[SRU] [Bionic/OEM-A] [PATCH 1/2] net: aquantia: Regression on reset with 1.x firmware

[Kai-Heng Feng]

From: Igor Russkikh <igor.russkikh at aquantia.com>

BugLink: https://bugs.launchpad.net/bugs/1767088

On ASUS XG-C100C with 1.5.44 firmware a special mode called "dirty wake"
is active. With this mode when motherboard gets powered (but no poweron
happens yet), NIC automatically enables powersave link and watches
for WOL packet.
This normally allows to powerup the PC after AC power failures.

Not all motherboards or bios settings gives power to PCI slots,
so this mode is not enabled on all the hardware.

4.16 linux driver introduced full hardware reset sequence
This is required since before that we had no NIC hardware
reset implemented and there were side effects of "not clean start".

But this full reset is incompatible with "dirty wake" WOL feature
it keeps the PHY link in a special mode forever. As a consequence,
driver sees no link and no traffic.

To fix this we forcibly change FW state to idle state before doing
the full reset. This makes FW to restore link state.

Fixes: c8c82eb net: aquantia: Introduce global AQC hardware reset sequence
Signed-off-by: Igor Russkikh <igor.russkikh at aquantia.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit cce96d1883dae4b79f44890e5118243d806da286)
Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
---
 .../aquantia/atlantic/hw_atl/hw_atl_utils.c      | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c
index d3b847ec7465..c58b2c227260 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c
@@ -48,6 +48,8 @@
 #define FORCE_FLASHLESS 0
 
 static int hw_atl_utils_ver_match(u32 ver_expected, u32 ver_actual);
+static int hw_atl_utils_mpi_set_state(struct aq_hw_s *self,
+				      enum hal_atl_utils_fw_state_e state);
 
 int hw_atl_utils_initfw(struct aq_hw_s *self, const struct aq_fw_ops **fw_ops)
 {
@@ -247,6 +249,20 @@ int hw_atl_utils_soft_reset(struct aq_hw_s *self)
 
 	self->rbl_enabled = (boot_exit_code != 0);
 
+	/* FW 1.x may bootup in an invalid POWER state (WOL feature).
+	 * We should work around this by forcing its state back to DEINIT
+	 */
+	if (!hw_atl_utils_ver_match(HW_ATL_FW_VER_1X,
+				    aq_hw_read_reg(self,
+						   HW_ATL_MPI_FW_VERSION))) {
+		int err = 0;
+
+		hw_atl_utils_mpi_set_state(self, MPI_DEINIT);
+		AQ_HW_WAIT_FOR((aq_hw_read_reg(self, HW_ATL_MPI_STATE_ADR) &
+			       HW_ATL_MPI_STATE_MSK) == MPI_DEINIT,
+			       10, 1000U);
+	}
+
 	if (self->rbl_enabled)
 		return hw_atl_utils_soft_reset_rbl(self);
 	else
-- 
2.17.0