Re: [PATCH 12/13] ppc440_pcix: Don't use iomem for regs

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 4/7/23 11:37, BALATON Zoltan wrote:
> On Tue, 4 Jul 2023, Philippe Mathieu-Daudé wrote:
>> On 4/7/23 00:02, BALATON Zoltan wrote:
>>> The iomem memory region is better used for the PCI IO space but
>>> currently used for registers. Stop using it for that to allow this to
>>> be cleaned up in the next patch.
>>>
>>> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
>>> ---
>>>   hw/ppc/ppc440_pcix.c | 7 ++++---
>>>   1 file changed, 4 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/hw/ppc/ppc440_pcix.c b/hw/ppc/ppc440_pcix.c
>>> index adfecf1e76..ee2dc44f67 100644
>>> --- a/hw/ppc/ppc440_pcix.c
>>> +++ b/hw/ppc/ppc440_pcix.c
>>> @@ -484,6 +484,7 @@ static void ppc440_pcix_realize(DeviceState *dev, 
>>> Error **errp)
>>>       SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
>>>       PPC440PCIXState *s;
>>>       PCIHostState *h;
>>> +    MemoryRegion *regs = g_new(MemoryRegion, 1);
>>
>> Why not hold it within PPC440PCIXState?
> 
> Because it's never needed after this function.

But we can't free() it because it has to stay valid as long as
PPC440PCIXState is in use. So it seems to belong there.

> 
> Regards,
> BALATON Zoltan
> 
>>>       h = PCI_HOST_BRIDGE(dev);
>>>       s = PPC440_PCIX_HOST(dev);
>>> @@ -507,11 +508,11 @@ static void ppc440_pcix_realize(DeviceState 
>>> *dev, Error **errp)
>>>                             h, "pci-conf-idx", 4);
>>>       memory_region_init_io(&h->data_mem, OBJECT(s), 
>>> &pci_host_data_le_ops,
>>>                             h, "pci-conf-data", 4);
>>> -    memory_region_init_io(&s->iomem, OBJECT(s), &pci_reg_ops, s,
>>> -                          "pci.reg", PPC440_REG_SIZE);
>>> +    memory_region_init_io(regs, OBJECT(s), &pci_reg_ops, s, "pci-reg",
>>> +                          PPC440_REG_SIZE);
>>>       memory_region_add_subregion(&s->container, PCIC0_CFGADDR, 
>>> &h->conf_mem);
>>>       memory_region_add_subregion(&s->container, PCIC0_CFGDATA, 
>>> &h->data_mem);
>>> -    memory_region_add_subregion(&s->container, PPC440_REG_BASE, 
>>> &s->iomem);
>>> +    memory_region_add_subregion(&s->container, PPC440_REG_BASE, regs);
>>>       sysbus_init_mmio(sbd, &s->container);
>>>   }
>>>
>>
>>
>>