On Mon, Nov 20, 2023 at 03:40:33PM -0800, Stanislav Kinsburskii wrote: > Explicitly cast __iomem pointer to const void* with __force to fix the > following warning: > > warning: incorrect type in argument 1 (different address spaces) > expected void const volatile *address > got void [noderef] __iomem * I have two questions about this: 1) There's no other use of __force in drivers/pci, so I don't know what's special about pcie-mediatek.c. There should be a way to fix the types so it's not needed. 2) virt_to_phys() is not quite right to begin with because what we want is a *bus* address, not the CPU physical address we get from virt_to_phys(). Obviously the current platforms that use this must not apply any offset between bus and CPU physical addresses, but it's not something we should rely on. There are only three drivers (pci-aardvark.c, pcie-xilinx.c, and this one) that use virt_to_phys(), and they're all slightly wrong here. The *_compose_msi_msg() methods could use a little more consistency across the board. > Signed-off-by: Stanislav Kinsburskii <skinsburskii@xxxxxxxxxxxxxxxxxxx> > --- > drivers/pci/controller/pcie-mediatek.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c > index 66a8f73296fc..27f0f79810a1 100644 > --- a/drivers/pci/controller/pcie-mediatek.c > +++ b/drivers/pci/controller/pcie-mediatek.c > @@ -397,7 +397,7 @@ static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) > phys_addr_t addr; > > /* MT2712/MT7622 only support 32-bit MSI addresses */ > - addr = virt_to_phys(port->base + PCIE_MSI_VECTOR); > + addr = virt_to_phys((__force const void *)port->base + PCIE_MSI_VECTOR); > msg->address_hi = 0; > msg->address_lo = lower_32_bits(addr); > > @@ -520,7 +520,7 @@ static void mtk_pcie_enable_msi(struct mtk_pcie_port *port) > u32 val; > phys_addr_t msg_addr; > > - msg_addr = virt_to_phys(port->base + PCIE_MSI_VECTOR); > + msg_addr = virt_to_phys((__force const void *)port->base + PCIE_MSI_VECTOR); > val = lower_32_bits(msg_addr); > writel(val, port->base + PCIE_IMSI_ADDR); > > > >
