LPSPI frequency

[ankita_hegde]

Hello Team,

We are using NXP's I.MX8DXL processor with LPSPI for CANFD communication. With this setup we are able to send around 900 can messages per second for 500Kb bit-rate and 1Mb data-bit rate so we want to increase this count.

Currently we have spi-max-frequency as 5MHz so what is the maximum spi frequency in case of lpspi and also by increasing this frequency can we send larger number of messages per second.

this is our dts for reference:

&lpspi2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_lpspi2>;
fsl,spi-num-chipselects = <1>;
cs-gpios = <&lsio_gpio4 22 GPIO_ACTIVE_HIGH>;
status = "okay";

tcan4x5x0: tcan4x5x@0 {
compatible = "ti,tcan4x5x";
reg = <0>;
pinctrl-names = "default";
#address-cells = <1>;
#size-cells = <1>;
spi-max-frequency = <5000000>;
bosch,mram-cfg = <0x0 3 2 32 10 1 32 7>; 
clocks = <&hclk>, <&cclk>;
clock-names = "hclk", "cclk";
interrupt-parent = <&lsio_gpio3>;
interrupts = <12 IRQ_TYPE_EDGE_FALLING>;
data-ready-gpios = <&lsio_gpio3 12 GPIO_ACTIVE_HIGH>;
reset-gpios= <&exp2 12 GPIO_ACTIVE_HIGH>;
iw-tcan-prop;
wakeup-source;
status = "okay";

};
};

Regards,
Ankita

[ankita_hegde]

Hello @Manuel_Salas 

Thank you for the previous reply. We referred the dts file you had sent and made spi frequency as 10MHz but we were able to get only 1020 CAN messages per second.

Basically we want to increase the number of CAN messages received, so is there any suggestion that you can give that will help in increasing this rate.

Regards,

Ankita

[Manuel_Salas]

Hello @ankita_hegde 

I hope you are doing well.

Please refer to the imx8qxp-lpddr4-val-lpspi.dts, there is configured the LPSPI2 to works at 10MHz.

Best regards,

Salas.