arch/sh/mm/cache-sh3.c

Source file repositories/reference/linux-study-clean/arch/sh/mm/cache-sh3.c

File Facts

System
Linux kernel
Corpus path
arch/sh/mm/cache-sh3.c
Extension
.c
Size
2552 bytes
Lines
103
Domain
Architecture Layer
Bucket
arch/sh
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-only
/*
 * arch/sh/mm/cache-sh3.c
 *
 * Copyright (C) 1999, 2000  Niibe Yutaka
 * Copyright (C) 2002 Paul Mundt
 */

#include <linux/init.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/threads.h>
#include <asm/addrspace.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/io.h>
#include <linux/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>

/*
 * Write back the dirty D-caches, but not invalidate them.
 *
 * Is this really worth it, or should we just alias this routine
 * to __flush_purge_region too?
 *
 * START: Virtual Address (U0, P1, or P3)
 * SIZE: Size of the region.
 */

static void sh3__flush_wback_region(void *start, int size)
{
	unsigned long v, j;
	unsigned long begin, end;
	unsigned long flags;

	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
		& ~(L1_CACHE_BYTES-1);

	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
		unsigned long addrstart = CACHE_OC_ADDRESS_ARRAY;
		for (j = 0; j < current_cpu_data.dcache.ways; j++) {
			unsigned long data, addr, p;

			p = __pa(v);
			addr = addrstart | (v & current_cpu_data.dcache.entry_mask);
			local_irq_save(flags);
			data = __raw_readl(addr);

			if ((data & CACHE_PHYSADDR_MASK) ==
			    (p & CACHE_PHYSADDR_MASK)) {
				data &= ~SH_CACHE_UPDATED;
				__raw_writel(data, addr);
				local_irq_restore(flags);
				break;
			}
			local_irq_restore(flags);
			addrstart += current_cpu_data.dcache.way_incr;
		}
	}
}

/*
 * Write back the dirty D-caches and invalidate them.
 *
 * START: Virtual Address (U0, P1, or P3)
 * SIZE: Size of the region.
 */
static void sh3__flush_purge_region(void *start, int size)
{
	unsigned long v;
	unsigned long begin, end;

	begin = (unsigned long)start & ~(L1_CACHE_BYTES-1);
	end = ((unsigned long)start + size + L1_CACHE_BYTES-1)
		& ~(L1_CACHE_BYTES-1);

	for (v = begin; v < end; v+=L1_CACHE_BYTES) {
		unsigned long data, addr;

		data = (v & 0xfffffc00); /* _Virtual_ address, ~U, ~V */
		addr = CACHE_OC_ADDRESS_ARRAY |
			(v & current_cpu_data.dcache.entry_mask) | SH_CACHE_ASSOC;
		__raw_writel(data, addr);
	}
}

void __init sh3_cache_init(void)

Annotation

Implementation Notes