1 files changed, 65 insertions, 0 deletions
diff --git a/arch/powerpc/boot/mpc52xx-psc.c b/arch/powerpc/boot/mpc52xx-psc.c
new file mode 100644
index 000000000..c2c08633e
--- /dev/null
+++ b/arch/powerpc/boot/mpc52xx-psc.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MPC5200 PSC serial console support.
+ *
+ * Author: Grant Likely <grant.likely@secretlab.ca>
+ *
+ * Copyright (c) 2007 Secret Lab Technologies Ltd.
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ *
+ * It is assumed that the firmware (or the platform file) has already set
+ * up the port.
+ */
+
+#include "types.h"
+#include "io.h"
+#include "ops.h"
+
+/* Programmable Serial Controller (PSC) status register bits */
+#define MPC52xx_PSC_SR		0x04
+#define MPC52xx_PSC_SR_RXRDY		0x0100
+#define MPC52xx_PSC_SR_RXFULL		0x0200
+#define MPC52xx_PSC_SR_TXRDY		0x0400
+#define MPC52xx_PSC_SR_TXEMP		0x0800
+
+#define MPC52xx_PSC_BUFFER	0x0C
+
+static void *psc;
+
+static int psc_open(void)
+{
+	/* Assume the firmware has already configured the PSC into
+	 * uart mode */
+	return 0;
+}
+
+static void psc_putc(unsigned char c)
+{
+	while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_TXRDY)) ;
+	out_8(psc + MPC52xx_PSC_BUFFER, c);
+}
+
+static unsigned char psc_tstc(void)
+{
+	return (in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY) != 0;
+}
+
+static unsigned char psc_getc(void)
+{
+	while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY)) ;
+	return in_8(psc + MPC52xx_PSC_BUFFER);
+}
+
+int mpc5200_psc_console_init(void *devp, struct serial_console_data *scdp)
+{
+	/* Get the base address of the psc registers */
+	if (dt_get_virtual_reg(devp, &psc, 1) < 1)
+		return -1;
+
+	scdp->open = psc_open;
+	scdp->putc = psc_putc;
+	scdp->getc = psc_getc;
+	scdp->tstc = psc_tstc;
+
+	return 0;
+}