From fbcb7ece0ea1e364180f1cf963e0fa0ce7f6560d Mon Sep 17 00:00:00 2001 From: Remy Bohmer Date: Tue, 3 Jun 2008 15:26:24 +0200 Subject: [PATCH] DM9000: Improve eth_reset() routine According to the application notes of the DM9000 v1.22 chapter 5.2 bullet 2, the reset procedure must be done twice to properly reset the DM9000 by means of software. This errata is not needed anymore for the DM9000A, but it does not bother it. This change has been tested with DM9000A, DM9000E, DM9000EP. Signed-off-by: Remy Bohmer Signed-off-by: Ben Warren --- drivers/net/dm9000x.c | 34 +++++++++++++++++++++++++++++++--- 1 file changed, 31 insertions(+), 3 deletions(-) diff --git a/drivers/net/dm9000x.c b/drivers/net/dm9000x.c index c6c24dd6fb..5b00e9588f 100644 --- a/drivers/net/dm9000x.c +++ b/drivers/net/dm9000x.c @@ -45,6 +45,8 @@ v1.2 03/18/2003 Weilun Huang : - Adapt eth_send such that it matches the DM9000* application notes. Needed to make it work properly for DM9000A. + - Adapted reset procedure to match DM9000 application + notes (i.e. double reset) These changes are tested with DM9000{A,EP,E} together with a 200MHz Atmel AT91SAM92161 core @@ -362,9 +364,35 @@ identify_nic(void) static void dm9000_reset(void) { - DM9000_DBG("resetting\n"); - DM9000_iow(DM9000_NCR, NCR_RST); - udelay(1000); /* delay 1ms */ + DM9000_DBG("resetting DM9000\n"); + + /* Reset DM9000, + see DM9000 Application Notes V1.22 Jun 11, 2004 page 29 */ + + /* DEBUG: Make all GPIO pins outputs */ + DM9000_iow(DM9000_GPCR, 0x0F); + /* Step 1: Power internal PHY by writing 0 to GPIO0 pin */ + DM9000_iow(DM9000_GPR, 0); + /* Step 2: Software reset */ + DM9000_iow(DM9000_NCR, 3); + + do { + DM9000_DBG("resetting the DM9000, 1st reset\n"); + udelay(25); /* Wait at least 20 us */ + } while (DM9000_ior(DM9000_NCR) & 1); + + DM9000_iow(DM9000_NCR, 0); + DM9000_iow(DM9000_NCR, 3); /* Issue a second reset */ + + do { + DM9000_DBG("resetting the DM9000, 2nd reset\n"); + udelay(25); /* Wait at least 20 us */ + } while (DM9000_ior(DM9000_NCR) & 1); + + /* Check whether the ethernet controller is present */ + if ((DM9000_ior(DM9000_PIDL) != 0x0) || + (DM9000_ior(DM9000_PIDH) != 0x90)) + printf("ERROR: resetting DM9000 -> not responding\n"); } /* Initilize dm9000 board -- GitLab