xref: /openbmc/linux/arch/mips/sgi-ip27/ip27-smp.c (revision 842ed298)
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 	for (i = 0; i < MAX_NUMNODES; i++) {
74 		nasid_t nasid = gdap->g_nasidtable[i];
75 		if (nasid == INVALID_NASID)
76 			break;
77 		node_set_online(nasid);
78 		highest = node_scan_cpus(nasid, highest);
79 	}
80 
81 	printk("Discovered %d cpus on %d nodes\n", highest + 1, num_online_nodes());
82 }
83 
84 static __init void intr_clear_all(nasid_t nasid)
85 {
86 	int i;
87 
88 	REMOTE_HUB_S(nasid, PI_INT_MASK0_A, 0);
89 	REMOTE_HUB_S(nasid, PI_INT_MASK0_B, 0);
90 	REMOTE_HUB_S(nasid, PI_INT_MASK1_A, 0);
91 	REMOTE_HUB_S(nasid, PI_INT_MASK1_B, 0);
92 
93 	for (i = 0; i < 128; i++)
94 		REMOTE_HUB_CLR_INTR(nasid, i);
95 }
96 
97 static void ip27_send_ipi_single(int destid, unsigned int action)
98 {
99 	int irq;
100 
101 	switch (action) {
102 	case SMP_RESCHEDULE_YOURSELF:
103 		irq = CPU_RESCHED_A_IRQ;
104 		break;
105 	case SMP_CALL_FUNCTION:
106 		irq = CPU_CALL_A_IRQ;
107 		break;
108 	default:
109 		panic("sendintr");
110 	}
111 
112 	irq += cputoslice(destid);
113 
114 	/*
115 	 * Set the interrupt bit associated with the CPU we want to
116 	 * send the interrupt to.
117 	 */
118 	REMOTE_HUB_SEND_INTR(cpu_to_node(destid), irq);
119 }
120 
121 static void ip27_send_ipi_mask(const struct cpumask *mask, unsigned int action)
122 {
123 	unsigned int i;
124 
125 	for_each_cpu(i, mask)
126 		ip27_send_ipi_single(i, action);
127 }
128 
129 static void ip27_init_cpu(void)
130 {
131 	per_cpu_init();
132 }
133 
134 static void ip27_smp_finish(void)
135 {
136 	hub_rt_clock_event_init();
137 	local_irq_enable();
138 }
139 
140 /*
141  * Launch a slave into smp_bootstrap().	 It doesn't take an argument, and we
142  * set sp to the kernel stack of the newly created idle process, gp to the proc
143  * struct so that current_thread_info() will work.
144  */
145 static int ip27_boot_secondary(int cpu, struct task_struct *idle)
146 {
147 	unsigned long gp = (unsigned long)task_thread_info(idle);
148 	unsigned long sp = __KSTK_TOS(idle);
149 
150 	LAUNCH_SLAVE(cputonasid(cpu), cputoslice(cpu),
151 		(launch_proc_t)MAPPED_KERN_RW_TO_K0(smp_bootstrap),
152 		0, (void *) sp, (void *) gp);
153 	return 0;
154 }
155 
156 static void __init ip27_smp_setup(void)
157 {
158 	nasid_t nasid;
159 
160 	for_each_online_node(nasid) {
161 		if (nasid == 0)
162 			continue;
163 		intr_clear_all(nasid);
164 	}
165 
166 	replicate_kernel_text();
167 
168 	/*
169 	 * PROM sets up system, that boot cpu is always first CPU on nasid 0
170 	 */
171 	cputonasid(0) = 0;
172 	cputoslice(0) = LOCAL_HUB_L(PI_CPU_NUM);
173 }
174 
175 static void __init ip27_prepare_cpus(unsigned int max_cpus)
176 {
177 	/* We already did everything necessary earlier */
178 }
179 
180 const struct plat_smp_ops ip27_smp_ops = {
181 	.send_ipi_single	= ip27_send_ipi_single,
182 	.send_ipi_mask		= ip27_send_ipi_mask,
183 	.init_secondary		= ip27_init_cpu,
184 	.smp_finish		= ip27_smp_finish,
185 	.boot_secondary		= ip27_boot_secondary,
186 	.smp_setup		= ip27_smp_setup,
187 	.prepare_cpus		= ip27_prepare_cpus,
188 	.prepare_boot_cpu	= ip27_init_cpu,
189 };
190