| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * console.c: Routines that deal with sending and receiving IO |
| 4 | * to/from the current console device using the PROM. |
| 5 | * |
| 6 | * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) |
| 7 | * Copyright (C) 1998 Pete Zaitcev <zaitcev@yahoo.com> |
| 8 | */ |
| 9 | |
| 10 | #include <linux/types.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/sched.h> |
| 13 | #include <asm/openprom.h> |
| 14 | #include <asm/oplib.h> |
| 15 | #include <linux/string.h> |
| 16 | |
| 17 | extern void restore_current(void); |
| 18 | |
| 19 | /* Non blocking put character to console device, returns -1 if |
| 20 | * unsuccessful. |
| 21 | */ |
| 22 | static int prom_nbputchar(const char *buf) |
| 23 | { |
| 24 | unsigned long flags; |
| 25 | int i = -1; |
| 26 | |
| 27 | spin_lock_irqsave(&prom_lock, flags); |
| 28 | switch(prom_vers) { |
| 29 | case PROM_V0: |
| 30 | if ((*(romvec->pv_nbputchar))(*buf)) |
| 31 | i = 1; |
| 32 | break; |
| 33 | case PROM_V2: |
| 34 | case PROM_V3: |
| 35 | if ((*(romvec->pv_v2devops).v2_dev_write)(*romvec->pv_v2bootargs.fd_stdout, |
| 36 | buf, 0x1) == 1) |
| 37 | i = 1; |
| 38 | break; |
| 39 | default: |
| 40 | break; |
| 41 | } |
| 42 | restore_current(); |
| 43 | spin_unlock_irqrestore(&prom_lock, flags); |
| 44 | return i; /* Ugh, we could spin forever on unsupported proms ;( */ |
| 45 | } |
| 46 | |
| 47 | void prom_console_write_buf(const char *buf, int len) |
| 48 | { |
| 49 | while (len) { |
| 50 | int n = prom_nbputchar(buf); |
| 51 | if (n < 0) |
| 52 | continue; |
| 53 | len--; |
| 54 | buf++; |
| 55 | } |
| 56 | } |
| 57 | |