xref: /linux/arch/mips/sgi-ip27/ip27-smp.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 /*
2  * This file is subject to the terms and conditions of the GNU General
3  * Public License.  See the file "COPYING" in the main directory of this
4  * archive for more details.
5  *
6  * Copyright (C) 2000 - 2001 by Kanoj Sarcar (kanoj@sgi.com)
7  * Copyright (C) 2000 - 2001 by Silicon Graphics, Inc.
8  */
9 #include <linux/init.h>
10 #include <linux/sched.h>
11 #include <linux/sched/task_stack.h>
12 #include <linux/topology.h>
13 #include <linux/nodemask.h>
14 
15 #include <asm/page.h>
16 #include <asm/processor.h>
17 #include <asm/ptrace.h>
18 #include <asm/sn/agent.h>
19 #include <asm/sn/arch.h>
20 #include <asm/sn/gda.h>
21 #include <asm/sn/intr.h>
22 #include <asm/sn/klconfig.h>
23 #include <asm/sn/launch.h>
24 #include <asm/sn/mapped_kernel.h>
25 #include <asm/sn/types.h>
26 
27 #include "ip27-common.h"
28 
29 static int node_scan_cpus(nasid_t nasid, int highest)
30 {
31 	static int cpus_found;
32 	lboard_t *brd;
33 	klcpu_t *acpu;
34 	cpuid_t cpuid;
35 
36 	brd = find_lboard((lboard_t *)KL_CONFIG_INFO(nasid), KLTYPE_IP27);
37 
38 	do {
39 		acpu = (klcpu_t *)find_first_component(brd, KLSTRUCT_CPU);
40 		while (acpu) {
41 			cpuid = acpu->cpu_info.virtid;
42 			/* Only let it join in if it's marked enabled */
43 			if ((acpu->cpu_info.flags & KLINFO_ENABLE) &&
44 			    (cpus_found != NR_CPUS)) {
45 				if (cpuid > highest)
46 					highest = cpuid;
47 				set_cpu_possible(cpuid, true);
48 				cputonasid(cpus_found) = nasid;
49 				cputoslice(cpus_found) = acpu->cpu_info.physid;
50 				sn_cpu_info[cpus_found].p_speed =
51 							acpu->cpu_speed;
52 				cpus_found++;
53 			}
54 			acpu = (klcpu_t *)find_component(brd, (klinfo_t *)acpu,
55 								KLSTRUCT_CPU);
56 		}
57 		brd = KLCF_NEXT(brd);
58 		if (!brd)
59 			break;
60 
61 		brd = find_lboard(brd, KLTYPE_IP27);
62 	} while (brd);
63 
64 	return highest;
65 }
66 
67 void cpu_node_probe(void)
68 {
69 	int i, highest = 0;
70 	gda_t *gdap = GDA;
71 
72 	nodes_clear(node_online_map);
73 	nodes_clear(node_possible_map);
74 	for (i = 0; i < MAX_NUMNODES; i++) {
75 		nasid_t nasid = gdap->g_nasidtable[i];
76 		if (nasid == INVALID_NASID)
77 			break;
78 		node_set_online(nasid);
79 		node_set(nasid, node_possible_map);
80 		highest = node_scan_cpus(nasid, highest);
81 	}
82 
83 	printk("Discovered %d cpus on %d nodes\n", highest + 1, num_online_nodes());
84 }
85 
86 static __init void intr_clear_all(nasid_t nasid)
87 {
88 	int i;
89 
90 	REMOTE_HUB_S(nasid, PI_INT_MASK0_A, 0);
91 	REMOTE_HUB_S(nasid, PI_INT_MASK0_B, 0);
92 	REMOTE_HUB_S(nasid, PI_INT_MASK1_A, 0);
93 	REMOTE_HUB_S(nasid, PI_INT_MASK1_B, 0);
94 
95 	for (i = 0; i < 128; i++)
96 		REMOTE_HUB_CLR_INTR(nasid, i);
97 }
98 
99 static void ip27_send_ipi_single(int destid, unsigned int action)
100 {
101 	int irq;
102 
103 	switch (action) {
104 	case SMP_RESCHEDULE_YOURSELF:
105 		irq = CPU_RESCHED_A_IRQ;
106 		break;
107 	case SMP_CALL_FUNCTION:
108 		irq = CPU_CALL_A_IRQ;
109 		break;
110 	default:
111 		panic("sendintr");
112 	}
113 
114 	irq += cputoslice(destid);
115 
116 	/*
117 	 * Set the interrupt bit associated with the CPU we want to
118 	 * send the interrupt to.
119 	 */
120 	REMOTE_HUB_SEND_INTR(cpu_to_node(destid), irq);
121 }
122 
123 static void ip27_send_ipi_mask(const struct cpumask *mask, unsigned int action)
124 {
125 	unsigned int i;
126 
127 	for_each_cpu(i, mask)
128 		ip27_send_ipi_single(i, action);
129 }
130 
131 static void ip27_init_cpu(void)
132 {
133 	per_cpu_init();
134 }
135 
136 static void ip27_smp_finish(void)
137 {
138 	hub_rt_clock_event_init();
139 	local_irq_enable();
140 }
141 
142 /*
143  * Launch a slave into smp_bootstrap().	 It doesn't take an argument, and we
144  * set sp to the kernel stack of the newly created idle process, gp to the proc
145  * struct so that current_thread_info() will work.
146  */
147 static int ip27_boot_secondary(int cpu, struct task_struct *idle)
148 {
149 	unsigned long gp = (unsigned long)task_thread_info(idle);
150 	unsigned long sp = __KSTK_TOS(idle);
151 
152 	LAUNCH_SLAVE(cputonasid(cpu), cputoslice(cpu),
153 		(launch_proc_t)MAPPED_KERN_RW_TO_K0(smp_bootstrap),
154 		0, (void *) sp, (void *) gp);
155 	return 0;
156 }
157 
158 static void __init ip27_smp_setup(void)
159 {
160 	nasid_t nasid;
161 
162 	for_each_online_node(nasid) {
163 		if (nasid == 0)
164 			continue;
165 		intr_clear_all(nasid);
166 	}
167 
168 	replicate_kernel_text();
169 
170 	/*
171 	 * PROM sets up system, that boot cpu is always first CPU on nasid 0
172 	 */
173 	cputonasid(0) = 0;
174 	cputoslice(0) = LOCAL_HUB_L(PI_CPU_NUM);
175 }
176 
177 static void __init ip27_prepare_cpus(unsigned int max_cpus)
178 {
179 	/* We already did everything necessary earlier */
180 }
181 
182 const struct plat_smp_ops ip27_smp_ops = {
183 	.send_ipi_single	= ip27_send_ipi_single,
184 	.send_ipi_mask		= ip27_send_ipi_mask,
185 	.init_secondary		= ip27_init_cpu,
186 	.smp_finish		= ip27_smp_finish,
187 	.boot_secondary		= ip27_boot_secondary,
188 	.smp_setup		= ip27_smp_setup,
189 	.prepare_cpus		= ip27_prepare_cpus,
190 	.prepare_boot_cpu	= ip27_init_cpu,
191 };
192