+++ /dev/null
-/* pci-dma-nommu.c: Dynamic DMA mapping support for the FRV
- *
- * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
- * Written by David Woodhouse (dwmw2@infradead.org)
- *
- * 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.
- */
-
-#include <linux/types.h>
-#include <linux/slab.h>
-#include <linux/export.h>
-#include <linux/dma-mapping.h>
-#include <linux/list.h>
-#include <linux/pci.h>
-#include <asm/io.h>
-
-#if 1
-#define DMA_SRAM_START dma_coherent_mem_start
-#define DMA_SRAM_END dma_coherent_mem_end
-#else // Use video RAM on Matrox
-#define DMA_SRAM_START 0xe8900000
-#define DMA_SRAM_END 0xe8a00000
-#endif
-
-struct dma_alloc_record {
- struct list_head list;
- unsigned long ofs;
- unsigned long len;
-};
-
-static DEFINE_SPINLOCK(dma_alloc_lock);
-static LIST_HEAD(dma_alloc_list);
-
-static void *frv_dma_alloc(struct device *hwdev, size_t size, dma_addr_t *dma_handle,
- gfp_t gfp, unsigned long attrs)
-{
- struct dma_alloc_record *new;
- struct list_head *this = &dma_alloc_list;
- unsigned long flags;
- unsigned long start = DMA_SRAM_START;
- unsigned long end;
-
- if (!DMA_SRAM_START) {
- printk("%s called without any DMA area reserved!\n", __func__);
- return NULL;
- }
-
- new = kmalloc(sizeof (*new), GFP_ATOMIC);
- if (!new)
- return NULL;
-
- /* Round up to a reasonable alignment */
- new->len = (size + 31) & ~31;
-
- spin_lock_irqsave(&dma_alloc_lock, flags);
-
- list_for_each (this, &dma_alloc_list) {
- struct dma_alloc_record *this_r = list_entry(this, struct dma_alloc_record, list);
- end = this_r->ofs;
-
- if (end - start >= size)
- goto gotone;
-
- start = this_r->ofs + this_r->len;
- }
- /* Reached end of list. */
- end = DMA_SRAM_END;
- this = &dma_alloc_list;
-
- if (end - start >= size) {
- gotone:
- new->ofs = start;
- list_add_tail(&new->list, this);
- spin_unlock_irqrestore(&dma_alloc_lock, flags);
-
- *dma_handle = start;
- return (void *)start;
- }
-
- kfree(new);
- spin_unlock_irqrestore(&dma_alloc_lock, flags);
- return NULL;
-}
-
-static void frv_dma_free(struct device *hwdev, size_t size, void *vaddr,
- dma_addr_t dma_handle, unsigned long attrs)
-{
- struct dma_alloc_record *rec;
- unsigned long flags;
-
- spin_lock_irqsave(&dma_alloc_lock, flags);
-
- list_for_each_entry(rec, &dma_alloc_list, list) {
- if (rec->ofs == dma_handle) {
- list_del(&rec->list);
- kfree(rec);
- spin_unlock_irqrestore(&dma_alloc_lock, flags);
- return;
- }
- }
- spin_unlock_irqrestore(&dma_alloc_lock, flags);
- BUG();
-}
-
-static int frv_dma_map_sg(struct device *dev, struct scatterlist *sglist,
- int nents, enum dma_data_direction direction,
- unsigned long attrs)
-{
- struct scatterlist *sg;
- int i;
-
- BUG_ON(direction == DMA_NONE);
-
- if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
- return nents;
-
- for_each_sg(sglist, sg, nents, i) {
- frv_cache_wback_inv(sg_dma_address(sg),
- sg_dma_address(sg) + sg_dma_len(sg));
- }
-
- return nents;
-}
-
-static dma_addr_t frv_dma_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction direction, unsigned long attrs)
-{
- BUG_ON(direction == DMA_NONE);
-
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- flush_dcache_page(page);
-
- return (dma_addr_t) page_to_phys(page) + offset;
-}
-
-static void frv_dma_sync_single_for_device(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction direction)
-{
- flush_write_buffers();
-}
-
-static void frv_dma_sync_sg_for_device(struct device *dev,
- struct scatterlist *sg, int nelems,
- enum dma_data_direction direction)
-{
- flush_write_buffers();
-}
-
-
-static int frv_dma_supported(struct device *dev, u64 mask)
-{
- /*
- * we fall back to GFP_DMA when the mask isn't all 1s,
- * so we can't guarantee allocations that must be
- * within a tighter range than GFP_DMA..
- */
- if (mask < 0x00ffffff)
- return 0;
- return 1;
-}
-
-const struct dma_map_ops frv_dma_ops = {
- .alloc = frv_dma_alloc,
- .free = frv_dma_free,
- .map_page = frv_dma_map_page,
- .map_sg = frv_dma_map_sg,
- .sync_single_for_device = frv_dma_sync_single_for_device,
- .sync_sg_for_device = frv_dma_sync_sg_for_device,
- .dma_supported = frv_dma_supported,
-};
-EXPORT_SYMBOL(frv_dma_ops);
git.samba.org / sfrench / cifs-2.6.git / blobdiff