#define set_desc_next(a,b) (a).next = cpu_to_le32((unsigned int)(b))
#define set_desc_count(a,b)(a).count = cpu_to_le16((unsigned short)(b))
#define set_desc_eof(a,b) (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
+#define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
#define desc_count(a) (le16_to_cpu((a).count))
#define desc_status(a) (le16_to_cpu((a).status))
#define desc_complete(a) (le16_to_cpu((a).status) & BIT15)
u32 max_frame_size; /* as set by device config */
unsigned int rbuf_fill_level;
+ unsigned int rx_pio;
unsigned int if_mode;
unsigned int base_clock;
struct slgt_desc *rbufs;
unsigned int rbuf_current;
unsigned int rbuf_index;
+ unsigned int rbuf_fill_index;
+ unsigned short rbuf_fill_count;
unsigned int tbuf_count;
struct slgt_desc *tbufs;
static unsigned int tbuf_bytes(struct slgt_info *info);
static void reset_tbufs(struct slgt_info *info);
static void tdma_reset(struct slgt_info *info);
-static void tdma_start(struct slgt_info *info);
static void tx_load(struct slgt_info *info, const char *buf, unsigned int count);
static void get_signals(struct slgt_info *info);
}
}
+static void update_tx_timer(struct slgt_info *info)
+{
+ /*
+ * use worst case speed of 1200bps to calculate transmit timeout
+ * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
+ */
+ if (info->params.mode == MGSL_MODE_HDLC) {
+ int timeout = (tbuf_bytes(info) * 7) + 1000;
+ mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
+ }
+}
+
static int write(struct tty_struct *tty,
const unsigned char *buf, int count)
{
spin_lock_irqsave(&info->lock,flags);
if (!info->tx_active)
tx_start(info);
- else
- tdma_start(info);
+ else if (!(rd_reg32(info, TDCSR) & BIT0)) {
+ /* transmit still active but transmit DMA stopped */
+ unsigned int i = info->tbuf_current;
+ if (!i)
+ i = info->tbuf_count;
+ i--;
+ /* if DMA buf unsent must try later after tx idle */
+ if (desc_count(info->tbufs[i]))
+ ret = 0;
+ }
+ if (ret > 0)
+ update_tx_timer(info);
spin_unlock_irqrestore(&info->lock,flags);
}
/* save start time for transmit timeout detection */
dev->trans_start = jiffies;
- /* start hardware transmitter if necessary */
spin_lock_irqsave(&info->lock,flags);
- if (!info->tx_active)
- tx_start(info);
+ tx_start(info);
+ update_tx_timer(info);
spin_unlock_irqrestore(&info->lock,flags);
return 0;
info->pending_bh |= BH_STATUS;
}
+static void isr_rxdata(struct slgt_info *info)
+{
+ unsigned int count = info->rbuf_fill_count;
+ unsigned int i = info->rbuf_fill_index;
+ unsigned short reg;
+
+ while (rd_reg16(info, SSR) & IRQ_RXDATA) {
+ reg = rd_reg16(info, RDR);
+ DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
+ if (desc_complete(info->rbufs[i])) {
+ /* all buffers full */
+ rx_stop(info);
+ info->rx_restart = 1;
+ continue;
+ }
+ info->rbufs[i].buf[count++] = (unsigned char)reg;
+ /* async mode saves status byte to buffer for each data byte */
+ if (info->params.mode == MGSL_MODE_ASYNC)
+ info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
+ if (count == info->rbuf_fill_level || (reg & BIT10)) {
+ /* buffer full or end of frame */
+ set_desc_count(info->rbufs[i], count);
+ set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
+ info->rbuf_fill_count = count = 0;
+ if (++i == info->rbuf_count)
+ i = 0;
+ info->pending_bh |= BH_RECEIVE;
+ }
+ }
+
+ info->rbuf_fill_index = i;
+ info->rbuf_fill_count = count;
+}
+
static void isr_serial(struct slgt_info *info)
{
unsigned short status = rd_reg16(info, SSR);
if (info->tx_count)
isr_txeom(info, status);
}
+ if (info->rx_pio && (status & IRQ_RXDATA))
+ isr_rxdata(info);
if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
info->icount.brk++;
/* process break detection if tty control allows */
} else {
if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
isr_txeom(info, status);
-
+ if (info->rx_pio && (status & IRQ_RXDATA))
+ isr_rxdata(info);
if (status & IRQ_RXIDLE) {
if (status & RXIDLE)
info->icount.rxidle++;
return -EINVAL;
}
info->rbuf_fill_level = rbuf_fill_level;
+ if (rbuf_fill_level < 128)
+ info->rx_pio = 1; /* PIO mode */
+ else
+ info->rx_pio = 0; /* DMA mode */
rx_stop(info); /* restart receiver to use new fill level */
}
return (info->signals & SerialSignal_DCD) ? 1 : 0;
}
-static void raise_dtr_rts(struct tty_port *port)
+static void dtr_rts(struct tty_port *port, int on)
{
unsigned long flags;
struct slgt_info *info = container_of(port, struct slgt_info, port);
spin_lock_irqsave(&info->lock,flags);
- info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+ if (on)
+ info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+ else
+ info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
}
static const struct tty_port_operations slgt_port_ops = {
.carrier_raised = carrier_raised,
- .raise_dtr_rts = raise_dtr_rts,
+ .dtr_rts = dtr_rts,
};
/*
rdma_reset(info);
reset_rbufs(info);
- /* set 1st descriptor address */
- wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
-
- if (info->params.mode != MGSL_MODE_ASYNC) {
- /* enable rx DMA and DMA interrupt */
- wr_reg32(info, RDCSR, (BIT2 + BIT0));
+ if (info->rx_pio) {
+ /* rx request when rx FIFO not empty */
+ wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
+ slgt_irq_on(info, IRQ_RXDATA);
+ if (info->params.mode == MGSL_MODE_ASYNC) {
+ /* enable saving of rx status */
+ wr_reg32(info, RDCSR, BIT6);
+ }
} else {
- /* enable saving of rx status, rx DMA and DMA interrupt */
- wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
+ /* rx request when rx FIFO half full */
+ wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
+ /* set 1st descriptor address */
+ wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
+
+ if (info->params.mode != MGSL_MODE_ASYNC) {
+ /* enable rx DMA and DMA interrupt */
+ wr_reg32(info, RDCSR, (BIT2 + BIT0));
+ } else {
+ /* enable saving of rx status, rx DMA and DMA interrupt */
+ wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
+ }
}
slgt_irq_on(info, IRQ_RXOVER);
slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
/* clear tx idle and underrun status bits */
wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
- if (info->params.mode == MGSL_MODE_HDLC)
- mod_timer(&info->tx_timer, jiffies +
- msecs_to_jiffies(5000));
} else {
slgt_irq_off(info, IRQ_TXDATA);
slgt_irq_on(info, IRQ_TXIDLE);
/* clear tx idle status bit */
wr_reg16(info, SSR, IRQ_TXIDLE);
}
- tdma_start(info);
+ /* set 1st descriptor address and start DMA */
+ wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
+ wr_reg32(info, TDCSR, BIT2 + BIT0);
info->tx_active = true;
}
}
-/*
- * start transmit DMA if inactive and there are unsent buffers
- */
-static void tdma_start(struct slgt_info *info)
-{
- unsigned int i;
-
- if (rd_reg32(info, TDCSR) & BIT0)
- return;
-
- /* transmit DMA inactive, check for unsent buffers */
- i = info->tbuf_start;
- while (!desc_count(info->tbufs[i])) {
- if (++i == info->tbuf_count)
- i = 0;
- if (i == info->tbuf_current)
- return;
- }
- info->tbuf_start = i;
-
- /* there are unsent buffers, start transmit DMA */
-
- /* reset needed if previous error condition */
- tdma_reset(info);
-
- /* set 1st descriptor address */
- wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
- wr_reg32(info, TDCSR, BIT2 + BIT0); /* IRQ + DMA enable */
-}
-
static void tx_stop(struct slgt_info *info)
{
unsigned short val;
static void reset_rbufs(struct slgt_info *info)
{
free_rbufs(info, 0, info->rbuf_count - 1);
+ info->rbuf_fill_index = 0;
+ info->rbuf_fill_count = 0;
}
/*
info->icount.txtimeout++;
}
spin_lock_irqsave(&info->lock,flags);
- info->tx_active = false;
- info->tx_count = 0;
+ tx_stop(info);
spin_unlock_irqrestore(&info->lock,flags);
#if SYNCLINK_GENERIC_HDLC