arch/nios2/include/asm/asm-macros.h

Source file repositories/reference/linux-study-clean/arch/nios2/include/asm/asm-macros.h

File Facts

System: Linux kernel
Corpus path: arch/nios2/include/asm/asm-macros.h
Extension: .h
Size: 6375 bytes
Lines: 299
Domain: Architecture Layer
Bucket: arch/nios2
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.

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

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#ifndef _ASM_NIOS2_ASMMACROS_H
#define _ASM_NIOS2_ASMMACROS_H
/*
 * ANDs reg2 with mask and places the result in reg1.
 *
 * You cannnot use the same register for reg1 & reg2.
 */

.macro ANDI32	reg1, reg2, mask
.if \mask & 0xffff
	.if \mask & 0xffff0000
		movhi	\reg1, %hi(\mask)
		movui	\reg1, %lo(\mask)
		and	\reg1, \reg1, \reg2
	.else
		andi	\reg1, \reg2, %lo(\mask)
	.endif
.else
	andhi	\reg1, \reg2, %hi(\mask)
.endif
.endm

/*
 * ORs reg2 with mask and places the result in reg1.
 *
 * It is safe to use the same register for reg1 & reg2.
 */

.macro ORI32	reg1, reg2, mask
.if \mask & 0xffff
	.if \mask & 0xffff0000
		orhi	\reg1, \reg2, %hi(\mask)
		ori	\reg1, \reg2, %lo(\mask)
	.else
		ori	\reg1, \reg2, %lo(\mask)
	.endif
.else
	orhi	\reg1, \reg2, %hi(\mask)
.endif
.endm

/*
 * XORs reg2 with mask and places the result in reg1.
 *
 * It is safe to use the same register for reg1 & reg2.
 */

.macro XORI32	reg1, reg2, mask
.if \mask & 0xffff
	.if \mask & 0xffff0000
		xorhi	\reg1, \reg2, %hi(\mask)
		xori	\reg1, \reg1, %lo(\mask)
	.else
		xori	\reg1, \reg2, %lo(\mask)
	.endif
.else
	xorhi	\reg1, \reg2, %hi(\mask)
.endif
.endm

/*
 * This is a support macro for BTBZ & BTBNZ.  It checks
 * the bit to make sure it is valid 32 value.
 *
 * It is safe to use the same register for reg1 & reg2.
 */

.macro BT	reg1, reg2, bit
.if \bit > 31
	.err
.else
	.if \bit < 16
		andi	\reg1, \reg2, (1 << \bit)
	.else
		andhi	\reg1, \reg2, (1 << (\bit - 16))
	.endif
.endif
.endm

/*
 * Tests the bit in reg2 and branches to label if the
 * bit is zero.  The result of the bit test is stored in reg1.
 *
 * It is safe to use the same register for reg1 & reg2.
 */

.macro BTBZ	reg1, reg2, bit, label
	BT	\reg1, \reg2, \bit
	beq	\reg1, r0, \label
.endm

Annotation

Atlas domain: Architecture Layer / arch/nios2.
Implementation status: source implementation candidate.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.