SERCOMM: make sure to disable IRQ/FIQ to avoid race conditions

1 files changed, 11 insertions, 0 deletions

diff --git a/src/target/firmware/comm/sercomm_cons.c b/src/target/firmware/comm/sercomm_cons.c
index 5b481bcb..6d31a9f7 100644
--- a/src/target/firmware/comm/sercomm_cons.c
+++ b/src/target/firmware/comm/sercomm_cons.c
@@ -24,6 +24,8 @@
 #include <errno.h>
 #include <string.h>
 
+#include <asm/system.h>
+
 #include <calypso/uart.h>
 
 #include <console.h>
@@ -50,6 +52,7 @@ static void raw_puts(const char *s)
 
 int sercomm_puts(const char *s)
 {
+	unsigned long flags;
 	const int len = strlen(s) + 1;
 	unsigned int bytes_left = len;
 
@@ -59,6 +62,12 @@ int sercomm_puts(const char *s)
 		return len - 1;
 	}
 
+	/* This function is called from any context: Supervisor, IRQ, FIQ, ...
+	 * as such, we need to ensure re-entrant calls are either supported or
+	 * avoided. */
+	local_irq_save(flags);
+	local_fiq_disable();
+
 	while (bytes_left > 0) {
 		unsigned int write_num, space_left, flush;
 		uint8_t *data;
@@ -110,6 +119,8 @@ int sercomm_puts(const char *s)
 		}
 	}
 
+	local_irq_restore(flags);
+
 	return len - 1;
 }