prom_init.c

linux 内核源代码

		*mem_start = _ALIGN(*mem_start, 4);
	}

	/* Add a "linux,phandle" property. */
	soff = dt_find_string(RELOC("linux,phandle"));
	if (soff == 0)
		prom_printf("WARNING: Can't find string index for"
			    " <linux-phandle> node %s\n", path);
	else {
		dt_push_token(OF_DT_PROP, mem_start, mem_end);
		dt_push_token(4, mem_start, mem_end);
		dt_push_token(soff, mem_start, mem_end);
		valp = make_room(mem_start, mem_end, 4, 4);
		*(u32 *)valp = node;
	}

	/* do all our children */
	child = call_prom("child", 1, 1, node);
	while (child != 0) {
		scan_dt_build_struct(child, mem_start, mem_end);
		child = call_prom("peer", 1, 1, child);
	}

	dt_push_token(OF_DT_END_NODE, mem_start, mem_end);
}

static void __init flatten_device_tree(void)
{
	phandle root;
	unsigned long mem_start, mem_end, room;
	struct boot_param_header *hdr;
	struct prom_t *_prom = &RELOC(prom);
	char *namep;
	u64 *rsvmap;

	/*
	 * Check how much room we have between alloc top & bottom (+/- a
	 * few pages), crop to 4Mb, as this is our "chuck" size
	 */
	room = RELOC(alloc_top) - RELOC(alloc_bottom) - 0x4000;
	if (room > DEVTREE_CHUNK_SIZE)
		room = DEVTREE_CHUNK_SIZE;
	prom_debug("starting device tree allocs at %x\n", RELOC(alloc_bottom));

	/* Now try to claim that */
	mem_start = (unsigned long)alloc_up(room, PAGE_SIZE);
	if (mem_start == 0)
		prom_panic("Can't allocate initial device-tree chunk\n");
	mem_end = RELOC(alloc_top);

	/* Get root of tree */
	root = call_prom("peer", 1, 1, (phandle)0);
	if (root == (phandle)0)
		prom_panic ("couldn't get device tree root\n");

	/* Build header and make room for mem rsv map */ 
	mem_start = _ALIGN(mem_start, 4);
	hdr = make_room(&mem_start, &mem_end,
			sizeof(struct boot_param_header), 4);
	RELOC(dt_header_start) = (unsigned long)hdr;
	rsvmap = make_room(&mem_start, &mem_end, sizeof(mem_reserve_map), 8);

	/* Start of strings */
	mem_start = PAGE_ALIGN(mem_start);
	RELOC(dt_string_start) = mem_start;
	mem_start += 4; /* hole */

	/* Add "linux,phandle" in there, we'll need it */
	namep = make_room(&mem_start, &mem_end, 16, 1);
	strcpy(namep, RELOC("linux,phandle"));
	mem_start = (unsigned long)namep + strlen(namep) + 1;

	/* Build string array */
	prom_printf("Building dt strings...\n"); 
	scan_dt_build_strings(root, &mem_start, &mem_end);
	RELOC(dt_string_end) = mem_start;

	/* Build structure */
	mem_start = PAGE_ALIGN(mem_start);
	RELOC(dt_struct_start) = mem_start;
	prom_printf("Building dt structure...\n"); 
	scan_dt_build_struct(root, &mem_start, &mem_end);
	dt_push_token(OF_DT_END, &mem_start, &mem_end);
	RELOC(dt_struct_end) = PAGE_ALIGN(mem_start);

	/* Finish header */
	hdr->boot_cpuid_phys = _prom->cpu;
	hdr->magic = OF_DT_HEADER;
	hdr->totalsize = RELOC(dt_struct_end) - RELOC(dt_header_start);
	hdr->off_dt_struct = RELOC(dt_struct_start) - RELOC(dt_header_start);
	hdr->off_dt_strings = RELOC(dt_string_start) - RELOC(dt_header_start);
	hdr->dt_strings_size = RELOC(dt_string_end) - RELOC(dt_string_start);
	hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - RELOC(dt_header_start);
	hdr->version = OF_DT_VERSION;
	/* Version 16 is not backward compatible */
	hdr->last_comp_version = 0x10;

	/* Copy the reserve map in */
	memcpy(rsvmap, RELOC(mem_reserve_map), sizeof(mem_reserve_map));

#ifdef DEBUG_PROM
	{
		int i;
		prom_printf("reserved memory map:\n");
		for (i = 0; i < RELOC(mem_reserve_cnt); i++)
			prom_printf("  %x - %x\n",
				    RELOC(mem_reserve_map)[i].base,
				    RELOC(mem_reserve_map)[i].size);
	}
#endif
	/* Bump mem_reserve_cnt to cause further reservations to fail
	 * since it's too late.
	 */
	RELOC(mem_reserve_cnt) = MEM_RESERVE_MAP_SIZE;

	prom_printf("Device tree strings 0x%x -> 0x%x\n",
		    RELOC(dt_string_start), RELOC(dt_string_end)); 
	prom_printf("Device tree struct  0x%x -> 0x%x\n",
		    RELOC(dt_struct_start), RELOC(dt_struct_end));

}

#ifdef CONFIG_PPC_MAPLE
/* PIBS Version 1.05.0000 04/26/2005 has an incorrect /ht/isa/ranges property.
 * The values are bad, and it doesn't even have the right number of cells. */
static void __init fixup_device_tree_maple(void)
{
	phandle isa;
	u32 rloc = 0x01002000; /* IO space; PCI device = 4 */
	u32 isa_ranges[6];
	char *name;

	name = "/ht@0/isa@4";
	isa = call_prom("finddevice", 1, 1, ADDR(name));
	if (!PHANDLE_VALID(isa)) {
		name = "/ht@0/isa@6";
		isa = call_prom("finddevice", 1, 1, ADDR(name));
		rloc = 0x01003000; /* IO space; PCI device = 6 */
	}
	if (!PHANDLE_VALID(isa))
		return;

	if (prom_getproplen(isa, "ranges") != 12)
		return;
	if (prom_getprop(isa, "ranges", isa_ranges, sizeof(isa_ranges))
		== PROM_ERROR)
		return;

	if (isa_ranges[0] != 0x1 ||
		isa_ranges[1] != 0xf4000000 ||
		isa_ranges[2] != 0x00010000)
		return;

	prom_printf("Fixing up bogus ISA range on Maple/Apache...\n");

	isa_ranges[0] = 0x1;
	isa_ranges[1] = 0x0;
	isa_ranges[2] = rloc;
	isa_ranges[3] = 0x0;
	isa_ranges[4] = 0x0;
	isa_ranges[5] = 0x00010000;
	prom_setprop(isa, name, "ranges",
			isa_ranges, sizeof(isa_ranges));
}
#else
#define fixup_device_tree_maple()
#endif

#ifdef CONFIG_PPC_CHRP
/*
 * Pegasos and BriQ lacks the "ranges" property in the isa node
 * Pegasos needs decimal IRQ 14/15, not hexadecimal
 * Pegasos has the IDE configured in legacy mode, but advertised as native
 */
static void __init fixup_device_tree_chrp(void)
{
	phandle ph;
	u32 prop[6];
	u32 rloc = 0x01006000; /* IO space; PCI device = 12 */
	char *name;
	int rc;

	name = "/pci@80000000/isa@c";
	ph = call_prom("finddevice", 1, 1, ADDR(name));
	if (!PHANDLE_VALID(ph)) {
		name = "/pci@ff500000/isa@6";
		ph = call_prom("finddevice", 1, 1, ADDR(name));
		rloc = 0x01003000; /* IO space; PCI device = 6 */
	}
	if (PHANDLE_VALID(ph)) {
		rc = prom_getproplen(ph, "ranges");
		if (rc == 0 || rc == PROM_ERROR) {
			prom_printf("Fixing up missing ISA range on Pegasos...\n");

			prop[0] = 0x1;
			prop[1] = 0x0;
			prop[2] = rloc;
			prop[3] = 0x0;
			prop[4] = 0x0;
			prop[5] = 0x00010000;
			prom_setprop(ph, name, "ranges", prop, sizeof(prop));
		}
	}

	name = "/pci@80000000/ide@C,1";
	ph = call_prom("finddevice", 1, 1, ADDR(name));
	if (PHANDLE_VALID(ph)) {
		prom_printf("Fixing up IDE interrupt on Pegasos...\n");
		prop[0] = 14;
		prop[1] = 0x0;
		prom_setprop(ph, name, "interrupts", prop, 2*sizeof(u32));
		prom_printf("Fixing up IDE class-code on Pegasos...\n");
		rc = prom_getprop(ph, "class-code", prop, sizeof(u32));
		if (rc == sizeof(u32)) {
			prop[0] &= ~0x5;
			prom_setprop(ph, name, "class-code", prop, sizeof(u32));
		}
	}
}
#else
#define fixup_device_tree_chrp()
#endif

#if defined(CONFIG_PPC64) && defined(CONFIG_PPC_PMAC)
static void __init fixup_device_tree_pmac(void)
{
	phandle u3, i2c, mpic;
	u32 u3_rev;
	u32 interrupts[2];
	u32 parent;

	/* Some G5s have a missing interrupt definition, fix it up here */
	u3 = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000"));
	if (!PHANDLE_VALID(u3))
		return;
	i2c = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000/i2c@f8001000"));
	if (!PHANDLE_VALID(i2c))
		return;
	mpic = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000/mpic@f8040000"));
	if (!PHANDLE_VALID(mpic))
		return;

	/* check if proper rev of u3 */
	if (prom_getprop(u3, "device-rev", &u3_rev, sizeof(u3_rev))
	    == PROM_ERROR)
		return;
	if (u3_rev < 0x35 || u3_rev > 0x39)
		return;
	/* does it need fixup ? */
	if (prom_getproplen(i2c, "interrupts") > 0)
		return;

	prom_printf("fixing up bogus interrupts for u3 i2c...\n");

	/* interrupt on this revision of u3 is number 0 and level */
	interrupts[0] = 0;
	interrupts[1] = 1;
	prom_setprop(i2c, "/u3@0,f8000000/i2c@f8001000", "interrupts",
		     &interrupts, sizeof(interrupts));
	parent = (u32)mpic;
	prom_setprop(i2c, "/u3@0,f8000000/i2c@f8001000", "interrupt-parent",
		     &parent, sizeof(parent));
}
#else
#define fixup_device_tree_pmac()
#endif

#ifdef CONFIG_PPC_EFIKA
/* The current fw of the Efika has a device tree needs quite a few
 * fixups to be compliant with the mpc52xx bindings. It's currently
 * unknown if it will ever be compliant (come on bPlan ...) so we do fixups.
 * NOTE that we (barely) tolerate it because the EFIKA was out before
 * the bindings were finished, for any new boards -> RTFM ! */

struct subst_entry {
	char *path;
	char *property;
	void *value;
	int value_len;
};

static void __init fixup_device_tree_efika(void)
{
	/* Substitution table */
	#define prop_cstr(x) x, sizeof(x)
	int prop_sound_irq[3] = { 2, 2, 0 };
	int prop_bcomm_irq[3*16] = { 3,0,0, 3,1,0, 3,2,0, 3,3,0,
	                             3,4,0, 3,5,0, 3,6,0, 3,7,0,
	                             3,8,0, 3,9,0, 3,10,0, 3,11,0,
	                             3,12,0, 3,13,0, 3,14,0, 3,15,0 };
	struct subst_entry efika_subst_table[] = {
		{ "/",			"device_type",	prop_cstr("efika") },
		{ "/builtin",		"device_type",	prop_cstr("soc") },
		{ "/builtin/ata",	"compatible",	prop_cstr("mpc5200b-ata\0mpc5200-ata"), },
		{ "/builtin/bestcomm",	"compatible",	prop_cstr("mpc5200b-bestcomm\0mpc5200-bestcomm") },
		{ "/builtin/bestcomm",	"interrupts",	prop_bcomm_irq, sizeof(prop_bcomm_irq) },
		{ "/builtin/ethernet",	"compatible",	prop_cstr("mpc5200b-fec\0mpc5200-fec") },
		{ "/builtin/pic",	"compatible",	prop_cstr("mpc5200b-pic\0mpc5200-pic") },
		{ "/builtin/serial",	"compatible",	prop_cstr("mpc5200b-psc-uart\0mpc5200-psc-uart") },
		{ "/builtin/sound",	"compatible",	prop_cstr("mpc5200b-psc-ac97\0mpc5200-psc-ac97") },
		{ "/builtin/sound",	"interrupts",	prop_sound_irq, sizeof(prop_sound_irq) },
		{ "/builtin/sram",	"compatible",	prop_cstr("mpc5200b-sram\0mpc5200-sram") },
		{ "/builtin/sram",	"device_type",	prop_cstr("sram") },
		{}
	};
	#undef prop_cstr

	/* Vars */
	u32 node;
	char prop[64];
	int rv, i;

	/* Check if we're really running on a EFIKA */
	node = call_prom("finddevice", 1, 1, ADDR("/"));
	if (!PHANDLE_VALID(node))
		return;

	rv = prom_getprop(node, "model", prop, sizeof(prop));
	if (rv == PROM_ERROR)
		return;
	if (strcmp(prop, "EFIKA5K2"))
		return;

	prom_printf("Applying EFIKA device tree fixups\n");

	/* Process substitution table */
	for (i=0; efika_subst_table[i].path; i++) {
		struct subst_entry *se = &efika_subst_table[i];

		node = call_prom("finddevice", 1, 1, ADDR(se->path));
		if (!PHANDLE_VALID(node)) {
			prom_printf("fixup_device_tree_efika: ",
				"skipped entry %x - not found\n", i);
			continue;
		}

		rv = prom_setprop(node, se->path, se->property,
					se->value, se->value_len );
		if (rv == PROM_ERROR)
			prom_printf("fixup_device_tree_efika: ",
				"skipped entry %x - setprop error\n", i);
	}

	/* Make sure ethernet mdio bus node exists */
	node = call_prom("finddevice", 1, 1, ADDR("/builtin/mdio"));
	if (!PHANDLE_VALID(node)) {
		prom_printf("Adding Ethernet MDIO node\n");
		call_prom("interpret", 1, 1,
			" s\" /builtin\" find-device"
			" new-device"
				" 1 encode-int s\" #address-cells\" property"
				" 0 encode-int s\" #size-cells\" property"
				" s\" mdio\" 2dup device-name device-type"
				" s\" mpc5200b-fec-phy\" encode-string"
				" s\" compatible\" property"
				" 0xf0003000 0x400 reg"
				" 0x2 encode-int"
				" 0x5 encode-int encode+"
				" 0x3 encode-int encode+"
				" s\" interrupts\" property"
			" finish-device");
	};

	/* Make sure ethernet phy device node exist */
	node = call_prom("finddevice", 1, 1, ADDR("/builtin/mdio/ethernet-phy"));
	if (!PHANDLE_VALID(node)) {
		prom_printf("Adding Ethernet PHY node\n");
		call_prom("interpret", 1, 1,
			" s\" /builtin/mdio\" find-device"
			" new-device"
				" s\" ethernet-phy\" device-name"
				" 0x10 encode-int s\" reg\" property"
				" my-self"
				" ihandle>phandle"
			" finish-device"
			" s\" /builtin/ethernet\" find-device"
				" encode-int"
				" s\" phy-handle\" property"
			" device-end");
	}

}
#else
#define fixup_device_tree_efika()
#endif

static void __init fixup_device_tree(void)
{
	fixup_device_tree_maple();
	fixup_device_tree_chrp();
	fixup_device_tree_pmac();
	fixup_device_tree_efika();
}

static void __init prom_find_boot_cpu(void)
{
	struct prom_t *_prom = &RELOC(prom);
	u32 getprop_rval;
	ihandle prom_cpu;
	phandle cpu_pkg;

	_prom->cpu = 0;
	if (prom_getprop(_prom->chosen, "cpu", &prom_cpu, sizeof(prom_cpu)) <= 0)
		return;

	cpu_pkg = call_prom("instance-to-package", 1, 1, prom_cpu);

	prom_getprop(cpu_pkg, "reg", &getprop_rval, sizeof(getprop_rval));
	_prom->cpu = getprop_rval;

	prom_debug("Booting CPU hw index = 0x%x\n", _prom->cpu);
}

static void __init prom_check_initrd(unsigned long r3, unsigned long r4)
{
#ifdef CONFIG_BLK_DEV_INITRD
	struct prom_t *_prom = &RELOC(prom);

	if (r3 && r4 && r4 != 0xdeadbeef) {
		unsigned long val;

		RELOC(prom_initrd_start) = is_kernel_addr(r3) ? __pa(r3) : r3;
		RELOC(prom_initrd_end) = RELOC(prom_initrd_start) + r4;

		val = RELOC(prom_initrd_start);
		prom_setprop(_prom->chosen, "/chosen", "linux,initrd-start",
			     &val, sizeof(val));
		val = RELOC(prom_initrd_end);
		prom_setprop(_prom->chosen, "/chosen", "linux,initrd-end",
			     &val, sizeof(val));

		reserve_mem(RELOC(prom_initrd_start),
			    RELOC(prom_initrd_end) - RELOC(prom_initrd_start));

		prom_debug("initrd_start=0x%x\n", RELOC(prom_initrd_start));
		prom_debug("initrd_end=0x%x\n", RELOC(prom_initrd_end));
	}
#endif /* CONFIG_BLK_DEV_INITRD */
}

/*
 * We enter here early on, when the Open Firmware prom is still
 * handling exceptions and the MMU hash table for us.
 */

unsigned long __init prom_init(unsigned long r3, unsigned long r4,
			       unsigned long pp,
			       unsigned long r6, unsigned long r7)
{	
	struct prom_t *_prom;
	unsigned long hdr;
	unsigned long offset = reloc_offset();

#ifdef CONFIG_PPC32
	reloc_got2(offset);
#endif

	_prom = &RELOC(prom);

	/*
	 * First zero the BSS
	 */
	memset(&RELOC(__bss_start), 0, __bss_stop - __bss_start);

	/*
	 * Init interface to Open Firmware, get some node references