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From: lra@sics.se
To: xen-devel@lists.xensource.com
Cc: Lars Rasmusson <Lars.Rasmusson@sics.se>
Subject: [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART
Date: Thu, 17 Jan 2013 15:08:59 +0100	[thread overview]
Message-ID: <1358431739-14349-1-git-send-email-lra@sics.se> (raw)
In-Reply-To: <1358428780.13856.57.camel@zakaz.uk.xensource.com>

From: Lars Rasmusson <Lars.Rasmusson@sics.se>

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>
---
 xen/arch/arm/arm32/head.S |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S
index 4782f11..20e9da6 100644
--- 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
-- 
1.7.9.5

  reply	other threads:[~2013-01-17 14:08 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-01-10 19:18 Xen-arm patch to early init_uart in head.S lra
2013-01-11 10:03 ` Ian Campbell
2013-01-17 13:19   ` Ian Campbell
2013-01-17 14:08     ` lra [this message]
2013-01-17 16:49       ` [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART Ian Campbell
  -- strict thread matches above, loose matches on Subject: below --
2013-01-10 20:02 lra

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