[U-Boot] [U-boot][PATCH v2] keystone2: add support for UART download

[Vitaly Andrianov]

On 02/17/2015 12:17 PM, Nishanth Menon wrote:
> On 02/17/2015 10:39 AM, Vitaly Andrianov wrote:
>> Currently to flash u-boot image onto NAND or SPI NOR flash, very first
>> time user need to use Code Composer Studio (CCS). This is cumbersome for
>> an user not familiar with CCS. This patch add simpler procedure using
>> uart boot mode for K2 EVMs.
>>
>> When UART bootmode is set and board is rebooted, the ROM boot loader
>> transfers the image at the beginning of the internal RAM. After the
>> transfer is complete the boot-loader sets the PC to the first internal RAM
>> address 0x0c000000. The u-boot.bin is linked to the address 0x0c001000.
>>
>> In order to use the u-boot.bin as an image for UART download, we need to
>> add 4K zeros prefix that act as 1K NOP instructions before reaching
>> 0xc001000.
>>
>> Signed-off-by: Vitaly Andrianov <vitalya at ti.com>
>> Acked-by: Murali Karicheri <m-karicheri2 at ti.com>
>> Tested-by: Murali Karicheri <m-karicheri2 at ti.com>
>> ---
>> Changes in V2:
>> 	- removed extra EOL
>> 	- "MSMC" replaced by "internal RAM" in the commit message
>>
>>   Makefile                |  6 ++++++
>>   board/ti/ks2_evm/README | 15 +++++++++++++++
>>   2 files changed, 21 insertions(+)
>>
>> diff --git a/Makefile b/Makefile
>> index 36a9a28..7a86cac 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -940,6 +940,12 @@ u-boot-nand.gph: u-boot.bin FORCE
>>   	$(call if_changed,mkimage)
>>   	@dd if=/dev/zero bs=8 count=1 2>/dev/null >> $@
>>
>> +u-boot.uart.pad:
>> +	@dd if=/dev/zero bs=4 count=1024 2>/dev/null > $@
>> +
>> +u-boot.uart: u-boot.uart.pad u-boot.bin FORCE
>> +	$(call if_changed,cat)
>> +
>>   # x86 uses a large ROM. We fill it with 0xff, put the 16-bit stuff (including
>>   # reset vector) at the top, Intel ME descriptor at the bottom, and U-Boot in
>>   # the middle.
>> diff --git a/board/ti/ks2_evm/README b/board/ti/ks2_evm/README
>> index 9ee90a4..7e2e096 100644
>> --- a/board/ti/ks2_evm/README
>> +++ b/board/ti/ks2_evm/README
>> @@ -81,6 +81,21 @@ To build u-boot-nand.gph
>>     >make k2hk_evm_defconfig
>>     >make u-boot-nand.gph
>>
>> +To build u-boot.uart
>> +  >make k2hk_evm_defconfig
>> +  >make u-boot.uart
>> +
>> +Load and Run U-Boot on keystone EVMs using UART download
>> +========================================================
>> +
>> +Open BMC and regular UART terminals.
>> +
>> +1. On the regular UART port start xmodem transfer of the u-boot.uart
>> +2. Using BMC terminal set the ARM-UART bootmode and reboot the EVM
>> +   BMC> bootmode #4
>> +   MBC> reboot
>> +3. When xmodem is complete you should see the u-boot starts on the UART port
>> +
>>   Load and Run U-Boot on keystone EVMs using CCS
>>   =========================================
>>
>>
>
> Could you please address the comments provided in V1 of your patch first?
> https://patchwork.ozlabs.org/patch/440322/
>
> I see my comments have not been responded to as to why the
> alternatives presented do not work.
>
> It is always a good practice to respond to review comments prior to
> posting a new revision and not just ignoring them.
>
> Sorry, I have to give a: Nak to this version of patch considering that
> there are still questions not addressed from V1.
>
Nishanth,

The purpose of the patch is provide a way to download to KS2 internal 
RAM and boot previously built u-boot.bin. But not to improve or change 
anything else.

V2 just addressed comments related to the atch itself, but not other 
comments those are not related to the purpose of the patch.

Regards,
-Vitaly