prom.c

来自「linux2.6.16版本」· C语言 代码 · 共 1,974 行 · 第 1/4 页

	if (0 == size)
		end = start = 0;
	else
		end = start = (unsigned long)__va(lmb_alloc(size, 128));

	finish_node(allnodes, &end, 0);
	BUG_ON(end != start + size);

	DBG(" <- finish_device_tree\n");
}

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;
}

/**
 * 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);
}

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 *p = np->full_name;
			/* rebuild full path for new format */
			if (dad && dad->parent) {
				strcpy(p, dad->full_name);
#ifdef DEBUG
				if ((strlen(p) + l + 1) != allocl) {
					DBG("%s: p: %d, l: %d, a: %d\n",
					    pathp, strlen(p), l, allocl);
				}
#endif
				p += strlen(p);
			}
			*(p++) = '/';
			memcpy(p, 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 == 0)
				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("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 *p = pathp, *ps = pathp, *pa = NULL;
		int sz;

		while (*p) {
			if ((*p) == '@')
				pa = p;
			if ((*p) == '/')
				ps = p + 1;
			p++;
		}
		if (pa < ps)
			pa = p;
		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 = (unsigned char *)(pp + 1);
			*prev_pp = pp;
			prev_pp = &pp->next;
			memcpy(pp->value, ps, sz - 1);
			((char *)pp->value)[sz - 1] = 0;
			DBG("fixed up name for %s -> %s\n", pathp, pp->value);
		}
	}
	if (allnextpp) {
		*prev_pp = NULL;
		np->name = get_property(np, "name", NULL);
		np->type = 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("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;

	DBG(" -> 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;

	DBG("  size is %lx, allocating...\n", size);

	/* Allocate memory for the expanded device tree */
	mem = lmb_alloc(size + 4, __alignof__(struct device_node));
	if (!mem) {
		DBG("Couldn't allocate memory with lmb_alloc()!\n");
		panic("Couldn't allocate memory with lmb_alloc()!\n");
	}
	mem = (unsigned long) __va(mem);

	((u32 *)mem)[size / 4] = 0xdeadbeef;

	DBG("  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");

	DBG(" <- unflatten_device_tree()\n");
}


static int __init early_init_dt_scan_cpus(unsigned long node,
					  const char *uname, int depth, void *data)
{
	u32 *prop;
	unsigned long size;
	char *type = of_get_flat_dt_prop(node, "device_type", &size);

	/* We are scanning "cpu" nodes only */
	if (type == NULL || strcmp(type, "cpu") != 0)
		return 0;

	boot_cpuid = 0;
	boot_cpuid_phys = 0;
	if (initial_boot_params && initial_boot_params->version >= 2) {
		/* version 2 of the kexec param format adds the phys cpuid
		 * of booted proc.
		 */
		boot_cpuid_phys = initial_boot_params->boot_cpuid_phys;
	} else {
		/* Check if it's the boot-cpu, set it's hw index now */
		if (of_get_flat_dt_prop(node,
					"linux,boot-cpu", NULL) != NULL) {
			prop = of_get_flat_dt_prop(node, "reg", NULL);
			if (prop != NULL)
				boot_cpuid_phys = *prop;
		}
	}
	set_hard_smp_processor_id(0, boot_cpuid_phys);

#ifdef CONFIG_ALTIVEC
	/* Check if we have a VMX and eventually update CPU features */
	prop = (u32 *)of_get_flat_dt_prop(node, "ibm,vmx", NULL);
	if (prop && (*prop) > 0) {
		cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
		cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
	}

	/* Same goes for Apple's "altivec" property */
	prop = (u32 *)of_get_flat_dt_prop(node, "altivec", NULL);
	if (prop) {
		cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
		cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
	}
#endif /* CONFIG_ALTIVEC */

#ifdef CONFIG_PPC_PSERIES
	/*
	 * Check for an SMT capable CPU and set the CPU feature. We do
	 * this by looking at the size of the ibm,ppc-interrupt-server#s
	 * property
	 */
	prop = (u32 *)of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s",
				       &size);
	cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
	if (prop && ((size / sizeof(u32)) > 1))
		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
#endif

	return 0;
}

static int __init early_init_dt_scan_chosen(unsigned long node,
					    const char *uname, int depth, void *data)
{
	u32 *prop;
	unsigned long *lprop;
	unsigned long l;
	char *p;

	DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);

	if (depth != 1 ||
	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
		return 0;

	/* get platform type */
	prop = (u32 *)of_get_flat_dt_prop(node, "linux,platform", NULL);
	if (prop == NULL)
		return 0;
#ifdef CONFIG_PPC_MULTIPLATFORM
	_machine = *prop;
#endif

#ifdef CONFIG_PPC64
	/* check if iommu is forced on or off */
	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
		iommu_is_off = 1;
	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
		iommu_force_on = 1;
#endif

 	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 	if (lprop)
 		memory_limit = *lprop;

#ifdef CONFIG_PPC64
 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 	if (lprop)
 		tce_alloc_start = *lprop;
 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 	if (lprop)
 		tce_alloc_end = *lprop;
#endif

#ifdef CONFIG_PPC_RTAS
	/* To help early debugging via the front panel, we retrieve a minimal
	 * set of RTAS infos now if available
	 */
	{
		u64 *basep, *entryp;

		basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
		entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
		prop = of_get_flat_dt_prop(node, "linux,rtas-size", NULL);
		if (basep && entryp && prop) {
			rtas.base = *basep;
			rtas.entry = *entryp;
			rtas.size = *prop;
		}
	}
#endif /* CONFIG_PPC_RTAS */

#ifdef CONFIG_KEXEC
       lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
       if (lprop)
               crashk_res.start = *lprop;