xref: /linux/arch/sparc/kernel/auxio_32.c (revision cbac924200b838cfb8d8b1415113d788089dc50b)
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 
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 
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 
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 
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 *)&regs, sizeof(regs)) <= 0)
128 		return;
129 	prom_apply_obio_ranges(&regs, 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