xref: /linux/arch/sparc/kernel/auxio_32.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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 
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 
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 
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 
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 *)&regs, sizeof(regs)) <= 0)
127 		return;
128 	prom_apply_obio_ranges(&regs, 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