2 files changed, 79 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/mpc52xx_psc.h b/arch/powerpc/include/asm/mpc52xx_psc.h
index 42561f4f032d..ecc4fc69ac13 100644
--- a/arch/powerpc/include/asm/mpc52xx_psc.h
+++ b/arch/powerpc/include/asm/mpc52xx_psc.h
@@ -248,6 +248,7 @@ struct mpc52xx_psc_fifo {
 	u16		tflwfptr;	/* PSC + 0x9e */
 };
 
+#define MPC512x_PSC_FIFO_EOF		0x100
 #define MPC512x_PSC_FIFO_RESET_SLICE	0x80
 #define MPC512x_PSC_FIFO_ENABLE_SLICE	0x01
 #define MPC512x_PSC_FIFO_ENABLE_DMA	0x04
diff --git a/arch/powerpc/platforms/512x/mpc512x_shared.c b/arch/powerpc/platforms/512x/mpc512x_shared.c
index b7f518a60f03..707e572b7c40 100644
--- a/arch/powerpc/platforms/512x/mpc512x_shared.c
+++ b/arch/powerpc/platforms/512x/mpc512x_shared.c
@@ -22,6 +22,7 @@
 #include <asm/prom.h>
 #include <asm/time.h>
 #include <asm/mpc5121.h>
+#include <asm/mpc52xx_psc.h>
 
 #include "mpc512x.h"
 
@@ -95,9 +96,86 @@ void __init mpc512x_declare_of_platform_devices(void)
 	}
 }
 
+#define DEFAULT_FIFO_SIZE 16
+
+static unsigned int __init get_fifo_size(struct device_node *np,
+					 char *prop_name)
+{
+	const unsigned int *fp;
+
+	fp = of_get_property(np, prop_name, NULL);
+	if (fp)
+		return *fp;
+
+	pr_warning("no %s property in %s node, defaulting to %d\n",
+		   prop_name, np->full_name, DEFAULT_FIFO_SIZE);
+
+	return DEFAULT_FIFO_SIZE;
+}
+
+#define FIFOC(_base) ((struct mpc512x_psc_fifo __iomem *) \
+		    ((u32)(_base) + sizeof(struct mpc52xx_psc)))
+
+/* Init PSC FIFO space for TX and RX slices */
+void __init mpc512x_psc_fifo_init(void)
+{
+	struct device_node *np;
+	void __iomem *psc;
+	unsigned int tx_fifo_size;
+	unsigned int rx_fifo_size;
+	int fifobase = 0; /* current fifo address in 32 bit words */
+
+	for_each_compatible_node(np, NULL, "fsl,mpc5121-psc") {
+		tx_fifo_size = get_fifo_size(np, "fsl,tx-fifo-size");
+		rx_fifo_size = get_fifo_size(np, "fsl,rx-fifo-size");
+
+		/* size in register is in 4 byte units */
+		tx_fifo_size /= 4;
+		rx_fifo_size /= 4;
+		if (!tx_fifo_size)
+			tx_fifo_size = 1;
+		if (!rx_fifo_size)
+			rx_fifo_size = 1;
+
+		psc = of_iomap(np, 0);
+		if (!psc) {
+			pr_err("%s: Can't map %s device\n",
+				__func__, np->full_name);
+			continue;
+		}
+
+		/* FIFO space is 4KiB, check if requested size is available */
+		if ((fifobase + tx_fifo_size + rx_fifo_size) > 0x1000) {
+			pr_err("%s: no fifo space available for %s\n",
+				__func__, np->full_name);
+			iounmap(psc);
+			/*
+			 * chances are that another device requests less
+			 * fifo space, so we continue.
+			 */
+			continue;
+		}
+
+		/* set tx and rx fifo size registers */
+		out_be32(&FIFOC(psc)->txsz, (fifobase << 16) | tx_fifo_size);
+		fifobase += tx_fifo_size;
+		out_be32(&FIFOC(psc)->rxsz, (fifobase << 16) | rx_fifo_size);
+		fifobase += rx_fifo_size;
+
+		/* reset and enable the slices */
+		out_be32(&FIFOC(psc)->txcmd, 0x80);
+		out_be32(&FIFOC(psc)->txcmd, 0x01);
+		out_be32(&FIFOC(psc)->rxcmd, 0x80);
+		out_be32(&FIFOC(psc)->rxcmd, 0x01);
+
+		iounmap(psc);
+	}
+}
+
 void __init mpc512x_init(void)
 {
 	mpc512x_declare_of_platform_devices();
 	mpc5121_clk_init();
 	mpc512x_restart_init();
+	mpc512x_psc_fifo_init();
 }