Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / arch / powerpc / platforms / iseries / exception.S
1 /*
2  *  Low level routines for legacy iSeries support.
3  *
4  *  Extracted from head_64.S
5  *
6  *  PowerPC version
7  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
8  *
9  *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
10  *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
11  *  Adapted for Power Macintosh by Paul Mackerras.
12  *  Low-level exception handlers and MMU support
13  *  rewritten by Paul Mackerras.
14  *    Copyright (C) 1996 Paul Mackerras.
15  *
16  *  Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
17  *    Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
18  *
19  *  This file contains the low-level support and setup for the
20  *  PowerPC-64 platform, including trap and interrupt dispatch.
21  *
22  *  This program is free software; you can redistribute it and/or
23  *  modify it under the terms of the GNU General Public License
24  *  as published by the Free Software Foundation; either version
25  *  2 of the License, or (at your option) any later version.
26  */
27
28 #include <asm/reg.h>
29 #include <asm/ppc_asm.h>
30 #include <asm/asm-offsets.h>
31 #include <asm/thread_info.h>
32 #include <asm/ptrace.h>
33 #include <asm/cputable.h>
34
35 #include "exception.h"
36
37         .text
38
39         .globl system_reset_iSeries
40 system_reset_iSeries:
41         mfspr   r13,SPRN_SPRG3          /* Get alpaca address */
42         LOAD_REG_IMMEDIATE(r23, alpaca)
43         li      r0,ALPACA_SIZE
44         sub     r23,r13,r23
45         divdu   r23,r23,r0              /* r23 has cpu number */
46         LOAD_REG_IMMEDIATE(r13, paca)
47         mulli   r0,r23,PACA_SIZE
48         add     r13,r13,r0
49         mtspr   SPRN_SPRG3,r13          /* Save it away for the future */
50         mfmsr   r24
51         ori     r24,r24,MSR_RI
52         mtmsrd  r24                     /* RI on */
53         mr      r24,r23
54         cmpwi   0,r24,0                 /* Are we processor 0? */
55         bne     1f
56         b       .__start_initialization_iSeries /* Start up the first processor */
57 1:      mfspr   r4,SPRN_CTRLF
58         li      r5,CTRL_RUNLATCH        /* Turn off the run light */
59         andc    r4,r4,r5
60         mtspr   SPRN_CTRLT,r4
61
62 1:
63         HMT_LOW
64 #ifdef CONFIG_SMP
65         lbz     r23,PACAPROCSTART(r13)  /* Test if this processor
66                                          * should start */
67         sync
68         LOAD_REG_IMMEDIATE(r3,current_set)
69         sldi    r28,r24,3               /* get current_set[cpu#] */
70         ldx     r3,r3,r28
71         addi    r1,r3,THREAD_SIZE
72         subi    r1,r1,STACK_FRAME_OVERHEAD
73
74         cmpwi   0,r23,0
75         beq     iSeries_secondary_smp_loop      /* Loop until told to go */
76         b       __secondary_start               /* Loop until told to go */
77 iSeries_secondary_smp_loop:
78         /* Let the Hypervisor know we are alive */
79         /* 8002 is a call to HvCallCfg::getLps, a harmless Hypervisor function */
80         lis     r3,0x8002
81         rldicr  r3,r3,32,15             /* r0 = (r3 << 32) & 0xffff000000000000 */
82 #else /* CONFIG_SMP */
83         /* Yield the processor.  This is required for non-SMP kernels
84                 which are running on multi-threaded machines. */
85         lis     r3,0x8000
86         rldicr  r3,r3,32,15             /* r3 = (r3 << 32) & 0xffff000000000000 */
87         addi    r3,r3,18                /* r3 = 0x8000000000000012 which is "yield" */
88         li      r4,0                    /* "yield timed" */
89         li      r5,-1                   /* "yield forever" */
90 #endif /* CONFIG_SMP */
91         li      r0,-1                   /* r0=-1 indicates a Hypervisor call */
92         sc                              /* Invoke the hypervisor via a system call */
93         mfspr   r13,SPRN_SPRG3          /* Put r13 back ???? */
94         b       1b                      /* If SMP not configured, secondaries
95                                          * loop forever */
96
97 /***  ISeries-LPAR interrupt handlers ***/
98
99         STD_EXCEPTION_ISERIES(machine_check, PACA_EXMC)
100
101         .globl data_access_iSeries
102 data_access_iSeries:
103         mtspr   SPRN_SPRG1,r13
104 BEGIN_FTR_SECTION
105         mtspr   SPRN_SPRG2,r12
106         mfspr   r13,SPRN_DAR
107         mfspr   r12,SPRN_DSISR
108         srdi    r13,r13,60
109         rlwimi  r13,r12,16,0x20
110         mfcr    r12
111         cmpwi   r13,0x2c
112         beq     .do_stab_bolted_iSeries
113         mtcrf   0x80,r12
114         mfspr   r12,SPRN_SPRG2
115 END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
116         EXCEPTION_PROLOG_1(PACA_EXGEN)
117         EXCEPTION_PROLOG_ISERIES_1
118         b       data_access_common
119
120 .do_stab_bolted_iSeries:
121         mtcrf   0x80,r12
122         mfspr   r12,SPRN_SPRG2
123         EXCEPTION_PROLOG_1(PACA_EXSLB)
124         EXCEPTION_PROLOG_ISERIES_1
125         b       .do_stab_bolted
126
127         .globl  data_access_slb_iSeries
128 data_access_slb_iSeries:
129         mtspr   SPRN_SPRG1,r13          /* save r13 */
130         mfspr   r13,SPRN_SPRG3          /* get paca address into r13 */
131         std     r3,PACA_EXSLB+EX_R3(r13)
132         mfspr   r3,SPRN_DAR
133         std     r9,PACA_EXSLB+EX_R9(r13)
134         mfcr    r9
135 #ifdef __DISABLED__
136         cmpdi   r3,0
137         bge     slb_miss_user_iseries
138 #endif
139         std     r10,PACA_EXSLB+EX_R10(r13)
140         std     r11,PACA_EXSLB+EX_R11(r13)
141         std     r12,PACA_EXSLB+EX_R12(r13)
142         mfspr   r10,SPRN_SPRG1
143         std     r10,PACA_EXSLB+EX_R13(r13)
144         ld      r12,PACALPPACAPTR(r13)
145         ld      r12,LPPACASRR1(r12)
146         b       .slb_miss_realmode
147
148         STD_EXCEPTION_ISERIES(instruction_access, PACA_EXGEN)
149
150         .globl  instruction_access_slb_iSeries
151 instruction_access_slb_iSeries:
152         mtspr   SPRN_SPRG1,r13          /* save r13 */
153         mfspr   r13,SPRN_SPRG3          /* get paca address into r13 */
154         std     r3,PACA_EXSLB+EX_R3(r13)
155         ld      r3,PACALPPACAPTR(r13)
156         ld      r3,LPPACASRR0(r3)       /* get SRR0 value */
157         std     r9,PACA_EXSLB+EX_R9(r13)
158         mfcr    r9
159 #ifdef __DISABLED__
160         cmpdi   r3,0
161         bge     slb_miss_user_iseries
162 #endif
163         std     r10,PACA_EXSLB+EX_R10(r13)
164         std     r11,PACA_EXSLB+EX_R11(r13)
165         std     r12,PACA_EXSLB+EX_R12(r13)
166         mfspr   r10,SPRN_SPRG1
167         std     r10,PACA_EXSLB+EX_R13(r13)
168         ld      r12,PACALPPACAPTR(r13)
169         ld      r12,LPPACASRR1(r12)
170         b       .slb_miss_realmode
171
172 #ifdef __DISABLED__
173 slb_miss_user_iseries:
174         std     r10,PACA_EXGEN+EX_R10(r13)
175         std     r11,PACA_EXGEN+EX_R11(r13)
176         std     r12,PACA_EXGEN+EX_R12(r13)
177         mfspr   r10,SPRG1
178         ld      r11,PACA_EXSLB+EX_R9(r13)
179         ld      r12,PACA_EXSLB+EX_R3(r13)
180         std     r10,PACA_EXGEN+EX_R13(r13)
181         std     r11,PACA_EXGEN+EX_R9(r13)
182         std     r12,PACA_EXGEN+EX_R3(r13)
183         EXCEPTION_PROLOG_ISERIES_1
184         b       slb_miss_user_common
185 #endif
186
187         MASKABLE_EXCEPTION_ISERIES(hardware_interrupt)
188         STD_EXCEPTION_ISERIES(alignment, PACA_EXGEN)
189         STD_EXCEPTION_ISERIES(program_check, PACA_EXGEN)
190         STD_EXCEPTION_ISERIES(fp_unavailable, PACA_EXGEN)
191         MASKABLE_EXCEPTION_ISERIES(decrementer)
192         STD_EXCEPTION_ISERIES(trap_0a, PACA_EXGEN)
193         STD_EXCEPTION_ISERIES(trap_0b, PACA_EXGEN)
194
195         .globl  system_call_iSeries
196 system_call_iSeries:
197         mr      r9,r13
198         mfspr   r13,SPRN_SPRG3
199         EXCEPTION_PROLOG_ISERIES_1
200         b       system_call_common
201
202         STD_EXCEPTION_ISERIES(single_step, PACA_EXGEN)
203         STD_EXCEPTION_ISERIES(trap_0e, PACA_EXGEN)
204         STD_EXCEPTION_ISERIES(performance_monitor, PACA_EXGEN)
205
206 decrementer_iSeries_masked:
207         /* We may not have a valid TOC pointer in here. */
208         li      r11,1
209         ld      r12,PACALPPACAPTR(r13)
210         stb     r11,LPPACADECRINT(r12)
211         LOAD_REG_IMMEDIATE(r12, tb_ticks_per_jiffy)
212         lwz     r12,0(r12)
213         mtspr   SPRN_DEC,r12
214         /* fall through */
215
216 hardware_interrupt_iSeries_masked:
217         mtcrf   0x80,r9         /* Restore regs */
218         ld      r12,PACALPPACAPTR(r13)
219         ld      r11,LPPACASRR0(r12)
220         ld      r12,LPPACASRR1(r12)
221         mtspr   SPRN_SRR0,r11
222         mtspr   SPRN_SRR1,r12
223         ld      r9,PACA_EXGEN+EX_R9(r13)
224         ld      r10,PACA_EXGEN+EX_R10(r13)
225         ld      r11,PACA_EXGEN+EX_R11(r13)
226         ld      r12,PACA_EXGEN+EX_R12(r13)
227         ld      r13,PACA_EXGEN+EX_R13(r13)
228         rfid
229         b       .       /* prevent speculative execution */
230
231 _INIT_STATIC(__start_initialization_iSeries)
232         /* Clear out the BSS */
233         LOAD_REG_IMMEDIATE(r11,__bss_stop)
234         LOAD_REG_IMMEDIATE(r8,__bss_start)
235         sub     r11,r11,r8              /* bss size                     */
236         addi    r11,r11,7               /* round up to an even double word */
237         rldicl. r11,r11,61,3            /* shift right by 3             */
238         beq     4f
239         addi    r8,r8,-8
240         li      r0,0
241         mtctr   r11                     /* zero this many doublewords   */
242 3:      stdu    r0,8(r8)
243         bdnz    3b
244 4:
245         LOAD_REG_IMMEDIATE(r1,init_thread_union)
246         addi    r1,r1,THREAD_SIZE
247         li      r0,0
248         stdu    r0,-STACK_FRAME_OVERHEAD(r1)
249
250         LOAD_REG_IMMEDIATE(r2,__toc_start)
251         addi    r2,r2,0x4000
252         addi    r2,r2,0x4000
253
254         bl      .iSeries_early_setup
255         bl      .early_setup
256
257         /* relocation is on at this point */
258
259         b       .start_here_common