// SPDX-License-Identifier: GPL-2.0
/*
 * console.c: Routines that deal with sending and receiving IO
 *            to/from the current console device using the PROM.
 *
 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <asm/openprom.h>
#include <asm/oplib.h>
#include <linux/string.h>

/* Non blocking get character from console input device, returns -1
 * if no input was taken.  This can be used for polling.
 */
int
prom_nbgetchar(void)
{
        int i = -1;
        unsigned long flags;

        local_irq_save(flags);
                i = (*(romvec->pv_nbgetchar))();
        local_irq_restore(flags);
        return i; /* Ugh, we could spin forever on unsupported proms ;( */
}

/* Non blocking put character to console device, returns -1 if
 * unsuccessful.
 */
int
prom_nbputchar(char c)
{
        unsigned long flags;
        int i = -1;

        local_irq_save(flags);
                i = (*(romvec->pv_nbputchar))(c);
        local_irq_restore(flags);
        return i; /* Ugh, we could spin forever on unsupported proms ;( */
}

/* Blocking version of get character routine above. */
char
prom_getchar(void)
{
        int character;
        while((character = prom_nbgetchar()) == -1) ;
        return (char) character;
}

/* Blocking version of put character routine above. */
void
prom_putchar(char c)
{
        while(prom_nbputchar(c) == -1) ;
        return;
}

/* Query for input device type */
#if 0
enum prom_input_device
prom_query_input_device()
{
        unsigned long flags;
        int st_p;
        char propb[64];
        char *p;

        switch(prom_vers) {
        case PROM_V0:
        case PROM_V2:
        default:
                switch(*romvec->pv_stdin) {
                case PROMDEV_KBD:       return PROMDEV_IKBD;
                case PROMDEV_TTYA:      return PROMDEV_ITTYA;
                case PROMDEV_TTYB:      return PROMDEV_ITTYB;
                default:
                        return PROMDEV_I_UNK;
                };
        case PROM_V3:
        case PROM_P1275:
                local_irq_save(flags);
                st_p = (*romvec->pv_v2devops.v2_inst2pkg)(*romvec->pv_v2bootargs.fd_stdin);
                __asm__ __volatile__("ld [%0], %%g6\n\t" : :
                                     "r" (&current_set[smp_processor_id()]) :
                                     "memory");
                local_irq_restore(flags);
                if(prom_node_has_property(st_p, "keyboard"))
                        return PROMDEV_IKBD;
                prom_getproperty(st_p, "device_type", propb, sizeof(propb));
                if(strncmp(propb, "serial", sizeof("serial")))
                        return PROMDEV_I_UNK;
                prom_getproperty(prom_root_node, "stdin-path", propb, sizeof(propb));
                p = propb;
                while(*p) p++; p -= 2;
                if(p[0] == ':') {
                        if(p[1] == 'a')
                                return PROMDEV_ITTYA;
                        else if(p[1] == 'b')
                                return PROMDEV_ITTYB;
                }
                return PROMDEV_I_UNK;
        };
}
#endif

/* Query for output device type */

#if 0
enum prom_output_device
prom_query_output_device()
{
        unsigned long flags;
        int st_p;
        char propb[64];
        char *p;
        int propl;

        switch(prom_vers) {
        case PROM_V0:
                switch(*romvec->pv_stdin) {
                case PROMDEV_SCREEN:    return PROMDEV_OSCREEN;
                case PROMDEV_TTYA:      return PROMDEV_OTTYA;
                case PROMDEV_TTYB:      return PROMDEV_OTTYB;
                };
                break;
        case PROM_V2:
        case PROM_V3:
        case PROM_P1275:
                local_irq_save(flags);
                st_p = (*romvec->pv_v2devops.v2_inst2pkg)(*romvec->pv_v2bootargs.fd_stdout);
                __asm__ __volatile__("ld [%0], %%g6\n\t" : :
                                     "r" (&current_set[smp_processor_id()]) :
                                     "memory");
                local_irq_restore(flags);
                propl = prom_getproperty(st_p, "device_type", propb, sizeof(propb));
                if (propl >= 0 && propl == sizeof("display") &&
                        strncmp("display", propb, sizeof("display")) == 0)
                {
                        return PROMDEV_OSCREEN;
                }
                if(prom_vers == PROM_V3) {
                        if(strncmp("serial", propb, sizeof("serial")))
                                return PROMDEV_O_UNK;
                        prom_getproperty(prom_root_node, "stdout-path", propb, sizeof(propb));
                        p = propb;
                        while(*p) p++; p -= 2;
                        if(p[0]==':') {
                                if(p[1] == 'a')
                                        return PROMDEV_OTTYA;
                                else if(p[1] == 'b')
                                        return PROMDEV_OTTYB;
                        }
                        return PROMDEV_O_UNK;
                } else {
                        /* This works on SS-2 (an early OpenFirmware) still. */
                        switch(*romvec->pv_stdin) {
                        case PROMDEV_TTYA:      return PROMDEV_OTTYA;
                        case PROMDEV_TTYB:      return PROMDEV_OTTYB;
                        };
                }
                break;
        };
        return PROMDEV_O_UNK;
}
#endif