diff options
Diffstat (limited to 'target/linux/olpc/files/arch/i386/kernel/prom.c')
-rw-r--r-- | target/linux/olpc/files/arch/i386/kernel/prom.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/target/linux/olpc/files/arch/i386/kernel/prom.c b/target/linux/olpc/files/arch/i386/kernel/prom.c new file mode 100644 index 000000000..d64bb276f --- /dev/null +++ b/target/linux/olpc/files/arch/i386/kernel/prom.c @@ -0,0 +1,478 @@ +/* + * Procedures for creating, accessing and interpreting the device tree. + * + * Paul Mackerras August 1996. + * Copyright (C) 1996-2005 Paul Mackerras. + * + * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. + * {engebret|bergner}@us.ibm.com + * + * Adapted for sparc64 by David S. Miller davem@davemloft.net + * + * Adapter for i386/OLPC by Andres Salomon <dilinger@debian.org> + * + * 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 <linux/kernel.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/bootmem.h> +#include <linux/module.h> +#include <asm/prom.h> +#include <asm/ofw.h> + +/* + * XXX: This is very much a stub; right now we're keeping 2 device trees + * in memory (one for promfs, and one here). That will not remain + * for long! + */ + +static struct device_node *allnodes; + +/* use when traversing tree through the allnext, child, sibling, + * or parent members of struct device_node. + */ +static DEFINE_RWLOCK(devtree_lock); + +int of_device_is_compatible(const struct device_node *device, + const char *compat) +{ + const char* cp; + int cplen, l; + + cp = of_get_property(device, "compatible", &cplen); + if (cp == NULL) + return 0; + while (cplen > 0) { + if (strncmp(cp, compat, strlen(compat)) == 0) + return 1; + l = strlen(cp) + 1; + cp += l; + cplen -= l; + } + + return 0; +} +EXPORT_SYMBOL(of_device_is_compatible); + +struct device_node *of_get_parent(const struct device_node *node) +{ + struct device_node *np; + + if (!node) + return NULL; + + np = node->parent; + + return np; +} +EXPORT_SYMBOL(of_get_parent); + +struct device_node *of_get_next_child(const struct device_node *node, + struct device_node *prev) +{ + struct device_node *next; + + next = prev ? prev->sibling : node->child; + for (; next != 0; next = next->sibling) { + break; + } + + return next; +} +EXPORT_SYMBOL(of_get_next_child); + +struct device_node *of_find_node_by_path(const char *path) +{ + struct device_node *np = allnodes; + + for (; np != 0; np = np->allnext) { + if (np->full_name != 0 && strcmp(np->full_name, path) == 0) + break; + } + + return np; +} +EXPORT_SYMBOL(of_find_node_by_path); + +struct device_node *of_find_node_by_phandle(phandle handle) +{ + struct device_node *np; + + for (np = allnodes; np != 0; np = np->allnext) + if (np->node == handle) + break; + + return np; +} +EXPORT_SYMBOL(of_find_node_by_phandle); + +struct device_node *of_find_node_by_name(struct device_node *from, + const char *name) +{ + struct device_node *np; + + np = from ? from->allnext : allnodes; + for (; np != NULL; np = np->allnext) + if (np->name != NULL && strcmp(np->name, name) == 0) + break; + + return np; +} +EXPORT_SYMBOL(of_find_node_by_name); + +struct device_node *of_find_node_by_type(struct device_node *from, + const char *type) +{ + struct device_node *np; + + np = from ? from->allnext : allnodes; + for (; np != 0; np = np->allnext) + if (np->type != 0 && strcmp(np->type, type) == 0) + break; + + return np; +} +EXPORT_SYMBOL(of_find_node_by_type); + +struct device_node *of_find_compatible_node(struct device_node *from, + const char *type, const char *compatible) +{ + struct device_node *np; + + np = from ? from->allnext : allnodes; + for (; np != 0; np = np->allnext) { + if (type != NULL + && !(np->type != 0 && strcmp(np->type, type) == 0)) + continue; + if (of_device_is_compatible(np, compatible)) + break; + } + + return np; +} +EXPORT_SYMBOL(of_find_compatible_node); + +struct property *of_find_property(const struct device_node *np, + const char *name, + int *lenp) +{ + struct property *pp; + + for (pp = np->properties; pp != 0; pp = pp->next) { + if (strcasecmp(pp->name, name) == 0) { + if (lenp != 0) + *lenp = pp->length; + break; + } + } + return pp; +} +EXPORT_SYMBOL(of_find_property); + +/* + * Find a property with a given name for a given node + * and return the value. + */ +const void *of_get_property(const struct device_node *np, const char *name, + int *lenp) +{ + struct property *pp = of_find_property(np,name,lenp); + return pp ? pp->value : NULL; +} +EXPORT_SYMBOL(of_get_property); + +int of_getintprop_default(struct device_node *np, const char *name, int def) +{ + struct property *prop; + int len; + + prop = of_find_property(np, name, &len); + if (!prop || len != 4) + return def; + + return *(int *) prop->value; +} +EXPORT_SYMBOL(of_getintprop_default); + +int of_n_addr_cells(struct device_node *np) +{ + const int* ip; + do { + if (np->parent) + np = np->parent; + ip = of_get_property(np, "#address-cells", NULL); + if (ip != NULL) + return *ip; + } while (np->parent); + /* No #address-cells property for the root node, default to 2 */ + return 2; +} +EXPORT_SYMBOL(of_n_addr_cells); + +int of_n_size_cells(struct device_node *np) +{ + const int* ip; + do { + if (np->parent) + np = np->parent; + ip = of_get_property(np, "#size-cells", NULL); + if (ip != NULL) + return *ip; + } while (np->parent); + /* No #size-cells property for the root node, default to 1 */ + return 1; +} +EXPORT_SYMBOL(of_n_size_cells); + +int of_set_property(struct device_node *dp, const char *name, void *val, int len) +{ + return -EIO; +} +EXPORT_SYMBOL(of_set_property); + +static unsigned int prom_early_allocated; + +static void * __init prom_early_alloc(unsigned long size) +{ + void *ret; + + ret = kmalloc(size, GFP_KERNEL); + if (ret != NULL) + memset(ret, 0, size); + else + printk(KERN_ERR "ACK! couldn't allocate prom memory!\n"); + + prom_early_allocated += size; + + return ret; +} + +static int is_root_node(const struct device_node *dp) +{ + if (!dp) + return 0; + + return (dp->parent == NULL); +} + +static char * __init build_path_component(struct device_node *dp) +{ + int pathlen; + char *n, *i; + + if (ofw("package-to-path", 3, 1, dp->node, NULL, 0, &pathlen)) { + printk(KERN_ERR "PROM: unable to get path name from OFW!\n"); + return "ERROR"; + } + n = prom_early_alloc(pathlen + 1); + if (ofw("package-to-path", 3, 1, dp->node, n, pathlen+1, &pathlen)) + printk(KERN_ERR "PROM: unable to get path name from OFW\n"); + + if ((i = strrchr(n, '/'))) + n = ++i; /* we only want the file name */ + return n; +} + +static char * __init build_full_name(struct device_node *dp) +{ + int len, ourlen, plen; + char *n; + + plen = strlen(dp->parent->full_name); + ourlen = strlen(dp->path_component_name); + len = ourlen + plen + 2; + + n = prom_early_alloc(len); + strcpy(n, dp->parent->full_name); + if (!is_root_node(dp->parent)) { + strcpy(n + plen, "/"); + plen++; + } + strcpy(n + plen, dp->path_component_name); + + return n; +} + +static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len) +{ + static struct property *tmp = NULL; + struct property *p; + + if (tmp) { + p = tmp; + memset(p, 0, sizeof(*p) + 32); + tmp = NULL; + } else { + p = prom_early_alloc(sizeof(struct property) + 32); + } + + p->name = (char *) (p + 1); + if (special_name) { + strcpy(p->name, special_name); + p->length = special_len; + p->value = prom_early_alloc(special_len); + memcpy(p->value, special_val, special_len); + } else { + int fl; + if (prev == NULL) { + if (ofw("nextprop", 3, 1, node, "", p->name, &fl)) { + printk(KERN_ERR "PROM: %s: nextprop failed!\n", __func__); + return NULL; + } + } else { + if (ofw("nextprop", 3, 1, node, prev, p->name, &fl)) { + printk(KERN_ERR "PROM: %s: nextprop failed!\n", __func__); + return NULL; + } + } + if (strlen(p->name) == 0 || fl != 1) { + tmp = p; + return NULL; + } + if (ofw("getproplen", 2, 1, node, p->name, &p->length)) { + printk(KERN_ERR "PROM: %s: getproplen failed!\n", __func__); + return NULL; + } + if (p->length <= 0) { + p->length = 0; + } else { + p->value = prom_early_alloc(p->length + 1); + if (ofw("getprop", 4, 1, node, p->name, p->value, p->length, &p->length)) { + printk(KERN_ERR "PROM: %s: getprop failed!\n", __func__); + return NULL; + } + ((unsigned char *)p->value)[p->length] = '\0'; + } + } + return p; +} + +static struct property * __init build_prop_list(phandle node) +{ + struct property *head, *tail; + + head = tail = build_one_prop(node, NULL, + ".node", &node, sizeof(node)); + + tail->next = build_one_prop(node, NULL, NULL, NULL, 0); + tail = tail->next; + while(tail) { + tail->next = build_one_prop(node, tail->name, + NULL, NULL, 0); + tail = tail->next; + } + + return head; +} + +static char * __init get_one_property(phandle node, const char *name) +{ + char *buf = "<NULL>"; + int len; + + if (ofw("getproplen", 2, 1, node, name, &len)) { + printk(KERN_ERR "PROM: %s: getproplen failed!\n", __func__); + return NULL; + } + if (len > 0) { + buf = prom_early_alloc(len); + if (ofw("getprop", 4, 1, node, name, buf, len, &len)) { + printk(KERN_ERR "PROM: %s: getprop failed!\n", __func__); + return NULL; + } + } + + return buf; +} + +static struct device_node * __init create_node(phandle node, struct device_node *parent) +{ + struct device_node *dp; + + if (!node) + return NULL; + + dp = prom_early_alloc(sizeof(*dp)); + dp->parent = parent; + + kref_init(&dp->kref); + + dp->name = get_one_property(node, "name"); + dp->type = get_one_property(node, "device_type"); + dp->node = node; + + dp->properties = build_prop_list(node); + + return dp; +} + +static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp) +{ + struct device_node *ret = NULL, *prev_sibling = NULL; + struct device_node *dp; + u32 child; + + while (1) { + dp = create_node(node, parent); + if (!dp) + break; + + if (prev_sibling) + prev_sibling->sibling = dp; + + if (!ret) + ret = dp; + prev_sibling = dp; + + *(*nextp) = dp; + *nextp = &dp->allnext; + + dp->path_component_name = build_path_component(dp); + dp->full_name = build_full_name(dp); + + if (ofw("child", 1, 1, node, &child)) { + printk(KERN_ERR "PROM: %s: fetching child failed!\n", __func__); + return NULL; + } + dp->child = build_tree(dp, child, nextp); + + if (ofw("peer", 1, 1, node, &node)) { + printk(KERN_ERR "PROM: %s: fetching peer failed!\n", __func__); + return NULL; + } + } + + return ret; +} + +static phandle root_node; + +void __init prom_build_devicetree(void) +{ + struct device_node **nextp; + u32 child; + + if (ofw("peer", 1, 1, 0, &root_node)) { + printk(KERN_ERR "PROM: unable to get root node from OFW!\n"); + return; + } + + allnodes = create_node(root_node, NULL); + allnodes->path_component_name = ""; + allnodes->full_name = "/"; + + nextp = &allnodes->allnext; + if (ofw("child", 1, 1, allnodes->node, &child)) { + printk(KERN_ERR "PROM: unable to get child node from OFW!\n"); + return; + } + allnodes->child = build_tree(allnodes, child, &nextp); + printk("PROM: Built device tree with %u bytes of memory.\n", + prom_early_allocated); +} |