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

[Bernhard Beschow <shentey@gmail.com>]

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.

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
>> 
>>