linux/arch/mips/loongson64/dma.c

29 lines
801 B
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/dma-direct.h>
#include <linux/init.h>
#include <linux/swiotlb.h>
#include <boot_param.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 << node_id_offset);
}
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 >> node_id_offset) & 0x3;
return ((nid << node_id_offset) ^ daddr) | (nid << 44);
}
void __init plat_swiotlb_setup(void)
{
swiotlb_init(1);
}