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/of_device.h>
12 #include <linux/export.h>
13
14 #include <asm/oplib.h>
15 #include <asm/io.h>
16 #include <asm/auxio.h>
17 #include <asm/string.h> /* memset(), Linux has no bzero() */
18 #include <asm/cpu_type.h>
19
20 #include "kernel.h"
21
22 /* Probe and map in the Auxiliary I/O register */
23
24 /* auxio_register is not static because it is referenced
25 * in entry.S::floppy_tdone
26 */
27 void __iomem *auxio_register = NULL;
28 static DEFINE_SPINLOCK(auxio_lock);
29
auxio_probe(void)30 void __init auxio_probe(void)
31 {
32 phandle node, auxio_nd;
33 struct linux_prom_registers auxregs[1];
34 struct resource r;
35
36 switch (sparc_cpu_model) {
37 case sparc_leon:
38 case sun4d:
39 return;
40 default:
41 break;
42 }
43 node = prom_getchild(prom_root_node);
44 auxio_nd = prom_searchsiblings(node, "auxiliary-io");
45 if(!auxio_nd) {
46 node = prom_searchsiblings(node, "obio");
47 node = prom_getchild(node);
48 auxio_nd = prom_searchsiblings(node, "auxio");
49 if(!auxio_nd) {
50 #ifdef CONFIG_PCI
51 /* There may be auxio on Ebus */
52 return;
53 #else
54 if(prom_searchsiblings(node, "leds")) {
55 /* VME chassis sun4m machine, no auxio exists. */
56 return;
57 }
58 prom_printf("Cannot find auxio node, cannot continue...\n");
59 prom_halt();
60 #endif
61 }
62 }
63 if(prom_getproperty(auxio_nd, "reg", (char *) auxregs, sizeof(auxregs)) <= 0)
64 return;
65 prom_apply_obio_ranges(auxregs, 0x1);
66 /* Map the register both read and write */
67 r.flags = auxregs[0].which_io & 0xF;
68 r.start = auxregs[0].phys_addr;
69 r.end = auxregs[0].phys_addr + auxregs[0].reg_size - 1;
70 auxio_register = of_ioremap(&r, 0, auxregs[0].reg_size, "auxio");
71 /* Fix the address on sun4m. */
72 if ((((unsigned long) auxregs[0].phys_addr) & 3) == 3)
73 auxio_register += (3 - ((unsigned long)auxio_register & 3));
74
75 set_auxio(AUXIO_LED, 0);
76 }
77
get_auxio(void)78 unsigned char get_auxio(void)
79 {
80 if(auxio_register)
81 return sbus_readb(auxio_register);
82 return 0;
83 }
84 EXPORT_SYMBOL(get_auxio);
85
set_auxio(unsigned char bits_on,unsigned char bits_off)86 void set_auxio(unsigned char bits_on, unsigned char bits_off)
87 {
88 unsigned char regval;
89 unsigned long flags;
90 spin_lock_irqsave(&auxio_lock, flags);
91 switch (sparc_cpu_model) {
92 case sun4m:
93 if(!auxio_register)
94 break; /* VME chassis sun4m, no auxio. */
95 regval = sbus_readb(auxio_register);
96 sbus_writeb(((regval | bits_on) & ~bits_off) | AUXIO_ORMEIN4M,
97 auxio_register);
98 break;
99 case sun4d:
100 break;
101 default:
102 panic("Can't set AUXIO register on this machine.");
103 }
104 spin_unlock_irqrestore(&auxio_lock, flags);
105 }
106 EXPORT_SYMBOL(set_auxio);
107
108 /* sun4m power control register (AUXIO2) */
109
110 volatile u8 __iomem *auxio_power_register = NULL;
111
auxio_power_probe(void)112 void __init auxio_power_probe(void)
113 {
114 struct linux_prom_registers regs;
115 phandle node;
116 struct resource r;
117
118 /* Attempt to find the sun4m power control node. */
119 node = prom_getchild(prom_root_node);
120 node = prom_searchsiblings(node, "obio");
121 node = prom_getchild(node);
122 node = prom_searchsiblings(node, "power");
123 if (node == 0 || (s32)node == -1)
124 return;
125
126 /* Map the power control register. */
127 if (prom_getproperty(node, "reg", (char *)®s, sizeof(regs)) <= 0)
128 return;
129 prom_apply_obio_ranges(®s, 1);
130 memset(&r, 0, sizeof(r));
131 r.flags = regs.which_io & 0xF;
132 r.start = regs.phys_addr;
133 r.end = regs.phys_addr + regs.reg_size - 1;
134 auxio_power_register =
135 (u8 __iomem *)of_ioremap(&r, 0, regs.reg_size, "auxpower");
136
137 /* Display a quick message on the console. */
138 if (auxio_power_register)
139 printk(KERN_INFO "Power off control detected.\n");
140 }
141