If you happen to have a guest domain, 
you won't map anything and say you've done it.

Given that vits_domain_init is only called for DOM0, you should drop 
this check.

> +        return 0;
> +
> +    ASSERT(is_domain_direct_mapped(d));
> +
> +    addr = d->arch.vgic.vits->gits_base + SZ_64K;
> +    size = SZ_64K;
> +
> +    /* Using 1:1 mapping to map translation space */
> +    /* TODO: Handle DomU mapping */
> +    ret = map_mmio_regions(d,
> +                           paddr_to_pfn(addr & PAGE_MASK),
> +                           DIV_ROUND_UP(size, PAGE_SIZE),
> +                           paddr_to_pfn(addr & PAGE_MASK));
> +
> +    if ( ret )
> +    {
> +         dprintk(XENLOG_G_ERR, "vITS: Unable to map to dom%d access to"
> +                 " 0x%"PRIx64" - 0x%"PRIx64"\n",

"Unable to map 0x...-0x... to dom%d"

> +                 d->domain_id,
> +                 addr & PAGE_MASK, PAGE_ALIGN(addr + size) - 1);
> +    }
> +
> +    return ret;
> +}
> +
>   int vits_domain_init(struct domain *d)
>   {
>       struct vgic_its *vits;
> @@ -1120,7 +1156,7 @@ int vits_domain_init(struct domain *d)
>
>       register_mmio_handler(d, &vgic_gits_mmio_handler, vits->gits_base, SZ_64K);
>
> -    return 0;
> +    return vits_map_translation_space(d);
>   }
>
>   void vits_domain_free(struct domain *d)
>

Regards,

-- 
Julien Grall