drivers: usb: xhci-fsl: Change burst beat and outstanding pipelined transfers requests

This is required for better performance, and performs below tuning:
1. Enable burst length set, and define it as 4/8/16.
2. Set burst request limit to 16 requests.

Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
diff --git a/drivers/usb/host/xhci-fsl.c b/drivers/usb/host/xhci-fsl.c
index bda5b5f..2529d0e 100644
--- a/drivers/usb/host/xhci-fsl.c
+++ b/drivers/usb/host/xhci-fsl.c
@@ -58,6 +58,13 @@
 	}
 }
 
+static void fsl_xhci_set_beat_burst_length(struct dwc3 *dwc3_reg)
+{
+	clrsetbits_le32(&dwc3_reg->g_sbuscfg0, USB3_ENABLE_BEAT_BURST_MASK,
+			USB3_ENABLE_BEAT_BURST);
+	setbits_le32(&dwc3_reg->g_sbuscfg1, USB3_SET_BEAT_BURST_LIMIT);
+}
+
 static int fsl_xhci_core_init(struct fsl_xhci *fsl_xhci)
 {
 	int ret = 0;
@@ -74,6 +81,9 @@
 	/* Set GFLADJ_30MHZ as 20h as per XHCI spec default value */
 	dwc3_set_fladj(fsl_xhci->dwc3_reg, GFLADJ_30MHZ_DEFAULT);
 
+	/* Change beat burst and outstanding pipelined transfers requests */
+	fsl_xhci_set_beat_burst_length(fsl_xhci->dwc3_reg);
+
 	return ret;
 }