linux/arch/mips/loongson64/dma.c
Christoph Hellwig 5ceda74093 dma-direct: rename and cleanup __phys_to_dma
The __phys_to_dma vs phys_to_dma distinction isn't exactly obvious.  Try
to improve the situation by renaming __phys_to_dma to
phys_to_dma_unencryped, and not forcing architectures that want to
override phys_to_dma to actually provide __phys_to_dma.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-11 09:14:43 +02:00

29 lines
797 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);
}