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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-06-02 21:17:37 +0000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-06-09 16:46:25 +1000
commite821ea70f3b4873b50056a1e0f74befed1014c09 (patch)
tree5c7808e9ab65af2577a05a79726fb211f673feb8
parentd3f6204a7d65030ba92bf43a278b3f3054353e0b (diff)
powerpc: Move VMX and VSX asm code to vector.S
Currently, load_up_altivec and give_up_altivec are duplicated in 32-bit and 64-bit. This creates a common implementation that is moved away from head_32.S, head_64.S and misc_64.S and into vector.S, using the same macros we already use for our common implementation of load_up_fpu. I also moved the VSX code over to vector.S though in that case I didn't make it build on 32-bit (yet). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
-rw-r--r--arch/powerpc/Makefile1
-rw-r--r--arch/powerpc/kernel/Makefile3
-rw-r--r--arch/powerpc/kernel/head_32.S95
-rw-r--r--arch/powerpc/kernel/head_64.S118
-rw-r--r--arch/powerpc/kernel/misc_64.S92
-rw-r--r--arch/powerpc/kernel/vector.S210
6 files changed, 213 insertions, 306 deletions
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 551fc58c05cf..bc35f4e2b81c 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -142,6 +142,7 @@ head-$(CONFIG_FSL_BOOKE) := arch/powerpc/kernel/head_fsl_booke.o
head-$(CONFIG_PPC64) += arch/powerpc/kernel/entry_64.o
head-$(CONFIG_PPC_FPU) += arch/powerpc/kernel/fpu.o
+head-$(CONFIG_ALTIVEC) += arch/powerpc/kernel/vector.o
core-y += arch/powerpc/kernel/ \
arch/powerpc/mm/ \
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 71901fbda4a5..cbc359f69e00 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -36,7 +36,7 @@ obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \
firmware.o nvram_64.o
obj64-$(CONFIG_RELOCATABLE) += reloc_64.o
obj-$(CONFIG_PPC64) += vdso64/
-obj-$(CONFIG_ALTIVEC) += vecemu.o vector.o
+obj-$(CONFIG_ALTIVEC) += vecemu.o
obj-$(CONFIG_PPC_970_NAP) += idle_power4.o
obj-$(CONFIG_PPC_OF) += of_device.o of_platform.o prom_parse.o
obj-$(CONFIG_PPC_CLOCK) += clock.o
@@ -108,6 +108,7 @@ obj-y += ppc_save_regs.o
endif
extra-$(CONFIG_PPC_FPU) += fpu.o
+extra-$(CONFIG_ALTIVEC) += vector.o
extra-$(CONFIG_PPC64) += entry_64.o
extra-y += systbl_chk.i
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index c01467f952d3..6437f905c566 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -743,101 +743,6 @@ PerformanceMonitor:
addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0xf00, performance_monitor_exception)
-#ifdef CONFIG_ALTIVEC
-/* Note that the AltiVec support is closely modeled after the FP
- * support. Changes to one are likely to be applicable to the
- * other! */
-load_up_altivec:
-/*
- * Disable AltiVec for the task which had AltiVec previously,
- * and save its AltiVec registers in its thread_struct.
- * Enables AltiVec for use in the kernel on return.
- * On SMP we know the AltiVec units are free, since we give it up every
- * switch. -- Kumar
- */
- mfmsr r5
- oris r5,r5,MSR_VEC@h
- MTMSRD(r5) /* enable use of AltiVec now */
- isync
-/*
- * For SMP, we don't do lazy AltiVec switching because it just gets too
- * horrendously complex, especially when a task switches from one CPU
- * to another. Instead we call giveup_altivec in switch_to.
- */
-#ifndef CONFIG_SMP
- tophys(r6,0)
- addis r3,r6,last_task_used_altivec@ha
- lwz r4,last_task_used_altivec@l(r3)
- cmpwi 0,r4,0
- beq 1f
- add r4,r4,r6
- addi r4,r4,THREAD /* want THREAD of last_task_used_altivec */
- SAVE_32VRS(0,r10,r4)
- mfvscr vr0
- li r10,THREAD_VSCR
- stvx vr0,r10,r4
- lwz r5,PT_REGS(r4)
- add r5,r5,r6
- lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
- lis r10,MSR_VEC@h
- andc r4,r4,r10 /* disable altivec for previous task */
- stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#endif /* CONFIG_SMP */
- /* enable use of AltiVec after return */
- oris r9,r9,MSR_VEC@h
- mfspr r5,SPRN_SPRG3 /* current task's THREAD (phys) */
- li r4,1
- li r10,THREAD_VSCR
- stw r4,THREAD_USED_VR(r5)
- lvx vr0,r10,r5
- mtvscr vr0
- REST_32VRS(0,r10,r5)
-#ifndef CONFIG_SMP
- subi r4,r5,THREAD
- sub r4,r4,r6
- stw r4,last_task_used_altivec@l(r3)
-#endif /* CONFIG_SMP */
- /* restore registers and return */
- /* we haven't used ctr or xer or lr */
- b fast_exception_return
-
-/*
- * giveup_altivec(tsk)
- * Disable AltiVec for the task given as the argument,
- * and save the AltiVec registers in its thread_struct.
- * Enables AltiVec for use in the kernel on return.
- */
-
- .globl giveup_altivec
-giveup_altivec:
- mfmsr r5
- oris r5,r5,MSR_VEC@h
- SYNC
- MTMSRD(r5) /* enable use of AltiVec now */
- isync
- cmpwi 0,r3,0
- beqlr- /* if no previous owner, done */
- addi r3,r3,THREAD /* want THREAD of task */
- lwz r5,PT_REGS(r3)
- cmpwi 0,r5,0
- SAVE_32VRS(0, r4, r3)
- mfvscr vr0
- li r4,THREAD_VSCR
- stvx vr0,r4,r3
- beq 1f
- lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
- lis r3,MSR_VEC@h
- andc r4,r4,r3 /* disable AltiVec for previous task */
- stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#ifndef CONFIG_SMP
- li r5,0
- lis r4,last_task_used_altivec@ha
- stw r5,last_task_used_altivec@l(r4)
-#endif /* CONFIG_SMP */
- blr
-#endif /* CONFIG_ALTIVEC */
/*
* This code is jumped to from the startup code to copy
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 50ef505b8fb6..382495fa90b0 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -844,124 +844,6 @@ unrecov_fer:
bl .unrecoverable_exception
b 1b
-#ifdef CONFIG_ALTIVEC
-/*
- * load_up_altivec(unused, unused, tsk)
- * Disable VMX for the task which had it previously,
- * and save its vector registers in its thread_struct.
- * Enables the VMX for use in the kernel on return.
- * On SMP we know the VMX is free, since we give it up every
- * switch (ie, no lazy save of the vector registers).
- * On entry: r13 == 'current' && last_task_used_altivec != 'current'
- */
-_STATIC(load_up_altivec)
- mfmsr r5 /* grab the current MSR */
- oris r5,r5,MSR_VEC@h
- mtmsrd r5 /* enable use of VMX now */
- isync
-
-/*
- * For SMP, we don't do lazy VMX switching because it just gets too
- * horrendously complex, especially when a task switches from one CPU
- * to another. Instead we call giveup_altvec in switch_to.
- * VRSAVE isn't dealt with here, that is done in the normal context
- * switch code. Note that we could rely on vrsave value to eventually
- * avoid saving all of the VREGs here...
- */
-#ifndef CONFIG_SMP
- ld r3,last_task_used_altivec@got(r2)
- ld r4,0(r3)
- cmpdi 0,r4,0
- beq 1f
- /* Save VMX state to last_task_used_altivec's THREAD struct */
- addi r4,r4,THREAD
- SAVE_32VRS(0,r5,r4)
- mfvscr vr0
- li r10,THREAD_VSCR
- stvx vr0,r10,r4
- /* Disable VMX for last_task_used_altivec */
- ld r5,PT_REGS(r4)
- ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
- lis r6,MSR_VEC@h
- andc r4,r4,r6
- std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#endif /* CONFIG_SMP */
- /* Hack: if we get an altivec unavailable trap with VRSAVE
- * set to all zeros, we assume this is a broken application
- * that fails to set it properly, and thus we switch it to
- * all 1's
- */
- mfspr r4,SPRN_VRSAVE
- cmpdi 0,r4,0
- bne+ 1f
- li r4,-1
- mtspr SPRN_VRSAVE,r4
-1:
- /* enable use of VMX after return */
- ld r4,PACACURRENT(r13)
- addi r5,r4,THREAD /* Get THREAD */
- oris r12,r12,MSR_VEC@h
- std r12,_MSR(r1)
- li r4,1
- li r10,THREAD_VSCR
- stw r4,THREAD_USED_VR(r5)
- lvx vr0,r10,r5
- mtvscr vr0
- REST_32VRS(0,r4,r5)
-#ifndef CONFIG_SMP
- /* Update last_task_used_math to 'current' */
- subi r4,r5,THREAD /* Back to 'current' */
- std r4,0(r3)
-#endif /* CONFIG_SMP */
- /* restore registers and return */
- blr
-#endif /* CONFIG_ALTIVEC */
-
-#ifdef CONFIG_VSX
-/*
- * load_up_vsx(unused, unused, tsk)
- * Disable VSX for the task which had it previously,
- * and save its vector registers in its thread_struct.
- * Reuse the fp and vsx saves, but first check to see if they have
- * been saved already.
- * On entry: r13 == 'current' && last_task_used_vsx != 'current'
- */
-_STATIC(load_up_vsx)
-/* Load FP and VSX registers if they haven't been done yet */
- andi. r5,r12,MSR_FP
- beql+ load_up_fpu /* skip if already loaded */
- andis. r5,r12,MSR_VEC@h
- beql+ load_up_altivec /* skip if already loaded */
-
-#ifndef CONFIG_SMP
- ld r3,last_task_used_vsx@got(r2)
- ld r4,0(r3)
- cmpdi 0,r4,0
- beq 1f
- /* Disable VSX for last_task_used_vsx */
- addi r4,r4,THREAD
- ld r5,PT_REGS(r4)
- ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
- lis r6,MSR_VSX@h
- andc r6,r4,r6
- std r6,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#endif /* CONFIG_SMP */
- ld r4,PACACURRENT(r13)
- addi r4,r4,THREAD /* Get THREAD */
- li r6,1
- stw r6,THREAD_USED_VSR(r4) /* ... also set thread used vsr */
- /* enable use of VSX after return */
- oris r12,r12,MSR_VSX@h
- std r12,_MSR(r1)
-#ifndef CONFIG_SMP
- /* Update last_task_used_math to 'current' */
- ld r4,PACACURRENT(r13)
- std r4,0(r3)
-#endif /* CONFIG_SMP */
- b fast_exception_return
-#endif /* CONFIG_VSX */
/*
* Hash table stuff
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index b9530b2395a2..a5cf9c1356a6 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -457,98 +457,6 @@ _GLOBAL(disable_kernel_fp)
isync
blr
-#ifdef CONFIG_ALTIVEC
-
-#if 0 /* this has no callers for now */
-/*
- * disable_kernel_altivec()
- * Disable the VMX.
- */
-_GLOBAL(disable_kernel_altivec)
- mfmsr r3
- rldicl r0,r3,(63-MSR_VEC_LG),1
- rldicl r3,r0,(MSR_VEC_LG+1),0
- mtmsrd r3 /* disable use of VMX now */
- isync
- blr
-#endif /* 0 */
-
-/*
- * giveup_altivec(tsk)
- * Disable VMX for the task given as the argument,
- * and save the vector registers in its thread_struct.
- * Enables the VMX for use in the kernel on return.
- */
-_GLOBAL(giveup_altivec)
- mfmsr r5
- oris r5,r5,MSR_VEC@h
- mtmsrd r5 /* enable use of VMX now */
- isync
- cmpdi 0,r3,0
- beqlr- /* if no previous owner, done */
- addi r3,r3,THREAD /* want THREAD of task */
- ld r5,PT_REGS(r3)
- cmpdi 0,r5,0
- SAVE_32VRS(0,r4,r3)
- mfvscr vr0
- li r4,THREAD_VSCR
- stvx vr0,r4,r3
- beq 1f
- ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-#ifdef CONFIG_VSX
-BEGIN_FTR_SECTION
- lis r3,(MSR_VEC|MSR_VSX)@h
-FTR_SECTION_ELSE
- lis r3,MSR_VEC@h
-ALT_FTR_SECTION_END_IFSET(CPU_FTR_VSX)
-#else
- lis r3,MSR_VEC@h
-#endif
- andc r4,r4,r3 /* disable FP for previous task */
- std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#ifndef CONFIG_SMP
- li r5,0
- ld r4,last_task_used_altivec@got(r2)
- std r5,0(r4)
-#endif /* CONFIG_SMP */
- blr
-
-#endif /* CONFIG_ALTIVEC */
-
-#ifdef CONFIG_VSX
-/*
- * __giveup_vsx(tsk)
- * Disable VSX for the task given as the argument.
- * Does NOT save vsx registers.
- * Enables the VSX for use in the kernel on return.
- */
-_GLOBAL(__giveup_vsx)
- mfmsr r5
- oris r5,r5,MSR_VSX@h
- mtmsrd r5 /* enable use of VSX now */
- isync
-
- cmpdi 0,r3,0
- beqlr- /* if no previous owner, done */
- addi r3,r3,THREAD /* want THREAD of task */
- ld r5,PT_REGS(r3)
- cmpdi 0,r5,0
- beq 1f
- ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
- lis r3,MSR_VSX@h
- andc r4,r4,r3 /* disable VSX for previous task */
- std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#ifndef CONFIG_SMP
- li r5,0
- ld r4,last_task_used_vsx@got(r2)
- std r5,0(r4)
-#endif /* CONFIG_SMP */
- blr
-
-#endif /* CONFIG_VSX */
-
/* kexec_wait(phys_cpu)
*
* wait for the flag to change, indicating this kernel is going away but
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index 49ac3d6e1399..ef36cbbc5882 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -1,5 +1,215 @@
+#include <asm/processor.h>
#include <asm/ppc_asm.h>
#include <asm/reg.h>
+#include <asm/asm-offsets.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/page.h>
+
+/*
+ * load_up_altivec(unused, unused, tsk)
+ * Disable VMX for the task which had it previously,
+ * and save its vector registers in its thread_struct.
+ * Enables the VMX for use in the kernel on return.
+ * On SMP we know the VMX is free, since we give it up every
+ * switch (ie, no lazy save of the vector registers).
+ */
+_GLOBAL(load_up_altivec)
+ mfmsr r5 /* grab the current MSR */
+ oris r5,r5,MSR_VEC@h
+ MTMSRD(r5) /* enable use of AltiVec now */
+ isync
+
+/*
+ * For SMP, we don't do lazy VMX switching because it just gets too
+ * horrendously complex, especially when a task switches from one CPU
+ * to another. Instead we call giveup_altvec in switch_to.
+ * VRSAVE isn't dealt with here, that is done in the normal context
+ * switch code. Note that we could rely on vrsave value to eventually
+ * avoid saving all of the VREGs here...
+ */
+#ifndef CONFIG_SMP
+ LOAD_REG_ADDRBASE(r3, last_task_used_altivec)
+ toreal(r3)
+ PPC_LL r4,ADDROFF(last_task_used_altivec)(r3)
+ PPC_LCMPI 0,r4,0
+ beq 1f
+
+ /* Save VMX state to last_task_used_altivec's THREAD struct */
+ toreal(r4)
+ addi r4,r4,THREAD
+ SAVE_32VRS(0,r5,r4)
+ mfvscr vr0
+ li r10,THREAD_VSCR
+ stvx vr0,r10,r4
+ /* Disable VMX for last_task_used_altivec */
+ PPC_LL r5,PT_REGS(r4)
+ toreal(r5)
+ PPC_LL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ lis r10,MSR_VEC@h
+ andc r4,r4,r10
+ PPC_STL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#endif /* CONFIG_SMP */
+
+ /* Hack: if we get an altivec unavailable trap with VRSAVE
+ * set to all zeros, we assume this is a broken application
+ * that fails to set it properly, and thus we switch it to
+ * all 1's
+ */
+ mfspr r4,SPRN_VRSAVE
+ cmpdi 0,r4,0
+ bne+ 1f
+ li r4,-1
+ mtspr SPRN_VRSAVE,r4
+1:
+ /* enable use of VMX after return */
+#ifdef CONFIG_PPC32
+ mfspr r5,SPRN_SPRG3 /* current task's THREAD (phys) */
+ oris r9,r9,MSR_VEC@h
+#else
+ ld r4,PACACURRENT(r13)
+ addi r5,r4,THREAD /* Get THREAD */
+ oris r12,r12,MSR_VEC@h
+ std r12,_MSR(r1)
+#endif
+ li r4,1
+ li r10,THREAD_VSCR
+ stw r4,THREAD_USED_VR(r5)
+ lvx vr0,r10,r5
+ mtvscr vr0
+ REST_32VRS(0,r4,r5)
+#ifndef CONFIG_SMP
+ /* Update last_task_used_math to 'current' */
+ subi r4,r5,THREAD /* Back to 'current' */
+ fromreal(r4)
+ PPC_STL r4,ADDROFF(last_task_used_math)(r3)
+#endif /* CONFIG_SMP */
+ /* restore registers and return */
+ blr
+
+/*
+ * giveup_altivec(tsk)
+ * Disable VMX for the task given as the argument,
+ * and save the vector registers in its thread_struct.
+ * Enables the VMX for use in the kernel on return.
+ */
+_GLOBAL(giveup_altivec)
+ mfmsr r5
+ oris r5,r5,MSR_VEC@h
+ SYNC
+ MTMSRD(r5) /* enable use of VMX now */
+ isync
+ PPC_LCMPI 0,r3,0
+ beqlr- /* if no previous owner, done */
+ addi r3,r3,THREAD /* want THREAD of task */
+ PPC_LL r5,PT_REGS(r3)
+ PPC_LCMPI 0,r5,0
+ SAVE_32VRS(0,r4,r3)
+ mfvscr vr0
+ li r4,THREAD_VSCR
+ stvx vr0,r4,r3
+ beq 1f
+ PPC_LL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+#ifdef CONFIG_VSX
+BEGIN_FTR_SECTION
+ lis r3,(MSR_VEC|MSR_VSX)@h
+FTR_SECTION_ELSE
+ lis r3,MSR_VEC@h
+ALT_FTR_SECTION_END_IFSET(CPU_FTR_VSX)
+#else
+ lis r3,MSR_VEC@h
+#endif
+ andc r4,r4,r3 /* disable FP for previous task */
+ PPC_STL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#ifndef CONFIG_SMP
+ li r5,0
+ LOAD_REG_ADDRBASE(r4,last_task_used_altivec)
+ PPC_STL r5,ADDROFF(last_task_used_altivec)(r4)
+#endif /* CONFIG_SMP */
+ blr
+
+#ifdef CONFIG_VSX
+
+#ifdef CONFIG_PPC32
+#error This asm code isn't ready for 32-bit kernels
+#endif
+
+/*
+ * load_up_vsx(unused, unused, tsk)
+ * Disable VSX for the task which had it previously,
+ * and save its vector registers in its thread_struct.
+ * Reuse the fp and vsx saves, but first check to see if they have
+ * been saved already.
+ */
+_GLOBAL(load_up_vsx)
+/* Load FP and VSX registers if they haven't been done yet */
+ andi. r5,r12,MSR_FP
+ beql+ load_up_fpu /* skip if already loaded */
+ andis. r5,r12,MSR_VEC@h
+ beql+ load_up_altivec /* skip if already loaded */
+
+#ifndef CONFIG_SMP
+ ld r3,last_task_used_vsx@got(r2)
+ ld r4,0(r3)
+ cmpdi 0,r4,0
+ beq 1f
+ /* Disable VSX for last_task_used_vsx */
+ addi r4,r4,THREAD
+ ld r5,PT_REGS(r4)
+ ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ lis r6,MSR_VSX@h
+ andc r6,r4,r6
+ std r6,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#endif /* CONFIG_SMP */
+ ld r4,PACACURRENT(r13)
+ addi r4,r4,THREAD /* Get THREAD */
+ li r6,1
+ stw r6,THREAD_USED_VSR(r4) /* ... also set thread used vsr */
+ /* enable use of VSX after return */
+ oris r12,r12,MSR_VSX@h
+ std r12,_MSR(r1)
+#ifndef CONFIG_SMP
+ /* Update last_task_used_math to 'current' */
+ ld r4,PACACURRENT(r13)
+ std r4,0(r3)
+#endif /* CONFIG_SMP */
+ b fast_exception_return
+
+/*
+ * __giveup_vsx(tsk)
+ * Disable VSX for the task given as the argument.
+ * Does NOT save vsx registers.
+ * Enables the VSX for use in the kernel on return.
+ */
+_GLOBAL(__giveup_vsx)
+ mfmsr r5
+ oris r5,r5,MSR_VSX@h
+ mtmsrd r5 /* enable use of VSX now */
+ isync
+
+ cmpdi 0,r3,0
+ beqlr- /* if no previous owner, done */
+ addi r3,r3,THREAD /* want THREAD of task */
+ ld r5,PT_REGS(r3)
+ cmpdi 0,r5,0
+ beq 1f
+ ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ lis r3,MSR_VSX@h
+ andc r4,r4,r3 /* disable VSX for previous task */
+ std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#ifndef CONFIG_SMP
+ li r5,0
+ ld r4,last_task_used_vsx@got(r2)
+ std r5,0(r4)
+#endif /* CONFIG_SMP */
+ blr
+
+#endif /* CONFIG_VSX */
+
/*
* The routines below are in assembler so we can closely control the