1 /*
2  * PowerNV setup code.
3  *
4  * Copyright 2011 IBM Corp.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #undef DEBUG
13 
14 #include <linux/cpu.h>
15 #include <linux/errno.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
18 #include <linux/tty.h>
19 #include <linux/reboot.h>
20 #include <linux/init.h>
21 #include <linux/console.h>
22 #include <linux/delay.h>
23 #include <linux/irq.h>
24 #include <linux/seq_file.h>
25 #include <linux/of.h>
26 #include <linux/interrupt.h>
27 #include <linux/bug.h>
28 
29 #include <asm/machdep.h>
30 #include <asm/firmware.h>
31 #include <asm/xics.h>
32 #include <asm/rtas.h>
33 #include <asm/opal.h>
34 #include <asm/kexec.h>
35 
36 #include "powernv.h"
37 
38 static void __init pnv_setup_arch(void)
39 {
40 	/* Initialize SMP */
41 	pnv_smp_init();
42 
43 	/* Setup PCI */
44 	pnv_pci_init();
45 
46 	/* Setup RTC and NVRAM callbacks */
47 	if (firmware_has_feature(FW_FEATURE_OPAL))
48 		opal_nvram_init();
49 
50 	/* Enable NAP mode */
51 	powersave_nap = 1;
52 
53 	/* XXX PMCS */
54 }
55 
56 static void __init pnv_init_early(void)
57 {
58 	/*
59 	 * Initialize the LPC bus now so that legacy serial
60 	 * ports can be found on it
61 	 */
62 	opal_lpc_init();
63 
64 #ifdef CONFIG_HVC_OPAL
65 	if (firmware_has_feature(FW_FEATURE_OPAL))
66 		hvc_opal_init_early();
67 	else
68 #endif
69 		add_preferred_console("hvc", 0, NULL);
70 }
71 
72 static void __init pnv_init_IRQ(void)
73 {
74 	xics_init();
75 
76 	WARN_ON(!ppc_md.get_irq);
77 }
78 
79 static void pnv_show_cpuinfo(struct seq_file *m)
80 {
81 	struct device_node *root;
82 	const char *model = "";
83 
84 	root = of_find_node_by_path("/");
85 	if (root)
86 		model = of_get_property(root, "model", NULL);
87 	seq_printf(m, "machine\t\t: PowerNV %s\n", model);
88 	if (firmware_has_feature(FW_FEATURE_OPALv3))
89 		seq_printf(m, "firmware\t: OPAL v3\n");
90 	else if (firmware_has_feature(FW_FEATURE_OPALv2))
91 		seq_printf(m, "firmware\t: OPAL v2\n");
92 	else if (firmware_has_feature(FW_FEATURE_OPAL))
93 		seq_printf(m, "firmware\t: OPAL v1\n");
94 	else
95 		seq_printf(m, "firmware\t: BML\n");
96 	of_node_put(root);
97 }
98 
99 static void  __noreturn pnv_restart(char *cmd)
100 {
101 	long rc = OPAL_BUSY;
102 
103 	opal_notifier_disable();
104 
105 	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
106 		rc = opal_cec_reboot();
107 		if (rc == OPAL_BUSY_EVENT)
108 			opal_poll_events(NULL);
109 		else
110 			mdelay(10);
111 	}
112 	for (;;)
113 		opal_poll_events(NULL);
114 }
115 
116 static void __noreturn pnv_power_off(void)
117 {
118 	long rc = OPAL_BUSY;
119 
120 	opal_notifier_disable();
121 
122 	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
123 		rc = opal_cec_power_down(0);
124 		if (rc == OPAL_BUSY_EVENT)
125 			opal_poll_events(NULL);
126 		else
127 			mdelay(10);
128 	}
129 	for (;;)
130 		opal_poll_events(NULL);
131 }
132 
133 static void __noreturn pnv_halt(void)
134 {
135 	pnv_power_off();
136 }
137 
138 static void pnv_progress(char *s, unsigned short hex)
139 {
140 }
141 
142 static void pnv_shutdown(void)
143 {
144 	/* Let the PCI code clear up IODA tables */
145 	pnv_pci_shutdown();
146 
147 	/* And unregister all OPAL interrupts so they don't fire
148 	 * up while we kexec
149 	 */
150 	opal_shutdown();
151 }
152 
153 #ifdef CONFIG_KEXEC
154 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
155 {
156 	xics_kexec_teardown_cpu(secondary);
157 
158 	/* Return secondary CPUs to firmware on OPAL v3 */
159 	if (firmware_has_feature(FW_FEATURE_OPALv3) && secondary) {
160 		mb();
161 		get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
162 		mb();
163 
164 		/* Return the CPU to OPAL */
165 		opal_return_cpu();
166 	}
167 }
168 #endif /* CONFIG_KEXEC */
169 
170 static void __init pnv_setup_machdep_opal(void)
171 {
172 	ppc_md.get_boot_time = opal_get_boot_time;
173 	ppc_md.get_rtc_time = opal_get_rtc_time;
174 	ppc_md.set_rtc_time = opal_set_rtc_time;
175 	ppc_md.restart = pnv_restart;
176 	ppc_md.power_off = pnv_power_off;
177 	ppc_md.halt = pnv_halt;
178 	ppc_md.machine_check_exception = opal_machine_check;
179 }
180 
181 #ifdef CONFIG_PPC_POWERNV_RTAS
182 static void __init pnv_setup_machdep_rtas(void)
183 {
184 	if (rtas_token("get-time-of-day") != RTAS_UNKNOWN_SERVICE) {
185 		ppc_md.get_boot_time = rtas_get_boot_time;
186 		ppc_md.get_rtc_time = rtas_get_rtc_time;
187 		ppc_md.set_rtc_time = rtas_set_rtc_time;
188 	}
189 	ppc_md.restart = rtas_restart;
190 	ppc_md.power_off = rtas_power_off;
191 	ppc_md.halt = rtas_halt;
192 }
193 #endif /* CONFIG_PPC_POWERNV_RTAS */
194 
195 static int __init pnv_probe(void)
196 {
197 	unsigned long root = of_get_flat_dt_root();
198 
199 	if (!of_flat_dt_is_compatible(root, "ibm,powernv"))
200 		return 0;
201 
202 	hpte_init_native();
203 
204 	if (firmware_has_feature(FW_FEATURE_OPAL))
205 		pnv_setup_machdep_opal();
206 #ifdef CONFIG_PPC_POWERNV_RTAS
207 	else if (rtas.base)
208 		pnv_setup_machdep_rtas();
209 #endif /* CONFIG_PPC_POWERNV_RTAS */
210 
211 	pr_debug("PowerNV detected !\n");
212 
213 	return 1;
214 }
215 
216 define_machine(powernv) {
217 	.name			= "PowerNV",
218 	.probe			= pnv_probe,
219 	.init_early		= pnv_init_early,
220 	.setup_arch		= pnv_setup_arch,
221 	.init_IRQ		= pnv_init_IRQ,
222 	.show_cpuinfo		= pnv_show_cpuinfo,
223 	.progress		= pnv_progress,
224 	.machine_shutdown	= pnv_shutdown,
225 	.power_save             = power7_idle,
226 	.calibrate_decr		= generic_calibrate_decr,
227 #ifdef CONFIG_KEXEC
228 	.kexec_cpu_down		= pnv_kexec_cpu_down,
229 #endif
230 };
231