summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/entry_32.S
Commit message (Collapse)AuthorAgeFilesLines
* powerpc: Use correct sequence for putting CPU into nap modePaul Mackerras2006-04-181-18/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | 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 <paulus@samba.org>
* powerpc: Unify the 32 and 64 bit idle loopsPaul Mackerras2006-03-271-2/+6
| | | | | | | | | | This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle loops. It brings over the concept of having a ppc_md.power_save function from 32-bit to ARCH=powerpc, which lets us get rid of native_idle(). With this we will also be able to simplify the idle handling for pSeries and cell. Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Fix various syscall/signal/swapcontext bugsPaul Mackerras2006-03-081-71/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] TIF_RESTORE_SIGMASK support for arch/powerpcDavid Woodhouse2006-01-181-4/+4
| | | | | | | | | | | Implement the TIF_RESTORE_SIGMASK flag in the new arch/powerpc kernel, for both 32-bit and 64-bit system call paths. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] powerpc: Cleanup LOADADDR etc. asm macrosDavid Gibson2006-01-131-1/+1
| | | | | | | | | | | | | | | | | | This patch consolidates the variety of macros used for loading 32 or 64-bit constants in assembler (LOADADDR, LOADBASE, SET_REG_TO_*). The idea is to make the set of macros consistent across 32 and 64 bit and to make it more obvious which is the appropriate one to use in a given situation. The new macros and their semantics are described in the comments in ppc_asm.h. In the process, we change several places that were unnecessarily using immediate loads on ppc64 to use the GOT/TOC. Likewise we cleanup a couple of places where we were clumsily subtracting PAGE_OFFSET with asm instructions to use assemble-time arithmetic or the toreal() macro instead. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] Fix code that saves NVGPRS in 32-bit signal frameDavid Woodhouse2006-01-091-3/+3
| | | | | | | | | | | | | | On Thu, 2005-11-24 at 12:51 +0000, David Woodhouse wrote: > Somehow this one slipped through the cracks; when we ended up in > do_signal() on a 32-bit kernel but without having the caller-saved > registers into the regs, we didn't set the TIF_SAVE_NVGPRS flag to > ensure they got saved later. Oh, and if we actually set the flag, then we fairly quickly find out that I was a bit overzealous in copying code from entry_64.S ... :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] syscall entry/exit revampDavid Woodhouse2006-01-091-71/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Rename asm offset TRAP to _TRAP for 32-bitPaul Mackerras2005-10-281-22/+22
| | | | | | ... for consistency with 64-bit. Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Merge rtas.c into arch/powerpc/kernelPaul Mackerras2005-10-261-7/+5
| | | | | | | | | | | | | This splits arch/ppc64/kernel/rtas.c into arch/powerpc/kernel/rtas.c, which contains generic RTAS functions useful on any CHRP platform, and arch/powerpc/platforms/pseries/rtas-fw.[ch], which contain some pSeries-specific firmware flashing bits. The parts of rtas.c that are to do with pSeries-specific error logging are protected by a new CONFIG_RTAS_ERROR_LOGGING symbol. The inclusion of rtas.o is controlled by the CONFIG_PPC_RTAS symbol, and the relevant platforms select that. Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] powerpc: Merge thread_info.hDavid Gibson2005-10-211-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge ppc32 and ppc64 versions of thread_info.h. They were pretty similar already, the chief changes are: - Instead of inline asm to implement current_thread_info(), which needs to be different for ppc32 and ppc64, we use C with an asm("r1") register variable. gcc turns it into the same asm as we used to have for both platforms. - We replace ppc32's 'local_flags' with the ppc64 'syscall_noerror' field. The noerror flag was in fact the only thing in the local_flags field anyway, so the ppc64 approach is simpler, and means we only need a load-immediate/store instead of load/mask/store when clearing the flag. - In readiness for 64k pages, when THREAD_SIZE will be less than a page, ppc64 used kmalloc() rather than get_free_pages() to allocate the kernel stack. With this patch we do the same for ppc32, since there's no strong reason not to. - For ppc64, we no longer export THREAD_SHIFT and THREAD_SIZE via asm-offsets, thread_info.h can now be safely included in asm, as on ppc32. Built and booted on G4 Powerbook (ARCH=ppc and ARCH=powerpc) and Power5 (ARCH=ppc64 and ARCH=powerpc). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Fix a branch-too-far link error for 32-bit targetsPaul Mackerras2005-10-201-1/+2
| | | | Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.SPaul Mackerras2005-10-101-0/+1002
The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>