Re: [Qemu-devel] [PATCH v3 2/2] ahci: add support for non-PCI based controllers

[Alexander Graf]

On 05.01.2012, at 15:16, Andreas Färber wrote:

> Am 05.01.2012 14:52, schrieb Mark Langsdorf:
>> From: Rob Herring <address@hidden>
>> 
>> Add support for ahci on sysbus.
>> 
>> Signed-off-by: Rob Herring <address@hidden>
>> Signed-off-by: Mark Langsdorf <address@hidden>
>> ---
>> Changes from v1, v2
>>      Corrected indentation of PlatAHCIState members
>>      Made plat_ahci_info into a single structure, not a list
>> 
>> hw/ide/ahci.c |   31 +++++++++++++++++++++++++++++++
>> 1 files changed, 31 insertions(+), 0 deletions(-)
>> 
>> diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
>> index 135d0ee..f052e55 100644
>> --- a/hw/ide/ahci.c
>> +++ b/hw/ide/ahci.c
>> @@ -25,6 +25,7 @@
>> #include <hw/msi.h>
>> #include <hw/pc.h>
>> #include <hw/pci.h>
>> +#include <hw/sysbus.h>
>> 
>> #include "monitor.h"
>> #include "dma.h"
>> @@ -1214,3 +1215,33 @@ void ahci_reset(void *opaque)
>>         ahci_reset_port(s, i);
>>     }
>> }
>> +
>> +typedef struct PlatAHCIState {
>> +    SysBusDevice busdev;
>> +    AHCIState ahci;
>> +} PlatAHCIState;
>> +
>> +static int plat_ahci_init(SysBusDevice *dev)
>> +{
>> +    PlatAHCIState *s = FROM_SYSBUS(PlatAHCIState, dev);
>> +    ahci_init(&s->ahci, &dev->qdev, 1);
>> +
>> +    sysbus_init_mmio(dev, &s->ahci.mem);
>> +    sysbus_init_irq(dev, &s->ahci.irq);

It's still unclear to me how you connect an irq line on the command line. How 
do you instantiate this device?

>> +
>> +    qemu_register_reset(ahci_reset, &s->ahci);
>> +    return 0;
>> +}
>> +
>> +static SysBusDeviceInfo plat_ahci_info = {
>> +    .qdev.name    = "plat-ahci",
> 
> The commit message does not given an indication where "plat" comes from
> - is that an ARM device name?

"plat" here means "platform device". I'm not sure I like the naming though. 
Basically it's a sysbus version of AHCI, similar to how virtio-mmio is a sysbus 
version of virtio.

How about "sysbus-ahci"?

> 
>> +    .qdev.size    = sizeof(PlatAHCIState),
>> +    .init         = plat_ahci_init,
>> +};
>> +
>> +static void plat_ahci_register(void)
>> +{
>> +    sysbus_register_withprop(&plat_ahci_info);
>> +}
>> +device_init(plat_ahci_register);
>> +
> 
> Please move the empty line to above the device_init().
> 
> Does this patch actually make something work? If yes, please state so,
> including usage instructions. If not, then I would suggest to hold this
> one back and to send it together with any follow-on patches that wire it
> up on some machine.

You can always just create the device manually with -device and hook it up in 
the guest device tree or machine description manually.

However the question still stands: Have you verified this code works?


Alex