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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/mips/loongson64/loongson-3/dma.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/loongson64/loongson-3/dma.c')
-rw-r--r--arch/mips/loongson64/loongson-3/dma.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/mips/loongson64/loongson-3/dma.c b/arch/mips/loongson64/loongson-3/dma.c
new file mode 100644
index 000000000..5e86635f7
--- /dev/null
+++ b/arch/mips/loongson64/loongson-3/dma.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/dma-direct.h>
+#include <linux/init.h>
+#include <linux/swiotlb.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 << 37);
+}
+
+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 >> 37) & 0x3;
+ return ((nid << 37) ^ daddr) | (nid << 44);
+}
+
+void __init plat_swiotlb_setup(void)
+{
+ swiotlb_init(1);
+}