Thanks for the reply. I will do some more testing and get back to you.
Posts by camforrest
-
-
Does anyone have experience using DDR from the M7 core?
We would like to use DDR (with caching enabled) for extra data space - which we have done, and It sometimes works, but often crashes.
Picocoremx8mp.dtsi has this comment and #if :
Can anyone clarify why running from DDR is not supported? The NXP evk dts (imx8mp-evk-rpmsg.dts) has this section enabled.
We have enabled this section of the device tree (removing the #if 0).
We are still using MIMX8ML8xxxxx_cm7_ram.ld which has been working fine, but have modified to add a new m_data3 section, which we would like to have caching enabled for performance. So we have defined __CACHE_REGION_START/SIZE to match this section.
Display MoreCode- MEMORY
- {
- m_interrupts (RX) : ORIGIN = 0x00000000, LENGTH = 0x00000400
- m_text (RX) : ORIGIN = 0x00000400, LENGTH = 0x0001FC00
- m_data (RW) : ORIGIN = 0x20000000, LENGTH = 0x00020000
- m_data2 (RW) : ORIGIN = 0x80000000, LENGTH = 0x00800000
- m_data3 (RW) : ORIGIN = 0x80800000, LENGTH = 0x00800000
- }
- .externalcacheablenoinit (NOLOAD) :
- {
- __externalcacheablenoinit_start__ = .;
- *(ExternalCacheableNoInit)
- . = ALIGN(4);
- __externalcacheablenoinit_end__ = .;
- } > m_data3
- __CACHE_REGION_START = ORIGIN(m_data3);
- __CACHE_REGION_SIZE = LENGTH(m_data3);
The init code in board.c applies the following DDR settings:
Any clues, or reports if others have this working would be much appreciated!
-
We are also looking into CPU temperature. Currently with low load, the core is reporting around 55degs, in ambient of around 25degs.
We only have a heatspreader (not a heatsink). NXP AN13054 leads me to expect more like 40degs.
So far I have tried disabling 3 of the 4 A53 cores (in uboot, set "extra" to "maxcpus=1"), and also using the LCD enabled device tree vs no LCD. Neither had a significant impact on temperature.
It would be great if others would share their cooling setup and temperatures etc. -
Hi,
While I wait for my evaluation board to arrive I'm looking into the docs and VM. I notice there is not (yet) a freertos release for the mx8mp (only for the mx8mm).
Do you have any information on when a release might be available, and/or any experience on modifying the mm release to run the examples (or even a helloworld)?Thanks!
Cam
