tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * This file contains low level CPU setup functions.
3 * Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
9 *
10 */
11
12#include <asm/processor.h>
13#include <asm/page.h>
14#include <asm/cputable.h>
15#include <asm/ppc_asm.h>
16#include <asm/asm-offsets.h>
17#include <asm/cache.h>
18
19_GLOBAL(__970_cpu_preinit)
20 /*
21 * Do nothing if not running in HV mode
22 */
23 mfmsr r0
24 rldicl. r0,r0,4,63
25 beqlr
26
27 /*
28 * Deal only with PPC970 and PPC970FX.
29 */
30 mfspr r0,SPRN_PVR
31 srwi r0,r0,16
32 cmpwi r0,0x39
33 beq 1f
34 cmpwi r0,0x3c
35 beq 1f
36 cmpwi r0,0x44
37 bnelr
381:
39
40 /* Make sure HID4:rm_ci is off before MMU is turned off, that large
41 * pages are enabled with HID4:61 and clear HID5:DCBZ_size and
42 * HID5:DCBZ32_ill
43 */
44 li r0,0
45 mfspr r3,SPRN_HID4
46 rldimi r3,r0,40,23 /* clear bit 23 (rm_ci) */
47 rldimi r3,r0,2,61 /* clear bit 61 (lg_pg_en) */
48 sync
49 mtspr SPRN_HID4,r3
50 isync
51 sync
52 mfspr r3,SPRN_HID5
53 rldimi r3,r0,6,56 /* clear bits 56 & 57 (DCBZ*) */
54 sync
55 mtspr SPRN_HID5,r3
56 isync
57 sync
58
59 /* Setup some basic HID1 features */
60 mfspr r0,SPRN_HID1
61 li r3,0x1200 /* enable i-fetch cacheability */
62 sldi r3,r3,44 /* and prefetch */
63 or r0,r0,r3
64 mtspr SPRN_HID1,r0
65 mtspr SPRN_HID1,r0
66 isync
67
68 /* Clear HIOR */
69 li r0,0
70 sync
71 mtspr SPRN_HIOR,0 /* Clear interrupt prefix */
72 isync
73 blr
74
75_GLOBAL(__setup_cpu_ppc970)
76 mfspr r0,SPRN_HID0
77 li r11,5 /* clear DOZE and SLEEP */
78 rldimi r0,r11,52,8 /* set NAP and DPM */
79 mtspr SPRN_HID0,r0
80 mfspr r0,SPRN_HID0
81 mfspr r0,SPRN_HID0
82 mfspr r0,SPRN_HID0
83 mfspr r0,SPRN_HID0
84 mfspr r0,SPRN_HID0
85 mfspr r0,SPRN_HID0
86 sync
87 isync
88 blr
89
90/* Definitions for the table use to save CPU states */
91#define CS_HID0 0
92#define CS_HID1 8
93#define CS_HID4 16
94#define CS_HID5 24
95#define CS_SIZE 32
96
97 .data
98 .balign L1_CACHE_BYTES,0
99cpu_state_storage:
100 .space CS_SIZE
101 .balign L1_CACHE_BYTES,0
102 .text
103
104/* Called in normal context to backup CPU 0 state. This
105 * does not include cache settings. This function is also
106 * called for machine sleep. This does not include the MMU
107 * setup, BATs, etc... but rather the "special" registers
108 * like HID0, HID1, HID4, etc...
109 */
110_GLOBAL(__save_cpu_setup)
111 /* Some CR fields are volatile, we back it up all */
112 mfcr r7
113
114 /* Get storage ptr */
115 LOAD_REG_IMMEDIATE(r5,cpu_state_storage)
116
117 /* We only deal with 970 for now */
118 mfspr r0,SPRN_PVR
119 srwi r0,r0,16
120 cmpwi r0,0x39
121 beq 1f
122 cmpwi r0,0x3c
123 beq 1f
124 cmpwi r0,0x44
125 bne 2f
126
1271: /* skip if not running in HV mode */
128 mfmsr r0
129 rldicl. r0,r0,4,63
130 beq 2f
131
132 /* Save HID0,1,4 and 5 */
133 mfspr r3,SPRN_HID0
134 std r3,CS_HID0(r5)
135 mfspr r3,SPRN_HID1
136 std r3,CS_HID1(r5)
137 mfspr r3,SPRN_HID4
138 std r3,CS_HID4(r5)
139 mfspr r3,SPRN_HID5
140 std r3,CS_HID5(r5)
141
1422:
143 mtcr r7
144 blr
145
146/* Called with no MMU context (typically MSR:IR/DR off) to
147 * restore CPU state as backed up by the previous
148 * function. This does not include cache setting
149 */
150_GLOBAL(__restore_cpu_setup)
151 /* Get storage ptr (FIXME when using anton reloc as we
152 * are running with translation disabled here
153 */
154 LOAD_REG_IMMEDIATE(r5,cpu_state_storage)
155
156 /* We only deal with 970 for now */
157 mfspr r0,SPRN_PVR
158 srwi r0,r0,16
159 cmpwi r0,0x39
160 beq 1f
161 cmpwi r0,0x3c
162 beq 1f
163 cmpwi r0,0x44
164 bnelr
165
1661: /* skip if not running in HV mode */
167 mfmsr r0
168 rldicl. r0,r0,4,63
169 beqlr
170
171 /* Before accessing memory, we make sure rm_ci is clear */
172 li r0,0
173 mfspr r3,SPRN_HID4
174 rldimi r3,r0,40,23 /* clear bit 23 (rm_ci) */
175 sync
176 mtspr SPRN_HID4,r3
177 isync
178 sync
179
180 /* Clear interrupt prefix */
181 li r0,0
182 sync
183 mtspr SPRN_HIOR,0
184 isync
185
186 /* Restore HID0 */
187 ld r3,CS_HID0(r5)
188 sync
189 isync
190 mtspr SPRN_HID0,r3
191 mfspr r3,SPRN_HID0
192 mfspr r3,SPRN_HID0
193 mfspr r3,SPRN_HID0
194 mfspr r3,SPRN_HID0
195 mfspr r3,SPRN_HID0
196 mfspr r3,SPRN_HID0
197 sync
198 isync
199
200 /* Restore HID1 */
201 ld r3,CS_HID1(r5)
202 sync
203 isync
204 mtspr SPRN_HID1,r3
205 mtspr SPRN_HID1,r3
206 sync
207 isync
208
209 /* Restore HID4 */
210 ld r3,CS_HID4(r5)
211 sync
212 isync
213 mtspr SPRN_HID4,r3
214 sync
215 isync
216
217 /* Restore HID5 */
218 ld r3,CS_HID5(r5)
219 sync
220 isync
221 mtspr SPRN_HID5,r3
222 sync
223 isync
224 blr
225