Tool/software: Linux
Hi
I am looking for help in trying to debug why I cannot get my root filesystem to mount.
I am using an am355x on the latest SDK on a board based on the BeagleBoneBlack
It is intended that this will be a small filesystem resident on a SPI NOR flash.
The chip we are using a N25Q256 with page size 256 Bytes, erase size 4 KiB, total 32 MiB.
It is partitioned within the device tree as:
&spi0 {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&spi0_pins>;
spi-flash@0 {
compatible = "micron,n25q256a","jedec,spi-nor";
spi-max-frequency = <48000000>;
status = "okay";
reg = <0>;
m25p,fast-read;
#address-cells = <1>;
#size-cells = <1>;
partition@0 {
label = "SPL";
reg = <0x00000000 0x00020000>;
};
partition@20000 {
label = "u-boot";
reg = <0x00020000 0x00066000>;
};
partition@86000 {
label = "dtb";
reg = <0x00086000 0x00010000>;
};
partition@96000 {
label = "kernel";
reg = <0x00960000 0x0050a000>;
};
partition@5a0000 {
label = "-";
reg = <0x005a0000 0x01a60000>;
};
};
};
on booting the kernel these appear as:
[ 1.094466] m25p80 spi1.0: n25q256a (32768 Kbytes) [ 1.098993] 5 ofpart partitions found on MTD device spi1.0 [ 1.104083] Creating 5 MTD partitions on "spi1.0": [ 1.108555] 0x000000000000-0x000000020000 : "SPL" [ 1.114522] 0x000000020000-0x000000086000 : "u-boot" [ 1.120532] 0x000000086000-0x000000096000 : "dtb" [ 1.126190] 0x000000960000-0x000000e6a000 : "kernel" [ 1.132166] 0x0000005a0000-0x000002000000 : "-"
I have used BitBake and the instructions in processors.wiki.ti.com/.../Processor_SDK_Building_The_SDK to create a ubifs and ubi
I modified the descriptors within my MACHINE config for these to try and match the chip we are using.
These modifications were:
MKUBIFS_ARGS = "-F -m 256 -e 126976 -c 110" UBINIZE_ARGS = "-m 256 -p 4KiB"
I then transfer the .ubi file via u-boot (sf erase and sd write) in to the intended location of the chip
- SPL, u-boot, kernel and devicetree are all loaded and run from SPI flash without problem
The rootfs however fails to mount, specifically failing to "attach" the mtd4:
[ 0.000000] Kernel command line: console=ttyO0,115200n8 noinitrd ip=off rw ubi.mtd=4,256 noinitrd rootfstype=ubifs m em=256M root=ubi0:rootfs rootwait=1 <snip> [ 1.607933] ubi0: attaching mtd4 [ 1.617855] ubi0 error: validate_ec_hdr: bad data offset 512, expected 320 [ 1.624236] ubi0 error: validate_ec_hdr: bad EC header [ 1.637806] Erase counter header dump: [ 1.641286] magic 0x55424923 [ 1.644762] version 1 [ 1.647511] ec 0 [ 1.667801] vid_hdr_offset 256 [ 1.670715] data_offset 512 [ 1.673627] image_seq 645878812 [ 1.677020] hdr_crc 0x63941dbf [ 1.687801] erase counter header hexdump: [ 1.691567] CPU: 0 PID: 1 Comm: swapper Not tainted 4.4.19-gdb0b54cdad #74 [ 1.707811] Hardware name: Generic AM33XX (Flattened Device Tree) [ 1.713466] Backtrace: [ 1.715779] [<c00134e4>] (dump_backtrace) from [<c00136e0>] (show_stack+0x18/0x1c) [ 1.737804] r7:00000000 r6:00000000 r5:cd824000 r4:cdd19340 [ 1.743107] [<c00136c8>] (show_stack) from [<c02b9848>] (dump_stack+0x24/0x28) [ 1.767829] [<c02b9824>] (dump_stack) from [<c0448640>] (validate_ec_hdr+0xc0/0x12c) [ 1.775023] [<c0448580>] (validate_ec_hdr) from [<c04492a4>] (ubi_io_read_ec_hdr+0x168/0x218) [ 1.797806] r7:cd824000 r6:55424923 r5:cdd19340 r4:00000000 [ 1.803097] [<c044913c>] (ubi_io_read_ec_hdr) from [<c044e388>] (ubi_attach+0x184/0x14b0) [ 1.817804] r10:cdd11a80 r9:c09a531c r8:00000000 r7:cd824000 r6:00000000 r5:cd824000 [ 1.825102] r4:00000000 [ 1.827465] [<c044e204>] (ubi_attach) from [<c0442dec>] (ubi_attach_mtd_dev+0x640/0xbf0) [ 1.857801] r10:fffff000 r9:00000140 r8:cdc73800 r7:cd824000 r6:00000000 r5:cdc73800 [ 1.865098] r4:00000001 [ 1.867463] [<c04427ac>] (ubi_attach_mtd_dev) from [<c08f67bc>] (ubi_init+0x1e4/0x26c) [ 1.887801] r10:fffff000 r9:c0865488 r8:c08654b4 r7:c090d680 r6:c090d684 r5:cdc73800 [ 1.895099] r4:00000000 [ 1.897462] [<c08f65d8>] (ubi_init) from [<c00096bc>] (do_one_initcall+0x98/0x1e4) [ 1.917805] r10:00000000 r9:c08d3600 r8:000000a9 r7:cdd19280 r6:c091ac60 r5:c08f65d8 [ 1.925103] r4:c091ac60 [ 1.927478] [<c0009624>] (do_one_initcall) from [<c08d3e80>] (kernel_init_freeable+0x138/0x1cc) [ 1.957802] r10:00000008 r9:c08d3600 r8:000000a9 r7:c0907834 r6:c0914120 r5:c0964d80 [ 1.965102] r4:c0964d80 [ 1.967472] [<c08d3d48>] (kernel_init_freeable) from [<c068002c>] (kernel_init+0x18/0xf4) [ 1.987801] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0680014 [ 1.995097] r4:c0964d80 [ 1.997461] [<c0680014>] (kernel_init) from [<c000fab8>] (ret_from_fork+0x14/0x3c) [ 2.027801] r5:c0680014 r4:00000000 [ 2.031133] ubi0 error: ubi_io_read_ec_hdr: validation failed for PEB 0 [ 2.037279] ubi0 error: ubi_attach_mtd_dev: failed to attach mtd4, error -22 [ 2.057817] UBI error: cannot attach mtd4 [ 2.061786] hctosys: unable to open rtc device (rtc0) [ 2.081261] vmmcsd_fixed: disabling [ 2.084658] ALSA device list: [ 2.087413] No soundcards found. [ 2.109328] UBIFS error (pid: 1): cannot open "ubi0:rootfs", error -19VFS: Cannot open root device "ubi0:rootfs" or unknown-block(0,0): error -19 [ 2.127837] Please append a correct "root=" boot option; here are the available partitions: [ 2.135613] 1f00 128 mtdblock0 (driver?) [ 2.158792] 1f01 408 mtdblock1 (driver?) [ 2.163487] 1f02 64 mtdblock2 (driver?) [ 2.177811] 1f03 5160 mtdblock3 (driver?) [ 2.182509] 1f04 27008 mtdblock4 (driver?) [ 2.187203] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) [ 2.194875] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
I have tried several variations of the bootargs without succees:
Including:
root=/dev/mtd4 root=/dev/mtdblock root=ubi0:rootfs
I would be grateful for any suggestions as to what I might be doing wrong.
Best regards,
Richard
