linux/arch/powerpc/kernel/cpu_setup_ppc970.S, branch v3.0.30

powerpc: Use LOAD_REG_IMMEDIATE only for constants on 64-bit

2008-09-15T18:08:35Z

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

[POWERPC] powerpc: Enable DEEPNAP power savings mode on 970MP

2006-10-16T06:32:25Z

Without this patch, on an idle system I get: cpu-power-0:21.638 cpu-power-1:27.102 cpu-power-2:29.343 cpu-power-3:25.784 Total: 103.8W With this patch: cpu-power-0:11.730 cpu-power-1:17.185 cpu-power-2:18.547 cpu-power-3:17.528 Total: 65.0W If I lower HZ to 100, I can get it as low as: cpu-power-0:10.938 cpu-power-1:16.021 cpu-power-2:17.245 cpu-power-3:16.145 Total: 60.2W Another (older) Quad G5 went from 54W to 39W at HZ=250. Coming back out of Deep Nap takes 40-70 cycles longer than coming back from just Nap (which already takes quite a while). I don't think it'll be a performance issue (interrupt latency on an idle system), but in case someone does measurements feel free to report them. Signed-off-by: Olof Johansson Acked-by: Michael Buesch Signed-off-by: Paul Mackerras

Merge branch 'merge'

2006-08-25T04:56:07Z

[POWERPC] Cleanup CPU inits

2006-08-25T03:27:35Z

Cleanup CPU inits a bit more, Geoff Levand already did some earlier. * Move CPU state save to cpu_setup, since cpu_setup is only ever done on cpu 0 on 64-bit and save is never done more than once. * Rename __restore_cpu_setup to __restore_cpu_ppc970 and add function pointers to the cputable to use instead. Powermac always has 970 so no need to check there. * Rename __970_cpu_preinit to __cpu_preinit_ppc970 and check PVR before calling it instead of in it, it's too early to use cputable. * Rename pSeries_secondary_smp_init to generic_secondary_smp_init since everyone but powermac and iSeries use it. Signed-off-by: Olof Johansson Signed-off-by: Paul Mackerras

[POWERPC] Rename cpu_setup_power4.S to cpu_setup_ppc970.S

2006-08-25T03:27:35Z

Rename cpu_setup_power4.S to cpu_setup_ppc970.S, since that's really what it is. No functional or other changes. Signed-off-by: Olof Johansson Signed-off-by: Paul Mackerras