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path: root/arch/powerpc/kernel/entry_32.S
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2008-06-26powerpc/85xx: add DOZE/NAP support for e500 coreKumar Gala
The e500 core enter DOZE/NAP power-saving modes when the core go to cpu_idle routine. The power management default running mode is DOZE, If the user echo 1 > /proc/sys/kernel/powersave-nap the system will change to NAP running mode. Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-06-02[POWERPC] 40x/Book-E: Save/restore volatile exception registersKumar Gala
On machines with more than one exception level any system register that might be modified by the "normal" exception level needs to be saved and restored on taking a higher level exception. We already are saving and restoring ESR and DEAR. For critical level add SRR0/1. For debug level add CSRR0/1 and SRR0/1. For machine check level add DSRR0/1, CSRR0/1, and SRR0/1. On FSL Book-E parts we always save/restore the MAS registers for critical, debug, and machine check level exceptions. On 44x we always save/restore the MMUCR. Additionally, we save and restore the ksp_limit since we have to adjust it for each exception level. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org>
2008-06-02[POWERPC] Rework EXC_LEVEL_EXCEPTION_PROLOG codeKumar Gala
* Cleanup the code a bit my allocating an INT_FRAME on our exception stack there by make references go from GPR11-INT_FRAME_SIZE(r8) to just GPR11(r8) * simplify {lvl}_transfer_to_handler code by moving the copying of the temp registers we use if we come from user space into the PROLOG * If the exception came from kernel mode copy thread_info flags, preempt, and task pointer from the process thread_info. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org>
2008-05-16[POWERPC] Defer processing of interrupts when the CPU wakes from sleep modePaul Mackerras
This provides a way to defer processing of an interrupt that wakes the processor out of sleep mode. On 32-bit platforms that use an interrupt to wake the processor, we have to have interrupts enabled in hardware at the point where we go to sleep, otherwise the processor will never wake up. However, because interrupts are logically disabled at this point, we don't want to process the interrupt straight away. This is handled by setting the _TLF_SLEEPING flag. When we get an interrupt and _TLF_SLEEPING is set, we firstly clear the MSR_EE (external interrupt enable) bit in the saved MSR value, and secondly we then return to the address in the link register, like we do for _TLF_NAPPING, but without actually handling the interrupt. Note that this is handled somewhat differently on powerbooks, so this new code will only be used on non-Apple machines. Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14[POWERPC] Define and use TLF_RESTORE_SIGMASKRoland McGrath
Replace TIF_RESTORE_SIGMASK with TLF_RESTORE_SIGMASK and define our own set_restore_sigmask() function. This saves the costly SMP-safe set_bit operation, which we do not need for the sigmask flag since TIF_SIGPENDING always has to be set too. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-29[POWERPC] Add IRQSTACKS support on ppc32Kumar Gala
This makes it possible to use separate stacks for hard and soft IRQs on 32-bit powerpc as well as on 64-bit. The code for 32-bit is just the 32-bit analog of the 64-bit code. * Added allocation and initialization of the irq stacks. We limit the stacks to be in lowmem for ppc32. * Implemented ppc32 versions of call_do_softirq() and call_handle_irq() to switch the stack pointers * Reworked how we do stack overflow detection. We now keep around the limit of the stack in the thread_struct and compare against the limit to see if we've overflowed. We can now use this on ppc64 if desired. [ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the thread_info pointer. ] Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17[POWERPC] Make Book-E debug handling SMP safeKumar Gala
global_dbcr0 needs to be a per cpu set of save areas instead of a single global on all processors. Also, we switch to using DBCR0_IDM to determine if the user space app is being debugged as its a more consistent way. In the future we should support features like hardware breakpoint and watchpoints which will have DBCR0_IDM set but not necessarily DBCR0_IC (single step). Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-11-13[POWERPC] Avoid unpaired stwcx. on some processorsBecky Bruce
The context switch code in the kernel issues a dummy stwcx. to clear the reservation, as recommended by the architecture. However, some processors can have issues if this stwcx to address A occurs while the reservation is already held to a different address B. To avoid this problem, the dummy stwcx. needs to be paired with a dummy lwarx to the same address. This adds the dummy lwarx, and creates a cpu feature bit to indicate which cpus are affected. Tested on mpc8641_hpcn_defconfig in arch/powerpc; build tested in arch/ppc. Signed-off-by: Becky Bruce <becky.bruce@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-11-01[POWERPC] 4xx: Deal with 44x virtually tagged icacheBenjamin Herrenschmidt
The 44x family has an interesting "feature" which is a virtually tagged instruction cache (yuck !). So far, we haven't dealt with it properly, which means we've been mostly lucky or people didn't report the problems, unless people have been running custom patches in their distro... This is an attempt at fixing it properly. I chose to do it by setting a global flag whenever we change a PTE that was previously marked executable, and flush the entire instruction cache upon return to user space when that happens. This is a bit heavy handed, but it's hard to do more fine grained flushes as the icbi instruction, on those processor, for some very strange reasons (since the cache is virtually mapped) still requires a valid TLB entry for reading in the target address space, which isn't something I want to deal with. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-09-14[POWERPC] Add cpu feature for SPE handlingKumar Gala
Make it so that SPE support can be determined at runtime. This is similiar to how we handle AltiVec. This allows us to have SPE support built in and work on processors with and without SPE. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-05-17[POWERPC] Fix COMMON symbol warningsKumar Gala
We get the following warnings in various ARCH=powerpc builds: WARNING: "ee_restarts" [arch/powerpc/kernel/built-in] is COMMON symbol WARNING: "fee_restarts" [arch/powerpc/kernel/built-in] is COMMON symbol WARNING: "htab_hash_searches" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "next_slot" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "mmu_hash_lock" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "primary_pteg_full" [arch/powerpc/mm/built-in] is COMMON symbol WARNING: "global_dbcr0" [arch/powerpc/kernel/built-in] is COMMON symbol Switch to moving local symbols (except mmu_hash_lock which is global) and space directive instead. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-03-22[POWERPC] Remove last_syscallAnton Blanchard
Remove last_syscall from 32bit powerpc, its been gone in 64bit for years. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-18powerpc: Use correct sequence for putting CPU into nap modePaul Mackerras
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>
2006-03-27powerpc: Unify the 32 and 64 bit idle loopsPaul Mackerras
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>
2006-03-08powerpc: Fix various syscall/signal/swapcontext bugsPaul Mackerras
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>
2006-01-18[PATCH] TIF_RESTORE_SIGMASK support for arch/powerpcDavid Woodhouse
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>
2006-01-13[PATCH] powerpc: Cleanup LOADADDR etc. asm macrosDavid Gibson
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>
2006-01-09[PATCH] Fix code that saves NVGPRS in 32-bit signal frameDavid Woodhouse
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>
2006-01-09[PATCH] syscall entry/exit revampDavid Woodhouse
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>
2005-10-28powerpc: Rename asm offset TRAP to _TRAP for 32-bitPaul Mackerras
... for consistency with 64-bit. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-26powerpc: Merge rtas.c into arch/powerpc/kernelPaul Mackerras
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>
2005-10-21[PATCH] powerpc: Merge thread_info.hDavid Gibson
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>
2005-10-20powerpc: Fix a branch-too-far link error for 32-bit targetsPaul Mackerras
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.SPaul Mackerras
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>