1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/dma-direct.h> 3 #include <linux/init.h> 4 #include <linux/swiotlb.h> 5 6 dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr) 7 { 8 /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from 9 * Loongson-3's 48bit address space and embed it into 40bit */ 10 long nid = (paddr >> 44) & 0x3; 11 return ((nid << 44) ^ paddr) | (nid << 37); 12 } 13 14 phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr) 15 { 16 /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from 17 * Loongson-3's 48bit address space and embed it into 40bit */ 18 long nid = (daddr >> 37) & 0x3; 19 return ((nid << 37) ^ daddr) | (nid << 44); 20 } 21 22 void __init plat_swiotlb_setup(void) 23 { 24 swiotlb_init(1); 25 } 26