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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 1999, 2023
*/
#include <linux/spinlock.h>
#include <linux/smp.h>
#include <asm/abs_lowcore.h>
#include <asm/ctlreg.h>
/*
* ctl_lock guards access to global control register contents which
* are kept in the control register save area within absolute lowcore
* at physical address zero.
*/
static DEFINE_SPINLOCK(system_ctl_lock);
void system_ctlreg_lock(void)
__acquires(&system_ctl_lock)
{
spin_lock(&system_ctl_lock);
}
void system_ctlreg_unlock(void)
__releases(&system_ctl_lock)
{
spin_unlock(&system_ctl_lock);
}
struct ctl_bit_parms {
unsigned long orval;
unsigned long andval;
int cr;
};
static void ctl_bit_callback(void *info)
{
struct ctl_bit_parms *pp = info;
unsigned long regs[16];
__local_ctl_store(regs, 0, 15);
regs[pp->cr] &= pp->andval;
regs[pp->cr] |= pp->orval;
__local_ctl_load(regs, 0, 15);
}
void system_ctl_set_clear_bit(unsigned int cr, unsigned int bit, bool set)
{
struct ctl_bit_parms pp = { .cr = cr, };
struct lowcore *abs_lc;
pp.orval = set ? 1UL << bit : 0;
pp.andval = set ? -1UL : ~(1UL << bit);
system_ctlreg_lock();
abs_lc = get_abs_lowcore();
abs_lc->cregs_save_area[cr] &= pp.andval;
abs_lc->cregs_save_area[cr] |= pp.orval;
put_abs_lowcore(abs_lc);
on_each_cpu(ctl_bit_callback, &pp, 1);
system_ctlreg_unlock();
}
EXPORT_SYMBOL(system_ctl_set_clear_bit);
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