arch/powerpc/math-emu/mtfsfi.c

Source file repositories/reference/linux-study-clean/arch/powerpc/math-emu/mtfsfi.c

File Facts

System
Linux kernel
Corpus path
arch/powerpc/math-emu/mtfsfi.c
Extension
.c
Size
463 bytes
Lines
26
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/uaccess.h>

#include <asm/sfp-machine.h>
#include <math-emu/soft-fp.h>

int
mtfsfi(unsigned int crfD, unsigned int IMM)
{
	u32 mask = 0xf;

	if (!crfD)
		mask = 9;

	__FPU_FPSCR &= ~(mask << ((7 - crfD) << 2));
	__FPU_FPSCR |= (IMM & 0xf) << ((7 - crfD) << 2);

#ifdef DEBUG
	printk("%s: %d %x: %08lx\n", __func__, crfD, IMM, __FPU_FPSCR);
#endif

	return 0;
}

Annotation

Implementation Notes