On Fri, Jun 18, 2021 at 05:02:19PM +0100, Jon Hunter wrote: > The cppcheck tool issues the following warning for the Tegra194 PCIe > driver ... > > $ cppcheck --enable=all drivers/pci/controller/dwc/pcie-tegra194.c > Checking drivers/pci/controller/dwc/pcie-tegra194.c ... > > drivers/pci/controller/dwc/pcie-tegra194.c:1829:23: portability: > Shifting signed 32-bit value by 31 bits is > implementation-defined behaviour. See condition at line 1826. > [shiftTooManyBitsSigned] > > appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); > ^ > The above warning occurs because the '1' is treated as a signed type > and so fix this by using the 'BIT' macro to ensure that this is defined > as a unsigned type. The subject and commit log should describe the problem we're fixing. The *warning* is not the problem; the problem is the undefined behavior. I'll fix this up, no need to repost for this. > Fixes: c57247f940e8 PCI: tegra: Add support for PCIe endpoint mode in Tegra194 > Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> > --- > drivers/pci/controller/dwc/pcie-tegra194.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c > index 8fc08336f76e..3c1feeab104f 100644 > --- a/drivers/pci/controller/dwc/pcie-tegra194.c > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c > @@ -1826,7 +1826,7 @@ static int tegra_pcie_ep_raise_msi_irq(struct tegra_pcie_dw *pcie, u16 irq) > if (unlikely(irq > 31)) > return -EINVAL; > > - appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); > + appl_writel(pcie, BIT(irq), APPL_MSI_CTRL_1); > > return 0; > } > -- > 2.25.1 >
