diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/frv/mb93090-mb00/pci-dma-nommu.c |
Initial import
Diffstat (limited to 'arch/frv/mb93090-mb00/pci-dma-nommu.c')
-rw-r--r-- | arch/frv/mb93090-mb00/pci-dma-nommu.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/arch/frv/mb93090-mb00/pci-dma-nommu.c b/arch/frv/mb93090-mb00/pci-dma-nommu.c new file mode 100644 index 000000000..b99c2a7cc --- /dev/null +++ b/arch/frv/mb93090-mb00/pci-dma-nommu.c @@ -0,0 +1,146 @@ +/* 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); + +void *dma_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, gfp_t gfp) +{ + 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; +} + +EXPORT_SYMBOL(dma_alloc_coherent); + +void dma_free_coherent(struct device *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle) +{ + 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(); +} + +EXPORT_SYMBOL(dma_free_coherent); + +dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size, + enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); + + frv_cache_wback_inv((unsigned long) ptr, (unsigned long) ptr + size); + + return virt_to_bus(ptr); +} + +EXPORT_SYMBOL(dma_map_single); + +int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction direction) +{ + int i; + + for (i=0; i<nents; i++) + frv_cache_wback_inv(sg_dma_address(&sg[i]), + sg_dma_address(&sg[i]) + sg_dma_len(&sg[i])); + + BUG_ON(direction == DMA_NONE); + + return nents; +} + +EXPORT_SYMBOL(dma_map_sg); + +dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset, + size_t size, enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); + flush_dcache_page(page); + return (dma_addr_t) page_to_phys(page) + offset; +} + +EXPORT_SYMBOL(dma_map_page); |