[U-Boot] [PATCH 2/2 V3] ppc4xx: Initialize magnetic couplers in PLU405
Matthias Fuchs
matthias.fuchs at esd.eu
Mon Oct 26 09:58:45 CET 2009
This patch fixes an ugly behavior of the IL712 magnetic couplers
as used on PLU405. These parts will remember their last state
over a power cycle which might cause unwanted behavior.
Signed-off-by: Matthias Fuchs <matthias.fuchs at esd.eu>
---
V2:
- use C struct to access CAN controller registes
V3:
- move SJA1000 stuff into separate header
(see preceding patch)
- some renaming
board/esd/plu405/plu405.c | 36 ++++++++++++++++++++++++++++++++++++
include/configs/PLU405.h | 3 ++-
2 files changed, 38 insertions(+), 1 deletions(-)
diff --git a/board/esd/plu405/plu405.c b/board/esd/plu405/plu405.c
index 1841cda..fea7b26 100644
--- a/board/esd/plu405/plu405.c
+++ b/board/esd/plu405/plu405.c
@@ -26,6 +26,7 @@
#include <asm/io.h>
#include <command.h>
#include <malloc.h>
+#include <sja1000.h>
#undef FPGA_DEBUG
@@ -45,6 +46,34 @@ const unsigned char fpgadata[] =
*/
#include "../common/fpga.c"
+/*
+ * generate a short spike on the CAN tx line
+ * to bring the couplers in sync
+ */
+void init_coupler(u32 addr)
+{
+ struct sja1000_basic_s *ctrl = (struct sja1000_basic_s *)addr;
+
+ /* reset */
+ out_8(&ctrl->cr, CR_RR);
+
+ /* dominant */
+ out_8(&ctrl->btr0, 0x00); /* btr setup is required */
+ out_8(&ctrl->btr1, 0x14); /* we use 1Mbit/s */
+ out_8(&ctrl->oc, OC_TP1 | OC_TN1 | OC_POL1 |
+ OC_TP0 | OC_TN0 | OC_POL0 | OC_MODE1);
+ out_8(&ctrl->cr, 0x00);
+
+ /* delay */
+ in_8(&ctrl->cr);
+ in_8(&ctrl->cr);
+ in_8(&ctrl->cr);
+ in_8(&ctrl->cr);
+
+ /* reset */
+ out_8(&ctrl->cr, CR_RR);
+}
+
/* Prototypes */
int gunzip(void *, int, unsigned char *, unsigned long *);
@@ -198,6 +227,13 @@ int misc_init_r(void)
out_8((void *)DUART1_BA + 1, fctr); /* write FCTR */
out_8((void *)DUART1_BA + 3, 0); /* write LCR */
+ /*
+ * Init magnetic couplers
+ */
+ if (!getenv("noinitcoupler")) {
+ init_coupler(CAN0_BA);
+ init_coupler(CAN1_BA);
+ }
return 0;
}
diff --git a/include/configs/PLU405.h b/include/configs/PLU405.h
index 07fc715..b6740de 100644
--- a/include/configs/PLU405.h
+++ b/include/configs/PLU405.h
@@ -298,7 +298,8 @@
/*
* External Bus Controller (EBC) Setup
*/
-#define CAN_BA 0xF0000000 /* CAN Base Address */
+#define CAN0_BA 0xF0000000 /* CAN0 Base Address */
+#define CAN1_BA 0xF0000100 /* CAN1 Base Address */
#define DUART0_BA 0xF0000400 /* DUART Base Address */
#define DUART1_BA 0xF0000408 /* DUART Base Address */
#define RTC_BA 0xF0000500 /* RTC Base Address */
--
1.6.1
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