From 5f97f7f9400de47ae837170bb274e90ad3934386 Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Mon, 25 Sep 2006 23:32:13 -0700 Subject: [PATCH] avr32 architecture This adds support for the Atmel AVR32 architecture as well as the AT32AP7000 CPU and the AT32STK1000 development board. AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for cost-sensitive embedded applications, with particular emphasis on low power consumption and high code density. The AVR32 architecture is not binary compatible with earlier 8-bit AVR architectures. The AVR32 architecture, including the instruction set, is described by the AVR32 Architecture Manual, available from http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture. It features a 7-stage pipeline, 16KB instruction and data caches and a full Memory Management Unit. It also comes with a large set of integrated peripherals, many of which are shared with the AT91 ARM-based controllers from Atmel. Full data sheet is available from http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf while the CPU core implementation including caches and MMU is documented by the AVR32 AP Technical Reference, available from http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf Information about the AT32STK1000 development board can be found at http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918 including a BSP CD image with an earlier version of this patch, development tools (binaries and source/patches) and a root filesystem image suitable for booting from SD card. Alternatively, there's a preliminary "getting started" guide available at http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links to the sources and patches you will need in order to set up a cross-compiling environment for avr32-linux. This patch, as well as the other patches included with the BSP and the toolchain patches, is actively supported by Atmel Corporation. [dmccr@us.ibm.com: Fix more pxx_page macro locations] [bunk@stusta.de: fix `make defconfig'] Signed-off-by: Haavard Skinnemoen Signed-off-by: Adrian Bunk Signed-off-by: Dave McCracken Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/avr32/mm/dma-coherent.c | 139 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 arch/avr32/mm/dma-coherent.c (limited to 'arch/avr32/mm/dma-coherent.c') diff --git a/arch/avr32/mm/dma-coherent.c b/arch/avr32/mm/dma-coherent.c new file mode 100644 index 000000000000..44ab8a7bdae2 --- /dev/null +++ b/arch/avr32/mm/dma-coherent.c @@ -0,0 +1,139 @@ +/* + * Copyright (C) 2004-2006 Atmel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include + +#include +#include + +void dma_cache_sync(void *vaddr, size_t size, int direction) +{ + /* + * No need to sync an uncached area + */ + if (PXSEG(vaddr) == P2SEG) + return; + + switch (direction) { + case DMA_FROM_DEVICE: /* invalidate only */ + dma_cache_inv(vaddr, size); + break; + case DMA_TO_DEVICE: /* writeback only */ + dma_cache_wback(vaddr, size); + break; + case DMA_BIDIRECTIONAL: /* writeback and invalidate */ + dma_cache_wback_inv(vaddr, size); + break; + default: + BUG(); + } +} +EXPORT_SYMBOL(dma_cache_sync); + +static struct page *__dma_alloc(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp) +{ + struct page *page, *free, *end; + int order; + + size = PAGE_ALIGN(size); + order = get_order(size); + + page = alloc_pages(gfp, order); + if (!page) + return NULL; + split_page(page, order); + + /* + * When accessing physical memory with valid cache data, we + * get a cache hit even if the virtual memory region is marked + * as uncached. + * + * Since the memory is newly allocated, there is no point in + * doing a writeback. If the previous owner cares, he should + * have flushed the cache before releasing the memory. + */ + invalidate_dcache_region(phys_to_virt(page_to_phys(page)), size); + + *handle = page_to_bus(page); + free = page + (size >> PAGE_SHIFT); + end = page + (1 << order); + + /* + * Free any unused pages + */ + while (free < end) { + __free_page(free); + free++; + } + + return page; +} + +static void __dma_free(struct device *dev, size_t size, + struct page *page, dma_addr_t handle) +{ + struct page *end = page + (PAGE_ALIGN(size) >> PAGE_SHIFT); + + while (page < end) + __free_page(page++); +} + +void *dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp) +{ + struct page *page; + void *ret = NULL; + + page = __dma_alloc(dev, size, handle, gfp); + if (page) + ret = phys_to_uncached(page_to_phys(page)); + + return ret; +} +EXPORT_SYMBOL(dma_alloc_coherent); + +void dma_free_coherent(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t handle) +{ + void *addr = phys_to_cached(uncached_to_phys(cpu_addr)); + struct page *page; + + pr_debug("dma_free_coherent addr %p (phys %08lx) size %u\n", + cpu_addr, (unsigned long)handle, (unsigned)size); + BUG_ON(!virt_addr_valid(addr)); + page = virt_to_page(addr); + __dma_free(dev, size, page, handle); +} +EXPORT_SYMBOL(dma_free_coherent); + +#if 0 +void *dma_alloc_writecombine(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp) +{ + struct page *page; + + page = __dma_alloc(dev, size, handle, gfp); + + /* Now, map the page into P3 with write-combining turned on */ + return __ioremap(page_to_phys(page), size, _PAGE_BUFFER); +} +EXPORT_SYMBOL(dma_alloc_writecombine); + +void dma_free_writecombine(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t handle) +{ + struct page *page; + + iounmap(cpu_addr); + + page = bus_to_page(handle); + __dma_free(dev, size, page, handle); +} +EXPORT_SYMBOL(dma_free_writecombine); +#endif -- cgit v1.2.3