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-rw-r--r--arch/microblaze/kernel/prom.c1147
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, &reg);
+ size = dt_mem_next_cell(dt_root_size_cells, &reg);
+
+ 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
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