On Fri, Jan 10, 2025 at 10:17:15AM -0600, Andrew Davis wrote: > On 1/10/25 9:35 AM, Rob Herring wrote: > > On Fri, Jan 10, 2025 at 11:03:30AM +0100, Romain Naour wrote: > > > From: Romain Naour <romain.naour@xxxxxxx> > > > > > > The ACSPCIE_PROXY_CTRL registers within the CTRL_MMR space of TI's J721e > > > SoC are used to drive the reference clock to the PCIe Endpoint device via > > > the PAD IO Buffers. Add the compatible for allowing the PCIe driver to > > > obtain the regmap for the ACSPCIE_CTRL register within the System > > > Controller device-tree node in order to enable the PAD IO Buffers. > > > > > > Using the ti,j721e-acspcie-proxy-ctrl compatible imply to use "Proxy1" > > > address (1A090h) instead of "Proxy0" (18090h) to access > > > CTRLMMR_ACSPCIE0_CTRL register: > > > > > > CTRLMMR_ACSPCIE0_CTRL Register (Proxy0 Offset = 18090h; Proxy1 Offset = 1A090h) > > > > > > "Proxy0" is used as the default access path that can be locked with the > > > help of "CTRLMMR_LOCK0_KICK0" and "CTRLMMR_LOCK0_KICK1" registers. > > > > > > The Technical Reference Manual for J721e SoC with details of the > > > ASCPCIE_CTRL registers is available at: > > > https://www.ti.com/lit/zip/spruil1 > > > > > > Signed-off-by: Romain Naour <romain.naour@xxxxxxx> > > > --- > > > v5: > > > - Add missing change to the J721e system controller binding > > > to avoid DT check warning when the new acspcie0_proxy_ctrl (syscon) > > > will be added to J721e system controller node (Andrew Davis). > > > > > > https://lore.kernel.org/linux-devicetree/90f47fae-a493-471d-8fe6-e7df741161be@xxxxxx/ > > > > > > - Explain why "Proxy1" address (1A090h) should be used while using > > > ti,j721e-acspcie-proxy-ctrl compatible (Siddharth Vadapalli). > > > > > > https://lore.kernel.org/linux-devicetree/begojbvvrpyjfr3pye7mqwiw73ucw5ynepdfujssr4jx4vs33a@pwahnph3qesl/ > > > > > > v4: Add missing change in the second list (From Andrew Davis) [1] > > > Rebase after the ti,j784s4-acspcie-proxy-ctrl compatible fix [2] > > > [1] https://lore.kernel.org/linux-devicetree/20250103174524.28768-1-afd@xxxxxx/ > > > [2] https://lore.kernel.org/linux-devicetree/20250103174524.28768-2-afd@xxxxxx/ > > > > > > v3: new commit > > > --- > > > Documentation/devicetree/bindings/mfd/syscon.yaml | 2 ++ > > > .../bindings/soc/ti/ti,j721e-system-controller.yaml | 6 ++++++ > > > 2 files changed, 8 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/mfd/syscon.yaml b/Documentation/devicetree/bindings/mfd/syscon.yaml > > > index 0e68c69e7bc9..1f3e67f432e7 100644 > > > --- a/Documentation/devicetree/bindings/mfd/syscon.yaml > > > +++ b/Documentation/devicetree/bindings/mfd/syscon.yaml > > > @@ -115,6 +115,7 @@ select: > > > - ti,am625-dss-oldi-io-ctrl > > > - ti,am62p-cpsw-mac-efuse > > > - ti,am654-dss-oldi-io-ctrl > > > + - ti,j721e-acspcie-proxy-ctrl > > > - ti,j784s4-acspcie-proxy-ctrl > > > - ti,j784s4-pcie-ctrl > > > - ti,keystone-pllctrl > > > @@ -213,6 +214,7 @@ properties: > > > - ti,am625-dss-oldi-io-ctrl > > > - ti,am62p-cpsw-mac-efuse > > > - ti,am654-dss-oldi-io-ctrl > > > > > + - ti,j721e-acspcie-proxy-ctrl > > > - ti,j784s4-acspcie-proxy-ctrl > > > > How do these 2 compare? Are they compatible? > > > > Yes, they are 100% identical and compatible, but we were told > to make a new string anyway.. [0] > > [0] https://lore.kernel.org/all/1bfdf1f1-7542-4149-a85d-2ac4b659b26b@xxxxxxxxxx/ Then you should have: "ti,j721e-acspcie-proxy-ctrl", "ti,j784s4-acspcie-proxy-ctrl", "syscon" > > > > > - ti,j784s4-pcie-ctrl > > > - ti,keystone-pllctrl > > > diff --git a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml > > > index 378e9cc5fac2..16929218d611 100644 > > > --- a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml > > > +++ b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml > > > @@ -68,6 +68,12 @@ patternProperties: > > > description: > > > The node corresponding to SoC chip identification. > > > + "^syscon@[0-9a-f]+$": > > > + type: object > > > + $ref: /schemas/mfd/syscon.yaml# > > > + description: > > > + This is the ASPCIe control region. > > > > So this is a syscon child of a syscon. The primary reason for 'syscon' > > compatible is to create a regmap. Why can't you use the parent's syscon? > > > > The parent node will not be a syscon soon. We made this whole bus a "syscon" > so we could just poke any register we wanted which was a hacky solution we > want to fix. The parent will be converted into a normal "simple-bus". Sigh... And that can be done without ABI breakage? > Most of the IP in this region can be described using normal DT devices, > but there are still just a couple registers like this where we need a raw > syscon (or we could make a proper device driver for these registers, but > that might be excessive, instead seems easy enough to just poke them > directly from the PCIe driver). Given it was already a syscon, keeping that is fine. Rob
