1/*
2 * etrap.S: Preparing for entry into the kernel on Sparc V9.
3 *
4 * Copyright (C) 1996, 1997 David S. Miller (davem@caip.rutgers.edu)
5 * Copyright (C) 1997, 1998, 1999 Jakub Jelinek (jj@ultra.linux.cz)
6 */
7
8
9#include <asm/asi.h>
10#include <asm/pstate.h>
11#include <asm/ptrace.h>
12#include <asm/page.h>
13#include <asm/spitfire.h>
14#include <asm/head.h>
15#include <asm/processor.h>
16#include <asm/mmu.h>
17
18#define		TASK_REGOFF		(THREAD_SIZE-TRACEREG_SZ-STACKFRAME_SZ)
19#define		ETRAP_PSTATE1		(PSTATE_TSO | PSTATE_PRIV)
20#define		ETRAP_PSTATE2		\
21		(PSTATE_TSO | PSTATE_PEF | PSTATE_PRIV | PSTATE_IE)
22
23/*
24 * On entry, %g7 is return address - 0x4.
25 * %g4 and %g5 will be preserved %l4 and %l5 respectively.
26 */
27
28		.text
29		.align	64
30		.globl	etrap_syscall, etrap, etrap_irq, etraptl1
31etrap:		rdpr	%pil, %g2
32etrap_irq:	clr	%g3
33etrap_syscall:	TRAP_LOAD_THREAD_REG(%g6, %g1)
34		rdpr	%tstate, %g1
35		or	%g1, %g3, %g1
36		sllx	%g2, 20, %g3
37		andcc	%g1, TSTATE_PRIV, %g0
38		or	%g1, %g3, %g1
39		bne,pn	%xcc, 1f
40		 sub	%sp, STACKFRAME_SZ+TRACEREG_SZ-STACK_BIAS, %g2
41		wrpr	%g0, 7, %cleanwin
42
43		sethi	%hi(TASK_REGOFF), %g2
44		sethi	%hi(TSTATE_PEF), %g3
45		or	%g2, %lo(TASK_REGOFF), %g2
46		and	%g1, %g3, %g3
47		brnz,pn	%g3, 1f
48		 add	%g6, %g2, %g2
49		wr	%g0, 0, %fprs
501:		rdpr	%tpc, %g3
51
52		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TSTATE]
53		rdpr	%tnpc, %g1
54		stx	%g3, [%g2 + STACKFRAME_SZ + PT_V9_TPC]
55		rd	%y, %g3
56		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TNPC]
57		rdpr	%tt, %g1
58		st	%g3, [%g2 + STACKFRAME_SZ + PT_V9_Y]
59		sethi	%hi(PT_REGS_MAGIC), %g3
60		or	%g3, %g1, %g1
61		st	%g1, [%g2 + STACKFRAME_SZ + PT_V9_MAGIC]
62
63		rdpr	%cansave, %g1
64		brnz,pt %g1, etrap_save
65		 nop
66
67		rdpr	%cwp, %g1
68		add	%g1, 2, %g1
69		wrpr	%g1, %cwp
70		be,pt	%xcc, etrap_user_spill
71		 mov	ASI_AIUP, %g3
72
73		rdpr	%otherwin, %g3
74		brz	%g3, etrap_kernel_spill
75		 mov	ASI_AIUS, %g3
76
77etrap_user_spill:
78
79		wr	%g3, 0x0, %asi
80		ldx	[%g6 + TI_FLAGS], %g3
81		and	%g3, _TIF_32BIT, %g3
82		brnz,pt	%g3, etrap_user_spill_32bit
83		 nop
84		ba,a,pt	%xcc, etrap_user_spill_64bit
85
86etrap_save:	save	%g2, -STACK_BIAS, %sp
87		mov	%g6, %l6
88
89		bne,pn	%xcc, 3f
90		 mov	PRIMARY_CONTEXT, %l4
91		rdpr	%canrestore, %g3
92		rdpr	%wstate, %g2
93		wrpr	%g0, 0, %canrestore
94		sll	%g2, 3, %g2
95		mov	1, %l5
96		stb	%l5, [%l6 + TI_FPDEPTH]
97
98		wrpr	%g3, 0, %otherwin
99		wrpr	%g2, 0, %wstate
100		sethi	%hi(sparc64_kern_pri_context), %g2
101		ldx	[%g2 + %lo(sparc64_kern_pri_context)], %g3
102
103661:		stxa	%g3, [%l4] ASI_DMMU
104		.section .sun4v_1insn_patch, "ax"
105		.word	661b
106		stxa	%g3, [%l4] ASI_MMU
107		.previous
108
109		sethi	%hi(KERNBASE), %l4
110		flush	%l4
111		mov	ASI_AIUS, %l7
1122:		mov	%g4, %l4
113		mov	%g5, %l5
114		add	%g7, 4, %l2
115
116		/* Go to trap time globals so we can save them.  */
117661:		wrpr	%g0, ETRAP_PSTATE1, %pstate
118		.section .sun4v_1insn_patch, "ax"
119		.word	661b
120		SET_GL(0)
121		.previous
122
123		stx	%g1, [%sp + PTREGS_OFF + PT_V9_G1]
124		stx	%g2, [%sp + PTREGS_OFF + PT_V9_G2]
125		sllx	%l7, 24, %l7
126		stx	%g3, [%sp + PTREGS_OFF + PT_V9_G3]
127		rdpr	%cwp, %l0
128		stx	%g4, [%sp + PTREGS_OFF + PT_V9_G4]
129		stx	%g5, [%sp + PTREGS_OFF + PT_V9_G5]
130		stx	%g6, [%sp + PTREGS_OFF + PT_V9_G6]
131		stx	%g7, [%sp + PTREGS_OFF + PT_V9_G7]
132		or	%l7, %l0, %l7
133		sethi	%hi(TSTATE_TSO | TSTATE_PEF), %l0
134		or	%l7, %l0, %l7
135		wrpr	%l2, %tnpc
136		wrpr	%l7, (TSTATE_PRIV | TSTATE_IE), %tstate
137		stx	%i0, [%sp + PTREGS_OFF + PT_V9_I0]
138		stx	%i1, [%sp + PTREGS_OFF + PT_V9_I1]
139		stx	%i2, [%sp + PTREGS_OFF + PT_V9_I2]
140		stx	%i3, [%sp + PTREGS_OFF + PT_V9_I3]
141		stx	%i4, [%sp + PTREGS_OFF + PT_V9_I4]
142		stx	%i5, [%sp + PTREGS_OFF + PT_V9_I5]
143		stx	%i6, [%sp + PTREGS_OFF + PT_V9_I6]
144		mov	%l6, %g6
145		stx	%i7, [%sp + PTREGS_OFF + PT_V9_I7]
146		LOAD_PER_CPU_BASE(%g5, %g6, %g4, %g3, %l1)
147		ldx	[%g6 + TI_TASK], %g4
148		done
149
1503:		mov	ASI_P, %l7
151		ldub	[%l6 + TI_FPDEPTH], %l5
152		add	%l6, TI_FPSAVED + 1, %l4
153		srl	%l5, 1, %l3
154		add	%l5, 2, %l5
155		stb	%l5, [%l6 + TI_FPDEPTH]
156		ba,pt	%xcc, 2b
157		 stb	%g0, [%l4 + %l3]
158		nop
159
160etraptl1:	/* Save tstate/tpc/tnpc of TL 1-->4 and the tl register itself.
161		 * We place this right after pt_regs on the trap stack.
162		 * The layout is:
163		 *	0x00	TL1's TSTATE
164		 *	0x08	TL1's TPC
165		 *	0x10	TL1's TNPC
166		 *	0x18	TL1's TT
167		 *	 ...
168		 *	0x58	TL4's TT
169		 *	0x60	TL
170		 */
171		TRAP_LOAD_THREAD_REG(%g6, %g1)
172		sub	%sp, ((4 * 8) * 4) + 8, %g2
173		rdpr	%tl, %g1
174
175		wrpr	%g0, 1, %tl
176		rdpr	%tstate, %g3
177		stx	%g3, [%g2 + STACK_BIAS + 0x00]
178		rdpr	%tpc, %g3
179		stx	%g3, [%g2 + STACK_BIAS + 0x08]
180		rdpr	%tnpc, %g3
181		stx	%g3, [%g2 + STACK_BIAS + 0x10]
182		rdpr	%tt, %g3
183		stx	%g3, [%g2 + STACK_BIAS + 0x18]
184
185		wrpr	%g0, 2, %tl
186		rdpr	%tstate, %g3
187		stx	%g3, [%g2 + STACK_BIAS + 0x20]
188		rdpr	%tpc, %g3
189		stx	%g3, [%g2 + STACK_BIAS + 0x28]
190		rdpr	%tnpc, %g3
191		stx	%g3, [%g2 + STACK_BIAS + 0x30]
192		rdpr	%tt, %g3
193		stx	%g3, [%g2 + STACK_BIAS + 0x38]
194
195		sethi	%hi(is_sun4v), %g3
196		lduw	[%g3 + %lo(is_sun4v)], %g3
197		brnz,pn	%g3, finish_tl1_capture
198		 nop
199
200		wrpr	%g0, 3, %tl
201		rdpr	%tstate, %g3
202		stx	%g3, [%g2 + STACK_BIAS + 0x40]
203		rdpr	%tpc, %g3
204		stx	%g3, [%g2 + STACK_BIAS + 0x48]
205		rdpr	%tnpc, %g3
206		stx	%g3, [%g2 + STACK_BIAS + 0x50]
207		rdpr	%tt, %g3
208		stx	%g3, [%g2 + STACK_BIAS + 0x58]
209
210		wrpr	%g0, 4, %tl
211		rdpr	%tstate, %g3
212		stx	%g3, [%g2 + STACK_BIAS + 0x60]
213		rdpr	%tpc, %g3
214		stx	%g3, [%g2 + STACK_BIAS + 0x68]
215		rdpr	%tnpc, %g3
216		stx	%g3, [%g2 + STACK_BIAS + 0x70]
217		rdpr	%tt, %g3
218		stx	%g3, [%g2 + STACK_BIAS + 0x78]
219
220		stx	%g1, [%g2 + STACK_BIAS + 0x80]
221
222finish_tl1_capture:
223		wrpr	%g0, 1, %tl
224661:		nop
225		.section .sun4v_1insn_patch, "ax"
226		.word	661b
227		SET_GL(1)
228		.previous
229
230		rdpr	%tstate, %g1
231		sub	%g2, STACKFRAME_SZ + TRACEREG_SZ - STACK_BIAS, %g2
232		ba,pt	%xcc, 1b
233		 andcc	%g1, TSTATE_PRIV, %g0
234
235#undef TASK_REGOFF
236#undef ETRAP_PSTATE1
237