1 /*
2 * Copyright (C) 2001, 2002, 2003 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #include <linux/init.h>
20 #include <linux/delay.h>
21 #include <linux/interrupt.h>
22 #include <linux/smp.h>
23 #include <linux/kernel_stat.h>
24
25 #include <asm/mmu_context.h>
26 #include <asm/io.h>
27 #include <asm/fw/cfe/cfe_api.h>
28 #include <asm/sibyte/sb1250.h>
29 #include <asm/sibyte/sb1250_regs.h>
30 #include <asm/sibyte/sb1250_int.h>
31
32 static void *mailbox_set_regs[] = {
33 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_SET_CPU),
34 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_SET_CPU)
35 };
36
37 static void *mailbox_clear_regs[] = {
38 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CLR_CPU),
39 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CLR_CPU)
40 };
41
42 static void *mailbox_regs[] = {
43 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CPU),
44 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CPU)
45 };
46
47 /*
48 * SMP init and finish on secondary CPUs
49 */
sb1250_smp_init(void)50 void __cpuinit sb1250_smp_init(void)
51 {
52 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
53 STATUSF_IP1 | STATUSF_IP0;
54
55 /* Set interrupt mask, but don't enable */
56 change_c0_status(ST0_IM, imask);
57 }
58
59 /*
60 * These are routines for dealing with the sb1250 smp capabilities
61 * independent of board/firmware
62 */
63
64 /*
65 * Simple enough; everything is set up, so just poke the appropriate mailbox
66 * register, and we should be set
67 */
sb1250_send_ipi_single(int cpu,unsigned int action)68 static void sb1250_send_ipi_single(int cpu, unsigned int action)
69 {
70 __raw_writeq((((u64)action) << 48), mailbox_set_regs[cpu]);
71 }
72
sb1250_send_ipi_mask(const struct cpumask * mask,unsigned int action)73 static inline void sb1250_send_ipi_mask(const struct cpumask *mask,
74 unsigned int action)
75 {
76 unsigned int i;
77
78 for_each_cpu(i, mask)
79 sb1250_send_ipi_single(i, action);
80 }
81
82 /*
83 * Code to run on secondary just after probing the CPU
84 */
sb1250_init_secondary(void)85 static void __cpuinit sb1250_init_secondary(void)
86 {
87 extern void sb1250_smp_init(void);
88
89 sb1250_smp_init();
90 }
91
92 /*
93 * Do any tidying up before marking online and running the idle
94 * loop
95 */
sb1250_smp_finish(void)96 static void __cpuinit sb1250_smp_finish(void)
97 {
98 extern void sb1250_clockevent_init(void);
99
100 sb1250_clockevent_init();
101 local_irq_enable();
102 }
103
104 /*
105 * Final cleanup after all secondaries booted
106 */
sb1250_cpus_done(void)107 static void sb1250_cpus_done(void)
108 {
109 }
110
111 /*
112 * Setup the PC, SP, and GP of a secondary processor and start it
113 * running!
114 */
sb1250_boot_secondary(int cpu,struct task_struct * idle)115 static void __cpuinit sb1250_boot_secondary(int cpu, struct task_struct *idle)
116 {
117 int retval;
118
119 retval = cfe_cpu_start(cpu_logical_map(cpu), &smp_bootstrap,
120 __KSTK_TOS(idle),
121 (unsigned long)task_thread_info(idle), 0);
122 if (retval != 0)
123 printk("cfe_start_cpu(%i) returned %i\n" , cpu, retval);
124 }
125
126 /*
127 * Use CFE to find out how many CPUs are available, setting up
128 * cpu_possible_map and the logical/physical mappings.
129 * XXXKW will the boot CPU ever not be physical 0?
130 *
131 * Common setup before any secondaries are started
132 */
sb1250_smp_setup(void)133 static void __init sb1250_smp_setup(void)
134 {
135 int i, num;
136
137 cpus_clear(cpu_possible_map);
138 cpu_set(0, cpu_possible_map);
139 __cpu_number_map[0] = 0;
140 __cpu_logical_map[0] = 0;
141
142 for (i = 1, num = 0; i < NR_CPUS; i++) {
143 if (cfe_cpu_stop(i) == 0) {
144 cpu_set(i, cpu_possible_map);
145 __cpu_number_map[i] = ++num;
146 __cpu_logical_map[num] = i;
147 }
148 }
149 printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
150 }
151
sb1250_prepare_cpus(unsigned int max_cpus)152 static void __init sb1250_prepare_cpus(unsigned int max_cpus)
153 {
154 }
155
156 struct plat_smp_ops sb_smp_ops = {
157 .send_ipi_single = sb1250_send_ipi_single,
158 .send_ipi_mask = sb1250_send_ipi_mask,
159 .init_secondary = sb1250_init_secondary,
160 .smp_finish = sb1250_smp_finish,
161 .cpus_done = sb1250_cpus_done,
162 .boot_secondary = sb1250_boot_secondary,
163 .smp_setup = sb1250_smp_setup,
164 .prepare_cpus = sb1250_prepare_cpus,
165 };
166
sb1250_mailbox_interrupt(void)167 void sb1250_mailbox_interrupt(void)
168 {
169 int cpu = smp_processor_id();
170 int irq = K_INT_MBOX_0;
171 unsigned int action;
172
173 kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
174 /* Load the mailbox register to figure out what we're supposed to do */
175 action = (____raw_readq(mailbox_regs[cpu]) >> 48) & 0xffff;
176
177 /* Clear the mailbox to clear the interrupt */
178 ____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]);
179
180 /*
181 * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the
182 * interrupt will do the reschedule for us
183 */
184
185 if (action & SMP_CALL_FUNCTION)
186 smp_call_function_interrupt();
187 }
188