Merge branch 'bugfix/longer-osc-stab' into 'main'

Add hack for raising oscillator startup delay

See merge request !10

.gitlab-ci.yml

@@ -16,6 +16,8 @@ build micropython firmware:
     - make -C micropython/mpy/ports/rp2 submodules
     # HACK: patch a bug in Pico SDK (https://github.com/raspberrypi/pico-sdk/issues/737)
     - patch -p1 --forward -i micropython/timer-bug.patch
+    # HACK: wait longer for oscillator initialization
+    - patch -p1 --forward -i micropython/xosc-wait.patch
     - make -C micropython/mpy/mpy-cross -j $(nproc)
     - make -C micropython/mpy/ports/rp2 clean
     - make -C micropython/mpy/ports/rp2 USER_C_MODULES=$(pwd)/micropython/modules/micropython.cmake -j $(nproc)

micropython/xosc-wait.patch

+--- a/micropython/mpy/lib/pico-sdk/src/rp2_common/hardware_xosc/include/hardware/xosc.h
++++ b/micropython/mpy/lib/pico-sdk/src/rp2_common/hardware_xosc/include/hardware/xosc.h
+@@ -14,9 +14,9 @@
+ // Allow lengthening startup delay to accommodate slow-starting oscillators
+ 
+ // PICO_CONFIG: PICO_XOSC_STARTUP_DELAY_MULTIPLIER, Multiplier to lengthen xosc startup delay to accommodate slow-starting oscillators, type=int, min=1, default=1, group=hardware_xosc
+-#ifndef PICO_XOSC_STARTUP_DELAY_MULTIPLIER
+-#define PICO_XOSC_STARTUP_DELAY_MULTIPLIER 1
+-#endif
++// HACK: raised here to work around flash chip issues
++#undef  PICO_XOSC_STARTUP_DELAY_MULTIPLIER
++#define PICO_XOSC_STARTUP_DELAY_MULTIPLIER 100
+ 
+ 
+ #ifdef __cplusplus