tty: serial: samsung: drop uart_port->lock before calling tty_flip_buffer_push()
[firefly-linux-kernel-4.4.55.git] / arch / sparc / kernel / ds.c
1 /* ds.c: Domain Services driver for Logical Domains
2  *
3  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4  */
5
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/string.h>
10 #include <linux/slab.h>
11 #include <linux/sched.h>
12 #include <linux/delay.h>
13 #include <linux/mutex.h>
14 #include <linux/kthread.h>
15 #include <linux/reboot.h>
16 #include <linux/cpu.h>
17
18 #include <asm/hypervisor.h>
19 #include <asm/ldc.h>
20 #include <asm/vio.h>
21 #include <asm/mdesc.h>
22 #include <asm/head.h>
23 #include <asm/irq.h>
24
25 #include "kernel.h"
26
27 #define DRV_MODULE_NAME         "ds"
28 #define PFX DRV_MODULE_NAME     ": "
29 #define DRV_MODULE_VERSION      "1.0"
30 #define DRV_MODULE_RELDATE      "Jul 11, 2007"
31
32 static char version[] =
33         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
34 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
35 MODULE_DESCRIPTION("Sun LDOM domain services driver");
36 MODULE_LICENSE("GPL");
37 MODULE_VERSION(DRV_MODULE_VERSION);
38
39 struct ds_msg_tag {
40         __u32                   type;
41 #define DS_INIT_REQ             0x00
42 #define DS_INIT_ACK             0x01
43 #define DS_INIT_NACK            0x02
44 #define DS_REG_REQ              0x03
45 #define DS_REG_ACK              0x04
46 #define DS_REG_NACK             0x05
47 #define DS_UNREG_REQ            0x06
48 #define DS_UNREG_ACK            0x07
49 #define DS_UNREG_NACK           0x08
50 #define DS_DATA                 0x09
51 #define DS_NACK                 0x0a
52
53         __u32                   len;
54 };
55
56 /* Result codes */
57 #define DS_OK                   0x00
58 #define DS_REG_VER_NACK         0x01
59 #define DS_REG_DUP              0x02
60 #define DS_INV_HDL              0x03
61 #define DS_TYPE_UNKNOWN         0x04
62
63 struct ds_version {
64         __u16                   major;
65         __u16                   minor;
66 };
67
68 struct ds_ver_req {
69         struct ds_msg_tag       tag;
70         struct ds_version       ver;
71 };
72
73 struct ds_ver_ack {
74         struct ds_msg_tag       tag;
75         __u16                   minor;
76 };
77
78 struct ds_ver_nack {
79         struct ds_msg_tag       tag;
80         __u16                   major;
81 };
82
83 struct ds_reg_req {
84         struct ds_msg_tag       tag;
85         __u64                   handle;
86         __u16                   major;
87         __u16                   minor;
88         char                    svc_id[0];
89 };
90
91 struct ds_reg_ack {
92         struct ds_msg_tag       tag;
93         __u64                   handle;
94         __u16                   minor;
95 };
96
97 struct ds_reg_nack {
98         struct ds_msg_tag       tag;
99         __u64                   handle;
100         __u16                   major;
101 };
102
103 struct ds_unreg_req {
104         struct ds_msg_tag       tag;
105         __u64                   handle;
106 };
107
108 struct ds_unreg_ack {
109         struct ds_msg_tag       tag;
110         __u64                   handle;
111 };
112
113 struct ds_unreg_nack {
114         struct ds_msg_tag       tag;
115         __u64                   handle;
116 };
117
118 struct ds_data {
119         struct ds_msg_tag       tag;
120         __u64                   handle;
121 };
122
123 struct ds_data_nack {
124         struct ds_msg_tag       tag;
125         __u64                   handle;
126         __u64                   result;
127 };
128
129 struct ds_info;
130 struct ds_cap_state {
131         __u64                   handle;
132
133         void                    (*data)(struct ds_info *dp,
134                                         struct ds_cap_state *cp,
135                                         void *buf, int len);
136
137         const char              *service_id;
138
139         u8                      state;
140 #define CAP_STATE_UNKNOWN       0x00
141 #define CAP_STATE_REG_SENT      0x01
142 #define CAP_STATE_REGISTERED    0x02
143 };
144
145 static void md_update_data(struct ds_info *dp, struct ds_cap_state *cp,
146                            void *buf, int len);
147 static void domain_shutdown_data(struct ds_info *dp,
148                                  struct ds_cap_state *cp,
149                                  void *buf, int len);
150 static void domain_panic_data(struct ds_info *dp,
151                               struct ds_cap_state *cp,
152                               void *buf, int len);
153 #ifdef CONFIG_HOTPLUG_CPU
154 static void dr_cpu_data(struct ds_info *dp,
155                         struct ds_cap_state *cp,
156                         void *buf, int len);
157 #endif
158 static void ds_pri_data(struct ds_info *dp,
159                         struct ds_cap_state *cp,
160                         void *buf, int len);
161 static void ds_var_data(struct ds_info *dp,
162                         struct ds_cap_state *cp,
163                         void *buf, int len);
164
165 static struct ds_cap_state ds_states_template[] = {
166         {
167                 .service_id     = "md-update",
168                 .data           = md_update_data,
169         },
170         {
171                 .service_id     = "domain-shutdown",
172                 .data           = domain_shutdown_data,
173         },
174         {
175                 .service_id     = "domain-panic",
176                 .data           = domain_panic_data,
177         },
178 #ifdef CONFIG_HOTPLUG_CPU
179         {
180                 .service_id     = "dr-cpu",
181                 .data           = dr_cpu_data,
182         },
183 #endif
184         {
185                 .service_id     = "pri",
186                 .data           = ds_pri_data,
187         },
188         {
189                 .service_id     = "var-config",
190                 .data           = ds_var_data,
191         },
192         {
193                 .service_id     = "var-config-backup",
194                 .data           = ds_var_data,
195         },
196 };
197
198 static DEFINE_SPINLOCK(ds_lock);
199
200 struct ds_info {
201         struct ldc_channel      *lp;
202         u8                      hs_state;
203 #define DS_HS_START             0x01
204 #define DS_HS_DONE              0x02
205
206         u64                     id;
207
208         void                    *rcv_buf;
209         int                     rcv_buf_len;
210
211         struct ds_cap_state     *ds_states;
212         int                     num_ds_states;
213
214         struct ds_info          *next;
215 };
216
217 static struct ds_info *ds_info_list;
218
219 static struct ds_cap_state *find_cap(struct ds_info *dp, u64 handle)
220 {
221         unsigned int index = handle >> 32;
222
223         if (index >= dp->num_ds_states)
224                 return NULL;
225         return &dp->ds_states[index];
226 }
227
228 static struct ds_cap_state *find_cap_by_string(struct ds_info *dp,
229                                                const char *name)
230 {
231         int i;
232
233         for (i = 0; i < dp->num_ds_states; i++) {
234                 if (strcmp(dp->ds_states[i].service_id, name))
235                         continue;
236
237                 return &dp->ds_states[i];
238         }
239         return NULL;
240 }
241
242 static int __ds_send(struct ldc_channel *lp, void *data, int len)
243 {
244         int err, limit = 1000;
245
246         err = -EINVAL;
247         while (limit-- > 0) {
248                 err = ldc_write(lp, data, len);
249                 if (!err || (err != -EAGAIN))
250                         break;
251                 udelay(1);
252         }
253
254         return err;
255 }
256
257 static int ds_send(struct ldc_channel *lp, void *data, int len)
258 {
259         unsigned long flags;
260         int err;
261
262         spin_lock_irqsave(&ds_lock, flags);
263         err = __ds_send(lp, data, len);
264         spin_unlock_irqrestore(&ds_lock, flags);
265
266         return err;
267 }
268
269 struct ds_md_update_req {
270         __u64                           req_num;
271 };
272
273 struct ds_md_update_res {
274         __u64                           req_num;
275         __u32                           result;
276 };
277
278 static void md_update_data(struct ds_info *dp,
279                            struct ds_cap_state *cp,
280                            void *buf, int len)
281 {
282         struct ldc_channel *lp = dp->lp;
283         struct ds_data *dpkt = buf;
284         struct ds_md_update_req *rp;
285         struct {
286                 struct ds_data          data;
287                 struct ds_md_update_res res;
288         } pkt;
289
290         rp = (struct ds_md_update_req *) (dpkt + 1);
291
292         printk(KERN_INFO "ds-%llu: Machine description update.\n", dp->id);
293
294         mdesc_update();
295
296         memset(&pkt, 0, sizeof(pkt));
297         pkt.data.tag.type = DS_DATA;
298         pkt.data.tag.len = sizeof(pkt) - sizeof(struct ds_msg_tag);
299         pkt.data.handle = cp->handle;
300         pkt.res.req_num = rp->req_num;
301         pkt.res.result = DS_OK;
302
303         ds_send(lp, &pkt, sizeof(pkt));
304 }
305
306 struct ds_shutdown_req {
307         __u64                           req_num;
308         __u32                           ms_delay;
309 };
310
311 struct ds_shutdown_res {
312         __u64                           req_num;
313         __u32                           result;
314         char                            reason[1];
315 };
316
317 static void domain_shutdown_data(struct ds_info *dp,
318                                  struct ds_cap_state *cp,
319                                  void *buf, int len)
320 {
321         struct ldc_channel *lp = dp->lp;
322         struct ds_data *dpkt = buf;
323         struct ds_shutdown_req *rp;
324         struct {
325                 struct ds_data          data;
326                 struct ds_shutdown_res  res;
327         } pkt;
328
329         rp = (struct ds_shutdown_req *) (dpkt + 1);
330
331         printk(KERN_ALERT "ds-%llu: Shutdown request from "
332                "LDOM manager received.\n", dp->id);
333
334         memset(&pkt, 0, sizeof(pkt));
335         pkt.data.tag.type = DS_DATA;
336         pkt.data.tag.len = sizeof(pkt) - sizeof(struct ds_msg_tag);
337         pkt.data.handle = cp->handle;
338         pkt.res.req_num = rp->req_num;
339         pkt.res.result = DS_OK;
340         pkt.res.reason[0] = 0;
341
342         ds_send(lp, &pkt, sizeof(pkt));
343
344         orderly_poweroff(true);
345 }
346
347 struct ds_panic_req {
348         __u64                           req_num;
349 };
350
351 struct ds_panic_res {
352         __u64                           req_num;
353         __u32                           result;
354         char                            reason[1];
355 };
356
357 static void domain_panic_data(struct ds_info *dp,
358                               struct ds_cap_state *cp,
359                               void *buf, int len)
360 {
361         struct ldc_channel *lp = dp->lp;
362         struct ds_data *dpkt = buf;
363         struct ds_panic_req *rp;
364         struct {
365                 struct ds_data          data;
366                 struct ds_panic_res     res;
367         } pkt;
368
369         rp = (struct ds_panic_req *) (dpkt + 1);
370
371         printk(KERN_ALERT "ds-%llu: Panic request from "
372                "LDOM manager received.\n", dp->id);
373
374         memset(&pkt, 0, sizeof(pkt));
375         pkt.data.tag.type = DS_DATA;
376         pkt.data.tag.len = sizeof(pkt) - sizeof(struct ds_msg_tag);
377         pkt.data.handle = cp->handle;
378         pkt.res.req_num = rp->req_num;
379         pkt.res.result = DS_OK;
380         pkt.res.reason[0] = 0;
381
382         ds_send(lp, &pkt, sizeof(pkt));
383
384         panic("PANIC requested by LDOM manager.");
385 }
386
387 #ifdef CONFIG_HOTPLUG_CPU
388 struct dr_cpu_tag {
389         __u64                           req_num;
390         __u32                           type;
391 #define DR_CPU_CONFIGURE                0x43
392 #define DR_CPU_UNCONFIGURE              0x55
393 #define DR_CPU_FORCE_UNCONFIGURE        0x46
394 #define DR_CPU_STATUS                   0x53
395
396 /* Responses */
397 #define DR_CPU_OK                       0x6f
398 #define DR_CPU_ERROR                    0x65
399
400         __u32                           num_records;
401 };
402
403 struct dr_cpu_resp_entry {
404         __u32                           cpu;
405         __u32                           result;
406 #define DR_CPU_RES_OK                   0x00
407 #define DR_CPU_RES_FAILURE              0x01
408 #define DR_CPU_RES_BLOCKED              0x02
409 #define DR_CPU_RES_CPU_NOT_RESPONDING   0x03
410 #define DR_CPU_RES_NOT_IN_MD            0x04
411
412         __u32                           stat;
413 #define DR_CPU_STAT_NOT_PRESENT         0x00
414 #define DR_CPU_STAT_UNCONFIGURED        0x01
415 #define DR_CPU_STAT_CONFIGURED          0x02
416
417         __u32                           str_off;
418 };
419
420 static void __dr_cpu_send_error(struct ds_info *dp,
421                                 struct ds_cap_state *cp,
422                                 struct ds_data *data)
423 {
424         struct dr_cpu_tag *tag = (struct dr_cpu_tag *) (data + 1);
425         struct {
426                 struct ds_data          data;
427                 struct dr_cpu_tag       tag;
428         } pkt;
429         int msg_len;
430
431         memset(&pkt, 0, sizeof(pkt));
432         pkt.data.tag.type = DS_DATA;
433         pkt.data.handle = cp->handle;
434         pkt.tag.req_num = tag->req_num;
435         pkt.tag.type = DR_CPU_ERROR;
436         pkt.tag.num_records = 0;
437
438         msg_len = (sizeof(struct ds_data) +
439                    sizeof(struct dr_cpu_tag));
440
441         pkt.data.tag.len = msg_len - sizeof(struct ds_msg_tag);
442
443         __ds_send(dp->lp, &pkt, msg_len);
444 }
445
446 static void dr_cpu_send_error(struct ds_info *dp,
447                               struct ds_cap_state *cp,
448                               struct ds_data *data)
449 {
450         unsigned long flags;
451
452         spin_lock_irqsave(&ds_lock, flags);
453         __dr_cpu_send_error(dp, cp, data);
454         spin_unlock_irqrestore(&ds_lock, flags);
455 }
456
457 #define CPU_SENTINEL    0xffffffff
458
459 static void purge_dups(u32 *list, u32 num_ents)
460 {
461         unsigned int i;
462
463         for (i = 0; i < num_ents; i++) {
464                 u32 cpu = list[i];
465                 unsigned int j;
466
467                 if (cpu == CPU_SENTINEL)
468                         continue;
469
470                 for (j = i + 1; j < num_ents; j++) {
471                         if (list[j] == cpu)
472                                 list[j] = CPU_SENTINEL;
473                 }
474         }
475 }
476
477 static int dr_cpu_size_response(int ncpus)
478 {
479         return (sizeof(struct ds_data) +
480                 sizeof(struct dr_cpu_tag) +
481                 (sizeof(struct dr_cpu_resp_entry) * ncpus));
482 }
483
484 static void dr_cpu_init_response(struct ds_data *resp, u64 req_num,
485                                  u64 handle, int resp_len, int ncpus,
486                                  cpumask_t *mask, u32 default_stat)
487 {
488         struct dr_cpu_resp_entry *ent;
489         struct dr_cpu_tag *tag;
490         int i, cpu;
491
492         tag = (struct dr_cpu_tag *) (resp + 1);
493         ent = (struct dr_cpu_resp_entry *) (tag + 1);
494
495         resp->tag.type = DS_DATA;
496         resp->tag.len = resp_len - sizeof(struct ds_msg_tag);
497         resp->handle = handle;
498         tag->req_num = req_num;
499         tag->type = DR_CPU_OK;
500         tag->num_records = ncpus;
501
502         i = 0;
503         for_each_cpu(cpu, mask) {
504                 ent[i].cpu = cpu;
505                 ent[i].result = DR_CPU_RES_OK;
506                 ent[i].stat = default_stat;
507                 i++;
508         }
509         BUG_ON(i != ncpus);
510 }
511
512 static void dr_cpu_mark(struct ds_data *resp, int cpu, int ncpus,
513                         u32 res, u32 stat)
514 {
515         struct dr_cpu_resp_entry *ent;
516         struct dr_cpu_tag *tag;
517         int i;
518
519         tag = (struct dr_cpu_tag *) (resp + 1);
520         ent = (struct dr_cpu_resp_entry *) (tag + 1);
521
522         for (i = 0; i < ncpus; i++) {
523                 if (ent[i].cpu != cpu)
524                         continue;
525                 ent[i].result = res;
526                 ent[i].stat = stat;
527                 break;
528         }
529 }
530
531 static int __cpuinit dr_cpu_configure(struct ds_info *dp,
532                                       struct ds_cap_state *cp,
533                                       u64 req_num,
534                                       cpumask_t *mask)
535 {
536         struct ds_data *resp;
537         int resp_len, ncpus, cpu;
538         unsigned long flags;
539
540         ncpus = cpumask_weight(mask);
541         resp_len = dr_cpu_size_response(ncpus);
542         resp = kzalloc(resp_len, GFP_KERNEL);
543         if (!resp)
544                 return -ENOMEM;
545
546         dr_cpu_init_response(resp, req_num, cp->handle,
547                              resp_len, ncpus, mask,
548                              DR_CPU_STAT_CONFIGURED);
549
550         mdesc_populate_present_mask(mask);
551         mdesc_fill_in_cpu_data(mask);
552
553         for_each_cpu(cpu, mask) {
554                 int err;
555
556                 printk(KERN_INFO "ds-%llu: Starting cpu %d...\n",
557                        dp->id, cpu);
558                 err = cpu_up(cpu);
559                 if (err) {
560                         __u32 res = DR_CPU_RES_FAILURE;
561                         __u32 stat = DR_CPU_STAT_UNCONFIGURED;
562
563                         if (!cpu_present(cpu)) {
564                                 /* CPU not present in MD */
565                                 res = DR_CPU_RES_NOT_IN_MD;
566                                 stat = DR_CPU_STAT_NOT_PRESENT;
567                         } else if (err == -ENODEV) {
568                                 /* CPU did not call in successfully */
569                                 res = DR_CPU_RES_CPU_NOT_RESPONDING;
570                         }
571
572                         printk(KERN_INFO "ds-%llu: CPU startup failed err=%d\n",
573                                dp->id, err);
574                         dr_cpu_mark(resp, cpu, ncpus, res, stat);
575                 }
576         }
577
578         spin_lock_irqsave(&ds_lock, flags);
579         __ds_send(dp->lp, resp, resp_len);
580         spin_unlock_irqrestore(&ds_lock, flags);
581
582         kfree(resp);
583
584         /* Redistribute IRQs, taking into account the new cpus.  */
585         fixup_irqs();
586
587         return 0;
588 }
589
590 static int dr_cpu_unconfigure(struct ds_info *dp,
591                               struct ds_cap_state *cp,
592                               u64 req_num,
593                               cpumask_t *mask)
594 {
595         struct ds_data *resp;
596         int resp_len, ncpus, cpu;
597         unsigned long flags;
598
599         ncpus = cpumask_weight(mask);
600         resp_len = dr_cpu_size_response(ncpus);
601         resp = kzalloc(resp_len, GFP_KERNEL);
602         if (!resp)
603                 return -ENOMEM;
604
605         dr_cpu_init_response(resp, req_num, cp->handle,
606                              resp_len, ncpus, mask,
607                              DR_CPU_STAT_UNCONFIGURED);
608
609         for_each_cpu(cpu, mask) {
610                 int err;
611
612                 printk(KERN_INFO "ds-%llu: Shutting down cpu %d...\n",
613                        dp->id, cpu);
614                 err = cpu_down(cpu);
615                 if (err)
616                         dr_cpu_mark(resp, cpu, ncpus,
617                                     DR_CPU_RES_FAILURE,
618                                     DR_CPU_STAT_CONFIGURED);
619         }
620
621         spin_lock_irqsave(&ds_lock, flags);
622         __ds_send(dp->lp, resp, resp_len);
623         spin_unlock_irqrestore(&ds_lock, flags);
624
625         kfree(resp);
626
627         return 0;
628 }
629
630 static void __cpuinit dr_cpu_data(struct ds_info *dp,
631                                   struct ds_cap_state *cp,
632                                   void *buf, int len)
633 {
634         struct ds_data *data = buf;
635         struct dr_cpu_tag *tag = (struct dr_cpu_tag *) (data + 1);
636         u32 *cpu_list = (u32 *) (tag + 1);
637         u64 req_num = tag->req_num;
638         cpumask_t mask;
639         unsigned int i;
640         int err;
641
642         switch (tag->type) {
643         case DR_CPU_CONFIGURE:
644         case DR_CPU_UNCONFIGURE:
645         case DR_CPU_FORCE_UNCONFIGURE:
646                 break;
647
648         default:
649                 dr_cpu_send_error(dp, cp, data);
650                 return;
651         }
652
653         purge_dups(cpu_list, tag->num_records);
654
655         cpumask_clear(&mask);
656         for (i = 0; i < tag->num_records; i++) {
657                 if (cpu_list[i] == CPU_SENTINEL)
658                         continue;
659
660                 if (cpu_list[i] < nr_cpu_ids)
661                         cpumask_set_cpu(cpu_list[i], &mask);
662         }
663
664         if (tag->type == DR_CPU_CONFIGURE)
665                 err = dr_cpu_configure(dp, cp, req_num, &mask);
666         else
667                 err = dr_cpu_unconfigure(dp, cp, req_num, &mask);
668
669         if (err)
670                 dr_cpu_send_error(dp, cp, data);
671 }
672 #endif /* CONFIG_HOTPLUG_CPU */
673
674 struct ds_pri_msg {
675         __u64                           req_num;
676         __u64                           type;
677 #define DS_PRI_REQUEST                  0x00
678 #define DS_PRI_DATA                     0x01
679 #define DS_PRI_UPDATE                   0x02
680 };
681
682 static void ds_pri_data(struct ds_info *dp,
683                         struct ds_cap_state *cp,
684                         void *buf, int len)
685 {
686         struct ds_data *dpkt = buf;
687         struct ds_pri_msg *rp;
688
689         rp = (struct ds_pri_msg *) (dpkt + 1);
690
691         printk(KERN_INFO "ds-%llu: PRI REQ [%llx:%llx], len=%d\n",
692                dp->id, rp->req_num, rp->type, len);
693 }
694
695 struct ds_var_hdr {
696         __u32                           type;
697 #define DS_VAR_SET_REQ                  0x00
698 #define DS_VAR_DELETE_REQ               0x01
699 #define DS_VAR_SET_RESP                 0x02
700 #define DS_VAR_DELETE_RESP              0x03
701 };
702
703 struct ds_var_set_msg {
704         struct ds_var_hdr               hdr;
705         char                            name_and_value[0];
706 };
707
708 struct ds_var_delete_msg {
709         struct ds_var_hdr               hdr;
710         char                            name[0];
711 };
712
713 struct ds_var_resp {
714         struct ds_var_hdr               hdr;
715         __u32                           result;
716 #define DS_VAR_SUCCESS                  0x00
717 #define DS_VAR_NO_SPACE                 0x01
718 #define DS_VAR_INVALID_VAR              0x02
719 #define DS_VAR_INVALID_VAL              0x03
720 #define DS_VAR_NOT_PRESENT              0x04
721 };
722
723 static DEFINE_MUTEX(ds_var_mutex);
724 static int ds_var_doorbell;
725 static int ds_var_response;
726
727 static void ds_var_data(struct ds_info *dp,
728                         struct ds_cap_state *cp,
729                         void *buf, int len)
730 {
731         struct ds_data *dpkt = buf;
732         struct ds_var_resp *rp;
733
734         rp = (struct ds_var_resp *) (dpkt + 1);
735
736         if (rp->hdr.type != DS_VAR_SET_RESP &&
737             rp->hdr.type != DS_VAR_DELETE_RESP)
738                 return;
739
740         ds_var_response = rp->result;
741         wmb();
742         ds_var_doorbell = 1;
743 }
744
745 void ldom_set_var(const char *var, const char *value)
746 {
747         struct ds_cap_state *cp;
748         struct ds_info *dp;
749         unsigned long flags;
750
751         spin_lock_irqsave(&ds_lock, flags);
752         cp = NULL;
753         for (dp = ds_info_list; dp; dp = dp->next) {
754                 struct ds_cap_state *tmp;
755
756                 tmp = find_cap_by_string(dp, "var-config");
757                 if (tmp && tmp->state == CAP_STATE_REGISTERED) {
758                         cp = tmp;
759                         break;
760                 }
761         }
762         if (!cp) {
763                 for (dp = ds_info_list; dp; dp = dp->next) {
764                         struct ds_cap_state *tmp;
765
766                         tmp = find_cap_by_string(dp, "var-config-backup");
767                         if (tmp && tmp->state == CAP_STATE_REGISTERED) {
768                                 cp = tmp;
769                                 break;
770                         }
771                 }
772         }
773         spin_unlock_irqrestore(&ds_lock, flags);
774
775         if (cp) {
776                 union {
777                         struct {
778                                 struct ds_data          data;
779                                 struct ds_var_set_msg   msg;
780                         } header;
781                         char                    all[512];
782                 } pkt;
783                 char  *base, *p;
784                 int msg_len, loops;
785
786                 memset(&pkt, 0, sizeof(pkt));
787                 pkt.header.data.tag.type = DS_DATA;
788                 pkt.header.data.handle = cp->handle;
789                 pkt.header.msg.hdr.type = DS_VAR_SET_REQ;
790                 base = p = &pkt.header.msg.name_and_value[0];
791                 strcpy(p, var);
792                 p += strlen(var) + 1;
793                 strcpy(p, value);
794                 p += strlen(value) + 1;
795
796                 msg_len = (sizeof(struct ds_data) +
797                            sizeof(struct ds_var_set_msg) +
798                            (p - base));
799                 msg_len = (msg_len + 3) & ~3;
800                 pkt.header.data.tag.len = msg_len - sizeof(struct ds_msg_tag);
801
802                 mutex_lock(&ds_var_mutex);
803
804                 spin_lock_irqsave(&ds_lock, flags);
805                 ds_var_doorbell = 0;
806                 ds_var_response = -1;
807
808                 __ds_send(dp->lp, &pkt, msg_len);
809                 spin_unlock_irqrestore(&ds_lock, flags);
810
811                 loops = 1000;
812                 while (ds_var_doorbell == 0) {
813                         if (loops-- < 0)
814                                 break;
815                         barrier();
816                         udelay(100);
817                 }
818
819                 mutex_unlock(&ds_var_mutex);
820
821                 if (ds_var_doorbell == 0 ||
822                     ds_var_response != DS_VAR_SUCCESS)
823                         printk(KERN_ERR "ds-%llu: var-config [%s:%s] "
824                                "failed, response(%d).\n",
825                                dp->id, var, value,
826                                ds_var_response);
827         } else {
828                 printk(KERN_ERR PFX "var-config not registered so "
829                        "could not set (%s) variable to (%s).\n",
830                        var, value);
831         }
832 }
833
834 static char full_boot_str[256] __attribute__((aligned(32)));
835 static int reboot_data_supported;
836
837 void ldom_reboot(const char *boot_command)
838 {
839         /* Don't bother with any of this if the boot_command
840          * is empty.
841          */
842         if (boot_command && strlen(boot_command)) {
843                 unsigned long len;
844
845                 strcpy(full_boot_str, "boot ");
846                 strlcpy(full_boot_str + strlen("boot "), boot_command,
847                         sizeof(full_boot_str + strlen("boot ")));
848                 len = strlen(full_boot_str);
849
850                 if (reboot_data_supported) {
851                         unsigned long ra = kimage_addr_to_ra(full_boot_str);
852                         unsigned long hv_ret;
853
854                         hv_ret = sun4v_reboot_data_set(ra, len);
855                         if (hv_ret != HV_EOK)
856                                 pr_err("SUN4V: Unable to set reboot data "
857                                        "hv_ret=%lu\n", hv_ret);
858                 } else {
859                         ldom_set_var("reboot-command", full_boot_str);
860                 }
861         }
862         sun4v_mach_sir();
863 }
864
865 void ldom_power_off(void)
866 {
867         sun4v_mach_exit(0);
868 }
869
870 static void ds_conn_reset(struct ds_info *dp)
871 {
872         printk(KERN_ERR "ds-%llu: ds_conn_reset() from %pf\n",
873                dp->id, __builtin_return_address(0));
874 }
875
876 static int register_services(struct ds_info *dp)
877 {
878         struct ldc_channel *lp = dp->lp;
879         int i;
880
881         for (i = 0; i < dp->num_ds_states; i++) {
882                 struct {
883                         struct ds_reg_req req;
884                         u8 id_buf[256];
885                 } pbuf;
886                 struct ds_cap_state *cp = &dp->ds_states[i];
887                 int err, msg_len;
888                 u64 new_count;
889
890                 if (cp->state == CAP_STATE_REGISTERED)
891                         continue;
892
893                 new_count = sched_clock() & 0xffffffff;
894                 cp->handle = ((u64) i << 32) | new_count;
895
896                 msg_len = (sizeof(struct ds_reg_req) +
897                            strlen(cp->service_id));
898
899                 memset(&pbuf, 0, sizeof(pbuf));
900                 pbuf.req.tag.type = DS_REG_REQ;
901                 pbuf.req.tag.len = (msg_len - sizeof(struct ds_msg_tag));
902                 pbuf.req.handle = cp->handle;
903                 pbuf.req.major = 1;
904                 pbuf.req.minor = 0;
905                 strcpy(pbuf.req.svc_id, cp->service_id);
906
907                 err = __ds_send(lp, &pbuf, msg_len);
908                 if (err > 0)
909                         cp->state = CAP_STATE_REG_SENT;
910         }
911         return 0;
912 }
913
914 static int ds_handshake(struct ds_info *dp, struct ds_msg_tag *pkt)
915 {
916
917         if (dp->hs_state == DS_HS_START) {
918                 if (pkt->type != DS_INIT_ACK)
919                         goto conn_reset;
920
921                 dp->hs_state = DS_HS_DONE;
922
923                 return register_services(dp);
924         }
925
926         if (dp->hs_state != DS_HS_DONE)
927                 goto conn_reset;
928
929         if (pkt->type == DS_REG_ACK) {
930                 struct ds_reg_ack *ap = (struct ds_reg_ack *) pkt;
931                 struct ds_cap_state *cp = find_cap(dp, ap->handle);
932
933                 if (!cp) {
934                         printk(KERN_ERR "ds-%llu: REG ACK for unknown "
935                                "handle %llx\n", dp->id, ap->handle);
936                         return 0;
937                 }
938                 printk(KERN_INFO "ds-%llu: Registered %s service.\n",
939                        dp->id, cp->service_id);
940                 cp->state = CAP_STATE_REGISTERED;
941         } else if (pkt->type == DS_REG_NACK) {
942                 struct ds_reg_nack *np = (struct ds_reg_nack *) pkt;
943                 struct ds_cap_state *cp = find_cap(dp, np->handle);
944
945                 if (!cp) {
946                         printk(KERN_ERR "ds-%llu: REG NACK for "
947                                "unknown handle %llx\n",
948                                dp->id, np->handle);
949                         return 0;
950                 }
951                 cp->state = CAP_STATE_UNKNOWN;
952         }
953
954         return 0;
955
956 conn_reset:
957         ds_conn_reset(dp);
958         return -ECONNRESET;
959 }
960
961 static void __send_ds_nack(struct ds_info *dp, u64 handle)
962 {
963         struct ds_data_nack nack = {
964                 .tag = {
965                         .type = DS_NACK,
966                         .len = (sizeof(struct ds_data_nack) -
967                                 sizeof(struct ds_msg_tag)),
968                 },
969                 .handle = handle,
970                 .result = DS_INV_HDL,
971         };
972
973         __ds_send(dp->lp, &nack, sizeof(nack));
974 }
975
976 static LIST_HEAD(ds_work_list);
977 static DECLARE_WAIT_QUEUE_HEAD(ds_wait);
978
979 struct ds_queue_entry {
980         struct list_head                list;
981         struct ds_info                  *dp;
982         int                             req_len;
983         int                             __pad;
984         u64                             req[0];
985 };
986
987 static void process_ds_work(void)
988 {
989         struct ds_queue_entry *qp, *tmp;
990         unsigned long flags;
991         LIST_HEAD(todo);
992
993         spin_lock_irqsave(&ds_lock, flags);
994         list_splice_init(&ds_work_list, &todo);
995         spin_unlock_irqrestore(&ds_lock, flags);
996
997         list_for_each_entry_safe(qp, tmp, &todo, list) {
998                 struct ds_data *dpkt = (struct ds_data *) qp->req;
999                 struct ds_info *dp = qp->dp;
1000                 struct ds_cap_state *cp = find_cap(dp, dpkt->handle);
1001                 int req_len = qp->req_len;
1002
1003                 if (!cp) {
1004                         printk(KERN_ERR "ds-%llu: Data for unknown "
1005                                "handle %llu\n",
1006                                dp->id, dpkt->handle);
1007
1008                         spin_lock_irqsave(&ds_lock, flags);
1009                         __send_ds_nack(dp, dpkt->handle);
1010                         spin_unlock_irqrestore(&ds_lock, flags);
1011                 } else {
1012                         cp->data(dp, cp, dpkt, req_len);
1013                 }
1014
1015                 list_del(&qp->list);
1016                 kfree(qp);
1017         }
1018 }
1019
1020 static int ds_thread(void *__unused)
1021 {
1022         DEFINE_WAIT(wait);
1023
1024         while (1) {
1025                 prepare_to_wait(&ds_wait, &wait, TASK_INTERRUPTIBLE);
1026                 if (list_empty(&ds_work_list))
1027                         schedule();
1028                 finish_wait(&ds_wait, &wait);
1029
1030                 if (kthread_should_stop())
1031                         break;
1032
1033                 process_ds_work();
1034         }
1035
1036         return 0;
1037 }
1038
1039 static int ds_data(struct ds_info *dp, struct ds_msg_tag *pkt, int len)
1040 {
1041         struct ds_data *dpkt = (struct ds_data *) pkt;
1042         struct ds_queue_entry *qp;
1043
1044         qp = kmalloc(sizeof(struct ds_queue_entry) + len, GFP_ATOMIC);
1045         if (!qp) {
1046                 __send_ds_nack(dp, dpkt->handle);
1047         } else {
1048                 qp->dp = dp;
1049                 memcpy(&qp->req, pkt, len);
1050                 list_add_tail(&qp->list, &ds_work_list);
1051                 wake_up(&ds_wait);
1052         }
1053         return 0;
1054 }
1055
1056 static void ds_up(struct ds_info *dp)
1057 {
1058         struct ldc_channel *lp = dp->lp;
1059         struct ds_ver_req req;
1060         int err;
1061
1062         req.tag.type = DS_INIT_REQ;
1063         req.tag.len = sizeof(req) - sizeof(struct ds_msg_tag);
1064         req.ver.major = 1;
1065         req.ver.minor = 0;
1066
1067         err = __ds_send(lp, &req, sizeof(req));
1068         if (err > 0)
1069                 dp->hs_state = DS_HS_START;
1070 }
1071
1072 static void ds_reset(struct ds_info *dp)
1073 {
1074         int i;
1075
1076         dp->hs_state = 0;
1077
1078         for (i = 0; i < dp->num_ds_states; i++) {
1079                 struct ds_cap_state *cp = &dp->ds_states[i];
1080
1081                 cp->state = CAP_STATE_UNKNOWN;
1082         }
1083 }
1084
1085 static void ds_event(void *arg, int event)
1086 {
1087         struct ds_info *dp = arg;
1088         struct ldc_channel *lp = dp->lp;
1089         unsigned long flags;
1090         int err;
1091
1092         spin_lock_irqsave(&ds_lock, flags);
1093
1094         if (event == LDC_EVENT_UP) {
1095                 ds_up(dp);
1096                 spin_unlock_irqrestore(&ds_lock, flags);
1097                 return;
1098         }
1099
1100         if (event == LDC_EVENT_RESET) {
1101                 ds_reset(dp);
1102                 spin_unlock_irqrestore(&ds_lock, flags);
1103                 return;
1104         }
1105
1106         if (event != LDC_EVENT_DATA_READY) {
1107                 printk(KERN_WARNING "ds-%llu: Unexpected LDC event %d\n",
1108                        dp->id, event);
1109                 spin_unlock_irqrestore(&ds_lock, flags);
1110                 return;
1111         }
1112
1113         err = 0;
1114         while (1) {
1115                 struct ds_msg_tag *tag;
1116
1117                 err = ldc_read(lp, dp->rcv_buf, sizeof(*tag));
1118
1119                 if (unlikely(err < 0)) {
1120                         if (err == -ECONNRESET)
1121                                 ds_conn_reset(dp);
1122                         break;
1123                 }
1124                 if (err == 0)
1125                         break;
1126
1127                 tag = dp->rcv_buf;
1128                 err = ldc_read(lp, tag + 1, tag->len);
1129
1130                 if (unlikely(err < 0)) {
1131                         if (err == -ECONNRESET)
1132                                 ds_conn_reset(dp);
1133                         break;
1134                 }
1135                 if (err < tag->len)
1136                         break;
1137
1138                 if (tag->type < DS_DATA)
1139                         err = ds_handshake(dp, dp->rcv_buf);
1140                 else
1141                         err = ds_data(dp, dp->rcv_buf,
1142                                       sizeof(*tag) + err);
1143                 if (err == -ECONNRESET)
1144                         break;
1145         }
1146
1147         spin_unlock_irqrestore(&ds_lock, flags);
1148 }
1149
1150 static int ds_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1151 {
1152         static int ds_version_printed;
1153         struct ldc_channel_config ds_cfg = {
1154                 .event          = ds_event,
1155                 .mtu            = 4096,
1156                 .mode           = LDC_MODE_STREAM,
1157         };
1158         struct mdesc_handle *hp;
1159         struct ldc_channel *lp;
1160         struct ds_info *dp;
1161         const u64 *val;
1162         int err, i;
1163
1164         if (ds_version_printed++ == 0)
1165                 printk(KERN_INFO "%s", version);
1166
1167         dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1168         err = -ENOMEM;
1169         if (!dp)
1170                 goto out_err;
1171
1172         hp = mdesc_grab();
1173         val = mdesc_get_property(hp, vdev->mp, "id", NULL);
1174         if (val)
1175                 dp->id = *val;
1176         mdesc_release(hp);
1177
1178         dp->rcv_buf = kzalloc(4096, GFP_KERNEL);
1179         if (!dp->rcv_buf)
1180                 goto out_free_dp;
1181
1182         dp->rcv_buf_len = 4096;
1183
1184         dp->ds_states = kmemdup(ds_states_template,
1185                                 sizeof(ds_states_template), GFP_KERNEL);
1186         if (!dp->ds_states)
1187                 goto out_free_rcv_buf;
1188
1189         dp->num_ds_states = ARRAY_SIZE(ds_states_template);
1190
1191         for (i = 0; i < dp->num_ds_states; i++)
1192                 dp->ds_states[i].handle = ((u64)i << 32);
1193
1194         ds_cfg.tx_irq = vdev->tx_irq;
1195         ds_cfg.rx_irq = vdev->rx_irq;
1196
1197         lp = ldc_alloc(vdev->channel_id, &ds_cfg, dp);
1198         if (IS_ERR(lp)) {
1199                 err = PTR_ERR(lp);
1200                 goto out_free_ds_states;
1201         }
1202         dp->lp = lp;
1203
1204         err = ldc_bind(lp, "DS");
1205         if (err)
1206                 goto out_free_ldc;
1207
1208         spin_lock_irq(&ds_lock);
1209         dp->next = ds_info_list;
1210         ds_info_list = dp;
1211         spin_unlock_irq(&ds_lock);
1212
1213         return err;
1214
1215 out_free_ldc:
1216         ldc_free(dp->lp);
1217
1218 out_free_ds_states:
1219         kfree(dp->ds_states);
1220
1221 out_free_rcv_buf:
1222         kfree(dp->rcv_buf);
1223
1224 out_free_dp:
1225         kfree(dp);
1226
1227 out_err:
1228         return err;
1229 }
1230
1231 static int ds_remove(struct vio_dev *vdev)
1232 {
1233         return 0;
1234 }
1235
1236 static const struct vio_device_id ds_match[] = {
1237         {
1238                 .type = "domain-services-port",
1239         },
1240         {},
1241 };
1242
1243 static struct vio_driver ds_driver = {
1244         .id_table       = ds_match,
1245         .probe          = ds_probe,
1246         .remove         = ds_remove,
1247         .name           = "ds",
1248 };
1249
1250 static int __init ds_init(void)
1251 {
1252         unsigned long hv_ret, major, minor;
1253
1254         if (tlb_type == hypervisor) {
1255                 hv_ret = sun4v_get_version(HV_GRP_REBOOT_DATA, &major, &minor);
1256                 if (hv_ret == HV_EOK) {
1257                         pr_info("SUN4V: Reboot data supported (maj=%lu,min=%lu).\n",
1258                                 major, minor);
1259                         reboot_data_supported = 1;
1260                 }
1261         }
1262         kthread_run(ds_thread, NULL, "kldomd");
1263
1264         return vio_register_driver(&ds_driver);
1265 }
1266
1267 fs_initcall(ds_init);