| #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 |
| cmpwi 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_SPRG_THREAD /* 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_altivec to 'current' */ |
| subi r4,r5,THREAD /* Back to 'current' */ |
| fromreal(r4) |
| PPC_STL r4,ADDROFF(last_task_used_altivec)(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_vsx 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 |
| * usage of floating-point registers. These routines must be called |
| * with preempt disabled. |
| */ |
| #ifdef CONFIG_PPC32 |
| .data |
| fpzero: |
| .long 0 |
| fpone: |
| .long 0x3f800000 /* 1.0 in single-precision FP */ |
| fphalf: |
| .long 0x3f000000 /* 0.5 in single-precision FP */ |
| |
| #define LDCONST(fr, name) \ |
| lis r11,name@ha; \ |
| lfs fr,name@l(r11) |
| #else |
| |
| .section ".toc","aw" |
| fpzero: |
| .tc FD_0_0[TC],0 |
| fpone: |
| .tc FD_3ff00000_0[TC],0x3ff0000000000000 /* 1.0 */ |
| fphalf: |
| .tc FD_3fe00000_0[TC],0x3fe0000000000000 /* 0.5 */ |
| |
| #define LDCONST(fr, name) \ |
| lfd fr,name@toc(r2) |
| #endif |
| |
| .text |
| /* |
| * Internal routine to enable floating point and set FPSCR to 0. |
| * Don't call it from C; it doesn't use the normal calling convention. |
| */ |
| fpenable: |
| #ifdef CONFIG_PPC32 |
| stwu r1,-64(r1) |
| #else |
| stdu r1,-64(r1) |
| #endif |
| mfmsr r10 |
| ori r11,r10,MSR_FP |
| mtmsr r11 |
| isync |
| stfd fr0,24(r1) |
| stfd fr1,16(r1) |
| stfd fr31,8(r1) |
| LDCONST(fr1, fpzero) |
| mffs fr31 |
| MTFSF_L(fr1) |
| blr |
| |
| fpdisable: |
| mtlr r12 |
| MTFSF_L(fr31) |
| lfd fr31,8(r1) |
| lfd fr1,16(r1) |
| lfd fr0,24(r1) |
| mtmsr r10 |
| isync |
| addi r1,r1,64 |
| blr |
| |
| /* |
| * Vector add, floating point. |
| */ |
| _GLOBAL(vaddfp) |
| mflr r12 |
| bl fpenable |
| li r0,4 |
| mtctr r0 |
| li r6,0 |
| 1: lfsx fr0,r4,r6 |
| lfsx fr1,r5,r6 |
| fadds fr0,fr0,fr1 |
| stfsx fr0,r3,r6 |
| addi r6,r6,4 |
| bdnz 1b |
| b fpdisable |
| |
| /* |
| * Vector subtract, floating point. |
| */ |
| _GLOBAL(vsubfp) |
| mflr r12 |
| bl fpenable |
| li r0,4 |
| mtctr r0 |
| li r6,0 |
| 1: lfsx fr0,r4,r6 |
| lfsx fr1,r5,r6 |
| fsubs fr0,fr0,fr1 |
| stfsx fr0,r3,r6 |
| addi r6,r6,4 |
| bdnz 1b |
| b fpdisable |
| |
| /* |
| * Vector multiply and add, floating point. |
| */ |
| _GLOBAL(vmaddfp) |
| mflr r12 |
| bl fpenable |
| stfd fr2,32(r1) |
| li r0,4 |
| mtctr r0 |
| li r7,0 |
| 1: lfsx fr0,r4,r7 |
| lfsx fr1,r5,r7 |
| lfsx fr2,r6,r7 |
| fmadds fr0,fr0,fr2,fr1 |
| stfsx fr0,r3,r7 |
| addi r7,r7,4 |
| bdnz 1b |
| lfd fr2,32(r1) |
| b fpdisable |
| |
| /* |
| * Vector negative multiply and subtract, floating point. |
| */ |
| _GLOBAL(vnmsubfp) |
| mflr r12 |
| bl fpenable |
| stfd fr2,32(r1) |
| li r0,4 |
| mtctr r0 |
| li r7,0 |
| 1: lfsx fr0,r4,r7 |
| lfsx fr1,r5,r7 |
| lfsx fr2,r6,r7 |
| fnmsubs fr0,fr0,fr2,fr1 |
| stfsx fr0,r3,r7 |
| addi r7,r7,4 |
| bdnz 1b |
| lfd fr2,32(r1) |
| b fpdisable |
| |
| /* |
| * Vector reciprocal estimate. We just compute 1.0/x. |
| * r3 -> destination, r4 -> source. |
| */ |
| _GLOBAL(vrefp) |
| mflr r12 |
| bl fpenable |
| li r0,4 |
| LDCONST(fr1, fpone) |
| mtctr r0 |
| li r6,0 |
| 1: lfsx fr0,r4,r6 |
| fdivs fr0,fr1,fr0 |
| stfsx fr0,r3,r6 |
| addi r6,r6,4 |
| bdnz 1b |
| b fpdisable |
| |
| /* |
| * Vector reciprocal square-root estimate, floating point. |
| * We use the frsqrte instruction for the initial estimate followed |
| * by 2 iterations of Newton-Raphson to get sufficient accuracy. |
| * r3 -> destination, r4 -> source. |
| */ |
| _GLOBAL(vrsqrtefp) |
| mflr r12 |
| bl fpenable |
| stfd fr2,32(r1) |
| stfd fr3,40(r1) |
| stfd fr4,48(r1) |
| stfd fr5,56(r1) |
| li r0,4 |
| LDCONST(fr4, fpone) |
| LDCONST(fr5, fphalf) |
| mtctr r0 |
| li r6,0 |
| 1: lfsx fr0,r4,r6 |
| frsqrte fr1,fr0 /* r = frsqrte(s) */ |
| fmuls fr3,fr1,fr0 /* r * s */ |
| fmuls fr2,fr1,fr5 /* r * 0.5 */ |
| fnmsubs fr3,fr1,fr3,fr4 /* 1 - s * r * r */ |
| fmadds fr1,fr2,fr3,fr1 /* r = r + 0.5 * r * (1 - s * r * r) */ |
| fmuls fr3,fr1,fr0 /* r * s */ |
| fmuls fr2,fr1,fr5 /* r * 0.5 */ |
| fnmsubs fr3,fr1,fr3,fr4 /* 1 - s * r * r */ |
| fmadds fr1,fr2,fr3,fr1 /* r = r + 0.5 * r * (1 - s * r * r) */ |
| stfsx fr1,r3,r6 |
| addi r6,r6,4 |
| bdnz 1b |
| lfd fr5,56(r1) |
| lfd fr4,48(r1) |
| lfd fr3,40(r1) |
| lfd fr2,32(r1) |
| b fpdisable |
