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-rw-r--r--arch/c6x/kernel/module.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/c6x/kernel/module.c b/arch/c6x/kernel/module.c
new file mode 100644
index 00000000000..5fc03f18f56
--- /dev/null
+++ b/arch/c6x/kernel/module.c
@@ -0,0 +1,123 @@
+/*
+ * Port on Texas Instruments TMS320C6x architecture
+ *
+ * Copyright (C) 2005, 2009, 2010, 2011 Texas Instruments Incorporated
+ * Author: Thomas Charleux (thomas.charleux@jaluna.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/kernel.h>
+
+static inline int fixup_pcr(u32 *ip, Elf32_Addr dest, u32 maskbits, int shift)
+{
+ u32 opcode;
+ long ep = (long)ip & ~31;
+ long delta = ((long)dest - ep) >> 2;
+ long mask = (1 << maskbits) - 1;
+
+ if ((delta >> (maskbits - 1)) == 0 ||
+ (delta >> (maskbits - 1)) == -1) {
+ opcode = *ip;
+ opcode &= ~(mask << shift);
+ opcode |= ((delta & mask) << shift);
+ *ip = opcode;
+
+ pr_debug("REL PCR_S%d[%p] dest[%p] opcode[%08x]\n",
+ maskbits, ip, (void *)dest, opcode);
+
+ return 0;
+ }
+ pr_err("PCR_S%d reloc %p -> %p out of range!\n",
+ maskbits, ip, (void *)dest);
+
+ return -1;
+}
+
+/*
+ * apply a RELA relocation
+ */
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ Elf32_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+ Elf_Sym *sym;
+ u32 *location, opcode;
+ unsigned int i;
+ Elf32_Addr v;
+ Elf_Addr offset = 0;
+
+ pr_debug("Applying relocate section %u to %u with offset 0x%x\n",
+ relsec, sechdrs[relsec].sh_info, offset);
+
+ for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ /* This is where to make the change */
+ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ + rel[i].r_offset - offset;
+
+ /* This is the symbol it is referring to. Note that all
+ undefined symbols have been resolved. */
+ sym = (Elf_Sym *)sechdrs[symindex].sh_addr
+ + ELF32_R_SYM(rel[i].r_info);
+
+ /* this is the adjustment to be made */
+ v = sym->st_value + rel[i].r_addend;
+
+ switch (ELF32_R_TYPE(rel[i].r_info)) {
+ case R_C6000_ABS32:
+ pr_debug("RELA ABS32: [%p] = 0x%x\n", location, v);
+ *location = v;
+ break;
+ case R_C6000_ABS16:
+ pr_debug("RELA ABS16: [%p] = 0x%x\n", location, v);
+ *(u16 *)location = v;
+ break;
+ case R_C6000_ABS8:
+ pr_debug("RELA ABS8: [%p] = 0x%x\n", location, v);
+ *(u8 *)location = v;
+ break;
+ case R_C6000_ABS_L16:
+ opcode = *location;
+ opcode &= ~0x7fff80;
+ opcode |= ((v & 0xffff) << 7);
+ pr_debug("RELA ABS_L16[%p] v[0x%x] opcode[0x%x]\n",
+ location, v, opcode);
+ *location = opcode;
+ break;
+ case R_C6000_ABS_H16:
+ opcode = *location;
+ opcode &= ~0x7fff80;
+ opcode |= ((v >> 9) & 0x7fff80);
+ pr_debug("RELA ABS_H16[%p] v[0x%x] opcode[0x%x]\n",
+ location, v, opcode);
+ *location = opcode;
+ break;
+ case R_C6000_PCR_S21:
+ if (fixup_pcr(location, v, 21, 7))
+ return -ENOEXEC;
+ break;
+ case R_C6000_PCR_S12:
+ if (fixup_pcr(location, v, 12, 16))
+ return -ENOEXEC;
+ break;
+ case R_C6000_PCR_S10:
+ if (fixup_pcr(location, v, 10, 13))
+ return -ENOEXEC;
+ break;
+ default:
+ pr_err("module %s: Unknown RELA relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
+ }
+
+ return 0;
+}