| Message ID | 20200415160348.1146-4-pali@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: aardvark: Fix support for Turris MOX and Compex wifi cards | expand |
On Wednesday 15 April 2020 18:03:48 Pali Rohár wrote: > Register PCIE_CORE_CMD_STATUS_REG is applicable only when aardvark > controller is configured for Endpoint mode. Which is not the case of > current kernel driver. > > Signed-off-by: Pali Rohár <pali@kernel.org> > --- > drivers/pci/controller/pci-aardvark.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c > index 6a97a3838098..a1cebc734f2d 100644 > --- a/drivers/pci/controller/pci-aardvark.c > +++ b/drivers/pci/controller/pci-aardvark.c > @@ -423,6 +423,12 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie) > advk_writel(pcie, reg, PCIE_CORE_LINK_CTRL_STAT_REG); > } while (1); > > + /* > + * FIXME: Following code which access PCIE_CORE_CMD_STATUS_REG register > + * is suspicious. This register is applicable only when the PCI > + * controller is configured for Endpoint mode. And not when it > + * is configured for Root Complex. > + */ > reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG); > reg |= PCIE_CORE_CMD_MEM_ACCESS_EN | > PCIE_CORE_CMD_IO_ACCESS_EN | > -- > 2.20.1 > Just to note, above code needs to be removed or fixed or properly commented why is correct and what is doing. I really do not know, so I'm adding at least FIXME comment to document suspicious code which may cause unexpected problems.
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 6a97a3838098..a1cebc734f2d 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -423,6 +423,12 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie) advk_writel(pcie, reg, PCIE_CORE_LINK_CTRL_STAT_REG); } while (1); + /* + * FIXME: Following code which access PCIE_CORE_CMD_STATUS_REG register + * is suspicious. This register is applicable only when the PCI + * controller is configured for Endpoint mode. And not when it + * is configured for Root Complex. + */ reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG); reg |= PCIE_CORE_CMD_MEM_ACCESS_EN | PCIE_CORE_CMD_IO_ACCESS_EN |
Register PCIE_CORE_CMD_STATUS_REG is applicable only when aardvark controller is configured for Endpoint mode. Which is not the case of current kernel driver. Signed-off-by: Pali Rohár <pali@kernel.org> --- drivers/pci/controller/pci-aardvark.c | 6 ++++++ 1 file changed, 6 insertions(+)