Re: [PATCH 13/13] hw/ide: Extract bmdma_clear_status()

[Bernhard Beschow]

Am 23. April 2023 10:40:50 UTC schrieb BALATON Zoltan <balaton@eik.bme.hu>:
>On Sun, 23 Apr 2023, Bernhard Beschow wrote:
>> Am 22. April 2023 21:26:00 UTC schrieb BALATON Zoltan <balaton@eik.bme.hu>:
>>> On Sat, 22 Apr 2023, Bernhard Beschow wrote:
>>>> Extract bmdma_clear_status() mirroring bmdma_cmd_writeb().
>>> 
>>> Is adding a trace point useful? This is called from places that already 
>>> have traces so I don't think we need another separate trace point here.
>> 
>> Adding a trace point was my original motivation to have this function. Then 
>> I realized that extracting the code in a dedicated function is a merit in 
>> itself. The trace point is a leftover, so I'll remove it.
>> 
>>> Also the names don't match but maybe rename function to bmdma_update_status 
>>> instead as it is more what it does.
>> 
>> The status attribute models a w1c-style register. Writing to it can only 
>> clear bits, hence the name. Indeed I originally named the function 
>> bmdma_update_status() but thought it was too vague. I'm open to suggestions 
>> though.
>
>The function seems to clear bits 1-2 but set bits 5-6 so it it has some write 
>1 to clear and some read write bits. Therefore naming the function clear when 
>it can also set bits is not quite right so I think update is better.

Convinced. I'll rename to bmdma_update_status() in the next iteration.

Best regards,
Bernhard

>
>Regards,
>BALATON Zoltan
>
>>>> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>>>> ---
>>>> include/hw/ide/pci.h |  1 +
>>>> hw/ide/cmd646.c      |  2 +-
>>>> hw/ide/pci.c         |  7 +++++++
>>>> hw/ide/piix.c        |  2 +-
>>>> hw/ide/sii3112.c     | 12 +++++-------
>>>> hw/ide/via.c         |  2 +-
>>>> hw/ide/trace-events  |  1 +
>>>> 7 files changed, 17 insertions(+), 10 deletions(-)
>>>> 
>>>> diff --git a/include/hw/ide/pci.h b/include/hw/ide/pci.h
>>>> index 81e0370202..6a286ad307 100644
>>>> --- a/include/hw/ide/pci.h
>>>> +++ b/include/hw/ide/pci.h
>>>> @@ -59,6 +59,7 @@ struct PCIIDEState {
>>>> void bmdma_init(IDEBus *bus, BMDMAState *bm, PCIIDEState *d);
>>>> void bmdma_init_ops(PCIIDEState *d, const MemoryRegionOps *bmdma_ops);
>>>> void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val);
>>>> +void bmdma_clear_status(BMDMAState *bm, uint32_t val);
>>>> void pci_ide_create_devs(PCIDevice *dev);
>>>> 
>>>> #endif
>>>> diff --git a/hw/ide/cmd646.c b/hw/ide/cmd646.c
>>>> index b9d005a357..973c3ff0dc 100644
>>>> --- a/hw/ide/cmd646.c
>>>> +++ b/hw/ide/cmd646.c
>>>> @@ -144,7 +144,7 @@ static void bmdma_write(void *opaque, hwaddr addr,
>>>>         cmd646_update_irq(pci_dev);
>>>>         break;
>>>>     case 2:
>>>> -        bm->status = (val & 0x60) | (bm->status & 1) | (bm->status & ~val 
>>>> & 0x06);
>>>> +        bmdma_clear_status(bm, val);
>>>>         break;
>>>>     case 3:
>>>>         if (bm == &bm->pci_dev->bmdma[0]) {
>>>> diff --git a/hw/ide/pci.c b/hw/ide/pci.c
>>>> index 3539b162b7..4aa06be7c6 100644
>>>> --- a/hw/ide/pci.c
>>>> +++ b/hw/ide/pci.c
>>>> @@ -318,6 +318,13 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val)
>>>>     bm->cmd = val & 0x09;
>>>> }
>>>> 
>>>> +void bmdma_clear_status(BMDMAState *bm, uint32_t val)
>>>> +{
>>>> +    trace_bmdma_update_status(val);
>>>> +
>>>> +    bm->status = (val & 0x60) | (bm->status & BM_STATUS_DMAING) | 
>>>> (bm->status & ~val & 0x06);
>>>> +}
>>>> +
>>>> static uint64_t bmdma_addr_read(void *opaque, hwaddr addr,
>>>>                                 unsigned width)
>>>> {
>>>> diff --git a/hw/ide/piix.c b/hw/ide/piix.c
>>>> index 406a67fa0f..9eab615e35 100644
>>>> --- a/hw/ide/piix.c
>>>> +++ b/hw/ide/piix.c
>>>> @@ -76,7 +76,7 @@ static void bmdma_write(void *opaque, hwaddr addr,
>>>>         bmdma_cmd_writeb(bm, val);
>>>>         break;
>>>>     case 2:
>>>> -        bm->status = (val & 0x60) | (bm->status & 1) | (bm->status & ~val 
>>>> & 0x06);
>>>> +        bmdma_clear_status(bm, val);
>>>>         break;
>>>>     }
>>>> }
>>>> diff --git a/hw/ide/sii3112.c b/hw/ide/sii3112.c
>>>> index 373c0dd1ee..1180ff55e7 100644
>>>> --- a/hw/ide/sii3112.c
>>>> +++ b/hw/ide/sii3112.c
>>>> @@ -66,7 +66,7 @@ static void sii3112_bmdma_write(void *opaque, hwaddr 
>>>> addr,
>>>>                                 uint64_t val, unsigned int size)
>>>> {
>>>>     BMDMAState *bm = opaque;
>>>> -    SiI3112PCIState *d = SII3112_PCI(bm->pci_dev);
>>>> +    SiI3112PCIState *s = SII3112_PCI(bm->pci_dev);
>>>>     int i = (bm == &bm->pci_dev->bmdma[0]) ? 0 : 1;
>>>> 
>>>>     trace_sii3112_bmdma_write(size, addr, val);
>>>> @@ -75,10 +75,10 @@ static void sii3112_bmdma_write(void *opaque, hwaddr 
>>>> addr,
>>>>         bmdma_cmd_writeb(bm, val);
>>>>         break;
>>>>     case 0x01:
>>>> -        d->regs[i].swdata = val & 0x3f;
>>>> +        s->regs[i].swdata = val & 0x3f;
>>>>         break;
>>>>     case 0x02:
>>>> -        bm->status = (val & 0x60) | (bm->status & 1) | (bm->status & ~val 
>>>> & 6);
>>>> +        bmdma_clear_status(bm, val);
>>>>         break;
>>>>     default:
>>>>         break;
>>>> @@ -160,8 +160,7 @@ static void sii3112_reg_write(void *opaque, hwaddr 
>>>> addr,
>>>>         d->regs[0].swdata = val & 0x3f;
>>>>         break;
>>>>     case 0x12:
>>>> -        d->i.bmdma[0].status = (val & 0x60) | (d->i.bmdma[0].status & 1) |
>>>> -                               (d->i.bmdma[0].status & ~val & 6);
>>>> +        bmdma_clear_status(&d->i.bmdma[0], val);
>>>>         break;
>>>>     case 0x18:
>>>>         bmdma_cmd_writeb(&d->i.bmdma[1], val);
>>>> @@ -170,8 +169,7 @@ static void sii3112_reg_write(void *opaque, hwaddr 
>>>> addr,
>>>>         d->regs[1].swdata = val & 0x3f;
>>>>         break;
>>>>     case 0x1a:
>>>> -        d->i.bmdma[1].status = (val & 0x60) | (d->i.bmdma[1].status & 1) |
>>>> -                               (d->i.bmdma[1].status & ~val & 6);
>>>> +        bmdma_clear_status(&d->i.bmdma[1], val);
>>>>         break;
>>>>     case 0x100:
>>>>         d->regs[0].scontrol = val & 0xfff;
>>>> diff --git a/hw/ide/via.c b/hw/ide/via.c
>>>> index 35dd97e49b..afb97f302a 100644
>>>> --- a/hw/ide/via.c
>>>> +++ b/hw/ide/via.c
>>>> @@ -75,7 +75,7 @@ static void bmdma_write(void *opaque, hwaddr addr,
>>>>         bmdma_cmd_writeb(bm, val);
>>>>         break;
>>>>     case 2:
>>>> -        bm->status = (val & 0x60) | (bm->status & 1) | (bm->status & ~val 
>>>> & 0x06);
>>>> +        bmdma_clear_status(bm, val);
>>>>         break;
>>>>     default:;
>>>>     }
>>>> diff --git a/hw/ide/trace-events b/hw/ide/trace-events
>>>> index a479525e38..d219c64b61 100644
>>>> --- a/hw/ide/trace-events
>>>> +++ b/hw/ide/trace-events
>>>> @@ -30,6 +30,7 @@ bmdma_write_cmd646(uint64_t addr, uint64_t val) "bmdma: 
>>>> writeb 0x%"PRIx64" : 0x%
>>>> # pci.c
>>>> bmdma_reset(void) ""
>>>> bmdma_cmd_writeb(uint32_t val) "val: 0x%08x"
>>>> +bmdma_update_status(uint32_t val) "val: 0x%08x"
>>>> bmdma_addr_read(uint64_t data) "data: 0x%016"PRIx64
>>>> bmdma_addr_write(uint64_t data) "data: 0x%016"PRIx64
>>>> 
>>>> 
>> 
>>