Re: [PATCH 1/1] virtio-ccw: clarifications

Cornelia Huck <> writes:
> - further qualify bit numbering
> - specify summary indicator contents
> - drop early printk spec; it is only a hack that was never used upstream
>
> Reported-by: Thomas Huth <>
> Signed-off-by: Cornelia Huck <>

OK, thanks.

Because we have to track feedback, I've been recording them inside the
SVN tree.  I've just split it out into a feedback/ directory, and your
patch is in feedback/2.txt.

We'll decide on each one at the next meeting (I expect we'll just apply
them).

Thanks,
Rusty.

> ---
>  content.tex |   10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/content.tex b/content.tex
> index 803615d..0a94c07 100644
> --- a/content.tex
> +++ b/content.tex
> @@ -2174,7 +2174,8 @@ summary_indicator contains the guest address of the 8 bit summary
>  indicator.
>  indicator contains the guest address of an area wherin the indicators
>  for the devices are contained, starting at bit_nr, one bit per
> -virtqueue of the device. Bit numbers start at the left.
> +virtqueue of the device. Bit numbers start at the left, i.e. the most
> +significant bit in the first byte is assigned the bit number 0.
>  isc contains the I/O interruption subclass to be used for the adapter
>  I/O interrupt. It may be different from the isc used by the proxy
>  virtio-ccw device's subchannel.
> @@ -2224,7 +2225,7 @@ host->guest notification about virtqueue activity.
>  
>  For notifying the driver of virtqueue buffers, the device sets the
>  bit in the guest-provided indicator area at the corresponding offset.
> -The guest-provided summary indicator is also set. An adapter I/O
> +The guest-provided summary indicator is set to 0x01. An adapter I/O
>  interrupt for the corresponding interruption subclass is generated.
>  The device SHOULD only generate an adapter I/O interrupt if the
>  summary indicator had not been set prior to notification. The driver
> @@ -2273,11 +2274,6 @@ should be passed in GPR4 for the next notification:
>                                   info->cookie);
>  \end{lstlisting}
>  
> -\subsubsection{Early printk for Virtio Consoles}\label{sec:Virtio Transport Options / Virtio over channel I/O / Device Operation / Early printk for Virtio Consoles}
> -
> -For the early printk mechanism, diagnose 0x500 with subcode 0 is
> -used.
> -
>  \subsubsection{Resetting Devices}\label{sec:Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices}
>  
>  In order to reset a device, a driver sends the
> -- 
> 1.7.9.5