summaryrefslogtreecommitdiffstats
path: root/arch/blackfin
diff options
context:
space:
mode:
authorMike Frysinger <michael.frysinger@analog.com>2007-05-21 18:09:27 +0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-21 09:50:22 -0700
commit5079df993c3ab45af10dc9a45b3b9e712fd56f23 (patch)
tree9c978e20be84f4cc058d6a56cda5cdf497bc2be7 /arch/blackfin
parentef9256d2831df0896566c3823cd2bdf0e55df984 (diff)
downloadlinux-5079df993c3ab45af10dc9a45b3b9e712fd56f23.tar.bz2
Blackfin arch: document why we have to touch the UART peripheral in our boot up code
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com> Signed-off-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/blackfin')
-rw-r--r--arch/blackfin/mach-bf533/head.S3
-rw-r--r--arch/blackfin/mach-bf537/head.S3
-rw-r--r--arch/blackfin/mach-bf561/head.S3
3 files changed, 6 insertions, 3 deletions
diff --git a/arch/blackfin/mach-bf533/head.S b/arch/blackfin/mach-bf533/head.S
index 1a54ff5f061d..4db9e6240906 100644
--- a/arch/blackfin/mach-bf533/head.S
+++ b/arch/blackfin/mach-bf533/head.S
@@ -173,7 +173,8 @@ ENTRY(__stext)
STI R2;
#endif
- /* Initialise UART */
+ /* Initialise UART - when booting from u-boot, the UART is not disabled
+ * so if we dont initalize here, our serial console gets hosed */
p0.h = hi(UART_LCR);
p0.l = lo(UART_LCR);
r0 = 0x0(Z);
diff --git a/arch/blackfin/mach-bf537/head.S b/arch/blackfin/mach-bf537/head.S
index aafc686749ed..b4377dddc127 100644
--- a/arch/blackfin/mach-bf537/head.S
+++ b/arch/blackfin/mach-bf537/head.S
@@ -181,7 +181,8 @@ ENTRY(__stext)
SSYNC;
#endif
- /*Initialise UART*/
+ /* Initialise UART - when booting from u-boot, the UART is not disabled
+ * so if we dont initalize here, our serial console gets hosed */
p0.h = hi(UART_LCR);
p0.l = lo(UART_LCR);
r0 = 0x0(Z);
diff --git a/arch/blackfin/mach-bf561/head.S b/arch/blackfin/mach-bf561/head.S
index 04f3ac33ab0e..9c8e6885f4e7 100644
--- a/arch/blackfin/mach-bf561/head.S
+++ b/arch/blackfin/mach-bf561/head.S
@@ -127,7 +127,8 @@ ENTRY(__stext)
STI R2;
#endif
- /* Initialise UART*/
+ /* Initialise UART - when booting from u-boot, the UART is not disabled
+ * so if we dont initalize here, our serial console gets hosed */
p0.h = hi(UART_LCR);
p0.l = lo(UART_LCR);
r0 = 0x0(Z);