read/write doeas not block when uart is disabled

3 files changed, 11 insertions, 7 deletions

diff --git a/fw/fe310/bsp/gloss/sys_read.c b/fw/fe310/bsp/gloss/sys_read.c
index 1857fc6..cc14f2a 100644
--- a/fw/fe310/bsp/gloss/sys_read.c
+++ b/fw/fe310/bsp/gloss/sys_read.c
@@ -4,11 +4,13 @@
 
 #include "platform.h"
 
+#include "soc/uart.h"
+
 /* Read from a file.  */
 ssize_t
 _read(int fd, void *ptr, size_t len)
 {
-  if (fd != STDIN_FILENO) {
+  if ((fd != STDIN_FILENO) || !eos_uart_enabled()) {
     errno = ENOSYS;
     return -1;
   }
diff --git a/fw/fe310/bsp/gloss/sys_sbrk.c b/fw/fe310/bsp/gloss/sys_sbrk.c
index ce10c90..e789ec1 100644
--- a/fw/fe310/bsp/gloss/sys_sbrk.c
+++ b/fw/fe310/bsp/gloss/sys_sbrk.c
@@ -6,9 +6,9 @@
  * about it.  Note that there is no error checking anywhere in this file, users
  * will simply get the relevant error when actually trying to use the memory
  * that's been allocated. */
-extern char metal_segment_heap_target_start;
-extern char metal_segment_heap_target_end;
-static char *brk = &metal_segment_heap_target_start;
+extern char __heap_start;
+extern char __heap_end;
+static char *brk = &__heap_start;
 
 int
 _brk(void *addr)
@@ -23,12 +23,12 @@ _sbrk(ptrdiff_t incr)
   char *old = brk;
 
   /* If __heap_size == 0, we can't allocate memory on the heap */
-  if(&metal_segment_heap_target_start == &metal_segment_heap_target_end) {
+  if(&__heap_start == &__heap_end) {
     return (void *)-1;
   }
 
   /* Don't move the break past the end of the heap */
-  if ((brk + incr) <= &metal_segment_heap_target_end) {
+  if ((brk + incr) <= &__heap_end) {
     brk += incr;
   } else {
     return (void *)-1;
diff --git a/fw/fe310/bsp/gloss/sys_write.c b/fw/fe310/bsp/gloss/sys_write.c
index 458f9a4..e2bb832 100644
--- a/fw/fe310/bsp/gloss/sys_write.c
+++ b/fw/fe310/bsp/gloss/sys_write.c
@@ -4,13 +4,15 @@
 
 #include "platform.h"
 
+#include "soc/uart.h"
+
 #define PUTC(c)     { while (UART0_REG(UART_REG_TXFIFO) & 0x80000000); UART0_REG(UART_REG_TXFIFO) = (c); }
 
 /* Write to a file.  */
 ssize_t
 _write(int fd, const void *ptr, size_t len)
 {
-  if ((fd != STDOUT_FILENO) && (fd != STDERR_FILENO)) {
+  if ((fd != STDOUT_FILENO) && (fd != STDERR_FILENO) || !eos_uart_enabled()) {
     errno = ENOSYS;
     return -1;
   }