summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/fpu.S
AgeCommit message (Collapse)Author
2012-07-10powerpc: Enforce usage of R0-R31 where possibleMichael Neuling
Enforce the use of R0-R31 in macros where possible now we have all the fixes in. R0-R31 macros are removed here so that can't be used anymore. They should not be defined anywhere. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-07-10powerpc: Fix usage of register macros getting ready for %r0 changeMichael Neuling
Anything that uses a constructed instruction (ie. from ppc-opcode.h), need to use the new R0 macro, as %r0 is not going to work. Also convert usages of macros where we are just determining an offset (usually for a load/store), like: std r14,STK_REG(r14)(r1) Can't use STK_REG(r14) as %r14 doesn't work in the STK_REG macro since it's just calculating an offset. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-11-29powerpc: Remove second definition of STACK_FRAME_OVERHEADStephen Rothwell
Since STACK_FRAME_OVERHEAD is defined in asm/ptrace.h and that is ASSEMBER safe, we can just include that instead of going via asm-offsets.h. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-09-02powerpc: Remove fpscr use from [kvm_]cvt_{fd,df}Andreas Schwab
Neither lfs nor stfs touch the fpscr, so remove the restore/save of it around them. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20powerpc: Use names rather than numbers for SPRGs (v2)Benjamin Herrenschmidt
The kernel uses SPRG registers for various purposes, typically in low level assembly code as scratch registers or to hold per-cpu global infos such as the PACA or the current thread_info pointer. We want to be able to easily shuffle the usage of those registers as some implementations have specific constraints realted to some of them, for example, some have userspace readable aliases, etc.. and the current choice isn't always the best. This patch should not change any code generation, and replaces the usage of SPRN_SPRGn everywhere in the kernel with a named replacement and adds documentation next to the definition of the names as to what those are used for on each processor family. The only parts that still use the original numbers are bits of KVM or suspend/resume code that just blindly needs to save/restore all the SPRGs. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-04-07powerpc: Disable VSX or current process in giveup_fpu/altivecMichael Neuling
When we call giveup_fpu, we need to need to turn off VSX for the current process. If we don't, on return to userspace it may execute a VSX instruction before the next FP instruction, and not have its register state refreshed correctly from the thread_struct. Ditto for altivec. This caused a bug where an unaligned lfs or stfs results in fix_alignment calling giveup_fpu so it can use the FPRs (in order to do a single <-> double conversion), and then returning to userspace with FP off but VSX on. Then if a VSX instruction is executed, before another FP instruction, it will proceed without another exception and hence have the incorrect register state for VSX registers 0-31. lfs unaligned <- alignment exception turns FP off but leaves VSX on VSX instruction <- no exception since VSX on, hence we get the wrong VSX register values for VSX registers 0-31, which overlap the FPRs. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01powerpc: Add VSX context save/restore, ptrace and signal supportMichael Neuling
This patch extends the floating point save and restore code to use the VSX load/stores when VSX is available. This will make FP context save/restore marginally slower on FP only code, when VSX is available, as it has to load/store 128bits rather than just 64bits. Mixing FP, VMX and VSX code will get constant architected state. The signals interface is extended to enable access to VSR 0-31 doubleword 1 after discussions with tool chain maintainers. Backward compatibility is maintained. The ptrace interface is also extended to allow access to VSR 0-31 full registers. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01powerpc: Add VSX assembler code macrosMichael Neuling
This adds the macros for the VSX load/store instruction as most binutils are not going to support this for a while. Also add VSX register save/restore macros and vsr[0-63] register definitions. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01powerpc: Make load_up_fpu and load_up_altivec callableMichael Neuling
Make load_up_fpu and load_up_altivec callable so they can be reused by the VSX code. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-30[POWERPC] Restore copyright notice in arch/powerpc/kernel/fpu.SPaul Mackerras
This code got moved from head.S but the copyright notice on head.S didn't get transferred with it. Noticed by Cort Dougan <cort@fsmlabs.com>. 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>
2006-06-15[POWERPC] 64bit FPSCR supportAnton Blanchard
Forthcoming machines will extend the FPSCR to 64 bits. We already had a 64-bit save area for the FPSCR, but we need to use a new form of the mtfsf instruction. Fortunately this new form is decoded as an ordinary mtfsf by existing 64-bit processors. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-07powerpc/64: Fix bug in setting floating-point exception modePaul Mackerras
When loading up the FPU, we were using a 'ld' (load doubleword) instruction to get the FP exception mode from the thread_struct, but it's only an int field. This changes the ld to lwz (load word and zero-extend). Signed-off-by: Paul Mackerras <paulus@samba.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>
2005-11-10[PATCH] powerpc: Consolidate asm compatibility macrosDavid Gibson
This patch consolidates macros used to generate assembly for compatibility across different CPUs or configs. A new header, asm-powerpc/asm-compat.h contains the main compatibility macros. It uses some preprocessor magic to make the macros suitable both for use in .S files, and in inline asm in .c files. Headers (bitops.h, uaccess.h, atomic.h, bug.h) which had their own such compatibility macros are changed to use asm-compat.h. ppc_asm.h is now for use in .S files *only*, and a #error enforces that. As such, we're a lot more careless about namespace pollution here than in asm-compat.h. While we're at it, this patch adds a call to the PPC405_ERR77 macro in futex.h which should have had it already, but didn't. Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc). Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-27powerpc: Introduce toreal/fromreal assembly macrosPaul Mackerras
On 32-bit platforms, these convert from kernel virtual addresses to real (physical addresses), like tophys/tovirt but they use the same register for the source and destination. On 64-bit platforms, they do nothing because the hardware ignores the top two bits of the address in real mode. These new macros are used in fpu.S now. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-27[PATCH] powerpc: Fix handling of fpscr on 64-bitDavid Gibson
The recent merge of fpu.S broken the handling of fpscr for ARCH=powerpc and CONFIG_PPC64=y. FP registers could be corrupted, leading to strange random application crashes. The confusion arises, because the thread_struct has (and requires) a 64-bit area to save the fpscr, because we use load/store double instructions to get it in to/out of the FPU. However, only the low 32-bits are actually used, so we want to treat it as a 32-bit quantity when manipulating its bits to avoid extra load/stores on 32-bit. This patch replaces the current definition with a structure of two 32-bit quantities (pad and val), to clarify things as much as is possible. The 'val' field is used when manipulating bits, the structure itself is used when obtaining the address for loading/unloading the value from the FPU. While we're at it, consolidate the 4 (!) almost identical versions of cvt_fd() and cvt_df() (arch/ppc/kernel/misc.S, arch/ppc64/kernel/misc.S, arch/powerpc/kernel/misc_32.S, arch/powerpc/kernel/misc_64.S) into a single version in fpu.S. The new version takes a pointer to thread_struct and applies the correct offset itself, rather than a pointer to the fpscr field itself, again to avoid confusion as to which is the correct field to use. Finally, this patch makes ARCH=ppc64 also use the consolidated fpu.S code, which it previously did not. Built for G5 (ARCH=ppc64 and ARCH=powerpc), 32-bit powermac (ARCH=ppc and ARCH=powerpc) and Walnut (ARCH=ppc, CONFIG_MATH_EMULATION=y). Booted on G5 (ARCH=powerpc) and things which previously fell over no longer do. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10powerpc: Use reg.h instead of processor.h when we just want reg namesPaul Mackerras
Now that the register names and bit definitions are all in reg.h, use that instead of processor.h in assembly code in a few places. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-06powerpc: Define 32/64 bit asm macros and use them in fpu.SPaul Mackerras
These macros help in writing assembly code that works for both ppc32 and ppc64. With this we now have a common fpu.S. This takes out load_up_fpu from head_64.S. 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>