* [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART
@ 2013-01-10 20:02 lra
0 siblings, 0 replies; 3+ messages in thread
From: lra @ 2013-01-10 20:02 UTC (permalink / raw)
To: xen-devel; +Cc: Lars Rasmusson
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. (Currently it probably works only because the default
values are sane.)
Signed-off-by: Lars Rasmusson <Lars.Rasmusson@sics.se>
---
xen/arch/arm/head.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/xen/arch/arm/head.S b/xen/arch/arm/head.S
index cdbe011..a884592 100644
--- a/xen/arch/arm/head.S
+++ b/xen/arch/arm/head.S
@@ -291,11 +291,11 @@ 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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART
2013-01-17 13:19 Xen-arm patch to early init_uart in head.S Ian Campbell
@ 2013-01-17 14:08 ` lra
2013-01-17 16:49 ` Ian Campbell
0 siblings, 1 reply; 3+ messages in thread
From: lra @ 2013-01-17 14:08 UTC (permalink / raw)
To: xen-devel; +Cc: Lars Rasmusson
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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART
2013-01-17 14:08 ` [PATCH] Set register values and comment in early init_uart to match documentation of PL011 UART lra
@ 2013-01-17 16:49 ` Ian Campbell
0 siblings, 0 replies; 3+ messages in thread
From: Ian Campbell @ 2013-01-17 16:49 UTC (permalink / raw)
To: lra@sics.se; +Cc: Lars Rasmusson, xen-devel@lists.xensource.com
On Thu, 2013-01-17 at 14:08 +0000, lra@sics.se wrote:
> 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>
Acked + applied. Thanks.
^ permalink raw reply [flat|nested] 3+ messages in thread
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2013-01-17 13:19 Xen-arm patch to early init_uart in head.S Ian Campbell
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