/* bootinfo */
#define BOOTINFO_VERSION 1
#define NODEV (-1) /* non-existent device */
#define PAGE_SHIFT 12 /* LOG2(PAGE_SIZE) */
#define PAGE_SIZE (1<<PAGE_SHIFT) /* bytes/page */
#define PAGE_MASK (PAGE_SIZE-1)
#define N_BIOS_GEOM 8
struct bootinfo {
unsigned int bi_version;
const unsigned char *bi_kernelname;
struct nfs_diskless *bi_nfs_diskless;
/* End of fields that are always present. */
#define bi_endcommon bi_n_bios_used
unsigned int bi_n_bios_used;
unsigned long bi_bios_geom[N_BIOS_GEOM];
unsigned int bi_size;
unsigned char bi_memsizes_valid;
unsigned char bi_pad[3];
unsigned long bi_basemem;
unsigned long bi_extmem;
unsigned long bi_symtab;
unsigned long bi_esymtab;
/* Note that these are in the FreeBSD headers but were not here... */
unsigned long bi_kernend; /* end of kernel space */
unsigned long bi_envp; /* environment */
unsigned long bi_modulep; /* preloaded modules */
};
static struct bootinfo bsdinfo;
#ifdef ELF_IMAGE
static Elf32_Shdr *shdr; /* To support the FreeBSD kludge! */
static Address symtab_load;
static Address symstr_load;
static int symtabindex;
static int symstrindex;
#endif
static enum {
Unknown, Tagged, Aout, Elf, Aout_FreeBSD, Elf_FreeBSD,
} image_type = Unknown;
static unsigned int off;
#ifdef ELF_IMAGE
static void elf_freebsd_probe(void)
{
image_type = Elf;
if ( (estate.e.elf32.e_entry & 0xf0000000) &&
(estate.e.elf32.e_type == ET_EXEC))
{
image_type = Elf_FreeBSD;
printf("/FreeBSD");
off = -(estate.e.elf32.e_entry & 0xff000000);
estate.e.elf32.e_entry += off;
}
/* Make sure we have a null to start with... */
shdr = 0;
/* Clear the symbol index values... */
symtabindex = -1;
symstrindex = -1;
/* ...and the load addresses of the symbols */
symtab_load = 0;
symstr_load = 0;
}
static void elf_freebsd_fixup_segment(void)
{
if (image_type == Elf_FreeBSD) {
estate.p.phdr32[estate.segment].p_paddr += off;
}
}
static void elf_freebsd_find_segment_end(void)
{
/* Count the bytes read even for the last block
* as we will need to know where the last block
* ends in order to load the symbols correctly.
* (plus it could be useful elsewhere...)
* Note that we need to count the actual size,
* not just the end of the disk image size.
*/
estate.curaddr +=
(estate.p.phdr32[estate.segment].p_memsz -
estate.p.phdr32[estate.segment].p_filesz);
}
static int elf_freebsd_debug_loader(unsigned int offset)
{
/* No more segments to be loaded - time to start the
* nasty state machine to support the loading of
* FreeBSD debug symbols due to the fact that FreeBSD
* uses/exports the kernel's debug symbols in order
* to make much of the system work! Amazing (arg!)
*
* We depend on the fact that for the FreeBSD kernel,
* there is only one section of debug symbols and that
* the section is after all of the loaded sections in
* the file. This assumes a lot but is somewhat required
* to make this code not be too annoying. (Where do you
* load symbols when the code has not loaded yet?)
* Since this function is actually just a callback from
* the network data transfer code, we need to be able to
* work with the data as it comes in. There is no chance
* for doing a seek other than forwards.
*
* The process we use is to first load the section
* headers. Once they are loaded (shdr != 0) we then
* look for where the symbol table and symbol table
* strings are and setup some state that we found
* them and fall into processing the first one (which
* is the symbol table) and after that has been loaded,
* we try the symbol strings. Note that the order is
* actually required as the memory image depends on
* the symbol strings being loaded starting at the
* end of the symbol table. The kernel assumes this
* layout of the image.
*
* At any point, if we get to the end of the load file
* or the section requested is earlier in the file than
* the current file pointer, we just end up falling
* out of this and booting the kernel without this
* information.
*/
/* Make sure that the next address is long aligned... */
/* Assumes size of long is a power of 2... */
estate.curaddr = (estate.curaddr + sizeof(long) - 1) & ~(sizeof(long) - 1);
/* If we have not yet gotten the shdr loaded, try that */
if (shdr == 0)
{
estate.toread = estate.e.elf32.e_shnum * estate.e.elf32.e_shentsize;
estate.skip = estate.e.elf32.e_shoff - (estate.loc + offset);
if (estate.toread)
{
#if ELF_DEBUG
printf("shdr *, size %lX, curaddr %lX\n",
estate.toread, estate.curaddr);
#endif
/* Start reading at the curaddr and make that the shdr */
shdr = (Elf32_Shdr *)phys_to_virt(estate.curaddr);
/* Start to read... */
return 1;
}
}
else
{
/* We have the shdr loaded, check if we have found
* the indexs where the symbols are supposed to be */
if ((symtabindex == -1) && (symstrindex == -1))
{
int i;
/* Make sure that the address is page aligned... */
/* Symbols need to start in their own page(s)... */
estate.curaddr = (estate.curaddr + 4095) & ~4095;
/* Need to make new indexes... */
for (i=0; i < estate.e.elf32.e_shnum; i++)
{
if (shdr[i].sh_type == SHT_SYMTAB)
{
int j;
for (j=0; j < estate.e.elf32.e_phnum; j++)
{
/* Check only for loaded sections */
if ((estate.p.phdr32[j].p_type | 0x80) == (PT_LOAD | 0x80))
{
/* Only the extra symbols */
if ((shdr[i].sh_offset >= estate.p.phdr32[j].p_offset) &&
((shdr[i].sh_offset + shdr[i].sh_size) <=
(estate.p.phdr32[j].p_offset + estate.p.phdr32[j].p_filesz)))
{
shdr[i].sh_offset=0;
shdr[i].sh_size=0;
break;
}
}
}
if ((shdr[i].sh_offset != 0) && (shdr[i].sh_size != 0))
{
symtabindex = i;
symstrindex = shdr[i].sh_link;
}
}
}
}
/* Check if we have a symbol table index and have not loaded it */
if ((symtab_load == 0) && (symtabindex >= 0))
{
/* No symbol table yet? Load it first... */
/* This happens to work out in a strange way.
* If we are past the point in the file already,
* we will skip a *large* number of bytes which
* ends up bringing us to the end of the file and
* an old (default) boot. Less code and lets
* the state machine work in a cleaner way but this
* is a nasty side-effect trick... */
estate.skip = shdr[symtabindex].sh_offset - (estate.loc + offset);
/* And we need to read this many bytes... */
estate.toread = shdr[symtabindex].sh_size;
if (estate.toread)
{
#if ELF_DEBUG
printf("db sym, size %lX, curaddr %lX\n",
estate.toread, estate.curaddr);
#endif
/* Save where we are loading this... */
symtab_load = phys_to_virt(estate.curaddr);
*((long *)phys_to_virt(estate.curaddr)) = estate.toread;
estate.curaddr += sizeof(long);
/* Start to read... */
return 1;
}
}
else if ((symstr_load == 0) && (symstrindex >= 0))
{
/* We have already loaded the symbol table, so
* now on to the symbol strings... */
/* Same nasty trick as above... */
estate.skip = shdr[symstrindex].sh_offset - (estate.loc + offset);
/* And we need to read this many bytes... */
estate.toread = shdr[symstrindex].sh_size;
if (estate.toread)
{
#if ELF_DEBUG
printf("db str, size %lX, curaddr %lX\n",
estate.toread, estate.curaddr);
#endif
/* Save where we are loading this... */
symstr_load = phys_to_virt(estate.curaddr);
*((long *)phys_to_virt(estate.curaddr)) = estate.toread;
estate.curaddr += sizeof(long);
/* Start to read... */
return 1;
}
}
}
/* all done */
return 0;
}
static void elf_freebsd_boot(unsigned long entry)
{
if (image_type != Elf_FreeBSD)
return;
memset(&bsdinfo, 0, sizeof(bsdinfo));
bsdinfo.bi_basemem = meminfo.basememsize;
bsdinfo.bi_extmem = meminfo.memsize;
bsdinfo.bi_memsizes_valid = 1;
bsdinfo.bi_version = BOOTINFO_VERSION;
bsdinfo.bi_kernelname = virt_to_phys(KERNEL_BUF);
bsdinfo.bi_nfs_diskless = NULL;
bsdinfo.bi_size = sizeof(bsdinfo);
#define RB_BOOTINFO 0x80000000 /* have `struct bootinfo *' arg */
if(freebsd_kernel_env[0] != '\0'){
freebsd_howto |= RB_BOOTINFO;
bsdinfo.bi_envp = (unsigned long)freebsd_kernel_env;
}
/* Check if we have symbols loaded, and if so,
* made the meta_data needed to pass those to
* the kernel. */
if ((symtab_load !=0) && (symstr_load != 0))
{
unsigned long *t;
bsdinfo.bi_symtab = symtab_load;
/* End of symbols (long aligned...) */
/* Assumes size of long is a power of 2... */
bsdinfo.bi_esymtab = (symstr_load +
sizeof(long) +
*((long *)symstr_load) +
sizeof(long) - 1) & ~(sizeof(long) - 1);
/* Where we will build the meta data... */
t = phys_to_virt(bsdinfo.bi_esymtab);
#if ELF_DEBUG
printf("Metadata at %lX\n",t);
#endif
/* Set up the pointer to the memory... */
bsdinfo.bi_modulep = virt_to_phys(t);
/* The metadata structure is an array of 32-bit
* words where we store some information about the
* system. This is critical, as FreeBSD now looks
* only for the metadata for the extended symbol
* information rather than in the bootinfo.
*/
/* First, do the kernel name and the kernel type */
/* Note that this assumed x86 byte order... */
/* 'kernel\0\0' */
*t++=MODINFO_NAME; *t++= 7; *t++=0x6E72656B; *t++=0x00006C65;
/* 'elf kernel\0\0' */
*t++=MODINFO_TYPE; *t++=11; *t++=0x20666C65; *t++=0x6E72656B; *t++ = 0x00006C65;
/* Now the symbol start/end - note that they are
* here in local/physical address - the Kernel
* boot process will relocate the addresses. */
*t++=MODINFOMD_SSYM | MODINFO_METADATA; *t++=sizeof(*t); *t++=bsdinfo.bi_symtab;
*t++=MODINFOMD_ESYM | MODINFO_METADATA; *t++=sizeof(*t); *t++=bsdinfo.bi_esymtab;
*t++=MODINFO_END; *t++=0; /* end of metadata */
/* Since we have symbols we need to make
* sure that the kernel knows its own end
* of memory... It is not _end but after
* the symbols and the metadata... */
bsdinfo.bi_kernend = virt_to_phys(t);
/* Signal locore.s that we have a valid bootinfo
* structure that was completely filled in. */
freebsd_howto |= 0x80000000;
}
xstart32(entry, freebsd_howto, NODEV, 0, 0, 0,
virt_to_phys(&bsdinfo), 0, 0, 0);
longjmp(restart_etherboot, -2);
}
#endif
#ifdef AOUT_IMAGE
static void aout_freebsd_probe(void)
{
image_type = Aout;
if (((astate.head.a_midmag >> 16) & 0xffff) == 0) {
/* Some other a.out variants have a different
* value, and use other alignments (e.g. 1K),
* not the 4K used by FreeBSD. */
image_type = Aout_FreeBSD;
printf("/FreeBSD");
off = -(astate.head.a_entry & 0xff000000);
astate.head.a_entry += off;
}
}
static void aout_freebsd_boot(void)
{
if (image_type == Aout_FreeBSD) {
memset(&bsdinfo, 0, sizeof(bsdinfo));
bsdinfo.bi_basemem = meminfo.basememsize;
bsdinfo.bi_extmem = meminfo.memsize;
bsdinfo.bi_memsizes_valid = 1;
bsdinfo.bi_version = BOOTINFO_VERSION;
bsdinfo.bi_kernelname = virt_to_phys(KERNEL_BUF);
bsdinfo.bi_nfs_diskless = NULL;
bsdinfo.bi_size = sizeof(bsdinfo);
xstart32(astate.head.a_entry, freebsd_howto, NODEV, 0, 0, 0,
virt_to_phys(&bsdinfo), 0, 0, 0);
longjmp(restart_etherboot, -2);
}
}
#endif
