SCSI read(10) reads out weird values- USB pendrive - embedded

I am implementing USB as a host using OHCI to read the files stored in the Flashdrive. To read I implement the read(10) command in SCSI. The Logical Block address being the sector number. The following is an image of the command I send for read(10) to read LBA 0x0000-
http://i.imgur.com/ky4FHlm.png
I read 512bytes(size of one sector or 1 LBA)and the following is the output that i get for LBA 0x0000-
http://imgur.com/jL6OEjE
The bytes in the above image are not present any where on the pendrive, I checked that using HXD. Now, for testing I filled the pendrive to full capacity. If I read any other LBA, other than 0x0000, then I always get 512 bytes of 0x00.
Could anyone please tell me what the problem could be?
Am I supposed to execute some other command before I do a read(10) so that the USB sends me the right data maybe?
From my understanding I have put DPO, FUA and FUA_NV=0 and also RDPROTECT=2

Related

How to erase msp430f2619 flash using bsl?

I want to do mass erase on my msp430f2619 using bsl. I use software jump in my code to invoke bsl. I send 0x80, get 0x90 from BSL(ack). Then i send mass erase command and get 0x90 again. Then i power off my device, then i power on the device, then i send 0x80 and get 0x90, that means there was no mass erase operation.
Read command is not working too. I send password (0xFF 32 times), after that send rx command, then i get few coorect bytes, and then infinite raw of 0xff.
I think i miised something before jump to bsl, please give an example code, or step by step instruction on how to make software jump to bsl and make it work correctly.
If you are sending 0x80 only, then get back 0x90, this confirms you have entered into the BSL since this completes the required synchronization sequence (see section 2.1 of this document). You should not require the "RX password" command since the "Mass erase" command is not protected.
The next sequence after the synchronization is to send the desired command, which should be the "Mass erase". There is a format to each of the BSL commands called the data frame. You want to send the following data frame: eight mandatory bytes (note two dummy bytes), and two checksum bytes. Note the "Mass erase" command does not contain data bytes, but you need to calculate the checksum bytes. Here are the bytes to be sent to perform the mass erase:
80 18 04 04 dd dd 06 A5 CL CH
Where: dd = dummy bytes (any value accepted), CL = Checksum low, CH = Checksum high
After sending this data frame then you should receive the ACK (0x90) byte. Then power off the device.

Why received ZFS dataset uses less space than original?

I have a dataset on the server1 that I want to back up to the second server2.
Server1 (original):
zfs list -o name,used,avail,refer,creation,usedds,usedsnap,origin,compression,compressratio,refcompressratio,mounted,atime,lused storage/iscsi/webhost-old produces:
NAME USED AVAIL REFER CREATION USEDDS USEDSNAP ORIGIN COMPRESS RATIO REFRATIO MOUNTED ATIME LUSED
storage/iscsi/webhost-old 67,8G 1,87T 67,8G Út kvě 31 6:54 2016 67,8G 16K - lz4 1.00x 1.00x - - 67,4G
Sending volume to the 2nd server:
zfs send storage/iscsi/webhost-old | pv | ssh -c arcfour,aes128-gcm#openssh.com root#10.0.0.2 zfs receive -Fduv pool/bkp-storage
received 69,6GB stream in 378 seconds (189MB/sec)
Server2 zfs list produces:
NAME USED AVAIL REFER CREATION USEDDS USEDSNAP ORIGIN COMPRESS RATIO REFRATIO MOUNTED ATIME LUSED
pool/bkp-storage/iscsi/webhost-old 36,1G 3,01T 36,1G Pá pro 29 10:25 2017 36,1G 0 - lz4 1.15x 1.15x - - 28,4G
Why is there such a difference in sizes? Thanks.
From what you posted, I noticed 3 things that seemed odd:
the compressratio is 1.15x on system 2, but 1.00x on system 1
on system 2, used is 1.27x higher than logicalused
the logicalused and the number zfs receive report are ~2.3x higher on system 1 than system 2
These terms are all defined in the man page, but are still confusing to reverse-engineer explanations for in practice.
(1) could happen if you enabled compression on the source dataset after you wrote all the data to it, since ZFS doesn't rewrite the data to compress it when you enable that setting. The data sent by zfs send is uncompressed unless you use -c, but system 2 will try to compress it as it runs zfs receive if the setting is enabled on the destination dataset. If both system 1 and system 2 had the same compression settings before the data was written, they would have the same compressratio as well.
(2) can happen due to metadata written along with your data, but in this case it's too high for "normal" metadata, which accounts for 1-2% of most pools. It's probably caused by a pool-wide setting, like configuring RAID-Z, or a weird combination of striping and mirroring (like 4 stripes, but with one of them being a mirror).
For (3), I re-read the man page to try to figure it out:
logicalused
The amount of space that is "logically" consumed by this dataset and
all its descendents. See the used property. The logical space
ignores the effect of the compression and copies properties, giving a
quantity closer to the amount of data that applications see.
If you were sending a dataset (instead of a single iSCSI volume) and the send size matched system 2's logicalused value (instead of system 1's), I would guess you forgot to send some child datasets (i.e. by using zfs send -R). However, neither of those are true in this case.
I had to do some additional digging -- this blog post from 2005 might contain the explanation. If system 1 didn't have compression enabled when the data was written (like I guessed above for (1)), the function responsible for not writing zeroed-out blocks (zio_compress_data) would not be run, so you probably have a bunch of empty blocks written to disk, and accounted for in the logicalused size. However, since lz4 is configured on system 2, it would run there, and those blocks would not be counted.

required size of a configuration file for a HX1K (in "SPI slave" mode)

I am reworking the programmer for the Olimex iCE40HX1K board (targetted towards a STM32F103 ma) where I also would like to implement the "SPI Slave" mode to configure an image directly into RAM without using the serial flash.
Looking at the Lattice "programming and Configuration guide" (page 11), it is noted in table 8 that a EPROM for a ICE40-LP/LX1K must be at least 34112 bytes. (which -I guess- means that the configuration-files can be up to that size).
However, all images I have (sofar) created with the icestorm tools are 32220 octets.
I am a bit puzzled here.
Can somebody explain the difference between these two figures?
Does the HX1K need a configuration-file of 32220 or 34112 bytes?
I don't know how Lattice arrived at this number. A complete HX1K bin file with BRAM initialization but without comment and without multiboot header is 32220 bytes in size. The (optional) multiboot header would add another 160 bytes (32220 + 160 = 32380). The lattice tools usually add about 80 bytes to the comment field (32220 + 80 = 32300). Whatever I do, all numbers I have are more than 1000 short of 34112.
I don't know if there is a maximum length for the comment. Maybe there is and 34112 is the size of a bit stream with a comment of maximum length?
34112 - 32220 = 1892. Maybe someone decided to add 8kB (8192 bytes) just in case, but that person accidentally swapped the first two digits? Idk..
If you don't care about comments or multiboot headers, then iCE40 1K bit-streams have a fixed size, and that size is 32220 bytes.

Binary, produced by MSP430GCC, has strange start address for text segment

After compiling an exemplary C program with msp430-gcc (LTS 20120406 unpatched) for the MSPG2211 I got the following output using the readelf command:
section header
program header
The address space of the MSPG2211 microcontroller is structured as follows:
0x0000 - 0x01FF - Peripherals
0x0200 - 0x027F - RAM
0x1000 - 0x10FF - Flash (information memory)
0x1100 - 0xF7FF - ???
0xF800 - 0xFFFF - Flash (code memory + interrupt vectors)
The text section shown in the section header starts at 0xF800 which is the first address of the code memory.
The text segment, including only the text section, is bigger than the text section and starts already at 0xF76C.
As I understood, the loadable segments gets loaded to the shown physical addresses for program execution.
So why the start address of the text segment lies within an undefined memory region?
Some of the names sections (such as .text) contain data that is actually loaded into the MCU.
The ELF program headers, however, contain only metadata; their address does not matter.

Remote Proc fails to load FreeRTOS Elf

I am using this port of FreeRTOS and I am loading it onto the Cortex-M3 within an OMAP4430. This works fine using the remote proc framework and I am able to use RPMsg to communicate with it.
Sometimes, however, rproc fails to load the elf and gives the following error:
rproc remoteproc1: bad phdr da 0x0 mem 0x10310
rproc remoteproc1: Failed to load program segments: -22
rproc remoteproc1: rproc_boot() failed -22
This seems to happen when the size of the elf file gets too large: this happens when the size is 377331 bytes but does not happen when I simply remove a bunch of print statements and bring the size down to 342563 bytes.
I have tracked the error message down to this piece of code: http://lxr.free-electrons.com/source/drivers/remoteproc/remoteproc_elf_loader.c?v=3.9#L188. It seems that rproc_da_to_va is unable to find a segment in memory large enough to fit the ELF.
How can I make sure that there is enough memory for the size of my ELF? Can I tell the kernel that I specifically want a certain region preallocated for this kind of thing? Is there some way to ensure that this part of my ELF remains small?
Thanks!
Make sure that the FreeRTOS configuration constants configTEXT_SIZE and configDATA_SIZE agree with the amounts demanded by your linker script. For example, if your linker script contains
MEMORY
{
TEXT (rwx) : ORIGIN = 0x00000000, LENGTH = 1M
DATA (rwx) : ORIGIN = 0x80000000, LENGTH = 1M
}
then you should set configTEXT_SIZE and configDATA_SIZE to 0x100000.