Re: [PATCH v3 06/24] xen/arm: Map disabled device in DOM0

[Ian Campbell <ian.campbell@citrix.com>]

On Tue, 2015-01-13 at 14:25 +0000, Julien Grall wrote:
> The check to avoid mapping disabled device in DOM0 was added in the anticipation

"disabled devices" and "in anticipation of device passthrough"

> of the device passthrough. But, a brand new property will be added later to mark
> device which will passthrough. At the same time, remove the memory type

"which will be passedthrough" or maybe "which will be passthrough"?
(It's hard to say because passthrough isn't really a word...)

> check because those nodes has been blacklisted.
> 
> Futhermore, some platform (such as the OMAP) may try to poke device even

"Furthermore".

> if the property "status" is set to "disabled".
> 
> Signed-off-by: Julien Grall <julien.grall@linaro.org>
> Cc: Andrii Tseglytskyi <andrii.tseglytskyi@globallogic.com>

With that and the change Stefano requested:
Acked-by: Ian Campbell <ian.campbell@citrix.com>

> 
> ---
> 
>     Changes in v3:
>         - Patch added
>         - "xen/arm: follow-up to allow DOM0 manage IRQ and MMIO" has
>         been split in 2 patch [1]
>         - Drop the check for memory type. Thoses nodes have been
>         blacklisted.
> 
> [1] https://patches.linaro.org/34669/
> ---
>  xen/arch/arm/domain_build.c    | 19 +++----------------
>  xen/arch/arm/platforms/omap5.c | 12 ------------
>  2 files changed, 3 insertions(+), 28 deletions(-)
> 
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index 8f1b48e..f68755f 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -1104,22 +1104,9 @@ static int handle_node(struct domain *d, struct kernel_info *kinfo,
>          return 0;
>      }
>  
> -    /*
> -     * Some device doesn't need to be mapped in Xen:
> -     *  - Memory: the guest will see a different view of memory. It will
> -     *  be allocated later.
> -     *  - Disabled device: Linux is able to cope with status="disabled"
> -     *  property. Therefore these device doesn't need to be mapped. This
> -     *  solution can be use later for pass through.
> -     */
> -    if ( !dt_device_type_is_equal(node, "memory") &&
> -         dt_device_is_available(node) )
> -    {
> -        res = map_device(d, node);
> -
> -        if ( res )
> -            return res;
> -    }
> +    res = map_device(d, node);
> +    if ( res)
> +        return res;
>  
>      /*
>       * The property "name" is used to have a different name on older FDT
> diff --git a/xen/arch/arm/platforms/omap5.c b/xen/arch/arm/platforms/omap5.c
> index 9d6e504..e7bf30d 100644
> --- a/xen/arch/arm/platforms/omap5.c
> +++ b/xen/arch/arm/platforms/omap5.c
> @@ -155,17 +155,6 @@ static const char * const dra7_dt_compat[] __initconst =
>      NULL
>  };
>  
> -static const struct dt_device_match dra7_blacklist_dev[] __initconst =
> -{
> -    /* OMAP Linux kernel handles devices with status "disabled" in a
> -     * weird manner - tries to reset them. While their memory ranges
> -     * are not mapped, this leads to data aborts, so skip these devices
> -     * from DT for dom0.
> -     */
> -    DT_MATCH_NOT_AVAILABLE(),
> -    { /* sentinel */ },
> -};
> -
>  PLATFORM_START(omap5, "TI OMAP5")
>      .compatible = omap5_dt_compat,
>      .init_time = omap5_init_time,
> @@ -185,7 +174,6 @@ PLATFORM_START(dra7, "TI DRA7")
>  
>      .dom0_gnttab_start = 0x4b000000,
>      .dom0_gnttab_size = 0x20000,
> -    .blacklist_dev = dra7_blacklist_dev,
>  PLATFORM_END
>  
>  /*