ice: delay less

Shorten the delay for SQ responses, but increase the number of loops.
Max delay time is unchanged, but some operations complete much more
quickly.

In the process, add a new define to make the delay count and delay time
more explicit. Add comments to make things more explicit.

This fixes a problem with VF resets failing on with many VFs.
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ice/ice_controlq.c

@@ -948,7 +948,7 @@ ice_sq_send_cmd(struct ice_hw *hw, struct ice_ctl_q_info *cq,
 		if (ice_sq_done(hw, cq))
 			break;
 
-		mdelay(1);
+		udelay(ICE_CTL_Q_SQ_CMD_USEC);
 		total_delay++;
 	} while (total_delay < cq->sq_cmd_timeout);
 

drivers/net/ethernet/intel/ice/ice_controlq.h

@@ -31,8 +31,9 @@ enum ice_ctl_q {
 	ICE_CTL_Q_MAILBOX,
 };
 
-/* Control Queue default settings */
-#define ICE_CTL_Q_SQ_CMD_TIMEOUT	250  /* msecs */
+/* Control Queue timeout settings - max delay 250ms */
+#define ICE_CTL_Q_SQ_CMD_TIMEOUT	2500  /* Count 2500 times */
+#define ICE_CTL_Q_SQ_CMD_USEC		100   /* Check every 100usec */
 
 struct ice_ctl_q_ring {
 	void *dma_head;			/* Virtual address to DMA head */