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| author | Gregory Nutt <gnutt@nuttx.org> | 2015-03-29 13:09:22 -0600 |
|---|---|---|
| committer | Gregory Nutt <gnutt@nuttx.org> | 2015-03-29 13:09:22 -0600 |
| commit | 72adecb9057d7015c5d1729ec3752926284bab8c (patch) | |
| tree | 32d43aee83799c9f1ad28a9a1c18bde492c553d7 /nuttx/configs | |
| parent | 6c2f4007dc9fc482d650a956ef13959f502d327b (diff) | |
| download | px4-nuttx-72adecb9057d7015c5d1729ec3752926284bab8c.tar.gz px4-nuttx-72adecb9057d7015c5d1729ec3752926284bab8c.tar.bz2 px4-nuttx-72adecb9057d7015c5d1729ec3752926284bab8c.zip | |
SAMV7/Cortex-M7: Add support for write through D-Cache. SAMV7 Ethernet look like it needs this
Diffstat (limited to 'nuttx/configs')
| -rw-r--r-- | nuttx/configs/samv71-xult/README.txt | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/nuttx/configs/samv71-xult/README.txt b/nuttx/configs/samv71-xult/README.txt index ba23c160e..0efaff880 100644 --- a/nuttx/configs/samv71-xult/README.txt +++ b/nuttx/configs/samv71-xult/README.txt @@ -105,6 +105,12 @@ The BASIC nsh configuration is fully function (as desribed below under At -O2, many packets can be exchanged but eventually there is a hardfault, presumably because of a misdirected DMA. + I have no hard evidence, but I believe that the nature of the problem + related to fact that each descriptor in the arrays are 8-bytes each, + but cache operations are performed on 32-byte memory chunks. So it is + impossible to clean or invalidate a single descriptor without also + cleaning or invalidaing adjacent descriptors. + 7. The USBHS device controller driver (DCD) is complete but non-functional. At this point, work has stopped because I am stuck. The problem is that bus events are not occurring: Nothing is detected by the USBHS when the @@ -117,9 +123,7 @@ The BASIC nsh configuration is fully function (as desribed below under sample code and study of the data sheet, but I have not found the key to solving this. - - I need to try this as -O2 optimization as well. - -Serial Console ++nmnmSerial Console ============== The SAMV71-XULT has no on-board RS-232 drivers so it will be necessary to @@ -767,6 +771,12 @@ NOTES: System Type -> Toolchain: CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : GNU ARM EABI toolchain + NOTE: As of this writing, there are issues with using this tool at + the -Os level of optimization. This has not been proven to be a + compiler issue (as least not one that might not be fixed with a + well placed volatile qualifier). However, in any event, it is + recommend that you use not more that -O2 optimization. + Configuration sub-directories ----------------------------- |