serial: Make ucc_uart work in HW UART mode

In HW UART mode the TxBD[READY] is not cleared by H/W (RISC engine) when
the user send characters to Tx buffer of QE UART.  So, these characters
stay on the QE forever, never go to UART line.

Signed-off-by: Dave Liu <daveliu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

drivers/serial/ucc_uart.c

@@ -681,22 +681,27 @@ static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
 	out_be16(&uccup->rccm, 0xc0ff);
 
 	/* Configure the GUMR registers for UART */
-	if (soft_uart)
+	if (soft_uart) {
 		/* Soft-UART requires a 1X multiplier for TX */
 		clrsetbits_be32(&uccp->gumr_l,
 			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
 			UCC_SLOW_GUMR_L_RDCR_MASK,
 			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
 			UCC_SLOW_GUMR_L_RDCR_16);
-	else
+
+		clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
+			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
+	} else {
 		clrsetbits_be32(&uccp->gumr_l,
 			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
 			UCC_SLOW_GUMR_L_RDCR_MASK,
 			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
 			UCC_SLOW_GUMR_L_RDCR_16);
 
-	clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
-		UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
+		clrsetbits_be32(&uccp->gumr_h,
+			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
+			UCC_SLOW_GUMR_H_RFW);
+	}
 
 #ifdef LOOPBACK
 	clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
@@ -706,7 +711,7 @@ static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
 		UCC_SLOW_GUMR_H_CDS);
 #endif
 
-	/* Enable rx interrupts  and clear all pending events.  */
+	/* Disable rx interrupts  and clear all pending events.  */
 	out_be16(&uccp->uccm, 0);
 	out_be16(&uccp->ucce, 0xffff);
 	out_be16(&uccp->udsr, 0x7e7e);
@@ -765,6 +770,10 @@ static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
 		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
 			QE_CR_PROTOCOL_UNSPECIFIED, 0);
+	} else {
+		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
+		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
+			QE_CR_PROTOCOL_UART, 0);
 	}
 }