Re: [Qemu-devel] [PATCH 00/19] Declare device little or big endian

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 8/26/19 4:21 PM, Tony Nguyen wrote:
> This series is an attempt to re-declare devices with DEVICE_NATIVE_ENDIAN as
> DEVICE_LITTLE_ENDIAN or DEVICE_BIG_ENDIAN.
> 
> This clean up was split out from an earlier series which collapsed byte swaps
> along the I/O path.
> 
> On Wed, 7 Aug 2019 at 12:42, Paolo Bonzini wrote:
>> On 07/08/19 10:31, tony.nguyen@bt wrote:
>>>
>>> Device realizing code with MemorRegionOps endianness as
>>> DEVICE_NATIVE_ENDIAN is not common code.
>>>
>>> Corrected devices were identified by making the declaration of
>>> DEVICE_NATIVE_ENDIAN conditional upon NEED_CPU_H and then listing
>>> what failed to compile.
>>
>> The general approach makes sense.  However, most of these should not be
>> DEVICE_NATIVE_ENDIAN.  I can help with some of them.
> 
> On Fri, 16 Aug 2019 at 13:02, Peter Maydell wrote:
>> OTOH it's worth noting that it's quite likely that most of
>> the implementations of these DEVICE_NATIVE_ENDIAN devices
>> picked it in an equally naive way, by just copying some other
>> device's code...
> 
> Approach this in two steps.
> 
> 1. Naively. For each device declared with DEVICE_NATIVE_ENDIAN, find the set of
> targets from the set of target/hw/*/device.o.
> 
> If the set of targets are all little or all big endian, re-declare
> as DEVICE_LITTLE_ENDIAN or DEVICE_BIG_ENDIAN respectively.
> 
> 2. Manually. Inspect with heuristics (thanks Paolo):
> - if not used, re-declare as DEVICE_HOST_ENDIAN.
> - if max/min size=1, re-declare as DEVICE_HOST_ENDIAN.
> - if just a bit bucket, re-declare as DEVICE_HOST_ENDIAN
> - if PCI, re-declare as DEVICE_LITTLE_ENDIAN.
> - if for {ARM|unicore32} only, re-declare as DEVICE_LITTLE_ENDIAN.
> - if for SPARC only, re-declare as DEVICE_BIG_ENDIAN.

Maybe this list is better to split your patches.

Which are the 'not used' ones?

TYPE_TPCI200 (from IndustryPack) can go with PCI.

You can put all the PrimeCell devices together (eventually with the 
other ARM devices):

  hw/audio/pl041.c
  hw/char/pl011.c
  hw/display/pl110.c
  hw/dma/pl080.c
  hw/dma/pl330.c
  hw/gpio/pl061.c
  hw/input/pl050.c
  hw/intc/pl190.c
  hw/sd/pl181.c
  hw/ssi/pl022.c
  hw/timer/pl031.c