arch/mips/bmips/dma.c

Source file repositories/reference/linux-study-clean/arch/mips/bmips/dma.c

File Facts

System
Linux kernel
Corpus path
arch/mips/bmips/dma.c
Extension
.c
Size
626 bytes
Lines
28
Domain
Architecture Layer
Bucket
arch/mips
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/dma-map-ops.h>
#include <asm/bmips.h>
#include <asm/io.h>

bool bmips_rac_flush_disable;

void arch_sync_dma_for_cpu_all(void)
{
	void __iomem *cbr = bmips_cbr_addr;
	u32 cfg;

	if (boot_cpu_type() != CPU_BMIPS3300 &&
	    boot_cpu_type() != CPU_BMIPS4350 &&
	    boot_cpu_type() != CPU_BMIPS4380)
		return;

	if (unlikely(bmips_rac_flush_disable))
		return;

	/* Flush stale data out of the readahead cache */
	cfg = __raw_readl(cbr + BMIPS_RAC_CONFIG);
	__raw_writel(cfg | 0x100, cbr + BMIPS_RAC_CONFIG);
	__raw_readl(cbr + BMIPS_RAC_CONFIG);
}

Annotation

Implementation Notes