aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/sibyte/sb1250/smp.c
blob: cad14003b84f2efc4a0fb746df799597af7e6f90 (plain) (blame)
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
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
/*
 * Copyright (C) 2001, 2002, 2003 Broadcom Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/kernel_stat.h>

#include <asm/mmu_context.h>
#include <asm/io.h>
#include <asm/fw/cfe/cfe_api.h>
#include <asm/sibyte/sb1250.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_int.h>

static void *mailbox_set_regs[] = {
	IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_SET_CPU),
	IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_SET_CPU)
};

static void *mailbox_clear_regs[] = {
	IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CLR_CPU),
	IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CLR_CPU)
};

static void *mailbox_regs[] = {
	IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CPU),
	IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CPU)
};

/*
 * SMP init and finish on secondary CPUs
 */
void __cpuinit sb1250_smp_init(void)
{
	unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
		STATUSF_IP1 | STATUSF_IP0;

	/* Set interrupt mask, but don't enable */
	change_c0_status(ST0_IM, imask);
}

/*
 * These are routines for dealing with the sb1250 smp capabilities
 * independent of board/firmware
 */

/*
 * Simple enough; everything is set up, so just poke the appropriate mailbox
 * register, and we should be set
 */
static void sb1250_send_ipi_single(int cpu, unsigned int action)
{
	__raw_writeq((((u64)action) << 48), mailbox_set_regs[cpu]);
}

static inline void sb1250_send_ipi_mask(cpumask_t mask, unsigned int action)
{
	unsigned int i;

	for_each_cpu_mask(i, mask)
		sb1250_send_ipi_single(i, action);
}

/*
 * Code to run on secondary just after probing the CPU
 */
static void __cpuinit sb1250_init_secondary(void)
{
	extern void sb1250_smp_init(void);

	sb1250_smp_init();
}

/*
 * Do any tidying up before marking online and running the idle
 * loop
 */
static void __cpuinit sb1250_smp_finish(void)
{
	extern void sb1250_clockevent_init(void);

	sb1250_clockevent_init();
	local_irq_enable();
}

/*
 * Final cleanup after all secondaries booted
 */
static void sb1250_cpus_done(void)
{
}

/*
 * Setup the PC, SP, and GP of a secondary processor and start it
 * running!
 */
static void __cpuinit sb1250_boot_secondary(int cpu, struct task_struct *idle)
{
	int retval;

	retval = cfe_cpu_start(cpu_logical_map(cpu), &smp_bootstrap,
			       __KSTK_TOS(idle),
			       (unsigned long)task_thread_info(idle), 0);
	if (retval != 0)
		printk("cfe_start_cpu(%i) returned %i\n" , cpu, retval);
}

/*
 * Use CFE to find out how many CPUs are available, setting up
 * cpu_possible_map and the logical/physical mappings.
 * XXXKW will the boot CPU ever not be physical 0?
 *
 * Common setup before any secondaries are started
 */
static void __init sb1250_smp_setup(void)
{
	int i, num;

	cpus_clear(cpu_possible_map);
	cpu_set(0, cpu_possible_map);
	__cpu_number_map[0] = 0;
	__cpu_logical_map[0] = 0;

	for (i = 1, num = 0; i < NR_CPUS; i++) {
		if (cfe_cpu_stop(i) == 0) {
			cpu_set(i, cpu_possible_map);
			__cpu_number_map[i] = ++num;
			__cpu_logical_map[num] = i;
		}
	}
	printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
}

static void __init sb1250_prepare_cpus(unsigned int max_cpus)
{
}

struct plat_smp_ops sb_smp_ops = {
	.send_ipi_single	= sb1250_send_ipi_single,
	.send_ipi_mask		= sb1250_send_ipi_mask,
	.init_secondary		= sb1250_init_secondary,
	.smp_finish		= sb1250_smp_finish,
	.cpus_done		= sb1250_cpus_done,
	.boot_secondary		= sb1250_boot_secondary,
	.smp_setup		= sb1250_smp_setup,
	.prepare_cpus		= sb1250_prepare_cpus,
};

void sb1250_mailbox_interrupt(void)
{
	int cpu = smp_processor_id();
	int irq = K_INT_MBOX_0;
	unsigned int action;

	kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
	/* Load the mailbox register to figure out what we're supposed to do */
	action = (____raw_readq(mailbox_regs[cpu]) >> 48) & 0xffff;

	/* Clear the mailbox to clear the interrupt */
	____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]);

	/*
	 * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the
	 * interrupt will do the reschedule for us
	 */

	if (action & SMP_CALL_FUNCTION)
		smp_call_function_interrupt();
}