개념 설명 전체 · v6.18.37 / arch/arm64/mm/dma-mapping.c

    1 // SPDX-License-Identifier: GPL-2.0-only
    2 /*
    3  * Copyright (C) 2012 ARM Ltd.
    4  * Author: Catalin Marinas <catalin.marinas@arm.com>
    5  */
    6 
    7 #include <linux/gfp.h>
    8 #include <linux/cache.h>
    9 #include <linux/dma-map-ops.h>
   10 #include <xen/xen.h>
   11 
   12 #include <asm/cacheflush.h>
   13 #include <asm/xen/xen-ops.h>
   14 
   15 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
   16 			      enum dma_data_direction dir)
   17 {
   18 	unsigned long start = (unsigned long)phys_to_virt(paddr);
   19 
   20 	dcache_clean_poc(start, start + size);
   21 }
   22 
   23 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
   24 			   enum dma_data_direction dir)
   25 {
   26 	unsigned long start = (unsigned long)phys_to_virt(paddr);
   27 
   28 	if (dir == DMA_TO_DEVICE)
   29 		return;
   30 
   31 	dcache_inval_poc(start, start + size);
   32 }
   33 
   34 void arch_dma_prep_coherent(struct page *page, size_t size)
   35 {
   36 	unsigned long start = (unsigned long)page_address(page);
   37 
   38 	dcache_clean_poc(start, start + size);
   39 }
   40 
   41 void arch_setup_dma_ops(struct device *dev, bool coherent)
   42 {
   43 	int cls = cache_line_size_of_cpu();
   44 
   45 	WARN_TAINT(!coherent && cls > ARCH_DMA_MINALIGN,
   46 		   TAINT_CPU_OUT_OF_SPEC,
   47 		   "%s %s: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (%d < %d)",
   48 		   dev_driver_string(dev), dev_name(dev),
   49 		   ARCH_DMA_MINALIGN, cls);
   50 
   51 	dev->dma_coherent = coherent;
   52 
   53 	xen_setup_dma_ops(dev);
   54 }