Some em chips have a semaphore ("software flag") to synchronize access
to certain registers between OS and firmware (ME/AMT).
Make the logic to get the flag match the logic in freebsd. This includes
higher timeouts and waiting for a previous unlock to complete before
trying a lock again.
---
sys/dev/pci/if_em_hw.c | 22 +++++++++++++++++++---
sys/dev/pci/if_em_hw.h | 2 ++
2 files changed, 21 insertions(+), 3 deletions(-)
diff --git sys/dev/pci/if_em_hw.c sys/dev/pci/if_em_hw.c
index e5084252c29..5bba83cbcd4 100644
--- sys/dev/pci/if_em_hw.c
+++ sys/dev/pci/if_em_hw.c
@@ -9613,9 +9613,21 @@ em_get_software_flag(struct em_hw *hw)
if (IS_ICH8(hw->mac_type)) {
while (timeout) {
extcnf_ctrl = E1000_READ_REG(hw, EXTCNF_CTRL);
- extcnf_ctrl |= E1000_EXTCNF_CTRL_SWFLAG;
- E1000_WRITE_REG(hw, EXTCNF_CTRL, extcnf_ctrl);
+ if (!(extcnf_ctrl & E1000_EXTCNF_CTRL_SWFLAG))
+ break;
+ msec_delay_irq(1);
+ timeout--;
+ }
+ if (!timeout) {
+ printf("%s: SW has already locked the resource?\n",
+ __func__);
+ return -E1000_ERR_CONFIG;
+ }
+ timeout = SW_FLAG_TIMEOUT;
+ extcnf_ctrl |= E1000_EXTCNF_CTRL_SWFLAG;
+ E1000_WRITE_REG(hw, EXTCNF_CTRL, extcnf_ctrl);
+ while (timeout) {
extcnf_ctrl = E1000_READ_REG(hw, EXTCNF_CTRL);
if (extcnf_ctrl & E1000_EXTCNF_CTRL_SWFLAG)
break;
@@ -9624,7 +9636,11 @@ em_get_software_flag(struct em_hw *hw)
}
if (!timeout) {
- DEBUGOUT("FW or HW locks the resource too long.\n");
+ printf("Failed to acquire the semaphore, FW or HW "
+ "has it: FWSM=0x%8.8x EXTCNF_CTRL=0x%8.8x)\n",
+ E1000_READ_REG(hw, FWSM), extcnf_ctrl);
+ extcnf_ctrl &= ~E1000_EXTCNF_CTRL_SWFLAG;
+ E1000_WRITE_REG(hw, EXTCNF_CTRL, extcnf_ctrl);
return -E1000_ERR_CONFIG;
}
}
diff --git sys/dev/pci/if_em_hw.h sys/dev/pci/if_em_hw.h
index 5e415e60a34..71dc91e5582 100644
--- sys/dev/pci/if_em_hw.h
+++ sys/dev/pci/if_em_hw.h
@@ -2755,6 +2755,8 @@ struct em_host_command_info {
#define AUTO_READ_DONE_TIMEOUT 10
/* Number of milliseconds we wait for PHY configuration done after MAC reset */
#define PHY_CFG_TIMEOUT 100
+/* SW Semaphore flag timeout in ms */
+#define SW_FLAG_TIMEOUT 1000
#define E1000_TX_BUFFER_SIZE ((uint32_t)1514)
--
2.13.0
