*参照元 [#ed6d818b] #backlinks *説明 [#r086422f] -パス: [[linux-4.4.1/arch/arm/mm/dma-mapping.c]] -FIXME: これは何? --説明 **引数 [#i6993997] -struct device *dev -- --[[linux-4.4.1/device]] **返り値 [#x61b2152] -u64 -- **参考 [#m92bf5b7] *実装 [#z176e111] static u64 get_coherent_dma_mask(struct device *dev) { u64 mask = (u64)DMA_BIT_MASK(32); - --[[linux-4.4.1/DMA_BIT_MASK()]] if (dev) { mask = dev->coherent_dma_mask; /* * Sanity check the DMA mask - it must be non-zero, and * must be able to be satisfied by a DMA allocation. */ if (mask == 0) { dev_warn(dev, "coherent DMA mask is unset\n"); return 0; } - --[[linux-4.4.1/dev_warn()]] if (!__dma_supported(dev, mask, true)) return 0; - --[[linux-4.4.1/__dma_supported()]] } return mask; } *コメント [#a983b0c1]