net: fec: Refactor MAC reset to function

[ Upstream commit 67800d296191d0a9bde0a7776f99ca1ddfa0fc26 ]

The core is reset both in `fec_restart()` (called on link-up) and
`fec_stop()` (going to sleep, driver remove etc.). These two functions
had their separate implementations, which was at first only a register
write and a `udelay()` (and the accompanying block comment). However,
since then we got soft-reset (MAC disable) and Wake-on-LAN support, which
meant that these implementations diverged, often causing bugs.

For instance, as of now, `fec_stop()` does not check for
`FEC_QUIRK_NO_HARD_RESET`, meaning the MII/RMII mode is cleared on eg.
a PM power-down event; and `fec_restart()` missed the refactor renaming
the "magic" constant `1` to `FEC_ECR_RESET`.

To harmonize current implementations, and eliminate this source of
potential future bugs, refactor implementation to a common function.

Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Csókás, Bence <csokas.bence@prolan.hu>
Link: https://patch.msgid.link/20250207121255.161146-2-csokas.bence@prolan.hu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Csókás, Bence
2025-02-07 13:12:55 +01:00
committed by Greg Kroah-Hartman
parent 2caf52c072
commit 6758d09763

View File

@@ -1079,6 +1079,29 @@ static void fec_enet_enable_ring(struct net_device *ndev)
}
}
/* Whack a reset. We should wait for this.
* For i.MX6SX SOC, enet use AXI bus, we use disable MAC
* instead of reset MAC itself.
*/
static void fec_ctrl_reset(struct fec_enet_private *fep, bool allow_wol)
{
u32 val;
if (!allow_wol || !(fep->wol_flag & FEC_WOL_FLAG_SLEEP_ON)) {
if (fep->quirks & FEC_QUIRK_HAS_MULTI_QUEUES ||
((fep->quirks & FEC_QUIRK_NO_HARD_RESET) && fep->link)) {
writel(0, fep->hwp + FEC_ECNTRL);
} else {
writel(FEC_ECR_RESET, fep->hwp + FEC_ECNTRL);
udelay(10);
}
} else {
val = readl(fep->hwp + FEC_ECNTRL);
val |= (FEC_ECR_MAGICEN | FEC_ECR_SLEEP);
writel(val, fep->hwp + FEC_ECNTRL);
}
}
/*
* This function is called to start or restart the FEC during a link
* change, transmit timeout, or to reconfigure the FEC. The network
@@ -1095,17 +1118,7 @@ fec_restart(struct net_device *ndev)
if (fep->bufdesc_ex)
fec_ptp_save_state(fep);
/* Whack a reset. We should wait for this.
* For i.MX6SX SOC, enet use AXI bus, we use disable MAC
* instead of reset MAC itself.
*/
if (fep->quirks & FEC_QUIRK_HAS_MULTI_QUEUES ||
((fep->quirks & FEC_QUIRK_NO_HARD_RESET) && fep->link)) {
writel(0, fep->hwp + FEC_ECNTRL);
} else {
writel(1, fep->hwp + FEC_ECNTRL);
udelay(10);
}
fec_ctrl_reset(fep, false);
/*
* enet-mac reset will reset mac address registers too,
@@ -1359,22 +1372,7 @@ fec_stop(struct net_device *ndev)
if (fep->bufdesc_ex)
fec_ptp_save_state(fep);
/* Whack a reset. We should wait for this.
* For i.MX6SX SOC, enet use AXI bus, we use disable MAC
* instead of reset MAC itself.
*/
if (!(fep->wol_flag & FEC_WOL_FLAG_SLEEP_ON)) {
if (fep->quirks & FEC_QUIRK_HAS_MULTI_QUEUES) {
writel(0, fep->hwp + FEC_ECNTRL);
} else {
writel(FEC_ECR_RESET, fep->hwp + FEC_ECNTRL);
udelay(10);
}
} else {
val = readl(fep->hwp + FEC_ECNTRL);
val |= (FEC_ECR_MAGICEN | FEC_ECR_SLEEP);
writel(val, fep->hwp + FEC_ECNTRL);
}
fec_ctrl_reset(fep, true);
writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);
writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);