| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2020-2022 Loongson Technology Corporation Limited |
| */ |
| #include <linux/init.h> |
| #include <linux/dma-direct.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/dma-map-ops.h> |
| #include <linux/swiotlb.h> |
| |
| #include <asm/bootinfo.h> |
| #include <asm/dma.h> |
| #include <asm/loongson.h> |
| |
| /* |
| * We extract 4bit node id (bit 44~47) from Loongson-3's |
| * 48bit physical address space and embed it into 40bit. |
| */ |
| |
| static int node_id_offset; |
| |
| dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) |
| { |
| long nid = (paddr >> 44) & 0xf; |
| |
| return ((nid << 44) ^ paddr) | (nid << node_id_offset); |
| } |
| |
| phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) |
| { |
| long nid = (daddr >> node_id_offset) & 0xf; |
| |
| return ((nid << node_id_offset) ^ daddr) | (nid << 44); |
| } |
| |
| void __init plat_swiotlb_setup(void) |
| { |
| swiotlb_init(true, SWIOTLB_VERBOSE); |
| node_id_offset = ((readl(LS7A_DMA_CFG) & LS7A_DMA_NODE_MASK) >> LS7A_DMA_NODE_SHF) + 36; |
| } |
