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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ALPHA_FPU_H
#define __ASM_ALPHA_FPU_H
#include <asm/special_insns.h>
#include <uapi/asm/fpu.h>
/* The following two functions don't need trapb/excb instructions
around the mf_fpcr/mt_fpcr instructions because (a) the kernel
never generates arithmetic faults and (b) call_pal instructions
are implied trap barriers. */
static inline unsigned long
rdfpcr(void)
{
unsigned long tmp, ret;
preempt_disable();
if (current_thread_info()->status & TS_SAVED_FP) {
ret = current_thread_info()->fp[31];
} else {
#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
__asm__ __volatile__ (
"ftoit $f0,%0\n\t"
"mf_fpcr $f0\n\t"
"ftoit $f0,%1\n\t"
"itoft %0,$f0"
: "=r"(tmp), "=r"(ret));
#else
__asm__ __volatile__ (
"stt $f0,%0\n\t"
"mf_fpcr $f0\n\t"
"stt $f0,%1\n\t"
"ldt $f0,%0"
: "=m"(tmp), "=m"(ret));
#endif
}
preempt_enable();
return ret;
}
static inline void
wrfpcr(unsigned long val)
{
unsigned long tmp;
preempt_disable();
if (current_thread_info()->status & TS_SAVED_FP) {
current_thread_info()->status |= TS_RESTORE_FP;
current_thread_info()->fp[31] = val;
} else {
#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
__asm__ __volatile__ (
"ftoit $f0,%0\n\t"
"itoft %1,$f0\n\t"
"mt_fpcr $f0\n\t"
"itoft %0,$f0"
: "=&r"(tmp) : "r"(val));
#else
__asm__ __volatile__ (
"stt $f0,%0\n\t"
"ldt $f0,%1\n\t"
"mt_fpcr $f0\n\t"
"ldt $f0,%0"
: "=m"(tmp) : "m"(val));
#endif
}
preempt_enable();
}
static inline unsigned long
swcr_update_status(unsigned long swcr, unsigned long fpcr)
{
/* EV6 implements most of the bits in hardware. Collect
the acrued exception bits from the real fpcr. */
if (implver() == IMPLVER_EV6) {
swcr &= ~IEEE_STATUS_MASK;
swcr |= (fpcr >> 35) & IEEE_STATUS_MASK;
}
return swcr;
}
extern unsigned long alpha_read_fp_reg (unsigned long reg);
extern void alpha_write_fp_reg (unsigned long reg, unsigned long val);
extern unsigned long alpha_read_fp_reg_s (unsigned long reg);
extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val);
#endif /* __ASM_ALPHA_FPU_H */
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