Fixes#147
* Can vary tick rate from 100Hz via configTICK_RATE_HZ. Note that the
SDK binary libraries are hard-coded to assume the tick rate is 100Hz,
so changing the tick rate may have unexpected consequences for lower
layer WiFi behaviour (such as certain kinds of timeouts happening
faster/slower.)
* Setting configCPU_CLOCK_HZ to 160MHz means ESP will set 160MHz during
initialisation. Only 80MHz and 160MHz are supported.
* Timing of tasks is no longer affected by current CPU freq (whether set
via configCPU_CLOCK_HZ or via sdk_system_update_cpu_freq().)
Previously doubling the CPU frequency would double the tick rate.
RTOS Timer tick handler is now the same as any other ISR.
This causes a few subtle behaviour changes that seem OK but are worth noting:
* RTOS tick handler sdk__xt_timer_int() is now called from one stack
frame deeper (inside _xt_isr_handler()), whereas before it was called
from the level above in UserHandleInterrupt. I can't see any way that
the extra ~40 bytes of stack use here hurt, though.
* sdk__xt_timer_int() was previous called after all other interrupts
flagged in the handler, now it's called before the TIMER FRC1 & FRC2
handlers. The tick handler doesn't appear to do anything particularly
timing intensive, though.
* GPIO interrupt (value 3) is now lower priority than the SPI
interrupt (value 2), whereas before it would have been called before
SPI if both interrupts triggered at once.
Prerequisite for calling Cache_Read_Disable() for OTA updates.
Massive thanks due to @foogod and their xtobjdis tool, creating the call
graph of where the wDev_ProcessFiq touched (including in newlib, etc.)
would have otherwise been very painful:
https://bitbucket.org/foogod/xtobjdis
At the moment these are almost bit-for-bit copies of the vector
behaviour in the RTOS SDK, but hopefully that will start to change.
Progress towards #2
Closes#7.
It'd be nice to change the linker script so .text is always linked to
IROM instead of needing to objcopy each compiled file. The sticking
point for this is libgcc & libhal, which have symbols in .text that need
to be loaded to IRAM.
* This fixes the problem of axTLS symbols hmac_md5/hmac_sha1 having same
name as symbols in libwpa (which have incompatible signatures)
* Also allows for easier identification and piece-by-piece removal of
binary functions.
* Some libc symbols are not renamed, list is in lib/symbols_norename.txt
