1 files changed, 59 insertions, 0 deletions
diff --git a/xen/arch/arm/arm64/debug-pl011.inc b/xen/arch/arm/arm64/debug-pl011.inc
new file mode 100644
index 0000000000..ee6e0e03e7
--- /dev/null
+++ b/xen/arch/arm/arm64/debug-pl011.inc
@@ -0,0 +1,59 @@
+/*
+ * xen/arch/arm/arm64/debug-pl011.S
+ *
+ * PL011 specific debug code
+ *
+ * Copyright (c) 2013 Citrix Systems.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/asm_defns.h>
+
+#define EARLY_UART_BASE_ADDRESS 0x1c090000
+
+/* PL011 UART initialization
+ * xb: register which containts the UART base address
+ * c: scratch register number */
+.macro early_uart_init xb, c
+        mov   x\c, #0x0
+        strh  w\c, [\xb, #0x28]      /* -> UARTFBRD (Baud divisor fraction) */
+        mov   x\c, #0x4              /* 7.3728MHz / 0x4 == 16 * 115200 */
+        strh  w\c, [\xb, #0x24]      /* -> UARTIBRD (Baud divisor integer) */
+        mov   x\c, #0x60             /* 8n1 */
+        str   w\c, [\xb, #0x2C]      /* -> UARTLCR_H (Line control) */
+        ldr   x\c, =0x00000301       /* RXE | TXE | UARTEN */
+        str   w\c, [\xb, #0x30]      /* -> UARTCR (Control Register) */
+.endm
+
+/* PL011 UART wait UART to be ready to transmit
+ * xb: register which contains the UART base address
+ * c: scratch register number */
+.macro early_uart_ready xb, c
+1:
+        ldrh  w\c, [\xb, #0x18]      /* <- UARTFR (Flag register) */
+        tst   w\c, #0x8              /* Check BUSY bit */
+        b.ne  1b                     /* Wait for the UART to be ready */
+.endm
+
+/* PL011 UART transmit character
+ * xb: register which contains the UART base address
+ * wt: register which contains the character to transmit */
+.macro early_uart_transmit xb, wt
+        strb  \wt, [\xb]             /* -> UARTDR (Data Register) */
+.endm
+
+/*
+ * Local variables:
+ * mode: ASM
+ * indent-tabs-mode: nil
+ * End:
+ */