arch/sparc/kernel/auxio_32.c

   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 }