prom_init.c

优龙2410linux2.6.8内核源代码

	if (strcmp(name, "valkyrie") == 0)
		address += 0x1000;

#ifdef CONFIG_POWER4
#if CONFIG_TASK_SIZE > 0x80000000
#error CONFIG_TASK_SIZE cannot be above 0x80000000 with BOOTX_TEXT on G5
#endif
	{
		extern boot_infos_t disp_bi;
		unsigned long va, pa, i, offset;
       		va = 0x90000000;
		pa = address & 0xfffff000ul;
		offset = address & 0x00000fff;

		for (i=0; i<0x4000; i++) {  
			make_pte((unsigned long)Hash - KERNELBASE, Hash_size, va, pa, 
				 _PAGE_ACCESSED | _PAGE_NO_CACHE |
				 _PAGE_GUARDED | PP_RWXX);
			va += 0x1000;
			pa += 0x1000;
		}
		btext_setup_display(width, height, depth, pitch, 0x90000000 | offset);
		disp_bi.dispDeviceBase = (u8 *)address;
	}
#else /* CONFIG_POWER4 */
	btext_setup_display(width, height, depth, pitch, address);
	btext_prepare_BAT();
#endif /* CONFIG_POWER4 */
#endif /* CONFIG_BOOTX_TEXT */
}

/*
 * Make a copy of the device tree from the PROM.
 */
static unsigned long __init
copy_device_tree(unsigned long mem_start, unsigned long mem_end)
{
	phandle root;
	unsigned long new_start;
	struct device_node **allnextp;

	root = call_prom("peer", 1, 1, (phandle)0);
	if (root == (phandle)0) {
		prom_print("couldn't get device tree root\n");
		prom_exit();
	}
	allnextp = &allnodes;
	mem_start = ALIGNUL(mem_start);
	new_start = inspect_node(root, NULL, mem_start, mem_end, &allnextp);
	*allnextp = NULL;
	return new_start;
}

static unsigned long __init
inspect_node(phandle node, struct device_node *dad,
	     unsigned long mem_start, unsigned long mem_end,
	     struct device_node ***allnextpp)
{
	int l;
	phandle child;
	struct device_node *np;
	struct property *pp, **prev_propp;
	char *prev_name, *namep;
	unsigned char *valp;

	np = (struct device_node *) mem_start;
	mem_start += sizeof(struct device_node);
	memset(np, 0, sizeof(*np));
	np->node = node;
	**allnextpp = PTRUNRELOC(np);
	*allnextpp = &np->allnext;
	if (dad != 0) {
		np->parent = PTRUNRELOC(dad);
		/* we temporarily use the `next' field as `last_child'. */
		if (dad->next == 0)
			dad->child = PTRUNRELOC(np);
		else
			dad->next->sibling = PTRUNRELOC(np);
		dad->next = np;
	}

	/* get and store all properties */
	prev_propp = &np->properties;
	prev_name = "";
	for (;;) {
		pp = (struct property *) mem_start;
		namep = (char *) (pp + 1);
		pp->name = PTRUNRELOC(namep);
		if ((int) call_prom("nextprop", 3, 1, node, prev_name,
				    namep) <= 0)
			break;
		mem_start = ALIGNUL((unsigned long)namep + strlen(namep) + 1);
		prev_name = namep;
		valp = (unsigned char *) mem_start;
		pp->value = PTRUNRELOC(valp);
		pp->length = (int)
			call_prom("getprop", 4, 1, node, namep,
				  valp, mem_end - mem_start);
		if (pp->length < 0)
			continue;
#ifdef MAX_PROPERTY_LENGTH
		if (pp->length > MAX_PROPERTY_LENGTH)
			continue; /* ignore this property */
#endif
		mem_start = ALIGNUL(mem_start + pp->length);
		*prev_propp = PTRUNRELOC(pp);
		prev_propp = &pp->next;
	}
	if (np->node != NULL) {
		/* Add a "linux,phandle" property" */
		pp = (struct property *) mem_start;
		*prev_propp = PTRUNRELOC(pp);
		prev_propp = &pp->next;
		namep = (char *) (pp + 1);
		pp->name = PTRUNRELOC(namep);
		strcpy(namep, "linux,phandle");
		mem_start = ALIGNUL((unsigned long)namep + strlen(namep) + 1);
		pp->value = (unsigned char *) PTRUNRELOC(&np->node);
		pp->length = sizeof(np->node);
	}
	*prev_propp = NULL;

	/* get the node's full name */
	l = (int) call_prom("package-to-path", 3, 1, node,
			    (char *) mem_start, mem_end - mem_start);
	if (l >= 0) {
		np->full_name = PTRUNRELOC((char *) mem_start);
		*(char *)(mem_start + l) = 0;
		mem_start = ALIGNUL(mem_start + l + 1);
	}

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

	return mem_start;
}

unsigned long smp_chrp_cpu_nr __initdata = 0;

/*
 * With CHRP SMP we need to use the OF to start the other
 * processors so we can't wait until smp_boot_cpus (the OF is
 * trashed by then) so we have to put the processors into
 * a holding pattern controlled by the kernel (not OF) before
 * we destroy the OF.
 *
 * This uses a chunk of high memory, puts some holding pattern
 * code there and sends the other processors off to there until
 * smp_boot_cpus tells them to do something.  We do that by using
 * physical address 0x0.  The holding pattern checks that address
 * until its cpu # is there, when it is that cpu jumps to
 * __secondary_start().  smp_boot_cpus() takes care of setting those
 * values.
 *
 * We also use physical address 0x4 here to tell when a cpu
 * is in its holding pattern code.
 *
 * -- Cort
 *
 * Note that we have to do this if we have more than one CPU,
 * even if this is a UP kernel.  Otherwise when we trash OF
 * the other CPUs will start executing some random instructions
 * and crash the system.  -- paulus
 */
static void __init
prom_hold_cpus(unsigned long mem)
{
	extern void __secondary_hold(void);
	unsigned long i;
	int cpu;
	phandle node;
	char type[16], *path;
	unsigned int reg;

	/*
	 * XXX: hack to make sure we're chrp, assume that if we're
	 *      chrp we have a device_type property -- Cort
	 */
	node = call_prom("finddevice", 1, 1, "/");
	if ((int)call_prom("getprop", 4, 1, node,
			   "device_type",type, sizeof(type)) <= 0)
		return;

	/* copy the holding pattern code to someplace safe (0) */
	/* the holding pattern is now within the first 0x100
	   bytes of the kernel image -- paulus */
	memcpy((void *)0, _stext, 0x100);
	flush_icache_range(0, 0x100);

	/* look for cpus */
	*(unsigned long *)(0x0) = 0;
	asm volatile("dcbf 0,%0": : "r" (0) : "memory");
	for (node = NULL; prom_next_node(&node); ) {
		type[0] = 0;
		call_prom("getprop", 4, 1, node, "device_type",
			  type, sizeof(type));
		if (strcmp(type, "cpu") != 0)
			continue;
		path = (char *) mem;
		memset(path, 0, 256);
		if ((int) call_prom("package-to-path", 3, 1,
				    node, path, 255) < 0)
			continue;
		reg = -1;
		call_prom("getprop", 4, 1, node, "reg", &reg, sizeof(reg));
		cpu = smp_chrp_cpu_nr++;
#ifdef CONFIG_SMP
		smp_hw_index[cpu] = reg;
#endif /* CONFIG_SMP */
		/* XXX: hack - don't start cpu 0, this cpu -- Cort */
		if (cpu == 0)
			continue;
		prom_print("starting cpu ");
		prom_print(path);
		*(ulong *)(0x4) = 0;
		call_prom("start-cpu", 3, 0, node,
			  (char *)__secondary_hold - _stext, cpu);
		prom_print("...");
		for ( i = 0 ; (i < 10000) && (*(ulong *)(0x4) == 0); i++ )
			;
		if (*(ulong *)(0x4) == cpu)
			prom_print("ok\n");
		else {
			prom_print("failed: ");
			prom_print_hex(*(ulong *)0x4);
			prom_print("\n");
		}
	}
}

static void __init
prom_instantiate_rtas(void)
{
	ihandle prom_rtas;
	unsigned int i;
	struct prom_args prom_args;

	prom_rtas = call_prom("finddevice", 1, 1, "/rtas");
	if (prom_rtas == (void *) -1)
		return;

	rtas_size = 0;
	call_prom("getprop", 4, 1, prom_rtas,
		  "rtas-size", &rtas_size, sizeof(rtas_size));
	prom_print("instantiating rtas");
	if (rtas_size == 0) {
		rtas_data = 0;
	} else {
		/*
		 * Ask OF for some space for RTAS.
		 * Actually OF has bugs so we just arbitrarily
		 * use memory at the 6MB point.
		 */
		rtas_data = 6 << 20;
		prom_print(" at ");
		prom_print_hex(rtas_data);
	}

	prom_rtas = call_prom("open", 1, 1, "/rtas");
	prom_print("...");
	prom_args.service = "call-method";
	prom_args.nargs = 3;
	prom_args.nret = 2;
	prom_args.args[0] = "instantiate-rtas";
	prom_args.args[1] = prom_rtas;
	prom_args.args[2] = (void *) rtas_data;
	prom(&prom_args);
	i = 0;
	if (prom_args.args[3] == 0)
		i = (unsigned int)prom_args.args[4];
	rtas_entry = i;
	if ((rtas_entry == -1) || (rtas_entry == 0))
		prom_print(" failed\n");
	else
		prom_print(" done\n");
}

/*
 * 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(int r3, int r4, prom_entry pp)
{
	unsigned long mem;
	ihandle prom_mmu;
	unsigned long offset = reloc_offset();
	int i, l;
	char *p, *d;
 	unsigned long phys;
	void *result[3];

 	/* Default */
 	phys = (unsigned long) &_stext;

	/* First get a handle for the stdout device */
	prom = pp;
	prom_chosen = call_prom("finddevice", 1, 1, "/chosen");
	if (prom_chosen == (void *)-1)
		prom_exit();
	if ((int) call_prom("getprop", 4, 1, prom_chosen,
			    "stdout", &prom_stdout,
			    sizeof(prom_stdout)) <= 0)
		prom_exit();

	/* Get the full OF pathname of the stdout device */
	mem = (unsigned long) klimit + offset;
	p = (char *) mem;
	memset(p, 0, 256);
	call_prom("instance-to-path", 3, 1, prom_stdout, p, 255);
	of_stdout_device = p;
	mem += strlen(p) + 1;

	/* Get the boot device and translate it to a full OF pathname. */
	p = (char *) mem;
	l = (int) call_prom("getprop", 4, 1, prom_chosen,
			    "bootpath", p, 1<<20);
	if (l > 0) {
		p[l] = 0;	/* should already be null-terminated */
		bootpath = PTRUNRELOC(p);
		mem += l + 1;
		d = (char *) mem;
		*d = 0;
		call_prom("canon", 3, 1, p, d, 1<<20);
		bootdevice = PTRUNRELOC(d);
		mem = ALIGNUL(mem + strlen(d) + 1);
	}

	prom_instantiate_rtas();

#ifdef CONFIG_POWER4
	/*
	 * Find out how much memory we have and allocate a
	 * suitably-sized hash table.
	 */
	prom_alloc_htab();
#endif
	mem = check_display(mem);

	prom_print("copying OF device tree...");
	mem = copy_device_tree(mem, mem + (1<<20));
	prom_print("done\n");

	prom_hold_cpus(mem);

	klimit = (char *) (mem - offset);

	/* If we are already running at 0xc0000000, we assume we were
	 * loaded by an OF bootloader which did set a BAT for us.
	 * This breaks OF translate so we force phys to be 0.
	 */
	if (offset == 0) {
		prom_print("(already at 0xc0000000) phys=0\n");
		phys = 0;
	} else if ((int) call_prom("getprop", 4, 1, prom_chosen, "mmu",
				 &prom_mmu, sizeof(prom_mmu)) <= 0) {
		prom_print(" no MMU found\n");
	} else if ((int)call_prom_ret("call-method", 4, 4, result, "translate",
				      prom_mmu, &_stext, 1) != 0) {
		prom_print(" (translate failed)\n");
	} else {
		/* We assume the phys. address size is 3 cells */
		phys = (unsigned long)result[2];
	}

	if (prom_disp_node != 0)
		setup_disp_fake_bi(prom_disp_node);

	/* Use quiesce call to get OF to shut down any devices it's using */
	prom_print("Calling quiesce ...\n");
	call_prom("quiesce", 0, 0);

	/* Relocate various pointers which will be used once the
	   kernel is running at the address it was linked at. */
	for (i = 0; i < prom_num_displays; ++i)
		prom_display_paths[i] = PTRUNRELOC(prom_display_paths[i]);

#ifdef CONFIG_SERIAL_CORE_CONSOLE
	/* Relocate the of stdout for console autodetection */
	of_stdout_device = PTRUNRELOC(of_stdout_device);
#endif

	prom_print("returning 0x");
	prom_print_hex(phys);
	prom_print("from prom_init\n");
	prom_stdout = NULL;

	return phys;
}

/*
 * early_get_property is used to access the device tree image prepared
 * by BootX very early on, before the pointers in it have been relocated.
 */
static void * __init
early_get_property(unsigned long base, unsigned long node, char *prop)
{
	struct device_node *np = (struct device_node *)(base + node);
	struct property *pp;

	for (pp = np->properties; pp != 0; pp = pp->next) {
		pp = (struct property *) (base + (unsigned long)pp);
		if (strcmp((char *)((unsigned long)pp->name + base),
			   prop) == 0) {
			return (void *)((unsigned long)pp->value + base);
		}
	}
	return NULL;
}

/* Is boot-info compatible ? */
#define BOOT_INFO_IS_COMPATIBLE(bi)		((bi)->compatible_version <= BOOT_INFO_VERSION)
#define BOOT_INFO_IS_V2_COMPATIBLE(bi)	((bi)->version >= 2)
#define BOOT_INFO_IS_V4_COMPATIBLE(bi)	((bi)->version >= 4)

void __init
bootx_init(unsigned long r4, unsigned long phys)
{
	boot_infos_t *bi = (boot_infos_t *) r4;
	unsigned long space;
	unsigned long ptr, x;
	char *model;

	boot_infos = PTRUNRELOC(bi);
	if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
		bi->logicalDisplayBase = NULL;

#ifdef CONFIG_BOOTX_TEXT
	btext_init(bi);

	/*
	 * Test if boot-info is compatible.  Done only in config
	 * CONFIG_BOOTX_TEXT since there is nothing much we can do
	 * with an incompatible version, except display a message
	 * and eventually hang the processor...
	 *
	 * I'll try to keep enough of boot-info compatible in the
	 * future to always allow display of this message;
	 */
	if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
		btext_drawstring(" !!! WARNING - Incompatible version of BootX !!!\n\n\n");
		btext_flushscreen();
	}
#endif	/* CONFIG_BOOTX_TEXT */

	/* New BootX enters kernel with MMU off, i/os are not allowed
	   here. This hack will have been done by the boostrap anyway.
	*/
	if (bi->version < 4) {
		/*
		 * XXX If this is an iMac, turn off the USB controller.
		 */
		model = (char *) early_get_property
			(r4 + bi->deviceTreeOffset, 4, "model");
		if (model
		    && (strcmp(model, "iMac,1") == 0
			|| strcmp(model, "PowerMac1,1") == 0)) {
			out_le32((unsigned *)0x80880008, 1);	/* XXX */
		}
	}

	/* Move klimit to enclose device tree, args, ramdisk, etc... */
	if (bi->version < 5) {
		space = bi->deviceTreeOffset + bi->deviceTreeSize;
		if (bi->ramDisk)
			space = bi->ramDisk + bi->ramDiskSize;
	} else
		space = bi->totalParamsSize;
	klimit = PTRUNRELOC((char *) bi + space);

	/* New BootX will have flushed all TLBs and enters kernel with
	   MMU switched OFF, so this should not be useful anymore.
	*/
	if (bi->version < 4) {
		/*
		 * Touch each page to make sure the PTEs for them
		 * are in the hash table - the aim is to try to avoid
		 * getting DSI exceptions while copying the kernel image.
		 */
		for (ptr = ((unsigned long) &_stext) & PAGE_MASK;
		     ptr < (unsigned long)bi + space; ptr += PAGE_SIZE)
			x = *(volatile unsigned long *)ptr;
	}

#ifdef CONFIG_BOOTX_TEXT
	/*
	 * Note that after we call btext_prepare_BAT, we can't do
	 * prom_draw*, flushscreen or clearscreen until we turn the MMU
	 * on, since btext_prepare_BAT sets disp_bi.logicalDisplayBase
	 * to a virtual address.
	 */
	btext_prepare_BAT();
#endif
}