Commit 6623d214 authored by Linus Ziegert's avatar Linus Ziegert Committed by Peter Maydell
Browse files

net/cadence_gem: Set PHY autonegotiation restart status 

The Linux kernel PHY driver sets AN_RESTART in the BMCR of the
PHY when autonegotiation is started.
Recently the kernel started to read back the PHY's AN_RESTART
bit and now checks whether the autonegotiation is complete and
the bit was cleared [1]. Otherwise the link status is down.

The emulated PHY needs to clear AN_RESTART immediately to inform
the kernel driver about the completion of autonegotiation phase.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c36757eb9dee



Signed-off-by: default avatarLinus Ziegert <linus.ziegert+qemu@holoplot.com>
Reviewed-by: default avatarAlistair Francis <alistair.francis@wdc.com>
Message-id: 20191104181604.21943-1-linus.ziegert+qemu@holoplot.com
Cc: qemu-stable@nongnu.org
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parent 3a6606c7

hw/net/cadence_gem.c

+5 −4
Original line number Diff line number Diff line
@@ -274,6 +274,7 @@ 
#define PHY_REG_CONTROL_RST       0x8000

#define PHY_REG_CONTROL_LOOP      0x4000

#define PHY_REG_CONTROL_ANEG      0x1000

#define PHY_REG_CONTROL_ANRESTART 0x0200



#define PHY_REG_STATUS_LINK     0x0004

#define PHY_REG_STATUS_ANEGCMPL 0x0020
@@ -1345,7 +1346,7 @@ static void gem_phy_write(CadenceGEMState *s, unsigned reg_num, uint16_t val) 
        }

        if (val & PHY_REG_CONTROL_ANEG) {

            /* Complete autonegotiation immediately */

            val &= ~PHY_REG_CONTROL_ANEG;

            val &= ~(PHY_REG_CONTROL_ANEG | PHY_REG_CONTROL_ANRESTART);

            s->phy_regs[PHY_REG_STATUS] |= PHY_REG_STATUS_ANEGCMPL;

        }

        if (val & PHY_REG_CONTROL_LOOP) {