Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
69a80d3f | 2 | * SMP support for pSeries machines. |
1da177e4 LT |
3 | * |
4 | * Dave Engebretsen, Peter Bergner, and | |
5 | * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com | |
6 | * | |
7 | * Plus various changes from other IBM teams... | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU General Public License | |
11 | * as published by the Free Software Foundation; either version | |
12 | * 2 of the License, or (at your option) any later version. | |
13 | */ | |
14 | ||
1da177e4 | 15 | |
1da177e4 LT |
16 | #include <linux/kernel.h> |
17 | #include <linux/module.h> | |
18 | #include <linux/sched.h> | |
19 | #include <linux/smp.h> | |
20 | #include <linux/interrupt.h> | |
21 | #include <linux/delay.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/spinlock.h> | |
24 | #include <linux/cache.h> | |
25 | #include <linux/err.h> | |
26 | #include <linux/sysdev.h> | |
27 | #include <linux/cpu.h> | |
28 | ||
29 | #include <asm/ptrace.h> | |
30 | #include <asm/atomic.h> | |
31 | #include <asm/irq.h> | |
32 | #include <asm/page.h> | |
33 | #include <asm/pgtable.h> | |
34 | #include <asm/io.h> | |
35 | #include <asm/prom.h> | |
36 | #include <asm/smp.h> | |
37 | #include <asm/paca.h> | |
1da177e4 | 38 | #include <asm/machdep.h> |
1da177e4 | 39 | #include <asm/cputable.h> |
1ababe11 | 40 | #include <asm/firmware.h> |
1da177e4 LT |
41 | #include <asm/system.h> |
42 | #include <asm/rtas.h> | |
1da177e4 | 43 | #include <asm/pSeries_reconfig.h> |
bbeb3f4c | 44 | #include <asm/mpic.h> |
271c3f35 | 45 | #include <asm/vdso_datapage.h> |
8d089085 | 46 | #include <asm/cputhreads.h> |
0b05ac6e BH |
47 | #include <asm/mpic.h> |
48 | #include <asm/xics.h> | |
1da177e4 | 49 | |
a1218720 | 50 | #include "plpar_wrappers.h" |
8feaeca2 | 51 | #include "pseries.h" |
3aa565f5 | 52 | #include "offline_states.h" |
a1218720 | 53 | |
1da177e4 LT |
54 | |
55 | /* | |
6a75a6b8 MM |
56 | * The Primary thread of each non-boot processor was started from the OF client |
57 | * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop. | |
1da177e4 | 58 | */ |
af831e1e | 59 | static cpumask_var_t of_spin_mask; |
1da177e4 | 60 | |
f8b67691 MN |
61 | /* Query where a cpu is now. Return codes #defined in plpar_wrappers.h */ |
62 | int smp_query_cpu_stopped(unsigned int pcpu) | |
63 | { | |
64 | int cpu_status, status; | |
65 | int qcss_tok = rtas_token("query-cpu-stopped-state"); | |
66 | ||
67 | if (qcss_tok == RTAS_UNKNOWN_SERVICE) { | |
2d86938a MM |
68 | printk_once(KERN_INFO |
69 | "Firmware doesn't support query-cpu-stopped-state\n"); | |
f8b67691 MN |
70 | return QCSS_HARDWARE_ERROR; |
71 | } | |
72 | ||
73 | status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu); | |
74 | if (status != 0) { | |
75 | printk(KERN_ERR | |
76 | "RTAS query-cpu-stopped-state failed: %i\n", status); | |
77 | return status; | |
78 | } | |
79 | ||
80 | return cpu_status; | |
81 | } | |
82 | ||
1da177e4 LT |
83 | /** |
84 | * smp_startup_cpu() - start the given cpu | |
85 | * | |
86 | * At boot time, there is nothing to do for primary threads which were | |
87 | * started from Open Firmware. For anything else, call RTAS with the | |
88 | * appropriate start location. | |
89 | * | |
90 | * Returns: | |
91 | * 0 - failure | |
92 | * 1 - success | |
93 | */ | |
94 | static inline int __devinit smp_startup_cpu(unsigned int lcpu) | |
95 | { | |
96 | int status; | |
97 | unsigned long start_here = __pa((u32)*((unsigned long *) | |
f39b7a55 | 98 | generic_secondary_smp_init)); |
1da177e4 | 99 | unsigned int pcpu; |
1ed2fd2d | 100 | int start_cpu; |
1da177e4 | 101 | |
af831e1e | 102 | if (cpumask_test_cpu(lcpu, of_spin_mask)) |
1da177e4 LT |
103 | /* Already started by OF and sitting in spin loop */ |
104 | return 1; | |
105 | ||
106 | pcpu = get_hard_smp_processor_id(lcpu); | |
107 | ||
aef40e87 MN |
108 | /* Check to see if the CPU out of FW already for kexec */ |
109 | if (smp_query_cpu_stopped(pcpu) == QCSS_NOT_STOPPED){ | |
af831e1e | 110 | cpumask_set_cpu(lcpu, of_spin_mask); |
aef40e87 MN |
111 | return 1; |
112 | } | |
113 | ||
1da177e4 | 114 | /* Fixup atomic count: it exited inside IRQ handler. */ |
b5e2fc1c | 115 | task_thread_info(paca[lcpu].__current)->preempt_count = 0; |
c60e65d7 | 116 | #ifdef CONFIG_HOTPLUG_CPU |
3aa565f5 GS |
117 | if (get_cpu_current_state(lcpu) == CPU_STATE_INACTIVE) |
118 | goto out; | |
c60e65d7 | 119 | #endif |
1ed2fd2d AB |
120 | /* |
121 | * If the RTAS start-cpu token does not exist then presume the | |
122 | * cpu is already spinning. | |
123 | */ | |
124 | start_cpu = rtas_token("start-cpu"); | |
125 | if (start_cpu == RTAS_UNKNOWN_SERVICE) | |
126 | return 1; | |
127 | ||
496b7a51 | 128 | status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, pcpu); |
1da177e4 LT |
129 | if (status != 0) { |
130 | printk(KERN_ERR "start-cpu failed: %i\n", status); | |
131 | return 0; | |
132 | } | |
1ed2fd2d | 133 | |
c60e65d7 | 134 | #ifdef CONFIG_HOTPLUG_CPU |
3aa565f5 | 135 | out: |
c60e65d7 | 136 | #endif |
1da177e4 LT |
137 | return 1; |
138 | } | |
139 | ||
1da177e4 LT |
140 | static void __devinit smp_xics_setup_cpu(int cpu) |
141 | { | |
142 | if (cpu != boot_cpuid) | |
143 | xics_setup_cpu(); | |
144 | ||
1ababe11 | 145 | if (firmware_has_feature(FW_FEATURE_SPLPAR)) |
1da177e4 LT |
146 | vpa_init(cpu); |
147 | ||
af831e1e | 148 | cpumask_clear_cpu(cpu, of_spin_mask); |
c60e65d7 | 149 | #ifdef CONFIG_HOTPLUG_CPU |
3aa565f5 GS |
150 | set_cpu_current_state(cpu, CPU_STATE_ONLINE); |
151 | set_default_offline_state(cpu); | |
c60e65d7 | 152 | #endif |
1da177e4 LT |
153 | } |
154 | ||
1da177e4 LT |
155 | static void __devinit smp_pSeries_kick_cpu(int nr) |
156 | { | |
157 | BUG_ON(nr < 0 || nr >= NR_CPUS); | |
158 | ||
159 | if (!smp_startup_cpu(nr)) | |
160 | return; | |
161 | ||
162 | /* | |
163 | * The processor is currently spinning, waiting for the | |
164 | * cpu_start field to become non-zero After we set cpu_start, | |
165 | * the processor will continue on to secondary_start | |
166 | */ | |
167 | paca[nr].cpu_start = 1; | |
c60e65d7 | 168 | #ifdef CONFIG_HOTPLUG_CPU |
3aa565f5 GS |
169 | set_preferred_offline_state(nr, CPU_STATE_ONLINE); |
170 | ||
171 | if (get_cpu_current_state(nr) == CPU_STATE_INACTIVE) { | |
c60e65d7 ME |
172 | long rc; |
173 | unsigned long hcpuid; | |
174 | ||
3aa565f5 GS |
175 | hcpuid = get_hard_smp_processor_id(nr); |
176 | rc = plpar_hcall_norets(H_PROD, hcpuid); | |
177 | if (rc != H_SUCCESS) | |
5a2ad98e JP |
178 | printk(KERN_ERR "Error: Prod to wake up processor %d " |
179 | "Ret= %ld\n", nr, rc); | |
3aa565f5 | 180 | } |
c60e65d7 | 181 | #endif |
1da177e4 LT |
182 | } |
183 | ||
184 | static int smp_pSeries_cpu_bootable(unsigned int nr) | |
185 | { | |
186 | /* Special case - we inhibit secondary thread startup | |
6a75a6b8 | 187 | * during boot if the user requests it. |
1da177e4 | 188 | */ |
954e6da5 NF |
189 | if (system_state < SYSTEM_RUNNING && cpu_has_feature(CPU_FTR_SMT)) { |
190 | if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0) | |
191 | return 0; | |
192 | if (smt_enabled_at_boot | |
193 | && cpu_thread_in_core(nr) >= smt_enabled_at_boot) | |
194 | return 0; | |
195 | } | |
1da177e4 LT |
196 | |
197 | return 1; | |
198 | } | |
0b05ac6e | 199 | |
1da177e4 LT |
200 | static struct smp_ops_t pSeries_mpic_smp_ops = { |
201 | .message_pass = smp_mpic_message_pass, | |
202 | .probe = smp_mpic_probe, | |
203 | .kick_cpu = smp_pSeries_kick_cpu, | |
204 | .setup_cpu = smp_mpic_setup_cpu, | |
205 | }; | |
0b05ac6e | 206 | |
1da177e4 | 207 | static struct smp_ops_t pSeries_xics_smp_ops = { |
0b05ac6e BH |
208 | .message_pass = NULL, /* Filled at runtime by xics_smp_probe() */ |
209 | .probe = xics_smp_probe, | |
1da177e4 LT |
210 | .kick_cpu = smp_pSeries_kick_cpu, |
211 | .setup_cpu = smp_xics_setup_cpu, | |
212 | .cpu_bootable = smp_pSeries_cpu_bootable, | |
213 | }; | |
214 | ||
215 | /* This is called very early */ | |
0ebfff14 | 216 | static void __init smp_init_pseries(void) |
1da177e4 LT |
217 | { |
218 | int i; | |
219 | ||
f7ebf352 | 220 | pr_debug(" -> smp_init_pSeries()\n"); |
1da177e4 | 221 | |
af831e1e AB |
222 | alloc_bootmem_cpumask_var(&of_spin_mask); |
223 | ||
1da177e4 | 224 | /* Mark threads which are still spinning in hold loops. */ |
0231c290 AB |
225 | if (cpu_has_feature(CPU_FTR_SMT)) { |
226 | for_each_present_cpu(i) { | |
6a75a6b8 | 227 | if (cpu_thread_in_core(i) == 0) |
af831e1e | 228 | cpumask_set_cpu(i, of_spin_mask); |
1da177e4 | 229 | } |
0231c290 | 230 | } else { |
af831e1e | 231 | cpumask_copy(of_spin_mask, cpu_present_mask); |
0231c290 | 232 | } |
1da177e4 | 233 | |
af831e1e | 234 | cpumask_clear_cpu(boot_cpuid, of_spin_mask); |
1da177e4 LT |
235 | |
236 | /* Non-lpar has additional take/give timebase */ | |
237 | if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { | |
c4007a2f BH |
238 | smp_ops->give_timebase = rtas_give_timebase; |
239 | smp_ops->take_timebase = rtas_take_timebase; | |
1da177e4 LT |
240 | } |
241 | ||
f7ebf352 | 242 | pr_debug(" <- smp_init_pSeries()\n"); |
1da177e4 LT |
243 | } |
244 | ||
0ebfff14 BH |
245 | void __init smp_init_pseries_mpic(void) |
246 | { | |
247 | smp_ops = &pSeries_mpic_smp_ops; | |
248 | ||
249 | smp_init_pseries(); | |
250 | } | |
0ebfff14 BH |
251 | |
252 | void __init smp_init_pseries_xics(void) | |
253 | { | |
254 | smp_ops = &pSeries_xics_smp_ops; | |
255 | ||
256 | smp_init_pseries(); | |
257 | } |