From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tao Ren <taoren@fb.com>
Date: Thu, 8 Nov 2018 00:18:29 +0000
Subject: [PATCH v2 1/2] ARM: dts: Add Facebook BMC flash layout
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References: <20181106042829.2771226-1-taoren@fb.com>
 <1541635320.1462459.1569430616.0F5E4C4D@webmail.messagingengine.com>
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On 11/7/18 4:02 PM, Andrew Jeffery wrote:
>> +partitions {
>> +	compatible = "fixed-partitions";
>> +	#address-cells = <1>;
>> +	#size-cells = <1>;
>> +
>> +	u-boot at 0 {
>> +		reg = <0x0 0x60000>;
>> +		label = "u-boot";
>> +	};
>> +
>> +	u-boot-env at 60000 {
>> +		reg = <0x60000 0x20000>;
>> +		label = "env";
>> +	};
>> +
>> +	fit at 80000 {
>> +		reg = <0x80000 0x1b80000>;
>> +		label = "fit";
>> +	};
>> +
>> +	data0 at 1c00000 {
>> +		reg = <0x1c00000 0x400000>;
>> +		label = "data0";
>> +	};
>> +
>> +	flash0 at 0 {
>> +		reg = <0x0 0x2000000>;
>> +		label = "flash0";
>> +	};
> 
> Is this necessary? Isn't the same thing achieved with the /dev/mtd0 device?

Hi Andrew,

Thank you for the review! The new layout file is needed mainly because of "data0" partition: several facebook platforms use the partition as "persistent" storage.

As for "flash0", technically it's not needed (as you pointed out, /dev/mtd0 covers the entire flash if master_partition is enabled). It's still here to avoid breaking some legacy applications.


Thanks,
Tao Ren