[PATCH 4/6] MIPS: Loongson: Add DMA support for 7A1000

[Tiezhu Yang]

Implement __phys_to_dma() and __dma_to_phys() according to the
node id offset in 7A1000 DMA route config register.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
 arch/mips/include/asm/mach-loongson64/boot_param.h |  1 +
 arch/mips/loongson64/dma.c                         | 49 +++++++++++++++++++++-
 arch/mips/loongson64/init.c                        | 13 ++++++
 3 files changed, 61 insertions(+), 2 deletions(-)

diff --git a/arch/mips/include/asm/mach-loongson64/boot_param.h b/arch/mips/include/asm/mach-loongson64/boot_param.h
index 225a563..60e7a7e 100644
--- a/arch/mips/include/asm/mach-loongson64/boot_param.h
+++ b/arch/mips/include/asm/mach-loongson64/boot_param.h
@@ -218,5 +218,6 @@ struct loongson_system_configuration {
 extern struct efi_memory_map_loongson *loongson_memmap;
 extern struct loongson_system_configuration loongson_sysconf;
 extern struct board_devices *eboard;
+extern u32 node_id_offset;
 
 #endif
diff --git a/arch/mips/loongson64/dma.c b/arch/mips/loongson64/dma.c
index 5e86635..997c257 100644
--- a/arch/mips/loongson64/dma.c
+++ b/arch/mips/loongson64/dma.c
@@ -2,24 +2,69 @@
 #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)
+struct loongson_dma_ops {
+	dma_addr_t (*phys_to_dma)(struct device *dev, phys_addr_t paddr);
+	phys_addr_t (*dma_to_phys)(struct device *dev, dma_addr_t daddr);
+};
+
+struct loongson_dma_ops loongson_dma;
+
+dma_addr_t __rs780e_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)
+dma_addr_t __ls7a_phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	long nid = (paddr >> 44) & 0x3;
+
+	return ((nid << 44) ^ paddr) | (nid << (36 + node_id_offset));
+}
+
+
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	return loongson_dma.phys_to_dma(dev, paddr);
+}
+
+phys_addr_t __rs780e_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);
 }
 
+phys_addr_t __ls7a_dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+	long nid = (daddr >> (36 + node_id_offset)) & 0x3;
+
+	return ((nid << (36 + node_id_offset)) ^ daddr) | (nid << 44);
+}
+
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+	return loongson_dma.dma_to_phys(dev, daddr);
+}
+
 void __init plat_swiotlb_setup(void)
 {
 	swiotlb_init(1);
+
+	if (strstr(eboard->name, "780E")) {
+		loongson_dma.phys_to_dma = __rs780e_phys_to_dma;
+		loongson_dma.dma_to_phys = __rs780e_dma_to_phys;
+	}
+
+	if (strstr(eboard->name, "7A1000")) {
+		loongson_dma.phys_to_dma = __ls7a_phys_to_dma;
+		loongson_dma.dma_to_phys = __ls7a_dma_to_phys;
+	}
 }
diff --git a/arch/mips/loongson64/init.c b/arch/mips/loongson64/init.c
index 5ac1a0f..dd8463d 100644
--- a/arch/mips/loongson64/init.c
+++ b/arch/mips/loongson64/init.c
@@ -12,6 +12,11 @@
 #include <asm/fw/fw.h>
 
 #include <loongson.h>
+#include <boot_param.h>
+
+#define NODE_ID_OFFSET_ADDR     0x90000E001001041CULL
+
+u32 node_id_offset;
 
 static void __init mips_nmi_setup(void)
 {
@@ -23,6 +28,11 @@ static void __init mips_nmi_setup(void)
 	flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
 }
 
+static void ls7a_early_config(void)
+{
+	node_id_offset = (*(u32 *)NODE_ID_OFFSET_ADDR >> 8) & 0x1F;
+}
+
 void __init prom_init(void)
 {
 	fw_init_cmdline();
@@ -32,6 +42,9 @@ void __init prom_init(void)
 	set_io_port_base((unsigned long)
 		ioremap(LOONGSON_PCIIO_BASE, LOONGSON_PCIIO_SIZE));
 
+	if (strstr(eboard->name, "7A1000"))
+		ls7a_early_config();
+
 	prom_init_numa_memory();
 
 	/* Hardcode to CPU UART 0 */
-- 
2.1.0