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2010-09-02powerpc: mtmsrd not definedSean MacLennan
Replace the BOOK3S_64 specific mtmsrd with the generic MTMSRD macro. Only enable ldstfp when CONFIG_PPC_FPU is set. Signed-off-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-22powerpc: Emulate most Book I instructions in emulate_step()Paul Mackerras
This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-02-10powerpc: Don't emulate mr. instructionsAnanth N Mavinakayanahalli
Currently emulate_step() emulates mr. instructions without updating cr0 and this can be disastrous. Don't emulate mr. This bug has been around for a while, but I am not sure if its a worthy -stable candidate. I'll leave it to Ben do decide. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2007-04-24[POWERPC] Emulate more instructions in softwareAnanth N Mavinakayanahalli
Emulate a few more instructions in software - especially useful during singlestepping (xmon/kprobes). Instructions emulated with this patch are mfcr/mtcr rX, mfxer/mtxer rX, mflr/mtlr rX, mfctr/mtctr rX and mr rA,rB. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-11-01[POWERPC] Disallow kprobes on emulate_step and branch_takenGui,Jian
On powerpc, probing on emulate_step function will crash 2.6.18.1 when it is triggered. When kprobe is triggered, emulate_step() is on its kernel path and will cause recursive kprobe fault. And branch_taken() is called in emulate_step(). This disallows kprobes on both of them. 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>
2006-03-27[PATCH] powerpc: fix various sparse warningsStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28powerpc: Make single-stepping emulation (mostly) usable on 32-bitPaul Mackerras
The sc instruction emulation can't be done the same way on 32-bit as 64-bit yet, but this should work OK. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-26powerpc: Merge enough to start building in arch/powerpc.Paul Mackerras
This creates the directory structure under arch/powerpc and a bunch of Kconfig files. It does a first-cut merge of arch/powerpc/mm, arch/powerpc/lib and arch/powerpc/platforms/powermac. This is enough to build a 32-bit powermac kernel with ARCH=powerpc. For now we are getting some unmerged files from arch/ppc/kernel and arch/ppc/syslib, or arch/ppc64/kernel. This makes some minor changes to files in those directories and files outside arch/powerpc. The boot directory is still not merged. That's going to be interesting. Signed-off-by: Paul Mackerras <paulus@samba.org>