bootx_init.c

linux内核源码

/*
 *  Early boot support code for BootX bootloader
 *
 *  Copyright (C) 2005 Ben. Herrenschmidt ([e-mail])
 *
 *  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 <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/utsrelease.h>
#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/page.h>
#include <asm/bootx.h>
#include <asm/btext.h>
#include <asm/io.h>

#undef DEBUG
#define SET_BOOT_BAT

#ifdef DEBUG
#define DBG(fmt...) do { bootx_printf(fmt); } while(0)
#else
#define DBG(fmt...) do { } while(0)
#endif

extern void __start(unsigned long r3, unsigned long r4, unsigned long r5);

static unsigned long __initdata bootx_dt_strbase;
static unsigned long __initdata bootx_dt_strend;
static unsigned long __initdata bootx_node_chosen;
static boot_infos_t * __initdata bootx_info;
static char __initdata bootx_disp_path[256];

/* 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)

#ifdef CONFIG_BOOTX_TEXT
static void __init bootx_printf(const char *format, ...)
{
	const char *p, *q, *s;
	va_list args;
	unsigned long v;

	va_start(args, format);
	for (p = format; *p != 0; p = q) {
		for (q = p; *q != 0 && *q != '\n' && *q != '%'; ++q)
			;
		if (q > p)
			btext_drawtext(p, q - p);
		if (*q == 0)
			break;
		if (*q == '\n') {
			++q;
			btext_flushline();
			btext_drawstring("\r\n");
			btext_flushline();
			continue;
		}
		++q;
		if (*q == 0)
			break;
		switch (*q) {
		case 's':
			++q;
			s = va_arg(args, const char *);
			if (s == NULL)
				s = "<NULL>";
			btext_drawstring(s);
			break;
		case 'x':
			++q;
			v = va_arg(args, unsigned long);
			btext_drawhex(v);
			break;
		}
	}
}
#else /* CONFIG_BOOTX_TEXT */
static void __init bootx_printf(const char *format, ...) {}
#endif /* CONFIG_BOOTX_TEXT */

static void * __init bootx_early_getprop(unsigned long base,
					 unsigned long node,
					 char *prop)
{
	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
	u32 *ppp = &np->properties;

	while(*ppp) {
		struct bootx_dt_prop *pp =
			(struct bootx_dt_prop *)(base + *ppp);

		if (strcmp((char *)((unsigned long)pp->name + base),
			   prop) == 0) {
			return (void *)((unsigned long)pp->value + base);
		}
		ppp = &pp->next;
	}
	return NULL;
}

#define dt_push_token(token, mem) \
	do { \
		*(mem) = _ALIGN_UP(*(mem),4); \
		*((u32 *)*(mem)) = token; \
		*(mem) += 4; \
	} while(0)

static unsigned long __init bootx_dt_find_string(char *str)
{
	char *s, *os;

	s = os = (char *)bootx_dt_strbase;
	s += 4;
	while (s <  (char *)bootx_dt_strend) {
		if (strcmp(s, str) == 0)
			return s - os;
		s += strlen(s) + 1;
	}
	return 0;
}

static void __init bootx_dt_add_prop(char *name, void *data, int size,
				  unsigned long *mem_end)
{
	unsigned long soff = bootx_dt_find_string(name);
	if (data == NULL)
		size = 0;
	if (soff == 0) {
		bootx_printf("WARNING: Can't find string index for <%s>\n",
			     name);
		return;
	}
	if (size > 0x20000) {
		bootx_printf("WARNING: ignoring large property ");
		bootx_printf("%s length 0x%x\n", name, size);
		return;
	}
	dt_push_token(OF_DT_PROP, mem_end);
	dt_push_token(size, mem_end);
	dt_push_token(soff, mem_end);

	/* push property content */
	if (size && data) {
		memcpy((void *)*mem_end, data, size);
		*mem_end = _ALIGN_UP(*mem_end + size, 4);
	}
}

static void __init bootx_add_chosen_props(unsigned long base,
					  unsigned long *mem_end)
{
	u32 val;

	bootx_dt_add_prop("linux,bootx", NULL, 0, mem_end);

	if (bootx_info->kernelParamsOffset) {
		char *args = (char *)((unsigned long)bootx_info) +
			bootx_info->kernelParamsOffset;
		bootx_dt_add_prop("bootargs", args, strlen(args) + 1, mem_end);
	}
	if (bootx_info->ramDisk) {
		val = ((unsigned long)bootx_info) + bootx_info->ramDisk;
		bootx_dt_add_prop("linux,initrd-start", &val, 4, mem_end);
		val += bootx_info->ramDiskSize;
		bootx_dt_add_prop("linux,initrd-end", &val, 4, mem_end);
	}
	if (strlen(bootx_disp_path))
		bootx_dt_add_prop("linux,stdout-path", bootx_disp_path,
				  strlen(bootx_disp_path) + 1, mem_end);
}

static void __init bootx_add_display_props(unsigned long base,
					   unsigned long *mem_end,
					   int has_real_node)
{
	boot_infos_t *bi = bootx_info;
	u32 tmp;

	if (has_real_node) {
		bootx_dt_add_prop("linux,boot-display", NULL, 0, mem_end);
		bootx_dt_add_prop("linux,opened", NULL, 0, mem_end);
	} else
		bootx_dt_add_prop("linux,bootx-noscreen", NULL, 0, mem_end);

	tmp = bi->dispDeviceDepth;
	bootx_dt_add_prop("linux,bootx-depth", &tmp, 4, mem_end);
	tmp = bi->dispDeviceRect[2] - bi->dispDeviceRect[0];
	bootx_dt_add_prop("linux,bootx-width", &tmp, 4, mem_end);
	tmp = bi->dispDeviceRect[3] - bi->dispDeviceRect[1];
	bootx_dt_add_prop("linux,bootx-height", &tmp, 4, mem_end);
	tmp = bi->dispDeviceRowBytes;
	bootx_dt_add_prop("linux,bootx-linebytes", &tmp, 4, mem_end);
	tmp = (u32)bi->dispDeviceBase;
	if (tmp == 0)
		tmp = (u32)bi->logicalDisplayBase;
	tmp += bi->dispDeviceRect[1] * bi->dispDeviceRowBytes;
	tmp += bi->dispDeviceRect[0] * ((bi->dispDeviceDepth + 7) / 8);
	bootx_dt_add_prop("linux,bootx-addr", &tmp, 4, mem_end);
}

static void __init bootx_dt_add_string(char *s, unsigned long *mem_end)
{
	unsigned int l = strlen(s) + 1;
	memcpy((void *)*mem_end, s, l);
	bootx_dt_strend = *mem_end = *mem_end + l;
}

static void __init bootx_scan_dt_build_strings(unsigned long base,
					       unsigned long node,
					       unsigned long *mem_end)
{
	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
	u32 *cpp, *ppp = &np->properties;
	unsigned long soff;
	char *namep;

	/* Keep refs to known nodes */
	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
       	if (namep == NULL) {
		bootx_printf("Node without a full name !\n");
		namep = "";
	}
	DBG("* strings: %s\n", namep);

	if (!strcmp(namep, "/chosen")) {
		DBG(" detected /chosen ! adding properties names !\n");
		bootx_dt_add_string("linux,bootx", mem_end);
		bootx_dt_add_string("linux,stdout-path", mem_end);
		bootx_dt_add_string("linux,initrd-start", mem_end);
		bootx_dt_add_string("linux,initrd-end", mem_end);
		bootx_dt_add_string("bootargs", mem_end);
		bootx_node_chosen = node;
	}
	if (node == bootx_info->dispDeviceRegEntryOffset) {
		DBG(" detected display ! adding properties names !\n");
		bootx_dt_add_string("linux,boot-display", mem_end);
		bootx_dt_add_string("linux,opened", mem_end);
		strncpy(bootx_disp_path, namep, 255);
	}

	/* get and store all property names */
	while (*ppp) {
		struct bootx_dt_prop *pp =
			(struct bootx_dt_prop *)(base + *ppp);

		namep = pp->name ? (char *)(base + pp->name) : NULL;
 		if (namep == NULL || strcmp(namep, "name") == 0)
 			goto next;
		/* get/create string entry */
		soff = bootx_dt_find_string(namep);
		if (soff == 0)
			bootx_dt_add_string(namep, mem_end);
	next:
		ppp = &pp->next;
	}

	/* do all our children */
	cpp = &np->child;
	while(*cpp) {
		np = (struct bootx_dt_node *)(base + *cpp);
		bootx_scan_dt_build_strings(base, *cpp, mem_end);
		cpp = &np->sibling;
	}
}

static void __init bootx_scan_dt_build_struct(unsigned long base,
					      unsigned long node,
					      unsigned long *mem_end)
{
	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
	u32 *cpp, *ppp = &np->properties;
	char *namep, *p, *ep, *lp;
	int l;

	dt_push_token(OF_DT_BEGIN_NODE, mem_end);

	/* get the node's full name */
	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
	if (namep == NULL)
		namep = "";
	l = strlen(namep);

	DBG("* struct: %s\n", namep);

	/* Fixup an Apple bug where they have bogus \0 chars in the
	 * middle of the path in some properties, and extract
	 * the unit name (everything after the last '/').
	 */