Remove the loaded hisi_dma driver and reload it, the driver fails to work properly. The following error is reported in the kernel log: [ 1475.597609] hisi_dma 0000:7b:00.0: Failed to allocate MSI vectors! [ 1475.604915] hisi_dma: probe of 0000:7b:00.0 failed with error -28 As noted in "The MSI Driver Guide HOWTO"[1], the number of MSI interrupt must be a power of two. The Kunpeng DMA driver allocates 30 MSI interrupts. As a result, no space left on device is reported when the driver is reloaded and allocates interrupt vectors from the interrupt domain. This patch changes the number of interrupt vectors allocated by hisi_dma driver to 32 to avoid this problem. [1] https://www.kernel.org/doc/html/latest/PCI/msi-howto.html Fixes: e9f08b65250d ("dmaengine: hisilicon: Add Kunpeng DMA engine support") Signed-off-by: Jie Hai <haijie1@xxxxxxxxxx> --- drivers/dma/hisi_dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/hisi_dma.c b/drivers/dma/hisi_dma.c index 97c87a7cba87..43817ced3a3e 100644 --- a/drivers/dma/hisi_dma.c +++ b/drivers/dma/hisi_dma.c @@ -30,7 +30,7 @@ #define HISI_DMA_MODE 0x217c #define HISI_DMA_OFFSET 0x100 -#define HISI_DMA_MSI_NUM 30 +#define HISI_DMA_MSI_NUM 32 #define HISI_DMA_CHAN_NUM 30 #define HISI_DMA_Q_DEPTH_VAL 1024 -- 2.33.0
