sparc: fix tftpboot.img for sparc64 on little-endian host
piggyback_32 adapted to support sparc64:
- locating "HdrS" differs for sparc and sparc64
- sparc64 updates a_text, a_data + a_bss in the final a.out header
Updated Makefile to use piggyback_32 for sparc64.
Deleted the now unused piggyback_64.c
piggyback_32.c is host endian neutral and works on both
little-endian and big-endian hosts.
This fixes a long standing bug where sparc64 could not
generate tftpboot.img on a x86 host.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/boot/piggyback_32.c b/arch/sparc/boot/piggyback_32.c
index c4b0843..d56e9de 100644
--- a/arch/sparc/boot/piggyback_32.c
+++ b/arch/sparc/boot/piggyback_32.c
@@ -107,7 +107,8 @@
*
* Return 0 if either start or end is not found
*/
-static int get_start_end(const char *filename, unsigned int *start, unsigned int *end)
+static int get_start_end(const char *filename, unsigned int *start,
+ unsigned int *end)
{
FILE *map;
char buffer[1024];
@@ -131,11 +132,60 @@
return 1;
}
+#define LOOKBACK (128 * 4)
+#define BUFSIZE 1024
+/*
+ * Find the HdrS entry from head_32/head_64.
+ * We check if it is at the beginning of the file (sparc64 case)
+ * and if not we search for it.
+ * When we search do so in steps of 4 as HdrS is on a 4-byte aligned
+ * address (it is on same alignment as sparc instructions)
+ * Return the offset to the HdrS entry (as off_t)
+ */
+static off_t get_hdrs_offset(int kernelfd, const char *filename)
+{
+ char buffer[BUFSIZE];
+ off_t offset;
+ int i;
+
+ if (lseek(kernelfd, 0, SEEK_SET) < 0)
+ die("lseek");
+ if (read(kernelfd, buffer, BUFSIZE) != BUFSIZE)
+ die(filename);
+
+ if (buffer[40] == 'H' && buffer[41] == 'd' &&
+ buffer[42] == 'r' && buffer[43] == 'S') {
+ return 40;
+ } else {
+ /* Find the gokernel label */
+ /* Decode offset from branch instruction */
+ offset = ld2(buffer + AOUT_TEXT_OFFSET + 2) << 2;
+ /* Go back 512 bytes so we do not miss HdrS */
+ offset -= LOOKBACK;
+ /* skip a.out header */
+ offset += AOUT_TEXT_OFFSET;
+ if (lseek(kernelfd, offset, SEEK_SET) < 0)
+ die("lseek");
+ if (read(kernelfd, buffer, BUFSIZE) != BUFSIZE)
+ die(filename);
+
+ for (i = 0; i < LOOKBACK; i += 4) {
+ if (buffer[i + 0] == 'H' && buffer[i + 1] == 'd' &&
+ buffer[i + 2] == 'r' && buffer[i + 3] == 'S') {
+ return offset + i;
+ }
+ }
+ }
+ fprintf (stderr, "Couldn't find headers signature in %s\n", filename);
+ exit(1);
+}
+
int main(int argc,char **argv)
{
static char aout_magic[] = { 0x01, 0x03, 0x01, 0x07 };
- char buffer[1024], *q, *r;
- unsigned int i, start, end, offset;
+ char buffer[1024];
+ unsigned int i, start, end;
+ off_t offset;
struct stat s;
int image, tail;
@@ -147,7 +197,8 @@
die(argv[4]);
if (!get_start_end(argv[3], &start, &end)) {
- fprintf (stderr, "Could not determine start and end from %s\n", argv[3]);
+ fprintf(stderr, "Could not determine start and end from %s\n",
+ argv[3]);
exit(1);
}
if ((image = open(argv[2], O_RDWR)) < 0)
@@ -159,27 +210,17 @@
exit(1);
}
/*
- * We need to fill in values for sparc_ramdisk_image + sparc_ramdisk_size
+ * We need to fill in values for
+ * sparc_ramdisk_image + sparc_ramdisk_size
* To locate these symbols search for the "HdrS" text which appear
* in the image a little before the gokernel symbol.
* See definition of these in init_32.S
*/
- /* Find the gokernel label */
- i = AOUT_TEXT_OFFSET + (ld2(buffer + AOUT_TEXT_OFFSET + 2) << 2) - 512;
- if (lseek(image, i, 0) < 0)
- die("lseek");
- if (read(image, buffer, 1024) != 1024)
- die(argv[2]);
- for (q = buffer, r = q + 512; q < r; q += 4) {
- if (*q == 'H' && q[1] == 'd' && q[2] == 'r' && q[3] == 'S')
- break;
- }
- if (q == r) {
- fprintf (stderr, "Couldn't find headers signature in the kernel.\n");
- exit(1);
- }
- offset = i + (q - buffer) + 10;
+ offset = get_hdrs_offset(image, argv[2]);
+ /* skip HdrS + LINUX_VERSION_CODE + HdrS version */
+ offset += 10;
+
if (lseek(image, offset, 0) < 0)
die("lseek");
@@ -198,6 +239,22 @@
if (write(image, buffer + 2, 14) != 14)
die(argv[2]);
+ /* For sparc64 update a_text and clear a_data + a_bss */
+ if (is64bit)
+ {
+ if (lseek(image, 4, 0) < 0)
+ die("lseek");
+ /* a_text */
+ st4(buffer, align(end + 32 + 8191) - (start & ~0x3fffffUL) +
+ s.st_size);
+ /* a_data */
+ st4(buffer + 4, 0);
+ /* a_bss */
+ st4(buffer + 8, 0);
+ if (write(image, buffer, 12) != 12)
+ die(argv[2]);
+ }
+
/* seek page aligned boundary in the image file and add boot image */
if (lseek(image, AOUT_TEXT_OFFSET - start + align(end + 32), 0) < 0)
die("lseek");