summaryrefslogtreecommitdiff
path: root/software
diff options
context:
space:
mode:
Diffstat (limited to 'software')
-rw-r--r--software/hello/hello.c2
-rw-r--r--software/led_fade/.unsupported-boards2
-rw-r--r--software/smp/Makefile6
-rw-r--r--software/smp/atomic.h29
-rw-r--r--software/smp/smp.c40
5 files changed, 77 insertions, 2 deletions
diff --git a/software/hello/hello.c b/software/hello/hello.c
index 85c5d87..befc6ee 100644
--- a/software/hello/hello.c
+++ b/software/hello/hello.c
@@ -2,7 +2,7 @@
int main()
{
- printf("hello world!\n");
+ puts("hello world!\n");
return 0;
}
diff --git a/software/led_fade/.unsupported-boards b/software/led_fade/.unsupported-boards
index ad80e34..f9e9897 100644
--- a/software/led_fade/.unsupported-boards
+++ b/software/led_fade/.unsupported-boards
@@ -1,4 +1,4 @@
freedom-e300-arty
coreplexip-e31-arty
coreplexip-e51-arty
-
+freedom-e300-arty
diff --git a/software/smp/Makefile b/software/smp/Makefile
new file mode 100644
index 0000000..4131ffc
--- /dev/null
+++ b/software/smp/Makefile
@@ -0,0 +1,6 @@
+TARGET = smp
+C_SRCS += smp.c
+CFLAGS += -O2 -fno-builtin-printf -DENABLE_SMP
+
+BSP_BASE = ../../bsp
+include $(BSP_BASE)/env/common.mk
diff --git a/software/smp/atomic.h b/software/smp/atomic.h
new file mode 100644
index 0000000..074c6a2
--- /dev/null
+++ b/software/smp/atomic.h
@@ -0,0 +1,29 @@
+#ifndef SIFIVE_ATOMIC_H
+#define SIFIVE_ATOMIC_H
+
+#define ATOMIC_INIT(x) \
+ { \
+ .counter = (x), \
+ }
+
+typedef struct {
+ int counter;
+} atomic_t;
+
+static inline int atomic_xchg(atomic_t *v, int n)
+{
+ register int c;
+
+ __asm__ __volatile__ (
+ "amoswap.w.aqrl %0, %2, %1"
+ : "=r" (c), "+A" (v->counter)
+ : "r" (n));
+ return c;
+}
+
+static inline void mb(void)
+{
+ __asm__ __volatile__ ("fence");
+}
+
+#endif
diff --git a/software/smp/smp.c b/software/smp/smp.c
new file mode 100644
index 0000000..36c9db9
--- /dev/null
+++ b/software/smp/smp.c
@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include <unistd.h>
+#include "atomic.h"
+void write_hex(int, unsigned long);
+
+atomic_t tty_lock = ATOMIC_INIT(0);
+
+void get_lock(atomic_t *lock)
+{
+ while (atomic_xchg(lock, 1) == 1);
+ mb();
+}
+
+void put_lock(atomic_t *lock)
+{
+ mb();
+ atomic_xchg(lock, 0);
+}
+
+int secondary_main(int hartid)
+{
+ volatile int counter;
+
+ while (1) {
+ get_lock(&tty_lock);
+ write(1, "hello world from hart ", 22);
+ char s[] = {'0', '\n', '\0'};
+ s[0] += hartid;
+ write(1, s, 2);
+ put_lock(&tty_lock);
+
+ for (counter = 0; counter < 10000 + 100*hartid; ++counter)
+ mb();
+ }
+}
+
+int main()
+{
+ return secondary_main(0);
+}