added mem-block semaphore

2022-08-30 19:01:21 +02:00
parent 4c67d0bba4
commit 6974c2b8e6
6 changed files with 68 additions and 18 deletions
@@ -0,0 +1,31 @@
+.thumb
+.syntax unified
+
+.text
+
+.globl  sem_post32
+.type   sem_post32, %function
+
+sem_post32:
+1:
+        ldrex           r2, [r0]
+        add             r2, r2, r1
+        strex           r3, r2, [r0]
+        teq             r3, #0
+        bne             1b
+        mov             r0, r2
+        bx              lr
+
+
+.globl  sem_wait32
+.type   sem_wait32, %function
+
+sem_wait32:
+1:
+        ldrex           r2, [r0]
+        sub             r2, r2, r1
+        strex           r3, r2, [r0]
+        teq             r3, #0
+        bne             1b
+        mov             r0, r2
+        bx              lr