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Diffstat (limited to 'arch/microblaze/kernel/prom.c')
| -rw-r--r-- | arch/microblaze/kernel/prom.c | 1147 |
1 files changed, 1147 insertions, 0 deletions
diff --git a/arch/microblaze/kernel/prom.c b/arch/microblaze/kernel/prom.c new file mode 100644 index 000000000000..475b1fac5cfd --- /dev/null +++ b/arch/microblaze/kernel/prom.c @@ -0,0 +1,1147 @@ +/* + * 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 + * + * 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 <linux/kernel.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/threads.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <linux/pci.h> +#include <linux/stringify.h> +#include <linux/delay.h> +#include <linux/initrd.h> +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/kexec.h> +#include <linux/debugfs.h> +#include <linux/irq.h> +#include <linux/lmb.h> + +#include <asm/prom.h> +#include <asm/page.h> +#include <asm/processor.h> +#include <asm/irq.h> +#include <linux/io.h> +#include <asm/system.h> +#include <asm/mmu.h> +#include <asm/pgtable.h> +#include <linux/pci.h> +#include <asm/sections.h> +#include <asm/pci-bridge.h> + +static int __initdata dt_root_addr_cells; +static int __initdata dt_root_size_cells; + +typedef u32 cell_t; + +static struct boot_param_header *initial_boot_params; + +/* export that to outside world */ +struct device_node *of_chosen; + +static inline char *find_flat_dt_string(u32 offset) +{ + return ((char *)initial_boot_params) + + initial_boot_params->off_dt_strings + offset; +} + +/** + * This function is used to scan the flattened device-tree, it is + * used to extract the memory informations at boot before we can + * unflatten the tree + */ +int __init of_scan_flat_dt(int (*it)(unsigned long node, + const char *uname, int depth, + void *data), + void *data) +{ + unsigned long p = ((unsigned long)initial_boot_params) + + initial_boot_params->off_dt_struct; + int rc = 0; + int depth = -1; + + do { + u32 tag = *((u32 *)p); + char *pathp; + + p += 4; + if (tag == OF_DT_END_NODE) { + depth--; + continue; + } + if (tag == OF_DT_NOP) + continue; + if (tag == OF_DT_END) + break; + if (tag == OF_DT_PROP) { + u32 sz = *((u32 *)p); + p += 8; + if (initial_boot_params->version < 0x10) + p = _ALIGN(p, sz >= 8 ? 8 : 4); + p += sz; + p = _ALIGN(p, 4); + continue; + } + if (tag != OF_DT_BEGIN_NODE) { + printk(KERN_WARNING "Invalid tag %x scanning flattened" + " device tree !\n", tag); + return -EINVAL; + } + depth++; + pathp = (char *)p; + p = _ALIGN(p + strlen(pathp) + 1, 4); + if ((*pathp) == '/') { + char *lp, *np; + for (lp = NULL, np = pathp; *np; np++) + if ((*np) == '/') + lp = np+1; + if (lp != NULL) + pathp = lp; + } + rc = it(p, pathp, depth, data); + if (rc != 0) + break; + } while (1); + + return rc; +} + +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) + p += 4; + BUG_ON(*((u32 *)p) != OF_DT_BEGIN_NODE); + p += 4; + return _ALIGN(p + strlen((char *)p) + 1, 4); +} + +/** + * This function can be used within scan_flattened_dt callback to get + * access to properties + */ +void *__init of_get_flat_dt_prop(unsigned long node, const char *name, + unsigned long *size) +{ + unsigned long p = node; + + do { + u32 tag = *((u32 *)p); + u32 sz, noff; + const char *nstr; + + p += 4; + if (tag == OF_DT_NOP) + continue; + if (tag != OF_DT_PROP) + return NULL; + + sz = *((u32 *)p); + noff = *((u32 *)(p + 4)); + p += 8; + if (initial_boot_params->version < 0x10) + p = _ALIGN(p, sz >= 8 ? 8 : 4); + + nstr = find_flat_dt_string(noff); + if (nstr == NULL) { + printk(KERN_WARNING "Can't find property index" + " name !\n"); + return NULL; + } + if (strcmp(name, nstr) == 0) { + if (size) + *size = sz; + return (void *)p; + } + p += sz; + p = _ALIGN(p, 4); + } while (1); +} + +int __init of_flat_dt_is_compatible(unsigned long node, const char *compat) +{ + const char *cp; + unsigned long cplen, l; + + cp = of_get_flat_dt_prop(node, "compatible", &cplen); + if (cp == NULL) + return 0; + while (cplen > 0) { + if (strncasecmp(cp, compat, strlen(compat)) == 0) + return 1; + l = strlen(cp) + 1; + cp += l; + cplen -= l; + } + + return 0; +} + +static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size, + unsigned long align) +{ + void *res; + + *mem = _ALIGN(*mem, align); + res = (void *)*mem; + *mem += size; + + return res; +} + +static unsigned long __init unflatten_dt_node(unsigned long mem, + unsigned long *p, + struct device_node *dad, + struct device_node ***allnextpp, + unsigned long fpsize) +{ + struct device_node *np; + struct property *pp, **prev_pp = NULL; + char *pathp; + u32 tag; + unsigned int l, allocl; + int has_name = 0; + int new_format = 0; + + tag = *((u32 *)(*p)); + if (tag != OF_DT_BEGIN_NODE) { + printk("Weird tag at start of node: %x\n", tag); + return mem; + } + *p += 4; + pathp = (char *)*p; + l = allocl = strlen(pathp) + 1; + *p = _ALIGN(*p + l, 4); + + /* version 0x10 has a more compact unit name here instead of the full + * path. we accumulate the full path size using "fpsize", we'll rebuild + * it later. We detect this because the first character of the name is + * not '/'. + */ + if ((*pathp) != '/') { + new_format = 1; + if (fpsize == 0) { + /* root node: special case. fpsize accounts for path + * plus terminating zero. root node only has '/', so + * fpsize should be 2, but we want to avoid the first + * level nodes to have two '/' so we use fpsize 1 here + */ + fpsize = 1; + allocl = 2; + } else { + /* account for '/' and path size minus terminal 0 + * already in 'l' + */ + fpsize += l; + allocl = fpsize; + } + } + + np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl, + __alignof__(struct device_node)); + if (allnextpp) { + memset(np, 0, sizeof(*np)); + np->full_name = ((char *)np) + sizeof(struct device_node); + if (new_format) { + char *p2 = np->full_name; + /* rebuild full path for new format */ + if (dad && dad->parent) { + strcpy(p2, dad->full_name); +#ifdef DEBUG + if ((strlen(p2) + l + 1) != allocl) { + pr_debug("%s: p: %d, l: %d, a: %d\n", + pathp, (int)strlen(p2), + l, allocl); + } +#endif + p2 += strlen(p2); + } + *(p2++) = '/'; + memcpy(p2, pathp, l); + } else + memcpy(np->full_name, pathp, l); + prev_pp = &np->properties; + **allnextpp = np; + *allnextpp = &np->allnext; + if (dad != NULL) { + np->parent = dad; + /* we temporarily use the next field as `last_child'*/ + if (dad->next == NULL) + dad->child = np; + else + dad->next->sibling = np; + dad->next = np; + } + kref_init(&np->kref); + } + while (1) { + u32 sz, noff; + char *pname; + + tag = *((u32 *)(*p)); + if (tag == OF_DT_NOP) { + *p += 4; + continue; + } + if (tag != OF_DT_PROP) + break; + *p += 4; + sz = *((u32 *)(*p)); + noff = *((u32 *)((*p) + 4)); + *p += 8; + if (initial_boot_params->version < 0x10) + *p = _ALIGN(*p, sz >= 8 ? 8 : 4); + + pname = find_flat_dt_string(noff); + if (pname == NULL) { + printk(KERN_INFO + "Can't find property name in list !\n"); + break; + } + if (strcmp(pname, "name") == 0) + has_name = 1; + l = strlen(pname) + 1; + pp = unflatten_dt_alloc(&mem, sizeof(struct property), + __alignof__(struct property)); + if (allnextpp) { + if (strcmp(pname, "linux,phandle") == 0) { + np->node = *((u32 *)*p); + if (np->linux_phandle == 0) + np->linux_phandle = np->node; + } + if (strcmp(pname, "ibm,phandle") == 0) + np->linux_phandle = *((u32 *)*p); + pp->name = pname; + pp->length = sz; + pp->value = (void *)*p; + *prev_pp = pp; + prev_pp = &pp->next; + } + *p = _ALIGN((*p) + sz, 4); + } + /* with version 0x10 we may not have the name property, recreate + * it here from the unit name if absent + */ + if (!has_name) { + char *p1 = pathp, *ps = pathp, *pa = NULL; + int sz; + + while (*p1) { + if ((*p1) == '@') + pa = p1; + if ((*p1) == '/') + ps = p1 + 1; + p1++; + } + if (pa < ps) + pa = p1; + sz = (pa - ps) + 1; + pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz, + __alignof__(struct property)); + if (allnextpp) { + pp->name = "name"; + pp->length = sz; + pp->value = pp + 1; + *prev_pp = pp; + prev_pp = &pp->next; + memcpy(pp->value, ps, sz - 1); + ((char *)pp->value)[sz - 1] = 0; + pr_debug("fixed up name for %s -> %s\n", pathp, + (char *)pp->value); + } + } + if (allnextpp) { + *prev_pp = NULL; + np->name = of_get_property(np, "name", NULL); + np->type = of_get_property(np, "device_type", NULL); + + if (!np->name) + np->name = "<NULL>"; + if (!np->type) + np->type = "<NULL>"; + } + while (tag == OF_DT_BEGIN_NODE) { + mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize); + tag = *((u32 *)(*p)); + } + if (tag != OF_DT_END_NODE) { + printk(KERN_INFO "Weird tag at end of node: %x\n", tag); + return mem; + } + *p += 4; + return mem; +} + +/** + * unflattens the device-tree passed by the firmware, creating the + * tree of struct device_node. It also fills the "name" and "type" + * pointers of the nodes so the normal device-tree walking functions + * can be used (this used to be done by finish_device_tree) + */ +void __init unflatten_device_tree(void) +{ + unsigned long start, mem, size; + struct device_node **allnextp = &allnodes; + + pr_debug(" -> unflatten_device_tree()\n"); + + /* First pass, scan for size */ + start = ((unsigned long)initial_boot_params) + + initial_boot_params->off_dt_struct; + size = unflatten_dt_node(0, &start, NULL, NULL, 0); + size = (size | 3) + 1; + + pr_debug(" size is %lx, allocating...\n", size); + + /* Allocate memory for the expanded device tree */ + mem = lmb_alloc(size + 4, __alignof__(struct device_node)); + mem = (unsigned long) __va(mem); + + ((u32 *)mem)[size / 4] = 0xdeadbeef; + + pr_debug(" unflattening %lx...\n", mem); + + /* Second pass, do actual unflattening */ + 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) + printk(KERN_WARNING "Weird tag at end of tree: %08x\n", + *((u32 *)start)); + if (((u32 *)mem)[size / 4] != 0xdeadbeef) + printk(KERN_WARNING "End of tree marker overwritten: %08x\n", + ((u32 *)mem)[size / 4]); + *allnextp = NULL; + + /* Get pointer to OF "/chosen" node for use everywhere */ + of_chosen = of_find_node_by_path("/chosen"); + if (of_chosen == NULL) + of_chosen = of_find_node_by_path("/chosen@0"); + + pr_debug(" <- unflatten_device_tree()\n"); +} + +#define early_init_dt_scan_drconf_memory(node) 0 + +static int __init early_init_dt_scan_cpus(unsigned long node, + const char *uname, int depth, + void *data) +{ + static int logical_cpuid; + char *type = of_get_flat_dt_prop(node, "device_type", NULL); + const u32 *intserv; + int i, nthreads; + int found = 0; + + /* We are scanning "cpu" nodes only */ + if (type == NULL || strcmp(type, "cpu") != 0) + return 0; + + /* Get physical cpuid */ + intserv = of_get_flat_dt_prop(node, "reg", NULL); + nthreads = 1; + + /* + * Now see if any of these threads match our boot cpu. + * NOTE: This must match the parsing done in smp_setup_cpu_maps. + */ + for (i = 0; i < nthreads; i++) { + /* + * version 2 of the kexec param format adds the phys cpuid of + * booted proc. + */ + if (initial_boot_params && initial_boot_params->version >= 2) { + if (intserv[i] == + initial_boot_params->boot_cpuid_phys) { + found = 1; + break; + } + } else { + /* + * Check if it's the boot-cpu, set it's hw index now, + * unfortunately this format did not support booting + * off secondary threads. + */ + if (of_get_flat_dt_prop(node, + "linux,boot-cpu", NULL) != NULL) { + found = 1; + break; + } + } + +#ifdef CONFIG_SMP + /* logical cpu id is always 0 on UP kernels */ + logical_cpuid++; +#endif + } + + if (found) { + pr_debug("boot cpu: logical %d physical %d\n", logical_cpuid, + intserv[i]); + boot_cpuid = logical_cpuid; + } + + return 0; +} + +#ifdef CONFIG_BLK_DEV_INITRD +static void __init early_init_dt_check_for_initrd(unsigned long node) +{ + unsigned long l; + u32 *prop; + + pr_debug("Looking for initrd properties... "); + + prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l); + if (prop) { + initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4)); + + prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l); + if (prop) { + initrd_end = (unsigned long) + __va(of_read_ulong(prop, l/4)); + initrd_below_start_ok = 1; + } else { + initrd_start = 0; + } + } + + pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", + initrd_start, initrd_end); +} +#else +static inline void early_init_dt_check_for_initrd(unsigned long node) +{ +} +#endif /* CONFIG_BLK_DEV_INITRD */ + +static int __init early_init_dt_scan_chosen(unsigned long node, + const char *uname, int depth, void *data) +{ + unsigned long l; + char *p; + + pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); + + if (depth != 1 || + (strcmp(uname, "chosen") != 0 && + strcmp(uname, "chosen@0") != 0)) + return 0; + +#ifdef CONFIG_KEXEC + lprop = (u64 *)of_get_flat_dt_prop(node, + "linux,crashkernel-base", NULL); + if (lprop) + crashk_res.start = *lprop; + + lprop = (u64 *)of_get_flat_dt_prop(node, + "linux,crashkernel-size", NULL); + if (lprop) + crashk_res.end = crashk_res.start + *lprop - 1; +#endif + + early_init_dt_check_for_initrd(node); + + /* Retreive command line */ + p = of_get_flat_dt_prop(node, "bootargs", &l); + if (p != NULL && l > 0) + strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE)); + +#ifdef CONFIG_CMDLINE + if (p == NULL || l == 0 || (l == 1 && (*p) == 0)) + strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE); +#endif /* CONFIG_CMDLINE */ + + pr_debug("Command line is: %s\n", cmd_line); + + /* break now */ + return 1; +} + +static int __init early_init_dt_scan_root(unsigned long node, + const char *uname, int depth, void *data) +{ + u32 *prop; + + if (depth != 0) + return 0; + + prop = of_get_flat_dt_prop(node, "#size-cells", NULL); + dt_root_size_cells = (prop == NULL) ? 1 : *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 == NULL) ? 2 : *prop; + pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells); + + /* break now */ + return 1; +} + +static u64 __init dt_mem_next_cell(int s, cell_t **cellp) +{ + cell_t *p = *cellp; + + *cellp = p + s; + return of_read_number(p, s); +} + +static int __init early_init_dt_scan_memory(unsigned long node, + const char *uname, int depth, void *data) +{ + char *type = of_get_flat_dt_prop(node, "device_type", NULL); + cell_t *reg, *endp; + unsigned long l; + + /* Look for the ibm,dynamic-reconfiguration-memory node */ +/* if (depth == 1 && + strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) + return early_init_dt_scan_drconf_memory(node); +*/ + /* We are scanning "memory" nodes only */ + if (type == NULL) { + /* + * The longtrail doesn't have a device_type on the + * /memory node, so look for the node called /memory@0. + */ + if (depth != 1 || strcmp(uname, "memory@0") != 0) + return 0; + } else if (strcmp(type, "memory") != 0) + return 0; + + reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l); + if (reg == NULL) + reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l); + if (reg == NULL) + return 0; + + endp = reg + (l / sizeof(cell_t)); + + pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n", + uname, l, reg[0], reg[1], reg[2], reg[3]); + + while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { + u64 base, size; + + base = dt_mem_next_cell(dt_root_addr_cells, ®); + size = dt_mem_next_cell(dt_root_size_cells, ®); + + if (size == 0) + continue; + pr_debug(" - %llx , %llx\n", (unsigned long long)base, + (unsigned long long)size); + + lmb_add(base, size); + } + return 0; +} + +#ifdef CONFIG_PHYP_DUMP +/** + * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg + * + * Function to find the largest size we need to reserve + * during early boot process. + * + * It either looks for boot param and returns that OR + * returns larger of 256 or 5% rounded down to multiples of 256MB. + * + */ +static inline unsigned long phyp_dump_calculate_reserve_size(void) +{ + unsigned long tmp; + + if (phyp_dump_info->reserve_bootvar) + return phyp_dump_info->reserve_bootvar; + + /* divide by 20 to get 5% of value */ + tmp = lmb_end_of_DRAM(); + do_div(tmp, 20); + + /* round it down in multiples of 256 */ + tmp = tmp & ~0x0FFFFFFFUL; + + return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END); +} + +/** + * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory + * + * This routine may reserve memory regions in the kernel only + * if the system is supported and a dump was taken in last + * boot instance or if the hardware is supported and the + * scratch area needs to be setup. In other instances it returns + * without reserving anything. The memory in case of dump being + * active is freed when the dump is collected (by userland tools). + */ +static void __init phyp_dump_reserve_mem(void) +{ + unsigned long base, size; + unsigned long variable_reserve_size; + + if (!phyp_dump_info->phyp_dump_configured) { + printk(KERN_ERR "Phyp-dump not supported on this hardware\n"); + return; + } + + if (!phyp_dump_info->phyp_dump_at_boot) { + printk(KERN_INFO "Phyp-dump disabled at boot time\n"); + return; + } + + variable_reserve_size = phyp_dump_calculate_reserve_size(); + + if (phyp_dump_info->phyp_dump_is_active) { + /* Reserve *everything* above RMR.Area freed by userland tools*/ + base = variable_reserve_size; + size = lmb_end_of_DRAM() - base; + + /* XXX crashed_ram_end is wrong, since it may be beyond + * the memory_limit, it will need to be adjusted. */ + lmb_reserve(base, size); + + phyp_dump_info->init_reserve_start = base; + phyp_dump_info->init_reserve_size = size; + } else { + size = phyp_dump_info->cpu_state_size + + phyp_dump_info->hpte_region_size + + variable_reserve_size; + base = lmb_end_of_DRAM() - size; + lmb_reserve(base, size); + phyp_dump_info->init_reserve_start = base; + phyp_dump_info->init_reserve_size = size; + } +} +#else +static inline void __init phyp_dump_reserve_mem(void) {} +#endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */ + +#ifdef CONFIG_EARLY_PRINTK +/* MS this is Microblaze specifig function */ +static int __init early_init_dt_scan_serial(unsigned long node, + const char *uname, int depth, void *data) +{ + unsigned long l; + char *p; + int *addr; + + pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); + +/* find all serial nodes */ + if (strncmp(uname, "serial", 6) != 0) + return 0; + + early_init_dt_check_for_initrd(node); + +/* find compatible node with uartlite */ + p = of_get_flat_dt_prop(node, "compatible", &l); + if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) && + (strncmp(p, "xlnx,opb-uartlite", 17) != 0)) + return 0; + + addr = of_get_flat_dt_prop(node, "reg", &l); + return *addr; /* return address */ +} + +/* this function is looking for early uartlite console - Microblaze specific */ +int __init early_uartlite_console(void) +{ + return of_scan_flat_dt(early_init_dt_scan_serial, NULL); +} +#endif + +void __init early_init_devtree(void *params) +{ + pr_debug(" -> early_init_devtree(%p)\n", params); + + /* Setup flat device-tree pointer */ + initial_boot_params = params; + +#ifdef CONFIG_PHYP_DUMP + /* scan tree to see if dump occured during last boot */ + of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL); +#endif + + /* Retrieve various informations from the /chosen node of the + * device-tree, including the platform type, initrd location and + * size, TCE reserve, and more ... + */ + of_scan_flat_dt(early_init_dt_scan_chosen, NULL); + + /* Scan memory nodes and rebuild LMBs */ + lmb_init(); + of_scan_flat_dt(early_init_dt_scan_root, NULL); + of_scan_flat_dt(early_init_dt_scan_memory, NULL); + + /* Save command line for /proc/cmdline and then parse parameters */ + strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE); + parse_early_param(); + + lmb_analyze(); + + pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size()); + + pr_debug("Scanning CPUs ...\n"); + + /* Retreive CPU related informations from the flat tree + * (altivec support, boot CPU ID, ...) + */ + of_scan_flat_dt(early_init_dt_scan_cpus, NULL); + + pr_debug(" <- early_init_devtree()\n"); +} + +/** + * Indicates whether the root node has a given value in its + * compatible property. + */ +int machine_is_compatible(const char *compat) +{ + struct device_node *root; + int rc = 0; + + root = of_find_node_by_path("/"); + if (root) { + rc = of_device_is_compatible(root, compat); + of_node_put(root); + } + return rc; +} +EXPORT_SYMBOL(machine_is_compatible); + +/******* + * + * New implementation of the OF "find" APIs, return a refcounted + * object, call of_node_put() when done. The device tree and list + * are protected by a rw_lock. + * + * Note that property management will need some locking as well, + * this isn't dealt with yet. + * + *******/ + +/** + * of_find_node_by_phandle - Find a node given a phandle + * @handle: phandle of the node to find + * + * Returns a node pointer with refcount incremented, use + * of_node_put() on it when done. + */ +struct device_node *of_find_node_by_phandle(phandle handle) +{ + struct device_node *np; + + read_lock(&devtree_lock); + for (np = allnodes; np != NULL; np = np->allnext) + if (np->linux_phandle == handle) + break; + of_node_get(np); + read_unlock(&devtree_lock); + return np; +} +EXPORT_SYMBOL(of_find_node_by_phandle); + +/** + * of_find_all_nodes - Get next node in global list + * @prev: Previous node or NULL to start iteration + * of_node_put() will be called on it + * + * Returns a node pointer with refcount incremented, use + * of_node_put() on it when done. + */ +struct device_node *of_find_all_nodes(struct device_node *prev) +{ + struct device_node *np; + + read_lock(&devtree_lock); + np = prev ? prev->allnext : allnodes; + for (; np != NULL; np = np->allnext) + if (of_node_get(np)) + break; + of_node_put(prev); + read_unlock(&devtree_lock); + return np; +} +EXPORT_SYMBOL(of_find_all_nodes); + +/** + * of_node_get - Increment refcount of a node + * @node: Node to inc refcount, NULL is supported to + * simplify writing of callers + * + * Returns node. + */ +struct device_node *of_node_get(struct device_node *node) +{ + if (node) + kref_get(&node->kref); + return node; +} +EXPORT_SYMBOL(of_node_get); + +static inline struct device_node *kref_to_device_node(struct kref *kref) +{ + return container_of(kref, struct device_node, kref); +} + +/** + * of_node_release - release a dynamically allocated node + * @kref: kref element of the node to be released + * + * In of_node_put() this function is passed to kref_put() + * as the destructor. + */ +static void of_node_release(struct kref *kref) +{ + struct device_node *node = kref_to_device_node(kref); + struct property *prop = node->properties; + + /* We should never be releasing nodes that haven't been detached. */ + if (!of_node_check_flag(node, OF_DETACHED)) { + printk(KERN_INFO "WARNING: Bad of_node_put() on %s\n", + node->full_name); + dump_stack(); + kref_init(&node->kref); + return; + } + + if (!of_node_check_flag(node, OF_DYNAMIC)) + return; + + while (prop) { + struct property *next = prop->next; + kfree(prop->name); + kfree(prop->value); + kfree(prop); + prop = next; + + if (!prop) { + prop = node->deadprops; + node->deadprops = NULL; + } + } + kfree(node->full_name); + kfree(node->data); + kfree(node); +} + +/** + * of_node_put - Decrement refcount of a node + * @node: Node to dec refcount, NULL is supported to + * simplify writing of callers + * + */ +void of_node_put(struct device_node *node) +{ + if (node) + kref_put(&node->kref, of_node_release); +} +EXPORT_SYMBOL(of_node_put); + +/* + * Plug a device node into the tree and global list. + */ +void of_attach_node(struct device_node *np) +{ + unsigned long flags; + + write_lock_irqsave(&devtree_lock, flags); + np->sibling = np->parent->child; + np->allnext = allnodes; + np->parent->child = np; + allnodes = np; + write_unlock_irqrestore(&devtree_lock, flags); +} + +/* + * "Unplug" a node from the device tree. The caller must hold + * a reference to the node. The memory associated with the node + * is not freed until its refcount goes to zero. + */ +void of_detach_node(struct device_node *np) +{ + struct device_node *parent; + unsigned long flags; + + write_lock_irqsave(&devtree_lock, flags); + + parent = np->parent; + if (!parent) + goto out_unlock; + + if (allnodes == np) + allnodes = np->allnext; + else { + struct device_node *prev; + for (prev = allnodes; + prev->allnext != np; + prev = prev->allnext) + ; + prev->allnext = np->allnext; + } + + if (parent->child == np) + parent->child = np->sibling; + else { + struct device_node *prevsib; + for (prevsib = np->parent->child; + prevsib->sibling != np; + prevsib = prevsib->sibling) + ; + prevsib->sibling = np->sibling; + } + + of_node_set_flag(np, OF_DETACHED); + +out_unlock: + write_unlock_irqrestore(&devtree_lock, flags); +} + +/* + * Add a property to a node + */ +int prom_add_property(struct device_node *np, struct property *prop) +{ + struct property **next; + unsigned long flags; + + prop->next = NULL; + write_lock_irqsave(&devtree_lock, flags); + next = &np->properties; + while (*next) { + if (strcmp(prop->name, (*next)->name) == 0) { + /* duplicate ! don't insert it */ + write_unlock_irqrestore(&devtree_lock, flags); + return -1; + } + next = &(*next)->next; + } + *next = prop; + write_unlock_irqrestore(&devtree_lock, flags); + +#ifdef CONFIG_PROC_DEVICETREE + /* try to add to proc as well if it was initialized */ + if (np->pde) + proc_device_tree_add_prop(np->pde, prop); +#endif /* CONFIG_PROC_DEVICETREE */ + + return 0; +} + +/* + * Remove a property from a node. Note that we don't actually + * remove it, since we have given out who-knows-how-many pointers + * to the data using get-property. Instead we just move the property + * to the "dead properties" list, so it won't be found any more. + */ +int prom_remove_property(struct device_node *np, struct property *prop) +{ + struct property **next; + unsigned long flags; + int found = 0; + + write_lock_irqsave(&devtree_lock, flags); + next = &np->properties; + while (*next) { + if (*next == prop) { + /* found the node */ + *next = prop->next; + prop->next = np->deadprops; + np->deadprops = prop; + found = 1; + break; + } + next = &(*next)->next; + } + write_unlock_irqrestore(&devtree_lock, flags); + + if (!found) + return -ENODEV; + +#ifdef CONFIG_PROC_DEVICETREE + /* try to remove the proc node as well */ + if (np->pde) + proc_device_tree_remove_prop(np->pde, prop); +#endif /* CONFIG_PROC_DEVICETREE */ + + return 0; +} + +/* + * Update a property in a node. Note that we don't actually + * remove it, since we have given out who-knows-how-many pointers + * to the data using get-property. Instead we just move the property + * to the "dead properties" list, and add the new property to the + * property list + */ +int prom_update_property(struct device_node *np, + struct property *newprop, + struct property *oldprop) +{ + struct property **next; + unsigned long flags; + int found = 0; + + write_lock_irqsave(&devtree_lock, flags); + next = &np->properties; + while (*next) { + if (*next == oldprop) { + /* found the node */ + newprop->next = oldprop->next; + *next = newprop; + oldprop->next = np->deadprops; + np->deadprops = oldprop; + found = 1; + break; + } + next = &(*next)->next; + } + write_unlock_irqrestore(&devtree_lock, flags); + + if (!found) + return -ENODEV; + +#ifdef CONFIG_PROC_DEVICETREE + /* try to add to proc as well if it was initialized */ + if (np->pde) + proc_device_tree_update_prop(np->pde, newprop, oldprop); +#endif /* CONFIG_PROC_DEVICETREE */ + + return 0; +} + +#if defined(CONFIG_DEBUG_FS) && defined(DEBUG) +static struct debugfs_blob_wrapper flat_dt_blob; + +static int __init export_flat_device_tree(void) +{ + struct dentry *d; + + flat_dt_blob.data = initial_boot_params; + flat_dt_blob.size = initial_boot_params->totalsize; + + d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR, + of_debugfs_root, &flat_dt_blob); + if (!d) + return 1; + + return 0; +} +device_initcall(export_flat_device_tree); +#endif |
