Linux/AM5718: McSPI configuration

Anil Medak

Part Number: AM5718

Tool/software: Linux

Hi TI,

Facing an issue when enable, MCSPI for my slave protocol driver. After SPI protocol driver registration, the probe call is not hitting.

I made dts changes in am571x-idk.dts:

&mcspi2 {
   status = "okay";
   compatible = "ti,omap4-mcspi", "ti,omap2-mcspi";
   reg = <0x4809a000 0x200>;
   interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>;
   #address-cells = <1>;
   #size-cells = <0>;
   ti,hwmods = "mcspi2";
   ti,spi-num-cs = <2>;
   dmas = <&sdma 43>,
       <&sdma 44>,
       <&sdma 45>,
       <&sdma 46>;
   dma-names = "tx0", "rx0", "tx1", "rx1";

    myspislave: myspislave@1 {
       compatible = "myspislave", "ti,omap4-mcspi", "ti,omap4-mcspi";
       spi-max-frequency = <48000000>;
       reg = <0>; /* chip select 0*/
   };
};

.config:

CONFIG_SPI=y
CONFIG_SPI_DEBUG=y
CONFIG_SPI_MASTER=y

CONFIG_SPI_OMAP24XX=y

Can any one suggest me what all the changes required to process further.

Thanks,

Anil

over 8 years ago

0 Biser Gatchev-XID over 8 years ago

TI__Guru**** 393215 points

Hi,

The AM57x Processor SDK supports only SPI Master mode, as stated here: processors.wiki.ti.com/.../Linux_Core_SPI_User's_Guide Driver development support is out of the scope of this forum, however at a glance you have:

CONFIG_SPI_MASTER=y

which configures the SPI in Master mode.

0 Anil Medak over 8 years ago in reply to Biser Gatchev-XID

Intellectual 430 points

Hi Biser,

I understand, But If I am not wrong, I am trying to add slave device driver(protocol driver) for MCSPI master.

Thanks,
Anil

0 Biser Gatchev-XID over 8 years ago in reply to Anil Medak

TI__Guru**** 393215 points

Oh, I understand now. Have you seen processors.wiki.ti.com/.../Linux_Core_SPI_User's_Guide

0 Anil Medak over 8 years ago in reply to Biser Gatchev-XID

Intellectual 430 points

Hi Biser,

I am facing same issue even for spidev driver to set device tree settings to MCSPI2 controller for an AM5718 board.
The probe (spidev_probe)call is still not hitting.

The DTS changes in am571x-idk.dts:
&mcspi2 {
status = "okay";
pinctrl-names = "default";
spidev@1 {
spi-max-frequency = <24000000>;
reg = <0>;
compatible = "rohm,dh2228fv";
};
};

In .config:
CONFIG_SPI_SPIDEV=y

Can you suggest me what else i am missing.

Thanks,
Anil

0 Pavel Botev over 8 years ago in reply to Anil Medak

TI__Guru**** 170625 points

Hi Anil,

Make sure that McSPI clock is enabled from the device PRCM. Please also provide full boot up console log for analysis.

Regards,
Pavel

0 Anil Medak over 8 years ago in reply to Pavel Botev

Intellectual 430 points

Hi Pavel,
After proper update of dts file spidev probe call is hitting.

Know i want to confirm what pinctrl configuration required for am5718 idk board.
i did like this in am571x-idk.dts file:
&mcspi2 {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&spi2_pins>;
}

spi2_pins: spi2_pins {
pinctrl-single,pins = <
0x17C0 (PULL_DIS | MUX_MODE0) /* spi2_clk */
0x17C8 (INPUT_EN | PULL_DIS | SLEWCONTROL | MUX_MODE0) /* spi2_D0 */
0x17C4 ( PULL_DIS | SLEWCONTROL | MUX_MODE0) /* spi2_D1 */
0x17CC (PULL_DIS | SLEWCONTROL | MUX_MODE0) /* spi2_CS0 */
>;
};
is this the correct info and place to write.

Thanks,
Anil

0 Pavel Botev over 8 years ago in reply to Anil Medak

TI__Guru**** 170625 points

Anil,

Changing McSPI pinmux in linux kernel is not recommended. This should be done in SPL (MLO) stage. Refer to the below pointers for more info:

AM571x silicon errata, i869 IO Glitches Can Occur When Changing IO Settings
AM571x TRM, section "Isolation Requirements"

e2e.ti.com/.../2316413
e2e.ti.com/.../566993

Regards,
Pavel

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Linux/AM5718: McSPI configuration