linux/arch/loongarch/include/asm/mmzone.h
Huacai Chen d4b6f1562a LoongArch: Add Non-Uniform Memory Access (NUMA) support
Add Non-Uniform Memory Access (NUMA) support for LoongArch. LoongArch
has 48-bit physical address, but the HyperTransport I/O bus only support
40-bit address, so we need a custom phys_to_dma() and dma_to_phys() to
extract the 4-bit node id (bit 44~47) from Loongson-3's 48-bit physical
address space and embed it into 40-bit. In the 40-bit dma address, node
id offset can be read from the LS7A_DMA_CFG register.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-06-03 20:09:29 +08:00

19 lines
402 B
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Author: Huacai Chen (chenhuacai@loongson.cn)
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#ifndef _ASM_MMZONE_H_
#define _ASM_MMZONE_H_
#include <asm/page.h>
#include <asm/numa.h>
extern struct pglist_data *node_data[];
#define NODE_DATA(nid) (node_data[(nid)])
extern void setup_zero_pages(void);
#endif /* _ASM_MMZONE_H_ */