1 // SPDX-License-Identifier: GPL-2.0
2 /* auxio.c: Probing for the Sparc AUXIO register at boot time.
3 *
4 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
5 */
6
7 #include <linux/stddef.h>
8 #include <linux/init.h>
9 #include <linux/spinlock.h>
10 #include <linux/of.h>
11 #include <linux/export.h>
12
13 #include <asm/oplib.h>
14 #include <asm/io.h>
15 #include <asm/auxio.h>
16 #include <asm/string.h> /* memset(), Linux has no bzero() */
17 #include <asm/cpu_type.h>
18
19 #include "kernel.h"
20
21 /* Probe and map in the Auxiliary I/O register */
22
23 /* auxio_register is not static because it is referenced
24 * in entry.S::floppy_tdone
25 */
26 void __iomem *auxio_register = NULL;
27 static DEFINE_SPINLOCK(auxio_lock);
28
auxio_probe(void)29 void __init auxio_probe(void)
30 {
31 phandle node, auxio_nd;
32 struct linux_prom_registers auxregs[1];
33 struct resource r;
34
35 switch (sparc_cpu_model) {
36 case sparc_leon:
37 case sun4d:
38 return;
39 default:
40 break;
41 }
42 node = prom_getchild(prom_root_node);
43 auxio_nd = prom_searchsiblings(node, "auxiliary-io");
44 if(!auxio_nd) {
45 node = prom_searchsiblings(node, "obio");
46 node = prom_getchild(node);
47 auxio_nd = prom_searchsiblings(node, "auxio");
48 if(!auxio_nd) {
49 #ifdef CONFIG_PCI
50 /* There may be auxio on Ebus */
51 return;
52 #else
53 if(prom_searchsiblings(node, "leds")) {
54 /* VME chassis sun4m machine, no auxio exists. */
55 return;
56 }
57 prom_printf("Cannot find auxio node, cannot continue...\n");
58 prom_halt();
59 #endif
60 }
61 }
62 if(prom_getproperty(auxio_nd, "reg", (char *) auxregs, sizeof(auxregs)) <= 0)
63 return;
64 prom_apply_obio_ranges(auxregs, 0x1);
65 /* Map the register both read and write */
66 r.flags = auxregs[0].which_io & 0xF;
67 r.start = auxregs[0].phys_addr;
68 r.end = auxregs[0].phys_addr + auxregs[0].reg_size - 1;
69 auxio_register = of_ioremap(&r, 0, auxregs[0].reg_size, "auxio");
70 /* Fix the address on sun4m. */
71 if ((((unsigned long) auxregs[0].phys_addr) & 3) == 3)
72 auxio_register += (3 - ((unsigned long)auxio_register & 3));
73
74 set_auxio(AUXIO_LED, 0);
75 }
76
get_auxio(void)77 unsigned char get_auxio(void)
78 {
79 if(auxio_register)
80 return sbus_readb(auxio_register);
81 return 0;
82 }
83 EXPORT_SYMBOL(get_auxio);
84
set_auxio(unsigned char bits_on,unsigned char bits_off)85 void set_auxio(unsigned char bits_on, unsigned char bits_off)
86 {
87 unsigned char regval;
88 unsigned long flags;
89 spin_lock_irqsave(&auxio_lock, flags);
90 switch (sparc_cpu_model) {
91 case sun4m:
92 if(!auxio_register)
93 break; /* VME chassis sun4m, no auxio. */
94 regval = sbus_readb(auxio_register);
95 sbus_writeb(((regval | bits_on) & ~bits_off) | AUXIO_ORMEIN4M,
96 auxio_register);
97 break;
98 case sun4d:
99 break;
100 default:
101 panic("Can't set AUXIO register on this machine.");
102 }
103 spin_unlock_irqrestore(&auxio_lock, flags);
104 }
105 EXPORT_SYMBOL(set_auxio);
106
107 /* sun4m power control register (AUXIO2) */
108
109 volatile u8 __iomem *auxio_power_register = NULL;
110
auxio_power_probe(void)111 void __init auxio_power_probe(void)
112 {
113 struct linux_prom_registers regs;
114 phandle node;
115 struct resource r;
116
117 /* Attempt to find the sun4m power control node. */
118 node = prom_getchild(prom_root_node);
119 node = prom_searchsiblings(node, "obio");
120 node = prom_getchild(node);
121 node = prom_searchsiblings(node, "power");
122 if (node == 0 || (s32)node == -1)
123 return;
124
125 /* Map the power control register. */
126 if (prom_getproperty(node, "reg", (char *)®s, sizeof(regs)) <= 0)
127 return;
128 prom_apply_obio_ranges(®s, 1);
129 memset(&r, 0, sizeof(r));
130 r.flags = regs.which_io & 0xF;
131 r.start = regs.phys_addr;
132 r.end = regs.phys_addr + regs.reg_size - 1;
133 auxio_power_register =
134 (u8 __iomem *)of_ioremap(&r, 0, regs.reg_size, "auxpower");
135
136 /* Display a quick message on the console. */
137 if (auxio_power_register)
138 printk(KERN_INFO "Power off control detected.\n");
139 }
140