diff options
| author | Holger Brunck <holger.brunck@keymile.com> | 2017-05-17 17:24:38 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-05-18 10:28:39 -0400 |
| commit | 067bb938dad61e58fc3d6a0e090b72ec011851cd (patch) | |
| tree | 617e9b79f94dfe0cdff171fae024b7f13353b657 /drivers/net/wan/fsl_ucc_hdlc.c | |
| parent | c7f235a7c2d09b1b83671ba2d93ebee981554467 (diff) | |
| download | linux-067bb938dad61e58fc3d6a0e090b72ec011851cd.tar.bz2 | |
net/wan/fsl_ucc_hdlc: add hdlc-bus support
This adds support for hdlc-bus mode to the fsl_ucc_hdlc driver. This can
be enabled with the "fsl,hdlc-bus" property in the DTS node of the
corresponding ucc.
This aligns the configuration of the UPSMR and GUMR registers to what is
done in our ucc_hdlc driver (that only support hdlc-bus mode) and with
the QuickEngine's documentation for hdlc-bus mode.
GUMR/SYNL is set to AUTO for the busmode as in this case the CD signal
is ignored. The brkpt_support is enabled to set the HBM1 bit in the
CMXUCR register to configure an open-drain connected HDLC bus.
Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Cc: Zhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/wan/fsl_ucc_hdlc.c')
| -rw-r--r-- | drivers/net/wan/fsl_ucc_hdlc.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c index 4c93d561b18a..e9b2d687f150 100644 --- a/drivers/net/wan/fsl_ucc_hdlc.c +++ b/drivers/net/wan/fsl_ucc_hdlc.c @@ -98,6 +98,13 @@ static int uhdlc_init(struct ucc_hdlc_private *priv) uf_info->tsa = 1; uf_info->ctsp = 1; } + + /* This sets HPM register in CMXUCR register which configures a + * open drain connected HDLC bus + */ + if (priv->hdlc_bus) + uf_info->brkpt_support = 1; + uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF | UCC_HDLC_UCCE_TXB) << 16); @@ -135,6 +142,28 @@ static int uhdlc_init(struct ucc_hdlc_private *priv) /* Set UPSMR normal mode (need fixed)*/ iowrite32be(0, &priv->uf_regs->upsmr); + /* hdlc_bus mode */ + if (priv->hdlc_bus) { + u32 upsmr; + + dev_info(priv->dev, "HDLC bus Mode\n"); + upsmr = ioread32be(&priv->uf_regs->upsmr); + + /* bus mode and retransmit enable, with collision window + * set to 8 bytes + */ + upsmr |= UCC_HDLC_UPSMR_RTE | UCC_HDLC_UPSMR_BUS | + UCC_HDLC_UPSMR_CW8; + iowrite32be(upsmr, &priv->uf_regs->upsmr); + + /* explicitly disable CDS & CTSP */ + gumr = ioread32be(&priv->uf_regs->gumr); + gumr &= ~(UCC_FAST_GUMR_CDS | UCC_FAST_GUMR_CTSP); + /* set automatic sync to explicitly ignore CD signal */ + gumr |= UCC_FAST_GUMR_SYNL_AUTO; + iowrite32be(gumr, &priv->uf_regs->gumr); + } + priv->rx_ring_size = RX_BD_RING_LEN; priv->tx_ring_size = TX_BD_RING_LEN; /* Alloc Rx BD */ @@ -1046,6 +1075,9 @@ static int ucc_hdlc_probe(struct platform_device *pdev) if (of_get_property(np, "fsl,ucc-internal-loopback", NULL)) uhdlc_priv->loopback = 1; + if (of_get_property(np, "fsl,hdlc-bus", NULL)) + uhdlc_priv->hdlc_bus = 1; + if (uhdlc_priv->tsa == 1) { utdm = kzalloc(sizeof(*utdm), GFP_KERNEL); if (!utdm) { |