On Wed, Jul 02, 2014 at 05:02:07AM -0400, Gabriel L. Somlo wrote: > On Mon, Jun 30, 2014 at 08:21:43PM +0200, Alexander Graf wrote: > > > > > > > Am 30.06.2014 um 19:55 schrieb "Michael S. Tsirkin" <m...@redhat.com>: > > > > > >> On Mon, Jun 30, 2014 at 12:55:50PM -0400, Gabriel L. Somlo wrote: > > >> When running on PIIX (as opposed to q35), the stock OS X e1000 > > >> driver (AppleIntel8254XEthernet.kext) takes longer to load and > > >> activete, and will "miss" the link status change interrupt > > >> injected when the emulated "hardware" autonegotiation completes > > >> (see commit 39bb8ee737595e9b264d075dfcd7d86f4d3f1133). > > >> > > >> This patch extends the delay of the autonetotiation timer set up > > >> during set_phy_ctrl() to a value just large enough to work with > > >> the OS X driver. > > >> > > >> Signed-off-by: Gabriel Somlo <so...@cmu.edu> > > >> --- > > >> > > >> So, the loading OS X driver must take longer between its last > > >> write to the PHY_CTRL register and the time it starts looking > > >> for LSC interrupts, because at delay==500 it obviously misses > > >> the relevant interrupt. Making this 5500 (actually anything > > >> larger than 5300, but there's a bit of variation across OS X > > >> versions, so I rounded up a bit) has the timer fire after > > >> enough time has passed that the driver knows what to do when > > >> the interrupt from the network card fires... > > >> > > >> Thanks, > > >> Gabriel > > >> > > >> hw/net/e1000.c | 2 +- > > >> 1 file changed, 1 insertion(+), 1 deletion(-) > > >> > > >> diff --git a/hw/net/e1000.c b/hw/net/e1000.c > > >> index 2376910..2300477 100644 > > >> --- a/hw/net/e1000.c > > >> +++ b/hw/net/e1000.c > > >> @@ -209,7 +209,7 @@ set_phy_ctrl(E1000State *s, int index, uint16_t val) > > >> e1000_link_down(s); > > >> DBGOUT(PHY, "Start link auto negotiation\n"); > > >> timer_mod(s->autoneg_timer, > > >> - qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 500); > > >> + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 5500); > > >> } > > >> } > > > > > > > > > Besides being a bit hacky, it actually has a decent chance > > > to delay boot for guests. 500ms is probably the max we > > > can reasonably tolerate, even that is a bit high. > > > > Are you sure there's not just simply some irq unmasking event after 5500ms > > we don't handle properly? > > I poked around a bit, and the e1000 interrupt mask register is NOT the > problem (the LSC mask bit is clear at all times). If anything, maybe > the PIIX southbridge (or something further up "north") is masking PCI > interrupts (at least from e1000) until roughly 5500 ms into the boot > process ? Any ideas on how I could go about verifying this (without > access to the guest source, obviously :) ) would be very helpful... > > Thanks, > --Gabriel
Just poking around the spec I find more things we don't implement correctly wrt to auto-negotiation. For example, MII_SR_AUTONEG_CAPS isn't set, is it? Maybe that's why your guest doesn't work: it doesn't expect to get autonegotation at all? So I have a question: does your patch actually help any guests? If not, maybe we should defer it to after release, and try to clean up autonegotiation more thouroughly for 2.2? -- MST
