From: Keith Packard <keithp@keithp.com>
Date: Sun, 27 May 2012 03:01:46 +0000 (-0600)
Subject: avr: Block interrupts while executing SPI slave code
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=19b23594a04fc72fd7d2e106c5877b670662001d

avr: Block interrupts while executing SPI slave code

Any interrupts do very bad things to our SPI reliability. Block
interrupts for the whole of the SPI slave ISR.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/src-avr/ao_spi_slave.c b/src-avr/ao_spi_slave.c
index 9ef30ead..a524f31f 100644
--- a/src-avr/ao_spi_slave.c
+++ b/src-avr/ao_spi_slave.c
@@ -84,15 +84,13 @@ static uint8_t ao_spi_slave_recv(void)
 
 static uint8_t ao_spi_slave_running;
 
-ISR(PCINT0_vect)
+ISR(PCINT0_vect, ISR_BLOCK)
 {
 	if ((PINB & (1 << PINB0)) == 0) {
 		if (!ao_spi_slave_running) {
 			uint8_t	changed;
 			ao_spi_slave_running = 1;
-			cli();
 			changed = ao_spi_slave_recv();
-			sei();
 			if (changed && ao_flight_boost <= ao_log_store.tm_state) {
 				if (ao_log_store.tm_state < ao_flight_landed)
 					ao_log_start();