V4L/DVB (6049): ivtv: fix VBI reinsertion decoding
[linux-2.6/mini2440.git] / arch / sparc64 / kernel / ldc.c
blob85a2be0b0962201cc9f3237287c6dcb8c9400d85
1 /* ldc.c: Logical Domain Channel link-layer protocol driver.
3 * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
4 */
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/delay.h>
11 #include <linux/errno.h>
12 #include <linux/string.h>
13 #include <linux/scatterlist.h>
14 #include <linux/interrupt.h>
15 #include <linux/list.h>
16 #include <linux/init.h>
18 #include <asm/hypervisor.h>
19 #include <asm/iommu.h>
20 #include <asm/page.h>
21 #include <asm/ldc.h>
22 #include <asm/mdesc.h>
24 #define DRV_MODULE_NAME "ldc"
25 #define PFX DRV_MODULE_NAME ": "
26 #define DRV_MODULE_VERSION "1.0"
27 #define DRV_MODULE_RELDATE "June 25, 2007"
29 static char version[] __devinitdata =
30 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
31 #define LDC_PACKET_SIZE 64
33 /* Packet header layout for unreliable and reliable mode frames.
34 * When in RAW mode, packets are simply straight 64-byte payloads
35 * with no headers.
37 struct ldc_packet {
38 u8 type;
39 #define LDC_CTRL 0x01
40 #define LDC_DATA 0x02
41 #define LDC_ERR 0x10
43 u8 stype;
44 #define LDC_INFO 0x01
45 #define LDC_ACK 0x02
46 #define LDC_NACK 0x04
48 u8 ctrl;
49 #define LDC_VERS 0x01 /* Link Version */
50 #define LDC_RTS 0x02 /* Request To Send */
51 #define LDC_RTR 0x03 /* Ready To Receive */
52 #define LDC_RDX 0x04 /* Ready for Data eXchange */
53 #define LDC_CTRL_MSK 0x0f
55 u8 env;
56 #define LDC_LEN 0x3f
57 #define LDC_FRAG_MASK 0xc0
58 #define LDC_START 0x40
59 #define LDC_STOP 0x80
61 u32 seqid;
63 union {
64 u8 u_data[LDC_PACKET_SIZE - 8];
65 struct {
66 u32 pad;
67 u32 ackid;
68 u8 r_data[LDC_PACKET_SIZE - 8 - 8];
69 } r;
70 } u;
73 struct ldc_version {
74 u16 major;
75 u16 minor;
78 /* Ordered from largest major to lowest. */
79 static struct ldc_version ver_arr[] = {
80 { .major = 1, .minor = 0 },
83 #define LDC_DEFAULT_MTU (4 * LDC_PACKET_SIZE)
84 #define LDC_DEFAULT_NUM_ENTRIES (PAGE_SIZE / LDC_PACKET_SIZE)
86 struct ldc_channel;
88 struct ldc_mode_ops {
89 int (*write)(struct ldc_channel *, const void *, unsigned int);
90 int (*read)(struct ldc_channel *, void *, unsigned int);
93 static const struct ldc_mode_ops raw_ops;
94 static const struct ldc_mode_ops nonraw_ops;
95 static const struct ldc_mode_ops stream_ops;
97 int ldom_domaining_enabled;
99 struct ldc_iommu {
100 /* Protects arena alloc/free. */
101 spinlock_t lock;
102 struct iommu_arena arena;
103 struct ldc_mtable_entry *page_table;
106 struct ldc_channel {
107 /* Protects all operations that depend upon channel state. */
108 spinlock_t lock;
110 unsigned long id;
112 u8 *mssbuf;
113 u32 mssbuf_len;
114 u32 mssbuf_off;
116 struct ldc_packet *tx_base;
117 unsigned long tx_head;
118 unsigned long tx_tail;
119 unsigned long tx_num_entries;
120 unsigned long tx_ra;
122 unsigned long tx_acked;
124 struct ldc_packet *rx_base;
125 unsigned long rx_head;
126 unsigned long rx_tail;
127 unsigned long rx_num_entries;
128 unsigned long rx_ra;
130 u32 rcv_nxt;
131 u32 snd_nxt;
133 unsigned long chan_state;
135 struct ldc_channel_config cfg;
136 void *event_arg;
138 const struct ldc_mode_ops *mops;
140 struct ldc_iommu iommu;
142 struct ldc_version ver;
144 u8 hs_state;
145 #define LDC_HS_CLOSED 0x00
146 #define LDC_HS_OPEN 0x01
147 #define LDC_HS_GOTVERS 0x02
148 #define LDC_HS_SENTRTR 0x03
149 #define LDC_HS_GOTRTR 0x04
150 #define LDC_HS_COMPLETE 0x10
152 u8 flags;
153 #define LDC_FLAG_ALLOCED_QUEUES 0x01
154 #define LDC_FLAG_REGISTERED_QUEUES 0x02
155 #define LDC_FLAG_REGISTERED_IRQS 0x04
156 #define LDC_FLAG_RESET 0x10
158 u8 mss;
159 u8 state;
161 #define LDC_IRQ_NAME_MAX 32
162 char rx_irq_name[LDC_IRQ_NAME_MAX];
163 char tx_irq_name[LDC_IRQ_NAME_MAX];
165 struct hlist_head mh_list;
167 struct hlist_node list;
170 #define ldcdbg(TYPE, f, a...) \
171 do { if (lp->cfg.debug & LDC_DEBUG_##TYPE) \
172 printk(KERN_INFO PFX "ID[%lu] " f, lp->id, ## a); \
173 } while (0)
175 static const char *state_to_str(u8 state)
177 switch (state) {
178 case LDC_STATE_INVALID:
179 return "INVALID";
180 case LDC_STATE_INIT:
181 return "INIT";
182 case LDC_STATE_BOUND:
183 return "BOUND";
184 case LDC_STATE_READY:
185 return "READY";
186 case LDC_STATE_CONNECTED:
187 return "CONNECTED";
188 default:
189 return "<UNKNOWN>";
193 static void ldc_set_state(struct ldc_channel *lp, u8 state)
195 ldcdbg(STATE, "STATE (%s) --> (%s)\n",
196 state_to_str(lp->state),
197 state_to_str(state));
199 lp->state = state;
202 static unsigned long __advance(unsigned long off, unsigned long num_entries)
204 off += LDC_PACKET_SIZE;
205 if (off == (num_entries * LDC_PACKET_SIZE))
206 off = 0;
208 return off;
211 static unsigned long rx_advance(struct ldc_channel *lp, unsigned long off)
213 return __advance(off, lp->rx_num_entries);
216 static unsigned long tx_advance(struct ldc_channel *lp, unsigned long off)
218 return __advance(off, lp->tx_num_entries);
221 static struct ldc_packet *handshake_get_tx_packet(struct ldc_channel *lp,
222 unsigned long *new_tail)
224 struct ldc_packet *p;
225 unsigned long t;
227 t = tx_advance(lp, lp->tx_tail);
228 if (t == lp->tx_head)
229 return NULL;
231 *new_tail = t;
233 p = lp->tx_base;
234 return p + (lp->tx_tail / LDC_PACKET_SIZE);
237 /* When we are in reliable or stream mode, have to track the next packet
238 * we haven't gotten an ACK for in the TX queue using tx_acked. We have
239 * to be careful not to stomp over the queue past that point. During
240 * the handshake, we don't have TX data packets pending in the queue
241 * and that's why handshake_get_tx_packet() need not be mindful of
242 * lp->tx_acked.
244 static unsigned long head_for_data(struct ldc_channel *lp)
246 if (lp->cfg.mode == LDC_MODE_STREAM)
247 return lp->tx_acked;
248 return lp->tx_head;
251 static int tx_has_space_for(struct ldc_channel *lp, unsigned int size)
253 unsigned long limit, tail, new_tail, diff;
254 unsigned int mss;
256 limit = head_for_data(lp);
257 tail = lp->tx_tail;
258 new_tail = tx_advance(lp, tail);
259 if (new_tail == limit)
260 return 0;
262 if (limit > new_tail)
263 diff = limit - new_tail;
264 else
265 diff = (limit +
266 ((lp->tx_num_entries * LDC_PACKET_SIZE) - new_tail));
267 diff /= LDC_PACKET_SIZE;
268 mss = lp->mss;
270 if (diff * mss < size)
271 return 0;
273 return 1;
276 static struct ldc_packet *data_get_tx_packet(struct ldc_channel *lp,
277 unsigned long *new_tail)
279 struct ldc_packet *p;
280 unsigned long h, t;
282 h = head_for_data(lp);
283 t = tx_advance(lp, lp->tx_tail);
284 if (t == h)
285 return NULL;
287 *new_tail = t;
289 p = lp->tx_base;
290 return p + (lp->tx_tail / LDC_PACKET_SIZE);
293 static int set_tx_tail(struct ldc_channel *lp, unsigned long tail)
295 unsigned long orig_tail = lp->tx_tail;
296 int limit = 1000;
298 lp->tx_tail = tail;
299 while (limit-- > 0) {
300 unsigned long err;
302 err = sun4v_ldc_tx_set_qtail(lp->id, tail);
303 if (!err)
304 return 0;
306 if (err != HV_EWOULDBLOCK) {
307 lp->tx_tail = orig_tail;
308 return -EINVAL;
310 udelay(1);
313 lp->tx_tail = orig_tail;
314 return -EBUSY;
317 /* This just updates the head value in the hypervisor using
318 * a polling loop with a timeout. The caller takes care of
319 * upating software state representing the head change, if any.
321 static int __set_rx_head(struct ldc_channel *lp, unsigned long head)
323 int limit = 1000;
325 while (limit-- > 0) {
326 unsigned long err;
328 err = sun4v_ldc_rx_set_qhead(lp->id, head);
329 if (!err)
330 return 0;
332 if (err != HV_EWOULDBLOCK)
333 return -EINVAL;
335 udelay(1);
338 return -EBUSY;
341 static int send_tx_packet(struct ldc_channel *lp,
342 struct ldc_packet *p,
343 unsigned long new_tail)
345 BUG_ON(p != (lp->tx_base + (lp->tx_tail / LDC_PACKET_SIZE)));
347 return set_tx_tail(lp, new_tail);
350 static struct ldc_packet *handshake_compose_ctrl(struct ldc_channel *lp,
351 u8 stype, u8 ctrl,
352 void *data, int dlen,
353 unsigned long *new_tail)
355 struct ldc_packet *p = handshake_get_tx_packet(lp, new_tail);
357 if (p) {
358 memset(p, 0, sizeof(*p));
359 p->type = LDC_CTRL;
360 p->stype = stype;
361 p->ctrl = ctrl;
362 if (data)
363 memcpy(p->u.u_data, data, dlen);
365 return p;
368 static int start_handshake(struct ldc_channel *lp)
370 struct ldc_packet *p;
371 struct ldc_version *ver;
372 unsigned long new_tail;
374 ver = &ver_arr[0];
376 ldcdbg(HS, "SEND VER INFO maj[%u] min[%u]\n",
377 ver->major, ver->minor);
379 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
380 ver, sizeof(*ver), &new_tail);
381 if (p) {
382 int err = send_tx_packet(lp, p, new_tail);
383 if (!err)
384 lp->flags &= ~LDC_FLAG_RESET;
385 return err;
387 return -EBUSY;
390 static int send_version_nack(struct ldc_channel *lp,
391 u16 major, u16 minor)
393 struct ldc_packet *p;
394 struct ldc_version ver;
395 unsigned long new_tail;
397 ver.major = major;
398 ver.minor = minor;
400 p = handshake_compose_ctrl(lp, LDC_NACK, LDC_VERS,
401 &ver, sizeof(ver), &new_tail);
402 if (p) {
403 ldcdbg(HS, "SEND VER NACK maj[%u] min[%u]\n",
404 ver.major, ver.minor);
406 return send_tx_packet(lp, p, new_tail);
408 return -EBUSY;
411 static int send_version_ack(struct ldc_channel *lp,
412 struct ldc_version *vp)
414 struct ldc_packet *p;
415 unsigned long new_tail;
417 p = handshake_compose_ctrl(lp, LDC_ACK, LDC_VERS,
418 vp, sizeof(*vp), &new_tail);
419 if (p) {
420 ldcdbg(HS, "SEND VER ACK maj[%u] min[%u]\n",
421 vp->major, vp->minor);
423 return send_tx_packet(lp, p, new_tail);
425 return -EBUSY;
428 static int send_rts(struct ldc_channel *lp)
430 struct ldc_packet *p;
431 unsigned long new_tail;
433 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTS, NULL, 0,
434 &new_tail);
435 if (p) {
436 p->env = lp->cfg.mode;
437 p->seqid = 0;
438 lp->rcv_nxt = 0;
440 ldcdbg(HS, "SEND RTS env[0x%x] seqid[0x%x]\n",
441 p->env, p->seqid);
443 return send_tx_packet(lp, p, new_tail);
445 return -EBUSY;
448 static int send_rtr(struct ldc_channel *lp)
450 struct ldc_packet *p;
451 unsigned long new_tail;
453 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RTR, NULL, 0,
454 &new_tail);
455 if (p) {
456 p->env = lp->cfg.mode;
457 p->seqid = 0;
459 ldcdbg(HS, "SEND RTR env[0x%x] seqid[0x%x]\n",
460 p->env, p->seqid);
462 return send_tx_packet(lp, p, new_tail);
464 return -EBUSY;
467 static int send_rdx(struct ldc_channel *lp)
469 struct ldc_packet *p;
470 unsigned long new_tail;
472 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_RDX, NULL, 0,
473 &new_tail);
474 if (p) {
475 p->env = 0;
476 p->seqid = ++lp->snd_nxt;
477 p->u.r.ackid = lp->rcv_nxt;
479 ldcdbg(HS, "SEND RDX env[0x%x] seqid[0x%x] ackid[0x%x]\n",
480 p->env, p->seqid, p->u.r.ackid);
482 return send_tx_packet(lp, p, new_tail);
484 return -EBUSY;
487 static int send_data_nack(struct ldc_channel *lp, struct ldc_packet *data_pkt)
489 struct ldc_packet *p;
490 unsigned long new_tail;
491 int err;
493 p = data_get_tx_packet(lp, &new_tail);
494 if (!p)
495 return -EBUSY;
496 memset(p, 0, sizeof(*p));
497 p->type = data_pkt->type;
498 p->stype = LDC_NACK;
499 p->ctrl = data_pkt->ctrl & LDC_CTRL_MSK;
500 p->seqid = lp->snd_nxt + 1;
501 p->u.r.ackid = lp->rcv_nxt;
503 ldcdbg(HS, "SEND DATA NACK type[0x%x] ctl[0x%x] seq[0x%x] ack[0x%x]\n",
504 p->type, p->ctrl, p->seqid, p->u.r.ackid);
506 err = send_tx_packet(lp, p, new_tail);
507 if (!err)
508 lp->snd_nxt++;
510 return err;
513 static int ldc_abort(struct ldc_channel *lp)
515 unsigned long hv_err;
517 ldcdbg(STATE, "ABORT\n");
519 /* We report but do not act upon the hypervisor errors because
520 * there really isn't much we can do if they fail at this point.
522 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
523 if (hv_err)
524 printk(KERN_ERR PFX "ldc_abort: "
525 "sun4v_ldc_tx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
526 lp->id, lp->tx_ra, lp->tx_num_entries, hv_err);
528 hv_err = sun4v_ldc_tx_get_state(lp->id,
529 &lp->tx_head,
530 &lp->tx_tail,
531 &lp->chan_state);
532 if (hv_err)
533 printk(KERN_ERR PFX "ldc_abort: "
534 "sun4v_ldc_tx_get_state(%lx,...) failed, err=%lu\n",
535 lp->id, hv_err);
537 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
538 if (hv_err)
539 printk(KERN_ERR PFX "ldc_abort: "
540 "sun4v_ldc_rx_qconf(%lx,%lx,%lx) failed, err=%lu\n",
541 lp->id, lp->rx_ra, lp->rx_num_entries, hv_err);
543 /* Refetch the RX queue state as well, because we could be invoked
544 * here in the queue processing context.
546 hv_err = sun4v_ldc_rx_get_state(lp->id,
547 &lp->rx_head,
548 &lp->rx_tail,
549 &lp->chan_state);
550 if (hv_err)
551 printk(KERN_ERR PFX "ldc_abort: "
552 "sun4v_ldc_rx_get_state(%lx,...) failed, err=%lu\n",
553 lp->id, hv_err);
555 return -ECONNRESET;
558 static struct ldc_version *find_by_major(u16 major)
560 struct ldc_version *ret = NULL;
561 int i;
563 for (i = 0; i < ARRAY_SIZE(ver_arr); i++) {
564 struct ldc_version *v = &ver_arr[i];
565 if (v->major <= major) {
566 ret = v;
567 break;
570 return ret;
573 static int process_ver_info(struct ldc_channel *lp, struct ldc_version *vp)
575 struct ldc_version *vap;
576 int err;
578 ldcdbg(HS, "GOT VERSION INFO major[%x] minor[%x]\n",
579 vp->major, vp->minor);
581 if (lp->hs_state == LDC_HS_GOTVERS) {
582 lp->hs_state = LDC_HS_OPEN;
583 memset(&lp->ver, 0, sizeof(lp->ver));
586 vap = find_by_major(vp->major);
587 if (!vap) {
588 err = send_version_nack(lp, 0, 0);
589 } else if (vap->major != vp->major) {
590 err = send_version_nack(lp, vap->major, vap->minor);
591 } else {
592 struct ldc_version ver = *vp;
593 if (ver.minor > vap->minor)
594 ver.minor = vap->minor;
595 err = send_version_ack(lp, &ver);
596 if (!err) {
597 lp->ver = ver;
598 lp->hs_state = LDC_HS_GOTVERS;
601 if (err)
602 return ldc_abort(lp);
604 return 0;
607 static int process_ver_ack(struct ldc_channel *lp, struct ldc_version *vp)
609 ldcdbg(HS, "GOT VERSION ACK major[%x] minor[%x]\n",
610 vp->major, vp->minor);
612 if (lp->hs_state == LDC_HS_GOTVERS) {
613 if (lp->ver.major != vp->major ||
614 lp->ver.minor != vp->minor)
615 return ldc_abort(lp);
616 } else {
617 lp->ver = *vp;
618 lp->hs_state = LDC_HS_GOTVERS;
620 if (send_rts(lp))
621 return ldc_abort(lp);
622 return 0;
625 static int process_ver_nack(struct ldc_channel *lp, struct ldc_version *vp)
627 struct ldc_version *vap;
629 if ((vp->major == 0 && vp->minor == 0) ||
630 !(vap = find_by_major(vp->major))) {
631 return ldc_abort(lp);
632 } else {
633 struct ldc_packet *p;
634 unsigned long new_tail;
636 p = handshake_compose_ctrl(lp, LDC_INFO, LDC_VERS,
637 vap, sizeof(*vap),
638 &new_tail);
639 if (p)
640 return send_tx_packet(lp, p, new_tail);
641 else
642 return ldc_abort(lp);
646 static int process_version(struct ldc_channel *lp,
647 struct ldc_packet *p)
649 struct ldc_version *vp;
651 vp = (struct ldc_version *) p->u.u_data;
653 switch (p->stype) {
654 case LDC_INFO:
655 return process_ver_info(lp, vp);
657 case LDC_ACK:
658 return process_ver_ack(lp, vp);
660 case LDC_NACK:
661 return process_ver_nack(lp, vp);
663 default:
664 return ldc_abort(lp);
668 static int process_rts(struct ldc_channel *lp,
669 struct ldc_packet *p)
671 ldcdbg(HS, "GOT RTS stype[%x] seqid[%x] env[%x]\n",
672 p->stype, p->seqid, p->env);
674 if (p->stype != LDC_INFO ||
675 lp->hs_state != LDC_HS_GOTVERS ||
676 p->env != lp->cfg.mode)
677 return ldc_abort(lp);
679 lp->snd_nxt = p->seqid;
680 lp->rcv_nxt = p->seqid;
681 lp->hs_state = LDC_HS_SENTRTR;
682 if (send_rtr(lp))
683 return ldc_abort(lp);
685 return 0;
688 static int process_rtr(struct ldc_channel *lp,
689 struct ldc_packet *p)
691 ldcdbg(HS, "GOT RTR stype[%x] seqid[%x] env[%x]\n",
692 p->stype, p->seqid, p->env);
694 if (p->stype != LDC_INFO ||
695 p->env != lp->cfg.mode)
696 return ldc_abort(lp);
698 lp->snd_nxt = p->seqid;
699 lp->hs_state = LDC_HS_COMPLETE;
700 ldc_set_state(lp, LDC_STATE_CONNECTED);
701 send_rdx(lp);
703 return LDC_EVENT_UP;
706 static int rx_seq_ok(struct ldc_channel *lp, u32 seqid)
708 return lp->rcv_nxt + 1 == seqid;
711 static int process_rdx(struct ldc_channel *lp,
712 struct ldc_packet *p)
714 ldcdbg(HS, "GOT RDX stype[%x] seqid[%x] env[%x] ackid[%x]\n",
715 p->stype, p->seqid, p->env, p->u.r.ackid);
717 if (p->stype != LDC_INFO ||
718 !(rx_seq_ok(lp, p->seqid)))
719 return ldc_abort(lp);
721 lp->rcv_nxt = p->seqid;
723 lp->hs_state = LDC_HS_COMPLETE;
724 ldc_set_state(lp, LDC_STATE_CONNECTED);
726 return LDC_EVENT_UP;
729 static int process_control_frame(struct ldc_channel *lp,
730 struct ldc_packet *p)
732 switch (p->ctrl) {
733 case LDC_VERS:
734 return process_version(lp, p);
736 case LDC_RTS:
737 return process_rts(lp, p);
739 case LDC_RTR:
740 return process_rtr(lp, p);
742 case LDC_RDX:
743 return process_rdx(lp, p);
745 default:
746 return ldc_abort(lp);
750 static int process_error_frame(struct ldc_channel *lp,
751 struct ldc_packet *p)
753 return ldc_abort(lp);
756 static int process_data_ack(struct ldc_channel *lp,
757 struct ldc_packet *ack)
759 unsigned long head = lp->tx_acked;
760 u32 ackid = ack->u.r.ackid;
762 while (1) {
763 struct ldc_packet *p = lp->tx_base + (head / LDC_PACKET_SIZE);
765 head = tx_advance(lp, head);
767 if (p->seqid == ackid) {
768 lp->tx_acked = head;
769 return 0;
771 if (head == lp->tx_tail)
772 return ldc_abort(lp);
775 return 0;
778 static void send_events(struct ldc_channel *lp, unsigned int event_mask)
780 if (event_mask & LDC_EVENT_RESET)
781 lp->cfg.event(lp->event_arg, LDC_EVENT_RESET);
782 if (event_mask & LDC_EVENT_UP)
783 lp->cfg.event(lp->event_arg, LDC_EVENT_UP);
784 if (event_mask & LDC_EVENT_DATA_READY)
785 lp->cfg.event(lp->event_arg, LDC_EVENT_DATA_READY);
788 static irqreturn_t ldc_rx(int irq, void *dev_id)
790 struct ldc_channel *lp = dev_id;
791 unsigned long orig_state, hv_err, flags;
792 unsigned int event_mask;
794 spin_lock_irqsave(&lp->lock, flags);
796 orig_state = lp->chan_state;
797 hv_err = sun4v_ldc_rx_get_state(lp->id,
798 &lp->rx_head,
799 &lp->rx_tail,
800 &lp->chan_state);
802 ldcdbg(RX, "RX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
803 orig_state, lp->chan_state, lp->rx_head, lp->rx_tail);
805 event_mask = 0;
807 if (lp->cfg.mode == LDC_MODE_RAW &&
808 lp->chan_state == LDC_CHANNEL_UP) {
809 lp->hs_state = LDC_HS_COMPLETE;
810 ldc_set_state(lp, LDC_STATE_CONNECTED);
812 event_mask |= LDC_EVENT_UP;
814 orig_state = lp->chan_state;
817 /* If we are in reset state, flush the RX queue and ignore
818 * everything.
820 if (lp->flags & LDC_FLAG_RESET) {
821 (void) __set_rx_head(lp, lp->rx_tail);
822 goto out;
825 /* Once we finish the handshake, we let the ldc_read()
826 * paths do all of the control frame and state management.
827 * Just trigger the callback.
829 if (lp->hs_state == LDC_HS_COMPLETE) {
830 handshake_complete:
831 if (lp->chan_state != orig_state) {
832 unsigned int event = LDC_EVENT_RESET;
834 if (lp->chan_state == LDC_CHANNEL_UP)
835 event = LDC_EVENT_UP;
837 event_mask |= event;
839 if (lp->rx_head != lp->rx_tail)
840 event_mask |= LDC_EVENT_DATA_READY;
842 goto out;
845 if (lp->chan_state != orig_state)
846 goto out;
848 while (lp->rx_head != lp->rx_tail) {
849 struct ldc_packet *p;
850 unsigned long new;
851 int err;
853 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
855 switch (p->type) {
856 case LDC_CTRL:
857 err = process_control_frame(lp, p);
858 if (err > 0)
859 event_mask |= err;
860 break;
862 case LDC_DATA:
863 event_mask |= LDC_EVENT_DATA_READY;
864 err = 0;
865 break;
867 case LDC_ERR:
868 err = process_error_frame(lp, p);
869 break;
871 default:
872 err = ldc_abort(lp);
873 break;
876 if (err < 0)
877 break;
879 new = lp->rx_head;
880 new += LDC_PACKET_SIZE;
881 if (new == (lp->rx_num_entries * LDC_PACKET_SIZE))
882 new = 0;
883 lp->rx_head = new;
885 err = __set_rx_head(lp, new);
886 if (err < 0) {
887 (void) ldc_abort(lp);
888 break;
890 if (lp->hs_state == LDC_HS_COMPLETE)
891 goto handshake_complete;
894 out:
895 spin_unlock_irqrestore(&lp->lock, flags);
897 send_events(lp, event_mask);
899 return IRQ_HANDLED;
902 static irqreturn_t ldc_tx(int irq, void *dev_id)
904 struct ldc_channel *lp = dev_id;
905 unsigned long flags, hv_err, orig_state;
906 unsigned int event_mask = 0;
908 spin_lock_irqsave(&lp->lock, flags);
910 orig_state = lp->chan_state;
911 hv_err = sun4v_ldc_tx_get_state(lp->id,
912 &lp->tx_head,
913 &lp->tx_tail,
914 &lp->chan_state);
916 ldcdbg(TX, " TX state[0x%02lx:0x%02lx] head[0x%04lx] tail[0x%04lx]\n",
917 orig_state, lp->chan_state, lp->tx_head, lp->tx_tail);
919 if (lp->cfg.mode == LDC_MODE_RAW &&
920 lp->chan_state == LDC_CHANNEL_UP) {
921 lp->hs_state = LDC_HS_COMPLETE;
922 ldc_set_state(lp, LDC_STATE_CONNECTED);
924 event_mask |= LDC_EVENT_UP;
927 spin_unlock_irqrestore(&lp->lock, flags);
929 send_events(lp, event_mask);
931 return IRQ_HANDLED;
934 /* XXX ldc_alloc() and ldc_free() needs to run under a mutex so
935 * XXX that addition and removal from the ldc_channel_list has
936 * XXX atomicity, otherwise the __ldc_channel_exists() check is
937 * XXX totally pointless as another thread can slip into ldc_alloc()
938 * XXX and add a channel with the same ID. There also needs to be
939 * XXX a spinlock for ldc_channel_list.
941 static HLIST_HEAD(ldc_channel_list);
943 static int __ldc_channel_exists(unsigned long id)
945 struct ldc_channel *lp;
946 struct hlist_node *n;
948 hlist_for_each_entry(lp, n, &ldc_channel_list, list) {
949 if (lp->id == id)
950 return 1;
952 return 0;
955 static int alloc_queue(const char *name, unsigned long num_entries,
956 struct ldc_packet **base, unsigned long *ra)
958 unsigned long size, order;
959 void *q;
961 size = num_entries * LDC_PACKET_SIZE;
962 order = get_order(size);
964 q = (void *) __get_free_pages(GFP_KERNEL, order);
965 if (!q) {
966 printk(KERN_ERR PFX "Alloc of %s queue failed with "
967 "size=%lu order=%lu\n", name, size, order);
968 return -ENOMEM;
971 memset(q, 0, PAGE_SIZE << order);
973 *base = q;
974 *ra = __pa(q);
976 return 0;
979 static void free_queue(unsigned long num_entries, struct ldc_packet *q)
981 unsigned long size, order;
983 if (!q)
984 return;
986 size = num_entries * LDC_PACKET_SIZE;
987 order = get_order(size);
989 free_pages((unsigned long)q, order);
992 /* XXX Make this configurable... XXX */
993 #define LDC_IOTABLE_SIZE (8 * 1024)
995 static int ldc_iommu_init(struct ldc_channel *lp)
997 unsigned long sz, num_tsb_entries, tsbsize, order;
998 struct ldc_iommu *iommu = &lp->iommu;
999 struct ldc_mtable_entry *table;
1000 unsigned long hv_err;
1001 int err;
1003 num_tsb_entries = LDC_IOTABLE_SIZE;
1004 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1006 spin_lock_init(&iommu->lock);
1008 sz = num_tsb_entries / 8;
1009 sz = (sz + 7UL) & ~7UL;
1010 iommu->arena.map = kzalloc(sz, GFP_KERNEL);
1011 if (!iommu->arena.map) {
1012 printk(KERN_ERR PFX "Alloc of arena map failed, sz=%lu\n", sz);
1013 return -ENOMEM;
1016 iommu->arena.limit = num_tsb_entries;
1018 order = get_order(tsbsize);
1020 table = (struct ldc_mtable_entry *)
1021 __get_free_pages(GFP_KERNEL, order);
1022 err = -ENOMEM;
1023 if (!table) {
1024 printk(KERN_ERR PFX "Alloc of MTE table failed, "
1025 "size=%lu order=%lu\n", tsbsize, order);
1026 goto out_free_map;
1029 memset(table, 0, PAGE_SIZE << order);
1031 iommu->page_table = table;
1033 hv_err = sun4v_ldc_set_map_table(lp->id, __pa(table),
1034 num_tsb_entries);
1035 err = -EINVAL;
1036 if (hv_err)
1037 goto out_free_table;
1039 return 0;
1041 out_free_table:
1042 free_pages((unsigned long) table, order);
1043 iommu->page_table = NULL;
1045 out_free_map:
1046 kfree(iommu->arena.map);
1047 iommu->arena.map = NULL;
1049 return err;
1052 static void ldc_iommu_release(struct ldc_channel *lp)
1054 struct ldc_iommu *iommu = &lp->iommu;
1055 unsigned long num_tsb_entries, tsbsize, order;
1057 (void) sun4v_ldc_set_map_table(lp->id, 0, 0);
1059 num_tsb_entries = iommu->arena.limit;
1060 tsbsize = num_tsb_entries * sizeof(struct ldc_mtable_entry);
1061 order = get_order(tsbsize);
1063 free_pages((unsigned long) iommu->page_table, order);
1064 iommu->page_table = NULL;
1066 kfree(iommu->arena.map);
1067 iommu->arena.map = NULL;
1070 struct ldc_channel *ldc_alloc(unsigned long id,
1071 const struct ldc_channel_config *cfgp,
1072 void *event_arg)
1074 struct ldc_channel *lp;
1075 const struct ldc_mode_ops *mops;
1076 unsigned long dummy1, dummy2, hv_err;
1077 u8 mss, *mssbuf;
1078 int err;
1080 err = -ENODEV;
1081 if (!ldom_domaining_enabled)
1082 goto out_err;
1084 err = -EINVAL;
1085 if (!cfgp)
1086 goto out_err;
1088 switch (cfgp->mode) {
1089 case LDC_MODE_RAW:
1090 mops = &raw_ops;
1091 mss = LDC_PACKET_SIZE;
1092 break;
1094 case LDC_MODE_UNRELIABLE:
1095 mops = &nonraw_ops;
1096 mss = LDC_PACKET_SIZE - 8;
1097 break;
1099 case LDC_MODE_STREAM:
1100 mops = &stream_ops;
1101 mss = LDC_PACKET_SIZE - 8 - 8;
1102 break;
1104 default:
1105 goto out_err;
1108 if (!cfgp->event || !event_arg || !cfgp->rx_irq || !cfgp->tx_irq)
1109 goto out_err;
1111 hv_err = sun4v_ldc_tx_qinfo(id, &dummy1, &dummy2);
1112 err = -ENODEV;
1113 if (hv_err == HV_ECHANNEL)
1114 goto out_err;
1116 err = -EEXIST;
1117 if (__ldc_channel_exists(id))
1118 goto out_err;
1120 mssbuf = NULL;
1122 lp = kzalloc(sizeof(*lp), GFP_KERNEL);
1123 err = -ENOMEM;
1124 if (!lp)
1125 goto out_err;
1127 spin_lock_init(&lp->lock);
1129 lp->id = id;
1131 err = ldc_iommu_init(lp);
1132 if (err)
1133 goto out_free_ldc;
1135 lp->mops = mops;
1136 lp->mss = mss;
1138 lp->cfg = *cfgp;
1139 if (!lp->cfg.mtu)
1140 lp->cfg.mtu = LDC_DEFAULT_MTU;
1142 if (lp->cfg.mode == LDC_MODE_STREAM) {
1143 mssbuf = kzalloc(lp->cfg.mtu, GFP_KERNEL);
1144 if (!mssbuf) {
1145 err = -ENOMEM;
1146 goto out_free_iommu;
1148 lp->mssbuf = mssbuf;
1151 lp->event_arg = event_arg;
1153 /* XXX allow setting via ldc_channel_config to override defaults
1154 * XXX or use some formula based upon mtu
1156 lp->tx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1157 lp->rx_num_entries = LDC_DEFAULT_NUM_ENTRIES;
1159 err = alloc_queue("TX", lp->tx_num_entries,
1160 &lp->tx_base, &lp->tx_ra);
1161 if (err)
1162 goto out_free_mssbuf;
1164 err = alloc_queue("RX", lp->rx_num_entries,
1165 &lp->rx_base, &lp->rx_ra);
1166 if (err)
1167 goto out_free_txq;
1169 lp->flags |= LDC_FLAG_ALLOCED_QUEUES;
1171 lp->hs_state = LDC_HS_CLOSED;
1172 ldc_set_state(lp, LDC_STATE_INIT);
1174 INIT_HLIST_NODE(&lp->list);
1175 hlist_add_head(&lp->list, &ldc_channel_list);
1177 INIT_HLIST_HEAD(&lp->mh_list);
1179 return lp;
1181 out_free_txq:
1182 free_queue(lp->tx_num_entries, lp->tx_base);
1184 out_free_mssbuf:
1185 if (mssbuf)
1186 kfree(mssbuf);
1188 out_free_iommu:
1189 ldc_iommu_release(lp);
1191 out_free_ldc:
1192 kfree(lp);
1194 out_err:
1195 return ERR_PTR(err);
1197 EXPORT_SYMBOL(ldc_alloc);
1199 void ldc_free(struct ldc_channel *lp)
1201 if (lp->flags & LDC_FLAG_REGISTERED_IRQS) {
1202 free_irq(lp->cfg.rx_irq, lp);
1203 free_irq(lp->cfg.tx_irq, lp);
1206 if (lp->flags & LDC_FLAG_REGISTERED_QUEUES) {
1207 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1208 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1209 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1211 if (lp->flags & LDC_FLAG_ALLOCED_QUEUES) {
1212 free_queue(lp->tx_num_entries, lp->tx_base);
1213 free_queue(lp->rx_num_entries, lp->rx_base);
1214 lp->flags &= ~LDC_FLAG_ALLOCED_QUEUES;
1217 hlist_del(&lp->list);
1219 if (lp->mssbuf)
1220 kfree(lp->mssbuf);
1222 ldc_iommu_release(lp);
1224 kfree(lp);
1226 EXPORT_SYMBOL(ldc_free);
1228 /* Bind the channel. This registers the LDC queues with
1229 * the hypervisor and puts the channel into a pseudo-listening
1230 * state. This does not initiate a handshake, ldc_connect() does
1231 * that.
1233 int ldc_bind(struct ldc_channel *lp, const char *name)
1235 unsigned long hv_err, flags;
1236 int err = -EINVAL;
1238 spin_lock_irqsave(&lp->lock, flags);
1240 if (!name)
1241 goto out_err;
1243 if (lp->state != LDC_STATE_INIT)
1244 goto out_err;
1246 snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
1247 snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
1249 err = request_irq(lp->cfg.rx_irq, ldc_rx,
1250 IRQF_SAMPLE_RANDOM | IRQF_SHARED,
1251 lp->rx_irq_name, lp);
1252 if (err)
1253 goto out_err;
1255 err = request_irq(lp->cfg.tx_irq, ldc_tx,
1256 IRQF_SAMPLE_RANDOM | IRQF_SHARED,
1257 lp->tx_irq_name, lp);
1258 if (err)
1259 goto out_free_rx_irq;
1262 lp->flags |= LDC_FLAG_REGISTERED_IRQS;
1264 err = -ENODEV;
1265 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1266 if (hv_err)
1267 goto out_free_tx_irq;
1269 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1270 if (hv_err)
1271 goto out_free_tx_irq;
1273 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1274 if (hv_err)
1275 goto out_unmap_tx;
1277 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1278 if (hv_err)
1279 goto out_unmap_tx;
1281 lp->flags |= LDC_FLAG_REGISTERED_QUEUES;
1283 hv_err = sun4v_ldc_tx_get_state(lp->id,
1284 &lp->tx_head,
1285 &lp->tx_tail,
1286 &lp->chan_state);
1287 err = -EBUSY;
1288 if (hv_err)
1289 goto out_unmap_rx;
1291 lp->tx_acked = lp->tx_head;
1293 lp->hs_state = LDC_HS_OPEN;
1294 ldc_set_state(lp, LDC_STATE_BOUND);
1296 spin_unlock_irqrestore(&lp->lock, flags);
1298 return 0;
1300 out_unmap_rx:
1301 lp->flags &= ~LDC_FLAG_REGISTERED_QUEUES;
1302 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1304 out_unmap_tx:
1305 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1307 out_free_tx_irq:
1308 lp->flags &= ~LDC_FLAG_REGISTERED_IRQS;
1309 free_irq(lp->cfg.tx_irq, lp);
1311 out_free_rx_irq:
1312 free_irq(lp->cfg.rx_irq, lp);
1314 out_err:
1315 spin_unlock_irqrestore(&lp->lock, flags);
1317 return err;
1319 EXPORT_SYMBOL(ldc_bind);
1321 int ldc_connect(struct ldc_channel *lp)
1323 unsigned long flags;
1324 int err;
1326 if (lp->cfg.mode == LDC_MODE_RAW)
1327 return -EINVAL;
1329 spin_lock_irqsave(&lp->lock, flags);
1331 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1332 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES) ||
1333 lp->hs_state != LDC_HS_OPEN)
1334 err = -EINVAL;
1335 else
1336 err = start_handshake(lp);
1338 spin_unlock_irqrestore(&lp->lock, flags);
1340 return err;
1342 EXPORT_SYMBOL(ldc_connect);
1344 int ldc_disconnect(struct ldc_channel *lp)
1346 unsigned long hv_err, flags;
1347 int err;
1349 if (lp->cfg.mode == LDC_MODE_RAW)
1350 return -EINVAL;
1352 if (!(lp->flags & LDC_FLAG_ALLOCED_QUEUES) ||
1353 !(lp->flags & LDC_FLAG_REGISTERED_QUEUES))
1354 return -EINVAL;
1356 spin_lock_irqsave(&lp->lock, flags);
1358 err = -ENODEV;
1359 hv_err = sun4v_ldc_tx_qconf(lp->id, 0, 0);
1360 if (hv_err)
1361 goto out_err;
1363 hv_err = sun4v_ldc_tx_qconf(lp->id, lp->tx_ra, lp->tx_num_entries);
1364 if (hv_err)
1365 goto out_err;
1367 hv_err = sun4v_ldc_rx_qconf(lp->id, 0, 0);
1368 if (hv_err)
1369 goto out_err;
1371 hv_err = sun4v_ldc_rx_qconf(lp->id, lp->rx_ra, lp->rx_num_entries);
1372 if (hv_err)
1373 goto out_err;
1375 ldc_set_state(lp, LDC_STATE_BOUND);
1376 lp->hs_state = LDC_HS_OPEN;
1377 lp->flags |= LDC_FLAG_RESET;
1379 spin_unlock_irqrestore(&lp->lock, flags);
1381 return 0;
1383 out_err:
1384 sun4v_ldc_tx_qconf(lp->id, 0, 0);
1385 sun4v_ldc_rx_qconf(lp->id, 0, 0);
1386 free_irq(lp->cfg.tx_irq, lp);
1387 free_irq(lp->cfg.rx_irq, lp);
1388 lp->flags &= ~(LDC_FLAG_REGISTERED_IRQS |
1389 LDC_FLAG_REGISTERED_QUEUES);
1390 ldc_set_state(lp, LDC_STATE_INIT);
1392 spin_unlock_irqrestore(&lp->lock, flags);
1394 return err;
1396 EXPORT_SYMBOL(ldc_disconnect);
1398 int ldc_state(struct ldc_channel *lp)
1400 return lp->state;
1402 EXPORT_SYMBOL(ldc_state);
1404 static int write_raw(struct ldc_channel *lp, const void *buf, unsigned int size)
1406 struct ldc_packet *p;
1407 unsigned long new_tail;
1408 int err;
1410 if (size > LDC_PACKET_SIZE)
1411 return -EMSGSIZE;
1413 p = data_get_tx_packet(lp, &new_tail);
1414 if (!p)
1415 return -EAGAIN;
1417 memcpy(p, buf, size);
1419 err = send_tx_packet(lp, p, new_tail);
1420 if (!err)
1421 err = size;
1423 return err;
1426 static int read_raw(struct ldc_channel *lp, void *buf, unsigned int size)
1428 struct ldc_packet *p;
1429 unsigned long hv_err, new;
1430 int err;
1432 if (size < LDC_PACKET_SIZE)
1433 return -EINVAL;
1435 hv_err = sun4v_ldc_rx_get_state(lp->id,
1436 &lp->rx_head,
1437 &lp->rx_tail,
1438 &lp->chan_state);
1439 if (hv_err)
1440 return ldc_abort(lp);
1442 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1443 lp->chan_state == LDC_CHANNEL_RESETTING)
1444 return -ECONNRESET;
1446 if (lp->rx_head == lp->rx_tail)
1447 return 0;
1449 p = lp->rx_base + (lp->rx_head / LDC_PACKET_SIZE);
1450 memcpy(buf, p, LDC_PACKET_SIZE);
1452 new = rx_advance(lp, lp->rx_head);
1453 lp->rx_head = new;
1455 err = __set_rx_head(lp, new);
1456 if (err < 0)
1457 err = -ECONNRESET;
1458 else
1459 err = LDC_PACKET_SIZE;
1461 return err;
1464 static const struct ldc_mode_ops raw_ops = {
1465 .write = write_raw,
1466 .read = read_raw,
1469 static int write_nonraw(struct ldc_channel *lp, const void *buf,
1470 unsigned int size)
1472 unsigned long hv_err, tail;
1473 unsigned int copied;
1474 u32 seq;
1475 int err;
1477 hv_err = sun4v_ldc_tx_get_state(lp->id, &lp->tx_head, &lp->tx_tail,
1478 &lp->chan_state);
1479 if (unlikely(hv_err))
1480 return -EBUSY;
1482 if (unlikely(lp->chan_state != LDC_CHANNEL_UP))
1483 return ldc_abort(lp);
1485 if (!tx_has_space_for(lp, size))
1486 return -EAGAIN;
1488 seq = lp->snd_nxt;
1489 copied = 0;
1490 tail = lp->tx_tail;
1491 while (copied < size) {
1492 struct ldc_packet *p = lp->tx_base + (tail / LDC_PACKET_SIZE);
1493 u8 *data = ((lp->cfg.mode == LDC_MODE_UNRELIABLE) ?
1494 p->u.u_data :
1495 p->u.r.r_data);
1496 int data_len;
1498 p->type = LDC_DATA;
1499 p->stype = LDC_INFO;
1500 p->ctrl = 0;
1502 data_len = size - copied;
1503 if (data_len > lp->mss)
1504 data_len = lp->mss;
1506 BUG_ON(data_len > LDC_LEN);
1508 p->env = (data_len |
1509 (copied == 0 ? LDC_START : 0) |
1510 (data_len == size - copied ? LDC_STOP : 0));
1512 p->seqid = ++seq;
1514 ldcdbg(DATA, "SENT DATA [%02x:%02x:%02x:%02x:%08x]\n",
1515 p->type,
1516 p->stype,
1517 p->ctrl,
1518 p->env,
1519 p->seqid);
1521 memcpy(data, buf, data_len);
1522 buf += data_len;
1523 copied += data_len;
1525 tail = tx_advance(lp, tail);
1528 err = set_tx_tail(lp, tail);
1529 if (!err) {
1530 lp->snd_nxt = seq;
1531 err = size;
1534 return err;
1537 static int rx_bad_seq(struct ldc_channel *lp, struct ldc_packet *p,
1538 struct ldc_packet *first_frag)
1540 int err;
1542 if (first_frag)
1543 lp->rcv_nxt = first_frag->seqid - 1;
1545 err = send_data_nack(lp, p);
1546 if (err)
1547 return err;
1549 err = __set_rx_head(lp, lp->rx_tail);
1550 if (err < 0)
1551 return ldc_abort(lp);
1553 return 0;
1556 static int data_ack_nack(struct ldc_channel *lp, struct ldc_packet *p)
1558 if (p->stype & LDC_ACK) {
1559 int err = process_data_ack(lp, p);
1560 if (err)
1561 return err;
1563 if (p->stype & LDC_NACK)
1564 return ldc_abort(lp);
1566 return 0;
1569 static int rx_data_wait(struct ldc_channel *lp, unsigned long cur_head)
1571 unsigned long dummy;
1572 int limit = 1000;
1574 ldcdbg(DATA, "DATA WAIT cur_head[%lx] rx_head[%lx] rx_tail[%lx]\n",
1575 cur_head, lp->rx_head, lp->rx_tail);
1576 while (limit-- > 0) {
1577 unsigned long hv_err;
1579 hv_err = sun4v_ldc_rx_get_state(lp->id,
1580 &dummy,
1581 &lp->rx_tail,
1582 &lp->chan_state);
1583 if (hv_err)
1584 return ldc_abort(lp);
1586 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1587 lp->chan_state == LDC_CHANNEL_RESETTING)
1588 return -ECONNRESET;
1590 if (cur_head != lp->rx_tail) {
1591 ldcdbg(DATA, "DATA WAIT DONE "
1592 "head[%lx] tail[%lx] chan_state[%lx]\n",
1593 dummy, lp->rx_tail, lp->chan_state);
1594 return 0;
1597 udelay(1);
1599 return -EAGAIN;
1602 static int rx_set_head(struct ldc_channel *lp, unsigned long head)
1604 int err = __set_rx_head(lp, head);
1606 if (err < 0)
1607 return ldc_abort(lp);
1609 lp->rx_head = head;
1610 return 0;
1613 static void send_data_ack(struct ldc_channel *lp)
1615 unsigned long new_tail;
1616 struct ldc_packet *p;
1618 p = data_get_tx_packet(lp, &new_tail);
1619 if (likely(p)) {
1620 int err;
1622 memset(p, 0, sizeof(*p));
1623 p->type = LDC_DATA;
1624 p->stype = LDC_ACK;
1625 p->ctrl = 0;
1626 p->seqid = lp->snd_nxt + 1;
1627 p->u.r.ackid = lp->rcv_nxt;
1629 err = send_tx_packet(lp, p, new_tail);
1630 if (!err)
1631 lp->snd_nxt++;
1635 static int read_nonraw(struct ldc_channel *lp, void *buf, unsigned int size)
1637 struct ldc_packet *first_frag;
1638 unsigned long hv_err, new;
1639 int err, copied;
1641 hv_err = sun4v_ldc_rx_get_state(lp->id,
1642 &lp->rx_head,
1643 &lp->rx_tail,
1644 &lp->chan_state);
1645 if (hv_err)
1646 return ldc_abort(lp);
1648 if (lp->chan_state == LDC_CHANNEL_DOWN ||
1649 lp->chan_state == LDC_CHANNEL_RESETTING)
1650 return -ECONNRESET;
1652 if (lp->rx_head == lp->rx_tail)
1653 return 0;
1655 first_frag = NULL;
1656 copied = err = 0;
1657 new = lp->rx_head;
1658 while (1) {
1659 struct ldc_packet *p;
1660 int pkt_len;
1662 BUG_ON(new == lp->rx_tail);
1663 p = lp->rx_base + (new / LDC_PACKET_SIZE);
1665 ldcdbg(RX, "RX read pkt[%02x:%02x:%02x:%02x:%08x:%08x] "
1666 "rcv_nxt[%08x]\n",
1667 p->type,
1668 p->stype,
1669 p->ctrl,
1670 p->env,
1671 p->seqid,
1672 p->u.r.ackid,
1673 lp->rcv_nxt);
1675 if (unlikely(!rx_seq_ok(lp, p->seqid))) {
1676 err = rx_bad_seq(lp, p, first_frag);
1677 copied = 0;
1678 break;
1681 if (p->type & LDC_CTRL) {
1682 err = process_control_frame(lp, p);
1683 if (err < 0)
1684 break;
1685 err = 0;
1688 lp->rcv_nxt = p->seqid;
1690 if (!(p->type & LDC_DATA)) {
1691 new = rx_advance(lp, new);
1692 goto no_data;
1694 if (p->stype & (LDC_ACK | LDC_NACK)) {
1695 err = data_ack_nack(lp, p);
1696 if (err)
1697 break;
1699 if (!(p->stype & LDC_INFO)) {
1700 new = rx_advance(lp, new);
1701 err = rx_set_head(lp, new);
1702 if (err)
1703 break;
1704 goto no_data;
1707 pkt_len = p->env & LDC_LEN;
1709 /* Every initial packet starts with the START bit set.
1711 * Singleton packets will have both START+STOP set.
1713 * Fragments will have START set in the first frame, STOP
1714 * set in the last frame, and neither bit set in middle
1715 * frames of the packet.
1717 * Therefore if we are at the beginning of a packet and
1718 * we don't see START, or we are in the middle of a fragmented
1719 * packet and do see START, we are unsynchronized and should
1720 * flush the RX queue.
1722 if ((first_frag == NULL && !(p->env & LDC_START)) ||
1723 (first_frag != NULL && (p->env & LDC_START))) {
1724 if (!first_frag)
1725 new = rx_advance(lp, new);
1727 err = rx_set_head(lp, new);
1728 if (err)
1729 break;
1731 if (!first_frag)
1732 goto no_data;
1734 if (!first_frag)
1735 first_frag = p;
1737 if (pkt_len > size - copied) {
1738 /* User didn't give us a big enough buffer,
1739 * what to do? This is a pretty serious error.
1741 * Since we haven't updated the RX ring head to
1742 * consume any of the packets, signal the error
1743 * to the user and just leave the RX ring alone.
1745 * This seems the best behavior because this allows
1746 * a user of the LDC layer to start with a small
1747 * RX buffer for ldc_read() calls and use -EMSGSIZE
1748 * as a cue to enlarge it's read buffer.
1750 err = -EMSGSIZE;
1751 break;
1754 /* Ok, we are gonna eat this one. */
1755 new = rx_advance(lp, new);
1757 memcpy(buf,
1758 (lp->cfg.mode == LDC_MODE_UNRELIABLE ?
1759 p->u.u_data : p->u.r.r_data), pkt_len);
1760 buf += pkt_len;
1761 copied += pkt_len;
1763 if (p->env & LDC_STOP)
1764 break;
1766 no_data:
1767 if (new == lp->rx_tail) {
1768 err = rx_data_wait(lp, new);
1769 if (err)
1770 break;
1774 if (!err)
1775 err = rx_set_head(lp, new);
1777 if (err && first_frag)
1778 lp->rcv_nxt = first_frag->seqid - 1;
1780 if (!err) {
1781 err = copied;
1782 if (err > 0 && lp->cfg.mode != LDC_MODE_UNRELIABLE)
1783 send_data_ack(lp);
1786 return err;
1789 static const struct ldc_mode_ops nonraw_ops = {
1790 .write = write_nonraw,
1791 .read = read_nonraw,
1794 static int write_stream(struct ldc_channel *lp, const void *buf,
1795 unsigned int size)
1797 if (size > lp->cfg.mtu)
1798 size = lp->cfg.mtu;
1799 return write_nonraw(lp, buf, size);
1802 static int read_stream(struct ldc_channel *lp, void *buf, unsigned int size)
1804 if (!lp->mssbuf_len) {
1805 int err = read_nonraw(lp, lp->mssbuf, lp->cfg.mtu);
1806 if (err < 0)
1807 return err;
1809 lp->mssbuf_len = err;
1810 lp->mssbuf_off = 0;
1813 if (size > lp->mssbuf_len)
1814 size = lp->mssbuf_len;
1815 memcpy(buf, lp->mssbuf + lp->mssbuf_off, size);
1817 lp->mssbuf_off += size;
1818 lp->mssbuf_len -= size;
1820 return size;
1823 static const struct ldc_mode_ops stream_ops = {
1824 .write = write_stream,
1825 .read = read_stream,
1828 int ldc_write(struct ldc_channel *lp, const void *buf, unsigned int size)
1830 unsigned long flags;
1831 int err;
1833 if (!buf)
1834 return -EINVAL;
1836 if (!size)
1837 return 0;
1839 spin_lock_irqsave(&lp->lock, flags);
1841 if (lp->hs_state != LDC_HS_COMPLETE)
1842 err = -ENOTCONN;
1843 else
1844 err = lp->mops->write(lp, buf, size);
1846 spin_unlock_irqrestore(&lp->lock, flags);
1848 return err;
1850 EXPORT_SYMBOL(ldc_write);
1852 int ldc_read(struct ldc_channel *lp, void *buf, unsigned int size)
1854 unsigned long flags;
1855 int err;
1857 if (!buf)
1858 return -EINVAL;
1860 if (!size)
1861 return 0;
1863 spin_lock_irqsave(&lp->lock, flags);
1865 if (lp->hs_state != LDC_HS_COMPLETE)
1866 err = -ENOTCONN;
1867 else
1868 err = lp->mops->read(lp, buf, size);
1870 spin_unlock_irqrestore(&lp->lock, flags);
1872 return err;
1874 EXPORT_SYMBOL(ldc_read);
1876 static long arena_alloc(struct ldc_iommu *iommu, unsigned long npages)
1878 struct iommu_arena *arena = &iommu->arena;
1879 unsigned long n, i, start, end, limit;
1880 int pass;
1882 limit = arena->limit;
1883 start = arena->hint;
1884 pass = 0;
1886 again:
1887 n = find_next_zero_bit(arena->map, limit, start);
1888 end = n + npages;
1889 if (unlikely(end >= limit)) {
1890 if (likely(pass < 1)) {
1891 limit = start;
1892 start = 0;
1893 pass++;
1894 goto again;
1895 } else {
1896 /* Scanned the whole thing, give up. */
1897 return -1;
1901 for (i = n; i < end; i++) {
1902 if (test_bit(i, arena->map)) {
1903 start = i + 1;
1904 goto again;
1908 for (i = n; i < end; i++)
1909 __set_bit(i, arena->map);
1911 arena->hint = end;
1913 return n;
1916 #define COOKIE_PGSZ_CODE 0xf000000000000000ULL
1917 #define COOKIE_PGSZ_CODE_SHIFT 60ULL
1919 static u64 pagesize_code(void)
1921 switch (PAGE_SIZE) {
1922 default:
1923 case (8ULL * 1024ULL):
1924 return 0;
1925 case (64ULL * 1024ULL):
1926 return 1;
1927 case (512ULL * 1024ULL):
1928 return 2;
1929 case (4ULL * 1024ULL * 1024ULL):
1930 return 3;
1931 case (32ULL * 1024ULL * 1024ULL):
1932 return 4;
1933 case (256ULL * 1024ULL * 1024ULL):
1934 return 5;
1938 static u64 make_cookie(u64 index, u64 pgsz_code, u64 page_offset)
1940 return ((pgsz_code << COOKIE_PGSZ_CODE_SHIFT) |
1941 (index << PAGE_SHIFT) |
1942 page_offset);
1945 static u64 cookie_to_index(u64 cookie, unsigned long *shift)
1947 u64 szcode = cookie >> COOKIE_PGSZ_CODE_SHIFT;
1949 cookie &= ~COOKIE_PGSZ_CODE;
1951 *shift = szcode * 3;
1953 return (cookie >> (13ULL + (szcode * 3ULL)));
1956 static struct ldc_mtable_entry *alloc_npages(struct ldc_iommu *iommu,
1957 unsigned long npages)
1959 long entry;
1961 entry = arena_alloc(iommu, npages);
1962 if (unlikely(entry < 0))
1963 return NULL;
1965 return iommu->page_table + entry;
1968 static u64 perm_to_mte(unsigned int map_perm)
1970 u64 mte_base;
1972 mte_base = pagesize_code();
1974 if (map_perm & LDC_MAP_SHADOW) {
1975 if (map_perm & LDC_MAP_R)
1976 mte_base |= LDC_MTE_COPY_R;
1977 if (map_perm & LDC_MAP_W)
1978 mte_base |= LDC_MTE_COPY_W;
1980 if (map_perm & LDC_MAP_DIRECT) {
1981 if (map_perm & LDC_MAP_R)
1982 mte_base |= LDC_MTE_READ;
1983 if (map_perm & LDC_MAP_W)
1984 mte_base |= LDC_MTE_WRITE;
1985 if (map_perm & LDC_MAP_X)
1986 mte_base |= LDC_MTE_EXEC;
1988 if (map_perm & LDC_MAP_IO) {
1989 if (map_perm & LDC_MAP_R)
1990 mte_base |= LDC_MTE_IOMMU_R;
1991 if (map_perm & LDC_MAP_W)
1992 mte_base |= LDC_MTE_IOMMU_W;
1995 return mte_base;
1998 static int pages_in_region(unsigned long base, long len)
2000 int count = 0;
2002 do {
2003 unsigned long new = (base + PAGE_SIZE) & PAGE_MASK;
2005 len -= (new - base);
2006 base = new;
2007 count++;
2008 } while (len > 0);
2010 return count;
2013 struct cookie_state {
2014 struct ldc_mtable_entry *page_table;
2015 struct ldc_trans_cookie *cookies;
2016 u64 mte_base;
2017 u64 prev_cookie;
2018 u32 pte_idx;
2019 u32 nc;
2022 static void fill_cookies(struct cookie_state *sp, unsigned long pa,
2023 unsigned long off, unsigned long len)
2025 do {
2026 unsigned long tlen, new = pa + PAGE_SIZE;
2027 u64 this_cookie;
2029 sp->page_table[sp->pte_idx].mte = sp->mte_base | pa;
2031 tlen = PAGE_SIZE;
2032 if (off)
2033 tlen = PAGE_SIZE - off;
2034 if (tlen > len)
2035 tlen = len;
2037 this_cookie = make_cookie(sp->pte_idx,
2038 pagesize_code(), off);
2040 off = 0;
2042 if (this_cookie == sp->prev_cookie) {
2043 sp->cookies[sp->nc - 1].cookie_size += tlen;
2044 } else {
2045 sp->cookies[sp->nc].cookie_addr = this_cookie;
2046 sp->cookies[sp->nc].cookie_size = tlen;
2047 sp->nc++;
2049 sp->prev_cookie = this_cookie + tlen;
2051 sp->pte_idx++;
2053 len -= tlen;
2054 pa = new;
2055 } while (len > 0);
2058 static int sg_count_one(struct scatterlist *sg)
2060 unsigned long base = page_to_pfn(sg->page) << PAGE_SHIFT;
2061 long len = sg->length;
2063 if ((sg->offset | len) & (8UL - 1))
2064 return -EFAULT;
2066 return pages_in_region(base + sg->offset, len);
2069 static int sg_count_pages(struct scatterlist *sg, int num_sg)
2071 int count;
2072 int i;
2074 count = 0;
2075 for (i = 0; i < num_sg; i++) {
2076 int err = sg_count_one(sg + i);
2077 if (err < 0)
2078 return err;
2079 count += err;
2082 return count;
2085 int ldc_map_sg(struct ldc_channel *lp,
2086 struct scatterlist *sg, int num_sg,
2087 struct ldc_trans_cookie *cookies, int ncookies,
2088 unsigned int map_perm)
2090 unsigned long i, npages, flags;
2091 struct ldc_mtable_entry *base;
2092 struct cookie_state state;
2093 struct ldc_iommu *iommu;
2094 int err;
2096 if (map_perm & ~LDC_MAP_ALL)
2097 return -EINVAL;
2099 err = sg_count_pages(sg, num_sg);
2100 if (err < 0)
2101 return err;
2103 npages = err;
2104 if (err > ncookies)
2105 return -EMSGSIZE;
2107 iommu = &lp->iommu;
2109 spin_lock_irqsave(&iommu->lock, flags);
2110 base = alloc_npages(iommu, npages);
2111 spin_unlock_irqrestore(&iommu->lock, flags);
2113 if (!base)
2114 return -ENOMEM;
2116 state.page_table = iommu->page_table;
2117 state.cookies = cookies;
2118 state.mte_base = perm_to_mte(map_perm);
2119 state.prev_cookie = ~(u64)0;
2120 state.pte_idx = (base - iommu->page_table);
2121 state.nc = 0;
2123 for (i = 0; i < num_sg; i++)
2124 fill_cookies(&state, page_to_pfn(sg[i].page) << PAGE_SHIFT,
2125 sg[i].offset, sg[i].length);
2127 return state.nc;
2129 EXPORT_SYMBOL(ldc_map_sg);
2131 int ldc_map_single(struct ldc_channel *lp,
2132 void *buf, unsigned int len,
2133 struct ldc_trans_cookie *cookies, int ncookies,
2134 unsigned int map_perm)
2136 unsigned long npages, pa, flags;
2137 struct ldc_mtable_entry *base;
2138 struct cookie_state state;
2139 struct ldc_iommu *iommu;
2141 if ((map_perm & ~LDC_MAP_ALL) || (ncookies < 1))
2142 return -EINVAL;
2144 pa = __pa(buf);
2145 if ((pa | len) & (8UL - 1))
2146 return -EFAULT;
2148 npages = pages_in_region(pa, len);
2150 iommu = &lp->iommu;
2152 spin_lock_irqsave(&iommu->lock, flags);
2153 base = alloc_npages(iommu, npages);
2154 spin_unlock_irqrestore(&iommu->lock, flags);
2156 if (!base)
2157 return -ENOMEM;
2159 state.page_table = iommu->page_table;
2160 state.cookies = cookies;
2161 state.mte_base = perm_to_mte(map_perm);
2162 state.prev_cookie = ~(u64)0;
2163 state.pte_idx = (base - iommu->page_table);
2164 state.nc = 0;
2165 fill_cookies(&state, (pa & PAGE_MASK), (pa & ~PAGE_MASK), len);
2166 BUG_ON(state.nc != 1);
2168 return state.nc;
2170 EXPORT_SYMBOL(ldc_map_single);
2172 static void free_npages(unsigned long id, struct ldc_iommu *iommu,
2173 u64 cookie, u64 size)
2175 struct iommu_arena *arena = &iommu->arena;
2176 unsigned long i, shift, index, npages;
2177 struct ldc_mtable_entry *base;
2179 npages = PAGE_ALIGN(((cookie & ~PAGE_MASK) + size)) >> PAGE_SHIFT;
2180 index = cookie_to_index(cookie, &shift);
2181 base = iommu->page_table + index;
2183 BUG_ON(index > arena->limit ||
2184 (index + npages) > arena->limit);
2186 for (i = 0; i < npages; i++) {
2187 if (base->cookie)
2188 sun4v_ldc_revoke(id, cookie + (i << shift),
2189 base->cookie);
2190 base->mte = 0;
2191 __clear_bit(index + i, arena->map);
2195 void ldc_unmap(struct ldc_channel *lp, struct ldc_trans_cookie *cookies,
2196 int ncookies)
2198 struct ldc_iommu *iommu = &lp->iommu;
2199 unsigned long flags;
2200 int i;
2202 spin_lock_irqsave(&iommu->lock, flags);
2203 for (i = 0; i < ncookies; i++) {
2204 u64 addr = cookies[i].cookie_addr;
2205 u64 size = cookies[i].cookie_size;
2207 free_npages(lp->id, iommu, addr, size);
2209 spin_unlock_irqrestore(&iommu->lock, flags);
2211 EXPORT_SYMBOL(ldc_unmap);
2213 int ldc_copy(struct ldc_channel *lp, int copy_dir,
2214 void *buf, unsigned int len, unsigned long offset,
2215 struct ldc_trans_cookie *cookies, int ncookies)
2217 unsigned int orig_len;
2218 unsigned long ra;
2219 int i;
2221 if (copy_dir != LDC_COPY_IN && copy_dir != LDC_COPY_OUT) {
2222 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Bad copy_dir[%d]\n",
2223 lp->id, copy_dir);
2224 return -EINVAL;
2227 ra = __pa(buf);
2228 if ((ra | len | offset) & (8UL - 1)) {
2229 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Unaligned buffer "
2230 "ra[%lx] len[%x] offset[%lx]\n",
2231 lp->id, ra, len, offset);
2232 return -EFAULT;
2235 if (lp->hs_state != LDC_HS_COMPLETE ||
2236 (lp->flags & LDC_FLAG_RESET)) {
2237 printk(KERN_ERR PFX "ldc_copy: ID[%lu] Link down hs_state[%x] "
2238 "flags[%x]\n", lp->id, lp->hs_state, lp->flags);
2239 return -ECONNRESET;
2242 orig_len = len;
2243 for (i = 0; i < ncookies; i++) {
2244 unsigned long cookie_raddr = cookies[i].cookie_addr;
2245 unsigned long this_len = cookies[i].cookie_size;
2246 unsigned long actual_len;
2248 if (unlikely(offset)) {
2249 unsigned long this_off = offset;
2251 if (this_off > this_len)
2252 this_off = this_len;
2254 offset -= this_off;
2255 this_len -= this_off;
2256 if (!this_len)
2257 continue;
2258 cookie_raddr += this_off;
2261 if (this_len > len)
2262 this_len = len;
2264 while (1) {
2265 unsigned long hv_err;
2267 hv_err = sun4v_ldc_copy(lp->id, copy_dir,
2268 cookie_raddr, ra,
2269 this_len, &actual_len);
2270 if (unlikely(hv_err)) {
2271 printk(KERN_ERR PFX "ldc_copy: ID[%lu] "
2272 "HV error %lu\n",
2273 lp->id, hv_err);
2274 if (lp->hs_state != LDC_HS_COMPLETE ||
2275 (lp->flags & LDC_FLAG_RESET))
2276 return -ECONNRESET;
2277 else
2278 return -EFAULT;
2281 cookie_raddr += actual_len;
2282 ra += actual_len;
2283 len -= actual_len;
2284 if (actual_len == this_len)
2285 break;
2287 this_len -= actual_len;
2290 if (!len)
2291 break;
2294 /* It is caller policy what to do about short copies.
2295 * For example, a networking driver can declare the
2296 * packet a runt and drop it.
2299 return orig_len - len;
2301 EXPORT_SYMBOL(ldc_copy);
2303 void *ldc_alloc_exp_dring(struct ldc_channel *lp, unsigned int len,
2304 struct ldc_trans_cookie *cookies, int *ncookies,
2305 unsigned int map_perm)
2307 void *buf;
2308 int err;
2310 if (len & (8UL - 1))
2311 return ERR_PTR(-EINVAL);
2313 buf = kzalloc(len, GFP_KERNEL);
2314 if (!buf)
2315 return ERR_PTR(-ENOMEM);
2317 err = ldc_map_single(lp, buf, len, cookies, *ncookies, map_perm);
2318 if (err < 0) {
2319 kfree(buf);
2320 return ERR_PTR(err);
2322 *ncookies = err;
2324 return buf;
2326 EXPORT_SYMBOL(ldc_alloc_exp_dring);
2328 void ldc_free_exp_dring(struct ldc_channel *lp, void *buf, unsigned int len,
2329 struct ldc_trans_cookie *cookies, int ncookies)
2331 ldc_unmap(lp, cookies, ncookies);
2332 kfree(buf);
2334 EXPORT_SYMBOL(ldc_free_exp_dring);
2336 static int __init ldc_init(void)
2338 unsigned long major, minor;
2339 struct mdesc_handle *hp;
2340 const u64 *v;
2341 u64 mp;
2343 hp = mdesc_grab();
2344 if (!hp)
2345 return -ENODEV;
2347 mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
2348 if (mp == MDESC_NODE_NULL)
2349 return -ENODEV;
2351 v = mdesc_get_property(hp, mp, "domaining-enabled", NULL);
2352 if (!v)
2353 return -ENODEV;
2355 major = 1;
2356 minor = 0;
2357 if (sun4v_hvapi_register(HV_GRP_LDOM, major, &minor)) {
2358 printk(KERN_INFO PFX "Could not register LDOM hvapi.\n");
2359 return -ENODEV;
2362 printk(KERN_INFO "%s", version);
2364 if (!*v) {
2365 printk(KERN_INFO PFX "Domaining disabled.\n");
2366 return -ENODEV;
2368 ldom_domaining_enabled = 1;
2370 return 0;
2373 core_initcall(ldc_init);