[PATCH V3 2/5] dt-bindings: PCI: tegra: Add DT support for PCIe EP nodes in Tegra194

From: Vidya Sagar
Date: Mon Jan 13 2020 - 13:14:37 EST


Add support for PCIe controllers that can operate in endpoint mode
in Tegra194.

Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
V3:
* Added Reviewed-by: Rob Herring <robh@xxxxxxxxxx>

V2:
* Addressed Thierry's review comments
* Merged EP specific information from tegra194-pcie-ep.txt to tegra194-pcie.txt itself
* Started using the standard 'reset-gpios' for PERST GPIO
* Added 'nvidia,refclk-select-gpios' to enable REFCLK signals

.../bindings/pci/nvidia,tegra194-pcie.txt | 125 ++++++++++++++----
1 file changed, 99 insertions(+), 26 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
index b739f92da58e..faa3ef5adfbb 100644
--- a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
@@ -1,11 +1,11 @@
NVIDIA Tegra PCIe controller (Synopsys DesignWare Core based)

-This PCIe host controller is based on the Synopsis Designware PCIe IP
+This PCIe controller is based on the Synopsis Designware PCIe IP
and thus inherits all the common properties defined in designware-pcie.txt.
+Some of the controller instances are dual mode where in they can work either
+in root port mode or endpoint mode but one at a time.

Required properties:
-- compatible: For Tegra19x, must contain "nvidia,tegra194-pcie".
-- device_type: Must be "pci"
- power-domains: A phandle to the node that controls power to the respective
PCIe controller and a specifier name for the PCIe controller. Following are
the specifiers for the different PCIe controllers
@@ -32,6 +32,32 @@ Required properties:
entry for each entry in the interrupt-names property.
- interrupt-names: Must include the following entries:
"intr": The Tegra interrupt that is asserted for controller interrupts
+- clocks: Must contain an entry for each entry in clock-names.
+ See ../clocks/clock-bindings.txt for details.
+- clock-names: Must include the following entries:
+ - core
+- resets: Must contain an entry for each entry in reset-names.
+ See ../reset/reset.txt for details.
+- reset-names: Must include the following entries:
+ - apb
+ - core
+- phys: Must contain a phandle to P2U PHY for each entry in phy-names.
+- phy-names: Must include an entry for each active lane.
+ "p2u-N": where N ranges from 0 to one less than the total number of lanes
+- nvidia,bpmp: Must contain a pair of phandle to BPMP controller node followed
+ by controller-id. Following are the controller ids for each controller.
+ 0: C0
+ 1: C1
+ 2: C2
+ 3: C3
+ 4: C4
+ 5: C5
+- vddio-pex-ctl-supply: Regulator supply for PCIe side band signals
+
+RC mode:
+- compatible: Tegra19x must contain "nvidia,tegra194-pcie"
+- device_type: Must be "pci" for RC mode
+- interrupt-names: Must include the following entries:
"msi": The Tegra interrupt that is asserted when an MSI is received
- bus-range: Range of bus numbers associated with this controller
- #address-cells: Address representation for root ports (must be 3)
@@ -60,27 +86,15 @@ Required properties:
- interrupt-map-mask and interrupt-map: Standard PCI IRQ mapping properties
Please refer to the standard PCI bus binding document for a more detailed
explanation.
-- clocks: Must contain an entry for each entry in clock-names.
- See ../clocks/clock-bindings.txt for details.
-- clock-names: Must include the following entries:
- - core
-- resets: Must contain an entry for each entry in reset-names.
- See ../reset/reset.txt for details.
-- reset-names: Must include the following entries:
- - apb
- - core
-- phys: Must contain a phandle to P2U PHY for each entry in phy-names.
-- phy-names: Must include an entry for each active lane.
- "p2u-N": where N ranges from 0 to one less than the total number of lanes
-- nvidia,bpmp: Must contain a pair of phandle to BPMP controller node followed
- by controller-id. Following are the controller ids for each controller.
- 0: C0
- 1: C1
- 2: C2
- 3: C3
- 4: C4
- 5: C5
-- vddio-pex-ctl-supply: Regulator supply for PCIe side band signals
+
+EP mode:
+In Tegra194, Only controllers C0, C4 & C5 support EP mode.
+- compatible: Tegra19x must contain "nvidia,tegra194-pcie-ep"
+- reg-names: Must include the following entries:
+ "addr_space": Used to map remote RC address space
+- reset-gpios: Must contain a phandle to a GPIO controller followed by
+ GPIO that is being used as PERST input signal. Please refer to pci.txt
+ document.

Optional properties:
- pinctrl-names: A list of pinctrl state names.
@@ -104,6 +118,8 @@ Optional properties:
specified in microseconds
- nvidia,aspm-l0s-entrance-latency-us: ASPM L0s entrance latency to be
specified in microseconds
+
+RC mode:
- vpcie3v3-supply: A phandle to the regulator node that supplies 3.3V to the slot
if the platform has one such slot. (Ex:- x16 slot owned by C5 controller
in p2972-0000 platform).
@@ -111,11 +127,18 @@ Optional properties:
if the platform has one such slot. (Ex:- x16 slot owned by C5 controller
in p2972-0000 platform).

+EP mode:
+- nvidia,refclk-select-gpios: Must contain a phandle to a GPIO controller
+ followed by GPIO that is being used to enable REFCLK to controller from host
+
+NOTE:- On Tegra194's P2972-0000 platform, only C5 controller can be enabled to
+operate in the endpoint mode because of the way the platform is designed.
+
Examples:
=========

-Tegra194:
---------
+Tegra194 RC mode:
+-----------------

pcie@14180000 {
compatible = "nvidia,tegra194-pcie", "snps,dw-pcie";
@@ -169,3 +192,53 @@ Tegra194:
<&p2u_hsio_5>;
phy-names = "p2u-0", "p2u-1", "p2u-2", "p2u-3";
};
+
+Tegra194 EP mode:
+-----------------
+
+ pcie_ep@141a0000 {
+ compatible = "nvidia,tegra194-pcie-ep", "snps,dw-pcie-ep";
+ power-domains = <&bpmp TEGRA194_POWER_DOMAIN_PCIEX8A>;
+ reg = <0x00 0x141a0000 0x0 0x00020000 /* appl registers (128K) */
+ 0x00 0x3a040000 0x0 0x00040000 /* iATU_DMA reg space (256K) */
+ 0x00 0x3a080000 0x0 0x00040000 /* DBI reg space (256K) */
+ 0x1c 0x00000000 0x4 0x00000000>; /* Address Space (16G) */
+ reg-names = "appl", "atu_dma", "dbi", "addr_space";
+
+ num-lanes = <8>;
+ num-ib-windows = <2>;
+ num-ob-windows = <8>;
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&clkreq_c5_bi_dir_state>;
+
+ clocks = <&bpmp TEGRA194_CLK_PEX1_CORE_5>;
+ clock-names = "core";
+
+ resets = <&bpmp TEGRA194_RESET_PEX1_CORE_5_APB>,
+ <&bpmp TEGRA194_RESET_PEX1_CORE_5>;
+ reset-names = "apb", "core";
+
+ interrupts = <GIC_SPI 53 IRQ_TYPE_LEVEL_HIGH>; /* controller interrupt */
+ interrupt-names = "intr";
+
+ nvidia,bpmp = <&bpmp 5>;
+
+ nvidia,aspm-cmrt-us = <60>;
+ nvidia,aspm-pwr-on-t-us = <20>;
+ nvidia,aspm-l0s-entrance-latency-us = <3>;
+
+ vddio-pex-ctl-supply = <&vdd_1v8ao>;
+
+ reset-gpios = <&gpio TEGRA194_MAIN_GPIO(GG, 1) GPIO_ACTIVE_LOW>;
+
+ nvidia,refclk-select-gpios = <&gpio_aon TEGRA194_AON_GPIO(AA, 5)
+ GPIO_ACTIVE_HIGH>;
+
+ phys = <&p2u_nvhs_0>, <&p2u_nvhs_1>, <&p2u_nvhs_2>,
+ <&p2u_nvhs_3>, <&p2u_nvhs_4>, <&p2u_nvhs_5>,
+ <&p2u_nvhs_6>, <&p2u_nvhs_7>;
+
+ phy-names = "p2u-0", "p2u-1", "p2u-2", "p2u-3", "p2u-4",
+ "p2u-5", "p2u-6", "p2u-7";
+ };
--
2.17.1