Linux/AM5728: DCAN communication

OK,thanks for the suggestion ,I have changed the sdk to ti-processor-sdk-linux-rt-am57xx-evm-04.01.00.06.

And good news is that problem 1 is solved.

# canconfig can0 bitrate 50000 ctrlmode triple-sampling on
can0 bitrate: 50000, sample-point: 0.875
can0 ctrlmode: loopback[OFF], listen-only[OFF], tripple-sampling[ON],one-shot[OFF], berr-reporting[OFF]

But there is a error print by kernel says :

omap_hwmod: dcan1: _wait_target_disable failed

And problem 2 remains.

The am57xx-beagle-x15-revb1.dtb TI provide don't  have dcan when boot up.

I have modified  the dtsi like:

	dcan1_pins_ds: pinmux_dcan1_pins_ds {
		pinctrl-single,pins = <
			DRA7XX_CORE_IOPAD(0x37d4, PIN_INPUT | MUX_MODE0) 	/* (Errata i893) dcan1_rx.dcan1_rx */
			DRA7XX_CORE_IOPAD(0x37d0, PIN_OUTPUT | MUX_MODE0) 	/* dcan1_tx.dcan1_tx */
		>;
	}; 

&dcan1 {
	status = "okay";    /* Enable only if Profile 1 is selected */
    pinctrl-names = "default";
    pinctrl-0 = <&dcan1_pins_ds>;
};

And as what I sayed before ,I followed the DCAN_GUIDE ,and chose dcan_driver to "y" in the  zImage I am using right now.

Hi ,thanks for reply.
I was wrong about my last comment "The am57xx-beagle-x15-revb1.dtb TI provide don't have dcan when boot up."
Today I notice that there is a can interface for debug on AM57xx_idk_board .I download the lastest SDK ti-processor-sdk-linux-rt-am57xx-evm-05.00.00.15, and try can communication between 2 idk_board.

It works perfetly .

Question is still how should I modify the dts for bb_x15 .I have no idea.(the dtb for idk_board don't work for bb_x15)

1."I want to make sure you modified the correct file, which dtsi did you modify? "

I modify "bb-x15/ti-linux-kernel-dev/KERNEL/arch/arm/boot/dts/am57xx-beagle-x15-revc.dts",

/*
 * Copyright (C) 2014-2017 Texas Instruments Incorporated - http://www.ti.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include "am57xx-beagle-x15-common.dtsi"
#include "am57xx-cmem.dtsi"

/ {
	model = "TI AM5728 BeagleBoard-X15 rev C";
};

&tpd12s015 {
	gpios = <&gpio7 10 GPIO_ACTIVE_HIGH>,	/* gpio7_10, CT CP HPD */
		<&gpio2 30 GPIO_ACTIVE_HIGH>,	/* gpio2_30, LS OE */
		<&gpio7 12 GPIO_ACTIVE_HIGH>;	/* gpio7_12/sp1_cs2, HPD */
};

&dra7_pmx_core {
	dcan1_pins_ds: pinmux_dcan1_pins_ds {
		pinctrl-single,pins = <
			DRA7XX_CORE_IOPAD(0x37d4, PIN_INPUT | MUX_MODE0) 	/* (Errata i893) dcan1_rx.dcan1_rx */
			DRA7XX_CORE_IOPAD(0x37d0, PIN_OUTPUT | MUX_MODE0) 	/* dcan1_tx.dcan1_tx */
		>;
	};

};




&mmc1 {
	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
	pinctrl-0 = <&mmc1_pins_default>;
	pinctrl-1 = <&mmc1_pins_hs>;
	pinctrl-2 = <&mmc1_pins_sdr12>;
	pinctrl-3 = <&mmc1_pins_sdr25>;
	pinctrl-4 = <&mmc1_pins_sdr50>;
	pinctrl-5 = <&mmc1_pins_ddr50 &mmc1_iodelay_ddr_rev20_conf>;
	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev20_conf>;
	vmmc-supply = <&vdd_3v3>;
	vmmc_aux-supply = <&ldo1_reg>;
};

&mmc2 {
	pinctrl-names = "default", "hs", "ddr_1_8v";
	pinctrl-0 = <&mmc2_pins_default>;
	pinctrl-1 = <&mmc2_pins_hs>;
	pinctrl-2 = <&mmc2_pins_ddr_rev20>;
};



&dcan1 {
	status = "okay";    /* Enable only if Profile 1 is selected */
    pinctrl-names = "default";
    pinctrl-0 = <&dcan1_pins_ds>;
};

2. "/* Enable only if Profile 1 is selected */, did copy this to the X15 dts file?"

Maybe you hit the point ,I haven't notice this . Do you have ideas about what this Profile 1 mean or where it exits?

I found that profile 1 ,is a hardware switch for AM335x GP EVM.So this is not the reason

processors.wiki.ti.com/.../Linux_Core_DCAN_User's_Guide

root@am57xx-evm:~# devmem2 0x4AE07888 h
/dev/mem opened.
Memory mapped at address 0xb6fe9000.
Read at address  0x4AE07888 (0xb6fe9888): 0x0000
root@am57xx-evm:~# canconfig can0 bitrate 50000 ctrlmode triple-samplin
[  757.361582] omap_hwmod: dcan1: _wait_target_disable failed
can0 bitrate: 50000, sample-point: 0.875                               
[  757.376837] omap_hwmod: dcan1: _wait_target_disable failed          
can0 ctrlmode: loopback[OFF], listen-only[OFF], tripple-sampling[ON],o]
root@am57xx-evm:~# ifconfig can0 up                                    
[  763.253046] c_can_platform 4ae3c000.can can0: setting BTR=1c18 BRPE0
root@am57xx-evm:~# devmem2 0x4AE07888 h                                
/dev/mem opened.                                                       
Memory mapped at address 0xb6f43000.                                   
Read at address  0x4AE07888 (0xb6f43888): 0x0002                       
root@am57xx-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 8
interface = can0, family = 29, type = 3, proto = 1                     
root@am57xx-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 8
interface = can0, family = 29, type = 3, proto = 1                     
root@am57xx-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 8
interface = can0, family = 29, type = 3, proto = 1                     
root@am57xx-evm:~#

0x4AE07888 is the dcan1_clkctrl address. And dcan1_tx ouput shows  nothing(using a scope) 

root@am57xx-evm:~# canconfig can0 bitrate 50000 ctrlmode triple-sampling on

[  757.361582] omap_hwmod: dcan1: _wait_target_disable failed
can0 bitrate: 50000, sample-point: 0.875                               
[  757.376837] omap_hwmod: dcan1: _wait_target_disable failed          
can0 ctrlmode: loopback[OFF], listen-only[OFF], tripple-sampling[ON],...

root@am57xx-evm:~# ifconfig can0 up                                  
[  763.253046] c_can_platform 4ae3c000.can can0: setting BTR=1c18 BRPE0
                    
root@am57xx-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 8
interface = can0, family = 29, type = 3, proto = 1                     
                    
root@am57xx-evm:~#

1.This is the command I used to configure CAN on bb_x15 , actually I have mentioned this in my last post.

2.This is the output of " lsmod | grep can "

root@am57xx-evm:~# lsmod | grep can                                
can_raw                 6589  2                                              
can                    29904  1 can_raw                                      
c_can_platform          6638  0         
c_can                   9718  1 c_can_platform
can_dev                12397  1 c_can   

3.One last question :Have you(or your staff) ever test can on bb_x15? ( No offense)

And  now I am using the  same sd_card(same zImage,same dtb,same u-boot),and both am5728_idk and bb_x15 can successfully boot-up,but bb_x15 still has problem with can communication while am5728_idk works perfectly .Will this  omap_hwmod: dcan1: _wait_target_disable failed be a hardware problem ?

Thanks a lot for the reply.

1.The reason why we are using bb_x15 instead of idk_board : bb_x15 is smaller (and besides ,cheaper .Actually it's the boss 's choice -_- )

2.The result of "cat /proc/device-tree/ocp/can\@481cc000/status" is :

root@am57xx-evm:~# cat /proc/device-tree/ocp/can\@481cc000/status      
okay

on arch/arm/mach-omap2/omap_hwmod.c 

line:1845

/**
 * _omap4_disable_module - enable CLKCTRL modulemode on OMAP4
 * @oh: struct omap_hwmod *
 *
 * Disable the PRCM module mode related to the hwmod @oh.
 * Return EINVAL if the modulemode is not supported and 0 in case of success.
 */
static int _omap4_disable_module(struct omap_hwmod *oh)
{
	int v;

	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
		return -EINVAL;

	/*
	 * Since integration code might still be doing something, only
	 * disable if all lines are under hardreset.
	 */
	if (_are_any_hardreset_lines_asserted(oh))
		return 0;

	pr_debug("omap_hwmod: %s: %s\n", oh->name, __func__);

	omap_cm_module_disable(oh->clkdm->prcm_partition, oh->clkdm->cm_inst,
			       oh->prcm.omap4.clkctrl_offs);

	v = _omap4_wait_target_disable(oh);
	if (v)
		pr_warn("omap_hwmod: %s: _wait_target_disable failed\n",
			oh->name);

	return 0;
}

No dcan error message on idk_board

Hi ,  Schuyler

1.

Bruno Lui  ,he add a 5V power supply to beagle-bone-black's   "CBB-Serial cape ".But I have no idea where this so call 5V is add to .

2.Do you think disabling HDMI will help ? I search and found people disable HDMI while developing CAN on BBB.

And how should I check the status of HDMI on bb_x15?

Hi ,Schuyler

1.Now I use am572x-idk.dtb, its dts is like

/*
 * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

/dts-v1/;

#include "dra74x.dtsi"
#include "am572x-idk-common.dtsi"
#include "dra74x-mmc-iodelay.dtsi"

/ {
	model = "TI AM5728 IDK";
	compatible = "ti,am5728-idk", "ti,am5728", "ti,dra742", "ti,dra74",
		     "ti,dra7";
};

&cpu0 {
	vdd-supply = <&smps12_reg>;
};

&mmc1 {
	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
	pinctrl-0 = <&mmc1_pins_default>;
	pinctrl-1 = <&mmc1_pins_hs>;
	pinctrl-2 = <&mmc1_pins_sdr12>;
	pinctrl-3 = <&mmc1_pins_sdr25>;
	pinctrl-4 = <&mmc1_pins_sdr50>;
	pinctrl-5 = <&mmc1_pins_ddr50 &mmc1_iodelay_ddr_rev20_conf>;
	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev20_conf>;
};

&mmc2 {
	pinctrl-names = "default", "hs", "ddr_1_8v";
	pinctrl-0 = <&mmc2_pins_default>;
	pinctrl-1 = <&mmc2_pins_hs>;
	pinctrl-2 = <&mmc2_pins_ddr_rev20>;
};

&pruss2_mdio {
	reset-gpios = <&gpio5 8 GPIO_ACTIVE_LOW>,
		      <&gpio5 9 GPIO_ACTIVE_LOW>;
	reset-delay-us = <2>;	/* PHY datasheet states 1uS min */
};

#include "am57xx-evm-cmem.dtsi"

And am572x-idk.dts  includes am572x-idk-common.dtsi which already defined the pins you mentioned 

&dra7_pmx_core {
	dcan1_pins_default: dcan1_pins_default {
		pinctrl-single,pins = <
			DRA7XX_CORE_IOPAD(0x37d0, PIN_OUTPUT_PULLUP | MUX_MODE0)	/* dcan1_tx */
			DRA7XX_CORE_IOPAD(0x37d4, PIN_INPUT_PULLUP | MUX_MODE0)		/* dcan1_rx */
		>;
	};

	dcan1_pins_sleep: dcan1_pins_sleep {
		pinctrl-single,pins = <
			DRA7XX_CORE_IOPAD(0x37d0, MUX_MODE15 | PULL_UP)	/* dcan1_tx.off */
			DRA7XX_CORE_IOPAD(0x37d4, MUX_MODE15 | PULL_UP)	/* dcan1_rx.off */
		>;
	};
};


&dcan1 {
	status = "okay";
	pinctrl-names = "default", "sleep", "active";
	pinctrl-0 = <&dcan1_pins_sleep>;
	pinctrl-1 = <&dcan1_pins_sleep>;
	pinctrl-2 = <&dcan1_pins_default>;
};

2. Dcan is not working still.