Introduce `reset-gpios` property to enable GPIO-based control of
the PCIe RP PERST# signal, generating assert and deassert signals.
Traditionally, the reset was managed in hardware and enabled during
initialization. With this patch set, the reset will be handled by the
driver. Consequently, the `reset-gpios` property must be explicitly
provided to ensure proper functionality.
Add CPM clock and reset control registers base to handle PCIe IP
reset along with PCIe RP PERST# to avoid Link Training errors.
Signed-off-by: Sai Krishna Musham <sai.krishna.musham@xxxxxxx>
---
Changes for v4:
- Add CPM clock and reset control registers base to handle PCIe IP
reset.
- Update commit message.
Changes for v3:
- None
Changes for v2:
- Add define from include/dt-bindings/gpio/gpio.h for PERST# polarity
- Update commit message
---
.../bindings/pci/xilinx-versal-cpm.yaml | 21 ++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
index d674a24c8ccc..904594138af2 100644
--- a/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
+++ b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
@@ -24,15 +24,20 @@ properties:
items:
- description: CPM system level control and status registers.
- description: Configuration space region and bridge registers.
+ - description: CPM clock and reset control registers.
- description: CPM5 control and status registers.
- minItems: 2
+ minItems: 3
reg-names:
items:
- const: cpm_slcr
- const: cfg
+ - const: cpm_crx
- const: cpm_csr
- minItems: 2
+ minItems: 3
+
+ reset-gpios:
+ description: GPIO used as PERST# signal
interrupts:
maxItems: 1
@@ -64,6 +69,7 @@ properties:
required:
- reg
- reg-names
+ - reset-gpios
- "#interrupt-cells"
- interrupts
- interrupt-map
@@ -76,6 +82,7 @@ unevaluatedProperties: false
examples:
- |
+ #include <dt-bindings/gpio/gpio.h>
versal {
#address-cells = <2>;
@@ -98,8 +105,10 @@ examples:
<0x43000000 0x80 0x00000000 0x80 0x00000000 0x0 0x80000000>;
msi-map = <0x0 &its_gic 0x0 0x10000>;
reg = <0x0 0xfca10000 0x0 0x1000>,
- <0x6 0x00000000 0x0 0x10000000>;
- reg-names = "cpm_slcr", "cfg";
+ <0x6 0x00000000 0x0 0x10000000>,
+ <0x0 0xfca00000 0x0 10000>;
+ reg-names = "cpm_slcr", "cfg", "cpm_crx";
+ reset-gpios = <&gpio1 38 GPIO_ACTIVE_LOW>;
pcie_intc_0: interrupt-controller {
#address-cells = <0>;
#interrupt-cells = <1>;
@@ -126,8 +135,10 @@ examples:
msi-map = <0x0 &its_gic 0x0 0x10000>;
reg = <0x00 0xfcdd0000 0x00 0x1000>,
<0x06 0x00000000 0x00 0x1000000>,
+ <0x00 0xfcdc0000 0x00 0x10000>,
<0x00 0xfce20000 0x00 0x1000000>;
- reg-names = "cpm_slcr", "cfg", "cpm_csr";
+ reg-names = "cpm_slcr", "cfg", "cpm_crx", "cpm_csr";
+ reset-gpios = <&gpio1 38 GPIO_ACTIVE_LOW>;
pcie_intc_1: interrupt-controller {
#address-cells = <0>;
--
2.44.1
