[POWERPC] Add device tree utility functions to zImage

This patch adds a library of useful device tree manipulation functions
to the zImage library, for use by platform code.  These functions are
based on the hooks already in dt_ops, so they're not dependent on a
particular device tree implementation.  This patch also slightly
streamlines the code in main.c using these new functions.

This is a consolidation of my work in this area with Scott Wood's
patches to a very similar end.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

4 files changed, 136 insertions, 17 deletions

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index de80e47d1171..fac6ed0c5bcd 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -42,7 +42,7 @@ $(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) \
 
 src-wlib := string.S crt0.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
                 ns16550.c serial.c simple_alloc.c div64.S util.S \
-                gunzip_util.c $(zlib)
+                gunzip_util.c $(zlib) devtree.c
 src-plat := of.c
 src-boot := $(src-wlib) $(src-plat) empty.c
 
diff --git a/arch/powerpc/boot/devtree.c b/arch/powerpc/boot/devtree.c
new file mode 100644
index 000000000000..708cadebeb46
--- /dev/null
+++ b/arch/powerpc/boot/devtree.c
@@ -0,0 +1,111 @@
+/*
+ * devtree.c - convenience functions for device tree manipulation
+ * Copyright 2007 David Gibson, IBM Corporation.
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ *
+ * Authors: David Gibson <david@gibson.dropbear.id.au>
+ *          Scott Wood <scottwood@freescale.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "string.h"
+#include "stdio.h"
+#include "ops.h"
+
+void dt_fixup_memory(u64 start, u64 size)
+{
+        void *root, *memory;
+        int naddr, nsize, i;
+        u32 memreg[4];
+
+        root = finddevice("/");
+        if (getprop(root, "#address-cells", &naddr, sizeof(naddr)) < 0)
+                naddr = 2;
+        if (naddr < 1 || naddr > 2)
+                fatal("Can't cope with #address-cells == %d in /\n\r", naddr);
+
+        if (getprop(root, "#size-cells", &nsize, sizeof(nsize)) < 0)
+                nsize = 1;
+        if (nsize < 1 || nsize > 2)
+                fatal("Can't cope with #size-cells == %d in /\n\r", nsize);
+
+        i = 0;
+        if (naddr == 2)
+                memreg[i++] = start >> 32;
+        memreg[i++] = start & 0xffffffff;
+        if (nsize == 2)
+                memreg[i++] = size >> 32;
+        memreg[i++] = size & 0xffffffff;
+
+        memory = finddevice("/memory");
+        if (! memory) {
+                memory = create_node(NULL, "memory");
+                setprop_str(memory, "device_type", "memory");
+        }
+
+        printf("Memory <- <0x%x", memreg[0]);
+        for (i = 1; i < (naddr + nsize); i++)
+                printf(" 0x%x", memreg[i]);
+        printf("> (%ldMB)\n\r", (unsigned long)(size >> 20));
+
+        setprop(memory, "reg", memreg, (naddr + nsize)*sizeof(u32));
+}
+
+#define MHZ(x)  ((x + 500000) / 1000000)
+
+void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
+{
+        void *devp = NULL;
+
+        printf("CPU clock-frequency <- 0x%x (%dMHz)\n\r", cpu, MHZ(cpu));
+        printf("CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
+        if (bus > 0)
+                printf("CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));
+
+        while ((devp = find_node_by_devtype(devp, "cpu"))) {
+                setprop_val(devp, "clock-frequency", cpu);
+                setprop_val(devp, "timebase-frequency", tb);
+                if (bus > 0)
+                        setprop_val(devp, "bus-frequency", bus);
+        }
+}
+
+void dt_fixup_clock(const char *path, u32 freq)
+{
+        void *devp = finddevice(path);
+
+        if (devp) {
+                printf("%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
+                setprop_val(devp, "clock-frequency", freq);
+        }
+}
+
+void __dt_fixup_mac_addresses(u32 startindex, ...)
+{
+        va_list ap;
+        u32 index = startindex;
+        void *devp;
+        const u8 *addr;
+
+        va_start(ap, startindex);
+        while ((addr = va_arg(ap, const u8 *))) {
+                devp = find_node_by_prop_value(NULL, "linux,network-index",
+                                               (void*)&index, sizeof(index));
+
+                printf("ENET%d: local-mac-address <-"
+                       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
+                       addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
+
+                if (devp)
+                        setprop(devp, "local-mac-address", addr, 6);
+
+                index++;
+        }
+        va_end(ap);
+}
diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
index e1df8feaf16d..ab9dfe2b38f1 100644
--- a/arch/powerpc/boot/main.c
+++ b/arch/powerpc/boot/main.c
@@ -153,13 +153,10 @@ static struct addr_range prep_kernel(void)
         return (struct addr_range){addr, ei.memsize};
 }
 
-static struct addr_range prep_initrd(struct addr_range vmlinux,
+static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen,
                                      unsigned long initrd_addr,
                                      unsigned long initrd_size)
 {
-        void *devp;
-        u32 initrd_start, initrd_end;
-
         /* If we have an image attached to us, it overrides anything
          * supplied by the loader. */
         if (_initrd_end > _initrd_start) {
@@ -198,16 +195,8 @@ static struct addr_range prep_initrd(struct addr_range vmlinux,
         printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr));
 
         /* Tell the kernel initrd address via device tree */
-        devp = finddevice("/chosen");
-        if (! devp)
-                fatal("Device tree has no chosen node!\n\r");
-
-        initrd_start = (u32)initrd_addr;
-        initrd_end = (u32)initrd_addr + initrd_size;
-
-        setprop(devp, "linux,initrd-start", &initrd_start,
-                sizeof(initrd_start));
-        setprop(devp, "linux,initrd-end", &initrd_end, sizeof(initrd_end));
+        setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr));
+        setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size));
 
         return (struct addr_range){(void *)initrd_addr, initrd_size};
 }
@@ -254,6 +243,7 @@ void start(void)
         kernel_entry_t kentry;
         char cmdline[COMMAND_LINE_SIZE];
         unsigned long ft_addr = 0;
+        void *chosen;
 
         if (console_ops.open && (console_ops.open() < 0))
                 exit();
@@ -263,9 +253,14 @@ void start(void)
         printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r",
                _start, get_sp());
 
+        /* Ensure that the device tree has a /chosen node */
+        chosen = finddevice("/chosen");
+        if (!chosen)
+                chosen = create_node(NULL, "chosen");
+
         vmlinux = prep_kernel();
-        initrd = prep_initrd(vmlinux, loader_info.initrd_addr,
-                             loader_info.initrd_size);
+        initrd = prep_initrd(vmlinux, chosen,
+                             loader_info.initrd_addr, loader_info.initrd_size);
 
         /* If cmdline came from zimage wrapper or if we can edit the one
          * in the dt, print it out and edit it, if possible.
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
index 592dc6c20bdb..cc191e8e147f 100644
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -96,6 +96,11 @@ static inline int setprop(void *devp, const char *name,
 {
         return (dt_ops.setprop) ? dt_ops.setprop(devp, name, buf, buflen) : -1;
 }
+#define setprop_val(devp, name, val) \
+        do { \
+                typeof(val) x = (val); \
+                setprop((devp), (name), &x, sizeof(x)); \
+        } while (0)
 
 static inline int setprop_str(void *devp, const char *name, const char *buf)
 {
@@ -141,6 +146,14 @@ static inline void *find_node_by_devtype(const void *prev,
         return find_node_by_prop_value_str(prev, "device_type", type);
 }
 
+void dt_fixup_memory(u64 start, u64 size);
+void dt_fixup_cpu_clocks(u32 cpufreq, u32 tbfreq, u32 busfreq);
+void dt_fixup_clock(const char *path, u32 freq);
+void __dt_fixup_mac_addresses(u32 startindex, ...);
+#define dt_fixup_mac_addresses(...) \
+        __dt_fixup_mac_addresses(0, __VA_ARGS__, NULL)
+
+
 static inline void *malloc(u32 size)
 {
         return (platform_ops.malloc) ? platform_ops.malloc(size) : NULL;