xen: arm: Correct register values and comment in early init_uart.

Set register values and comment in early init_uart to match
documentation of PL011 UART

Reading the PL011 UART documentation on
http://infocenter.arm.com/help/topic/com.arm.doc.ddi0183f/DDI0183.pdf
in sec 3.2 shows the early initialisation of the UART on the Versatile Express
is incorrect.  This fixes it.

Signed-off-by: Lars Rasmusson <Lars.Rasmusson@sics.se>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S
index 4782f1131df1871bbd9bb0fdfb0ecab52315780c..20e9da6228ad69b1597257b4488bd82b7c22d21c 100644 (file)
--- a/xen/arch/arm/arm32/head.S
+++ b/xen/arch/arm/arm32/head.S
@@ -352,11 +352,11 @@ fail:   PRINT("- Boot failed -\r\n")
  * Clobbers r0-r2 */
 init_uart:
         mov   r1, #0x0
-        str   r1, [r11, #0x24]       /* -> UARTIBRD (Baud divisor fraction) */
+        str   r1, [r11, #0x28]       /* -> UARTFBRD (Baud divisor fraction) */
         mov   r1, #0x4               /* 7.3728MHz / 0x4 == 16 * 115200 */
         str   r1, [r11, #0x24]       /* -> UARTIBRD (Baud divisor integer) */
         mov   r1, #0x60              /* 8n1 */
-        str   r1, [r11, #0x24]       /* -> UARTLCR_H (Line control) */
+        str   r1, [r11, #0x2C]       /* -> UARTLCR_H (Line control) */
         ldr   r1, =0x00000301        /* RXE | TXE | UARTEN */
         str   r1, [r11, #0x30]       /* -> UARTCR (Control Register) */
         adr   r0, 1f