| ############################################################################### |
| # |
| # switch_to.S: context switch operation |
| # |
| # Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. |
| # Written by David Howells (dhowells@redhat.com) |
| # |
| # This program is free software; you can redistribute it and/or |
| # modify it under the terms of the GNU General Public License |
| # as published by the Free Software Foundation; either version |
| # 2 of the License, or (at your option) any later version. |
| # |
| ############################################################################### |
| #include <linux/linkage.h> |
| #include <asm/thread_info.h> |
| #include <asm/processor.h> |
| #include <asm/registers.h> |
| #include <asm/spr-regs.h> |
| |
| .macro LEDS val |
| setlos #~\val,gr27 |
| st gr27,@(gr30,gr0) |
| membar |
| dcf @(gr30,gr0) |
| .endm |
| |
| .section .sdata |
| .balign 8 |
| |
| # address of frame 0 (userspace) on current kernel stack |
| .globl __kernel_frame0_ptr |
| __kernel_frame0_ptr: |
| .long init_thread_union + THREAD_SIZE - USER_CONTEXT_SIZE |
| |
| # address of current task |
| .globl __kernel_current_task |
| __kernel_current_task: |
| .long init_task |
| |
| .section .text |
| .balign 4 |
| |
| ############################################################################### |
| # |
| # struct task_struct *__switch_to(struct thread_struct *prev_thread, |
| # struct thread_struct *next_thread, |
| # struct task_struct *prev) |
| # |
| ############################################################################### |
| .globl __switch_to |
| __switch_to: |
| # save outgoing process's context |
| sethi.p %hi(__switch_back),gr13 |
| setlo %lo(__switch_back),gr13 |
| movsg lr,gr12 |
| |
| stdi gr28,@(gr8,#__THREAD_FRAME) |
| sti sp ,@(gr8,#__THREAD_SP) |
| sti fp ,@(gr8,#__THREAD_FP) |
| stdi gr12,@(gr8,#__THREAD_LR) |
| stdi gr16,@(gr8,#__THREAD_GR(16)) |
| stdi gr18,@(gr8,#__THREAD_GR(18)) |
| stdi gr20,@(gr8,#__THREAD_GR(20)) |
| stdi gr22,@(gr8,#__THREAD_GR(22)) |
| stdi gr24,@(gr8,#__THREAD_GR(24)) |
| stdi.p gr26,@(gr8,#__THREAD_GR(26)) |
| |
| or gr8,gr8,gr22 |
| ldi.p @(gr8,#__THREAD_USER),gr8 |
| call save_user_regs |
| or gr22,gr22,gr8 |
| |
| # retrieve the new context |
| sethi.p %hi(__kernel_frame0_ptr),gr6 |
| setlo %lo(__kernel_frame0_ptr),gr6 |
| movsg psr,gr4 |
| |
| lddi.p @(gr9,#__THREAD_FRAME),gr10 |
| or gr10,gr10,gr27 ; save prev for the return value |
| |
| ldi @(gr11,#4),gr19 ; get new_current->thread_info |
| |
| lddi @(gr9,#__THREAD_SP),gr12 |
| ldi @(gr9,#__THREAD_LR),gr14 |
| ldi @(gr9,#__THREAD_PC),gr18 |
| ldi.p @(gr9,#__THREAD_FRAME0),gr7 |
| |
| # actually switch kernel contexts with ordinary exceptions disabled |
| andi gr4,#~PSR_ET,gr5 |
| movgs gr5,psr |
| |
| or.p gr10,gr0,gr28 ; set __frame |
| or gr11,gr0,gr29 ; set __current |
| or.p gr12,gr0,sp |
| or gr13,gr0,fp |
| or gr19,gr0,gr15 ; set __current_thread_info |
| |
| sti gr7,@(gr6,#0) ; set __kernel_frame0_ptr |
| sti gr29,@(gr6,#4) ; set __kernel_current_task |
| |
| movgs gr14,lr |
| bar |
| |
| srli gr15,#28,gr5 |
| subicc gr5,#0xc,gr0,icc0 |
| beq icc0,#0,111f |
| break |
| nop |
| 111: |
| |
| # jump to __switch_back or ret_from_fork as appropriate |
| # - move prev to GR8 |
| movgs gr4,psr |
| jmpl.p @(gr18,gr0) |
| or gr27,gr27,gr8 |
| |
| ############################################################################### |
| # |
| # restore incoming process's context |
| # - on entry: |
| # - SP, FP, LR, GR15, GR28 and GR29 will have been set up appropriately |
| # - GR8 will point to the outgoing task_struct |
| # - GR9 will point to the incoming thread_struct |
| # |
| ############################################################################### |
| __switch_back: |
| lddi @(gr9,#__THREAD_GR(16)),gr16 |
| lddi @(gr9,#__THREAD_GR(18)),gr18 |
| lddi @(gr9,#__THREAD_GR(20)),gr20 |
| lddi @(gr9,#__THREAD_GR(22)),gr22 |
| lddi @(gr9,#__THREAD_GR(24)),gr24 |
| lddi @(gr9,#__THREAD_GR(26)),gr26 |
| |
| # fall through into restore_user_regs() |
| ldi.p @(gr9,#__THREAD_USER),gr8 |
| or gr8,gr8,gr9 |
| |
| ############################################################################### |
| # |
| # restore extra general regs and FP/Media regs |
| # - void *restore_user_regs(const struct user_context *target, void *retval) |
| # - on entry: |
| # - GR8 will point to the user context to swap in |
| # - GR9 will contain the value to be returned in GR8 (prev task on context switch) |
| # |
| ############################################################################### |
| .globl restore_user_regs |
| restore_user_regs: |
| movsg hsr0,gr6 |
| ori gr6,#HSR0_GRHE|HSR0_FRLE|HSR0_FRHE,gr6 |
| movgs gr6,hsr0 |
| movsg hsr0,gr6 |
| |
| movsg psr,gr7 |
| ori gr7,#PSR_EF|PSR_EM,gr7 |
| movgs gr7,psr |
| movsg psr,gr7 |
| srli gr7,#24,gr7 |
| bar |
| |
| lddi @(gr8,#__FPMEDIA_MSR(0)),gr4 |
| |
| movgs gr4,msr0 |
| movgs gr5,msr1 |
| |
| lddfi @(gr8,#__FPMEDIA_ACC(0)),fr16 |
| lddfi @(gr8,#__FPMEDIA_ACC(2)),fr18 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(0)),fr20 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(1)),fr21 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(2)),fr22 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(3)),fr23 |
| |
| mwtacc fr16,acc0 |
| mwtacc fr17,acc1 |
| mwtacc fr18,acc2 |
| mwtacc fr19,acc3 |
| mwtaccg fr20,accg0 |
| mwtaccg fr21,accg1 |
| mwtaccg fr22,accg2 |
| mwtaccg fr23,accg3 |
| |
| # some CPUs have extra ACCx and ACCGx regs and maybe FSRx regs |
| subicc.p gr7,#0x50,gr0,icc0 |
| subicc gr7,#0x31,gr0,icc1 |
| beq icc0,#0,__restore_acc_fr451 |
| beq icc1,#0,__restore_acc_fr555 |
| __restore_acc_cont: |
| |
| # some CPU's have GR32-GR63 |
| setlos #HSR0_FRHE,gr4 |
| andcc gr6,gr4,gr0,icc0 |
| beq icc0,#1,__restore_skip_gr32_gr63 |
| |
| lddi @(gr8,#__INT_GR(32)),gr32 |
| lddi @(gr8,#__INT_GR(34)),gr34 |
| lddi @(gr8,#__INT_GR(36)),gr36 |
| lddi @(gr8,#__INT_GR(38)),gr38 |
| lddi @(gr8,#__INT_GR(40)),gr40 |
| lddi @(gr8,#__INT_GR(42)),gr42 |
| lddi @(gr8,#__INT_GR(44)),gr44 |
| lddi @(gr8,#__INT_GR(46)),gr46 |
| lddi @(gr8,#__INT_GR(48)),gr48 |
| lddi @(gr8,#__INT_GR(50)),gr50 |
| lddi @(gr8,#__INT_GR(52)),gr52 |
| lddi @(gr8,#__INT_GR(54)),gr54 |
| lddi @(gr8,#__INT_GR(56)),gr56 |
| lddi @(gr8,#__INT_GR(58)),gr58 |
| lddi @(gr8,#__INT_GR(60)),gr60 |
| lddi @(gr8,#__INT_GR(62)),gr62 |
| __restore_skip_gr32_gr63: |
| |
| # all CPU's have FR0-FR31 |
| lddfi @(gr8,#__FPMEDIA_FR( 0)),fr0 |
| lddfi @(gr8,#__FPMEDIA_FR( 2)),fr2 |
| lddfi @(gr8,#__FPMEDIA_FR( 4)),fr4 |
| lddfi @(gr8,#__FPMEDIA_FR( 6)),fr6 |
| lddfi @(gr8,#__FPMEDIA_FR( 8)),fr8 |
| lddfi @(gr8,#__FPMEDIA_FR(10)),fr10 |
| lddfi @(gr8,#__FPMEDIA_FR(12)),fr12 |
| lddfi @(gr8,#__FPMEDIA_FR(14)),fr14 |
| lddfi @(gr8,#__FPMEDIA_FR(16)),fr16 |
| lddfi @(gr8,#__FPMEDIA_FR(18)),fr18 |
| lddfi @(gr8,#__FPMEDIA_FR(20)),fr20 |
| lddfi @(gr8,#__FPMEDIA_FR(22)),fr22 |
| lddfi @(gr8,#__FPMEDIA_FR(24)),fr24 |
| lddfi @(gr8,#__FPMEDIA_FR(26)),fr26 |
| lddfi @(gr8,#__FPMEDIA_FR(28)),fr28 |
| lddfi.p @(gr8,#__FPMEDIA_FR(30)),fr30 |
| |
| # some CPU's have FR32-FR63 |
| setlos #HSR0_FRHE,gr4 |
| andcc gr6,gr4,gr0,icc0 |
| beq icc0,#1,__restore_skip_fr32_fr63 |
| |
| lddfi @(gr8,#__FPMEDIA_FR(32)),fr32 |
| lddfi @(gr8,#__FPMEDIA_FR(34)),fr34 |
| lddfi @(gr8,#__FPMEDIA_FR(36)),fr36 |
| lddfi @(gr8,#__FPMEDIA_FR(38)),fr38 |
| lddfi @(gr8,#__FPMEDIA_FR(40)),fr40 |
| lddfi @(gr8,#__FPMEDIA_FR(42)),fr42 |
| lddfi @(gr8,#__FPMEDIA_FR(44)),fr44 |
| lddfi @(gr8,#__FPMEDIA_FR(46)),fr46 |
| lddfi @(gr8,#__FPMEDIA_FR(48)),fr48 |
| lddfi @(gr8,#__FPMEDIA_FR(50)),fr50 |
| lddfi @(gr8,#__FPMEDIA_FR(52)),fr52 |
| lddfi @(gr8,#__FPMEDIA_FR(54)),fr54 |
| lddfi @(gr8,#__FPMEDIA_FR(56)),fr56 |
| lddfi @(gr8,#__FPMEDIA_FR(58)),fr58 |
| lddfi @(gr8,#__FPMEDIA_FR(60)),fr60 |
| lddfi @(gr8,#__FPMEDIA_FR(62)),fr62 |
| __restore_skip_fr32_fr63: |
| |
| lddi @(gr8,#__FPMEDIA_FNER(0)),gr4 |
| movsg fner0,gr4 |
| movsg fner1,gr5 |
| or.p gr9,gr9,gr8 |
| bralr |
| |
| # the FR451 also has ACC8-11/ACCG8-11 regs (but not 4-7...) |
| __restore_acc_fr451: |
| lddfi @(gr8,#__FPMEDIA_ACC(4)),fr16 |
| lddfi @(gr8,#__FPMEDIA_ACC(6)),fr18 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(4)),fr20 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(5)),fr21 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(6)),fr22 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(7)),fr23 |
| |
| mwtacc fr16,acc8 |
| mwtacc fr17,acc9 |
| mwtacc fr18,acc10 |
| mwtacc fr19,acc11 |
| mwtaccg fr20,accg8 |
| mwtaccg fr21,accg9 |
| mwtaccg fr22,accg10 |
| mwtaccg fr23,accg11 |
| bra __restore_acc_cont |
| |
| # the FR555 also has ACC4-7/ACCG4-7 regs and an FSR0 reg |
| __restore_acc_fr555: |
| lddfi @(gr8,#__FPMEDIA_ACC(4)),fr16 |
| lddfi @(gr8,#__FPMEDIA_ACC(6)),fr18 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(4)),fr20 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(5)),fr21 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(6)),fr22 |
| ldbfi @(gr8,#__FPMEDIA_ACCG(7)),fr23 |
| |
| mnop.p |
| mwtacc fr16,acc4 |
| mnop.p |
| mwtacc fr17,acc5 |
| mnop.p |
| mwtacc fr18,acc6 |
| mnop.p |
| mwtacc fr19,acc7 |
| mnop.p |
| mwtaccg fr20,accg4 |
| mnop.p |
| mwtaccg fr21,accg5 |
| mnop.p |
| mwtaccg fr22,accg6 |
| mnop.p |
| mwtaccg fr23,accg7 |
| |
| ldi @(gr8,#__FPMEDIA_FSR(0)),gr4 |
| movgs gr4,fsr0 |
| |
| bra __restore_acc_cont |
| |
| |
| ############################################################################### |
| # |
| # save extra general regs and FP/Media regs |
| # - void save_user_regs(struct user_context *target) |
| # |
| ############################################################################### |
| .globl save_user_regs |
| save_user_regs: |
| movsg hsr0,gr6 |
| ori gr6,#HSR0_GRHE|HSR0_FRLE|HSR0_FRHE,gr6 |
| movgs gr6,hsr0 |
| movsg hsr0,gr6 |
| |
| movsg psr,gr7 |
| ori gr7,#PSR_EF|PSR_EM,gr7 |
| movgs gr7,psr |
| movsg psr,gr7 |
| srli gr7,#24,gr7 |
| bar |
| |
| movsg fner0,gr4 |
| movsg fner1,gr5 |
| stdi.p gr4,@(gr8,#__FPMEDIA_FNER(0)) |
| |
| # some CPU's have GR32-GR63 |
| setlos #HSR0_GRHE,gr4 |
| andcc gr6,gr4,gr0,icc0 |
| beq icc0,#1,__save_skip_gr32_gr63 |
| |
| stdi gr32,@(gr8,#__INT_GR(32)) |
| stdi gr34,@(gr8,#__INT_GR(34)) |
| stdi gr36,@(gr8,#__INT_GR(36)) |
| stdi gr38,@(gr8,#__INT_GR(38)) |
| stdi gr40,@(gr8,#__INT_GR(40)) |
| stdi gr42,@(gr8,#__INT_GR(42)) |
| stdi gr44,@(gr8,#__INT_GR(44)) |
| stdi gr46,@(gr8,#__INT_GR(46)) |
| stdi gr48,@(gr8,#__INT_GR(48)) |
| stdi gr50,@(gr8,#__INT_GR(50)) |
| stdi gr52,@(gr8,#__INT_GR(52)) |
| stdi gr54,@(gr8,#__INT_GR(54)) |
| stdi gr56,@(gr8,#__INT_GR(56)) |
| stdi gr58,@(gr8,#__INT_GR(58)) |
| stdi gr60,@(gr8,#__INT_GR(60)) |
| stdi gr62,@(gr8,#__INT_GR(62)) |
| __save_skip_gr32_gr63: |
| |
| # all CPU's have FR0-FR31 |
| stdfi fr0 ,@(gr8,#__FPMEDIA_FR( 0)) |
| stdfi fr2 ,@(gr8,#__FPMEDIA_FR( 2)) |
| stdfi fr4 ,@(gr8,#__FPMEDIA_FR( 4)) |
| stdfi fr6 ,@(gr8,#__FPMEDIA_FR( 6)) |
| stdfi fr8 ,@(gr8,#__FPMEDIA_FR( 8)) |
| stdfi fr10,@(gr8,#__FPMEDIA_FR(10)) |
| stdfi fr12,@(gr8,#__FPMEDIA_FR(12)) |
| stdfi fr14,@(gr8,#__FPMEDIA_FR(14)) |
| stdfi fr16,@(gr8,#__FPMEDIA_FR(16)) |
| stdfi fr18,@(gr8,#__FPMEDIA_FR(18)) |
| stdfi fr20,@(gr8,#__FPMEDIA_FR(20)) |
| stdfi fr22,@(gr8,#__FPMEDIA_FR(22)) |
| stdfi fr24,@(gr8,#__FPMEDIA_FR(24)) |
| stdfi fr26,@(gr8,#__FPMEDIA_FR(26)) |
| stdfi fr28,@(gr8,#__FPMEDIA_FR(28)) |
| stdfi.p fr30,@(gr8,#__FPMEDIA_FR(30)) |
| |
| # some CPU's have FR32-FR63 |
| setlos #HSR0_FRHE,gr4 |
| andcc gr6,gr4,gr0,icc0 |
| beq icc0,#1,__save_skip_fr32_fr63 |
| |
| stdfi fr32,@(gr8,#__FPMEDIA_FR(32)) |
| stdfi fr34,@(gr8,#__FPMEDIA_FR(34)) |
| stdfi fr36,@(gr8,#__FPMEDIA_FR(36)) |
| stdfi fr38,@(gr8,#__FPMEDIA_FR(38)) |
| stdfi fr40,@(gr8,#__FPMEDIA_FR(40)) |
| stdfi fr42,@(gr8,#__FPMEDIA_FR(42)) |
| stdfi fr44,@(gr8,#__FPMEDIA_FR(44)) |
| stdfi fr46,@(gr8,#__FPMEDIA_FR(46)) |
| stdfi fr48,@(gr8,#__FPMEDIA_FR(48)) |
| stdfi fr50,@(gr8,#__FPMEDIA_FR(50)) |
| stdfi fr52,@(gr8,#__FPMEDIA_FR(52)) |
| stdfi fr54,@(gr8,#__FPMEDIA_FR(54)) |
| stdfi fr56,@(gr8,#__FPMEDIA_FR(56)) |
| stdfi fr58,@(gr8,#__FPMEDIA_FR(58)) |
| stdfi fr60,@(gr8,#__FPMEDIA_FR(60)) |
| stdfi fr62,@(gr8,#__FPMEDIA_FR(62)) |
| __save_skip_fr32_fr63: |
| |
| mrdacc acc0 ,fr4 |
| mrdacc acc1 ,fr5 |
| |
| stdfi.p fr4 ,@(gr8,#__FPMEDIA_ACC(0)) |
| |
| mrdacc acc2 ,fr6 |
| mrdacc acc3 ,fr7 |
| |
| stdfi.p fr6 ,@(gr8,#__FPMEDIA_ACC(2)) |
| |
| mrdaccg accg0,fr4 |
| stbfi.p fr4 ,@(gr8,#__FPMEDIA_ACCG(0)) |
| |
| mrdaccg accg1,fr5 |
| stbfi.p fr5 ,@(gr8,#__FPMEDIA_ACCG(1)) |
| |
| mrdaccg accg2,fr6 |
| stbfi.p fr6 ,@(gr8,#__FPMEDIA_ACCG(2)) |
| |
| mrdaccg accg3,fr7 |
| stbfi fr7 ,@(gr8,#__FPMEDIA_ACCG(3)) |
| |
| movsg msr0 ,gr4 |
| movsg msr1 ,gr5 |
| |
| stdi gr4 ,@(gr8,#__FPMEDIA_MSR(0)) |
| |
| # some CPUs have extra ACCx and ACCGx regs and maybe FSRx regs |
| subicc.p gr7,#0x50,gr0,icc0 |
| subicc gr7,#0x31,gr0,icc1 |
| beq icc0,#0,__save_acc_fr451 |
| beq icc1,#0,__save_acc_fr555 |
| __save_acc_cont: |
| |
| lddfi @(gr8,#__FPMEDIA_FR(4)),fr4 |
| lddfi.p @(gr8,#__FPMEDIA_FR(6)),fr6 |
| bralr |
| |
| # the FR451 also has ACC8-11/ACCG8-11 regs (but not 4-7...) |
| __save_acc_fr451: |
| mrdacc acc8 ,fr4 |
| mrdacc acc9 ,fr5 |
| |
| stdfi.p fr4 ,@(gr8,#__FPMEDIA_ACC(4)) |
| |
| mrdacc acc10,fr6 |
| mrdacc acc11,fr7 |
| |
| stdfi.p fr6 ,@(gr8,#__FPMEDIA_ACC(6)) |
| |
| mrdaccg accg8,fr4 |
| stbfi.p fr4 ,@(gr8,#__FPMEDIA_ACCG(4)) |
| |
| mrdaccg accg9,fr5 |
| stbfi.p fr5 ,@(gr8,#__FPMEDIA_ACCG(5)) |
| |
| mrdaccg accg10,fr6 |
| stbfi.p fr6 ,@(gr8,#__FPMEDIA_ACCG(6)) |
| |
| mrdaccg accg11,fr7 |
| stbfi fr7 ,@(gr8,#__FPMEDIA_ACCG(7)) |
| bra __save_acc_cont |
| |
| # the FR555 also has ACC4-7/ACCG4-7 regs and an FSR0 reg |
| __save_acc_fr555: |
| mnop.p |
| mrdacc acc4 ,fr4 |
| mnop.p |
| mrdacc acc5 ,fr5 |
| |
| stdfi fr4 ,@(gr8,#__FPMEDIA_ACC(4)) |
| |
| mnop.p |
| mrdacc acc6 ,fr6 |
| mnop.p |
| mrdacc acc7 ,fr7 |
| |
| stdfi fr6 ,@(gr8,#__FPMEDIA_ACC(6)) |
| |
| mnop.p |
| mrdaccg accg4,fr4 |
| stbfi fr4 ,@(gr8,#__FPMEDIA_ACCG(4)) |
| |
| mnop.p |
| mrdaccg accg5,fr5 |
| stbfi fr5 ,@(gr8,#__FPMEDIA_ACCG(5)) |
| |
| mnop.p |
| mrdaccg accg6,fr6 |
| stbfi fr6 ,@(gr8,#__FPMEDIA_ACCG(6)) |
| |
| mnop.p |
| mrdaccg accg7,fr7 |
| stbfi fr7 ,@(gr8,#__FPMEDIA_ACCG(7)) |
| |
| movsg fsr0 ,gr4 |
| sti gr4 ,@(gr8,#__FPMEDIA_FSR(0)) |
| bra __save_acc_cont |
