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/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 }