diff mbox series

[v2,15/42] net/e1000/base: modify HW level time sync mechanisms

Message ID 20200624075337.6768-16-guinanx.sun@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Qi Zhang
Headers show
Series update e1000 base code | expand

Checks

Context Check Description
ci/Intel-compilation success Compilation OK
ci/checkpatch success coding style OK

Commit Message

Guinan Sun June 24, 2020, 7:53 a.m. UTC
Add additinal configuration space access to allow HW
level time sync mechanism.

Signed-off-by: Efimov Evgeny <evgeny.efimov@intel.com>
Signed-off-by: Guinan Sun <guinanx.sun@intel.com>
---
 drivers/net/e1000/base/e1000_ich8lan.c | 18 ++++++++++++++++++
 drivers/net/e1000/base/e1000_ich8lan.h |  1 +
 2 files changed, 19 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/e1000/base/e1000_ich8lan.c b/drivers/net/e1000/base/e1000_ich8lan.c
index 133cef4cd..4790196f2 100644
--- a/drivers/net/e1000/base/e1000_ich8lan.c
+++ b/drivers/net/e1000/base/e1000_ich8lan.c
@@ -4894,6 +4894,7 @@  STATIC s32 e1000_reset_hw_ich8lan(struct e1000_hw *hw)
 	u16 kum_cfg;
 	u32 ctrl, reg;
 	s32 ret_val;
+	u16 pci_cfg;
 
 	DEBUGFUNC("e1000_reset_hw_ich8lan");
 
@@ -4954,11 +4955,28 @@  STATIC s32 e1000_reset_hw_ich8lan(struct e1000_hw *hw)
 			e1000_gate_hw_phy_config_ich8lan(hw, true);
 	}
 	ret_val = e1000_acquire_swflag_ich8lan(hw);
+
+	/* Read from EXTCNF_CTRL in e1000_acquire_swflag_ich8lan function
+	 * may occur during global reset and cause system hang.
+	 * Configuration space access creates the needed delay.
+	 * Write to E1000_STRAP RO register E1000_PCI_VENDOR_ID_REGISTER value
+	 * insures configuration space read is done before global reset.
+	 */
+	e1000_read_pci_cfg(hw, E1000_PCI_VENDOR_ID_REGISTER, &pci_cfg);
+	E1000_WRITE_REG(hw, E1000_STRAP, pci_cfg);
 	DEBUGOUT("Issuing a global reset to ich8lan\n");
 	E1000_WRITE_REG(hw, E1000_CTRL, (ctrl | E1000_CTRL_RST));
 	/* cannot issue a flush here because it hangs the hardware */
 	msec_delay(20);
 
+	/* Configuration space access improve HW level time sync mechanism.
+	 * Write to E1000_STRAP RO register E1000_PCI_VENDOR_ID_REGISTER
+	 * value to insure configuration space read is done
+	 * before any access to mac register.
+	 */
+	e1000_read_pci_cfg(hw, E1000_PCI_VENDOR_ID_REGISTER, &pci_cfg);
+	E1000_WRITE_REG(hw, E1000_STRAP, pci_cfg);
+
 	/* Set Phy Config Counter to 50msec */
 	if (hw->mac.type == e1000_pch2lan) {
 		reg = E1000_READ_REG(hw, E1000_FEXTNVM3);
diff --git a/drivers/net/e1000/base/e1000_ich8lan.h b/drivers/net/e1000/base/e1000_ich8lan.h
index 9c21396c3..bfee467b3 100644
--- a/drivers/net/e1000/base/e1000_ich8lan.h
+++ b/drivers/net/e1000/base/e1000_ich8lan.h
@@ -287,6 +287,7 @@ 
 /* Receive Address Initial CRC Calculation */
 #define E1000_PCH_RAICC(_n)	(0x05F50 + ((_n) * 4))
 
+#define E1000_PCI_VENDOR_ID_REGISTER	0x00
 #if defined(QV_RELEASE) || !defined(NO_PCH_LPT_B0_SUPPORT)
 #define E1000_PCI_REVISION_ID_REG	0x08
 #endif /* defined(QV_RELEASE) || !defined(NO_PCH_LPT_B0_SUPPORT) */