From e31aa453bbc4886a7bd33e5c2afa526d6f55bd7a Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Sat, 30 Aug 2008 11:41:12 +1000 Subject: powerpc: Use LOAD_REG_IMMEDIATE only for constants on 64-bit Using LOAD_REG_IMMEDIATE to get the address of kernel symbols generates 5 instructions where LOAD_REG_ADDR can do it in one, and will generate R_PPC64_ADDR16_* relocations in the output when we get to making the kernel as a position-independent executable, which we'd rather not have to handle. This changes various bits of assembly code to use LOAD_REG_ADDR when we need to get the address of a symbol, or to use suitable position-independent code for cases where we can't access the TOC for various reasons, or if we're not running at the address we were linked at. It also cleans up a few minor things; there's no reason to save and restore SRR0/1 around RTAS calls, __mmu_off can get the return address from LR more conveniently than the caller can supply it in R4 (and we already assume elsewhere that EA == RA if the MMU is on in early boot), and enable_64b_mode was using 5 instructions where 2 would do. Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/cpu_setup_ppc970.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/kernel/cpu_setup_ppc970.S') diff --git a/arch/powerpc/kernel/cpu_setup_ppc970.S b/arch/powerpc/kernel/cpu_setup_ppc970.S index bf118c3..27f2507 100644 --- a/arch/powerpc/kernel/cpu_setup_ppc970.S +++ b/arch/powerpc/kernel/cpu_setup_ppc970.S @@ -110,7 +110,7 @@ load_hids: isync /* Save away cpu state */ - LOAD_REG_IMMEDIATE(r5,cpu_state_storage) + LOAD_REG_ADDR(r5,cpu_state_storage) /* Save HID0,1,4 and 5 */ mfspr r3,SPRN_HID0 @@ -134,7 +134,7 @@ _GLOBAL(__restore_cpu_ppc970) rldicl. r0,r0,4,63 beqlr - LOAD_REG_IMMEDIATE(r5,cpu_state_storage) + LOAD_REG_ADDR(r5,cpu_state_storage) /* Before accessing memory, we make sure rm_ci is clear */ li r0,0 mfspr r3,SPRN_HID4 -- cgit v1.1