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author | Matthias Fuchs <matthias.fuchs@esd-electronics.com> | 2009-10-27 19:58:09 +0100 |
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committer | Stefan Roese <sr@denx.de> | 2009-11-17 13:36:35 +0100 |
commit | 3ffc0d61bad7d986e344ce7062b37c5c8f04fb0e (patch) | |
tree | 55924ea6c4f90e85b5a8367b6d4ca3826d4a6e25 /board/esd/vom405/vom405.c | |
parent | be0db3e3141c6c6b4e232b51091f35a284cc54e5 (diff) | |
download | u-boot-imx-3ffc0d61bad7d986e344ce7062b37c5c8f04fb0e.zip u-boot-imx-3ffc0d61bad7d986e344ce7062b37c5c8f04fb0e.tar.gz u-boot-imx-3ffc0d61bad7d986e344ce7062b37c5c8f04fb0e.tar.bz2 |
ppc4xx: Initialize magnetic coupler on VOM405 boards
This patch fixes an ugly behavior of the IL712 magnetic coupler
as used on VOM405. These parts will remember their last state
over a power cycle which might cause unwanted behavior.
Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
Signed-off-by: Stefan Roese <sr@denx.de>
Diffstat (limited to 'board/esd/vom405/vom405.c')
-rw-r--r-- | board/esd/vom405/vom405.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/board/esd/vom405/vom405.c b/board/esd/vom405/vom405.c index fb48022..de35036 100644 --- a/board/esd/vom405/vom405.c +++ b/board/esd/vom405/vom405.c @@ -26,11 +26,40 @@ #include <asm/io.h> #include <command.h> #include <malloc.h> +#include <sja1000.h> DECLARE_GLOBAL_DATA_PTR; extern void lxt971_no_sleep(void); +/* + * 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); +} + int board_early_init_f (void) { /* @@ -77,6 +106,12 @@ int misc_init_r (void) gd->bd->bi_flashstart = 0 - gd->bd->bi_flashsize; gd->bd->bi_flashoffset = 0; + /* + * Init magnetic coupler + */ + if (!getenv("noinitcoupler")) + init_coupler(CAN_BA); + return (0); } |