xref: /linux/arch/mips/loongson64/dma.c (revision c94cd9508b1335b949fd13ebd269313c65492df0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/dma-direct.h>
3 #include <linux/init.h>
4 #include <linux/swiotlb.h>
5 #include <asm/bootinfo.h>
6 #include <boot_param.h>
7 
8 dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
9 {
10 	/* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from
11 	 * Loongson-3's 48bit address space and embed it into 40bit */
12 	long nid = (paddr >> 44) & 0x3;
13 
14 	return ((nid << 44) ^ paddr) | (nid << node_id_offset);
15 }
16 
17 phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
18 {
19 	/* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from
20 	 * Loongson-3's 48bit address space and embed it into 40bit */
21 	long nid = (daddr >> node_id_offset) & 0x3;
22 
23 	return ((nid << node_id_offset) ^ daddr) | (nid << 44);
24 }
25 
26 void __init plat_swiotlb_setup(void)
27 {
28 	swiotlb_init(true, SWIOTLB_VERBOSE);
29 }
30