> 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> Thanks for fixing it. Acked-by: Zhou Wang <wangzhou1@xxxxxxxxxxxxx> Best, Zhou > --- > 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 > >
