e1000: releasing semaphore once no longer needed

Once the hwsw semaphore is acquired, it must be released when access to the
hw is completed. Without this subsequent calls to acquire will timeout
obtaining the semaphore.

Cc: Marcel Ziswiler <marcel@ziswiler.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Aneesh Bansal <aneesh.bansal@freescale.com>
Cc: Naveen Burmi <NaveenBurmi@freescale.com>
Cc: Po Liu <po.liu@freescale.com>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Alison Wang <alison.wang@freescale.com>
Cc: Reinhard Arlt <reinhard.arlt@esd-electronics.com>
Cc: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Cc: York Sun <yorksun@freescale.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>

drivers/net/e1000.c

@@ -126,6 +126,7 @@ static int e1000_detect_gig_phy(struct e1000_hw *hw);
 static void e1000_set_media_type(struct e1000_hw *hw);
 
 static int32_t e1000_swfw_sync_acquire(struct e1000_hw *hw, uint16_t mask);
+static void e1000_swfw_sync_release(struct e1000_hw *hw, uint16_t mask);
 static int32_t e1000_check_phy_reset_block(struct e1000_hw *hw);
 
 #ifndef CONFIG_E1000_NO_NVM
@@ -729,7 +730,10 @@ void e1000_release_eeprom(struct e1000_hw *hw)
 		eecd &= ~E1000_EECD_REQ;
 		E1000_WRITE_REG(hw, EECD, eecd);
 	}
+
+	e1000_swfw_sync_release(hw, E1000_SWFW_EEP_SM);
 }
+
 /******************************************************************************
  * Reads a 16 bit word from the EEPROM.
  *
@@ -1102,6 +1106,7 @@ e1000_get_hw_eeprom_semaphore(struct e1000_hw *hw)
 	return E1000_SUCCESS;
 }
 
+/* Take ownership of the PHY */
 static int32_t
 e1000_swfw_sync_acquire(struct e1000_hw *hw, uint16_t mask)
 {
@@ -1141,6 +1146,21 @@ e1000_swfw_sync_acquire(struct e1000_hw *hw, uint16_t mask)
 	return E1000_SUCCESS;
 }
 
+static void e1000_swfw_sync_release(struct e1000_hw *hw, uint16_t mask)
+{
+	uint32_t swfw_sync = 0;
+
+	DEBUGFUNC();
+	while (e1000_get_hw_eeprom_semaphore(hw))
+		; /* Empty */
+
+	swfw_sync = E1000_READ_REG(hw, SW_FW_SYNC);
+	swfw_sync &= ~mask;
+	E1000_WRITE_REG(hw, SW_FW_SYNC, swfw_sync);
+
+	e1000_put_hw_eeprom_semaphore(hw);
+}
+
 static bool e1000_is_second_port(struct e1000_hw *hw)
 {
 	switch (hw->mac_type) {
@@ -4462,6 +4482,8 @@ e1000_phy_hw_reset(struct e1000_hw *hw)
 		E1000_WRITE_REG(hw, LEDCTL, led_ctrl);
 	}
 
+	e1000_swfw_sync_release(hw, swfw);
+
 	/* Wait for FW to finish PHY configuration. */
 	ret_val = e1000_get_phy_cfg_done(hw);
 	if (ret_val != E1000_SUCCESS)