On Fri, Dec 3, 2021 at 1:54 PM Patrick Venture <vent...@google.com> wrote:
>
>
> On Fri, Dec 3, 2021 at 1:42 PM Philippe Mathieu-Daudé <f4...@amsat.org>
> wrote:
>
>> On 12/3/21 22:27, Patrick Venture wrote:
>> > The rx_active boolean change to true should always trigger a try_read
>> > call that flushes the queue.
>> >
>> > Signed-off-by: Patrick Venture <vent...@google.com>
>> > ---
>> > hw/net/npcm7xx_emc.c | 10 ++--------
>> > 1 file changed, 2 insertions(+), 8 deletions(-)
>> >
>> > diff --git a/hw/net/npcm7xx_emc.c b/hw/net/npcm7xx_emc.c
>> > index 7c892f820f..97522e6388 100644
>> > --- a/hw/net/npcm7xx_emc.c
>> > +++ b/hw/net/npcm7xx_emc.c
>> > @@ -581,13 +581,6 @@ static ssize_t emc_receive(NetClientState *nc,
>> const uint8_t *buf, size_t len1)
>> > return len;
>> > }
>> >
>> > -static void emc_try_receive_next_packet(NPCM7xxEMCState *emc)
>> > -{
>> > - if (emc_can_receive(qemu_get_queue(emc->nic))) {
>> > - qemu_flush_queued_packets(qemu_get_queue(emc->nic));
>> > - }
>> > -}
>>
>> What about modifying as emc_flush_rx() or emc_receive_and_flush()
>> helper instead?
>>
>> static void emc_flush_rx(NPCM7xxEMCState *emc)
>> {
>> emc->rx_active = true;
>> qemu_flush_queued_packets(qemu_get_queue(emc->nic));
>> }
>>
>
> I'm ok with that idea, although I'm less fond that it _hides_ the
> rx_active=true. There is an emc_halt_rx that hides rx_active=false, so one
> could argue it's not an issue. Looking at ftgmac100, it mostly just calls
> the qemu_flush_queued_packets inline where it needs it. So given the prior
> art, I'm more inclined to leave this as a two-line pair, versus collapsing
> it into a method. Mostly because I don't anticipate this call being made
> from any other places, so it's not a "growing" device. The method
> originally was emc_try_receive_next_packet, which didn't do anything more
> than a no-op check and the queue_flush. The new method would move the
> rx_active setting from the call that deliberately controls it (the register
> change) into a subordinate method...
>
> Beyond all that, I think it's fine either way. Feel free to push back and
> I'll make the change.
>
I figured why not :) And just made the change and sent out a v2.
>
>> > static uint64_t npcm7xx_emc_read(void *opaque, hwaddr offset, unsigned
>> size)
>> > {
>> > NPCM7xxEMCState *emc = opaque;
>> > @@ -704,6 +697,7 @@ static void npcm7xx_emc_write(void *opaque, hwaddr
>> offset,
>> > }
>> > if (value & REG_MCMDR_RXON) {
>> > emc->rx_active = true;
>> > + qemu_flush_queued_packets(qemu_get_queue(emc->nic));
>> > } else {
>> > emc_halt_rx(emc, 0);
>> > }
>> > @@ -740,7 +734,7 @@ static void npcm7xx_emc_write(void *opaque, hwaddr
>> offset,
>> > case REG_RSDR:
>> > if (emc->regs[REG_MCMDR] & REG_MCMDR_RXON) {
>> > emc->rx_active = true;
>> > - emc_try_receive_next_packet(emc);
>> > + qemu_flush_queued_packets(qemu_get_queue(emc->nic));
>> > }
>> > break;
>> > case REG_MIIDA:
>> >
>>
>>
