On 2015/9/16 10:17, Rob Herring wrote: > On 09/15/2015 08:14 PM, Zhou Wang wrote: >> On 2015/9/16 3:43, Rob Herring wrote: >>> On 09/15/2015 07:49 AM, Zhou Wang wrote: >>>> This patch adds related DTS binding document for HiSilicon PCIe host driver. >>>> >>>> Signed-off-by: Zhou Wang <wangzhou1@xxxxxxxxxxxxx> >>>> --- >>>> .../devicetree/bindings/pci/hisilicon-pcie.txt | 46 ++++++++++++++++++++++ >>>> 1 file changed, 46 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/pci/hisilicon-pcie.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/pci/hisilicon-pcie.txt b/Documentation/devicetree/bindings/pci/hisilicon-pcie.txt >>>> new file mode 100644 >>>> index 0000000..2afc9d1 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/pci/hisilicon-pcie.txt >>>> @@ -0,0 +1,46 @@ >>>> +HiSilicon PCIe host bridge DT description >>>> + >>>> +HiSilicon PCIe host controller is based on Designware PCI core. >>>> +It shares common functions with PCIe Designware core driver and inherits >>>> +common properties defined in >>>> +Documentation/devicetree/bindings/pci/designware-pci.txt. >>>> + >>>> +Additional properties are described here: >>>> + >>>> +Required properties: >>>> +- compatible: Should contain "hisilicon,hip05-pcie". >>>> +- reg: Should contain rc_dbi, subctrl, config registers location and length. >>>> +- reg-names: Must include the following entries: >>>> + "rc_dbi": controller configuration registers; >>>> + "subctrl": whole PCIe hosts configuration registers; >>>> + "config": PCIe configuration space registers. >>>> +- msi-parent: Should be its_pcie which is an ITS receiving MSI interrupts. >>>> +- port-id: Should be 0, 1, 2 or 3. >>> >>> What is port-id for? Use of instance indexes need to have good reason. >>> >>> Rob >> >> There are four PCIe controllers in HiSilicon Hip05 SoC, port-id just indicates >> which one we use. And we will use port-id to locate related registers in driver. > > Just having multiple instances is not a reason. So looking at the > driver, port-id is used to calculate register addresses for these registers: > > #define PCIE_SUBCTRL_MODE_REG 0x2800 > #define PCIE_SUBCTRL_SYS_STATE4_REG 0x6818 > > Is the base address of subctrl the same on all 4 ports? If so, you Yes, same subctrl address for 4 ports. Will use syscon to access subctrl registers in next version. Many thanks for pointing this, Zhou > should not have overlapping resources in the DT. Either split these 2 > registers into 2 reg regions (for each register) or use syscon to > provide access to the region. > > Rob > > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
