Re: [Xen-devel] [PATCH v2 2/2] xen/arm: platform: Add Raspberry Pi platform

[Stewart Hildebrand <Stewart.Hildebrand@xxxxxxxxxxxxxxx>]

On Wednesday, July 31, 2019 8:04 AM, Julien Grall <julien.grall@xxxxxxx> wrote:
>Hi Stewart,

Hi Julien

>On 29/07/2019 14:19, Stewart Hildebrand wrote:
>> The aux peripherals (uart1, spi1, and spi2) share an IRQ and a page of
>> memory. For debugging, it is helpful to use the aux UART in Xen. In
>> this case, Xen would try to assign spi1 and spi2 to dom0, but this
>> results in an error since the shared IRQ was already assigned to Xen.
>> Blacklist aux devices other than the UART to prevent mapping the shared
>> IRQ and memory range to dom0.
>
>Reading the commit message, it is unclear what's the impact on blacklist spi1
>and spi2. Could you expand it?

Yes, good thinking. What do you think about the following (the first paragraph 
is unchanged, just copied for completeness):

"The aux peripherals (uart1, spi1, and spi2) share an IRQ and a page of
memory. For debugging, it is helpful to use the aux UART in Xen. In
this case, Xen would try to assign spi1 and spi2 to dom0, but this
results in an error since the shared IRQ was already assigned to Xen.
Blacklist aux devices other than the UART to prevent mapping the shared
IRQ and memory range to dom0.

Blacklisting spi1 and spi2 unfortunately makes those peripherals
unavailable for use in the system. Future work could include forwarding
the IRQ for spi1 and spi2, and trap and mediate access to the memory
range for spi1 and spi2."

Would you like me to re-send the patch, or can the message be updated on commit?

Stew

>The rest of the patch looks good.
>
>Cheers,
>
>--
>Julien Grall
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel