diff options
| -rw-r--r-- | arch/hexagon/include/asm/dma-mapping.h | 101 | ||||
| -rw-r--r-- | arch/hexagon/include/asm/dma.h | 29 | ||||
| -rw-r--r-- | arch/hexagon/kernel/dma.c | 220 |
3 files changed, 350 insertions, 0 deletions
diff --git a/arch/hexagon/include/asm/dma-mapping.h b/arch/hexagon/include/asm/dma-mapping.h new file mode 100644 index 000000000000..448b224ba4ef --- /dev/null +++ b/arch/hexagon/include/asm/dma-mapping.h @@ -0,0 +1,101 @@ +/* + * DMA operations for the Hexagon architecture + * + * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#ifndef _ASM_DMA_MAPPING_H +#define _ASM_DMA_MAPPING_H + +#include <linux/types.h> +#include <linux/cache.h> +#include <linux/mm.h> +#include <linux/scatterlist.h> +#include <linux/dma-mapping.h> +#include <linux/dma-debug.h> +#include <linux/dma-attrs.h> +#include <asm/io.h> + +struct device; +extern int bad_dma_address; + +extern struct dma_map_ops *dma_ops; + +#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f) +#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h) + +static inline struct dma_map_ops *get_dma_ops(struct device *dev) +{ + if (unlikely(dev == NULL)) + return NULL; + + return dma_ops; +} + +extern int dma_supported(struct device *dev, u64 mask); +extern int dma_set_mask(struct device *dev, u64 mask); +extern int dma_is_consistent(struct device *dev, dma_addr_t dma_handle); +extern void dma_cache_sync(struct device *dev, void *vaddr, size_t size, + enum dma_data_direction direction); + +#include <asm-generic/dma-mapping-common.h> + +static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) +{ + if (!dev->dma_mask) + return 0; + return addr + size - 1 <= *dev->dma_mask; +} + +static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + struct dma_map_ops *dma_ops = get_dma_ops(dev); + + if (dma_ops->mapping_error) + return dma_ops->mapping_error(dev, dma_addr); + + return (dma_addr == bad_dma_address); +} + +static inline void *dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag) +{ + void *ret; + struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!dma_ops); + + ret = ops->alloc_coherent(dev, size, dma_handle, flag); + + debug_dma_alloc_coherent(dev, size, *dma_handle, ret); + + return ret; +} + +static inline void dma_free_coherent(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t dma_handle) +{ + struct dma_map_ops *dma_ops = get_dma_ops(dev); + + BUG_ON(!dma_ops); + + dma_ops->free_coherent(dev, size, cpu_addr, dma_handle); + + debug_dma_free_coherent(dev, size, cpu_addr, dma_handle); +} + +#endif diff --git a/arch/hexagon/include/asm/dma.h b/arch/hexagon/include/asm/dma.h new file mode 100644 index 000000000000..da6d2f61a93a --- /dev/null +++ b/arch/hexagon/include/asm/dma.h @@ -0,0 +1,29 @@ +/* + * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#ifndef _ASM_DMA_H +#define _ASM_DMA_H + +#include <asm/io.h> + +#define MAX_DMA_CHANNELS 1 +#define MAX_DMA_ADDRESS (PAGE_OFFSET) + +extern size_t hexagon_coherent_pool_size; + +#endif diff --git a/arch/hexagon/kernel/dma.c b/arch/hexagon/kernel/dma.c new file mode 100644 index 000000000000..e711ace62fdf --- /dev/null +++ b/arch/hexagon/kernel/dma.c @@ -0,0 +1,220 @@ +/* + * DMA implementation for Hexagon + * + * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#include <linux/dma-mapping.h> +#include <linux/bootmem.h> +#include <linux/genalloc.h> +#include <asm/dma-mapping.h> + +struct dma_map_ops *dma_ops; +EXPORT_SYMBOL(dma_ops); + +int bad_dma_address; /* globals are automatically initialized to zero */ + +int dma_supported(struct device *dev, u64 mask) +{ + if (mask == DMA_BIT_MASK(32)) + return 1; + else + return 0; +} +EXPORT_SYMBOL(dma_supported); + +int dma_set_mask(struct device *dev, u64 mask) +{ + if (!dev->dma_mask || !dma_supported(dev, mask)) + return -EIO; + + *dev->dma_mask = mask; + + return 0; +} +EXPORT_SYMBOL(dma_set_mask); + +static struct gen_pool *coherent_pool; + + +/* Allocates from a pool of uncached memory that was reserved at boot time */ + +void *hexagon_dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_addr, gfp_t flag) +{ + void *ret; + + if (coherent_pool == NULL) { + coherent_pool = gen_pool_create(PAGE_SHIFT, -1); + + if (coherent_pool == NULL) + panic("Can't create %s() memory pool!", __func__); + else + gen_pool_add(coherent_pool, + (PAGE_OFFSET + (max_low_pfn << PAGE_SHIFT)), + hexagon_coherent_pool_size, -1); + } + + ret = (void *) gen_pool_alloc(coherent_pool, size); + + if (ret) { + memset(ret, 0, size); + *dma_addr = (dma_addr_t) (ret - PAGE_OFFSET); + } else + *dma_addr = ~0; + + return ret; +} + +static void hexagon_free_coherent(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_addr) +{ + gen_pool_free(coherent_pool, (unsigned long) vaddr, size); +} + +static int check_addr(const char *name, struct device *hwdev, + dma_addr_t bus, size_t size) +{ + if (hwdev && hwdev->dma_mask && !dma_capable(hwdev, bus, size)) { + if (*hwdev->dma_mask >= DMA_BIT_MASK(32)) + printk(KERN_ERR + "%s: overflow %Lx+%zu of device mask %Lx\n", + name, (long long)bus, size, + (long long)*hwdev->dma_mask); + return 0; + } + return 1; +} + +static int hexagon_map_sg(struct device *hwdev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + struct scatterlist *s; + int i; + + WARN_ON(nents == 0 || sg[0].length == 0); + + for_each_sg(sg, s, nents, i) { + s->dma_address = sg_phys(s); + if (!check_addr("map_sg", hwdev, s->dma_address, s->length)) + return 0; + + s->dma_length = s->length; + + flush_dcache_range(PAGE_OFFSET + s->dma_address, + PAGE_OFFSET + s->dma_address + s->length); + } + + return nents; +} + +/* + * address is virtual + */ +static inline void dma_sync(void *addr, size_t size, + enum dma_data_direction dir) +{ + switch (dir) { + case DMA_TO_DEVICE: + hexagon_clean_dcache_range((unsigned long) addr, + (unsigned long) addr + size); + break; + case DMA_FROM_DEVICE: + hexagon_inv_dcache_range((unsigned long) addr, + (unsigned long) addr + size); + break; + case DMA_BIDIRECTIONAL: + flush_dcache_range((unsigned long) addr, + (unsigned long) addr + size); + break; + default: + BUG(); + } +} + +static inline void *dma_addr_to_virt(dma_addr_t dma_addr) +{ + return phys_to_virt((unsigned long) dma_addr); +} + +/** + * hexagon_map_page() - maps an address for device DMA + * @dev: pointer to DMA device + * @page: pointer to page struct of DMA memory + * @offset: offset within page + * @size: size of memory to map + * @dir: transfer direction + * @attrs: pointer to DMA attrs (not used) + * + * Called to map a memory address to a DMA address prior + * to accesses to/from device. + * + * We don't particularly have many hoops to jump through + * so far. Straight translation between phys and virtual. + * + * DMA is not cache coherent so sync is necessary; this + * seems to be a convenient place to do it. + * + */ +static dma_addr_t hexagon_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + dma_addr_t bus = page_to_phys(page) + offset; + WARN_ON(size == 0); + + if (!check_addr("map_single", dev, bus, size)) + return bad_dma_address; + + dma_sync(dma_addr_to_virt(bus), size, dir); + + return bus; +} + +static void hexagon_sync_single_for_cpu(struct device *dev, + dma_addr_t dma_handle, size_t size, + enum dma_data_direction dir) +{ + dma_sync(dma_addr_to_virt(dma_handle), size, dir); +} + +static void hexagon_sync_single_for_device(struct device *dev, + dma_addr_t dma_handle, size_t size, + enum dma_data_direction dir) +{ + dma_sync(dma_addr_to_virt(dma_handle), size, dir); +} + +struct dma_map_ops hexagon_dma_ops = { + .alloc_coherent = hexagon_dma_alloc_coherent, + .free_coherent = hexagon_free_coherent, + .map_sg = hexagon_map_sg, + .map_page = hexagon_map_page, + .sync_single_for_cpu = hexagon_sync_single_for_cpu, + .sync_single_for_device = hexagon_sync_single_for_device, + .is_phys = 1, +}; + +void __init hexagon_dma_init(void) +{ + if (dma_ops) + return; + + dma_ops = &hexagon_dma_ops; +} |