Linux Virtualization - Jul 2015 - [PATCH] virtio_mmio: add ACPI probing

On 28 July 2015 at 11:08, Michael S. Tsirkin <mst at redhat.com>
wrote:
> On Tue, Jul 28, 2015 at 10:44:02AM +0100, Graeme Gregory wrote:
>> Added the match table and pointers for ACPI probing to the driver.
>>
>> This uses the same identifier for virt devices as being used for qemu
>> ARM64 ACPI support.
>>
>>
http://git.linaro.org/people/shannon.zhao/qemu.git/commit/d0bf1955a3ecbab4b51d46f8c5dda02b7e14a17e
>>
>> Signed-off-by: Graeme Gregory <graeme.gregory at linaro.org>
>> ---
>>  drivers/virtio/virtio_mmio.c | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/drivers/virtio/virtio_mmio.c
b/drivers/virtio/virtio_mmio.c
>> index 10189b5..f499d9d 100644
>> --- a/drivers/virtio/virtio_mmio.c
>> +++ b/drivers/virtio/virtio_mmio.c
>> @@ -58,6 +58,7 @@
>>
>>  #define pr_fmt(fmt) "virtio-mmio: " fmt
>>
>> +#include <linux/acpi.h>
>>  #include <linux/highmem.h>
>>  #include <linux/interrupt.h>
>>  #include <linux/io.h>
>> @@ -732,12 +733,21 @@ static struct of_device_id virtio_mmio_match[] =
{
>>  };
>>  MODULE_DEVICE_TABLE(of, virtio_mmio_match);
>>
>> +#ifdef CONFIG_ACPI
>> +static const struct acpi_device_id virtio_mmio_acpi_match[] = {
>> +     { "LNRO0005", },
>> +     { }
>> +};
>
> Hmm - we have reserved QEMUXXXX in ASWG explicitly for this purpose.
>
> Pater - do you think it's a good idea to change this before QEMU 2.4
> is released?
Shannon's call, I guess. I don't know enough about ACPI to say.
I thought these ACPI IDs were already fixed because they were
what the kernel was looking for...

-- PMM

On Tue, Jul 28, 2015 at 11:12:33AM +0100, Peter Maydell
wrote:
> On 28 July 2015 at 11:08, Michael S. Tsirkin <mst at redhat.com>
wrote:
> > On Tue, Jul 28, 2015 at 10:44:02AM +0100, Graeme Gregory wrote:
> >> Added the match table and pointers for ACPI probing to the driver.
> >>
> >> This uses the same identifier for virt devices as being used for
qemu
> >> ARM64 ACPI support.
> >>
> >>
http://git.linaro.org/people/shannon.zhao/qemu.git/commit/d0bf1955a3ecbab4b51d46f8c5dda02b7e14a17e
> >>
> >> Signed-off-by: Graeme Gregory <graeme.gregory at linaro.org>
> >> ---
> >>  drivers/virtio/virtio_mmio.c | 10 ++++++++++
> >>  1 file changed, 10 insertions(+)
> >>
> >> diff --git a/drivers/virtio/virtio_mmio.c
b/drivers/virtio/virtio_mmio.c
> >> index 10189b5..f499d9d 100644
> >> --- a/drivers/virtio/virtio_mmio.c
> >> +++ b/drivers/virtio/virtio_mmio.c
> >> @@ -58,6 +58,7 @@
> >>
> >>  #define pr_fmt(fmt) "virtio-mmio: " fmt
> >>
> >> +#include <linux/acpi.h>
> >>  #include <linux/highmem.h>
> >>  #include <linux/interrupt.h>
> >>  #include <linux/io.h>
> >> @@ -732,12 +733,21 @@ static struct of_device_id
virtio_mmio_match[] = {
> >>  };
> >>  MODULE_DEVICE_TABLE(of, virtio_mmio_match);
> >>
> >> +#ifdef CONFIG_ACPI
> >> +static const struct acpi_device_id virtio_mmio_acpi_match[] = {
> >> +     { "LNRO0005", },
> >> +     { }
> >> +};
> >
> > Hmm - we have reserved QEMUXXXX in ASWG explicitly for this purpose.
> >
> > Pater - do you think it's a good idea to change this before QEMU
2.4
> > is released?
> 
> Shannon's call, I guess. I don't know enough about ACPI to say.
> I thought these ACPI IDs were already fixed because they were
> what the kernel was looking for...
> 
> -- PMM
Apparently not :)

-- 
MST

On 28 July 2015 at 11:27, Michael S. Tsirkin <mst at redhat.com>
wrote:
> On Tue, Jul 28, 2015 at 11:12:33AM +0100, Peter Maydell wrote:
>> On 28 July 2015 at 11:08, Michael S. Tsirkin <mst at redhat.com>
wrote:
>> > On Tue, Jul 28, 2015 at 10:44:02AM +0100, Graeme Gregory wrote:
>> >> Added the match table and pointers for ACPI probing to the
driver.
>> >>
>> >> This uses the same identifier for virt devices as being used
for qemu
>> >> ARM64 ACPI support.
>> >>
>> >>
http://git.linaro.org/people/shannon.zhao/qemu.git/commit/d0bf1955a3ecbab4b51d46f8c5dda02b7e14a17e
>> >>
>> >> Signed-off-by: Graeme Gregory <graeme.gregory at
linaro.org>
>> >> ---
>> >>  drivers/virtio/virtio_mmio.c | 10 ++++++++++
>> >>  1 file changed, 10 insertions(+)
>> >>
>> >> diff --git a/drivers/virtio/virtio_mmio.c
b/drivers/virtio/virtio_mmio.c
>> >> index 10189b5..f499d9d 100644
>> >> --- a/drivers/virtio/virtio_mmio.c
>> >> +++ b/drivers/virtio/virtio_mmio.c
>> >> @@ -58,6 +58,7 @@
>> >>
>> >>  #define pr_fmt(fmt) "virtio-mmio: " fmt
>> >>
>> >> +#include <linux/acpi.h>
>> >>  #include <linux/highmem.h>
>> >>  #include <linux/interrupt.h>
>> >>  #include <linux/io.h>
>> >> @@ -732,12 +733,21 @@ static struct of_device_id
virtio_mmio_match[] = {
>> >>  };
>> >>  MODULE_DEVICE_TABLE(of, virtio_mmio_match);
>> >>
>> >> +#ifdef CONFIG_ACPI
>> >> +static const struct acpi_device_id virtio_mmio_acpi_match[] =
{
>> >> +     { "LNRO0005", },
>> >> +     { }
>> >> +};
>> >
>> > Hmm - we have reserved QEMUXXXX in ASWG explicitly for this
purpose.
>> >
>> > Pater - do you think it's a good idea to change this before
QEMU 2.4
>> > is released?
>>
>> Shannon's call, I guess. I don't know enough about ACPI to say.
>> I thought these ACPI IDs were already fixed because they were
>> what the kernel was looking for...
>>
>> -- PMM
>
> Apparently not :)
>
We assigned LNRO in ASWG to avoid collisions with our prototypes/real
platforms so it makes sense to me to switch to QEMUXXXX.

I will submit a new patch if Shannon wants to switch to that form.

Graeme

On 28 July 2015 at 11:27, Michael S. Tsirkin <mst at redhat.com>
wrote:
> On Tue, Jul 28, 2015 at 11:12:33AM +0100, Peter Maydell wrote:
>> On 28 July 2015 at 11:08, Michael S. Tsirkin <mst at redhat.com>
wrote:
>> > On Tue, Jul 28, 2015 at 10:44:02AM +0100, Graeme Gregory wrote:
>> >> Added the match table and pointers for ACPI probing to the
driver.
>> >>
>> >> This uses the same identifier for virt devices as being used
for qemu
>> >> ARM64 ACPI support.
>> >>
>> >>
http://git.linaro.org/people/shannon.zhao/qemu.git/commit/d0bf1955a3ecbab4b51d46f8c5dda02b7e14a17e
>> >>
>> >> Signed-off-by: Graeme Gregory <graeme.gregory at
linaro.org>
>> >> +#ifdef CONFIG_ACPI
>> >> +static const struct acpi_device_id virtio_mmio_acpi_match[] =
{
>> >> +     { "LNRO0005", },
>> >> +     { }
>> >> +};
>> >
>> > Hmm - we have reserved QEMUXXXX in ASWG explicitly for this
purpose.
>> >
>> > Pater - do you think it's a good idea to change this before
QEMU 2.4
>> > is released?
>>
>> Shannon's call, I guess. I don't know enough about ACPI to say.
>> I thought these ACPI IDs were already fixed because they were
>> what the kernel was looking for...
> Apparently not :)
Mmm. I'm not terribly happy about stuff being in QEMU before the
ACPI spec for it has been finalised. We should not be picking
stuff randomly on the fly...

If we want to fix the ACPI IDs QEMU is using for 2.4 then we
really need to do that now (ie within the next day or two).

-- PMM