71 lines
1.9 KiB
C
71 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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// Copyright (C) 2022 Linutronix GmbH, John Ogness
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// Copyright (C) 2022 Intel, Thomas Gleixner
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#include <linux/kernel.h>
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#include <linux/console.h>
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#include "internal.h"
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/*
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* Printk console printing implementation for consoles which does not depend
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* on the legacy style console_lock mechanism.
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*/
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/**
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* nbcon_state_set - Helper function to set the console state
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* @con: Console to update
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* @new: The new state to write
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*
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* Only to be used when the console is not yet or no longer visible in the
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* system. Otherwise use nbcon_state_try_cmpxchg().
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*/
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static inline void nbcon_state_set(struct console *con, struct nbcon_state *new)
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{
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atomic_set(&ACCESS_PRIVATE(con, nbcon_state), new->atom);
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}
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/**
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* nbcon_state_read - Helper function to read the console state
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* @con: Console to read
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* @state: The state to store the result
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*/
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static inline void nbcon_state_read(struct console *con, struct nbcon_state *state)
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{
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state->atom = atomic_read(&ACCESS_PRIVATE(con, nbcon_state));
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}
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/**
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* nbcon_state_try_cmpxchg() - Helper function for atomic_try_cmpxchg() on console state
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* @con: Console to update
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* @cur: Old/expected state
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* @new: New state
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*
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* Return: True on success. False on fail and @cur is updated.
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*/
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static inline bool nbcon_state_try_cmpxchg(struct console *con, struct nbcon_state *cur,
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struct nbcon_state *new)
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{
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return atomic_try_cmpxchg(&ACCESS_PRIVATE(con, nbcon_state), &cur->atom, new->atom);
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}
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/**
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* nbcon_init - Initialize the nbcon console specific data
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* @con: Console to initialize
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*/
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void nbcon_init(struct console *con)
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{
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struct nbcon_state state = { };
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nbcon_state_set(con, &state);
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}
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/**
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* nbcon_cleanup - Cleanup the nbcon console specific data
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* @con: Console to cleanup
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*/
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void nbcon_cleanup(struct console *con)
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{
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struct nbcon_state state = { };
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nbcon_state_set(con, &state);
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}
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