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f91253a3d0
The Linux kernel will auto-disables all boot consoles whenever it
gets a preferred real console.
Currently on RISC-V systems, if we have a real console which is not
RISCV SBI console then boot consoles (such as earlycon=sbi) are not
auto-disabled when a real console (ttyS0 or ttySIF0) is available.
This results in duplicate prints at boot-time after kernel starts
using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel
parameter was passed by bootloader.
The reason for above issue is that RISCV SBI console always adds
itself as preferred console which is causing other real consoles
to be not used as preferred console.
Ideally "console=" kernel parameter passed by bootloaders should
be the one selecting a preferred real console.
This patch fixes above issue by not forcing RISCV SBI console as
preferred console.
Fixes: afa6b1ccfa ("tty: New RISC-V SBI console driver")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
60 lines
1.1 KiB
C
60 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Copyright (C) 2008 David Gibson, IBM Corporation
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* Copyright (C) 2012 Regents of the University of California
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* Copyright (C) 2017 SiFive
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*/
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#include <linux/console.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/moduleparam.h>
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#include <linux/types.h>
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#include <asm/sbi.h>
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#include "hvc_console.h"
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static int hvc_sbi_tty_put(uint32_t vtermno, const char *buf, int count)
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{
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int i;
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for (i = 0; i < count; i++)
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sbi_console_putchar(buf[i]);
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return i;
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}
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static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
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{
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int i, c;
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for (i = 0; i < count; i++) {
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c = sbi_console_getchar();
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if (c < 0)
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break;
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buf[i] = c;
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}
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return i;
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}
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static const struct hv_ops hvc_sbi_ops = {
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.get_chars = hvc_sbi_tty_get,
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.put_chars = hvc_sbi_tty_put,
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};
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static int __init hvc_sbi_init(void)
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{
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return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
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}
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device_initcall(hvc_sbi_init);
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static int __init hvc_sbi_console_init(void)
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{
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hvc_instantiate(0, 0, &hvc_sbi_ops);
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return 0;
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}
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console_initcall(hvc_sbi_console_init);
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