xref: /openbmc/linux/arch/powerpc/platforms/ps3/smp.c (revision b6dcefde)
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 /**
36   * ps3_ipi_virqs - a per cpu array of virqs for ipi use
37   */
38 
39 #define MSG_COUNT 4
40 static DEFINE_PER_CPU(unsigned int [MSG_COUNT], ps3_ipi_virqs);
41 
42 static void do_message_pass(int target, int msg)
43 {
44 	int result;
45 	unsigned int virq;
46 
47 	if (msg >= MSG_COUNT) {
48 		DBG("%s:%d: bad msg: %d\n", __func__, __LINE__, msg);
49 		return;
50 	}
51 
52 	virq = per_cpu(ps3_ipi_virqs, target)[msg];
53 	result = ps3_send_event_locally(virq);
54 
55 	if (result)
56 		DBG("%s:%d: ps3_send_event_locally(%d, %d) failed"
57 			" (%d)\n", __func__, __LINE__, target, msg, result);
58 }
59 
60 static void ps3_smp_message_pass(int target, int msg)
61 {
62 	int cpu;
63 
64 	if (target < NR_CPUS)
65 		do_message_pass(target, msg);
66 	else if (target == MSG_ALL_BUT_SELF) {
67 		for_each_online_cpu(cpu)
68 			if (cpu != smp_processor_id())
69 				do_message_pass(cpu, msg);
70 	} else {
71 		for_each_online_cpu(cpu)
72 			do_message_pass(cpu, msg);
73 	}
74 }
75 
76 static int ps3_smp_probe(void)
77 {
78 	return 2;
79 }
80 
81 static void __init ps3_smp_setup_cpu(int cpu)
82 {
83 	int result;
84 	unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
85 	int i;
86 
87 	DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
88 
89 	/*
90 	 * Check assumptions on ps3_ipi_virqs[] indexing. If this
91 	 * check fails, then a different mapping of PPC_MSG_
92 	 * to index needs to be setup.
93 	 */
94 
95 	BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION    != 0);
96 	BUILD_BUG_ON(PPC_MSG_RESCHEDULE       != 1);
97 	BUILD_BUG_ON(PPC_MSG_CALL_FUNC_SINGLE != 2);
98 	BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK   != 3);
99 
100 	for (i = 0; i < MSG_COUNT; i++) {
101 		result = ps3_event_receive_port_setup(cpu, &virqs[i]);
102 
103 		if (result)
104 			continue;
105 
106 		DBG("%s:%d: (%d, %d) => virq %u\n",
107 			__func__, __LINE__, cpu, i, virqs[i]);
108 
109 		result = smp_request_message_ipi(virqs[i], i);
110 
111 		if (result)
112 			virqs[i] = NO_IRQ;
113 	}
114 
115 	ps3_register_ipi_debug_brk(cpu, virqs[PPC_MSG_DEBUGGER_BREAK]);
116 
117 	DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
118 }
119 
120 void ps3_smp_cleanup_cpu(int cpu)
121 {
122 	unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
123 	int i;
124 
125 	DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
126 
127 	for (i = 0; i < MSG_COUNT; i++) {
128 		/* Can't call free_irq from interrupt context. */
129 		ps3_event_receive_port_destroy(virqs[i]);
130 		virqs[i] = NO_IRQ;
131 	}
132 
133 	DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
134 }
135 
136 static struct smp_ops_t ps3_smp_ops = {
137 	.probe		= ps3_smp_probe,
138 	.message_pass	= ps3_smp_message_pass,
139 	.kick_cpu	= smp_generic_kick_cpu,
140 	.setup_cpu	= ps3_smp_setup_cpu,
141 };
142 
143 void smp_init_ps3(void)
144 {
145 	DBG(" -> %s\n", __func__);
146 	smp_ops = &ps3_smp_ops;
147 	DBG(" <- %s\n", __func__);
148 }
149