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authorPaul Gortmaker <paul.gortmaker@gmail.com>2009-05-07 11:18:40 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2009-05-07 12:21:01 -0400
commitae51e609843f7d0aaeb1c2ad9f89d252a4899885 (patch)
treeaf632106715c1c3db9c974fdecf6903e86eef1ed /arch/arm/kernel
parenta029b706d3b2d3a139bdeae84131d9a0f35f6478 (diff)
[ARM] 5507/1: support R_ARM_MOVW_ABS_NC and MOVT_ABS relocation types
From: Bruce Ashfield <bruce.ashfield@windriver.com> To fully support the armv7-a instruction set/optimizations, support for the R_ARM_MOVW_ABS_NC and R_ARM_MOVT_ABS relocation types is required. The MOVW and MOVT are both load-immediate instructions, MOVW loads 16 bits into the bottom half of a register, and MOVT loads 16 bits into the top half of a register. The relocation information for these instructions has a full 32 bit value, plus an addend which is stored in the 16 immediate bits in the instruction itself. The immediate bits in the instruction are not contiguous (the register # splits it into a 4 bit and 12 bit value), so the addend has to be extracted accordingly and added to the value. The value is then split and put into the instruction; a MOVW uses the bottom 16 bits of the value, and a MOVT uses the top 16 bits. Signed-off-by: David Borman <david.borman@windriver.com> Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r--arch/arm/kernel/module.c15
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index d1731e39b496..bac03c81489d 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -169,6 +169,21 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
169 *(u32 *)loc = offset & 0x7fffffff; 169 *(u32 *)loc = offset & 0x7fffffff;
170 break; 170 break;
171 171
172 case R_ARM_MOVW_ABS_NC:
173 case R_ARM_MOVT_ABS:
174 offset = *(u32 *)loc;
175 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
176 offset = (offset ^ 0x8000) - 0x8000;
177
178 offset += sym->st_value;
179 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
180 offset >>= 16;
181
182 *(u32 *)loc &= 0xfff0f000;
183 *(u32 *)loc |= ((offset & 0xf000) << 4) |
184 (offset & 0x0fff);
185 break;
186
172 default: 187 default:
173 printk(KERN_ERR "%s: unknown relocation: %u\n", 188 printk(KERN_ERR "%s: unknown relocation: %u\n",
174 module->name, ELF32_R_TYPE(rel->r_info)); 189 module->name, ELF32_R_TYPE(rel->r_info));