ice: add support for sideband messages

In order to support certain device features, including enabling the PTP
hardware clock, the ice driver needs to control some registers on the
device PHY.

These registers are accessed by sending sideband messages. For some
hardware, these messages must be sent over the device admin queue, while
other hardware has a dedicated control queue for the sideband messages.

Add the neighbor device message structure for sending a message to the
neighboring device. Where supported, initialize the sideband control
queue and handle cleanup.

Add a wrapper function for sending sideband control queue messages that
read or write a neighboring device register.

Because some devices send sideband messages over the AdminQ, also
increase the length of the admin queue to allow more messages to be
queued up. This is important because the sideband messages add
additional pressure on the AQ usage.

This support will be used in following patches to enable support for
CONFIG_1588_PTP_CLOCK.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.c b/drivers/net/ethernet/intel/ice/ice_controlq.c
index 87b33bdd4960..03bdb125be36 100644
--- a/drivers/net/ethernet/intel/ice/ice_controlq.c
+++ b/drivers/net/ethernet/intel/ice/ice_controlq.c
@@ -52,6 +52,19 @@ static void ice_mailbox_init_regs(struct ice_hw *hw)
 }
 
 /**
+ * ice_sb_init_regs - Initialize Sideband registers
+ * @hw: pointer to the hardware structure
+ *
+ * This assumes the alloc_sq and alloc_rq functions have already been called
+ */
+static void ice_sb_init_regs(struct ice_hw *hw)
+{
+	struct ice_ctl_q_info *cq = &hw->sbq;
+
+	ICE_CQ_INIT_REGS(cq, PF_SB);
+}
+
+/**
  * ice_check_sq_alive
  * @hw: pointer to the HW struct
  * @cq: pointer to the specific Control queue
@@ -609,6 +622,10 @@ static enum ice_status ice_init_ctrlq(struct ice_hw *hw, enum ice_ctl_q q_type)
 		ice_adminq_init_regs(hw);
 		cq = &hw->adminq;
 		break;
+	case ICE_CTL_Q_SB:
+		ice_sb_init_regs(hw);
+		cq = &hw->sbq;
+		break;
 	case ICE_CTL_Q_MAILBOX:
 		ice_mailbox_init_regs(hw);
 		cq = &hw->mailboxq;
@@ -646,6 +663,32 @@ init_ctrlq_free_sq:
 }
 
 /**
+ * ice_is_sbq_supported - is the sideband queue supported
+ * @hw: pointer to the hardware structure
+ *
+ * Returns true if the sideband control queue interface is
+ * supported for the device, false otherwise
+ */
+bool ice_is_sbq_supported(struct ice_hw *hw)
+{
+	/* The device sideband queue is only supported on devices with the
+	 * generic MAC type.
+	 */
+	return hw->mac_type == ICE_MAC_GENERIC;
+}
+
+/**
+ * ice_get_sbq - returns the right control queue to use for sideband
+ * @hw: pointer to the hardware structure
+ */
+struct ice_ctl_q_info *ice_get_sbq(struct ice_hw *hw)
+{
+	if (ice_is_sbq_supported(hw))
+		return &hw->sbq;
+	return &hw->adminq;
+}
+
+/**
  * ice_shutdown_ctrlq - shutdown routine for any control queue
  * @hw: pointer to the hardware structure
  * @q_type: specific Control queue type
@@ -662,6 +705,9 @@ static void ice_shutdown_ctrlq(struct ice_hw *hw, enum ice_ctl_q q_type)
 		if (ice_check_sq_alive(hw, cq))
 			ice_aq_q_shutdown(hw, true);
 		break;
+	case ICE_CTL_Q_SB:
+		cq = &hw->sbq;
+		break;
 	case ICE_CTL_Q_MAILBOX:
 		cq = &hw->mailboxq;
 		break;
@@ -685,6 +731,9 @@ void ice_shutdown_all_ctrlq(struct ice_hw *hw)
 {
 	/* Shutdown FW admin queue */
 	ice_shutdown_ctrlq(hw, ICE_CTL_Q_ADMIN);
+	/* Shutdown PHY Sideband */
+	if (ice_is_sbq_supported(hw))
+		ice_shutdown_ctrlq(hw, ICE_CTL_Q_SB);
 	/* Shutdown PF-VF Mailbox */
 	ice_shutdown_ctrlq(hw, ICE_CTL_Q_MAILBOX);
 }
@@ -724,6 +773,15 @@ enum ice_status ice_init_all_ctrlq(struct ice_hw *hw)
 
 	if (status)
 		return status;
+	/* sideband control queue (SBQ) interface is not supported on some
+	 * devices. Initialize if supported, else fallback to the admin queue
+	 * interface
+	 */
+	if (ice_is_sbq_supported(hw)) {
+		status = ice_init_ctrlq(hw, ICE_CTL_Q_SB);
+		if (status)
+			return status;
+	}
 	/* Init Mailbox queue */
 	return ice_init_ctrlq(hw, ICE_CTL_Q_MAILBOX);
 }
@@ -759,6 +817,8 @@ static void ice_init_ctrlq_locks(struct ice_ctl_q_info *cq)
 enum ice_status ice_create_all_ctrlq(struct ice_hw *hw)
 {
 	ice_init_ctrlq_locks(&hw->adminq);
+	if (ice_is_sbq_supported(hw))
+		ice_init_ctrlq_locks(&hw->sbq);
 	ice_init_ctrlq_locks(&hw->mailboxq);
 
 	return ice_init_all_ctrlq(hw);
@@ -791,6 +851,8 @@ void ice_destroy_all_ctrlq(struct ice_hw *hw)
 	ice_shutdown_all_ctrlq(hw);
 
 	ice_destroy_ctrlq_locks(&hw->adminq);
+	if (ice_is_sbq_supported(hw))
+		ice_destroy_ctrlq_locks(&hw->sbq);
 	ice_destroy_ctrlq_locks(&hw->mailboxq);
 }