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>
This commit is contained in:
Holger Brunck 2017-05-17 17:24:38 +02:00 committed by David S. Miller
parent c7f235a7c2
commit 067bb938da
3 changed files with 38 additions and 0 deletions

View File

@ -98,6 +98,13 @@ static int uhdlc_init(struct ucc_hdlc_private *priv)
uf_info->tsa = 1; uf_info->tsa = 1;
uf_info->ctsp = 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 | uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
UCC_HDLC_UCCE_TXB) << 16); UCC_HDLC_UCCE_TXB) << 16);
@ -135,6 +142,28 @@ static int uhdlc_init(struct ucc_hdlc_private *priv)
/* Set UPSMR normal mode (need fixed)*/ /* Set UPSMR normal mode (need fixed)*/
iowrite32be(0, &priv->uf_regs->upsmr); 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->rx_ring_size = RX_BD_RING_LEN;
priv->tx_ring_size = TX_BD_RING_LEN; priv->tx_ring_size = TX_BD_RING_LEN;
/* Alloc Rx BD */ /* 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)) if (of_get_property(np, "fsl,ucc-internal-loopback", NULL))
uhdlc_priv->loopback = 1; uhdlc_priv->loopback = 1;
if (of_get_property(np, "fsl,hdlc-bus", NULL))
uhdlc_priv->hdlc_bus = 1;
if (uhdlc_priv->tsa == 1) { if (uhdlc_priv->tsa == 1) {
utdm = kzalloc(sizeof(*utdm), GFP_KERNEL); utdm = kzalloc(sizeof(*utdm), GFP_KERNEL);
if (!utdm) { if (!utdm) {

View File

@ -78,6 +78,7 @@ struct ucc_hdlc_private {
u16 tsa; u16 tsa;
bool hdlc_busy; bool hdlc_busy;
bool loopback; bool loopback;
bool hdlc_bus;
u8 *tx_buffer; u8 *tx_buffer;
u8 *rx_buffer; u8 *rx_buffer;

View File

@ -789,6 +789,11 @@ struct ucc_slow_pram {
#define UCC_GETH_UPSMR_SMM 0x00000080 #define UCC_GETH_UPSMR_SMM 0x00000080
#define UCC_GETH_UPSMR_SGMM 0x00000020 #define UCC_GETH_UPSMR_SGMM 0x00000020
/* UCC Protocol Specific Mode Register (UPSMR), when used for HDLC */
#define UCC_HDLC_UPSMR_RTE 0x02000000
#define UCC_HDLC_UPSMR_BUS 0x00200000
#define UCC_HDLC_UPSMR_CW8 0x00007000
/* UCC Transmit On Demand Register (UTODR) */ /* UCC Transmit On Demand Register (UTODR) */
#define UCC_SLOW_TOD 0x8000 #define UCC_SLOW_TOD 0x8000
#define UCC_FAST_TOD 0x8000 #define UCC_FAST_TOD 0x8000