Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

stm32f7: DTCM included in sram0 #15909

Closed
matthew-koch opened this issue May 5, 2019 · 0 comments · Fixed by #15910
Closed

stm32f7: DTCM included in sram0 #15909

matthew-koch opened this issue May 5, 2019 · 0 comments · Fixed by #15910
Assignees
@erwango
Labels
area: Devicetree bug The issue is a bug, or the PR is fixing a bug platform: STM32 ST Micro STM32 priority: low Low impact/importance bug

Comments

@matthew-koch
Copy link
Contributor

Describe the bug
The SRAM base address and sizes for the STM32F7 dts configs includes DTCM memory @ 0x20000000, but TCM is a different beast and probably shouldn't be lumped with in with SRAM.

Expected behavior
DTCM and ITCM require some special handling and have some special features. For the time being, use only SRAM1 and SRAM2.

A feature enhancement would be to enable ITCM and DTCM and make use of them.

Impact
May create subtle issues with DMA (LTDC, Ethernet, others fight with CPU). There may be issues with memory blocks that cross the DTCM/SRAM address.

Environment (please complete the following information):
STM32F7-based boards, at least.

Additional context
ST AN4667:

https://www.st.com/content/ccc/resource/technical/document/application_note/0e/53/06/68/ef/2f/4a/cd/DM00169764.pdf/files/DM00169764.pdf/jcr:content/translations/en.DM00169764.pdf
@matthew-koch matthew-koch added the bug The issue is a bug, or the PR is fixing a bug label May 5, 2019
@matthew-koch matthew-koch mentioned this issue May 5, 2019
Merged
matthew-koch added a commit to matthew-koch/zephyr that referenced this issue May 5, 2019
@matthew-koch
dts: stm32f7: Remove DTCM from sram0
9d318e1 
DTCM probably shouldn't be lumped with SRAM.

Fixes: zephyrproject-rtos#15909

Signed-off-by: Matthew Koch <koch.matthew@gmail.com>
@carlescufi carlescufi added platform: STM32 ST Micro STM32 area: Devicetree priority: low Low impact/importance bug labels May 14, 2019
matthew-koch added a commit to matthew-koch/zephyr that referenced this issue May 15, 2019
@matthew-koch
dts: stm32f7: Remove DTCM from sram0
f2cbba5 
DTCM probably shouldn't be lumped with SRAM.

Fixes: zephyrproject-rtos#15909

Signed-off-by: Matthew Koch <koch.matthew@gmail.com>
nashif pushed a commit that referenced this issue May 28, 2019
@matthew-koch @nashif
dts: stm32f7: Remove DTCM from sram0
d94c0d3 
DTCM probably shouldn't be lumped with SRAM.

Fixes: #15909

Signed-off-by: Matthew Koch <koch.matthew@gmail.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees

@erwango erwango

Labels
area: Devicetree bug The issue is a bug, or the PR is fixing a bug platform: STM32 ST Micro STM32 priority: low Low impact/importance bug
Projects
None yet
Milestone
No milestone
Development

Successfully merging a pull request may close this issue.

dts: stm32f7: Remove DTCM from sram0 matthew-koch/zephyr
3 participants
@carlescufi @erwango @matthew-koch