Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cascardo/linux.git] / arch / powerpc / platforms / powernv / setup.c
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/of_fdt.h>
27 #include <linux/interrupt.h>
28 #include <linux/bug.h>
29 #include <linux/pci.h>
30 #include <linux/cpufreq.h>
31
32 #include <asm/machdep.h>
33 #include <asm/firmware.h>
34 #include <asm/xics.h>
35 #include <asm/rtas.h>
36 #include <asm/opal.h>
37 #include <asm/kexec.h>
38 #include <asm/smp.h>
39
40 #include "powernv.h"
41
42 static void __init pnv_setup_arch(void)
43 {
44         set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
45
46         /* Initialize SMP */
47         pnv_smp_init();
48
49         /* Setup PCI */
50         pnv_pci_init();
51
52         /* Setup RTC and NVRAM callbacks */
53         if (firmware_has_feature(FW_FEATURE_OPAL))
54                 opal_nvram_init();
55
56         /* Enable NAP mode */
57         powersave_nap = 1;
58
59         /* XXX PMCS */
60 }
61
62 static void __init pnv_init_early(void)
63 {
64         /*
65          * Initialize the LPC bus now so that legacy serial
66          * ports can be found on it
67          */
68         opal_lpc_init();
69
70 #ifdef CONFIG_HVC_OPAL
71         if (firmware_has_feature(FW_FEATURE_OPAL))
72                 hvc_opal_init_early();
73         else
74 #endif
75                 add_preferred_console("hvc", 0, NULL);
76 }
77
78 static void __init pnv_init_IRQ(void)
79 {
80         xics_init();
81
82         WARN_ON(!ppc_md.get_irq);
83 }
84
85 static void pnv_show_cpuinfo(struct seq_file *m)
86 {
87         struct device_node *root;
88         const char *model = "";
89
90         root = of_find_node_by_path("/");
91         if (root)
92                 model = of_get_property(root, "model", NULL);
93         seq_printf(m, "machine\t\t: PowerNV %s\n", model);
94         if (firmware_has_feature(FW_FEATURE_OPALv3))
95                 seq_printf(m, "firmware\t: OPAL v3\n");
96         else if (firmware_has_feature(FW_FEATURE_OPALv2))
97                 seq_printf(m, "firmware\t: OPAL v2\n");
98         else if (firmware_has_feature(FW_FEATURE_OPAL))
99                 seq_printf(m, "firmware\t: OPAL v1\n");
100         else
101                 seq_printf(m, "firmware\t: BML\n");
102         of_node_put(root);
103 }
104
105 static void pnv_prepare_going_down(void)
106 {
107         /*
108          * Disable all notifiers from OPAL, we can't
109          * service interrupts anymore anyway
110          */
111         opal_notifier_disable();
112
113         /* Soft disable interrupts */
114         local_irq_disable();
115
116         /*
117          * Return secondary CPUs to firwmare if a flash update
118          * is pending otherwise we will get all sort of error
119          * messages about CPU being stuck etc.. This will also
120          * have the side effect of hard disabling interrupts so
121          * past this point, the kernel is effectively dead.
122          */
123         opal_flash_term_callback();
124 }
125
126 static void  __noreturn pnv_restart(char *cmd)
127 {
128         long rc = OPAL_BUSY;
129
130         pnv_prepare_going_down();
131
132         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
133                 rc = opal_cec_reboot();
134                 if (rc == OPAL_BUSY_EVENT)
135                         opal_poll_events(NULL);
136                 else
137                         mdelay(10);
138         }
139         for (;;)
140                 opal_poll_events(NULL);
141 }
142
143 static void __noreturn pnv_power_off(void)
144 {
145         long rc = OPAL_BUSY;
146
147         pnv_prepare_going_down();
148
149         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
150                 rc = opal_cec_power_down(0);
151                 if (rc == OPAL_BUSY_EVENT)
152                         opal_poll_events(NULL);
153                 else
154                         mdelay(10);
155         }
156         for (;;)
157                 opal_poll_events(NULL);
158 }
159
160 static void __noreturn pnv_halt(void)
161 {
162         pnv_power_off();
163 }
164
165 static void pnv_progress(char *s, unsigned short hex)
166 {
167 }
168
169 static int pnv_dma_set_mask(struct device *dev, u64 dma_mask)
170 {
171         if (dev_is_pci(dev))
172                 return pnv_pci_dma_set_mask(to_pci_dev(dev), dma_mask);
173         return __dma_set_mask(dev, dma_mask);
174 }
175
176 static u64 pnv_dma_get_required_mask(struct device *dev)
177 {
178         if (dev_is_pci(dev))
179                 return pnv_pci_dma_get_required_mask(to_pci_dev(dev));
180
181         return __dma_get_required_mask(dev);
182 }
183
184 static void pnv_shutdown(void)
185 {
186         /* Let the PCI code clear up IODA tables */
187         pnv_pci_shutdown();
188
189         /*
190          * Stop OPAL activity: Unregister all OPAL interrupts so they
191          * don't fire up while we kexec and make sure all potentially
192          * DMA'ing ops are complete (such as dump retrieval).
193          */
194         opal_shutdown();
195 }
196
197 #ifdef CONFIG_KEXEC
198 static void pnv_kexec_wait_secondaries_down(void)
199 {
200         int my_cpu, i, notified = -1;
201
202         my_cpu = get_cpu();
203
204         for_each_online_cpu(i) {
205                 uint8_t status;
206                 int64_t rc;
207
208                 if (i == my_cpu)
209                         continue;
210
211                 for (;;) {
212                         rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
213                                                    &status);
214                         if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
215                                 break;
216                         barrier();
217                         if (i != notified) {
218                                 printk(KERN_INFO "kexec: waiting for cpu %d "
219                                        "(physical %d) to enter OPAL\n",
220                                        i, paca[i].hw_cpu_id);
221                                 notified = i;
222                         }
223                 }
224         }
225 }
226
227 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
228 {
229         xics_kexec_teardown_cpu(secondary);
230
231         /* On OPAL v3, we return all CPUs to firmware */
232
233         if (!firmware_has_feature(FW_FEATURE_OPALv3))
234                 return;
235
236         if (secondary) {
237                 /* Return secondary CPUs to firmware on OPAL v3 */
238                 mb();
239                 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
240                 mb();
241
242                 /* Return the CPU to OPAL */
243                 opal_return_cpu();
244         } else if (crash_shutdown) {
245                 /*
246                  * On crash, we don't wait for secondaries to go
247                  * down as they might be unreachable or hung, so
248                  * instead we just wait a bit and move on.
249                  */
250                 mdelay(1);
251         } else {
252                 /* Primary waits for the secondaries to have reached OPAL */
253                 pnv_kexec_wait_secondaries_down();
254         }
255 }
256 #endif /* CONFIG_KEXEC */
257
258 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
259 static unsigned long pnv_memory_block_size(void)
260 {
261         return 256UL * 1024 * 1024;
262 }
263 #endif
264
265 static void __init pnv_setup_machdep_opal(void)
266 {
267         ppc_md.get_boot_time = opal_get_boot_time;
268         ppc_md.restart = pnv_restart;
269         pm_power_off = pnv_power_off;
270         ppc_md.halt = pnv_halt;
271         ppc_md.machine_check_exception = opal_machine_check;
272         ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
273         ppc_md.hmi_exception_early = opal_hmi_exception_early;
274         ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
275 }
276
277 #ifdef CONFIG_PPC_POWERNV_RTAS
278 static void __init pnv_setup_machdep_rtas(void)
279 {
280         if (rtas_token("get-time-of-day") != RTAS_UNKNOWN_SERVICE) {
281                 ppc_md.get_boot_time = rtas_get_boot_time;
282                 ppc_md.get_rtc_time = rtas_get_rtc_time;
283                 ppc_md.set_rtc_time = rtas_set_rtc_time;
284         }
285         ppc_md.restart = rtas_restart;
286         pm_power_off = rtas_power_off;
287         ppc_md.halt = rtas_halt;
288 }
289 #endif /* CONFIG_PPC_POWERNV_RTAS */
290
291 static int __init pnv_probe(void)
292 {
293         unsigned long root = of_get_flat_dt_root();
294
295         if (!of_flat_dt_is_compatible(root, "ibm,powernv"))
296                 return 0;
297
298         hpte_init_native();
299
300         if (firmware_has_feature(FW_FEATURE_OPAL))
301                 pnv_setup_machdep_opal();
302 #ifdef CONFIG_PPC_POWERNV_RTAS
303         else if (rtas.base)
304                 pnv_setup_machdep_rtas();
305 #endif /* CONFIG_PPC_POWERNV_RTAS */
306
307         pr_debug("PowerNV detected !\n");
308
309         return 1;
310 }
311
312 /*
313  * Returns the cpu frequency for 'cpu' in Hz. This is used by
314  * /proc/cpuinfo
315  */
316 static unsigned long pnv_get_proc_freq(unsigned int cpu)
317 {
318         unsigned long ret_freq;
319
320         ret_freq = cpufreq_quick_get(cpu) * 1000ul;
321
322         /*
323          * If the backend cpufreq driver does not exist,
324          * then fallback to old way of reporting the clockrate.
325          */
326         if (!ret_freq)
327                 ret_freq = ppc_proc_freq;
328         return ret_freq;
329 }
330
331 define_machine(powernv) {
332         .name                   = "PowerNV",
333         .probe                  = pnv_probe,
334         .init_early             = pnv_init_early,
335         .setup_arch             = pnv_setup_arch,
336         .init_IRQ               = pnv_init_IRQ,
337         .show_cpuinfo           = pnv_show_cpuinfo,
338         .get_proc_freq          = pnv_get_proc_freq,
339         .progress               = pnv_progress,
340         .machine_shutdown       = pnv_shutdown,
341         .power_save             = power7_idle,
342         .calibrate_decr         = generic_calibrate_decr,
343         .dma_set_mask           = pnv_dma_set_mask,
344         .dma_get_required_mask  = pnv_dma_get_required_mask,
345 #ifdef CONFIG_KEXEC
346         .kexec_cpu_down         = pnv_kexec_cpu_down,
347 #endif
348 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
349         .memory_block_size      = pnv_memory_block_size,
350 #endif
351 };