ice: Add support for dynamic interrupt moderation

Currently there is no support for dynamic interrupt moderation. This
patch adds some initial code to support this. The following changes
were made:

1. Currently we are using multiple members to store the interrupt
   granularity (itr_gran_25/50/100/200). This is not necessary because
   we can query the device to determine what the interrupt granularity
   should be set to, done by a new function ice_get_itr_intrl_gran.

2. Added intrl to ice_q_vector structure to support interrupt rate
   limiting.

3. Added the function ice_intrl_usecs_to_reg for converting to a value
   in usecs that the device understands.

4. Added call to write to the GLINT_RATE register. Disable intrl by
   default for now.

5. Changed rx/tx_itr_setting to itr_setting because having both seems
   redundant because a ring is either Tx or Rx.

6. Initialize itr_setting for both Tx/Rx rings in ice_vsi_alloc_rings()

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 19 insertions, 9 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_type.h b/drivers/net/ethernet/intel/ice/ice_type.h
index 87930f68d3fb..f5c8de0ed0eb 100644
--- a/drivers/net/ethernet/intel/ice/ice_type.h
+++ b/drivers/net/ethernet/intel/ice/ice_type.h
@@ -333,16 +333,26 @@ struct ice_hw {
 	u32 fw_build;		/* firmware build number */
 
 	struct ice_fw_log_cfg fw_log;
-	/* minimum allowed value for different speeds */
-#define ICE_ITR_GRAN_MIN_200	1
-#define ICE_ITR_GRAN_MIN_100	1
-#define ICE_ITR_GRAN_MIN_50	2
-#define ICE_ITR_GRAN_MIN_25	4
+
+/* Device max aggregate bandwidths corresponding to the GL_PWR_MODE_CTL
+ * register. Used for determining the itr/intrl granularity during
+ * initialization.
+ */
+#define ICE_MAX_AGG_BW_200G	0x0
+#define ICE_MAX_AGG_BW_100G	0X1
+#define ICE_MAX_AGG_BW_50G	0x2
+#define ICE_MAX_AGG_BW_25G	0x3
+	/* ITR granularity for different speeds */
+#define ICE_ITR_GRAN_ABOVE_25	2
+#define ICE_ITR_GRAN_MAX_25	4
 	/* ITR granularity in 1 us */
-	u8 itr_gran_200;
-	u8 itr_gran_100;
-	u8 itr_gran_50;
-	u8 itr_gran_25;
+	u8 itr_gran;
+	/* INTRL granularity for different speeds */
+#define ICE_INTRL_GRAN_ABOVE_25	4
+#define ICE_INTRL_GRAN_MAX_25	8
+	/* INTRL granularity in 1 us */
+	u8 intrl_gran;
+
 	u8 ucast_shared;	/* true if VSIs can share unicast addr */
 
 };