1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* SMP support for BPA machines.
*
* Dave Engebretsen, Peter Bergner, and
* Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
*
* Plus various changes from other IBM teams...
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/cpu.h>
#include <linux/pgtable.h>
#include <asm/ptrace.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/paca.h>
#include <asm/machdep.h>
#include <asm/cputable.h>
#include <asm/firmware.h>
#include <asm/rtas.h>
#include <asm/cputhreads.h>
#include <asm/code-patching.h>
#include "interrupt.h"
#include <asm/udbg.h>
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
/*
* The Primary thread of each non-boot processor was started from the OF client
* interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
*/
static cpumask_t of_spin_map;
/**
* smp_startup_cpu() - start the given cpu
*
* At boot time, there is nothing to do for primary threads which were
* started from Open Firmware. For anything else, call RTAS with the
* appropriate start location.
*
* Returns:
* 0 - failure
* 1 - success
*/
static inline int smp_startup_cpu(unsigned int lcpu)
{
int status;
unsigned long start_here =
__pa(ppc_function_entry(generic_secondary_smp_init));
unsigned int pcpu;
int start_cpu;
if (cpumask_test_cpu(lcpu, &of_spin_map))
/* Already started by OF and sitting in spin loop */
return 1;
pcpu = get_hard_smp_processor_id(lcpu);
/*
* If the RTAS start-cpu token does not exist then presume the
* cpu is already spinning.
*/
start_cpu = rtas_token("start-cpu");
if (start_cpu == RTAS_UNKNOWN_SERVICE)
return 1;
status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, lcpu);
if (status != 0) {
printk(KERN_ERR "start-cpu failed: %i\n", status);
return 0;
}
return 1;
}
static void smp_cell_setup_cpu(int cpu)
{
if (cpu != boot_cpuid)
iic_setup_cpu();
/*
* change default DABRX to allow user watchpoints
*/
mtspr(SPRN_DABRX, DABRX_KERNEL | DABRX_USER);
}
static int smp_cell_kick_cpu(int nr)
{
if (nr < 0 || nr >= nr_cpu_ids)
return -EINVAL;
if (!smp_startup_cpu(nr))
return -ENOENT;
/*
* The processor is currently spinning, waiting for the
* cpu_start field to become non-zero After we set cpu_start,
* the processor will continue on to secondary_start
*/
paca_ptrs[nr]->cpu_start = 1;
return 0;
}
static struct smp_ops_t bpa_iic_smp_ops = {
.message_pass = iic_message_pass,
.probe = iic_request_IPIs,
.kick_cpu = smp_cell_kick_cpu,
.setup_cpu = smp_cell_setup_cpu,
.cpu_bootable = smp_generic_cpu_bootable,
};
/* This is called very early */
void __init smp_init_cell(void)
{
int i;
DBG(" -> smp_init_cell()\n");
smp_ops = &bpa_iic_smp_ops;
/* Mark threads which are still spinning in hold loops. */
if (cpu_has_feature(CPU_FTR_SMT)) {
for_each_present_cpu(i) {
if (cpu_thread_in_core(i) == 0)
cpumask_set_cpu(i, &of_spin_map);
}
} else
cpumask_copy(&of_spin_map, cpu_present_mask);
cpumask_clear_cpu(boot_cpuid, &of_spin_map);
/* Non-lpar has additional take/give timebase */
if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) {
smp_ops->give_timebase = rtas_give_timebase;
smp_ops->take_timebase = rtas_take_timebase;
}
DBG(" <- smp_init_cell()\n");
}
|
