On Mon, Aug 04, 2014 at 07:08:01PM +0100, Pawel Moll wrote:
> Those changes do not add nor remove any features and constitutes
> only error correction and editorial changes. This one seems to be borderline. > * Extra clarifications for QueueReady and ConfigGeneration > * Re-added alignment requirement section - it existed in the
>
original version of the spec, so no extra limitations here. What is an "original version"? I could not find this in draft 01.
> Signed-off-by: Pawel Moll <> > ---
> content.tex
21 ++++++++++++++++
-----
> 1 file changed, 16 insertions(+), 5 deletions(-) >
> diff --git a/content.tex b/content.tex
> index 17ba3b8..769bef2 100644 > --- a/content.tex > +++ b/content.tex > @@ -1997,8 +1997,8 @@ All register values are organized as Little Endian. >
}
>
hline
>
mmioreg{QueueReady}{Virtual queue ready bit}{0x044}{RW}{% > -
Writing one (0x1) to this register notifies the device that the > -
virtual queue is ready to be used. Reading from this register > +
Writing one (0x1) to this register notifies the device that it can > +
execute requests from this virtual queue. Reading from this register
>
returns the last value written to it. Both read and write
>
accesses apply to the queue selected by writing to field{QueueSel}. >
} > @@ -2058,7 +2058,11 @@ All register values are organized as Little Endian. >
}
>
hline
>
mmioreg{ConfigGeneration}{Configuration atomicity value}{0x0fc}{R}{ > -
Changes every time the configuration noticeably changes (see
ef {sec:Basic Facilities of a Virtio Device / Device Configuration Space}. > +
Reading from this register returns a value describing a version of the device-specific configuration (see field{Config}). > +
The driver can then access the configuration space and then read field{ConfigGeneration} again. > +
If no part of the configuration space has changed, field{ConfigGeneration} returns the same value. > +
If the value is different, the configuration space access was not atomic and the driver must perform the operation again. > +
See also
ef {sec:Basic Facilities of a Virtio Device / Device Configuration Space}. >
}
>
hline
>
mmioreg{Config}{Configuration space}{0x100+}{RW}{ > @@ -2083,10 +2087,12 @@ do not represent events which took place MUST be zero.
> Upon reset, the device MUST clear all bits in field{InterruptStatus} and ready bits in the
> field{QueueReady} register for all queues in the device. >
> -The device MUST change field{ConfigGeneration} if there is any risk of a > -device seeing an inconsistent configuration state, but it MAY only change the value > +The device MUST change value returned in field{ConfigGeneration} if there is any risk of a > +driver seeing an inconsistent configuration state, but it MAY only change the value
> after a configuration read operation. "MAY only" is really confusing. You are using MAY here to describe a mandatory requirement. Can be re-written with "MUST NOT"? Also, surely reset changes this field to 0?
>
> +The device MUST NOT access virtual queue contents when field{QueueReady} is zero (0x0). > +
> drivernormative{subsubsection}{MMIO Device Register Layout}{Virtio Transport Options / Virtio Over MMIO / MMIO Device Register Layout}
> The driver MUST NOT access memory locations not described in the
> table
ef{tab:Virtio Trasport Options / Virtio Over MMIO / MMIO Device Register Layout} > @@ -2094,6 +2100,11 @@ table
ef{tab:Virtio Trasport Options / Virtio Over MMIO / MMIO Device Register
> MUST NOT write to the read-only registers (direction R) and
> MUST NOT read from the write-only registers (direction W). >
> +The driver MUST only use 32 bit wide and aligned reads and writes to access the control registers > +described in table
ef{tab:Virtio Trasport Options / Virtio Over MMIO / MMIO Device Register Layout}. OK this was kind of implied all the time ... you think adding this text is error correction? > +The driver MAY use other accesses for the device-specific configuration space, > +depending on the device type. > + Why are you adding this option? If there's a 4 byte register it is a pain for devices to support 1 byte accesses, and we gain nothing from it.
> The driver MUST ignore a device with field{MagicValue} which is not 0x74726976,
> although it MAY report an error. >
> --
> 1.9.1 > > >
---------------------------------------------------------------------
> To unsubscribe from this mail list, you must leave the OASIS TC that
> generates this mail. Follow this link to all your TCs in OASIS at:
> https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php
