LXR linux/arch/sparc/kernel/auxio

   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 */
  27void __iomem *auxio_register = NULL;
  28static DEFINE_SPINLOCK(auxio_lock);
  29
  30void __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
  78unsigned char get_auxio(void)
  79{
  80        if(auxio_register) 
  81                return sbus_readb(auxio_register);
  82        return 0;
  83}
  84EXPORT_SYMBOL(get_auxio);
  85
  86void 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}
 106EXPORT_SYMBOL(set_auxio);
 107
 108/* sun4m power control register (AUXIO2) */
 109
 110volatile u8 __iomem *auxio_power_register = NULL;
 111
 112void __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