xref: /openbmc/linux/arch/powerpc/platforms/ps3/smp.c (revision 93dc544c)
1 /*
2  *  PS3 SMP routines.
3  *
4  *  Copyright (C) 2006 Sony Computer Entertainment Inc.
5  *  Copyright 2006 Sony Corp.
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; version 2 of the License.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/smp.h>
23 
24 #include <asm/machdep.h>
25 #include <asm/udbg.h>
26 
27 #include "platform.h"
28 
29 #if defined(DEBUG)
30 #define DBG udbg_printf
31 #else
32 #define DBG pr_debug
33 #endif
34 
35 static irqreturn_t ipi_function_handler(int irq, void *msg)
36 {
37 	smp_message_recv((int)(long)msg);
38 	return IRQ_HANDLED;
39 }
40 
41 /**
42   * ps3_ipi_virqs - a per cpu array of virqs for ipi use
43   */
44 
45 #define MSG_COUNT 4
46 static DEFINE_PER_CPU(unsigned int, ps3_ipi_virqs[MSG_COUNT]);
47 
48 static const char *names[MSG_COUNT] = {
49 	"ipi call",
50 	"ipi reschedule",
51 	"ipi migrate",
52 	"ipi debug brk"
53 };
54 
55 static void do_message_pass(int target, int msg)
56 {
57 	int result;
58 	unsigned int virq;
59 
60 	if (msg >= MSG_COUNT) {
61 		DBG("%s:%d: bad msg: %d\n", __func__, __LINE__, msg);
62 		return;
63 	}
64 
65 	virq = per_cpu(ps3_ipi_virqs, target)[msg];
66 	result = ps3_send_event_locally(virq);
67 
68 	if (result)
69 		DBG("%s:%d: ps3_send_event_locally(%d, %d) failed"
70 			" (%d)\n", __func__, __LINE__, target, msg, result);
71 }
72 
73 static void ps3_smp_message_pass(int target, int msg)
74 {
75 	int cpu;
76 
77 	if (target < NR_CPUS)
78 		do_message_pass(target, msg);
79 	else if (target == MSG_ALL_BUT_SELF) {
80 		for_each_online_cpu(cpu)
81 			if (cpu != smp_processor_id())
82 				do_message_pass(cpu, msg);
83 	} else {
84 		for_each_online_cpu(cpu)
85 			do_message_pass(cpu, msg);
86 	}
87 }
88 
89 static int ps3_smp_probe(void)
90 {
91 	return 2;
92 }
93 
94 static void __init ps3_smp_setup_cpu(int cpu)
95 {
96 	int result;
97 	unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
98 	int i;
99 
100 	DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
101 
102 	/*
103 	 * Check assumptions on ps3_ipi_virqs[] indexing. If this
104 	 * check fails, then a different mapping of PPC_MSG_
105 	 * to index needs to be setup.
106 	 */
107 
108 	BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION    != 0);
109 	BUILD_BUG_ON(PPC_MSG_RESCHEDULE       != 1);
110 	BUILD_BUG_ON(PPC_MSG_CALL_FUNC_SINGLE != 2);
111 	BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK   != 3);
112 
113 	for (i = 0; i < MSG_COUNT; i++) {
114 		result = ps3_event_receive_port_setup(cpu, &virqs[i]);
115 
116 		if (result)
117 			continue;
118 
119 		DBG("%s:%d: (%d, %d) => virq %u\n",
120 			__func__, __LINE__, cpu, i, virqs[i]);
121 
122 		result = request_irq(virqs[i], ipi_function_handler,
123 			IRQF_DISABLED, names[i], (void*)(long)i);
124 
125 		if (result)
126 			virqs[i] = NO_IRQ;
127 	}
128 
129 	ps3_register_ipi_debug_brk(cpu, virqs[PPC_MSG_DEBUGGER_BREAK]);
130 
131 	DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
132 }
133 
134 void ps3_smp_cleanup_cpu(int cpu)
135 {
136 	unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
137 	int i;
138 
139 	DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
140 
141 	for (i = 0; i < MSG_COUNT; i++) {
142 		/* Can't call free_irq from interrupt context. */
143 		ps3_event_receive_port_destroy(virqs[i]);
144 		virqs[i] = NO_IRQ;
145 	}
146 
147 	DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
148 }
149 
150 static struct smp_ops_t ps3_smp_ops = {
151 	.probe		= ps3_smp_probe,
152 	.message_pass	= ps3_smp_message_pass,
153 	.kick_cpu	= smp_generic_kick_cpu,
154 	.setup_cpu	= ps3_smp_setup_cpu,
155 };
156 
157 void smp_init_ps3(void)
158 {
159 	DBG(" -> %s\n", __func__);
160 	smp_ops = &ps3_smp_ops;
161 	DBG(" <- %s\n", __func__);
162 }
163