Re: [PATCH v3 10/11] dt-bindings: imx6q-pcie: Add i.MX8Q pcie compatible string

From: Frank Li
Date: Mon Apr 29 2024 - 17:23:51 EST


On Mon, Apr 29, 2024 at 10:48:23AM -0500, Rob Herring wrote:
> On Tue, Apr 02, 2024 at 10:33:46AM -0400, Frank Li wrote:
> > From: Richard Zhu <hongxing.zhu@xxxxxxx>
> >
> > Add i.MX8Q PCIe "fsl,imx8q-pcie" compatible strings.
> >
> > Add "fsl,local-address" property for i.MX8Q platforms. fsl,local-address
> > is address of PCIe module in high speed io (HSIO)subsystem bus fabric. HSIO
> > bus fabric convert the incoming address base to this local-address. Two
> > instances of PCI have difference local address.
>
> This is just some intermediate bus address? We really should be able to
> describe this with standard ranges properties.

Yes, Maybe dwc's implement have some problem. After read below doc again
https://elinux.org/Device_Tree_Usage#PCI_Address_Translation

┌──────┐ ┌──────────┐
┌────┐0x18001000 │ │ │ │
│CPU ├───────────►│ ├──┤ Others │
└────┘ │ │ │ │
│ │ └──────────┘
│ │
│ │ ┌─────────┐
│ │ │ │ ┌───────────┐
│ ├──►│ HSIO │ 0xB8001000 ├───────────┤
│ │ │ Fabric ├───────────►│Bar0 │ TLP mem 0xB8001000
│ │ │ │ │0xB8000000 ├───────►
└──────┘ └─────────┘ │ │
Main Fabric ├───────────┤
│ │
│ │
│ │
│ │
│ │
│ │
│ DWC │
│ PCIe │
│ Controller│
│ │
│ │
└───────────┘


dts should be

ranges = <0x82000000 0 0xB8000000 0x18000000 0 0x07f00000>
^^^^

u64 imx_pcie_cpu_addr_fixup(struct dw_pcie *pcie, u64 cpu_addr)
offset = entry->res->start;
{
...
return (cpu_addr - entry->offset);
}

NVME can work. let me do more test.

Frank
>
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> > .../devicetree/bindings/pci/fsl,imx6q-pcie-common.yaml | 5 +++++
> > .../devicetree/bindings/pci/fsl,imx6q-pcie.yaml | 18 ++++++++++++++++++
> > 2 files changed, 23 insertions(+)