[A20 with eMMC on SD2]

Of course my question came just before I had some progress. I see /dev/mmcblk1 now! I just used some wrong diskimage (I think, I'll have to check). It is not very stable now, maybe due wrong content or timing. Another thing I have to find out.

But you may ignore my questions for now. Sorry for the noise.

 

An the next step will be difficult. I want to boot from the eMMC. No idea whether this is really possible but that's what I really want to do. There is a possibility that I'll ask questions about this. I'll try to be more thorough then.

 

I forgot to mention:

Using the fex file I misuse a GPIO pin to simulate an SD DETECT line. That's how I can at least boot Linux and it gives me some possibility to check what's happening.

 

Guus

 

[A20 with eMMC on SD2]

First a very big "Thank you", Igor. You create wonderful images.

 

But now the problem. I want to boot the A20 from an eMMC Flash. I use a HAOYU New MarsBoard A20 Dev Board. The reason: the CM-A10/A20 PCB has a footprint for an eMMC. So the 8GB NAND was removed and replaced by a 2GB eMMC.

Then I took the Pecovnik Olimex Lime2 Jessie 3.4.108 image and added the fex file from the MarsBoard SD image. After a fex2bin the MarsBoard bootet from SD0. Life was beautiful.

 

The problems start if I wanted to contact the eMMC. I changed "[nand_para] nand_used" to 0. And I changed "[mmc2_para] sdc_used" to 1.

Then the kernel gets in serious problems:

<6>[mmc-msg] sdc2 set ios: clk 52000000Hz bm PP pm ON vdd 3.3V width 1 timing MMC-HS(SDR20) dt B
<6>[mmc-msg] sdc2 set round clock 46153846, src 600000000
<6>[mmc-msg] sdc2 set ios: clk 52000000Hz bm PP pm ON vdd 3.3V width 8 timing MMC-HS(SDR20) dt B
<3>[mmc-err] smc 2 err, cmd 8,  EBE
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>[mmc-err] sdc 2 send stop command failed
<6>[mmc-msg] sdc2 set ios: clk 52000000Hz bm PP pm ON vdd 3.3V width 4 timing MMC-HS(SDR20) dt B
<6>mmc1: new high speed MMC card at address 0001
<6>mmcblk1: mmc1:0001 MMC02G 1.78 GiB
<6>mmcblk1boot0: mmc1:0001 MMC02G partition 1 1.00 MiB
<6>mmcblk1boot1: mmc1:0001 MMC02G partition 2 1.00 MiB
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
Dev mmcblk1: unable to read RDB block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>[mmc-err] smc 2 err, cmd 18,  RTO
<3>[mmc-err] In data read operation
<6>[mmc-msg] found data error, need to send stop command
<3>mmcblk1: timed out sending r/w cmd command, card status 0x900
<3>mmcblk1: not retrying timeout
<3>end_request: I/O error, dev mmcblk1, sector 0
<3>Buffer I/O error on device mmcblk1, logical block 0
<3>Dev Sunxi softw311 mmcblk1 header: error reading sector 0
<1>Unable to handle kernel NULL pointer dereference at virtual address 00000000
<1>pgd = c0004000
<1>[00000000] *pgd=00000000
<0>Internal error: Oops: 17 [#1] PREEMPT SMP ARM
<d>Modules linked in: cpufreq_userspace 8188eu spidev a20_tp 8021q garp stp llc hidp rfcomm hci_uart bluetooth
CPU: 1    Not tainted  (3.4.108-lime #14)
PC is at put_page+0x0/0x48
LR is at sunxi_nand311_partition+0x84/0x1f4
pc : [<c00b668c>]    lr : [<c03dd618>]    psr: 600d0013
sp : ef05bc68  ip : 0007ffff  fp : 00000000
r10: 00000000  r9 : 00000000  r8 : 00000000
r7 : 00000000  r6 : ee208000  r5 : 00000001  r4 : 00000000
r3 : c0a26554  r2 : c0a26554  r1 : 600d0093  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 6e72006a  DAC: 00000015
 

I must say that it is not 100% sure that soldering was performed correctly: though the person doing it is very capable soldering a BGA by hand is "blind work". OTOH the kernel says "mmcblk1: mmc1:0001 MMC02G 1.78 GiB" which indicates that the eMMC was seen.

The line with "LR is at sunxi_nand311_partition" indicates to me that the sunxi nand driver may cause problems so my thought was to build the kernel with the CONFIG_SUNXI_NAND_PARTITION=n and CONFIG_SUNXI_NAND=n.

Unfortunately this seems to cause even more problems: even U-Boot does not work anymore. The Olimex Lime2 (with different boot.scr and script.bin) has no problems with the same image.

 

My questions:

* Has anybody tried booting an A20 from SD2.

* Has anybody tried accessing an eMMC from an A20?

 

Thanks in advance,

Guus