From be0db3e3141c6c6b4e232b51091f35a284cc54e5 Mon Sep 17 00:00:00 2001 From: Matthias Fuchs Date: Mon, 26 Oct 2009 09:58:45 +0100 Subject: ppc4xx: Initialize magnetic couplers in PLU405 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 Signed-off-by: Stefan Roese --- board/esd/plu405/plu405.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'board') diff --git a/board/esd/plu405/plu405.c b/board/esd/plu405/plu405.c index f14ef7a..c733587 100644 --- a/board/esd/plu405/plu405.c +++ b/board/esd/plu405/plu405.c @@ -26,6 +26,7 @@ #include #include #include +#include #undef FPGA_DEBUG @@ -61,6 +62,34 @@ au_image_t au_image[] = { int N_AU_IMAGES = (sizeof(au_image) / sizeof(au_image[0])); +/* + * 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 *); @@ -214,6 +243,13 @@ 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; } -- cgit v1.1