1 files changed, 14 insertions, 0 deletions

diff --git a/arch/mips/loongson/common/dma-swiotlb.c b/arch/mips/loongson/common/dma-swiotlb.c
index c2be01f91575..2c6b989c1bc4 100644
--- a/arch/mips/loongson/common/dma-swiotlb.c
+++ b/arch/mips/loongson/common/dma-swiotlb.c
@@ -105,11 +105,25 @@ static int loongson_dma_set_mask(struct device *dev, u64 mask)
 
 dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
+        long nid;
+#ifdef CONFIG_PHYS48_TO_HT40
+        /* 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 */
+        nid = (paddr >> 44) & 0x3;
+        paddr = ((nid << 44) ^ paddr) | (nid << 37);
+#endif
         return paddr;
 }
 
 phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
+        long nid;
+#ifdef CONFIG_PHYS48_TO_HT40
+        /* 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 */
+        nid = (daddr >> 37) & 0x3;
+        daddr = ((nid << 37) ^ daddr) | (nid << 44);
+#endif
         return daddr;
 }