Hi,
I have a custom board which is based on imx7dsabresd. I am using "linux-imx-4.1.15". I am trying to bring up uart7 but no success. I don't see any data coming out on uart7_Tx.
UART7_RX and UART7_TX are on the pads EPDC_DATA12 and EPDC_DATA13 respectively. I have attached the schematics for the same. The dts changes are as below
In the file "imx7d.dtsi"
uart7: serial@30a90000 {
compatible = "fsl,imx7d-uart",
"fsl,imx6q-uart", "fsl,imx21-uart";
reg = <0x30a90000 0x10000>;
interrupts = <GIC_SPI 126 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks IMX7D_UART7_ROOT_CLK>,
<&clks IMX7D_UART7_ROOT_CLK>;
clock-names = "ipg", "per";
dmas = <&sdma 34 4 0>, <&sdma 35 4 0>;
dma-names = "rx", "tx";
status = "okay";
};
In the file "imx7d-sdb.dts"
&uart7 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart7>;
assigned-clocks = <&clks IMX7D_UART7_ROOT_SRC>;
assigned-clock-parents = <&clks IMX7D_OSC_24M_CLK>;
status = "okay";
};
&iomuxc {
...
...
imx7d-sdb
{
...
...
pinctrl_uart7: uart7grp {
fsl,pins = <
MX7D_PAD_EPDC_DATA12__UART7_DCE_RX 0x79
MX7D_PAD_EPDC_DATA13__UART7_DCE_TX 0x79
>;
};
...
...
}
...
...
}
Kindly, help me to solve this issue.
Thanks & Regards
Vijay H.S
Hi Vijay
one can try to change "assigned-clock-parents" as in uart6 in dts example
imx7d-sdb.dts\dts\boot\arm\arch - linux-imx - i.MX Linux kernel
Best regards
igor
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Hi Igor,
Thanks for the reply.
I tried with
assigned-clock-parents = <&clks IMX7D_PLL_SYS_MAIN_240M_CLK>;
which is same as uart6, but still no success.
Regards
Vijay H.S
Hi Vijay
one can try to debug it: check if clocks are enabled in CCM_CCGR154
(uart7), write some data to UARTx_UTXD, check signal with oscilloscope.
Debugging Linux Kernel over JTAG with J-Link
Best regards
igor