kernel.git/arch/powerpc/kernel/head_64.S, branch linux-2.6.18.y

[POWERPC] force 64bit mode in fwnmi handlers to workaround firmware bugs

2006-07-28T18:07:08Z

The firmware of POWER4 and JS20 systems does not switch the cpu to 64bit mode when the registered system_reset and machine_check handlers get called. If a 32bit process runs on that cpu at the time of the event, the cpu remains in 32bit mode. xmon and kdump can not deal with it, the result is an error like 'Bad kernel stack pointer fff2aad0 at 3200'. xmon just loses some register info, but booting the kdump kernel usually fails. Both handlers are not hot paths. Duplicate the EXCEPTION_PROLOG_PSERIES macro and add two instructions to switch to 64bit: li r11,5; rldimi r10,r11,61,0; Signed-off-by: Olaf Hering Signed-off-by: Paul Mackerras

Remove obsolete #include

2006-06-30T17:25:36Z

Signed-off-by: Jörn Engel Signed-off-by: Adrian Bunk

[POWERPC] Make sure smp_processor_id works very early in boot

2006-06-29T06:22:47Z

There's a small period early in boot where we don't know which cpu we're running on. That's ok, except that it means we have no paca, or more correctly that our paca pointer points somewhere random. So that we can safely call things like smp_processor_id(), we need a paca, so just assume we're on cpu 0. No code should _write_ to the paca before we've set the correct one up. We setup the proper paca after we've scanned the flat device tree in early_setup(), so there's no need to do it again in start_here_common. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras

[POWERPC] Skip the "copy down" of the kernel if it is already at zero.

2006-06-28T05:18:53Z

This patch allows the kernel to recognized that it was loaded at zero and the copy down of the image is unnecessary. This is useful for Simulators and kexec models. On a typical 3.8 MiB vmlinux.strip this saves about 2.3 million instructions. Signed-off-by: Paul Mackerras

[POWERPC] Setup the boot cpu's paca pointer in C rather than asm

2006-06-28T01:59:47Z

There's no need to set the boot cpu paca in asm, so do it in C so us mere mortals can understand it. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras

[POWERPC] Remove remaining iSeries debugger cruft

2006-06-28T01:59:46Z

None of this seems to be necessary, so let's see if can remove it and not break anything. Booted on iSeries & pSeries here. NB. we don't remove the hvReleaseData, we just move it down so that the file reads more clearly. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras

[POWERPC] cell: add RAS support

2006-06-21T05:01:29Z

This is a first version of support for the Cell BE "Reliability, Availability and Serviceability" features. It doesn't yet handle some of the RAS interrupts (the ones described in iic_is/iic_irr), I'm still working on a proper way to expose these. They are essentially a cascaded controller by themselves (sic !) though I may just handle them locally to the iic driver. I need also to sync with David Erb on the way he hooked in the performance monitor interrupt. So that's all for 2.6.17 and I'll do more work on that with my rework of the powerpc interrupt layer that I'm hacking on at the moment. Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras

powerpc: Use correct sequence for putting CPU into nap mode

2006-04-18T11:49:11Z

We weren't using the recommended sequence for putting the CPU into nap mode. When I changed the idle loop, for some reason 7447A cpus started hanging when we put them into nap mode. Changing to the recommended sequence fixes that. The complexity here is that the recommended sequence is a loop that keeps putting the cpu back into nap mode. Clearly we need some way to break out of the loop when an interrupt (external interrupt, decrementer, performance monitor) occurs. Here we use a bit in the thread_info struct to indicate that we need this, and the exception entry code notices this and arranges for the exception to return to the value in the link register, thus breaking out of the loop. We use a new `local_flags' field in the thread_info which we can alter without needing to use an atomic update sequence. The PPC970 has the same recommended sequence, so we do the same thing there too. This also fixes a bug in the kernel stack overflow handling code on 32-bit, since it was causing a value that we needed in a register to get trashed. Signed-off-by: Paul Mackerras

[PATCH] powerpc: Allow non zero boot cpuids

2006-03-27T03:48:48Z

We currently have a hack to flip the boot cpu and its secondary thread to logical cpuid 0 and 1. This means the logical - physical mapping will differ depending on which cpu is boot cpu. This is most apparent on kexec, where we might kexec on any cpu and therefore change the mapping from boot to boot. The patch below does a first pass early on to work out the logical cpuid of the boot thread. We then fix up some paca structures to match. Ive also removed the boot_cpuid_phys variable for ppc64, to be consistent we use get_hard_smp_processor_id(boot_cpuid) everywhere. Signed-off-by: Anton Blanchard Signed-off-by: Paul Mackerras

[PATCH] correct the comment about stackpointer alignment in __boot_from_prom

2006-03-27T03:48:32Z

The address of variable val in prom_init_stdout is passed to prom_getprop. prom_getprop casts the pointer to u32 and passes it to call_prom in the hope that OpenFirmware stores something there. But the pointer is truncated in the lower bits and the expected value is stored somewhere else. In my testing I had a stackpointer of 0x0023e6b4. val was at offset 120, wich has address 0x0023e72c. But the value passed to OF was 0x0023e728. c00000000040b710: 3b 01 00 78 addi r24,r1,120 ... c00000000040b754: 57 08 00 38 rlwinm r8,r24,0,0,28 ... c00000000040b784: 80 01 00 78 lwz r0,120(r1) ... c00000000040b798: 90 1b 00 0c stw r0,12(r27) ... The stackpointer came from 32bit code. The chain was yaboot -> zImage -> vmlinux PowerMac OpenFirmware does appearently not handle the ELF sections correctly. If yaboot was compiled in /usr/src/packages/BUILD/lilo-10.1.1/yaboot, then the stackpointer is unaligned. But the stackpointer is correct if yaboot is compiled in /tmp/yaboot. This bug triggered since 2.6.15, now prom_getprop is an inline function. gcc clears the lower bits, instead of just clearing the upper 32 bits. Signed-off-by: Olaf Hering Signed-off-by: Paul Mackerras