aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/ieee1394/csr.c
blob: ab0c80f61b9d184152d6ed2005cfae5f360e7835 (plain) (tree)
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847


















                                                                         

                          



                              
                         





                           
                          























































































































                                                                                            
                                                               
  

                                                                       


                                                            


                                                               
 
                                                                          


























































                                                                                            
                                                                                













































































































































































































































































































































































































































































































































































































































                                                                                                          
/*
 * IEEE 1394 for Linux
 *
 * CSR implementation, iso/bus manager implementation.
 *
 * Copyright (C) 1999 Andreas E. Bombe
 *               2002 Manfred Weihs <weihs@ict.tuwien.ac.at>
 *
 * This code is licensed under the GPL.  See the file COPYING in the root
 * directory of the kernel sources for details.
 *
 *
 * Contributions:
 *
 * Manfred Weihs <weihs@ict.tuwien.ac.at>
 *        configuration ROM manipulation
 *
 */

#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/param.h>
#include <linux/spinlock.h>
#include <linux/string.h>

#include "csr1212.h"
#include "ieee1394_types.h"
#include "hosts.h"
#include "ieee1394.h"
#include "highlevel.h"
#include "ieee1394_core.h"

/* Module Parameters */
/* this module parameter can be used to disable mapping of the FCP registers */

static int fcp = 1;
module_param(fcp, int, 0444);
MODULE_PARM_DESC(fcp, "Map FCP registers (default = 1, disable = 0).");

static struct csr1212_keyval *node_cap = NULL;

static void add_host(struct hpsb_host *host);
static void remove_host(struct hpsb_host *host);
static void host_reset(struct hpsb_host *host);
static int read_maps(struct hpsb_host *host, int nodeid, quadlet_t *buffer,
		     u64 addr, size_t length, u16 fl);
static int write_fcp(struct hpsb_host *host, int nodeid, int dest,
		     quadlet_t *data, u64 addr, size_t length, u16 flags);
static int read_regs(struct hpsb_host *host, int nodeid, quadlet_t *buf,
		     u64 addr, size_t length, u16 flags);
static int write_regs(struct hpsb_host *host, int nodeid, int destid,
		      quadlet_t *data, u64 addr, size_t length, u16 flags);
static int lock_regs(struct hpsb_host *host, int nodeid, quadlet_t *store,
		     u64 addr, quadlet_t data, quadlet_t arg, int extcode, u16 fl);
static int lock64_regs(struct hpsb_host *host, int nodeid, octlet_t * store,
		       u64 addr, octlet_t data, octlet_t arg, int extcode, u16 fl);
static int read_config_rom(struct hpsb_host *host, int nodeid, quadlet_t *buffer,
			   u64 addr, size_t length, u16 fl);
static u64 allocate_addr_range(u64 size, u32 alignment, void *__host);
static void release_addr_range(u64 addr, void *__host);

static struct hpsb_highlevel csr_highlevel = {
	.name =		"standard registers",
	.add_host =	add_host,
	.remove_host =	remove_host,
	.host_reset =	host_reset,
};

static struct hpsb_address_ops map_ops = {
	.read = read_maps,
};

static struct hpsb_address_ops fcp_ops = {
	.write = write_fcp,
};

static struct hpsb_address_ops reg_ops = {
	.read = read_regs,
	.write = write_regs,
	.lock = lock_regs,
	.lock64 = lock64_regs,
};

static struct hpsb_address_ops config_rom_ops = {
	.read = read_config_rom,
};

struct csr1212_bus_ops csr_bus_ops = {
	.allocate_addr_range =	allocate_addr_range,
	.release_addr =		release_addr_range,
};


static u16 csr_crc16(unsigned *data, int length)
{
        int check=0, i;
        int shift, sum, next=0;

        for (i = length; i; i--) {
                for (next = check, shift = 28; shift >= 0; shift -= 4 ) {
                        sum = ((next >> 12) ^ (be32_to_cpu(*data) >> shift)) & 0xf;
                        next = (next << 4) ^ (sum << 12) ^ (sum << 5) ^ (sum);
                }
                check = next & 0xffff;
                data++;
        }

        return check;
}

static void host_reset(struct hpsb_host *host)
{
        host->csr.state &= 0x300;

        host->csr.bus_manager_id = 0x3f;
        host->csr.bandwidth_available = 4915;
	host->csr.channels_available_hi = 0xfffffffe;	/* pre-alloc ch 31 per 1394a-2000 */
        host->csr.channels_available_lo = ~0;
	host->csr.broadcast_channel = 0x80000000 | 31;

	if (host->is_irm) {
		if (host->driver->hw_csr_reg) {
			host->driver->hw_csr_reg(host, 2, 0xfffffffe, ~0);
		}
	}

        host->csr.node_ids = host->node_id << 16;

        if (!host->is_root) {
                /* clear cmstr bit */
                host->csr.state &= ~0x100;
        }

        host->csr.topology_map[1] =
                cpu_to_be32(be32_to_cpu(host->csr.topology_map[1]) + 1);
        host->csr.topology_map[2] = cpu_to_be32(host->node_count << 16
                                                | host->selfid_count);
        host->csr.topology_map[0] =
                cpu_to_be32((host->selfid_count + 2) << 16
                            | csr_crc16(host->csr.topology_map + 1,
                                        host->selfid_count + 2));

        host->csr.speed_map[1] =
                cpu_to_be32(be32_to_cpu(host->csr.speed_map[1]) + 1);
        host->csr.speed_map[0] = cpu_to_be32(0x3f1 << 16
                                             | csr_crc16(host->csr.speed_map+1,
                                                         0x3f1));
}

/*
 * HI == seconds (bits 0:2)
 * LO == fractions of a second in units of 125usec (bits 19:31)
 *
 * Convert SPLIT_TIMEOUT to jiffies.
 * The default and minimum as per 1394a-2000 clause 8.3.2.2.6 is 100ms.
 */
static inline void calculate_expire(struct csr_control *csr)
{
	unsigned long usecs =
		(csr->split_timeout_hi & 0x07) * USEC_PER_SEC +
		(csr->split_timeout_lo >> 19) * 125L;

	csr->expire = usecs_to_jiffies(usecs > 100000L ? usecs : 100000L);

	HPSB_VERBOSE("CSR: setting expire to %lu, HZ=%u", csr->expire, HZ);
}


static void add_host(struct hpsb_host *host)
{
	struct csr1212_keyval *root;
	quadlet_t bus_info[CSR_BUS_INFO_SIZE];

	hpsb_register_addrspace(&csr_highlevel, host, &reg_ops,
				CSR_REGISTER_BASE,
				CSR_REGISTER_BASE + CSR_CONFIG_ROM);
	hpsb_register_addrspace(&csr_highlevel, host, &config_rom_ops,
				CSR_REGISTER_BASE + CSR_CONFIG_ROM,
				CSR_REGISTER_BASE + CSR_CONFIG_ROM_END);
	if (fcp) {
		hpsb_register_addrspace(&csr_highlevel, host, &fcp_ops,
					CSR_REGISTER_BASE + CSR_FCP_COMMAND,
					CSR_REGISTER_BASE + CSR_FCP_END);
	}
	hpsb_register_addrspace(&csr_highlevel, host, &map_ops,
				CSR_REGISTER_BASE + CSR_TOPOLOGY_MAP,
				CSR_REGISTER_BASE + CSR_TOPOLOGY_MAP_END);
	hpsb_register_addrspace(&csr_highlevel, host, &map_ops,
				CSR_REGISTER_BASE + CSR_SPEED_MAP,
				CSR_REGISTER_BASE + CSR_SPEED_MAP_END);

        spin_lock_init(&host->csr.lock);

        host->csr.state                 = 0;
        host->csr.node_ids              = 0;
        host->csr.split_timeout_hi      = 0;
        host->csr.split_timeout_lo      = 800 << 19;
	calculate_expire(&host->csr);
        host->csr.cycle_time            = 0;
        host->csr.bus_time              = 0;
        host->csr.bus_manager_id        = 0x3f;
        host->csr.bandwidth_available   = 4915;
	host->csr.channels_available_hi = 0xfffffffe;	/* pre-alloc ch 31 per 1394a-2000 */
        host->csr.channels_available_lo = ~0;
	host->csr.broadcast_channel = 0x80000000 | 31;

	if (host->is_irm) {
		if (host->driver->hw_csr_reg) {
			host->driver->hw_csr_reg(host, 2, 0xfffffffe, ~0);
		}
	}

	if (host->csr.max_rec >= 9)
		host->csr.max_rom = 2;
	else if (host->csr.max_rec >= 5)
		host->csr.max_rom = 1;
	else
		host->csr.max_rom = 0;

	host->csr.generation = 2;

	bus_info[1] = __constant_cpu_to_be32(0x31333934);
	bus_info[2] = cpu_to_be32((hpsb_disable_irm ? 0 : 1 << CSR_IRMC_SHIFT) |
				  (1 << CSR_CMC_SHIFT) |
				  (1 << CSR_ISC_SHIFT) |
				  (0 << CSR_BMC_SHIFT) |
				  (0 << CSR_PMC_SHIFT) |
				  (host->csr.cyc_clk_acc << CSR_CYC_CLK_ACC_SHIFT) |
				  (host->csr.max_rec << CSR_MAX_REC_SHIFT) |
				  (host->csr.max_rom << CSR_MAX_ROM_SHIFT) |
				  (host->csr.generation << CSR_GENERATION_SHIFT) |
				  host->csr.lnk_spd);

	bus_info[3] = cpu_to_be32(host->csr.guid_hi);
	bus_info[4] = cpu_to_be32(host->csr.guid_lo);

	/* The hardware copy of the bus info block will be set later when a
	 * bus reset is issued. */

	csr1212_init_local_csr(host->csr.rom, bus_info, host->csr.max_rom);

	root = host->csr.rom->root_kv;

	if(csr1212_attach_keyval_to_directory(root, node_cap) != CSR1212_SUCCESS) {
		HPSB_ERR("Failed to attach Node Capabilities to root directory");
	}

	host->update_config_rom = 1;
}

static void remove_host(struct hpsb_host *host)
{
	quadlet_t bus_info[CSR_BUS_INFO_SIZE];

	bus_info[1] = __constant_cpu_to_be32(0x31333934);
	bus_info[2] = cpu_to_be32((0 << CSR_IRMC_SHIFT) |
				  (0 << CSR_CMC_SHIFT) |
				  (0 << CSR_ISC_SHIFT) |
				  (0 << CSR_BMC_SHIFT) |
				  (0 << CSR_PMC_SHIFT) |
				  (host->csr.cyc_clk_acc << CSR_CYC_CLK_ACC_SHIFT) |
				  (host->csr.max_rec << CSR_MAX_REC_SHIFT) |
				  (0 << CSR_MAX_ROM_SHIFT) |
				  (0 << CSR_GENERATION_SHIFT) |
				  host->csr.lnk_spd);

	bus_info[3] = cpu_to_be32(host->csr.guid_hi);
	bus_info[4] = cpu_to_be32(host->csr.guid_lo);

	csr1212_detach_keyval_from_directory(host->csr.rom->root_kv, node_cap);

	csr1212_init_local_csr(host->csr.rom, bus_info, 0);
	host->update_config_rom = 1;
}


int hpsb_update_config_rom(struct hpsb_host *host, const quadlet_t *new_rom,
	size_t buffersize, unsigned char rom_version)
{
	unsigned long flags;
	int ret;

	HPSB_NOTICE("hpsb_update_config_rom() is deprecated");

        spin_lock_irqsave(&host->csr.lock, flags);
	if (rom_version != host->csr.generation)
                ret = -1;
	else if (buffersize > host->csr.rom->cache_head->size)
		ret = -2;
        else {
		/* Just overwrite the generated ConfigROM image with new data,
		 * it can be regenerated later. */
		memcpy(host->csr.rom->cache_head->data, new_rom, buffersize);
		host->csr.rom->cache_head->len = buffersize;

		if (host->driver->set_hw_config_rom)
			host->driver->set_hw_config_rom(host, host->csr.rom->bus_info_data);
		/* Increment the generation number to keep some sort of sync
		 * with the newer ConfigROM manipulation method. */
		host->csr.generation++;
		if (host->csr.generation > 0xf || host->csr.generation < 2)
			host->csr.generation = 2;
		ret=0;
        }
        spin_unlock_irqrestore(&host->csr.lock, flags);
        return ret;
}


/* Read topology / speed maps and configuration ROM */
static int read_maps(struct hpsb_host *host, int nodeid, quadlet_t *buffer,
                     u64 addr, size_t length, u16 fl)
{
	unsigned long flags;
        int csraddr = addr - CSR_REGISTER_BASE;
        const char *src;

        spin_lock_irqsave(&host->csr.lock, flags);

	if (csraddr < CSR_SPEED_MAP) {
                src = ((char *)host->csr.topology_map) + csraddr
                        - CSR_TOPOLOGY_MAP;
        } else {
                src = ((char *)host->csr.speed_map) + csraddr - CSR_SPEED_MAP;
        }

        memcpy(buffer, src, length);
        spin_unlock_irqrestore(&host->csr.lock, flags);
        return RCODE_COMPLETE;
}


#define out if (--length == 0) break

static int read_regs(struct hpsb_host *host, int nodeid, quadlet_t *buf,
                     u64 addr, size_t length, u16 flags)
{
        int csraddr = addr - CSR_REGISTER_BASE;
        int oldcycle;
        quadlet_t ret;

        if ((csraddr | length) & 0x3)
                return RCODE_TYPE_ERROR;

        length /= 4;

        switch (csraddr) {
        case CSR_STATE_CLEAR:
                *(buf++) = cpu_to_be32(host->csr.state);
                out;
        case CSR_STATE_SET:
                *(buf++) = cpu_to_be32(host->csr.state);
                out;
        case CSR_NODE_IDS:
                *(buf++) = cpu_to_be32(host->csr.node_ids);
                out;

        case CSR_RESET_START:
                return RCODE_TYPE_ERROR;

                /* address gap - handled by default below */

        case CSR_SPLIT_TIMEOUT_HI:
                *(buf++) = cpu_to_be32(host->csr.split_timeout_hi);
                out;
        case CSR_SPLIT_TIMEOUT_LO:
                *(buf++) = cpu_to_be32(host->csr.split_timeout_lo);
                out;

                /* address gap */
                return RCODE_ADDRESS_ERROR;

        case CSR_CYCLE_TIME:
                oldcycle = host->csr.cycle_time;
                host->csr.cycle_time =
                        host->driver->devctl(host, GET_CYCLE_COUNTER, 0);

                if (oldcycle > host->csr.cycle_time) {
                        /* cycle time wrapped around */
                        host->csr.bus_time += 1 << 7;
                }
                *(buf++) = cpu_to_be32(host->csr.cycle_time);
                out;
        case CSR_BUS_TIME:
                oldcycle = host->csr.cycle_time;
                host->csr.cycle_time =
                        host->driver->devctl(host, GET_CYCLE_COUNTER, 0);

                if (oldcycle > host->csr.cycle_time) {
                        /* cycle time wrapped around */
                        host->csr.bus_time += (1 << 7);
                }
                *(buf++) = cpu_to_be32(host->csr.bus_time
                                       | (host->csr.cycle_time >> 25));
                out;

                /* address gap */
                return RCODE_ADDRESS_ERROR;

        case CSR_BUSY_TIMEOUT:
                /* not yet implemented */
                return RCODE_ADDRESS_ERROR;

        case CSR_BUS_MANAGER_ID:
                if (host->driver->hw_csr_reg)
                        ret = host->driver->hw_csr_reg(host, 0, 0, 0);
                else
                        ret = host->csr.bus_manager_id;

                *(buf++) = cpu_to_be32(ret);
                out;
        case CSR_BANDWIDTH_AVAILABLE:
                if (host->driver->hw_csr_reg)
                        ret = host->driver->hw_csr_reg(host, 1, 0, 0);
                else
                        ret = host->csr.bandwidth_available;

                *(buf++) = cpu_to_be32(ret);
                out;
        case CSR_CHANNELS_AVAILABLE_HI:
                if (host->driver->hw_csr_reg)
                        ret = host->driver->hw_csr_reg(host, 2, 0, 0);
                else
                        ret = host->csr.channels_available_hi;

                *(buf++) = cpu_to_be32(ret);
                out;
        case CSR_CHANNELS_AVAILABLE_LO:
                if (host->driver->hw_csr_reg)
                        ret = host->driver->hw_csr_reg(host, 3, 0, 0);
                else
                        ret = host->csr.channels_available_lo;

                *(buf++) = cpu_to_be32(ret);
                out;

	case CSR_BROADCAST_CHANNEL:
		*(buf++) = cpu_to_be32(host->csr.broadcast_channel);
		out;

                /* address gap to end - fall through to default */
        default:
                return RCODE_ADDRESS_ERROR;
        }

        return RCODE_COMPLETE;
}

static int write_regs(struct hpsb_host *host, int nodeid, int destid,
		      quadlet_t *data, u64 addr, size_t length, u16 flags)
{
        int csraddr = addr - CSR_REGISTER_BASE;

        if ((csraddr | length) & 0x3)
                return RCODE_TYPE_ERROR;

        length /= 4;

        switch (csraddr) {
        case CSR_STATE_CLEAR:
                /* FIXME FIXME FIXME */
                printk("doh, someone wants to mess with state clear\n");
                out;
        case CSR_STATE_SET:
                printk("doh, someone wants to mess with state set\n");
                out;

        case CSR_NODE_IDS:
                host->csr.node_ids &= NODE_MASK << 16;
                host->csr.node_ids |= be32_to_cpu(*(data++)) & (BUS_MASK << 16);
                host->node_id = host->csr.node_ids >> 16;
                host->driver->devctl(host, SET_BUS_ID, host->node_id >> 6);
                out;

        case CSR_RESET_START:
                /* FIXME - perform command reset */
                out;

                /* address gap */
                return RCODE_ADDRESS_ERROR;

        case CSR_SPLIT_TIMEOUT_HI:
                host->csr.split_timeout_hi =
                        be32_to_cpu(*(data++)) & 0x00000007;
		calculate_expire(&host->csr);
                out;
        case CSR_SPLIT_TIMEOUT_LO:
                host->csr.split_timeout_lo =
                        be32_to_cpu(*(data++)) & 0xfff80000;
		calculate_expire(&host->csr);
                out;

                /* address gap */
                return RCODE_ADDRESS_ERROR;

        case CSR_CYCLE_TIME:
                /* should only be set by cycle start packet, automatically */
                host->csr.cycle_time = be32_to_cpu(*data);
                host->driver->devctl(host, SET_CYCLE_COUNTER,
                                       be32_to_cpu(*(data++)));
                out;
        case CSR_BUS_TIME:
                host->csr.bus_time = be32_to_cpu(*(data++)) & 0xffffff80;
                out;

                /* address gap */
                return RCODE_ADDRESS_ERROR;

        case CSR_BUSY_TIMEOUT:
                /* not yet implemented */
                return RCODE_ADDRESS_ERROR;

        case CSR_BUS_MANAGER_ID:
        case CSR_BANDWIDTH_AVAILABLE:
        case CSR_CHANNELS_AVAILABLE_HI:
        case CSR_CHANNELS_AVAILABLE_LO:
                /* these are not writable, only lockable */
                return RCODE_TYPE_ERROR;

	case CSR_BROADCAST_CHANNEL:
		/* only the valid bit can be written */
		host->csr.broadcast_channel = (host->csr.broadcast_channel & ~0x40000000)
                        | (be32_to_cpu(*data) & 0x40000000);
		out;

                /* address gap to end - fall through */
        default:
                return RCODE_ADDRESS_ERROR;
        }

        return RCODE_COMPLETE;
}

#undef out


static int lock_regs(struct hpsb_host *host, int nodeid, quadlet_t *store,
                     u64 addr, quadlet_t data, quadlet_t arg, int extcode, u16 fl)
{
        int csraddr = addr - CSR_REGISTER_BASE;
        unsigned long flags;
        quadlet_t *regptr = NULL;

        if (csraddr & 0x3)
		return RCODE_TYPE_ERROR;

        if (csraddr < CSR_BUS_MANAGER_ID || csraddr > CSR_CHANNELS_AVAILABLE_LO
            || extcode != EXTCODE_COMPARE_SWAP)
                goto unsupported_lockreq;

        data = be32_to_cpu(data);
        arg = be32_to_cpu(arg);

	/* Is somebody releasing the broadcast_channel on us? */
	if (csraddr == CSR_CHANNELS_AVAILABLE_HI && (data & 0x1)) {
		/* Note: this is may not be the right way to handle
		 * the problem, so we should look into the proper way
		 * eventually. */
		HPSB_WARN("Node [" NODE_BUS_FMT "] wants to release "
			  "broadcast channel 31.  Ignoring.",
			  NODE_BUS_ARGS(host, nodeid));

		data &= ~0x1;	/* keep broadcast channel allocated */
	}

        if (host->driver->hw_csr_reg) {
                quadlet_t old;

                old = host->driver->
                        hw_csr_reg(host, (csraddr - CSR_BUS_MANAGER_ID) >> 2,
                                   data, arg);

                *store = cpu_to_be32(old);
                return RCODE_COMPLETE;
        }

        spin_lock_irqsave(&host->csr.lock, flags);

        switch (csraddr) {
        case CSR_BUS_MANAGER_ID:
                regptr = &host->csr.bus_manager_id;
		*store = cpu_to_be32(*regptr);
		if (*regptr == arg)
			*regptr = data;
                break;

        case CSR_BANDWIDTH_AVAILABLE:
        {
                quadlet_t bandwidth;
                quadlet_t old;
                quadlet_t new;

                regptr = &host->csr.bandwidth_available;
                old = *regptr;

                /* bandwidth available algorithm adapted from IEEE 1394a-2000 spec */
                if (arg > 0x1fff) {
                        *store = cpu_to_be32(old);	/* change nothing */
			break;
                }
                data &= 0x1fff;
                if (arg >= data) {
                        /* allocate bandwidth */
                        bandwidth = arg - data;
                        if (old >= bandwidth) {
                                new = old - bandwidth;
                                *store = cpu_to_be32(arg);
                                *regptr = new;
                        } else {
                                *store = cpu_to_be32(old);
                        }
                } else {
                        /* deallocate bandwidth */
                        bandwidth = data - arg;
                        if (old + bandwidth < 0x2000) {
                                new = old + bandwidth;
                                *store = cpu_to_be32(arg);
                                *regptr = new;
                        } else {
                                *store = cpu_to_be32(old);
                        }
                }
                break;
        }

        case CSR_CHANNELS_AVAILABLE_HI:
        {
                /* Lock algorithm for CHANNELS_AVAILABLE as recommended by 1394a-2000 */
                quadlet_t affected_channels = arg ^ data;

                regptr = &host->csr.channels_available_hi;

                if ((arg & affected_channels) == (*regptr & affected_channels)) {
                        *regptr ^= affected_channels;
                        *store = cpu_to_be32(arg);
                } else {
                        *store = cpu_to_be32(*regptr);
                }

                break;
        }

        case CSR_CHANNELS_AVAILABLE_LO:
        {
                /* Lock algorithm for CHANNELS_AVAILABLE as recommended by 1394a-2000 */
                quadlet_t affected_channels = arg ^ data;

                regptr = &host->csr.channels_available_lo;

                if ((arg & affected_channels) == (*regptr & affected_channels)) {
                        *regptr ^= affected_channels;
                        *store = cpu_to_be32(arg);
                } else {
                        *store = cpu_to_be32(*regptr);
                }
                break;
        }
        }

        spin_unlock_irqrestore(&host->csr.lock, flags);

        return RCODE_COMPLETE;

 unsupported_lockreq:
        switch (csraddr) {
        case CSR_STATE_CLEAR:
        case CSR_STATE_SET:
        case CSR_RESET_START:
        case CSR_NODE_IDS:
        case CSR_SPLIT_TIMEOUT_HI:
        case CSR_SPLIT_TIMEOUT_LO:
        case CSR_CYCLE_TIME:
        case CSR_BUS_TIME:
	case CSR_BROADCAST_CHANNEL:
                return RCODE_TYPE_ERROR;

        case CSR_BUSY_TIMEOUT:
                /* not yet implemented - fall through */
        default:
                return RCODE_ADDRESS_ERROR;
        }
}

static int lock64_regs(struct hpsb_host *host, int nodeid, octlet_t * store,
		       u64 addr, octlet_t data, octlet_t arg, int extcode, u16 fl)
{
	int csraddr = addr - CSR_REGISTER_BASE;
	unsigned long flags;

	data = be64_to_cpu(data);
	arg = be64_to_cpu(arg);

	if (csraddr & 0x3)
		return RCODE_TYPE_ERROR;

	if (csraddr != CSR_CHANNELS_AVAILABLE
	    || extcode != EXTCODE_COMPARE_SWAP)
		goto unsupported_lock64req;

	/* Is somebody releasing the broadcast_channel on us? */
	if (csraddr == CSR_CHANNELS_AVAILABLE_HI && (data & 0x100000000ULL)) {
		/* Note: this is may not be the right way to handle
		 * the problem, so we should look into the proper way
                 * eventually. */
		HPSB_WARN("Node [" NODE_BUS_FMT "] wants to release "
			  "broadcast channel 31.  Ignoring.",
			  NODE_BUS_ARGS(host, nodeid));

		data &= ~0x100000000ULL;	/* keep broadcast channel allocated */
	}

	if (host->driver->hw_csr_reg) {
		quadlet_t data_hi, data_lo;
		quadlet_t arg_hi, arg_lo;
		quadlet_t old_hi, old_lo;

		data_hi = data >> 32;
		data_lo = data & 0xFFFFFFFF;
		arg_hi = arg >> 32;
		arg_lo = arg & 0xFFFFFFFF;

		old_hi = host->driver->hw_csr_reg(host, (csraddr - CSR_BUS_MANAGER_ID) >> 2,
                                                  data_hi, arg_hi);

		old_lo = host->driver->hw_csr_reg(host, ((csraddr + 4) - CSR_BUS_MANAGER_ID) >> 2,
                                                  data_lo, arg_lo);

		*store = cpu_to_be64(((octlet_t)old_hi << 32) | old_lo);
	} else {
		octlet_t old;
		octlet_t affected_channels = arg ^ data;

		spin_lock_irqsave(&host->csr.lock, flags);

		old = ((octlet_t)host->csr.channels_available_hi << 32) | host->csr.channels_available_lo;

		if ((arg & affected_channels) == (old & affected_channels)) {
			host->csr.channels_available_hi ^= (affected_channels >> 32);
			host->csr.channels_available_lo ^= (affected_channels & 0xffffffff);
			*store = cpu_to_be64(arg);
		} else {
			*store = cpu_to_be64(old);
		}

		spin_unlock_irqrestore(&host->csr.lock, flags);
	}

	/* Is somebody erroneously releasing the broadcast_channel on us? */
	if (host->csr.channels_available_hi & 0x1)
		host->csr.channels_available_hi &= ~0x1;

	return RCODE_COMPLETE;

 unsupported_lock64req:
	switch (csraddr) {
	case CSR_STATE_CLEAR:
	case CSR_STATE_SET:
	case CSR_RESET_START:
	case CSR_NODE_IDS:
	case CSR_SPLIT_TIMEOUT_HI:
	case CSR_SPLIT_TIMEOUT_LO:
	case CSR_CYCLE_TIME:
	case CSR_BUS_TIME:
	case CSR_BUS_MANAGER_ID:
	case CSR_BROADCAST_CHANNEL:
	case CSR_BUSY_TIMEOUT:
	case CSR_BANDWIDTH_AVAILABLE:
		return RCODE_TYPE_ERROR;

	default:
		return RCODE_ADDRESS_ERROR;
	}
}

static int write_fcp(struct hpsb_host *host, int nodeid, int dest,
		     quadlet_t *data, u64 addr, size_t length, u16 flags)
{
        int csraddr = addr - CSR_REGISTER_BASE;

        if (length > 512)
                return RCODE_TYPE_ERROR;

        switch (csraddr) {
        case CSR_FCP_COMMAND:
                highlevel_fcp_request(host, nodeid, 0, (u8 *)data, length);
                break;
        case CSR_FCP_RESPONSE:
                highlevel_fcp_request(host, nodeid, 1, (u8 *)data, length);
                break;
        default:
                return RCODE_TYPE_ERROR;
        }

        return RCODE_COMPLETE;
}

static int read_config_rom(struct hpsb_host *host, int nodeid, quadlet_t *buffer,
			   u64 addr, size_t length, u16 fl)
{
	u32 offset = addr - CSR1212_REGISTER_SPACE_BASE;

	if (csr1212_read(host->csr.rom, offset, buffer, length) == CSR1212_SUCCESS)
		return RCODE_COMPLETE;
	else
		return RCODE_ADDRESS_ERROR;
}

static u64 allocate_addr_range(u64 size, u32 alignment, void *__host)
{
 	struct hpsb_host *host = (struct hpsb_host*)__host;

	return hpsb_allocate_and_register_addrspace(&csr_highlevel,
						    host,
						    &config_rom_ops,
						    size, alignment,
						    CSR1212_UNITS_SPACE_BASE,
						    CSR1212_UNITS_SPACE_END);
}

static void release_addr_range(u64 addr, void *__host)
{
 	struct hpsb_host *host = (struct hpsb_host*)__host;
	hpsb_unregister_addrspace(&csr_highlevel, host, addr);
}


int init_csr(void)
{
	node_cap = csr1212_new_immediate(CSR1212_KV_ID_NODE_CAPABILITIES, 0x0083c0);
	if (!node_cap) {
		HPSB_ERR("Failed to allocate memory for Node Capabilties ConfigROM entry!");
		return -ENOMEM;
	}

	hpsb_register_highlevel(&csr_highlevel);

	return 0;
}

void cleanup_csr(void)
{
	if (node_cap)
		csr1212_release_keyval(node_cap);
        hpsb_unregister_highlevel(&csr_highlevel);
}