staging/easycap: don't cast NULL pointer
[wandboard.git] / arch / sparc / kernel / starfire.c
blob82281a566bb86b866525a18b8fc4ca453d2e1e60
1 /*
2 * starfire.c: Starfire/E10000 support.
4 * Copyright (C) 1998 David S. Miller (davem@redhat.com)
5 * Copyright (C) 2000 Anton Blanchard (anton@samba.org)
6 */
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
11 #include <asm/page.h>
12 #include <asm/oplib.h>
13 #include <asm/smp.h>
14 #include <asm/upa.h>
15 #include <asm/starfire.h>
18 * A few places around the kernel check this to see if
19 * they need to call us to do things in a Starfire specific
20 * way.
22 int this_is_starfire = 0;
24 void check_if_starfire(void)
26 phandle ssnode = prom_finddevice("/ssp-serial");
27 if (ssnode != 0 && (s32)ssnode != -1)
28 this_is_starfire = 1;
31 int starfire_hard_smp_processor_id(void)
33 return upa_readl(0x1fff40000d0UL);
37 * Each Starfire board has 32 registers which perform translation
38 * and delivery of traditional interrupt packets into the extended
39 * Starfire hardware format. Essentially UPAID's now have 2 more
40 * bits than in all previous Sun5 systems.
42 struct starfire_irqinfo {
43 unsigned long imap_slots[32];
44 unsigned long tregs[32];
45 struct starfire_irqinfo *next;
46 int upaid, hwmid;
49 static struct starfire_irqinfo *sflist = NULL;
51 /* Beam me up Scott(McNeil)y... */
52 void starfire_hookup(int upaid)
54 struct starfire_irqinfo *p;
55 unsigned long treg_base, hwmid, i;
57 p = kmalloc(sizeof(*p), GFP_KERNEL);
58 if (!p) {
59 prom_printf("starfire_hookup: No memory, this is insane.\n");
60 prom_halt();
62 treg_base = 0x100fc000000UL;
63 hwmid = ((upaid & 0x3c) << 1) |
64 ((upaid & 0x40) >> 4) |
65 (upaid & 0x3);
66 p->hwmid = hwmid;
67 treg_base += (hwmid << 33UL);
68 treg_base += 0x200UL;
69 for (i = 0; i < 32; i++) {
70 p->imap_slots[i] = 0UL;
71 p->tregs[i] = treg_base + (i * 0x10UL);
72 /* Lets play it safe and not overwrite existing mappings */
73 if (upa_readl(p->tregs[i]) != 0)
74 p->imap_slots[i] = 0xdeadbeaf;
76 p->upaid = upaid;
77 p->next = sflist;
78 sflist = p;
81 unsigned int starfire_translate(unsigned long imap,
82 unsigned int upaid)
84 struct starfire_irqinfo *p;
85 unsigned int bus_hwmid;
86 unsigned int i;
88 bus_hwmid = (((unsigned long)imap) >> 33) & 0x7f;
89 for (p = sflist; p != NULL; p = p->next)
90 if (p->hwmid == bus_hwmid)
91 break;
92 if (p == NULL) {
93 prom_printf("XFIRE: Cannot find irqinfo for imap %016lx\n",
94 ((unsigned long)imap));
95 prom_halt();
97 for (i = 0; i < 32; i++) {
98 if (p->imap_slots[i] == imap ||
99 p->imap_slots[i] == 0UL)
100 break;
102 if (i == 32) {
103 printk("starfire_translate: Are you kidding me?\n");
104 panic("Lucy in the sky....");
106 p->imap_slots[i] = imap;
108 /* map to real upaid */
109 upaid = (((upaid & 0x3c) << 1) |
110 ((upaid & 0x40) >> 4) |
111 (upaid & 0x3));
113 upa_writel(upaid, p->tregs[i]);
115 return i;