diff options
Diffstat (limited to 'arch/sh/mm/pg-dma.c')
| -rw-r--r-- | arch/sh/mm/pg-dma.c | 95 |
1 files changed, 0 insertions, 95 deletions
diff --git a/arch/sh/mm/pg-dma.c b/arch/sh/mm/pg-dma.c deleted file mode 100644 index bb23679369d6..000000000000 --- a/arch/sh/mm/pg-dma.c +++ /dev/null @@ -1,95 +0,0 @@ -/* - * arch/sh/mm/pg-dma.c - * - * Fast clear_page()/copy_page() implementation using the SH DMAC - * - * Copyright (C) 2003 Paul Mundt - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - */ -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <asm/semaphore.h> -#include <asm/mmu_context.h> -#include <asm/addrspace.h> -#include <asm/atomic.h> -#include <asm/page.h> -#include <asm/dma.h> -#include <asm/io.h> - -/* Channel to use for page ops, must be dual-address mode capable. */ -static int dma_channel = CONFIG_DMA_PAGE_OPS_CHANNEL; - -static void copy_page_dma(void *to, void *from) -{ - /* - * This doesn't seem to get triggered until further along in the - * boot process, at which point the DMAC is already initialized. - * Fix this in the same fashion as clear_page_dma() in the event - * that this crashes due to the DMAC not being initialized. - */ - - flush_icache_range((unsigned long)from, PAGE_SIZE); - dma_write_page(dma_channel, (unsigned long)from, (unsigned long)to); - dma_wait_for_completion(dma_channel); -} - -static void clear_page_dma(void *to) -{ - /* - * We get invoked quite early on, if the DMAC hasn't been initialized - * yet, fall back on the slow manual implementation. - */ - if (dma_info[dma_channel].chan != dma_channel) { - clear_page_slow(to); - return; - } - - dma_write_page(dma_channel, (unsigned long)empty_zero_page, - (unsigned long)to); - - /* - * FIXME: Something is a bit racy here, if we poll the counter right - * away, we seem to lock. flushing the page from the dcache doesn't - * seem to make a difference one way or the other, though either a full - * icache or dcache flush does. - * - * The location of this is important as well, and must happen prior to - * the completion loop but after the transfer was initiated. - * - * Oddly enough, this doesn't appear to be an issue for copy_page().. - */ - flush_icache_range((unsigned long)to, PAGE_SIZE); - - dma_wait_for_completion(dma_channel); -} - -static int __init pg_dma_init(void) -{ - int ret; - - ret = request_dma(dma_channel, "page ops"); - if (ret != 0) - return ret; - - copy_page = copy_page_dma; - clear_page = clear_page_dma; - - return ret; -} - -static void __exit pg_dma_exit(void) -{ - free_dma(dma_channel); -} - -module_init(pg_dma_init); -module_exit(pg_dma_exit); - -MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>"); -MODULE_DESCRIPTION("Optimized page copy/clear routines using a dual-address mode capable DMAC channel"); -MODULE_LICENSE("GPL"); - |