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[Bug 1809291] Re: SD Card not working in Ubuntu 18.10 (CMD 2, 3 timeout)
From: |
The Lemon Man |
Subject: |
[Bug 1809291] Re: SD Card not working in Ubuntu 18.10 (CMD 2, 3 timeout). The device worked fine in Ubuntu 18.04 and earlier versions but not in Ubuntu 18.10 |
Date: |
Thu, 12 Nov 2020 17:29:38 -0000 |
The new code in Qemu is correct, the real problem is that the code [1] is
trying to negotiate an invalid working voltage with CMD41.
The SD specification marks the first 15 bits as reserved (except for the 7th,
that's the dual-voltage flag) meaning that compliant cards will timeout as well.
If you look closer at the source code you can see that this problem's
been patched by replacing the invalid argument 0x1 with a more
reasonable 0xFFFF, barely enough to work in the 2.7V range.
[1] https://eecs.wsu.edu/~cs460/samples/LAB5pre/step3/sdc.c
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https://bugs.launchpad.net/bugs/1809291
Title:
SD Card not working in Ubuntu 18.10 (CMD 2,3 timeout). The device
worked fine in Ubuntu 18.04 and earlier versions but not in Ubuntu
18.10
Status in QEMU:
Confirmed
Bug description:
ARM PL181 MMC card no longer working in qemu-system-arm in Ubuntu 18.10
The MMC driver code worked fine in Ubuntu 15.10 to 18.04.
The command to run qemu-system-arm is
qemu-system-arm -M versatilepb -m 256M -sd sdimage -kernel t.bin
-serial mon:stdio
During SDC initialization, SDC commands 2, 3, 9, 13, 7, 16 all timeout,
which cause subsequent read/write commands 17/24 to fail also.
Tried both ARM versatilepb and realview-pb-a8, realview-pbx-a9 boards:
all the same.
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- [Bug 1809291] Re: SD Card not working in Ubuntu 18.10 (CMD 2, 3 timeout). The device worked fine in Ubuntu 18.04 and earlier versions but not in Ubuntu 18.10,
The Lemon Man <=