On Tue, Dec 31, 2024 at 07:13:33PM +0100, Niklas Cassel wrote: > On Tue, Dec 31, 2024 at 09:21:58PM +0530, Manivannan Sadhasivam wrote: > > On Fri, Dec 20, 2024 at 08:23:29AM +0100, Niklas Cassel wrote: > > > Platforms that do not have (one or more) dedicated IRQs for the eDMA > > > need to set nr_irqs to a non-zero value in their DWC glue driver. > > > > > > Platforms that do have (one or more) dedicated IRQs do not need to > > > initialize nr_irqs. DWC common code will automatically set nr_irqs. > > > > > > Since a glue driver can initialize nr_irqs, dw_pcie_edma_irq_verify() > > > should verify that nr_irqs, if non-zero, is a valid value. Thus, add a > > > check in dw_pcie_edma_irq_verify() to reject a negative nr_irqs value. > > > > > > > Why can't we make dw_edma_chip::nr_irqs unsigned? > > dw_edma is defined in drivers/dma/dw-edma/dw-edma-core.h > in struct dw_edma. > > struct dw_pcie (defined in drivers/pci/controller/dwc/pcie-designware.h) > simply has a struct dw_edma as a struct member. > > If you bounce on nr_irqs in: > drivers/dma/dw-edma/dw-edma-core.c > and in > drivers/dma/dw-edma/dw-edma-pcie.c > you can see that this driver uses signed int for this everywhere. > > I didn't feel like refactoring a whole DMA driver. > There is no need to refactor. Both 'dma' and 'dwc' drivers do not assume that 'nr_irqs' is signed. So simply changing the type to 'unsigned int' is enough. I don't see a valid reason to keep it signed and check for negative value. > > dw_pcie_edma_irq_verify() is supposed to verify that nr_irqs is either > initialized to a valid value by a DWC PCIe glue driver, or that common > code initializes it. > Yes, but the glue drivers do not set negative value explicitly. - Mani -- மணிவண்ணன் சதாசிவம்
