On Mon, Jan 22, 2018 at 3:48 AM, Peter Maydell <peter.mayd...@linaro.org> wrote: > On 13 January 2018 at 11:34, Jean-Christophe Dubois <j...@tribudubois.net> > wrote: >> The actual imx_eth_enable_rx() function is buggy. >> >> It updates s->regs[ENET_RDAR] after calling qemu_flush_queued_packets(). >> >> qemu_flush_queued_packets() is going to call imx_XXX_receive() which itself >> is going to call imx_eth_enable_rx(). >> >> By updating s->regs[ENET_RDAR] after calling qemu_flush_queued_packets() >> we end up updating the register with an outdated value which might >> lead to disabling the receive function in the i.MX FEC/ENET device. >> >> This patch change the place where the register update is done so that the >> register value stays up to date and the receive function can keep >> running. >> >> Reported-by: Fyleo <fyle...@gmail.com> >> Tested-by: Fyleo <fyle...@gmail.com> >> Signed-off-by: Jean-Christophe Dubois <j...@tribudubois.net> >> --- > > Andrey, do you have an opinion on this patch, since you've been > looking at i.MX code recently? >
The rationale makes sense to me and patch looks like a good cleanup in general, so FWIW: Reviewed-by: Andrey Smirnov <andrew.smir...@gmail.com> I also gave it a spin against my i.MX7 changes with doing basic things like ping and scp of 1GB file, so I can give my: Tested-by: Andrey Smirnov <andrew.smir...@gmail.com> for that. Thanks, Andrey Smirnov >> Change since v1: >> 1. Rebase the patch on the updated master branch >> >> hw/net/imx_fec.c | 8 ++------ >> 1 file changed, 2 insertions(+), 6 deletions(-) >> >> diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c >> index 4fb48f62ba..9506f9b69f 100644 >> --- a/hw/net/imx_fec.c >> +++ b/hw/net/imx_fec.c >> @@ -595,19 +595,16 @@ static void imx_eth_do_tx(IMXFECState *s, uint32_t >> index) >> static void imx_eth_enable_rx(IMXFECState *s, bool flush) >> { >> IMXFECBufDesc bd; >> - bool rx_ring_full; >> >> imx_fec_read_bd(&bd, s->rx_descriptor); >> >> - rx_ring_full = !(bd.flags & ENET_BD_E); >> + s->regs[ENET_RDAR] = (bd.flags & ENET_BD_E) ? ENET_RDAR_RDAR : 0; >> >> - if (rx_ring_full) { >> + if (!s->regs[ENET_RDAR]) { >> FEC_PRINTF("RX buffer full\n"); >> } else if (flush) { >> qemu_flush_queued_packets(qemu_get_queue(s->nic)); >> } >> - >> - s->regs[ENET_RDAR] = rx_ring_full ? 0 : ENET_RDAR_RDAR; >> } >> >> static void imx_eth_reset(DeviceState *d) >> @@ -866,7 +863,6 @@ static void imx_eth_write(void *opaque, hwaddr offset, >> uint64_t value, >> case ENET_RDAR: >> if (s->regs[ENET_ECR] & ENET_ECR_ETHEREN) { >> if (!s->regs[index]) { >> - s->regs[index] = ENET_RDAR_RDAR; >> imx_eth_enable_rx(s, true); >> } >> } else { >> -- >> 2.14.1 > > Reviewed-by: Peter Maydell <peter.mayd...@linaro.org> > > thanks > -- PMM