Re: [Qemu-devel] [RESEND][PATCH 3/9] microdrive: qdevify

[Dmitry Eremin-Solenikov]

On 5/16/11, andrzej zaborowski <address@hidden> wrote:
> On 16 May 2011 06:54, Dmitry Eremin-Solenikov <address@hidden> wrote:
>> Hello,
>>
>> On 5/16/11, andrzej zaborowski <address@hidden> wrote:
>>> On 25 April 2011 11:06, Dmitry Eremin-Solenikov <address@hidden>
>>> wrote:
>>>> Switch dscm1xxxx microdrive driver to use qdev infrastructure.
>>>> ---
>>>>  hw/ide/microdrive.c |   49
>>>> +++++++++++++++++++++++++++++++++++++++----------
>>>>  hw/pcmcia.h         |    2 +-
>>>>  hw/spitz.c          |    5 ++++-
>>>>  hw/tosa.c           |    5 ++++-
>>>>  4 files changed, 48 insertions(+), 13 deletions(-)
>>>>
>>>> diff --git a/hw/ide/microdrive.c b/hw/ide/microdrive.c
>>>> index 9fbbf0e..7692603 100644
>>>> --- a/hw/ide/microdrive.c
>>>> +++ b/hw/ide/microdrive.c
>>>> @@ -38,8 +38,8 @@
>>>>
>>>>  /* DSCM-1XXXX Microdrive hard disk with CF+ II / PCMCIA interface.  */
>>>>  typedef struct {
>>>> -    IDEBus bus;
>>>>     PCMCIACardState card;
>>>> +    IDEBus bus;
>>>>     uint32_t attr_base;
>>>>     uint32_t io_base;
>>>>
>>>> @@ -529,22 +529,51 @@ static int dscm1xxxx_detach(void *opaque)
>>>>     return 0;
>>>>  }
>>>>
>>>> -PCMCIACardState *dscm1xxxx_init(DriveInfo *bdrv)
>>>> +PCMCIACardState *dscm1xxxx_init(PCMCIASocket *socket, DriveInfo *bdrv)
>>>
>>> This looks like a regression that you have to pass the socket when
>>> creating a PCMCIA card.  I consider it an advantage of the current
>>> code that pcmcia cards are hotswappable.  Can we keep that with
>>> qdevification?  Otherwise is there a gain from the qdevification?
>>
>> Socket is required, as we have to know the QBus before creating the
>> device on it.
>
> Let's skip the qbusification then.  It seems that qbus is a wrong
> choice for pcmcia and there are no new features or bugs fixed by the
> conversion, it's code motion?  I also don't see why the socket
> structure should be needed at the creation time of a PCI device for
> example, the BusInfo should be enough logically.

Major point for qbus'ification was ability to create PCMCIA devices from
command line/via other management tools. This would also allow us e.g.
to move microdrive driver to common ide parts, etc.

For creation of a DeviceState via qdev_create you need BusState (which
is a part of PCMCIASocket). Of course I can make one global QBus for
all PCMCIA devices and make some artificial hacks to attach/detach cards
to artificial sockets, but this seems like a hack.

-- 
With best wishes
Dmitry