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-rw-r--r--arch/powerpc/boot/addRamDisk.c311
1 files changed, 311 insertions, 0 deletions
diff --git a/arch/powerpc/boot/addRamDisk.c b/arch/powerpc/boot/addRamDisk.c
new file mode 100644
index 000000000000..c02a99952be7
--- /dev/null
+++ b/arch/powerpc/boot/addRamDisk.c
@@ -0,0 +1,311 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <elf.h>
+
+#define ElfHeaderSize (64 * 1024)
+#define ElfPages (ElfHeaderSize / 4096)
+#define KERNELBASE (0xc000000000000000)
+#define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
+
+struct addr_range {
+ unsigned long long addr;
+ unsigned long memsize;
+ unsigned long offset;
+};
+
+static int check_elf64(void *p, int size, struct addr_range *r)
+{
+ Elf64_Ehdr *elf64 = p;
+ Elf64_Phdr *elf64ph;
+
+ if (elf64->e_ident[EI_MAG0] != ELFMAG0 ||
+ elf64->e_ident[EI_MAG1] != ELFMAG1 ||
+ elf64->e_ident[EI_MAG2] != ELFMAG2 ||
+ elf64->e_ident[EI_MAG3] != ELFMAG3 ||
+ elf64->e_ident[EI_CLASS] != ELFCLASS64 ||
+ elf64->e_ident[EI_DATA] != ELFDATA2MSB ||
+ elf64->e_type != ET_EXEC || elf64->e_machine != EM_PPC64)
+ return 0;
+
+ if ((elf64->e_phoff + sizeof(Elf64_Phdr)) > size)
+ return 0;
+
+ elf64ph = (Elf64_Phdr *) ((unsigned long)elf64 +
+ (unsigned long)elf64->e_phoff);
+
+ r->memsize = (unsigned long)elf64ph->p_memsz;
+ r->offset = (unsigned long)elf64ph->p_offset;
+ r->addr = (unsigned long long)elf64ph->p_vaddr;
+
+#ifdef DEBUG
+ printf("PPC64 ELF file, ph:\n");
+ printf("p_type 0x%08x\n", elf64ph->p_type);
+ printf("p_flags 0x%08x\n", elf64ph->p_flags);
+ printf("p_offset 0x%016llx\n", elf64ph->p_offset);
+ printf("p_vaddr 0x%016llx\n", elf64ph->p_vaddr);
+ printf("p_paddr 0x%016llx\n", elf64ph->p_paddr);
+ printf("p_filesz 0x%016llx\n", elf64ph->p_filesz);
+ printf("p_memsz 0x%016llx\n", elf64ph->p_memsz);
+ printf("p_align 0x%016llx\n", elf64ph->p_align);
+ printf("... skipping 0x%08lx bytes of ELF header\n",
+ (unsigned long)elf64ph->p_offset);
+#endif
+
+ return 64;
+}
+void get4k(FILE *file, char *buf )
+{
+ unsigned j;
+ unsigned num = fread(buf, 1, 4096, file);
+ for ( j=num; j<4096; ++j )
+ buf[j] = 0;
+}
+
+void put4k(FILE *file, char *buf )
+{
+ fwrite(buf, 1, 4096, file);
+}
+
+void death(const char *msg, FILE *fdesc, const char *fname)
+{
+ fprintf(stderr, msg);
+ fclose(fdesc);
+ unlink(fname);
+ exit(1);
+}
+
+int main(int argc, char **argv)
+{
+ char inbuf[4096];
+ struct addr_range vmlinux;
+ FILE *ramDisk;
+ FILE *inputVmlinux;
+ FILE *outputVmlinux;
+
+ char *rd_name, *lx_name, *out_name;
+
+ size_t i;
+ unsigned long ramFileLen;
+ unsigned long ramLen;
+ unsigned long roundR;
+ unsigned long offset_end;
+
+ unsigned long kernelLen;
+ unsigned long actualKernelLen;
+ unsigned long round;
+ unsigned long roundedKernelLen;
+ unsigned long ramStartOffs;
+ unsigned long ramPages;
+ unsigned long roundedKernelPages;
+ unsigned long hvReleaseData;
+ u_int32_t eyeCatcher = 0xc8a5d9c4;
+ unsigned long naca;
+ unsigned long xRamDisk;
+ unsigned long xRamDiskSize;
+ long padPages;
+
+
+ if (argc < 2) {
+ fprintf(stderr, "Name of RAM disk file missing.\n");
+ exit(1);
+ }
+ rd_name = argv[1];
+
+ if (argc < 3) {
+ fprintf(stderr, "Name of vmlinux file missing.\n");
+ exit(1);
+ }
+ lx_name = argv[2];
+
+ if (argc < 4) {
+ fprintf(stderr, "Name of vmlinux output file missing.\n");
+ exit(1);
+ }
+ out_name = argv[3];
+
+
+ ramDisk = fopen(rd_name, "r");
+ if ( ! ramDisk ) {
+ fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", rd_name);
+ exit(1);
+ }
+
+ inputVmlinux = fopen(lx_name, "r");
+ if ( ! inputVmlinux ) {
+ fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", lx_name);
+ exit(1);
+ }
+
+ outputVmlinux = fopen(out_name, "w+");
+ if ( ! outputVmlinux ) {
+ fprintf(stderr, "output vmlinux file \"%s\" failed to open.\n", out_name);
+ exit(1);
+ }
+
+ i = fread(inbuf, 1, sizeof(inbuf), inputVmlinux);
+ if (i != sizeof(inbuf)) {
+ fprintf(stderr, "can not read vmlinux file %s: %u\n", lx_name, i);
+ exit(1);
+ }
+
+ i = check_elf64(inbuf, sizeof(inbuf), &vmlinux);
+ if (i == 0) {
+ fprintf(stderr, "You must have a linux kernel specified as argv[2]\n");
+ exit(1);
+ }
+
+ /* Input Vmlinux file */
+ fseek(inputVmlinux, 0, SEEK_END);
+ kernelLen = ftell(inputVmlinux);
+ fseek(inputVmlinux, 0, SEEK_SET);
+ printf("kernel file size = %lu\n", kernelLen);
+
+ actualKernelLen = kernelLen - ElfHeaderSize;
+
+ printf("actual kernel length (minus ELF header) = %lu\n", actualKernelLen);
+
+ round = actualKernelLen % 4096;
+ roundedKernelLen = actualKernelLen;
+ if ( round )
+ roundedKernelLen += (4096 - round);
+ printf("Vmlinux length rounded up to a 4k multiple = %ld/0x%lx \n", roundedKernelLen, roundedKernelLen);
+ roundedKernelPages = roundedKernelLen / 4096;
+ printf("Vmlinux pages to copy = %ld/0x%lx \n", roundedKernelPages, roundedKernelPages);
+
+ offset_end = _ALIGN_UP(vmlinux.memsize, 4096);
+ /* calc how many pages we need to insert between the vmlinux and the start of the ram disk */
+ padPages = offset_end/4096 - roundedKernelPages;
+
+ /* Check and see if the vmlinux is already larger than _end in System.map */
+ if (padPages < 0) {
+ /* vmlinux is larger than _end - adjust the offset to the start of the embedded ram disk */
+ offset_end = roundedKernelLen;
+ printf("vmlinux is larger than _end indicates it needs to be - offset_end = %lx \n", offset_end);
+ padPages = 0;
+ printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
+ }
+ else {
+ /* _end is larger than vmlinux - use the offset to _end that we calculated from the system map */
+ printf("vmlinux is smaller than _end indicates is needed - offset_end = %lx \n", offset_end);
+ printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
+ }
+
+
+
+ /* Input Ram Disk file */
+ // Set the offset that the ram disk will be started at.
+ ramStartOffs = offset_end; /* determined from the input vmlinux file and the system map */
+ printf("Ram Disk will start at offset = 0x%lx \n", ramStartOffs);
+
+ fseek(ramDisk, 0, SEEK_END);
+ ramFileLen = ftell(ramDisk);
+ fseek(ramDisk, 0, SEEK_SET);
+ printf("%s file size = %ld/0x%lx \n", rd_name, ramFileLen, ramFileLen);
+
+ ramLen = ramFileLen;
+
+ roundR = 4096 - (ramLen % 4096);
+ if ( roundR ) {
+ printf("Rounding RAM disk file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
+ ramLen += roundR;
+ }
+
+ printf("Rounded RAM disk size is %ld/0x%lx \n", ramLen, ramLen);
+ ramPages = ramLen / 4096;
+ printf("RAM disk pages to copy = %ld/0x%lx\n", ramPages, ramPages);
+
+
+
+ // Copy 64K ELF header
+ for (i=0; i<(ElfPages); ++i) {
+ get4k( inputVmlinux, inbuf );
+ put4k( outputVmlinux, inbuf );
+ }
+
+ /* Copy the vmlinux (as full pages). */
+ fseek(inputVmlinux, ElfHeaderSize, SEEK_SET);
+ for ( i=0; i<roundedKernelPages; ++i ) {
+ get4k( inputVmlinux, inbuf );
+ put4k( outputVmlinux, inbuf );
+ }
+
+ /* Insert pad pages (if appropriate) that are needed between */
+ /* | the end of the vmlinux and the ram disk. */
+ for (i=0; i<padPages; ++i) {
+ memset(inbuf, 0, 4096);
+ put4k(outputVmlinux, inbuf);
+ }
+
+ /* Copy the ram disk (as full pages). */
+ for ( i=0; i<ramPages; ++i ) {
+ get4k( ramDisk, inbuf );
+ put4k( outputVmlinux, inbuf );
+ }
+
+ /* Close the input files */
+ fclose(ramDisk);
+ fclose(inputVmlinux);
+ /* And flush the written output file */
+ fflush(outputVmlinux);
+
+
+
+ /* Fixup the new vmlinux to contain the ram disk starting offset (xRamDisk) and the ram disk size (xRamDiskSize) */
+ /* fseek to the hvReleaseData pointer */
+ fseek(outputVmlinux, ElfHeaderSize + 0x24, SEEK_SET);
+ if (fread(&hvReleaseData, 4, 1, outputVmlinux) != 1) {
+ death("Could not read hvReleaseData pointer\n", outputVmlinux, out_name);
+ }
+ hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */
+ printf("hvReleaseData is at %08lx\n", hvReleaseData);
+
+ /* fseek to the hvReleaseData */
+ fseek(outputVmlinux, ElfHeaderSize + hvReleaseData, SEEK_SET);
+ if (fread(inbuf, 0x40, 1, outputVmlinux) != 1) {
+ death("Could not read hvReleaseData\n", outputVmlinux, out_name);
+ }
+ /* Check hvReleaseData sanity */
+ if (memcmp(inbuf, &eyeCatcher, 4) != 0) {
+ death("hvReleaseData is invalid\n", outputVmlinux, out_name);
+ }
+ /* Get the naca pointer */
+ naca = ntohl(*((u_int32_t*) &inbuf[0x0C])) - KERNELBASE;
+ printf("Naca is at offset 0x%lx \n", naca);
+
+ /* fseek to the naca */
+ fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
+ if (fread(inbuf, 0x18, 1, outputVmlinux) != 1) {
+ death("Could not read naca\n", outputVmlinux, out_name);
+ }
+ xRamDisk = ntohl(*((u_int32_t *) &inbuf[0x0c]));
+ xRamDiskSize = ntohl(*((u_int32_t *) &inbuf[0x14]));
+ /* Make sure a RAM disk isn't already present */
+ if ((xRamDisk != 0) || (xRamDiskSize != 0)) {
+ death("RAM disk is already attached to this kernel\n", outputVmlinux, out_name);
+ }
+ /* Fill in the values */
+ *((u_int32_t *) &inbuf[0x0c]) = htonl(ramStartOffs);
+ *((u_int32_t *) &inbuf[0x14]) = htonl(ramPages);
+
+ /* Write out the new naca */
+ fflush(outputVmlinux);
+ fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
+ if (fwrite(inbuf, 0x18, 1, outputVmlinux) != 1) {
+ death("Could not write naca\n", outputVmlinux, out_name);
+ }
+ printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08lx\n",
+ ramPages, ramStartOffs);
+
+ /* Done */
+ fclose(outputVmlinux);
+ /* Set permission to executable */
+ chmod(out_name, S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
+
+ return 0;
+}
+
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