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authorGuo Ren <ren_guo@c-sky.com>2018-09-05 14:25:16 +0800
committerGuo Ren <ren_guo@c-sky.com>2018-10-26 00:54:23 +0800
commit9d056df0924edbb0a30c85a1c1d3153c1229ec47 (patch)
tree08fb43ab68f67f5b5eb9d311f37a90e64b94d099 /arch/csky/kernel/module.c
parenta0ae62806ff495b60235cc4f2fee3f3ab6a265c9 (diff)
downloadlinux-sh-9d056df0924edbb0a30c85a1c1d3153c1229ec47.tar.gz
csky: ELF and module probe
This patch adds ELF definition and module relocate codes. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/csky/kernel/module.c')
-rw-r--r--arch/csky/kernel/module.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/csky/kernel/module.c b/arch/csky/kernel/module.c
new file mode 100644
index 000000000000..65abab0c7a47
--- /dev/null
+++ b/arch/csky/kernel/module.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <asm/pgtable.h>
+
+#if defined(__CSKYABIV2__)
+#define IS_BSR32(hi16, lo16) (((hi16) & 0xFC00) == 0xE000)
+#define IS_JSRI32(hi16, lo16) ((hi16) == 0xEAE0)
+
+#define CHANGE_JSRI_TO_LRW(addr) do { \
+ *(uint16_t *)(addr) = (*(uint16_t *)(addr) & 0xFF9F) | 0x001a; \
+ *((uint16_t *)(addr) + 1) = *((uint16_t *)(addr) + 1) & 0xFFFF; \
+} while (0)
+
+#define SET_JSR32_R26(addr) do { \
+ *(uint16_t *)(addr) = 0xE8Fa; \
+ *((uint16_t *)(addr) + 1) = 0x0000; \
+} while (0)
+#endif
+
+int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec, struct module *me)
+{
+ unsigned int i;
+ Elf32_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+ Elf32_Sym *sym;
+ uint32_t *location;
+ short *temp;
+#if defined(__CSKYABIV2__)
+ uint16_t *location_tmp;
+#endif
+
+ 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;
+ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+ + ELF32_R_SYM(rel[i].r_info);
+
+ switch (ELF32_R_TYPE(rel[i].r_info)) {
+ case R_CSKY_32:
+ /* We add the value into the location given */
+ *location = rel[i].r_addend + sym->st_value;
+ break;
+ case R_CSKY_PC32:
+ /* Add the value, subtract its postition */
+ *location = rel[i].r_addend + sym->st_value
+ - (uint32_t)location;
+ break;
+ case R_CSKY_PCRELJSR_IMM11BY2:
+ break;
+ case R_CSKY_PCRELJSR_IMM26BY2:
+#if defined(__CSKYABIV2__)
+ location_tmp = (uint16_t *)location;
+ if (IS_BSR32(*location_tmp, *(location_tmp + 1)))
+ break;
+
+ if (IS_JSRI32(*location_tmp, *(location_tmp + 1))) {
+ /* jsri 0x... --> lrw r26, 0x... */
+ CHANGE_JSRI_TO_LRW(location);
+ /* lsli r0, r0 --> jsr r26 */
+ SET_JSR32_R26(location + 1);
+ }
+#endif
+ break;
+ case R_CSKY_ADDR_HI16:
+ temp = ((short *)location) + 1;
+ *temp = (short)
+ ((rel[i].r_addend + sym->st_value) >> 16);
+ break;
+ case R_CSKY_ADDR_LO16:
+ temp = ((short *)location) + 1;
+ *temp = (short)
+ ((rel[i].r_addend + sym->st_value) & 0xffff);
+ break;
+ default:
+ pr_err("module %s: Unknown relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
+ }
+ return 0;
+}