// SPDX-License-Identifier: GPL-2.0 #include <linux/dma-direct.h> #include <linux/init.h> #include <linux/swiotlb.h> dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr) { /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from * Loongson-3's 48bit address space and embed it into 40bit */ long nid = (paddr >> 44) & 0x3; return ((nid << 44) ^ paddr) | (nid << 37); } phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr) { /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from * Loongson-3's 48bit address space and embed it into 40bit */ long nid = (daddr >> 37) & 0x3; return ((nid << 37) ^ daddr) | (nid << 44); } void __init plat_swiotlb_setup(void) { swiotlb_init(1); }