Hi, guys:
I'm not an expert so I can't figure out what is the magic in u-boot DCD table.
only I know is following this guide below, it tells me , just filling the excel and copy-past the value from the excel to my DCD table.
Now it seems a bit old, because 2014.10 u-boot writes 101 DCD items while 2009.08 u-boot just writes 83 items.
so I can't find how to match these DCD item not generated by i.Mx6DQSDL DDR3 Script Aid.
For example, 2009.08 u-boot write address 0x021b001c 7 times, once for "MMDC init", and 6 times for "Mode register writes".
2014.10 u-boot write 0x021b001c for 11 times, once for "MMDC init", and 10 times for "Mode register writes", I guess.
and 2014.10 u-boot also write address which not include in 2009.08 version:
* 0x020e0590 -> Unknown usage, the value is the same as 2009.08 default value.
* 0x020e0598 -> Unknown usage, the value is the same as 2009.08 default value.
* 0x021b4800 -> Unknown usage.
* 0x020c4068 -> set the default clock gate to save power
* 0x020c406c -> set the default clock gate to save power
* 0x020c4070 -> set the default clock gate to save power
* 0x020c4074 -> set the default clock gate to save power
* 0x020c4078 -> set the default clock gate to save power
* 0x020c407c -> set the default clock gate to save power
* 0x020c4080 -> set the default clock gate to save power
* 0x020e0010 -> enable AXI cache for VDOA/VPU/IPU
* 0x020e0018 -> set IPU AXI-id0 Qos=0xf(bypass) AXI-id1 Qos=0x7
* 0x020e001c -> set IPU AXI-id0 Qos=0xf(bypass) AXI-id1 Qos=0x7
* 0x020c4060 -> sets CCM_CCOSR register "CKO1" at ahb_clk_root/8 = 132/8 = 16.5 MHz
Does some body know how to match 2009.08 u-boot DCD items to 2014.10 u-boot correctly?
any suggestion will be appreciated, thanks.
Wally
Solved! Go to Solution.
Hi Wally
uboot 2014 is quite different from 2009.08, as it uses
device tree concept (UBootFdtInfo < U-Boot < DENX).
Seems there is no need to modify uboot 2009.08 DCD items,
as actually differencies which you mentioned are contained
in another uboot 2009.08 file: lowlevel_init.S.
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hi Wally
uboot 2014 is quite different from 2009.08, as it uses
device tree concept (UBootFdtInfo < U-Boot < DENX).
Seems there is no need to modify uboot 2009.08 DCD items,
as actually differencies which you mentioned are contained
in another uboot 2009.08 file: lowlevel_init.S.
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hi, igorpadykov:
Thanks for your answer. :smileygrin: that's really help. my boss choose different DDR Ram to cost down the product.
so I need to replace the DTD items to get correct DDR timing.
I take a look for u-boot-2009.08/board/freescale/mx6q_sabresd/lowlevel_init.S.
now is what I found:
2014.10 u-boot 2009.08
* 0x020c4068 -> 0x00C03F3F * 0x020c4068 -> 0x00C0003F different value
* 0x020c406c -> 0x0030FC03 * 0x020c406c -> 0x0030FC00 different value
* 0x020c4070 -> 0x0FFFC000 * 0x020c4070 -> 0x0FFFC000 matched
* 0x020c4074 -> 0x3FF00000 * 0x020c4074 -> 0x3FF00000 matched
* 0x020c4078 -> 0x00FFF300 * 0x020c4078 -> 0x00FFF300 matched
* 0x020c407c -> 0x0F0000C3 * 0x020c407c -> 0x0F0000C3 matched
* 0x020c4080 -> 0x000003FF * 0x020c4080 -> 0x000003FC different value
* 0x020c4060 -> 0x000000FB * 0x020c4060 -> 0x000A0001 2014.10 seems enable CKO1.
only one thing now I can't match:
* 0x021b001c -> 0x04088032 * 0x021b001c -> 0x04088032 matched
* 0x021b001c -> 0x0408803A * where is it ?
* 0x021b001c -> 0x00008033 * 0x021b001c -> 0x00008033 matched
* 0x021b001c -> 0x0000803B * where is it ?
* 0x021b001c -> 0x00428031 * 0x021b001c -> 0x00048031 matched
* 0x021b001c -> 0x00428039 * where is it ?
* 0x021b001c -> 0x19308030 * 0x021b001c -> 0x09408030 different value
* 0x021b001c -> 0x19308038 * where is it ?
* 0x021b001c -> 0x04008040 * 0x021b001c -> 0x04008040 matched
* 0x021b001c -> 0x04008048 * where is it ?
there is 0x021B0004 should set to 0x00025576 after setting above 0x021b001c register. but can't find it on 2014.10 u-boot.
could you help me with these 5 register value (mark as * where is it ? ).
Wally
Sorry, i.Mx6DQSDL DDR3 Script Aid already generate 10 times of 0x021b001c.
5 times for MMDC CS0 and 5 times for CS1.
2009.08 only write DCD items for CS0.