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 */
26void __iomem *auxio_register = NULL;
27static DEFINE_SPINLOCK(auxio_lock);
28
29void __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
77unsigned char get_auxio(void)
78{
79	if(auxio_register)
80		return sbus_readb(auxio_register);
81	return 0;
82}
83EXPORT_SYMBOL(get_auxio);
84
85void 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}
105EXPORT_SYMBOL(set_auxio);
106
107/* sun4m power control register (AUXIO2) */
108
109volatile u8 __iomem *auxio_power_register = NULL;
110
111void __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