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Diffstat (limited to 'arch/sh64/kernel/switchto.S')
| -rw-r--r-- | arch/sh64/kernel/switchto.S | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/arch/sh64/kernel/switchto.S b/arch/sh64/kernel/switchto.S deleted file mode 100644 index 45b2d90eed7d..000000000000 --- a/arch/sh64/kernel/switchto.S +++ /dev/null @@ -1,198 +0,0 @@ -/* - * arch/sh64/kernel/switchto.S - * - * sh64 context switch - * - * Copyright (C) 2004 Richard Curnow - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. -*/ - - .section .text..SHmedia32,"ax" - .little - - .balign 32 - - .type sh64_switch_to,@function - .global sh64_switch_to - .global __sh64_switch_to_end -sh64_switch_to: - -/* Incoming args - r2 - prev - r3 - &prev->thread - r4 - next - r5 - &next->thread - - Outgoing results - r2 - last (=prev) : this just stays in r2 throughout - - Want to create a full (struct pt_regs) on the stack to allow backtracing - functions to work. However, we only need to populate the callee-save - register slots in this structure; since we're a function our ancestors must - have themselves preserved all caller saved state in the stack. This saves - some wasted effort since we won't need to look at the values. - - In particular, all caller-save registers are immediately available for - scratch use. - -*/ - -#define FRAME_SIZE (76*8 + 8) - - movi FRAME_SIZE, r0 - sub.l r15, r0, r15 - ! Do normal-style register save to support backtrace - - st.l r15, 0, r18 ! save link reg - st.l r15, 4, r14 ! save fp - add.l r15, r63, r14 ! setup frame pointer - - ! hopefully this looks normal to the backtrace now. - - addi.l r15, 8, r1 ! base of pt_regs - addi.l r1, 24, r0 ! base of pt_regs.regs - addi.l r0, (63*8), r8 ! base of pt_regs.trregs - - /* Note : to be fixed? - struct pt_regs is really designed for holding the state on entry - to an exception, i.e. pc,sr,regs etc. However, for the context - switch state, some of this is not required. But the unwinder takes - struct pt_regs * as an arg so we have to build this structure - to allow unwinding switched tasks in show_state() */ - - st.q r0, ( 9*8), r9 - st.q r0, (10*8), r10 - st.q r0, (11*8), r11 - st.q r0, (12*8), r12 - st.q r0, (13*8), r13 - st.q r0, (14*8), r14 ! for unwind, want to look as though we took a trap at - ! the point where the process is left in suspended animation, i.e. current - ! fp here, not the saved one. - st.q r0, (16*8), r16 - - st.q r0, (24*8), r24 - st.q r0, (25*8), r25 - st.q r0, (26*8), r26 - st.q r0, (27*8), r27 - st.q r0, (28*8), r28 - st.q r0, (29*8), r29 - st.q r0, (30*8), r30 - st.q r0, (31*8), r31 - st.q r0, (32*8), r32 - st.q r0, (33*8), r33 - st.q r0, (34*8), r34 - st.q r0, (35*8), r35 - - st.q r0, (44*8), r44 - st.q r0, (45*8), r45 - st.q r0, (46*8), r46 - st.q r0, (47*8), r47 - st.q r0, (48*8), r48 - st.q r0, (49*8), r49 - st.q r0, (50*8), r50 - st.q r0, (51*8), r51 - st.q r0, (52*8), r52 - st.q r0, (53*8), r53 - st.q r0, (54*8), r54 - st.q r0, (55*8), r55 - st.q r0, (56*8), r56 - st.q r0, (57*8), r57 - st.q r0, (58*8), r58 - st.q r0, (59*8), r59 - - ! do this early as pta->gettr has no pipeline forwarding (=> 5 cycle latency) - ! Use a local label to avoid creating a symbol that will confuse the ! - ! backtrace - pta .Lsave_pc, tr0 - - gettr tr5, r45 - gettr tr6, r46 - gettr tr7, r47 - st.q r8, (5*8), r45 - st.q r8, (6*8), r46 - st.q r8, (7*8), r47 - - ! Now switch context - gettr tr0, r9 - st.l r3, 0, r15 ! prev->thread.sp - st.l r3, 8, r1 ! prev->thread.kregs - st.l r3, 4, r9 ! prev->thread.pc - st.q r1, 0, r9 ! save prev->thread.pc into pt_regs->pc - - ! Load PC for next task (init value or save_pc later) - ld.l r5, 4, r18 ! next->thread.pc - ! Switch stacks - ld.l r5, 0, r15 ! next->thread.sp - ptabs r18, tr0 - - ! Update current - ld.l r4, 4, r9 ! next->thread_info (2nd element of next task_struct) - putcon r9, kcr0 ! current = next->thread_info - - ! go to save_pc for a reschedule, or the initial thread.pc for a new process - blink tr0, r63 - - ! Restore (when we come back to a previously saved task) -.Lsave_pc: - addi.l r15, 32, r0 ! r0 = next's regs - addi.l r0, (63*8), r8 ! r8 = next's tr_regs - - ld.q r8, (5*8), r45 - ld.q r8, (6*8), r46 - ld.q r8, (7*8), r47 - ptabs r45, tr5 - ptabs r46, tr6 - ptabs r47, tr7 - - ld.q r0, ( 9*8), r9 - ld.q r0, (10*8), r10 - ld.q r0, (11*8), r11 - ld.q r0, (12*8), r12 - ld.q r0, (13*8), r13 - ld.q r0, (14*8), r14 - ld.q r0, (16*8), r16 - - ld.q r0, (24*8), r24 - ld.q r0, (25*8), r25 - ld.q r0, (26*8), r26 - ld.q r0, (27*8), r27 - ld.q r0, (28*8), r28 - ld.q r0, (29*8), r29 - ld.q r0, (30*8), r30 - ld.q r0, (31*8), r31 - ld.q r0, (32*8), r32 - ld.q r0, (33*8), r33 - ld.q r0, (34*8), r34 - ld.q r0, (35*8), r35 - - ld.q r0, (44*8), r44 - ld.q r0, (45*8), r45 - ld.q r0, (46*8), r46 - ld.q r0, (47*8), r47 - ld.q r0, (48*8), r48 - ld.q r0, (49*8), r49 - ld.q r0, (50*8), r50 - ld.q r0, (51*8), r51 - ld.q r0, (52*8), r52 - ld.q r0, (53*8), r53 - ld.q r0, (54*8), r54 - ld.q r0, (55*8), r55 - ld.q r0, (56*8), r56 - ld.q r0, (57*8), r57 - ld.q r0, (58*8), r58 - ld.q r0, (59*8), r59 - - ! epilogue - ld.l r15, 0, r18 - ld.l r15, 4, r14 - ptabs r18, tr0 - movi FRAME_SIZE, r0 - add r15, r0, r15 - blink tr0, r63 -__sh64_switch_to_end: -.LFE1: - .size sh64_switch_to,.LFE1-sh64_switch_to - |