aboutsummaryrefslogtreecommitdiff
path: root/src/northbridge/amd/amdk8/coherent_ht.c
blob: 25779a2bf2501e25a20a747dc182c0e7a9af8cd1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
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
/* coherent hypertransport initialization for AMD64 
 * 
 * written by Stefan Reinauer <stepan@openbios.org>
 * (c) 2003-2004 by SuSE Linux AG
 *
 * This code is licensed under GPL.
 */

/*
 * This algorithm assumes a grid configuration as follows:
 *
 * nodes :  1    2    4    6    8
 * org.  :  1x1  2x1  2x2  2x3  2x4
 *
 */

#include <device/pci_def.h>
#include <device/pci_ids.h>
#include <device/hypertransport_def.h>
#include "arch/romcc_io.h"
#include "amdk8.h"

/* when generating a temporary row configuration we
 * don't want broadcast to be enabled for that node.
 */

#define generate_temp_row(...) ((generate_row(__VA_ARGS__)&(~0x0f0000))|0x010000)
#define clear_temp_row(x)       fill_row(x,7,DEFAULT)
#define enable_bsp_routing()	enable_routing(0)

#define NODE_HT(x) PCI_DEV(0,24+x,0)
#define NODE_MP(x) PCI_DEV(0,24+x,1)
#define NODE_MC(x) PCI_DEV(0,24+x,3)

#define DEFAULT 0x00010101	/* default row entry */

typedef uint8_t u8;
typedef uint32_t u32;
typedef int bool;

#define TRUE  (-1)
#define FALSE (0)

static u8 link_to_register(int ldt)
{
	/*
	 * [ 0: 3] Request Route
	 *     [0] Route to this node
	 *     [1] Route to Link 0
	 *     [2] Route to Link 1
	 *     [3] Route to Link 2
	 */

	if (ldt&0x08) return 0x40;
	if (ldt&0x04) return 0x20;
	if (ldt&0x02) return 0x00;
	
	/* we should never get here */
	print_debug("Unknown Link\n");
	return 0;
}

static int link_connection(int src, int dest)
{
	/* we generate the needed link information from the rows
	 * by taking the Request Route of the according row.
	 */
	
	return generate_row(src, dest, CONFIG_MAX_CPUS) & 0x0f;
}

static void disable_probes(void)
{
	/* disable read/write/fill probes for uniprocessor setup
	 * they don't make sense if only one cpu is available
	 */

	/* Hypetransport Transaction Control Register 
	 * F0:0x68
	 * [ 0: 0] Disable read byte probe
	 *         0 = Probes issues
	 *         1 = Probes not issued
	 * [ 1: 1] Disable Read Doubleword probe
	 *         0 = Probes issued
	 *         1 = Probes not issued
	 * [ 2: 2] Disable write byte probes
	 *         0 = Probes issued
	 *         1 = Probes not issued
	 * [ 3: 3] Disable Write Doubleword Probes
	 *         0 = Probes issued
	 *         1 = Probes not issued.
	 * [10:10] Disable Fill Probe
	 *         0 = Probes issued for cache fills
	 *         1 = Probes not issued for cache fills.
	 */

	u32 val;

	print_spew("Disabling read/write/fill probes for UP... ");

	val=pci_read_config32(NODE_HT(0), 0x68);
	val |= (1<<10)|(1<<9)|(1<<8)|(1<<4)|(1<<3)|(1<<2)|(1<<1)|(1 << 0);
	pci_write_config32(NODE_HT(0), 0x68, val);

	print_spew("done.\r\n");

}

static void enable_routing(u8 node)
{
	u32 val;

	/* HT Initialization Control Register
	 * F0:0x6C
	 * [ 0: 0] Routing Table Disable
	 *         0 = Packets are routed according to routing tables
	 *         1 = Packets are routed according to the default link field
	 * [ 1: 1] Request Disable (BSP should clear this)
	 *         0 = Request packets may be generated
	 *         1 = Request packets may not be generated.
	 * [ 3: 2] Default Link (Read-only)
	 *         00 = LDT0
	 *         01 = LDT1
	 *         10 = LDT2
	 *         11 = CPU on same node
	 * [ 4: 4] Cold Reset
	 *         - Scratch bit cleared by a cold reset
	 * [ 5: 5] BIOS Reset Detect
	 *         - Scratch bit cleared by a cold reset
	 * [ 6: 6] INIT Detect
	 *         - Scratch bit cleared by a warm or cold reset not by an INIT
	 *
	 */

	/* Enable routing table */
	print_spew("Enabling routing table for node ");
	print_spew_hex8(node);

	val=pci_read_config32(NODE_HT(node), 0x6c);
	val &= ~((1<<1)|(1<<0));
	pci_write_config32(NODE_HT(node), 0x6c, val);

	print_spew(" done.\r\n");
}

#if CONFIG_MAX_CPUS > 1

static void rename_temp_node(u8 node)
{
	uint32_t val;

	print_spew("Renaming current temporary node to ");
	print_spew_hex8(node);

	val=pci_read_config32(NODE_HT(7), 0x60);
	val &= (~7);  /* clear low bits. */
        val |= node;   /* new node        */
	pci_write_config32(NODE_HT(7), 0x60, val);

	print_spew(" done.\r\n");
}

static bool check_connection(u8 src, u8 dest, u8 link)
{
	/* See if we have a valid connection to dest */
	u32 val;
	
	/* Detect if the coherent HT link is connected. */
	val = pci_read_config32(NODE_HT(src), 0x98+link);
	if ( (val&0x17) != 0x03)
		return 0;

	/* Verify that the coherent hypertransport link is
	 * established and actually working by reading the
	 * remode node's vendor/device id
	 */
        val = pci_read_config32(NODE_HT(dest),0);
	if(val != 0x11001022)
		return 0;

	return 1;
}

static unsigned read_freq_cap(device_t dev, unsigned pos)
{
	/* Handle bugs in valid hypertransport frequency reporting */
	unsigned freq_cap;
	uint32_t id;

	freq_cap = pci_read_config16(dev, pos);
	freq_cap &= ~(1 << HT_FREQ_VENDOR); /* Ignore Vendor HT frequencies */

	id = pci_read_config32(dev, 0);

	/* AMD 8131 Errata 48 */
	if (id == (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_AMD_8131_PCIX << 16))) {
		freq_cap &= ~(1 << HT_FREQ_800Mhz);
	}
	/* AMD 8151 Errata 23 */
	if (id == (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_AMD_8151_SYSCTRL << 16))) {
		freq_cap &= ~(1 << HT_FREQ_800Mhz);
	}
	/* AMD K8 Unsupported 1Ghz? */
	if (id == (PCI_VENDOR_ID_AMD | (0x1100 << 16))) {
		freq_cap &= ~(1 << HT_FREQ_1000Mhz);
	}
	return freq_cap;
}

static int optimize_connection(device_t node1, uint8_t link1, device_t node2, uint8_t link2)
{
	static const uint8_t link_width_to_pow2[]= { 3, 4, 0, 5, 1, 2, 0, 0 };
	static const uint8_t pow2_to_link_width[] = { 0x7, 4, 5, 0, 1, 3 };
	uint16_t freq_cap1, freq_cap2, freq_cap, freq_mask;
	uint8_t width_cap1, width_cap2, width_cap, width, old_width, ln_width1, ln_width2;
	uint8_t freq, old_freq;
	int needs_reset;
	/* Set link width and frequency */

	/* Initially assume everything is already optimized and I don't need a reset */
	needs_reset = 0;

	/* Get the frequency capabilities */
	freq_cap1 = read_freq_cap(node1, link1 + PCI_HT_CAP_HOST_FREQ_CAP);
	freq_cap2 = read_freq_cap(node2, link2 + PCI_HT_CAP_HOST_FREQ_CAP);

	/* Calculate the highest possible frequency */
	freq = log2(freq_cap1 & freq_cap2);

	/* See if I am changing the link freqency */
	old_freq = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_FREQ);
	needs_reset |= old_freq != freq;
	old_freq = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_FREQ);
	needs_reset |= old_freq != freq;

	/* Set the Calulcated link frequency */
	pci_write_config8(node1, link1 + PCI_HT_CAP_HOST_FREQ, freq);
	pci_write_config8(node2, link2 + PCI_HT_CAP_HOST_FREQ, freq);

	/* Get the width capabilities */
	width_cap1 = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH);
	width_cap2 = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH);

	/* Calculate node1's input width */
	ln_width1 = link_width_to_pow2[width_cap1 & 7];
	ln_width2 = link_width_to_pow2[(width_cap2 >> 4) & 7];
	if (ln_width1 > ln_width2) {
		ln_width1 = ln_width2;
	}
	width = pow2_to_link_width[ln_width1];
	/* Calculate node1's output width */
	ln_width1 = link_width_to_pow2[(width_cap1 >> 4) & 7];
	ln_width2 = link_width_to_pow2[width_cap2 & 7];
	if (ln_width1 > ln_width2) {
		ln_width1 = ln_width2;
	}
	width |= pow2_to_link_width[ln_width1] << 4;
	
	/* See if I am changing node1's width */
	old_width = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH + 1);
	needs_reset |= old_width != width;

	/* Set node1's widths */
	pci_write_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH + 1, width);

	/* Calculate node2's width */
	width = ((width & 0x70) >> 4) | ((width & 0x7) << 4);

	/* See if I am changing node2's width */
	old_width = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH + 1);
	needs_reset |= old_width != width;

	/* Set node2's widths */
	pci_write_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH + 1, width);

	return needs_reset;
}

static void fill_row(u8 node, u8 row, u32 value)
{
	pci_write_config32(NODE_HT(node), 0x40+(row<<2), value);
}

static void setup_row(u8 source, u8 dest, u8 cpus)
{
	fill_row(source,dest,generate_row(source,dest,cpus));
}

static void setup_temp_row(u8 source, u8 dest, u8 cpus)
{
	fill_row(source,7,generate_temp_row(source,dest,cpus));
}

static void setup_node(u8 node, u8 cpus)
{
	u8 row;
	for(row=0; row<cpus; row++)
		setup_row(node, row, cpus);
}

static void setup_remote_row(u8 source, u8 dest, u8 cpus)
{
	fill_row(7, dest, generate_row(source, dest, cpus));
}

static void setup_remote_node(u8 node, u8 cpus)
{
	static const uint8_t pci_reg[] = { 
		0x44, 0x4c, 0x54, 0x5c, 0x64, 0x6c, 0x74, 0x7c, 
		0x40, 0x48, 0x50, 0x58, 0x60, 0x68, 0x70, 0x78,
		0x84, 0x8c, 0x94, 0x9c, 0xa4, 0xac, 0xb4, 0xbc,
		0x80, 0x88, 0x90, 0x98, 0xa0, 0xa8, 0xb0, 0xb8,
		0xc4, 0xcc, 0xd4, 0xdc,
		0xc0, 0xc8, 0xd0, 0xd8,
		0xe0, 0xe4, 0xe8, 0xec,
	};
	uint8_t row;
	int i;

	print_spew("setup_remote_node: ");
	for(row=0; row<cpus; row++)
		setup_remote_row(node, row, cpus);

	/* copy the default resource map from node 0 */
	for(i = 0; i < sizeof(pci_reg)/sizeof(pci_reg[0]); i++) {
		uint32_t value;
		uint8_t reg;
		reg = pci_reg[i];
		value = pci_read_config32(NODE_MP(0), reg);
		pci_write_config32(NODE_MP(7), reg, value);

	}
	print_spew("done\r\n");
}

#endif

#if CONFIG_MAX_CPUS > 2
static void setup_temp_node(u8 node, u8 cpus)
{
	u8 row;
	for(row=0; row<cpus; row++)
		fill_row(7,row,generate_row(node,row,cpus));
}
#endif

static void setup_uniprocessor(void)
{
	print_spew("Enabling UP settings\r\n");
	disable_probes();
}

struct setup_smp_result {
	int cpus;
	int needs_reset;
};

#if CONFIG_MAX_CPUS > 1
static struct setup_smp_result setup_smp(void)
{
	struct setup_smp_result result;
	result.cpus = 2;
	result.needs_reset = 0;

	print_spew("Enabling SMP settings\r\n");

	setup_row(0, 0, result.cpus);
	/* Setup and check a temporary connection to node 1 */
	setup_temp_row(0, 1, result.cpus);
	
	if (!check_connection(0, 7, link_to_register(link_connection(0,1)))) {
		print_debug("No connection to Node 1.\r\n");
		clear_temp_row(0);	/* delete temp connection */
		setup_uniprocessor();	/* and get up working     */
		result.cpus = 1;
		return result;
	}

	/* We found 2 nodes so far */
	
	setup_node(0, result.cpus);	/* Node 1 is there. Setup Node 0 correctly */
	setup_remote_node(1, result.cpus);  /* Setup the routes on the remote node */
        rename_temp_node(1);    /* Rename Node 7 to Node 1  */
        enable_routing(1);      /* Enable routing on Node 1 */
  	
	clear_temp_row(0);	/* delete temporary connection */
	
	result.needs_reset =
		optimize_connection(NODE_HT(0), 0x80 + link_to_register(link_connection(0,1)),
				    NODE_HT(1), 0x80 + link_to_register(link_connection(1,0)) );

#if CONFIG_MAX_CPUS > 2
	result.cpus=4;
	
	/* Setup and check temporary connection from Node 0 to Node 2 */
	setup_temp_row(0,2, result.cpus);

	if (!check_connection(0, 7, link_to_register(link_connection(0,2))) ) {
		print_debug("No connection to Node 2.\r\n");
		clear_temp_row(0);	 /* delete temp connection */
		result.cpus = 2;
		return result;
	}

	/* We found 3 nodes so far. Now setup a temporary
	 * connection from node 0 to node 3 via node 1
	 */

	setup_temp_row(0,1, result.cpus); /* temp. link between nodes 0 and 1 */
	setup_temp_row(1,3, result.cpus); /* temp. link between nodes 1 and 3 */

	if (!check_connection(1, 7, link_to_register(link_connection(1,3)))) {
		print_debug("No connection to Node 3.\r\n");
		clear_temp_row(0);	 /* delete temp connection */
		clear_temp_row(1);	 /* delete temp connection */
		result.cpus = 2;
		return result;
	}

	/* We found 4 nodes so far. Now setup all nodes for 4p */

	setup_node(0, result.cpus);  /* The first 2 nodes are configured    */
	setup_node(1, result.cpus);  /* already. Just configure them for 4p */
	
	setup_temp_row(0,2, result.cpus);
	setup_temp_node(2, result.cpus);
        rename_temp_node(2);
        enable_routing(2);
  
	setup_temp_row(0,1, result.cpus);
	setup_temp_row(1,3, result.cpus);
	setup_temp_node(3, result.cpus);
        rename_temp_node(3);
        enable_routing(3);      /* enable routing on node 3 (temp.) */
	
	clear_temp_row(0);
	clear_temp_row(1);
	clear_temp_row(2);
	clear_temp_row(3);

	/* optimize physical connections - by LYH */
	result.needs_reset = optimize_connection(
		NODE_HT(0), 0x80 + link_to_register(link_connection(0,2)),
		NODE_HT(2), 0x80 + link_to_register(link_connection(2,0)) );

	result.needs_reset = optimize_connection(
		NODE_HT(1), 0x80 + link_to_register(link_connection(1,3)),
		NODE_HT(3), 0x80 + link_to_register(link_connection(3,1)) );

	result.needs_reset = optimize_connection(
		NODE_HT(2), 0x80 + link_to_register(link_connection(2,3)),
		NODE_HT(3), 0x80 + link_to_register(link_connection(3,2)) );

#endif /* CONFIG_MAX_CPUS > 2 */

	print_debug_hex8(result.cpus);
	print_debug(" nodes initialized.\r\n");
	return result;
}
#endif

#if CONFIG_MAX_CPUS > 1
static unsigned verify_mp_capabilities(unsigned cpus)
{
	unsigned node, row, mask;
	bool mp_cap=TRUE;

	if (cpus > 2) {
		mask=0x06;	/* BigMPCap */
	} else {
		mask=0x02;	/* MPCap    */
	}

	for (node=0; node<cpus; node++) {
		if ((pci_read_config32(NODE_MC(node), 0xe8) & mask) != mask) {
			mp_cap = FALSE;
		}
	}

	if (mp_cap) {
		return cpus;
	}

	/* one of our cpus is not mp capable */

	print_err("One of the CPUs is not MP capable. Going back to UP\r\n");

	for (node = cpus; node > 0; node--) {
		for (row = cpus; row > 0; row--) {
			fill_row(NODE_HT(node-1), row-1, DEFAULT);
		}
	}
	setup_uniprocessor();
	return 1;
}

#endif

static void coherent_ht_finalize(unsigned cpus)
{
	unsigned node;
	bool rev_a0;
	
	/* set up cpu count and node count and enable Limit
	 * Config Space Range for all available CPUs.
	 * Also clear non coherent hypertransport bus range
	 * registers on Hammer A0 revision.
	 */

#if 1
	print_debug("coherent_ht_finalize\r\n");
#endif
	rev_a0 = is_cpu_rev_a0();
	for (node = 0; node < cpus; node++) {
		device_t dev;
		uint32_t val;
		dev = NODE_HT(node);

		/* Set the Total CPU and Node count in the system */
		val = pci_read_config32(dev, 0x60);
		val &= (~0x000F0070);
		val |= ((cpus-1)<<16)|((cpus-1)<<4);
		pci_write_config32(dev, 0x60, val);

		/* Only respond to real cpu pci configuration cycles
		 * and optimize the HT settings 
		 */
		val=pci_read_config32(dev, 0x68);
		val &= ~((HTTC_BUF_REL_PRI_MASK << HTTC_BUF_REL_PRI_SHIFT) |
			(HTTC_MED_PRI_BYP_CNT_MASK << HTTC_MED_PRI_BYP_CNT_SHIFT) |
			(HTTC_HI_PRI_BYP_CNT_MASK << HTTC_HI_PRI_BYP_CNT_SHIFT));
		val |= HTTC_LIMIT_CLDT_CFG | 
			(HTTC_BUF_REL_PRI_8 << HTTC_BUF_REL_PRI_SHIFT) |
			HTTC_RSP_PASS_PW |
			(3 << HTTC_MED_PRI_BYP_CNT_SHIFT) |
			(3 << HTTC_HI_PRI_BYP_CNT_SHIFT);
		pci_write_config32(dev, 0x68, val);

		if (rev_a0) {
			print_debug("shit it is an old cup\n");
			pci_write_config32(dev, 0x94, 0);
			pci_write_config32(dev, 0xb4, 0);
			pci_write_config32(dev, 0xd4, 0);
		}
	}

#if 1
	print_debug("done\r\n");
#endif
}

static int apply_cpu_errata_fixes(unsigned cpus, int needs_reset)
{
	unsigned node;
	for(node = 0; node < cpus; node++) {
		device_t dev;
		uint32_t cmd;
		dev = NODE_MC(node);
		if (is_cpu_pre_c0()) {

			/* Errata 66
			 * Limit the number of downstream posted requests to 1 
			 */
			cmd = pci_read_config32(dev, 0x70);
			if ((cmd & (3 << 0)) != 2) {
				cmd &= ~(3<<0);
				cmd |= (2<<0);
				pci_write_config32(dev, 0x70, cmd );
				needs_reset = 1;
			}
			cmd = pci_read_config32(dev, 0x7c);
			if ((cmd & (3 << 4)) != 0) {
				cmd &= ~(3<<4);
				cmd |= (0<<4);
				pci_write_config32(dev, 0x7c, cmd );
				needs_reset = 1;
			}
			/* Clock Power/Timing Low */
			cmd = pci_read_config32(dev, 0xd4);
			if (cmd != 0x000D0001) {
				cmd = 0x000D0001;
				pci_write_config32(dev, 0xd4, cmd);
				needs_reset = 1; /* Needed? */
			}

		}
		else {
			uint32_t cmd_ref;
			/* Errata 98 
			 * Set Clk Ramp Hystersis to 7
			 * Clock Power/Timing Low
			 */
			cmd_ref = 0x04e20707; /* Registered */
			cmd = pci_read_config32(dev, 0xd4);
			if(cmd != cmd_ref) {
				pci_write_config32(dev, 0xd4, cmd_ref );
				needs_reset = 1; /* Needed? */
			}
		}
	}
	return needs_reset;
}

static int optimize_link_read_pointers(unsigned cpus, int needs_reset)
{
	unsigned node;
	for(node = 0; node < cpus; node = node + 1) {
		device_t f0_dev, f3_dev;
		uint32_t cmd_ref, cmd;
		int link;
		f0_dev = NODE_HT(node);
		f3_dev = NODE_MC(node);
		cmd_ref = cmd = pci_read_config32(f3_dev, 0xdc);
		for(link = 0; link < 3; link = link + 1) {
			uint32_t link_type;
			unsigned reg;
			reg = 0x98 + (link * 0x20);
			link_type = pci_read_config32(f0_dev, reg);
			if (link_type & LinkConnected) {
				cmd &= 0xff << (link *8);
				/* FIXME this assumes the device on the other
				 * side is an AMD device */
				cmd |= 0x25 << (link *8);
			}
		}
		if (cmd != cmd_ref) {
			pci_write_config32(f3_dev, 0xdc, cmd);
			needs_reset = 1;
		}
	}
	return needs_reset;
}

static int setup_coherent_ht_domain(void)
{
	struct setup_smp_result result;
	result.cpus = 1;
	result.needs_reset = 0;

	enable_bsp_routing();

#if CONFIG_MAX_CPUS == 1
	setup_uniprocessor();
#else
	result = setup_smp();
	result.cpus = verify_mp_capabilities(result.cpus);
#endif

	coherent_ht_finalize(result.cpus);
	result.needs_reset = apply_cpu_errata_fixes(result.cpus, result.needs_reset);

#if CONFIG_MAX_CPUS > 1 /* Why doesn't this work on the solo? */
	result.needs_reset = optimize_link_read_pointers(result.cpus, result.needs_reset);
#endif

	return result.needs_reset;
}