of: assume big-endian properties, adding conversions where necessary

Properties in the device tree are specified as big-endian. At present,
the only platforms to support device trees are also big-endian, so we've
been acessing the properties as raw values.

We'd like to add device tree support to little-endian platforms too, so
add endian conversion to the sites where we access property values in
the common of code.

Compiled on powerpc (ppc44x_defconfig & ppc64_defconfig) and arm (fdt
support only for now).

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

6 files changed, 47 insertions, 41 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 524645ab42a4..873479a21c80 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -38,7 +38,7 @@ int of_n_addr_cells(struct device_node *np)
                         np = np->parent;
                 ip = of_get_property(np, "#address-cells", NULL);
                 if (ip)
-                        return *ip;
+                        return be32_to_cpup(ip);
         } while (np->parent);
         /* No #address-cells property for the root node */
         return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
@@ -54,7 +54,7 @@ int of_n_size_cells(struct device_node *np)
                         np = np->parent;
                 ip = of_get_property(np, "#size-cells", NULL);
                 if (ip)
-                        return *ip;
+                        return be32_to_cpup(ip);
         } while (np->parent);
         /* No #size-cells property for the root node */
         return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
@@ -696,8 +696,8 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
                                 const void **out_args)
 {
         int ret = -EINVAL;
-        const u32 *list;
-        const u32 *list_end;
+        const __be32 *list;
+        const __be32 *list_end;
         int size;
         int cur_index = 0;
         struct device_node *node = NULL;
@@ -711,7 +711,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
         list_end = list + size / sizeof(*list);
 
         while (list < list_end) {
-                const u32 *cells;
+                const __be32 *cells;
                 const phandle *phandle;
 
                 phandle = list++;
@@ -735,7 +735,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
                         goto err1;
                 }
 
-                list += *cells;
+                list += be32_to_cpup(cells);
                 if (list > list_end) {
                         pr_debug("%s: insufficient arguments length\n",
                                  np->full_name);
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 968a86af5301..5c5f03ef7f06 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -51,7 +51,7 @@ int __init of_scan_flat_dt(int (*it)(unsigned long node,
         int depth = -1;
 
         do {
-                u32 tag = *((u32 *)p);
+                u32 tag = be32_to_cpup((__be32 *)p);
                 char *pathp;
 
                 p += 4;
@@ -64,7 +64,7 @@ int __init of_scan_flat_dt(int (*it)(unsigned long node,
                 if (tag == OF_DT_END)
                         break;
                 if (tag == OF_DT_PROP) {
-                        u32 sz = *((u32 *)p);
+                        u32 sz = be32_to_cpup((__be32 *)p);
                         p += 8;
                         if (initial_boot_params->version < 0x10)
                                 p = _ALIGN(p, sz >= 8 ? 8 : 4);
@@ -103,9 +103,9 @@ unsigned long __init of_get_flat_dt_root(void)
         unsigned long p = ((unsigned long)initial_boot_params) +
                 initial_boot_params->off_dt_struct;
 
-        while (*((u32 *)p) == OF_DT_NOP)
+        while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
                 p += 4;
-        BUG_ON(*((u32 *)p) != OF_DT_BEGIN_NODE);
+        BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
         p += 4;
         return _ALIGN(p + strlen((char *)p) + 1, 4);
 }
@@ -122,7 +122,7 @@ void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
         unsigned long p = node;
 
         do {
-                u32 tag = *((u32 *)p);
+                u32 tag = be32_to_cpup((__be32 *)p);
                 u32 sz, noff;
                 const char *nstr;
 
@@ -132,8 +132,8 @@ void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
                 if (tag != OF_DT_PROP)
                         return NULL;
 
-                sz = *((u32 *)p);
-                noff = *((u32 *)(p + 4));
+                sz = be32_to_cpup((__be32 *)p);
+                noff = be32_to_cpup((__be32 *)(p + 4));
                 p += 8;
                 if (initial_boot_params->version < 0x10)
                         p = _ALIGN(p, sz >= 8 ? 8 : 4);
@@ -210,7 +210,7 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
         int has_name = 0;
         int new_format = 0;
 
-        tag = *((u32 *)(*p));
+        tag = be32_to_cpup((__be32 *)(*p));
         if (tag != OF_DT_BEGIN_NODE) {
                 pr_err("Weird tag at start of node: %x\n", tag);
                 return mem;
@@ -285,7 +285,7 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
                 u32 sz, noff;
                 char *pname;
 
-                tag = *((u32 *)(*p));
+                tag = be32_to_cpup((__be32 *)(*p));
                 if (tag == OF_DT_NOP) {
                         *p += 4;
                         continue;
@@ -293,8 +293,8 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
                 if (tag != OF_DT_PROP)
                         break;
                 *p += 4;
-                sz = *((u32 *)(*p));
-                noff = *((u32 *)((*p) + 4));
+                sz = be32_to_cpup((__be32 *)(*p));
+                noff = be32_to_cpup((__be32 *)((*p) + 4));
                 *p += 8;
                 if (initial_boot_params->version < 0x10)
                         *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
@@ -367,7 +367,7 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
         }
         while (tag == OF_DT_BEGIN_NODE) {
                 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
-                tag = *((u32 *)(*p));
+                tag = be32_to_cpup((__be32 *)(*p));
         }
         if (tag != OF_DT_END_NODE) {
                 pr_err("Weird tag at end of node: %x\n", tag);
@@ -385,7 +385,7 @@ unsigned long __init unflatten_dt_node(unsigned long mem,
 void __init early_init_dt_check_for_initrd(unsigned long node)
 {
         unsigned long start, end, len;
-        u32 *prop;
+        __be32 *prop;
 
         pr_debug("Looking for initrd properties... ");
 
@@ -414,17 +414,22 @@ inline void early_init_dt_check_for_initrd(unsigned long node)
 int __init early_init_dt_scan_root(unsigned long node, const char *uname,
                                    int depth, void *data)
 {
-        u32 *prop;
+        __be32 *prop;
 
         if (depth != 0)
                 return 0;
 
+        dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+        dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+
         prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
-        dt_root_size_cells = prop ? *prop : OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+        if (prop)
+                dt_root_size_cells = be32_to_cpup(prop);
         pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
 
         prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
-        dt_root_addr_cells = prop ? *prop : OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+        if (prop)
+                dt_root_addr_cells = be32_to_cpup(prop);
         pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
 
         /* break now */
@@ -549,7 +554,7 @@ void __init unflatten_device_tree(void)
         mem = lmb_alloc(size + 4, __alignof__(struct device_node));
         mem = (unsigned long) __va(mem);
 
-        ((u32 *)mem)[size / 4] = 0xdeadbeef;
+        ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
 
         pr_debug("  unflattening %lx...\n", mem);
 
@@ -557,11 +562,11 @@ void __init unflatten_device_tree(void)
         start = ((unsigned long)initial_boot_params) +
                 initial_boot_params->off_dt_struct;
         unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
-        if (*((u32 *)start) != OF_DT_END)
+        if (be32_to_cpup((__be32 *)start) != OF_DT_END)
                 pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start));
-        if (((u32 *)mem)[size / 4] != 0xdeadbeef)
+        if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef)
                 pr_warning("End of tree marker overwritten: %08x\n",
-                           ((u32 *)mem)[size / 4]);
+                           be32_to_cpu(((__be32 *)mem)[size / 4]));
         *allnextp = NULL;
 
         /* Get pointer to OF "/chosen" node for use everywhere */
diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c
index 6eea601a9204..24c3606217f8 100644
--- a/drivers/of/gpio.c
+++ b/drivers/of/gpio.c
@@ -36,7 +36,7 @@ int of_get_gpio_flags(struct device_node *np, int index,
         struct of_gpio_chip *of_gc = NULL;
         int size;
         const void *gpio_spec;
-        const u32 *gpio_cells;
+        const __be32 *gpio_cells;
 
         ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells", index,
                                           &gc, &gpio_spec);
@@ -55,7 +55,7 @@ int of_get_gpio_flags(struct device_node *np, int index,
 
         gpio_cells = of_get_property(gc, "#gpio-cells", &size);
         if (!gpio_cells || size != sizeof(*gpio_cells) ||
-                        *gpio_cells != of_gc->gpio_cells) {
+                        be32_to_cpup(gpio_cells) != of_gc->gpio_cells) {
                 pr_debug("%s: wrong #gpio-cells for %s\n",
                          np->full_name, gc->full_name);
                 ret = -EINVAL;
@@ -127,7 +127,8 @@ EXPORT_SYMBOL(of_gpio_count);
 int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
                          const void *gpio_spec, enum of_gpio_flags *flags)
 {
-        const u32 *gpio = gpio_spec;
+        const __be32 *gpio = gpio_spec;
+        const u32 n = be32_to_cpup(gpio);
 
         /*
          * We're discouraging gpio_cells < 2, since that way you'll have to
@@ -140,13 +141,13 @@ int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
                 return -EINVAL;
         }
 
-        if (*gpio > of_gc->gc.ngpio)
+        if (n > of_gc->gc.ngpio)
                 return -EINVAL;
 
         if (flags)
-                *flags = gpio[1];
+                *flags = be32_to_cpu(gpio[1]);
 
-        return *gpio;
+        return n;
 }
 EXPORT_SYMBOL(of_gpio_simple_xlate);
 
diff --git a/drivers/of/of_i2c.c b/drivers/of/of_i2c.c
index fa65a2b2ae2e..a3a708e590d0 100644
--- a/drivers/of/of_i2c.c
+++ b/drivers/of/of_i2c.c
@@ -25,7 +25,7 @@ void of_register_i2c_devices(struct i2c_adapter *adap,
         for_each_child_of_node(adap_node, node) {
                 struct i2c_board_info info = {};
                 struct dev_archdata dev_ad = {};
-                const u32 *addr;
+                const __be32 *addr;
                 int len;
 
                 if (of_modalias_node(node, info.type, sizeof(info.type)) < 0)
@@ -40,7 +40,7 @@ void of_register_i2c_devices(struct i2c_adapter *adap,
 
                 info.irq = irq_of_parse_and_map(node, 0);
 
-                info.addr = *addr;
+                info.addr = be32_to_cpup(addr);
 
                 dev_archdata_set_node(&dev_ad, node);
                 info.archdata = &dev_ad;
diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 4b22ba568b19..18ecae4a4375 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -51,7 +51,7 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 
         /* Loop over the child nodes and register a phy_device for each one */
         for_each_child_of_node(np, child) {
-                const u32 *addr;
+                const __be32 *addr;
                 int len;
 
                 /* A PHY must have a reg property in the range [0-31] */
@@ -68,7 +68,7 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
                                 mdio->irq[*addr] = PHY_POLL;
                 }
 
-                phy = get_phy_device(mdio, *addr);
+                phy = get_phy_device(mdio, be32_to_cpup(addr));
                 if (!phy) {
                         dev_err(&mdio->dev, "error probing PHY at address %i\n",
                                 *addr);
@@ -160,7 +160,7 @@ struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
         struct device_node *net_np;
         char bus_id[MII_BUS_ID_SIZE + 3];
         struct phy_device *phy;
-        const u32 *phy_id;
+        const __be32 *phy_id;
         int sz;
 
         if (!dev->dev.parent)
@@ -174,7 +174,7 @@ struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
         if (!phy_id || sz < sizeof(*phy_id))
                 return NULL;
 
-        sprintf(bus_id, PHY_ID_FMT, "0", phy_id[0]);
+        sprintf(bus_id, PHY_ID_FMT, "0", be32_to_cpu(phy_id[0]));
 
         phy = phy_connect(dev, bus_id, hndlr, 0, iface);
         return IS_ERR(phy) ? NULL : phy;
diff --git a/drivers/of/of_spi.c b/drivers/of/of_spi.c
index bed0ed6dcdc1..f65f48b98448 100644
--- a/drivers/of/of_spi.c
+++ b/drivers/of/of_spi.c
@@ -23,7 +23,7 @@ void of_register_spi_devices(struct spi_master *master, struct device_node *np)
 {
         struct spi_device *spi;
         struct device_node *nc;
-        const u32 *prop;
+        const __be32 *prop;
         int rc;
         int len;
 
@@ -54,7 +54,7 @@ void of_register_spi_devices(struct spi_master *master, struct device_node *np)
                         spi_dev_put(spi);
                         continue;
                 }
-                spi->chip_select = *prop;
+                spi->chip_select = be32_to_cpup(prop);
 
                 /* Mode (clock phase/polarity/etc.) */
                 if (of_find_property(nc, "spi-cpha", NULL))
@@ -72,7 +72,7 @@ void of_register_spi_devices(struct spi_master *master, struct device_node *np)
                         spi_dev_put(spi);
                         continue;
                 }
-                spi->max_speed_hz = *prop;
+                spi->max_speed_hz = be32_to_cpup(prop);
 
                 /* IRQ */
                 spi->irq = irq_of_parse_and_map(nc, 0);