powerpc/module64: Use symbolic instructions names.

To increase readability/maintainability, replace hard coded
instructions values by symbolic names.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fix R_PPC64_ENTRY case, the addi reads from r2 not r12]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2019-05-03 06:40:17 +00:00 committed by Michael Ellerman
parent 4eb4516ead
commit a2b6f26c26

View File

@ -133,20 +133,27 @@ struct ppc64_stub_entry
* the stub, but it's significantly shorter to put these values at the
* end of the stub code, and patch the stub address (32-bits relative
* to the TOC ptr, r2) into the stub.
*
* addis r11,r2, <high>
* addi r11,r11, <low>
* std r2,R2_STACK_OFFSET(r1)
* ld r12,32(r11)
* ld r2,40(r11)
* mtctr r12
* bctr
*/
static u32 ppc64_stub_insns[] = {
0x3d620000, /* addis r11,r2, <high> */
0x396b0000, /* addi r11,r11, <low> */
PPC_INST_ADDIS | __PPC_RT(R11) | __PPC_RA(R2),
PPC_INST_ADDI | __PPC_RT(R11) | __PPC_RA(R11),
/* Save current r2 value in magic place on the stack. */
0xf8410000|R2_STACK_OFFSET, /* std r2,R2_STACK_OFFSET(r1) */
0xe98b0020, /* ld r12,32(r11) */
PPC_INST_STD | __PPC_RS(R2) | __PPC_RA(R1) | R2_STACK_OFFSET,
PPC_INST_LD | __PPC_RT(R12) | __PPC_RA(R11) | 32,
#ifdef PPC64_ELF_ABI_v1
/* Set up new r2 from function descriptor */
0xe84b0028, /* ld r2,40(r11) */
PPC_INST_LD | __PPC_RT(R2) | __PPC_RA(R11) | 40,
#endif
0x7d8903a6, /* mtctr r12 */
0x4e800420 /* bctr */
PPC_INST_MTCTR | __PPC_RS(R12),
PPC_INST_BCTR,
};
#ifdef CONFIG_DYNAMIC_FTRACE
@ -704,18 +711,21 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
* ld r2, ...(r12)
* add r2, r2, r12
*/
if ((((uint32_t *)location)[0] & ~0xfffc)
!= 0xe84c0000)
if ((((uint32_t *)location)[0] & ~0xfffc) !=
(PPC_INST_LD | __PPC_RT(R2) | __PPC_RA(R12)))
break;
if (((uint32_t *)location)[1] != 0x7c426214)
if (((uint32_t *)location)[1] !=
(PPC_INST_ADD | __PPC_RT(R2) | __PPC_RA(R2) | __PPC_RB(R12)))
break;
/*
* If found, replace it with:
* addis r2, r12, (.TOC.-func)@ha
* addi r2, r2, (.TOC.-func)@l
*/
((uint32_t *)location)[0] = 0x3c4c0000 + PPC_HA(value);
((uint32_t *)location)[1] = 0x38420000 + PPC_LO(value);
((uint32_t *)location)[0] = PPC_INST_ADDIS | __PPC_RT(R2) |
__PPC_RA(R12) | PPC_HA(value);
((uint32_t *)location)[1] = PPC_INST_ADDI | __PPC_RT(R2) |
__PPC_RA(R2) | PPC_LO(value);
break;
case R_PPC64_REL16_HA:
@ -769,12 +779,19 @@ static unsigned long create_ftrace_stub(const Elf64_Shdr *sechdrs,
{
struct ppc64_stub_entry *entry;
unsigned int i, num_stubs;
/*
* ld r12,PACATOC(r13)
* addis r12,r12,<high>
* addi r12,r12,<low>
* mtctr r12
* bctr
*/
static u32 stub_insns[] = {
0xe98d0000 | PACATOC, /* ld r12,PACATOC(r13) */
0x3d8c0000, /* addis r12,r12,<high> */
0x398c0000, /* addi r12,r12,<low> */
0x7d8903a6, /* mtctr r12 */
0x4e800420, /* bctr */
PPC_INST_LD | __PPC_RT(R12) | __PPC_RA(R13) | PACATOC,
PPC_INST_ADDIS | __PPC_RT(R12) | __PPC_RA(R12),
PPC_INST_ADDI | __PPC_RT(R12) | __PPC_RA(R12),
PPC_INST_MTCTR | __PPC_RS(R12),
PPC_INST_BCTR,
};
long reladdr;