diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 9fd8644a9a4c6..ce4048585da2f 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -18,6 +18,7 @@ config LOONGARCH select ARCH_HAS_KCOV select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE + select ARCH_HAS_PHYS_TO_DMA select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_INLINE_READ_LOCK if !PREEMPTION diff --git a/arch/loongarch/kernel/dma.c b/arch/loongarch/kernel/dma.c index 7a9c6a9dd2d01..cc0ccde58db87 100644 --- a/arch/loongarch/kernel/dma.c +++ b/arch/loongarch/kernel/dma.c @@ -4,6 +4,28 @@ */ #include #include +#include + +/* + * We extract 4bit node id (bit 44~47) from Loongson-3's + * 48bit physical address space and embed it into 40bit. + */ + +static int node_id_offset; + +dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) +{ + long nid = (paddr >> 44) & 0xf; + + return ((nid << 44) ^ paddr) | (nid << node_id_offset); +} + +phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) +{ + long nid = (daddr >> node_id_offset) & 0xf; + + return ((nid << node_id_offset) ^ daddr) | (nid << 44); +} void acpi_arch_dma_setup(struct device *dev) { @@ -11,6 +33,11 @@ void acpi_arch_dma_setup(struct device *dev) u64 mask, end = 0; const struct bus_dma_region *map = NULL; + if (node_id_offset == 0) { + node_id_offset = ((readl(LS7A_DMA_CFG) & LS7A_DMA_NODE_MASK) >> LS7A_DMA_NODE_SHF); + node_id_offset += 36; + } + ret = acpi_dma_get_range(dev, &map); if (!ret && map) { const struct bus_dma_region *r = map;