android_kernel_xiaomi_sm8350/arch/ppc64/boot/addnote.c
Paul Mackerras 66faf9845a [PATCH] ppc64: tell firmware about kernel capabilities
On pSeries systems, according to the platform architecture specs, we are
supposed to be supplying a structure to firmware that tells firmware about
our capabilities, such as which version of the data structures that
describe available memory we are expecting to see.  The way we end up
having to supply this data structure is a bit gross, since it was designed
for AIX and doesn't suit us very well.  This patch adds the code to supply
this data structure to the firmware.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:45 -07:00

206 lines
5.0 KiB
C

/*
* Program to hack in a PT_NOTE program header entry in an ELF file.
* This is needed for OF on RS/6000s to load an image correctly.
* Note that OF needs a program header entry for the note, not an
* ELF section.
*
* Copyright 2000 Paul Mackerras.
*
* 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.
*
* Usage: addnote zImage
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
/* CHRP note section */
char arch[] = "PowerPC";
#define N_DESCR 6
unsigned int descr[N_DESCR] = {
0xffffffff, /* real-mode = true */
0x00c00000, /* real-base, i.e. where we expect OF to be */
0xffffffff, /* real-size */
0xffffffff, /* virt-base */
0xffffffff, /* virt-size */
0x4000, /* load-base */
};
/* RPA note section */
char rpaname[] = "IBM,RPA-Client-Config";
/*
* Note: setting ignore_my_client_config *should* mean that OF ignores
* all the other fields, but there is a firmware bug which means that
* it looks at the splpar field at least. So these values need to be
* reasonable.
*/
#define N_RPA_DESCR 8
unsigned int rpanote[N_RPA_DESCR] = {
0, /* lparaffinity */
64, /* min_rmo_size */
0, /* min_rmo_percent */
40, /* max_pft_size */
1, /* splpar */
-1, /* min_load */
0, /* new_mem_def */
1, /* ignore_my_client_config */
};
#define ROUNDUP(len) (((len) + 3) & ~3)
unsigned char buf[512];
#define GET_16BE(off) ((buf[off] << 8) + (buf[(off)+1]))
#define GET_32BE(off) ((GET_16BE(off) << 16) + GET_16BE((off)+2))
#define PUT_16BE(off, v) (buf[off] = ((v) >> 8) & 0xff, \
buf[(off) + 1] = (v) & 0xff)
#define PUT_32BE(off, v) (PUT_16BE((off), (v) >> 16), \
PUT_16BE((off) + 2, (v)))
/* Structure of an ELF file */
#define E_IDENT 0 /* ELF header */
#define E_PHOFF 28
#define E_PHENTSIZE 42
#define E_PHNUM 44
#define E_HSIZE 52 /* size of ELF header */
#define EI_MAGIC 0 /* offsets in E_IDENT area */
#define EI_CLASS 4
#define EI_DATA 5
#define PH_TYPE 0 /* ELF program header */
#define PH_OFFSET 4
#define PH_FILESZ 16
#define PH_HSIZE 32 /* size of program header */
#define PT_NOTE 4 /* Program header type = note */
#define ELFCLASS32 1
#define ELFDATA2MSB 2
unsigned char elf_magic[4] = { 0x7f, 'E', 'L', 'F' };
int
main(int ac, char **av)
{
int fd, n, i;
int ph, ps, np;
int nnote, nnote2, ns;
if (ac != 2) {
fprintf(stderr, "Usage: %s elf-file\n", av[0]);
exit(1);
}
fd = open(av[1], O_RDWR);
if (fd < 0) {
perror(av[1]);
exit(1);
}
nnote = 12 + ROUNDUP(strlen(arch) + 1) + sizeof(descr);
nnote2 = 12 + ROUNDUP(strlen(rpaname) + 1) + sizeof(rpanote);
n = read(fd, buf, sizeof(buf));
if (n < 0) {
perror("read");
exit(1);
}
if (n < E_HSIZE || memcmp(&buf[E_IDENT+EI_MAGIC], elf_magic, 4) != 0)
goto notelf;
if (buf[E_IDENT+EI_CLASS] != ELFCLASS32
|| buf[E_IDENT+EI_DATA] != ELFDATA2MSB) {
fprintf(stderr, "%s is not a big-endian 32-bit ELF image\n",
av[1]);
exit(1);
}
ph = GET_32BE(E_PHOFF);
ps = GET_16BE(E_PHENTSIZE);
np = GET_16BE(E_PHNUM);
if (ph < E_HSIZE || ps < PH_HSIZE || np < 1)
goto notelf;
if (ph + (np + 2) * ps + nnote + nnote2 > n)
goto nospace;
for (i = 0; i < np; ++i) {
if (GET_32BE(ph + PH_TYPE) == PT_NOTE) {
fprintf(stderr, "%s already has a note entry\n",
av[1]);
exit(0);
}
ph += ps;
}
/* XXX check that the area we want to use is all zeroes */
for (i = 0; i < 2 * ps + nnote + nnote2; ++i)
if (buf[ph + i] != 0)
goto nospace;
/* fill in the program header entry */
ns = ph + 2 * ps;
PUT_32BE(ph + PH_TYPE, PT_NOTE);
PUT_32BE(ph + PH_OFFSET, ns);
PUT_32BE(ph + PH_FILESZ, nnote);
/* fill in the note area we point to */
/* XXX we should probably make this a proper section */
PUT_32BE(ns, strlen(arch) + 1);
PUT_32BE(ns + 4, N_DESCR * 4);
PUT_32BE(ns + 8, 0x1275);
strcpy(&buf[ns + 12], arch);
ns += 12 + strlen(arch) + 1;
for (i = 0; i < N_DESCR; ++i, ns += 4)
PUT_32BE(ns, descr[i]);
/* fill in the second program header entry and the RPA note area */
ph += ps;
PUT_32BE(ph + PH_TYPE, PT_NOTE);
PUT_32BE(ph + PH_OFFSET, ns);
PUT_32BE(ph + PH_FILESZ, nnote2);
/* fill in the note area we point to */
PUT_32BE(ns, strlen(rpaname) + 1);
PUT_32BE(ns + 4, sizeof(rpanote));
PUT_32BE(ns + 8, 0x12759999);
strcpy(&buf[ns + 12], rpaname);
ns += 12 + ROUNDUP(strlen(rpaname) + 1);
for (i = 0; i < N_RPA_DESCR; ++i, ns += 4)
PUT_32BE(ns, rpanote[i]);
/* Update the number of program headers */
PUT_16BE(E_PHNUM, np + 2);
/* write back */
lseek(fd, (long) 0, SEEK_SET);
i = write(fd, buf, n);
if (i < 0) {
perror("write");
exit(1);
}
if (i < n) {
fprintf(stderr, "%s: write truncated\n", av[1]);
exit(1);
}
exit(0);
notelf:
fprintf(stderr, "%s does not appear to be an ELF file\n", av[1]);
exit(1);
nospace:
fprintf(stderr, "sorry, I can't find space in %s to put the note\n",
av[1]);
exit(1);
}