Re: [PATCH v3 1/3] ARM: dts: NSP: Enable SFP on bcm958625hr

From: Ray Jui
Date: Tue Sep 04 2018 - 16:39:39 EST




On 8/31/2018 12:20 PM, Florian Fainelli wrote:
Enable the SFP connected to port 5 of the switch and wire up all GPIOs
to the SFP cage. Because of a hardware limitation of the i2c controller
on the iProc SoCs which prevents large i2c (> 63 bytes) transactions to
work, we use the i2c-gpio interface instead, which does not have that
limitation. This allows us to read the SFP module EEPROM, which would
not be possible otherwise since it exceeds that size during a single
read transfer.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
arch/arm/boot/dts/bcm958625hr.dts | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/arch/arm/boot/dts/bcm958625hr.dts b/arch/arm/boot/dts/bcm958625hr.dts
index ea3fc194f8f3..a53a2f629d74 100644
--- a/arch/arm/boot/dts/bcm958625hr.dts
+++ b/arch/arm/boot/dts/bcm958625hr.dts
@@ -58,6 +58,24 @@
open-source;
priority = <200>;
};
+
+ /* Hardware I2C block cannot do more than 63 bytes per transfer,
+ * which would prevent reading from a SFP's EEPROM (256 byte).
+ */
+ i2c1: i2c {
+ compatible = "i2c-gpio";
+ sda-gpios = <&gpioa 5 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ scl-gpios = <&gpioa 4 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ };
+
+ sfp: sfp {
+ compatible = "sff,sfp";
+ i2c-bus = <&i2c1>;
+ mod-def0-gpios = <&gpioa 28 GPIO_ACTIVE_LOW>;
+ los-gpios = <&gpioa 24 GPIO_ACTIVE_HIGH>;
+ tx-fault-gpios = <&gpioa 30 GPIO_ACTIVE_HIGH>;
+ tx-disable-gpios = <&gpioa 26 GPIO_ACTIVE_HIGH>;
+ };
};
&amac0 {
@@ -210,6 +228,14 @@
reg = <4>;
};
+ port@5 {
+ label = "sfp";
+ phy-mode = "sgmii";
+ reg = <5>;
+ sfp = <&sfp>;
+ managed = "in-band-status";
+ };
+
port@8 {
ethernet = <&amac2>;
label = "cpu";


Looks good to me. Thanks!

Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>