xref: /openbmc/linux/arch/mips/sgi-ip27/ip27-xtalk.c (revision e23feb16)
1 /*
2  * Copyright (C) 1999, 2000 Ralf Baechle (ralf@gnu.org)
3  * Copyright (C) 1999, 2000 Silcon Graphics, Inc.
4  * Copyright (C) 2004 Christoph Hellwig.
5  *	Released under GPL v2.
6  *
7  * Generic XTALK initialization code
8  */
9 
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/smp.h>
13 #include <asm/sn/types.h>
14 #include <asm/sn/klconfig.h>
15 #include <asm/sn/hub.h>
16 #include <asm/pci/bridge.h>
17 #include <asm/xtalk/xtalk.h>
18 
19 
20 #define XBOW_WIDGET_PART_NUM	0x0
21 #define XXBOW_WIDGET_PART_NUM	0xd000	/* Xbow in Xbridge */
22 #define BASE_XBOW_PORT		8     /* Lowest external port */
23 
24 extern int bridge_probe(nasid_t nasid, int widget, int masterwid);
25 
26 static int probe_one_port(nasid_t nasid, int widget, int masterwid)
27 {
28 	widgetreg_t		widget_id;
29 	xwidget_part_num_t	partnum;
30 
31 	widget_id = *(volatile widgetreg_t *)
32 		(RAW_NODE_SWIN_BASE(nasid, widget) + WIDGET_ID);
33 	partnum = XWIDGET_PART_NUM(widget_id);
34 
35 	printk(KERN_INFO "Cpu %d, Nasid 0x%x, widget 0x%x (partnum 0x%x) is ",
36 			smp_processor_id(), nasid, widget, partnum);
37 
38 	switch (partnum) {
39 	case BRIDGE_WIDGET_PART_NUM:
40 	case XBRIDGE_WIDGET_PART_NUM:
41 		bridge_probe(nasid, widget, masterwid);
42 		break;
43 	default:
44 		break;
45 	}
46 
47 	return 0;
48 }
49 
50 static int xbow_probe(nasid_t nasid)
51 {
52 	lboard_t *brd;
53 	klxbow_t *xbow_p;
54 	unsigned masterwid, i;
55 
56 	printk("is xbow\n");
57 
58 	/*
59 	 * found xbow, so may have multiple bridges
60 	 * need to probe xbow
61 	 */
62 	brd = find_lboard((lboard_t *)KL_CONFIG_INFO(nasid), KLTYPE_MIDPLANE8);
63 	if (!brd)
64 		return -ENODEV;
65 
66 	xbow_p = (klxbow_t *)find_component(brd, NULL, KLSTRUCT_XBOW);
67 	if (!xbow_p)
68 		return -ENODEV;
69 
70 	/*
71 	 * Okay, here's a xbow. Lets arbitrate and find
72 	 * out if we should initialize it. Set enabled
73 	 * hub connected at highest or lowest widget as
74 	 * master.
75 	 */
76 #ifdef WIDGET_A
77 	i = HUB_WIDGET_ID_MAX + 1;
78 	do {
79 		i--;
80 	} while ((!XBOW_PORT_TYPE_HUB(xbow_p, i)) ||
81 		 (!XBOW_PORT_IS_ENABLED(xbow_p, i)));
82 #else
83 	i = HUB_WIDGET_ID_MIN - 1;
84 	do {
85 		i++;
86 	} while ((!XBOW_PORT_TYPE_HUB(xbow_p, i)) ||
87 		 (!XBOW_PORT_IS_ENABLED(xbow_p, i)));
88 #endif
89 
90 	masterwid = i;
91 	if (nasid != XBOW_PORT_NASID(xbow_p, i))
92 		return 1;
93 
94 	for (i = HUB_WIDGET_ID_MIN; i <= HUB_WIDGET_ID_MAX; i++) {
95 		if (XBOW_PORT_IS_ENABLED(xbow_p, i) &&
96 		    XBOW_PORT_TYPE_IO(xbow_p, i))
97 			probe_one_port(nasid, i, masterwid);
98 	}
99 
100 	return 0;
101 }
102 
103 void xtalk_probe_node(cnodeid_t nid)
104 {
105 	volatile u64		hubreg;
106 	nasid_t			nasid;
107 	xwidget_part_num_t	partnum;
108 	widgetreg_t		widget_id;
109 
110 	nasid = COMPACT_TO_NASID_NODEID(nid);
111 	hubreg = REMOTE_HUB_L(nasid, IIO_LLP_CSR);
112 
113 	/* check whether the link is up */
114 	if (!(hubreg & IIO_LLP_CSR_IS_UP))
115 		return;
116 
117 	widget_id = *(volatile widgetreg_t *)
118 		       (RAW_NODE_SWIN_BASE(nasid, 0x0) + WIDGET_ID);
119 	partnum = XWIDGET_PART_NUM(widget_id);
120 
121 	printk(KERN_INFO "Cpu %d, Nasid 0x%x: partnum 0x%x is ",
122 			smp_processor_id(), nasid, partnum);
123 
124 	switch (partnum) {
125 	case BRIDGE_WIDGET_PART_NUM:
126 		bridge_probe(nasid, 0x8, 0xa);
127 		break;
128 	case XBOW_WIDGET_PART_NUM:
129 	case XXBOW_WIDGET_PART_NUM:
130 		xbow_probe(nasid);
131 		break;
132 	default:
133 		printk(" unknown widget??\n");
134 		break;
135 	}
136 }
137