1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * PPC476 board specific routines
4 *
5 * Copyright 2010 Torez Smith, IBM Corporation.
6 *
7 * Based on earlier code:
8 * Matt Porter <mporter@kernel.crashing.org>
9 * Copyright 2002-2005 MontaVista Software Inc.
10 *
11 * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
12 * Copyright (c) 2003-2005 Zultys Technologies
13 *
14 * Rewritten and ported to the merged powerpc tree:
15 * Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
16 */
17
18 #include <linux/init.h>
19 #include <linux/of_platform.h>
20 #include <linux/rtc.h>
21
22 #include <asm/machdep.h>
23 #include <asm/prom.h>
24 #include <asm/udbg.h>
25 #include <asm/time.h>
26 #include <asm/uic.h>
27 #include <asm/ppc4xx.h>
28 #include <asm/mpic.h>
29 #include <asm/mmu.h>
30
31 static const struct of_device_id iss4xx_of_bus[] __initconst = {
32 { .compatible = "ibm,plb4", },
33 { .compatible = "ibm,plb6", },
34 { .compatible = "ibm,opb", },
35 { .compatible = "ibm,ebc", },
36 {},
37 };
38
iss4xx_device_probe(void)39 static int __init iss4xx_device_probe(void)
40 {
41 of_platform_bus_probe(NULL, iss4xx_of_bus, NULL);
42 of_instantiate_rtc();
43
44 return 0;
45 }
46 machine_device_initcall(iss4xx, iss4xx_device_probe);
47
48 /* We can have either UICs or MPICs */
iss4xx_init_irq(void)49 static void __init iss4xx_init_irq(void)
50 {
51 struct device_node *np;
52
53 /* Find top level interrupt controller */
54 for_each_node_with_property(np, "interrupt-controller") {
55 if (of_get_property(np, "interrupts", NULL) == NULL)
56 break;
57 }
58 if (np == NULL)
59 panic("Can't find top level interrupt controller");
60
61 /* Check type and do appropriate initialization */
62 if (of_device_is_compatible(np, "ibm,uic")) {
63 uic_init_tree();
64 ppc_md.get_irq = uic_get_irq;
65 #ifdef CONFIG_MPIC
66 } else if (of_device_is_compatible(np, "chrp,open-pic")) {
67 /* The MPIC driver will get everything it needs from the
68 * device-tree, just pass 0 to all arguments
69 */
70 struct mpic *mpic = mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC ");
71 BUG_ON(mpic == NULL);
72 mpic_init(mpic);
73 ppc_md.get_irq = mpic_get_irq;
74 #endif
75 } else
76 panic("Unrecognized top level interrupt controller");
77 }
78
79 #ifdef CONFIG_SMP
smp_iss4xx_setup_cpu(int cpu)80 static void smp_iss4xx_setup_cpu(int cpu)
81 {
82 mpic_setup_this_cpu();
83 }
84
smp_iss4xx_kick_cpu(int cpu)85 static int smp_iss4xx_kick_cpu(int cpu)
86 {
87 struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
88 const u64 *spin_table_addr_prop;
89 u32 *spin_table;
90 extern void start_secondary_47x(void);
91
92 BUG_ON(cpunode == NULL);
93
94 /* Assume spin table. We could test for the enable-method in
95 * the device-tree but currently there's little point as it's
96 * our only supported method
97 */
98 spin_table_addr_prop = of_get_property(cpunode, "cpu-release-addr",
99 NULL);
100 if (spin_table_addr_prop == NULL) {
101 pr_err("CPU%d: Can't start, missing cpu-release-addr !\n", cpu);
102 return -ENOENT;
103 }
104
105 /* Assume it's mapped as part of the linear mapping. This is a bit
106 * fishy but will work fine for now
107 */
108 spin_table = (u32 *)__va(*spin_table_addr_prop);
109 pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
110
111 spin_table[3] = cpu;
112 smp_wmb();
113 spin_table[1] = __pa(start_secondary_47x);
114 mb();
115
116 return 0;
117 }
118
119 static struct smp_ops_t iss_smp_ops = {
120 .probe = smp_mpic_probe,
121 .message_pass = smp_mpic_message_pass,
122 .setup_cpu = smp_iss4xx_setup_cpu,
123 .kick_cpu = smp_iss4xx_kick_cpu,
124 .give_timebase = smp_generic_give_timebase,
125 .take_timebase = smp_generic_take_timebase,
126 };
127
iss4xx_smp_init(void)128 static void __init iss4xx_smp_init(void)
129 {
130 if (mmu_has_feature(MMU_FTR_TYPE_47x))
131 smp_ops = &iss_smp_ops;
132 }
133
134 #else /* CONFIG_SMP */
iss4xx_smp_init(void)135 static void __init iss4xx_smp_init(void) { }
136 #endif /* CONFIG_SMP */
137
iss4xx_setup_arch(void)138 static void __init iss4xx_setup_arch(void)
139 {
140 iss4xx_smp_init();
141 }
142
143 /*
144 * Called very early, MMU is off, device-tree isn't unflattened
145 */
iss4xx_probe(void)146 static int __init iss4xx_probe(void)
147 {
148 if (!of_machine_is_compatible("ibm,iss-4xx"))
149 return 0;
150
151 return 1;
152 }
153
define_machine(iss4xx)154 define_machine(iss4xx) {
155 .name = "ISS-4xx",
156 .probe = iss4xx_probe,
157 .progress = udbg_progress,
158 .init_IRQ = iss4xx_init_irq,
159 .setup_arch = iss4xx_setup_arch,
160 .restart = ppc4xx_reset_system,
161 .calibrate_decr = generic_calibrate_decr,
162 };
163
