Hello Jeffrey,
 

I have a similar question to Mohamed, and I'm not sure it was resolved in 
the following threads. 

I don't mind losing i2c2, so what I did was follow the http://www.aero-
box.co.uk/beaglebone-black#TOC-Enable-CANbus-device page, except since I 
want both dcan0 and dcan1, I removed the entry: 

                i2c2_pins: pinmux_i2c2_pins {
			pinctrl-single,pins = <
				0x178 0x73 	
				0x17c 0x73	

			>;
		};

It's not necessary to delete this lines if you disable the i2c2 later in the same file here:
----------------
&i2c2 {
	status = "disabled";
.
.
. 
----------------

and replaced it with 

                dcan0_pins: pinmux_dcan0_pins {
			pinctrl-single,pins = <
				0x178 0x12
				0x17c 0x32
			>; 

		};

		dcan1_pins: pinmux_dcan1_pins {
			pinctrl-single,pins = <
				0x180 0x12
				0x184 0x32
			>; 
		}; 

The dcan0/dcan1 settings are fine!
 

Then, as with the tutorial, made: 

                uart2: serial@48022000 {
                        status = "disabled";

                };

and added in: 

		dcan1: d_can@481d0000 {
			status = "okay";
			pinctrl-names = "default"; 
			pinctrl-0 = <&dcan1_pins>;  
		};

		dcan0: d_can@481cc000 {
			status = "okay"; 
			pinctrl-names = "default"; 
			pinctrl-0 = <&dcan0_pins>; 
		};  

Its also correct.
 

In the spirit of stripping out all the i2c2 references, I got ride of 

&i2c2 {
	status = "okay";
	pinctrl-names = "default";
	pinctrl-0 = <&i2c2_pins>;

	clock-frequency = <100000>;

	cape_eeprom0: cape_eeprom0@54 {
		compatible = "at,24c256";
		reg = <0x54>;
	};

	cape_eeprom1: cape_eeprom1@55 {
		compatible = "at,24c256";
		reg = <0x55>;
	};

	cape_eeprom2: cape_eeprom2@56 {
		compatible = "at,24c256";
		reg = <0x56>;
	};

	cape_eeprom3: cape_eeprom3@57 {
		compatible = "at,24c256";
		reg = <0x57>;
	};
};

Thats not necessary as mentioned above, you can only set status = "okay" to status = "disabled" but deleting the stuff should have the same result.

I can bring up can0, but not can1: 

root@beaglebone:~# canconfig can0 bitrate 10000 ctrlmode triple-sampling on
can0 bitrate: 10000, sample-point: 0.875
can0 ctrlmode: loopback[OFF], listen-only[OFF], tripple-sampling[ON],one-
shot[OFF], berr-reporting[OFF]
root@beaglebone:~# canconfig can0 start
can0 state: ERROR-ACTIVE
root@beaglebone:~# canconfig can1 bitrate 10000 ctrlmode triple-sampling on
can1: failed to get bitrate

root@beaglebone:~# canconfig can1 stop
can1: failed to get state
root@beaglebone:~# canconfig can1 start
can1: failed to get state

I think I'm fundamentally missing something; do you have any pointers on 
this? 

Did you use this dtc command line?
dtc -O dtb -o am335x-boneblack.dtb -b 0 am335x-boneblack.dts

I've seen an issue on my Debian based Beaglebone where the "-b 0" patch isn't available with my am335x-boneblack.dtb so can say it is a must to use the "-b 0" option.

DCAN0 seems to be OK. 
Can you provide the dmesg output for DCAN0 and DCAN1. Maybe there are some helpful information what happens during initialization.

Regards
Mike