You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
94 lines
2.3 KiB
94 lines
2.3 KiB
/*
|
|
* arch/xtensa/kernel/pci-dma.c
|
|
*
|
|
* DMA coherent memory allocation.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by the
|
|
* Free Software Foundation; either version 2 of the License, or (at your
|
|
* option) any later version.
|
|
*
|
|
* Copyright (C) 2002 - 2005 Tensilica Inc.
|
|
*
|
|
* Based on version for i386.
|
|
*
|
|
* Chris Zankel <chris@zankel.net>
|
|
* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/string.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/gfp.h>
|
|
#include <asm/io.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
/*
|
|
* Note: We assume that the full memory space is always mapped to 'kseg'
|
|
* Otherwise we have to use page attributes (not implemented).
|
|
*/
|
|
|
|
void *
|
|
dma_alloc_coherent(struct device *dev,size_t size,dma_addr_t *handle,gfp_t flag)
|
|
{
|
|
unsigned long ret;
|
|
unsigned long uncached = 0;
|
|
|
|
/* ignore region speicifiers */
|
|
|
|
flag &= ~(__GFP_DMA | __GFP_HIGHMEM);
|
|
|
|
if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
|
|
flag |= GFP_DMA;
|
|
ret = (unsigned long)__get_free_pages(flag, get_order(size));
|
|
|
|
if (ret == 0)
|
|
return NULL;
|
|
|
|
/* We currently don't support coherent memory outside KSEG */
|
|
|
|
if (ret < XCHAL_KSEG_CACHED_VADDR
|
|
|| ret >= XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_SIZE)
|
|
BUG();
|
|
|
|
|
|
if (ret != 0) {
|
|
memset((void*) ret, 0, size);
|
|
uncached = ret+XCHAL_KSEG_BYPASS_VADDR-XCHAL_KSEG_CACHED_VADDR;
|
|
*handle = virt_to_bus((void*)ret);
|
|
__flush_invalidate_dcache_range(ret, size);
|
|
}
|
|
|
|
return (void*)uncached;
|
|
}
|
|
|
|
void dma_free_coherent(struct device *hwdev, size_t size,
|
|
void *vaddr, dma_addr_t dma_handle)
|
|
{
|
|
long addr=(long)vaddr+XCHAL_KSEG_CACHED_VADDR-XCHAL_KSEG_BYPASS_VADDR;
|
|
|
|
if (addr < 0 || addr >= XCHAL_KSEG_SIZE)
|
|
BUG();
|
|
|
|
free_pages(addr, get_order(size));
|
|
}
|
|
|
|
|
|
void consistent_sync(void *vaddr, size_t size, int direction)
|
|
{
|
|
switch (direction) {
|
|
case PCI_DMA_NONE:
|
|
BUG();
|
|
case PCI_DMA_FROMDEVICE: /* invalidate only */
|
|
__invalidate_dcache_range((unsigned long)vaddr,
|
|
(unsigned long)size);
|
|
break;
|
|
|
|
case PCI_DMA_TODEVICE: /* writeback only */
|
|
case PCI_DMA_BIDIRECTIONAL: /* writeback and invalidate */
|
|
__flush_invalidate_dcache_range((unsigned long)vaddr,
|
|
(unsigned long)size);
|
|
break;
|
|
}
|
|
}
|
|
|