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atmel-samd: Enable -Os for SAMD51 and update neopixel accordingly.

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This commit is contained in:
Scott Shawcroft 2017-11-06 16:28:52 -08:00
parent e2867eb4e9
commit a8ee0012d7
2 changed files with 16 additions and 17 deletions
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2
ports/atmel-samd/Makefile
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@ -85,7 +85,7 @@ CFLAGS = -Os -DNDEBUG
endif
ifeq ($(CHIP_FAMILY), samd51)
CFLAGS = -O2 -DNDEBUG
CFLAGS = -Os -DNDEBUG
endif
#Debugging/Optimization

31
ports/atmel-samd/common-hal/neopixel_write/__init__.c
View File

@ -32,18 +32,17 @@
#include "tick.h"
#ifdef SAMD51
static inline void delay_cycles(uint8_t cycles) {
uint32_t start = SysTick->VAL;
uint32_t stop = start - cycles;
if (start < cycles) {
stop = 0xffffff + start - cycles;
while (SysTick->VAL < start || SysTick->VAL > stop) {}
} else {
// Make sure the systick value is between start and stop in case it
// wraps around before we read its value less than stop.
while (SysTick->VAL > stop && SysTick->VAL <= start) {}
// This magical macro makes sure the delay isn't optimized out and is the
// minimal three instructions.
#define delay_cycles(cycles) \
{ \
uint32_t t; \
asm volatile ( \
"movs %[t], %[c]\n\t" \
"loop%=:\n\t" \
"subs %[t], #1\n\t" \
"bne.n loop%=" : [t] "=r"(t) : [c] "I" (cycles)); \
}
}
#endif
uint64_t next_start_tick_ms = 0;
@ -88,7 +87,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t* digitalinout,
asm("nop; nop;");
#endif
#ifdef SAMD51
delay_cycles(18);
delay_cycles(3);
#endif
if(p & bitMask) {
// This is the high delay unique to a one bit.
@ -97,7 +96,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t* digitalinout,
asm("nop; nop; nop; nop; nop; nop; nop;");
#endif
#ifdef SAMD51
delay_cycles(25);
delay_cycles(11);
#endif
*clr = pinMask;
} else {
@ -108,7 +107,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t* digitalinout,
asm("nop; nop;");
#endif
#ifdef SAMD51
delay_cycles(25);
delay_cycles(3);
#endif
}
if((bitMask >>= 1) != 0) {
@ -119,7 +118,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t* digitalinout,
asm("nop; nop; nop; nop; nop;");
#endif
#ifdef SAMD51
delay_cycles(44);
delay_cycles(20);
#endif
} else {
if(ptr >= end) break;
@ -130,7 +129,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t* digitalinout,
// above operations take.
// For the SK6812 its 0.6us +- 0.15us
#ifdef SAMD51
delay_cycles(50);
delay_cycles(15);
#endif
}
}