arch/sh/mm/cache-sh7705.c

Source file repositories/reference/linux-study-clean/arch/sh/mm/cache-sh7705.c

File Facts

System
Linux kernel
Corpus path
arch/sh/mm/cache-sh7705.c
Extension
.c
Size
5114 bytes
Lines
201
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

if (data == phys) {
				data &= ~(SH_CACHE_VALID | SH_CACHE_UPDATED);
				__raw_writel(data, addr);
			}
		}

		addrstart += current_cpu_data.dcache.way_incr;
	} while (--ways);

	back_to_cached();
	local_irq_restore(flags);
}

/*
 * Write back & invalidate the D-cache of the page.
 * (To avoid "alias" issues)
 */
static void sh7705_flush_dcache_folio(void *arg)
{
	struct folio *folio = arg;
	struct address_space *mapping = folio_flush_mapping(folio);

	if (mapping && !mapping_mapped(mapping))
		clear_bit(PG_dcache_clean, &folio->flags.f);
	else {
		unsigned long pfn = folio_pfn(folio);
		unsigned int i, nr = folio_nr_pages(folio);

		for (i = 0; i < nr; i++)
			__flush_dcache_page((pfn + i) * PAGE_SIZE);
	}
}

static void sh7705_flush_cache_all(void *args)
{
	unsigned long flags;

	local_irq_save(flags);
	jump_to_uncached();

	cache_wback_all();
	back_to_cached();
	local_irq_restore(flags);
}

/*
 * Write back and invalidate I/D-caches for the page.
 *
 * ADDRESS: Virtual Address (U0 address)
 */
static void sh7705_flush_cache_page(void *args)
{
	struct flusher_data *data = args;
	unsigned long pfn = data->addr2;

	__flush_dcache_page(pfn << PAGE_SHIFT);
}

/*
 * This is called when a page-cache page is about to be mapped into a
 * user process' address space.  It offers an opportunity for a
 * port to ensure d-cache/i-cache coherency if necessary.
 *
 * Not entirely sure why this is necessary on SH3 with 32K cache but
 * without it we get occasional "Memory fault" when loading a program.
 */
static void sh7705_flush_icache_folio(void *arg)
{
	struct folio *folio = arg;
	__flush_purge_region(folio_address(folio), folio_size(folio));
}

void __init sh7705_cache_init(void)
{
	local_flush_icache_range	= sh7705_flush_icache_range;
	local_flush_dcache_folio	= sh7705_flush_dcache_folio;
	local_flush_cache_all		= sh7705_flush_cache_all;
	local_flush_cache_mm		= sh7705_flush_cache_all;
	local_flush_cache_dup_mm	= sh7705_flush_cache_all;
	local_flush_cache_range		= sh7705_flush_cache_all;
	local_flush_cache_page		= sh7705_flush_cache_page;
	local_flush_icache_folio	= sh7705_flush_icache_folio;
}

Annotation

Implementation Notes