xref: /openbmc/linux/arch/sparc/kernel/starfire.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * starfire.c: Starfire/E10000 support.
4  *
5  * Copyright (C) 1998 David S. Miller (davem@redhat.com)
6  * Copyright (C) 2000 Anton Blanchard (anton@samba.org)
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 
12 #include <asm/page.h>
13 #include <asm/oplib.h>
14 #include <asm/smp.h>
15 #include <asm/upa.h>
16 #include <asm/starfire.h>
17 
18 /*
19  * A few places around the kernel check this to see if
20  * they need to call us to do things in a Starfire specific
21  * way.
22  */
23 int this_is_starfire = 0;
24 
25 void check_if_starfire(void)
26 {
27 	phandle ssnode = prom_finddevice("/ssp-serial");
28 	if (ssnode != 0 && (s32)ssnode != -1)
29 		this_is_starfire = 1;
30 }
31 
32 /*
33  * Each Starfire board has 32 registers which perform translation
34  * and delivery of traditional interrupt packets into the extended
35  * Starfire hardware format.  Essentially UPAID's now have 2 more
36  * bits than in all previous Sun5 systems.
37  */
38 struct starfire_irqinfo {
39 	unsigned long imap_slots[32];
40 	unsigned long tregs[32];
41 	struct starfire_irqinfo *next;
42 	int upaid, hwmid;
43 };
44 
45 static struct starfire_irqinfo *sflist = NULL;
46 
47 /* Beam me up Scott(McNeil)y... */
48 void starfire_hookup(int upaid)
49 {
50 	struct starfire_irqinfo *p;
51 	unsigned long treg_base, hwmid, i;
52 
53 	p = kmalloc(sizeof(*p), GFP_KERNEL);
54 	if (!p) {
55 		prom_printf("starfire_hookup: No memory, this is insane.\n");
56 		prom_halt();
57 	}
58 	treg_base = 0x100fc000000UL;
59 	hwmid = ((upaid & 0x3c) << 1) |
60 		((upaid & 0x40) >> 4) |
61 		(upaid & 0x3);
62 	p->hwmid = hwmid;
63 	treg_base += (hwmid << 33UL);
64 	treg_base += 0x200UL;
65 	for (i = 0; i < 32; i++) {
66 		p->imap_slots[i] = 0UL;
67 		p->tregs[i] = treg_base + (i * 0x10UL);
68 		/* Lets play it safe and not overwrite existing mappings */
69 		if (upa_readl(p->tregs[i]) != 0)
70 			p->imap_slots[i] = 0xdeadbeaf;
71 	}
72 	p->upaid = upaid;
73 	p->next = sflist;
74 	sflist = p;
75 }
76 
77 unsigned int starfire_translate(unsigned long imap,
78 				unsigned int upaid)
79 {
80 	struct starfire_irqinfo *p;
81 	unsigned int bus_hwmid;
82 	unsigned int i;
83 
84 	bus_hwmid = (((unsigned long)imap) >> 33) & 0x7f;
85 	for (p = sflist; p != NULL; p = p->next)
86 		if (p->hwmid == bus_hwmid)
87 			break;
88 	if (p == NULL) {
89 		prom_printf("XFIRE: Cannot find irqinfo for imap %016lx\n",
90 			    ((unsigned long)imap));
91 		prom_halt();
92 	}
93 	for (i = 0; i < 32; i++) {
94 		if (p->imap_slots[i] == imap ||
95 		    p->imap_slots[i] == 0UL)
96 			break;
97 	}
98 	if (i == 32) {
99 		printk("starfire_translate: Are you kidding me?\n");
100 		panic("Lucy in the sky....");
101 	}
102 	p->imap_slots[i] = imap;
103 
104 	/* map to real upaid */
105 	upaid = (((upaid & 0x3c) << 1) |
106 		 ((upaid & 0x40) >> 4) |
107 		 (upaid & 0x3));
108 
109 	upa_writel(upaid, p->tregs[i]);
110 
111 	return i;
112 }
113