* Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> [100817 18:33]: > On Tue, Aug 17, 2010 at 05:12:11PM +0300, Tony Lindgren wrote: > > Great, will give it a try hopefully tomorrow. Sounds like that's the way > > to deal with fixing up things when booting up older UP ARMv6 without the > > 32v6 support :) > > What I've also been debating about is adding another word to the > smpalt structure, that being a set of flags which denote the situation > where the alternative should be used. > > That means we can use it to do individual word replacements for SMP vs > UP, ARMv6 vs ARMv6k etc. Sounds good to me. Maybe it should then be called cpualt instead of smpalt? Tried booting your patch and needed the following fix for Cortex-A8 UP. Now it boots to the following error: Machine configuration botched (nr -1073741824), unable to continue. Does some struct size need to be changed or something? Regards, Tony
From: Tony Lindgren <tony@xxxxxxxxxxx> Date: Thu, 19 Aug 2010 10:22:23 +0300 Subject: [PATCH] Fix smp_on_up detection This is needed to detect UP properly on older ARMv7 like Cortex-A8. Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -346,8 +346,10 @@ __fixup_smp: bne smp_on_up @ no, assume UP mrc p15, 0, r0, c0, c0, 5 @ read MIDR movs r0, r0, lsr #30 - teqne r0, #3 @ check top two bits 00 or 11 - moveq pc, lr + teq r0, #0 @ check two top bits 00 + beq smp_on_up @ yes, assume UP + teq r0, #3 @ check top two bits 11 + movne pc, lr @ no, running on SMP hw smp_on_up: adr r0, 1f
