Mity CPU Platforms » MityDSP-L138 (ARM9 Based Platforms)

01/30/2015

JM 10:35 PM PCB Development: RE: MityARM-1808F SATA connection problem

The SW developer told me the kernel version is 2.6.34
Does that affect the quality of link? Jun Mo

01/23/2015

SN 03:21 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

Hi mike
your are rigth. I tried it before the
map= (int *)(mmap(0,MAPPED_SIZE,PROT_READ|PROT_WRITE,MAP_SHARED,_fdmem,DDR_RAM_PHYS));
and forgot to correct it back.. Its working now, thanks alot.. stefan nielsen

01/22/2015

MW 07:32 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

No you don't need ot use SetSharedMemCfg() or SetPoolCfg() if you are not using the tcDspInbound and tcDspOutbound message passing frameworks.
If you look at the dspapp.cpp file in the MDK, you will see the following parameters: Michael Williamson

SN 03:57 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

Hi
do i need to use
int tcDspApp::SetSharedMemCfg(tsSharedMemCfg* pConfig)
or
int tcDspApp::SetPoolCfg(uint32_t anNumBufPools, uint32_t *apBufSizes,
uint32_t *apNumBuf, bool abExactMatch)
to use the Iram at 0... stefan nielsen

SN 01:59 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

Hi thanks for the help, I still got some problems with reading on the ARM.
ARM code: stefan nielsen

01/20/2015

JC 09:31 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

You may find this post helpful for transmitting non-string data using dsplink. https://support.criticallink.com/redmine/boards/10/topics/4178?r=4179#message-4179
Note that the tsData::data_ptr requires tcDspApp::ReadMemory() on the AR... Jonathan Cormier

MW 09:18 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

DSP code is OK, though if you have the caches enabled for the regions of SRAM or RAM you may need to add a cache write back call to ensure the data is moved to external memory for the ARM to pick up.
-Mike Michael Williamson

SN 09:05 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

Hi thanks for the quick reply. I found some stuff of how to do it on the ARM side, following the example you pointed out. On the DSP is it okay to write to memory as showed above ?
stefan nielsen

MW 07:33 AM Software Development: RE: Write to SharedMem from DSP and read it from ARM

The linux OS uses virtual memory addresses. You can't access RAM by physical address in the normal case.
You need to use /dev/mem and mmap in the memory you want to access (though it will not be cacheable with this technique). See t... Michael Williamson

SN 03:25 AM Software Development: Write to SharedMem from DSP and read it from ARM

Hi im trying to write to some shared memory from the DSP and read it back from the ARM. Ive expanded the HelloWorldDSP project, so memory is mapped as in that project. I tried on 4 different memory areas.
DSP code: stefan nielsen

01/19/2015

MW 07:08 AM PCB Development: RE: MityARM-1808F SATA connection problem

What version of the kernel are you using? Michael Williamson

01/18/2015

JM 11:30 AM PCB Development: RE: MityARM-1808F SATA connection problem

From the kernel boot message, occasionally it failed to link to 3G speed, it linked up to 1.5G, but most of the time if link to 3G failed, it failed totally at all. Even though it linked up at 1.5G, it failed to mount the file system.
... Jun Mo

01/16/2015

MW 07:24 AM PCB Development: RE: MityARM-1808F SATA connection problem

I am fairly certain that the lengths on the module for the SATA lines are matched. I will check with our PCB designer.
Do your boards ever negotiate to SATA-I speeds instead of SATA-II speeds? You should be able to see the negotiate... Michael Williamson