From: Marek Behún <kabel@xxxxxxxxxx> commit 95997723b6402cd6c53e0f9e7ac640ec64eaaff8 upstream. The PCIE_MSI_PAYLOAD_REG contains 16-bit MSI number, not only lower 8 bits. Fix reading content of this register and add a comment describing the access to this register. Link: https://lore.kernel.org/r/20211028185659.20329-4-kabel@xxxxxxxxxx Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver") Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> Signed-off-by: Marek Behún <kabel@xxxxxxxxxx> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/controller/pci-aardvark.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -120,6 +120,7 @@ #define PCIE_MSI_STATUS_REG (CONTROL_BASE_ADDR + 0x58) #define PCIE_MSI_MASK_REG (CONTROL_BASE_ADDR + 0x5C) #define PCIE_MSI_PAYLOAD_REG (CONTROL_BASE_ADDR + 0x9C) +#define PCIE_MSI_DATA_MASK GENMASK(15, 0) /* LMI registers base address and register offsets */ #define LMI_BASE_ADDR 0x6000 @@ -1123,8 +1124,12 @@ static void advk_pcie_handle_msi(struct if (!(BIT(msi_idx) & msi_status)) continue; + /* + * msi_idx contains bits [4:0] of the msi_data and msi_data + * contains 16bit MSI interrupt number + */ advk_writel(pcie, BIT(msi_idx), PCIE_MSI_STATUS_REG); - msi_data = advk_readl(pcie, PCIE_MSI_PAYLOAD_REG) & 0xFF; + msi_data = advk_readl(pcie, PCIE_MSI_PAYLOAD_REG) & PCIE_MSI_DATA_MASK; generic_handle_irq(msi_data); }