xref: /openbmc/linux/arch/powerpc/platforms/85xx/smp.c (revision b04b4f78)
1 /*
2  * Author: Andy Fleming <afleming@freescale.com>
3  * 	   Kumar Gala <galak@kernel.crashing.org>
4  *
5  * Copyright 2006-2008 Freescale Semiconductor Inc.
6  *
7  * This program is free software; you can redistribute  it and/or modify it
8  * under  the terms of  the GNU General  Public License as published by the
9  * Free Software Foundation;  either version 2 of the  License, or (at your
10  * option) any later version.
11  */
12 
13 #include <linux/stddef.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/delay.h>
17 #include <linux/of.h>
18 
19 #include <asm/machdep.h>
20 #include <asm/pgtable.h>
21 #include <asm/page.h>
22 #include <asm/mpic.h>
23 #include <asm/cacheflush.h>
24 #include <asm/dbell.h>
25 
26 #include <sysdev/fsl_soc.h>
27 
28 extern volatile unsigned long __secondary_hold_acknowledge;
29 extern void __early_start(void);
30 
31 #define BOOT_ENTRY_ADDR_UPPER	0
32 #define BOOT_ENTRY_ADDR_LOWER	1
33 #define BOOT_ENTRY_R3_UPPER	2
34 #define BOOT_ENTRY_R3_LOWER	3
35 #define BOOT_ENTRY_RESV		4
36 #define BOOT_ENTRY_PIR		5
37 #define BOOT_ENTRY_R6_UPPER	6
38 #define BOOT_ENTRY_R6_LOWER	7
39 #define NUM_BOOT_ENTRY		8
40 #define SIZE_BOOT_ENTRY		(NUM_BOOT_ENTRY * sizeof(u32))
41 
42 static void __init
43 smp_85xx_kick_cpu(int nr)
44 {
45 	unsigned long flags;
46 	const u64 *cpu_rel_addr;
47 	__iomem u32 *bptr_vaddr;
48 	struct device_node *np;
49 	int n = 0;
50 
51 	WARN_ON (nr < 0 || nr >= NR_CPUS);
52 
53 	pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
54 
55 	local_irq_save(flags);
56 
57 	np = of_get_cpu_node(nr, NULL);
58 	cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
59 
60 	if (cpu_rel_addr == NULL) {
61 		printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
62 		local_irq_restore(flags);
63 		return;
64 	}
65 
66 	/* Map the spin table */
67 	bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
68 
69 	out_be32(bptr_vaddr + BOOT_ENTRY_PIR, nr);
70 	out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
71 
72 	/* Wait a bit for the CPU to ack. */
73 	while ((__secondary_hold_acknowledge != nr) && (++n < 1000))
74 		mdelay(1);
75 
76 	iounmap(bptr_vaddr);
77 
78 	local_irq_restore(flags);
79 
80 	pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
81 }
82 
83 static void __init
84 smp_85xx_basic_setup(int cpu_nr)
85 {
86 	/* Clear any pending timer interrupts */
87 	mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);
88 
89 	/* Enable decrementer interrupt */
90 	mtspr(SPRN_TCR, TCR_DIE);
91 }
92 
93 static void __init
94 smp_85xx_setup_cpu(int cpu_nr)
95 {
96 	mpic_setup_this_cpu();
97 
98 	smp_85xx_basic_setup(cpu_nr);
99 }
100 
101 struct smp_ops_t smp_85xx_ops = {
102 	.kick_cpu = smp_85xx_kick_cpu,
103 };
104 
105 static int __init smp_dummy_probe(void)
106 {
107 	return NR_CPUS;
108 }
109 
110 void __init mpc85xx_smp_init(void)
111 {
112 	struct device_node *np;
113 
114 	smp_85xx_ops.message_pass = NULL;
115 
116 	np = of_find_node_by_type(NULL, "open-pic");
117 	if (np) {
118 		smp_85xx_ops.probe = smp_mpic_probe;
119 		smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
120 		smp_85xx_ops.message_pass = smp_mpic_message_pass;
121 	} else {
122 		smp_85xx_ops.probe = smp_dummy_probe;
123 		smp_85xx_ops.setup_cpu = smp_85xx_basic_setup;
124 	}
125 
126 	if (cpu_has_feature(CPU_FTR_DBELL))
127 		smp_85xx_ops.message_pass = smp_dbell_message_pass;
128 
129 	BUG_ON(!smp_85xx_ops.message_pass);
130 
131 	smp_ops = &smp_85xx_ops;
132 }
133