powerpc/mpc5121: move PSC FIFO memory init to platform code

Since PSC could also be used in other modes than UART mode
we move PSC FIFO memory initialization from serial driver to
common platform code. The initialized FIFO memory slices may
not overlap, so the most easy way would be to configure them
all at once at init time for all PSC devices. This is now done
by this patch.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 78 insertions, 0 deletions

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();
 }