ixgbe: Add I2C bus mux support

Take control of an I2C mux that selects which SFP is attached to
the I2C bus. The control of the mux is captured in the taking and
releasing of the related semaphore. Because only port 1 can control
the mux, port 1 always leaves the mux set to select port 0.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 61 insertions, 36 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
index 4e758435ece8..ccf853f7b73e 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
@@ -567,19 +567,25 @@ static s32 ixgbe_poll_flash_update_done_X540(struct ixgbe_hw *hw)
  **/
 s32 ixgbe_acquire_swfw_sync_X540(struct ixgbe_hw *hw, u32 mask)
 {
-	u32 swfw_sync;
-	u32 swmask = mask;
-	u32 fwmask = mask << 5;
-	u32 hwmask = 0;
+	u32 swmask = mask & IXGBE_GSSR_NVM_PHY_MASK;
+	u32 swi2c_mask = mask & IXGBE_GSSR_I2C_MASK;
+	u32 fwmask = swmask << 5;
 	u32 timeout = 200;
+	u32 hwmask = 0;
+	u32 swfw_sync;
 	u32 i;
 
-	if (swmask == IXGBE_GSSR_EEP_SM)
+	if (swmask & IXGBE_GSSR_EEP_SM)
 		hwmask = IXGBE_GSSR_FLASH_SM;
 
+	/* SW only mask does not have FW bit pair */
+	if (mask & IXGBE_GSSR_SW_MNG_SM)
+		swmask |= IXGBE_GSSR_SW_MNG_SM;
+
+	swmask |= swi2c_mask;
+	fwmask |= swi2c_mask << 2;
 	for (i = 0; i < timeout; i++) {
-		/*
-		 * SW NVM semaphore bit is used for access to all
+		/* SW NVM semaphore bit is used for access to all
 		 * SW_FW_SYNC bits (not just NVM)
 		 */
 		if (ixgbe_get_swfw_sync_semaphore(hw))
@@ -590,39 +596,56 @@ s32 ixgbe_acquire_swfw_sync_X540(struct ixgbe_hw *hw, u32 mask)
 			swfw_sync |= swmask;
 			IXGBE_WRITE_REG(hw, IXGBE_SWFW_SYNC(hw), swfw_sync);
 			ixgbe_release_swfw_sync_semaphore(hw);
-			break;
-		} else {
-			/*
-			 * Firmware currently using resource (fwmask),
-			 * hardware currently using resource (hwmask),
-			 * or other software thread currently using
-			 * resource (swmask)
-			 */
-			ixgbe_release_swfw_sync_semaphore(hw);
-			usleep_range(5000, 10000);
+			usleep_range(5000, 6000);
+			return 0;
 		}
+		/* Firmware currently using resource (fwmask), hardware
+		 * currently using resource (hwmask), or other software
+		 * thread currently using resource (swmask)
+		 */
+		ixgbe_release_swfw_sync_semaphore(hw);
+		usleep_range(5000, 10000);
 	}
 
-	/*
-	 * If the resource is not released by the FW/HW the SW can assume that
-	 * the FW/HW malfunctions. In that case the SW should sets the
-	 * SW bit(s) of the requested resource(s) while ignoring the
-	 * corresponding FW/HW bits in the SW_FW_SYNC register.
-	 */
-	if (i >= timeout) {
-		swfw_sync = IXGBE_READ_REG(hw, IXGBE_SWFW_SYNC(hw));
-		if (swfw_sync & (fwmask | hwmask)) {
-			if (ixgbe_get_swfw_sync_semaphore(hw))
-				return IXGBE_ERR_SWFW_SYNC;
+	/* Failed to get SW only semaphore */
+	if (swmask == IXGBE_GSSR_SW_MNG_SM) {
+		hw_dbg(hw, "Failed to get SW only semaphore\n");
+		return IXGBE_ERR_SWFW_SYNC;
+	}
 
-			swfw_sync |= swmask;
-			IXGBE_WRITE_REG(hw, IXGBE_SWFW_SYNC(hw), swfw_sync);
-			ixgbe_release_swfw_sync_semaphore(hw);
-		}
+	/* If the resource is not released by the FW/HW the SW can assume that
+	 * the FW/HW malfunctions. In that case the SW should set the SW bit(s)
+	 * of the requested resource(s) while ignoring the corresponding FW/HW
+	 * bits in the SW_FW_SYNC register.
+	 */
+	if (ixgbe_get_swfw_sync_semaphore(hw))
+		return IXGBE_ERR_SWFW_SYNC;
+	swfw_sync = IXGBE_READ_REG(hw, IXGBE_SWFW_SYNC(hw));
+	if (swfw_sync & (fwmask | hwmask)) {
+		swfw_sync |= swmask;
+		IXGBE_WRITE_REG(hw, IXGBE_SWFW_SYNC(hw), swfw_sync);
+		ixgbe_release_swfw_sync_semaphore(hw);
+		usleep_range(5000, 6000);
+		return 0;
+	}
+	/* If the resource is not released by other SW the SW can assume that
+	 * the other SW malfunctions. In that case the SW should clear all SW
+	 * flags that it does not own and then repeat the whole process once
+	 * again.
+	 */
+	if (swfw_sync & swmask) {
+		u32 rmask = IXGBE_GSSR_EEP_SM | IXGBE_GSSR_PHY0_SM |
+			    IXGBE_GSSR_PHY1_SM | IXGBE_GSSR_MAC_CSR_SM;
+
+		if (swi2c_mask)
+			rmask |= IXGBE_GSSR_I2C_MASK;
+		ixgbe_release_swfw_sync_X540(hw, rmask);
+		ixgbe_release_swfw_sync_semaphore(hw);
+		return IXGBE_ERR_SWFW_SYNC;
 	}
+	ixgbe_release_swfw_sync_semaphore(hw);
 
-	usleep_range(5000, 10000);
-	return 0;
+	return IXGBE_ERR_SWFW_SYNC;
 }
 
 /**
@@ -635,9 +658,11 @@ s32 ixgbe_acquire_swfw_sync_X540(struct ixgbe_hw *hw, u32 mask)
  **/
 void ixgbe_release_swfw_sync_X540(struct ixgbe_hw *hw, u32 mask)
 {
+	u32 swmask = mask & (IXGBE_GSSR_NVM_PHY_MASK | IXGBE_GSSR_SW_MNG_SM);
 	u32 swfw_sync;
-	u32 swmask = mask;
 
+	if (mask & IXGBE_GSSR_I2C_MASK)
+		swmask |= mask & IXGBE_GSSR_I2C_MASK;
 	ixgbe_get_swfw_sync_semaphore(hw);
 
 	swfw_sync = IXGBE_READ_REG(hw, IXGBE_SWFW_SYNC(hw));
@@ -645,7 +670,7 @@ void ixgbe_release_swfw_sync_X540(struct ixgbe_hw *hw, u32 mask)
 	IXGBE_WRITE_REG(hw, IXGBE_SWFW_SYNC(hw), swfw_sync);
 
 	ixgbe_release_swfw_sync_semaphore(hw);
-	usleep_range(5000, 10000);
+	usleep_range(5000, 6000);
 }
 
 /**