|  | /* $Id: rtrap.S,v 1.61 2002/02/09 19:49:31 davem Exp $ | 
|  | * rtrap.S: Preparing for return from trap on Sparc V9. | 
|  | * | 
|  | * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) | 
|  | * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu) | 
|  | */ | 
|  |  | 
|  |  | 
|  | #include <asm/asi.h> | 
|  | #include <asm/pstate.h> | 
|  | #include <asm/ptrace.h> | 
|  | #include <asm/spitfire.h> | 
|  | #include <asm/head.h> | 
|  | #include <asm/visasm.h> | 
|  | #include <asm/processor.h> | 
|  |  | 
|  | #define		RTRAP_PSTATE		(PSTATE_RMO|PSTATE_PEF|PSTATE_PRIV|PSTATE_IE) | 
|  | #define		RTRAP_PSTATE_IRQOFF	(PSTATE_RMO|PSTATE_PEF|PSTATE_PRIV) | 
|  | #define		RTRAP_PSTATE_AG_IRQOFF	(PSTATE_RMO|PSTATE_PEF|PSTATE_PRIV|PSTATE_AG) | 
|  |  | 
|  | /* Register %l6 keeps track of whether we are returning | 
|  | * from a system call or not.  It is cleared if we call | 
|  | * do_notify_resume, and it must not be otherwise modified | 
|  | * until we fully commit to returning to userspace. | 
|  | */ | 
|  |  | 
|  | .text | 
|  | .align			32 | 
|  | __handle_softirq: | 
|  | call			do_softirq | 
|  | nop | 
|  | ba,a,pt			%xcc, __handle_softirq_continue | 
|  | nop | 
|  | __handle_preemption: | 
|  | call			schedule | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | ba,pt			%xcc, __handle_preemption_continue | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  |  | 
|  | __handle_user_windows: | 
|  | call			fault_in_user_windows | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | /* Redo sched+sig checks */ | 
|  | ldx			[%g6 + TI_FLAGS], %l0 | 
|  | andcc			%l0, _TIF_NEED_RESCHED, %g0 | 
|  |  | 
|  | be,pt			%xcc, 1f | 
|  | nop | 
|  | call			schedule | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | ldx			[%g6 + TI_FLAGS], %l0 | 
|  |  | 
|  | 1:		andcc			%l0, (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), %g0 | 
|  | be,pt			%xcc, __handle_user_windows_continue | 
|  | nop | 
|  | mov			%l5, %o1 | 
|  | mov			%l6, %o2 | 
|  | add			%sp, PTREGS_OFF, %o0 | 
|  | mov			%l0, %o3 | 
|  |  | 
|  | call			do_notify_resume | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | clr			%l6 | 
|  | /* Signal delivery can modify pt_regs tstate, so we must | 
|  | * reload it. | 
|  | */ | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TSTATE], %l1 | 
|  | sethi			%hi(0xf << 20), %l4 | 
|  | and			%l1, %l4, %l4 | 
|  | ba,pt			%xcc, __handle_user_windows_continue | 
|  |  | 
|  | andn			%l1, %l4, %l1 | 
|  | __handle_perfctrs: | 
|  | call			update_perfctrs | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | ldub			[%g6 + TI_WSAVED], %o2 | 
|  | brz,pt			%o2, 1f | 
|  | nop | 
|  | /* Redo userwin+sched+sig checks */ | 
|  | call			fault_in_user_windows | 
|  |  | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | ldx			[%g6 + TI_FLAGS], %l0 | 
|  | andcc			%l0, _TIF_NEED_RESCHED, %g0 | 
|  | be,pt			%xcc, 1f | 
|  |  | 
|  | nop | 
|  | call			schedule | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | ldx			[%g6 + TI_FLAGS], %l0 | 
|  | 1:		andcc			%l0, (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), %g0 | 
|  |  | 
|  | be,pt			%xcc, __handle_perfctrs_continue | 
|  | sethi			%hi(TSTATE_PEF), %o0 | 
|  | mov			%l5, %o1 | 
|  | mov			%l6, %o2 | 
|  | add			%sp, PTREGS_OFF, %o0 | 
|  | mov			%l0, %o3 | 
|  | call			do_notify_resume | 
|  |  | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | clr			%l6 | 
|  | /* Signal delivery can modify pt_regs tstate, so we must | 
|  | * reload it. | 
|  | */ | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TSTATE], %l1 | 
|  | sethi			%hi(0xf << 20), %l4 | 
|  | and			%l1, %l4, %l4 | 
|  | andn			%l1, %l4, %l1 | 
|  | ba,pt			%xcc, __handle_perfctrs_continue | 
|  |  | 
|  | sethi			%hi(TSTATE_PEF), %o0 | 
|  | __handle_userfpu: | 
|  | rd			%fprs, %l5 | 
|  | andcc			%l5, FPRS_FEF, %g0 | 
|  | sethi			%hi(TSTATE_PEF), %o0 | 
|  | be,a,pn			%icc, __handle_userfpu_continue | 
|  | andn			%l1, %o0, %l1 | 
|  | ba,a,pt			%xcc, __handle_userfpu_continue | 
|  |  | 
|  | __handle_signal: | 
|  | mov			%l5, %o1 | 
|  | mov			%l6, %o2 | 
|  | add			%sp, PTREGS_OFF, %o0 | 
|  | mov			%l0, %o3 | 
|  | call			do_notify_resume | 
|  | wrpr			%g0, RTRAP_PSTATE, %pstate | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | clr			%l6 | 
|  |  | 
|  | /* Signal delivery can modify pt_regs tstate, so we must | 
|  | * reload it. | 
|  | */ | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TSTATE], %l1 | 
|  | sethi			%hi(0xf << 20), %l4 | 
|  | and			%l1, %l4, %l4 | 
|  | ba,pt			%xcc, __handle_signal_continue | 
|  | andn			%l1, %l4, %l1 | 
|  |  | 
|  | .align			64 | 
|  | .globl			rtrap_irq, rtrap_clr_l6, rtrap, irqsz_patchme, rtrap_xcall | 
|  | rtrap_irq: | 
|  | rtrap_clr_l6:	clr			%l6 | 
|  | rtrap: | 
|  | #ifndef CONFIG_SMP | 
|  | sethi			%hi(per_cpu____cpu_data), %l0 | 
|  | lduw			[%l0 + %lo(per_cpu____cpu_data)], %l1 | 
|  | #else | 
|  | sethi			%hi(per_cpu____cpu_data), %l0 | 
|  | or			%l0, %lo(per_cpu____cpu_data), %l0 | 
|  | lduw			[%l0 + %g5], %l1 | 
|  | #endif | 
|  | cmp			%l1, 0 | 
|  |  | 
|  | /* mm/ultra.S:xcall_report_regs KNOWS about this load. */ | 
|  | bne,pn			%icc, __handle_softirq | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TSTATE], %l1 | 
|  | __handle_softirq_continue: | 
|  | rtrap_xcall: | 
|  | sethi			%hi(0xf << 20), %l4 | 
|  | andcc			%l1, TSTATE_PRIV, %l3 | 
|  | and			%l1, %l4, %l4 | 
|  | bne,pn			%icc, to_kernel | 
|  | andn			%l1, %l4, %l1 | 
|  |  | 
|  | /* We must hold IRQs off and atomically test schedule+signal | 
|  | * state, then hold them off all the way back to userspace. | 
|  | * If we are returning to kernel, none of this matters. | 
|  | * | 
|  | * If we do not do this, there is a window where we would do | 
|  | * the tests, later the signal/resched event arrives but we do | 
|  | * not process it since we are still in kernel mode.  It would | 
|  | * take until the next local IRQ before the signal/resched | 
|  | * event would be handled. | 
|  | * | 
|  | * This also means that if we have to deal with performance | 
|  | * counters or user windows, we have to redo all of these | 
|  | * sched+signal checks with IRQs disabled. | 
|  | */ | 
|  | to_user:	wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | wrpr			0, %pil | 
|  | __handle_preemption_continue: | 
|  | ldx			[%g6 + TI_FLAGS], %l0 | 
|  | sethi			%hi(_TIF_USER_WORK_MASK), %o0 | 
|  | or			%o0, %lo(_TIF_USER_WORK_MASK), %o0 | 
|  | andcc			%l0, %o0, %g0 | 
|  | sethi			%hi(TSTATE_PEF), %o0 | 
|  | be,pt			%xcc, user_nowork | 
|  | andcc			%l1, %o0, %g0 | 
|  | andcc			%l0, _TIF_NEED_RESCHED, %g0 | 
|  | bne,pn			%xcc, __handle_preemption | 
|  | andcc			%l0, (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), %g0 | 
|  | bne,pn			%xcc, __handle_signal | 
|  | __handle_signal_continue: | 
|  | ldub			[%g6 + TI_WSAVED], %o2 | 
|  | brnz,pn			%o2, __handle_user_windows | 
|  | nop | 
|  | __handle_user_windows_continue: | 
|  | ldx			[%g6 + TI_FLAGS], %l5 | 
|  | andcc			%l5, _TIF_PERFCTR, %g0 | 
|  | sethi			%hi(TSTATE_PEF), %o0 | 
|  | bne,pn			%xcc, __handle_perfctrs | 
|  | __handle_perfctrs_continue: | 
|  | andcc			%l1, %o0, %g0 | 
|  |  | 
|  | /* This fpdepth clear is necessary for non-syscall rtraps only */ | 
|  | user_nowork: | 
|  | bne,pn			%xcc, __handle_userfpu | 
|  | stb			%g0, [%g6 + TI_FPDEPTH] | 
|  | __handle_userfpu_continue: | 
|  |  | 
|  | rt_continue:	ldx			[%sp + PTREGS_OFF + PT_V9_G1], %g1 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G2], %g2 | 
|  |  | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G3], %g3 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G4], %g4 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G5], %g5 | 
|  | brz,pt			%l3, 1f | 
|  | mov			%g6, %l2 | 
|  |  | 
|  | /* Must do this before thread reg is clobbered below.  */ | 
|  | LOAD_PER_CPU_BASE(%g5, %g6, %i0, %i1, %i2) | 
|  | 1: | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G6], %g6 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_G7], %g7 | 
|  |  | 
|  | /* Normal globals are restored, go to trap globals.  */ | 
|  | 661:		wrpr			%g0, RTRAP_PSTATE_AG_IRQOFF, %pstate | 
|  | nop | 
|  | .section		.sun4v_2insn_patch, "ax" | 
|  | .word			661b | 
|  | wrpr			%g0, RTRAP_PSTATE_IRQOFF, %pstate | 
|  | SET_GL(1) | 
|  | .previous | 
|  |  | 
|  | mov			%l2, %g6 | 
|  |  | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I0], %i0 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I1], %i1 | 
|  |  | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I2], %i2 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I3], %i3 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I4], %i4 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I5], %i5 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I6], %i6 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_I7], %i7 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TPC], %l2 | 
|  | ldx			[%sp + PTREGS_OFF + PT_V9_TNPC], %o2 | 
|  |  | 
|  | ld			[%sp + PTREGS_OFF + PT_V9_Y], %o3 | 
|  | wr			%o3, %g0, %y | 
|  | srl			%l4, 20, %l4 | 
|  | wrpr			%l4, 0x0, %pil | 
|  | wrpr			%g0, 0x1, %tl | 
|  | wrpr			%l1, %g0, %tstate | 
|  | wrpr			%l2, %g0, %tpc | 
|  | wrpr			%o2, %g0, %tnpc | 
|  |  | 
|  | brnz,pn			%l3, kern_rtt | 
|  | mov			PRIMARY_CONTEXT, %l7 | 
|  |  | 
|  | 661:		ldxa			[%l7 + %l7] ASI_DMMU, %l0 | 
|  | .section		.sun4v_1insn_patch, "ax" | 
|  | .word			661b | 
|  | ldxa			[%l7 + %l7] ASI_MMU, %l0 | 
|  | .previous | 
|  |  | 
|  | sethi			%hi(sparc64_kern_pri_nuc_bits), %l1 | 
|  | ldx			[%l1 + %lo(sparc64_kern_pri_nuc_bits)], %l1 | 
|  | or			%l0, %l1, %l0 | 
|  |  | 
|  | 661:		stxa			%l0, [%l7] ASI_DMMU | 
|  | .section		.sun4v_1insn_patch, "ax" | 
|  | .word			661b | 
|  | stxa			%l0, [%l7] ASI_MMU | 
|  | .previous | 
|  |  | 
|  | sethi			%hi(KERNBASE), %l7 | 
|  | flush			%l7 | 
|  | rdpr			%wstate, %l1 | 
|  | rdpr			%otherwin, %l2 | 
|  | srl			%l1, 3, %l1 | 
|  |  | 
|  | wrpr			%l2, %g0, %canrestore | 
|  | wrpr			%l1, %g0, %wstate | 
|  | brnz,pt			%l2, user_rtt_restore | 
|  | wrpr			%g0, %g0, %otherwin | 
|  |  | 
|  | ldx			[%g6 + TI_FLAGS], %g3 | 
|  | wr			%g0, ASI_AIUP, %asi | 
|  | rdpr			%cwp, %g1 | 
|  | andcc			%g3, _TIF_32BIT, %g0 | 
|  | sub			%g1, 1, %g1 | 
|  | bne,pt			%xcc, user_rtt_fill_32bit | 
|  | wrpr			%g1, %cwp | 
|  | ba,a,pt			%xcc, user_rtt_fill_64bit | 
|  |  | 
|  | user_rtt_fill_fixup: | 
|  | rdpr	%cwp, %g1 | 
|  | add	%g1, 1, %g1 | 
|  | wrpr	%g1, 0x0, %cwp | 
|  |  | 
|  | rdpr	%wstate, %g2 | 
|  | sll	%g2, 3, %g2 | 
|  | wrpr	%g2, 0x0, %wstate | 
|  |  | 
|  | /* We know %canrestore and %otherwin are both zero.  */ | 
|  |  | 
|  | sethi	%hi(sparc64_kern_pri_context), %g2 | 
|  | ldx	[%g2 + %lo(sparc64_kern_pri_context)], %g2 | 
|  | mov	PRIMARY_CONTEXT, %g1 | 
|  |  | 
|  | 661:		stxa	%g2, [%g1] ASI_DMMU | 
|  | .section .sun4v_1insn_patch, "ax" | 
|  | .word	661b | 
|  | stxa	%g2, [%g1] ASI_MMU | 
|  | .previous | 
|  |  | 
|  | sethi	%hi(KERNBASE), %g1 | 
|  | flush	%g1 | 
|  |  | 
|  | or	%g4, FAULT_CODE_WINFIXUP, %g4 | 
|  | stb	%g4, [%g6 + TI_FAULT_CODE] | 
|  | stx	%g5, [%g6 + TI_FAULT_ADDR] | 
|  |  | 
|  | mov	%g6, %l1 | 
|  | wrpr	%g0, 0x0, %tl | 
|  |  | 
|  | 661:		nop | 
|  | .section		.sun4v_1insn_patch, "ax" | 
|  | .word			661b | 
|  | SET_GL(0) | 
|  | .previous | 
|  |  | 
|  | wrpr	%g0, RTRAP_PSTATE, %pstate | 
|  |  | 
|  | mov	%l1, %g6 | 
|  | ldx	[%g6 + TI_TASK], %g4 | 
|  | LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3) | 
|  | call	do_sparc64_fault | 
|  | add	%sp, PTREGS_OFF, %o0 | 
|  | ba,pt	%xcc, rtrap | 
|  | nop | 
|  |  | 
|  | user_rtt_pre_restore: | 
|  | add			%g1, 1, %g1 | 
|  | wrpr			%g1, 0x0, %cwp | 
|  |  | 
|  | user_rtt_restore: | 
|  | restore | 
|  | rdpr			%canrestore, %g1 | 
|  | wrpr			%g1, 0x0, %cleanwin | 
|  | retry | 
|  | nop | 
|  |  | 
|  | kern_rtt:	rdpr			%canrestore, %g1 | 
|  | brz,pn			%g1, kern_rtt_fill | 
|  | nop | 
|  | kern_rtt_restore: | 
|  | restore | 
|  | retry | 
|  |  | 
|  | to_kernel: | 
|  | #ifdef CONFIG_PREEMPT | 
|  | ldsw			[%g6 + TI_PRE_COUNT], %l5 | 
|  | brnz			%l5, kern_fpucheck | 
|  | ldx			[%g6 + TI_FLAGS], %l5 | 
|  | andcc			%l5, _TIF_NEED_RESCHED, %g0 | 
|  | be,pt			%xcc, kern_fpucheck | 
|  | srl			%l4, 20, %l5 | 
|  | cmp			%l5, 0 | 
|  | bne,pn			%xcc, kern_fpucheck | 
|  | sethi			%hi(PREEMPT_ACTIVE), %l6 | 
|  | stw			%l6, [%g6 + TI_PRE_COUNT] | 
|  | call			schedule | 
|  | nop | 
|  | ba,pt			%xcc, rtrap | 
|  | stw			%g0, [%g6 + TI_PRE_COUNT] | 
|  | #endif | 
|  | kern_fpucheck:	ldub			[%g6 + TI_FPDEPTH], %l5 | 
|  | brz,pt			%l5, rt_continue | 
|  | srl			%l5, 1, %o0 | 
|  | add			%g6, TI_FPSAVED, %l6 | 
|  | ldub			[%l6 + %o0], %l2 | 
|  | sub			%l5, 2, %l5 | 
|  |  | 
|  | add			%g6, TI_GSR, %o1 | 
|  | andcc			%l2, (FPRS_FEF|FPRS_DU), %g0 | 
|  | be,pt			%icc, 2f | 
|  | and			%l2, FPRS_DL, %l6 | 
|  | andcc			%l2, FPRS_FEF, %g0 | 
|  | be,pn			%icc, 5f | 
|  | sll			%o0, 3, %o5 | 
|  | rd			%fprs, %g1 | 
|  |  | 
|  | wr			%g1, FPRS_FEF, %fprs | 
|  | ldx			[%o1 + %o5], %g1 | 
|  | add			%g6, TI_XFSR, %o1 | 
|  | sll			%o0, 8, %o2 | 
|  | add			%g6, TI_FPREGS, %o3 | 
|  | brz,pn			%l6, 1f | 
|  | add			%g6, TI_FPREGS+0x40, %o4 | 
|  |  | 
|  | membar			#Sync | 
|  | ldda			[%o3 + %o2] ASI_BLK_P, %f0 | 
|  | ldda			[%o4 + %o2] ASI_BLK_P, %f16 | 
|  | membar			#Sync | 
|  | 1:		andcc			%l2, FPRS_DU, %g0 | 
|  | be,pn			%icc, 1f | 
|  | wr			%g1, 0, %gsr | 
|  | add			%o2, 0x80, %o2 | 
|  | membar			#Sync | 
|  | ldda			[%o3 + %o2] ASI_BLK_P, %f32 | 
|  | ldda			[%o4 + %o2] ASI_BLK_P, %f48 | 
|  | 1:		membar			#Sync | 
|  | ldx			[%o1 + %o5], %fsr | 
|  | 2:		stb			%l5, [%g6 + TI_FPDEPTH] | 
|  | ba,pt			%xcc, rt_continue | 
|  | nop | 
|  | 5:		wr			%g0, FPRS_FEF, %fprs | 
|  | sll			%o0, 8, %o2 | 
|  |  | 
|  | add			%g6, TI_FPREGS+0x80, %o3 | 
|  | add			%g6, TI_FPREGS+0xc0, %o4 | 
|  | membar			#Sync | 
|  | ldda			[%o3 + %o2] ASI_BLK_P, %f32 | 
|  | ldda			[%o4 + %o2] ASI_BLK_P, %f48 | 
|  | membar			#Sync | 
|  | wr			%g0, FPRS_DU, %fprs | 
|  | ba,pt			%xcc, rt_continue | 
|  | stb			%l5, [%g6 + TI_FPDEPTH] |