prom.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

		 * On a CHRP we have an 8259 which is subordinate to
		 * the openpic in the interrupt tree, but we want the
		 * openpic's interrupt numbers offsetted, not the 8259's.
		 * So we apply the offset if the controller is at the
		 * root of the interrupt tree, i.e. has no interrupt-parent.
		 * This doesn't cope with the general case of multiple
		 * cascaded interrupt controllers, but then neither will
		 * irq.c at the moment either.  -- paulus
		 */
		if (num_interrupt_controllers > 1 && ic != NULL
		    && get_property(ic, "interrupt-parent", NULL) == NULL)
			offset = 16;
		np->intrs[i].line = irq[0] + offset;
		if (n > 1)
			np->intrs[i].sense = irq[1];
		if (n > 2) {
			printk("hmmm, got %d intr cells for %s:", n,
			       np->full_name);
			for (j = 0; j < n; ++j)
				printk(" %d", irq[j]);
			printk("\n");
		}
		ints += intrcells;
	}

	return mem_start;
}

/*
 * When BootX makes a copy of the device tree from the MacOS
 * Name Registry, it is in the format we use but all of the pointers
 * are offsets from the start of the tree.
 * This procedure updates the pointers.
 */
void __init
relocate_nodes(void)
{
	unsigned long base;
	struct device_node *np;
	struct property *pp;

#define ADDBASE(x)	(x = (x)? ((typeof (x))((unsigned long)(x) + base)): 0)

	base = (unsigned long) boot_infos + boot_infos->deviceTreeOffset;
	allnodes = (struct device_node *)(base + 4);
	for (np = allnodes; np != 0; np = np->allnext) {
		ADDBASE(np->full_name);
		ADDBASE(np->properties);
		ADDBASE(np->parent);
		ADDBASE(np->child);
		ADDBASE(np->sibling);
		ADDBASE(np->allnext);
		for (pp = np->properties; pp != 0; pp = pp->next) {
			ADDBASE(pp->name);
			ADDBASE(pp->value);
			ADDBASE(pp->next);
		}
	}
}

int
prom_n_addr_cells(struct device_node* np)
{
	int* ip;
	do {
		if (np->parent)
			np = np->parent;
		ip = (int *) get_property(np, "#address-cells", 0);
		if (ip != NULL)
			return *ip;
	} while (np->parent);
	/* No #address-cells property for the root node, default to 1 */
	return 1;
}

int
prom_n_size_cells(struct device_node* np)
{
	int* ip;
	do {
		if (np->parent)
			np = np->parent;
		ip = (int *) get_property(np, "#size-cells", 0);
		if (ip != NULL)
			return *ip;
	} while (np->parent);
	/* No #size-cells property for the root node, default to 1 */
	return 1;
}

static unsigned long __init
map_addr(struct device_node *np, unsigned long space, unsigned long addr)
{
	int na;
	unsigned int *ranges;
	int rlen = 0;
	unsigned int type;

	type = (space >> 24) & 3;
	if (type == 0)
		return addr;

	while ((np = np->parent) != NULL) {
		if (strcmp(np->type, "pci") != 0)
			continue;
		/* PCI bridge: map the address through the ranges property */
		na = prom_n_addr_cells(np);
		ranges = (unsigned int *) get_property(np, "ranges", &rlen);
		while ((rlen -= (na + 5) * sizeof(unsigned int)) >= 0) {
			if (((ranges[0] >> 24) & 3) == type
			    && ranges[2] <= addr
			    && addr - ranges[2] < ranges[na+4]) {
				/* ok, this matches, translate it */
				addr += ranges[na+2] - ranges[2];
				break;
			}
			ranges += na + 5;
		}
	}
	return addr;
}

static unsigned long __init
interpret_pci_props(struct device_node *np, unsigned long mem_start,
		    int naddrc, int nsizec)
{
	struct address_range *adr;
	struct pci_reg_property *pci_addrs;
	int i, l, *ip;

	pci_addrs = (struct pci_reg_property *)
		get_property(np, "assigned-addresses", &l);
	if (pci_addrs != 0 && l >= sizeof(struct pci_reg_property)) {
		i = 0;
		adr = (struct address_range *) mem_start;
		while ((l -= sizeof(struct pci_reg_property)) >= 0) {
			adr[i].space = pci_addrs[i].addr.a_hi;
			adr[i].address = map_addr(np, pci_addrs[i].addr.a_hi,
						  pci_addrs[i].addr.a_lo);
			adr[i].size = pci_addrs[i].size_lo;
			++i;
		}
		np->addrs = adr;
		np->n_addrs = i;
		mem_start += i * sizeof(struct address_range);
	}

	if (use_of_interrupt_tree)
		return mem_start;

	ip = (int *) get_property(np, "AAPL,interrupts", &l);
	if (ip == 0 && np->parent)
		ip = (int *) get_property(np->parent, "AAPL,interrupts", &l);
	if (ip == 0)
		ip = (int *) get_property(np, "interrupts", &l);
	if (ip != 0) {
		np->intrs = (struct interrupt_info *) mem_start;
		np->n_intrs = l / sizeof(int);
		mem_start += np->n_intrs * sizeof(struct interrupt_info);
		for (i = 0; i < np->n_intrs; ++i) {
			np->intrs[i].line = *ip++;
			np->intrs[i].sense = 1;
		}
	}

	return mem_start;
}

static unsigned long __init
interpret_dbdma_props(struct device_node *np, unsigned long mem_start,
		      int naddrc, int nsizec)
{
	struct reg_property *rp;
	struct address_range *adr;
	unsigned long base_address;
	int i, l, *ip;
	struct device_node *db;

	base_address = 0;
	for (db = np->parent; db != NULL; db = db->parent) {
		if (!strcmp(db->type, "dbdma") && db->n_addrs != 0) {
			base_address = db->addrs[0].address;
			break;
		}
	}

	rp = (struct reg_property *) get_property(np, "reg", &l);
	if (rp != 0 && l >= sizeof(struct reg_property)) {
		i = 0;
		adr = (struct address_range *) mem_start;
		while ((l -= sizeof(struct reg_property)) >= 0) {
			adr[i].space = 2;
			adr[i].address = rp[i].address + base_address;
			adr[i].size = rp[i].size;
			++i;
		}
		np->addrs = adr;
		np->n_addrs = i;
		mem_start += i * sizeof(struct address_range);
	}

	if (use_of_interrupt_tree)
		return mem_start;

	ip = (int *) get_property(np, "AAPL,interrupts", &l);
	if (ip == 0)
		ip = (int *) get_property(np, "interrupts", &l);
	if (ip != 0) {
		np->intrs = (struct interrupt_info *) mem_start;
		np->n_intrs = l / sizeof(int);
		mem_start += np->n_intrs * sizeof(struct interrupt_info);
		for (i = 0; i < np->n_intrs; ++i) {
			np->intrs[i].line = *ip++;
			np->intrs[i].sense = 1;
		}
	}

	return mem_start;
}

static unsigned long __init
interpret_macio_props(struct device_node *np, unsigned long mem_start,
		      int naddrc, int nsizec)
{
	struct reg_property *rp;
	struct address_range *adr;
	unsigned long base_address;
	int i, l, *ip;
	struct device_node *db;

	base_address = 0;
	for (db = np->parent; db != NULL; db = db->parent) {
		if (!strcmp(db->type, "mac-io") && db->n_addrs != 0) {
			base_address = db->addrs[0].address;
			break;
		}
	}

	rp = (struct reg_property *) get_property(np, "reg", &l);
	if (rp != 0 && l >= sizeof(struct reg_property)) {
		i = 0;
		adr = (struct address_range *) mem_start;
		while ((l -= sizeof(struct reg_property)) >= 0) {
			adr[i].space = 2;
			adr[i].address = rp[i].address + base_address;
			adr[i].size = rp[i].size;
			++i;
		}
		np->addrs = adr;
		np->n_addrs = i;
		mem_start += i * sizeof(struct address_range);
	}

	if (use_of_interrupt_tree)
		return mem_start;

	ip = (int *) get_property(np, "interrupts", &l);
	if (ip == 0)
		ip = (int *) get_property(np, "AAPL,interrupts", &l);
	if (ip != 0) {
		np->intrs = (struct interrupt_info *) mem_start;
		np->n_intrs = l / sizeof(int);
		for (i = 0; i < np->n_intrs; ++i) {
			np->intrs[i].line = *ip++;
			np->intrs[i].sense = 1;
		}
		mem_start += np->n_intrs * sizeof(struct interrupt_info);
	}

	return mem_start;
}

static unsigned long __init
interpret_isa_props(struct device_node *np, unsigned long mem_start,
		    int naddrc, int nsizec)
{
	struct isa_reg_property *rp;
	struct address_range *adr;
	int i, l, *ip;

	rp = (struct isa_reg_property *) get_property(np, "reg", &l);
	if (rp != 0 && l >= sizeof(struct isa_reg_property)) {
		i = 0;
		adr = (struct address_range *) mem_start;
		while ((l -= sizeof(struct reg_property)) >= 0) {
			adr[i].space = rp[i].space;
			adr[i].address = rp[i].address
				+ (adr[i].space? 0: _ISA_MEM_BASE);
			adr[i].size = rp[i].size;
			++i;
		}
		np->addrs = adr;
		np->n_addrs = i;
		mem_start += i * sizeof(struct address_range);
	}

	if (use_of_interrupt_tree)
		return mem_start;

	ip = (int *) get_property(np, "interrupts", &l);
	if (ip != 0) {
		np->intrs = (struct interrupt_info *) mem_start;
		np->n_intrs = l / (2 * sizeof(int));
		mem_start += np->n_intrs * sizeof(struct interrupt_info);
		for (i = 0; i < np->n_intrs; ++i) {
			np->intrs[i].line = *ip++;
			np->intrs[i].sense = *ip++;
		}
	}

	return mem_start;
}

static unsigned long __init
interpret_root_props(struct device_node *np, unsigned long mem_start,
		     int naddrc, int nsizec)
{
	struct address_range *adr;
	int i, l, *ip;
	unsigned int *rp;
	int rpsize = (naddrc + nsizec) * sizeof(unsigned int);

	rp = (unsigned int *) get_property(np, "reg", &l);
	if (rp != 0 && l >= rpsize) {
		i = 0;
		adr = (struct address_range *) mem_start;
		while ((l -= rpsize) >= 0) {
			adr[i].space = (naddrc >= 2? rp[naddrc-2]: 2);
			adr[i].address = rp[naddrc - 1];
			adr[i].size = rp[naddrc + nsizec - 1];
			++i;
			rp += naddrc + nsizec;
		}
		np->addrs = adr;
		np->n_addrs = i;
		mem_start += i * sizeof(struct address_range);
	}

	if (use_of_interrupt_tree)
		return mem_start;

	ip = (int *) get_property(np, "AAPL,interrupts", &l);
	if (ip == 0)
		ip = (int *) get_property(np, "interrupts", &l);
	if (ip != 0) {
		np->intrs = (struct interrupt_info *) mem_start;
		np->n_intrs = l / sizeof(int);
		mem_start += np->n_intrs * sizeof(struct interrupt_info);
		for (i = 0; i < np->n_intrs; ++i) {
			np->intrs[i].line = *ip++;
			np->intrs[i].sense = 1;
		}
	}

	return mem_start;
}

/*
 * Work out the sense (active-low level / active-high edge)
 * of each interrupt from the device tree.
 */
void __init
prom_get_irq_senses(unsigned char *senses, int off, int max)
{
	struct device_node *np;
	int i, j;

	/* default to level-triggered */
	memset(senses, 1, max - off);
	if (!use_of_interrupt_tree)
		return;

	for (np = allnodes; np != 0; np = np->allnext) {
		for (j = 0; j < np->n_intrs; j++) {
			i = np->intrs[j].line;
			if (i >= off && i < max) {
				if (np->intrs[j].sense == 1) {
					senses[i-off] = (IRQ_SENSE_LEVEL |
							IRQ_POLARITY_NEGATIVE);
				} else {
					senses[i-off] = (IRQ_SENSE_EDGE |
							IRQ_POLARITY_POSITIVE);
				}
			}
		}
	}
}

/*
 * Construct and return a list of the device_nodes with a given name.
 */
struct device_node *
find_devices(const char *name)
{
	struct device_node *head, **prevp, *np;

	prevp = &head;
	for (np = allnodes; np != 0; np = np->allnext) {
		if (np->name != 0 && strcasecmp(np->name, name) == 0) {
			*prevp = np;
			prevp = &np->next;
		}
	}
	*prevp = 0;
	return head;
}

/*
 * Construct and return a list of the device_nodes with a given type.
 */
struct device_node *
find_type_devices(const char *type)
{
	struct device_node *head, **prevp, *np;

	prevp = &head;
	for (np = allnodes; np != 0; np = np->allnext) {