libplatsupport: fix CR/LF handling

Fix the bug that LF CR is printed instead of CR LF. Signed-off-by: Axel Heider <axel.heider@hensoldt.net>
seL4 · May 8, 2023 · 5e8b634 · 5e8b634
1 parent 3b1177d
commit 5e8b634
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/libplatsupport/src/plat/fvp/serial.c b/libplatsupport/src/plat/fvp/serial.c
@@ -34,13 +34,15 @@ int uart_getchar(ps_chardevice_t *d)
 
 int uart_putchar(ps_chardevice_t *d, int c)
 {
-    while ((*REG_PTR(d->vaddr, UARTFR) & PL011_UARTFR_TXFF) != 0);
-
-    *REG_PTR(d->vaddr, UARTDR) = c;
     if (c == '\n' && (d->flags & SERIAL_AUTO_CR)) {
         uart_putchar(d, '\r');
     }
 
+    while ((*REG_PTR(d->vaddr, UARTFR) & PL011_UARTFR_TXFF) != 0) {
+        /* busy loop */
+    }
+    *REG_PTR(d->vaddr, UARTDR) = c;
+
     return c;
 }
 

diff --git a/libplatsupport/src/plat/hikey/serial.c b/libplatsupport/src/plat/hikey/serial.c
@@ -31,13 +31,15 @@ int uart_getchar(ps_chardevice_t *d)
 
 int uart_putchar(ps_chardevice_t *d, int c)
 {
-    while ((*REG_PTR(d->vaddr, UARTFR) & PL011_UARTFR_TXFF) != 0);
-
-    *REG_PTR(d->vaddr, UARTDR) = c;
     if (c == '\n' && (d->flags & SERIAL_AUTO_CR)) {
         uart_putchar(d, '\r');
     }
 
+    while ((*REG_PTR(d->vaddr, UARTFR) & PL011_UARTFR_TXFF) != 0) {
+        /* busy loop */
+    }
+    *REG_PTR(d->vaddr, UARTDR) = c;
+
     return c;
 }