// SPDX-License-Identifier: GPL-2.0+ /************************************************************************ * Copyright 2003 Digi International (www.digi.com) * * Copyright (C) 2004 IBM Corporation. All rights reserved. * * Contact Information: * Scott H Kilau * Wendy Xiong * ***********************************************************************/ #include /* For udelay */ #include /* For the various UART offsets */ #include #include #include #include "jsm.h" /* Driver main header file */ static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 }; /* * This function allows calls to ensure that all outstanding * PCI writes have been completed, by doing a PCI read against * a non-destructive, read-only location on the Neo card. * * In this case, we are reading the DVID (Read-only Device Identification) * value of the Neo card. */ static inline void neo_pci_posting_flush(struct jsm_board *bd) { readb(bd->re_map_membase + 0x8D); } static void neo_set_cts_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n"); /* Turn on auto CTS flow control */ ier |= (UART_17158_IER_CTSDSR); efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR); /* Turn off auto Xon flow control */ efr &= ~(UART_17158_EFR_IXON); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); /* Turn on table D, with 8 char hi/low watermarks */ writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr); /* Feed the UART our trigger levels */ writeb(8, &ch->ch_neo_uart->tfifo); ch->ch_t_tlevel = 8; writeb(ier, &ch->ch_neo_uart->ier); } static void neo_set_rts_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n"); /* Turn on auto RTS flow control */ ier |= (UART_17158_IER_RTSDTR); efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR); /* Turn off auto Xoff flow control */ ier &= ~(UART_17158_IER_XOFF); efr &= ~(UART_17158_EFR_IXOFF); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr); ch->ch_r_watermark = 4; writeb(56, &ch->ch_neo_uart->rfifo); ch->ch_r_tlevel = 56; writeb(ier, &ch->ch_neo_uart->ier); /* * From the Neo UART spec sheet: * The auto RTS/DTR function must be started by asserting * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after * it is enabled. */ ch->ch_mostat |= (UART_MCR_RTS); } static void neo_set_ixon_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n"); /* Turn off auto CTS flow control */ ier &= ~(UART_17158_IER_CTSDSR); efr &= ~(UART_17158_EFR_CTSDSR); /* Turn on auto Xon flow control */ efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr); ch->ch_r_watermark = 4; writeb(32, &ch->ch_neo_uart->rfifo); ch->ch_r_tlevel = 32; /* Tell UART what start/stop chars it should be looking for */ writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1); writeb(0, &ch->ch_neo_uart->xonchar2); writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1); writeb(0, &ch->ch_neo_uart->xoffchar2); writeb(ier, &ch->ch_neo_uart->ier); } static void neo_set_ixoff_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n"); /* Turn off auto RTS flow control */ ier &= ~(UART_17158_IER_RTSDTR); efr &= ~(UART_17158_EFR_RTSDTR); /* Turn on auto Xoff flow control */ ier |= (UART_17158_IER_XOFF); efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); /* Turn on table D, with 8 char hi/low watermarks */ writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr); writeb(8, &ch->ch_neo_uart->tfifo); ch->ch_t_tlevel = 8; /* Tell UART what start/stop chars it should be looking for */ writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1); writeb(0, &ch->ch_neo_uart->xonchar2); writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1); writeb(0, &ch->ch_neo_uart->xoffchar2); writeb(ier, &ch->ch_neo_uart->ier); } static void neo_set_no_input_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n"); /* Turn off auto RTS flow control */ ier &= ~(UART_17158_IER_RTSDTR); efr &= ~(UART_17158_EFR_RTSDTR); /* Turn off auto Xoff flow control */ ier &= ~(UART_17158_IER_XOFF); if (ch->ch_c_iflag & IXON) efr &= ~(UART_17158_EFR_IXOFF); else efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); /* Turn on table D, with 8 char hi/low watermarks */ writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr); ch->ch_r_watermark = 0; writeb(16, &ch->ch_neo_uart->tfifo); ch->ch_t_tlevel = 16; writeb(16, &ch->ch_neo_uart->rfifo); ch->ch_r_tlevel = 16; writeb(ier, &ch->ch_neo_uart->ier); } static void neo_set_no_output_flow_control(struct jsm_channel *ch) { u8 ier, efr; ier = readb(&ch->ch_neo_uart->ier); efr = readb(&ch->ch_neo_uart->efr); jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n"); /* Turn off auto CTS flow control */ ier &= ~(UART_17158_IER_CTSDSR); efr &= ~(UART_17158_EFR_CTSDSR); /* Turn off auto Xon flow control */ if (ch->ch_c_iflag & IXOFF) efr &= ~(UART_17158_EFR_IXON); else efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON); /* Why? Becuz Exar's spec says we have to zero it out before setting it */ writeb(0, &ch->ch_neo_uart->efr); /* Turn on UART enhanced bits */ writeb(efr, &ch->ch_neo_uart->efr); /* Turn on table D, with 8 char hi/low watermarks */ writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr); ch->ch_r_watermark = 0; writeb(16, &ch->ch_neo_uart->tfifo); ch->ch_t_tlevel = 16; writeb(16, &ch->ch_neo_uart->rfifo); ch->ch_r_tlevel = 16; writeb(ier, &ch->ch_neo_uart->ier); } static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch) { /* if hardware flow control is set, then skip this whole thing */ if (ch->ch_c_cflag & CRTSCTS) return; jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "start\n"); /* Tell UART what start/stop chars it should be looking for */ writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1); writeb(0, &ch->ch_neo_uart->xonchar2); writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1); writeb(0, &ch->ch_neo_uart->xoffchar2); } static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch) { int qleft = 0; u8 linestatus = 0; u8 error_mask = 0; int n = 0; int total = 0; u16 head; u16 tail; if (!ch) return; /* cache head and tail of queue */ head = ch->ch_r_head & RQUEUEMASK; tail = ch->ch_r_tail & RQUEUEMASK; /* Get our cached LSR */ linestatus = ch->ch_cached_lsr; ch->ch_cached_lsr = 0; /* Store how much space we have left in the queue */ if ((qleft = tail - head - 1) < 0) qleft += RQUEUEMASK + 1; /* * If the UART is not in FIFO mode, force the FIFO copy to * NOT be run, by setting total to 0. * * On the other hand, if the UART IS in FIFO mode, then ask * the UART to give us an approximation of data it has RX'ed. */ if (!(ch->ch_flags & CH_FIFO_ENABLED)) total = 0; else { total = readb(&ch->ch_neo_uart->rfifo); /* * EXAR chip bug - RX FIFO COUNT - Fudge factor. * * This resolves a problem/bug with the Exar chip that sometimes * returns a bogus value in the rfifo register. * The count can be any where from 0-3 bytes "off". * Bizarre, but true. */ total -= 3; } /* * Finally, bound the copy to make sure we don't overflow * our own queue... * The byte by byte copy loop below this loop this will * deal with the queue overflow possibility. */ total = min(total, qleft); while (total > 0) { /* * Grab the linestatus register, we need to check * to see if there are any errors in the FIFO. */ linestatus = readb(&ch->ch_neo_uart->lsr); /* * Break out if there is a FIFO error somewhere. * This will allow us to go byte by byte down below, * finding the exact location of the error. */ if (linestatus & UART_17158_RX_FIFO_DATA_ERROR) break; /* Make sure we don't go over the end of our queue */ n = min(((u32) total), (RQUEUESIZE - (u32) head)); /* * Cut down n even further if needed, this is to fix * a problem with memcpy_fromio() with the Neo on the * IBM pSeries platform. * 15 bytes max appears to be the magic number. */ n = min((u32) n, (u32) 12); /* * Since we are grabbing the linestatus register, which * will reset some bits after our read, we need to ensure * we don't miss our TX FIFO emptys. */ if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); linestatus = 0; /* Copy data from uart to the queue */ memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n); /* * Since RX_FIFO_DATA_ERROR was 0, we are guaranteed * that all the data currently in the FIFO is free of * breaks and parity/frame/orun errors. */ memset(ch->ch_equeue + head, 0, n); /* Add to and flip head if needed */ head = (head + n) & RQUEUEMASK; total -= n; qleft -= n; ch->ch_rxcount += n; } /* * Create a mask to determine whether we should * insert the character (if any) into our queue. */ if (ch->ch_c_iflag & IGNBRK) error_mask |= UART_LSR_BI; /* * Now cleanup any leftover bytes still in the UART. * Also deal with any possible queue overflow here as well. */ while (1) { /* * Its possible we have a linestatus from the loop above * this, so we "OR" on any extra bits. */ linestatus |= readb(&ch->ch_neo_uart->lsr); /* * If the chip tells us there is no more data pending to * be read, we can then leave. * But before we do, cache the linestatus, just in case. */ if (!(linestatus & UART_LSR_DR)) { ch->ch_cached_lsr = linestatus; break; } /* No need to store this bit */ linestatus &= ~UART_LSR_DR; /* * Since we are grabbing the linestatus register, which * will reset some bits after our read, we need to ensure * we don't miss our TX FIFO emptys. */ if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) { linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR); ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); } /* * Discard character if we are ignoring the error mask. */ if (linestatus & error_mask) { u8 discard; linestatus = 0; memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1); continue; } /* * If our queue is full, we have no choice but to drop some data. * The assumption is that HWFLOW or SWFLOW should have stopped * things way way before we got to this point. * * I decided that I wanted to ditch the oldest data first, * I hope thats okay with everyone? Yes? Good. */ while (qleft < 1) { jsm_dbg(READ, &ch->ch_bd->pci_dev, "Queue full, dropping DATA:%x LSR:%x\n", ch->ch_rqueue[tail], ch->ch_equeue[tail]); ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK; ch->ch_err_overrun++; qleft++; } memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1); ch->ch_equeue[head] = (u8) linestatus; jsm_dbg(READ, &ch->ch_bd->pci_dev, "DATA/LSR pair: %x %x\n", ch->ch_rqueue[head], ch->ch_equeue[head]); /* Ditch any remaining linestatus value. */ linestatus = 0; /* Add to and flip head if needed */ head = (head + 1) & RQUEUEMASK; qleft--; ch->ch_rxcount++; } /* * Write new final heads to channel structure. */ ch->ch_r_head = head & RQUEUEMASK; ch->ch_e_head = head & EQUEUEMASK; jsm_input(ch); } static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch) { u16 head; u16 tail; int n; int s; int qlen; u32 len_written = 0; struct circ_buf *circ; if (!ch) return; circ = &ch->uart_port.state->xmit; /* No data to write to the UART */ if (uart_circ_empty(circ)) return; /* If port is "stopped", don't send any data to the UART */ if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING)) return; /* * If FIFOs are disabled. Send data directly to txrx register */ if (!(ch->ch_flags & CH_FIFO_ENABLED)) { u8 lsrbits = readb(&ch->ch_neo_uart->lsr); ch->ch_cached_lsr |= lsrbits; if (ch->ch_cached_lsr & UART_LSR_THRE) { ch->ch_cached_lsr &= ~(UART_LSR_THRE); writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx); jsm_dbg(WRITE, &ch->ch_bd->pci_dev, "Tx data: %x\n", circ->buf[circ->tail]); circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1); ch->ch_txcount++; } return; } /* * We have to do it this way, because of the EXAR TXFIFO count bug. */ if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM))) return; n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel; /* cache head and tail of queue */ head = circ->head & (UART_XMIT_SIZE - 1); tail = circ->tail & (UART_XMIT_SIZE - 1); qlen = uart_circ_chars_pending(circ); /* Find minimum of the FIFO space, versus queue length */ n = min(n, qlen); while (n > 0) { s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail; s = min(s, n); if (s <= 0) break; memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s); /* Add and flip queue if needed */ tail = (tail + s) & (UART_XMIT_SIZE - 1); n -= s; ch->ch_txcount += s; len_written += s; } /* Update the final tail */ circ->tail = tail & (UART_XMIT_SIZE - 1); if (len_written >= ch->ch_t_tlevel) ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); if (uart_circ_empty(circ)) uart_write_wakeup(&ch->uart_port); } static void neo_parse_modem(struct jsm_channel *ch, u8 signals) { u8 msignals = signals; jsm_dbg(MSIGS, &ch->ch_bd->pci_dev, "neo_parse_modem: port: %d msignals: %x\n", ch->ch_portnum, msignals); /* Scrub off lower bits. They signify delta's, which I don't care about */ /* Keep DDCD and DDSR though */ msignals &= 0xf8; if (msignals & UART_MSR_DDCD) uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD); if (msignals & UART_MSR_DDSR) uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS); if (msignals & UART_MSR_DCD) ch->ch_mistat |= UART_MSR_DCD; else ch->ch_mistat &= ~UART_MSR_DCD; if (msignals & UART_MSR_DSR) ch->ch_mistat |= UART_MSR_DSR; else ch->ch_mistat &= ~UART_MSR_DSR; if (msignals & UART_MSR_RI) ch->ch_mistat |= UART_MSR_RI; else ch->ch_mistat &= ~UART_MSR_RI; if (msignals & UART_MSR_CTS) ch->ch_mistat |= UART_MSR_CTS; else ch->ch_mistat &= ~UART_MSR_CTS; jsm_dbg(MSIGS, &ch->ch_bd->pci_dev, "Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n", ch->ch_portnum, !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR), !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS), !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS), !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR), !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI), !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD)); } /* Make the UART raise any of the output signals we want up */ static void neo_assert_modem_signals(struct jsm_channel *ch) { if (!ch) return; writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } /* * Flush the WRITE FIFO on the Neo. * * NOTE: Channel lock MUST be held before calling this function! */ static void neo_flush_uart_write(struct jsm_channel *ch) { u8 tmp = 0; int i = 0; if (!ch) return; writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr); for (i = 0; i < 10; i++) { /* Check to see if the UART feels it completely flushed the FIFO. */ tmp = readb(&ch->ch_neo_uart->isr_fcr); if (tmp & UART_FCR_CLEAR_XMIT) { jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "Still flushing TX UART... i: %d\n", i); udelay(10); } else break; } ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); } /* * Flush the READ FIFO on the Neo. * * NOTE: Channel lock MUST be held before calling this function! */ static void neo_flush_uart_read(struct jsm_channel *ch) { u8 tmp = 0; int i = 0; if (!ch) return; writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr); for (i = 0; i < 10; i++) { /* Check to see if the UART feels it completely flushed the FIFO. */ tmp = readb(&ch->ch_neo_uart->isr_fcr); if (tmp & 2) { jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "Still flushing RX UART... i: %d\n", i); udelay(10); } else break; } } /* * No locks are assumed to be held when calling this function. */ static void neo_clear_break(struct jsm_channel *ch) { unsigned long lock_flags; spin_lock_irqsave(&ch->ch_lock, lock_flags); /* Turn break off, and unset some variables */ if (ch->ch_flags & CH_BREAK_SENDING) { u8 temp = readb(&ch->ch_neo_uart->lcr); writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr); ch->ch_flags &= ~(CH_BREAK_SENDING); jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "clear break Finishing UART_LCR_SBC! finished: %lx\n", jiffies); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } spin_unlock_irqrestore(&ch->ch_lock, lock_flags); } /* * Parse the ISR register. */ static void neo_parse_isr(struct jsm_board *brd, u32 port) { struct jsm_channel *ch; u8 isr; u8 cause; unsigned long lock_flags; if (!brd) return; if (port >= brd->maxports) return; ch = brd->channels[port]; if (!ch) return; /* Here we try to figure out what caused the interrupt to happen */ while (1) { isr = readb(&ch->ch_neo_uart->isr_fcr); /* Bail if no pending interrupt */ if (isr & UART_IIR_NO_INT) break; /* * Yank off the upper 2 bits, which just show that the FIFO's are enabled. */ isr &= ~(UART_17158_IIR_FIFO_ENABLED); jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d isr: %x\n", __FILE__, __LINE__, isr); if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) { /* Read data from uart -> queue */ neo_copy_data_from_uart_to_queue(ch); /* Call our tty layer to enforce queue flow control if needed. */ spin_lock_irqsave(&ch->ch_lock, lock_flags); jsm_check_queue_flow_control(ch); spin_unlock_irqrestore(&ch->ch_lock, lock_flags); } if (isr & UART_IIR_THRI) { /* Transfer data (if any) from Write Queue -> UART. */ spin_lock_irqsave(&ch->ch_lock, lock_flags); ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); spin_unlock_irqrestore(&ch->ch_lock, lock_flags); neo_copy_data_from_queue_to_uart(ch); } if (isr & UART_17158_IIR_XONXOFF) { cause = readb(&ch->ch_neo_uart->xoffchar1); jsm_dbg(INTR, &ch->ch_bd->pci_dev, "Port %d. Got ISR_XONXOFF: cause:%x\n", port, cause); /* * Since the UART detected either an XON or * XOFF match, we need to figure out which * one it was, so we can suspend or resume data flow. */ spin_lock_irqsave(&ch->ch_lock, lock_flags); if (cause == UART_17158_XON_DETECT) { /* Is output stopped right now, if so, resume it */ if (brd->channels[port]->ch_flags & CH_STOP) { ch->ch_flags &= ~(CH_STOP); } jsm_dbg(INTR, &ch->ch_bd->pci_dev, "Port %d. XON detected in incoming data\n", port); } else if (cause == UART_17158_XOFF_DETECT) { if (!(brd->channels[port]->ch_flags & CH_STOP)) { ch->ch_flags |= CH_STOP; jsm_dbg(INTR, &ch->ch_bd->pci_dev, "Setting CH_STOP\n"); } jsm_dbg(INTR, &ch->ch_bd->pci_dev, "Port: %d. XOFF detected in incoming data\n", port); } spin_unlock_irqrestore(&ch->ch_lock, lock_flags); } if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) { /* * If we get here, this means the hardware is doing auto flow control. * Check to see whether RTS/DTR or CTS/DSR caused this interrupt. */ cause = readb(&ch->ch_neo_uart->mcr); /* Which pin is doing auto flow? RTS or DTR? */ spin_lock_irqsave(&ch->ch_lock, lock_flags); if ((cause & 0x4) == 0) { if (cause & UART_MCR_RTS) ch->ch_mostat |= UART_MCR_RTS; else ch->ch_mostat &= ~(UART_MCR_RTS); } else { if (cause & UART_MCR_DTR) ch->ch_mostat |= UART_MCR_DTR; else ch->ch_mostat &= ~(UART_MCR_DTR); } spin_unlock_irqrestore(&ch->ch_lock, lock_flags); } /* Parse any modem signal changes */ jsm_dbg(INTR, &ch->ch_bd->pci_dev, "MOD_STAT: sending to parse_modem_sigs\n"); neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr)); } } static inline void neo_parse_lsr(struct jsm_board *brd, u32 port) { struct jsm_channel *ch; int linestatus; unsigned long lock_flags; if (!brd) return; if (port >= brd->maxports) return; ch = brd->channels[port]; if (!ch) return; linestatus = readb(&ch->ch_neo_uart->lsr); jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d port: %d linestatus: %x\n", __FILE__, __LINE__, port, linestatus); ch->ch_cached_lsr |= linestatus; if (ch->ch_cached_lsr & UART_LSR_DR) { /* Read data from uart -> queue */ neo_copy_data_from_uart_to_queue(ch); spin_lock_irqsave(&ch->ch_lock, lock_flags); jsm_check_queue_flow_control(ch); spin_unlock_irqrestore(&ch->ch_lock, lock_flags); } /* * This is a special flag. It indicates that at least 1 * RX error (parity, framing, or break) has happened. * Mark this in our struct, which will tell me that I have *to do the special RX+LSR read for this FIFO load. */ if (linestatus & UART_17158_RX_FIFO_DATA_ERROR) jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d Got an RX error, need to parse LSR\n", __FILE__, __LINE__, port); /* * The next 3 tests should *NOT* happen, as the above test * should encapsulate all 3... At least, thats what Exar says. */ if (linestatus & UART_LSR_PE) { ch->ch_err_parity++; jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. PAR ERR!\n", __FILE__, __LINE__, port); } if (linestatus & UART_LSR_FE) { ch->ch_err_frame++; jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. FRM ERR!\n", __FILE__, __LINE__, port); } if (linestatus & UART_LSR_BI) { ch->ch_err_break++; jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. BRK INTR!\n", __FILE__, __LINE__, port); } if (linestatus & UART_LSR_OE) { /* * Rx Oruns. Exar says that an orun will NOT corrupt * the FIFO. It will just replace the holding register * with this new data byte. So basically just ignore this. * Probably we should eventually have an orun stat in our driver... */ ch->ch_err_overrun++; jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. Rx Overrun!\n", __FILE__, __LINE__, port); } if (linestatus & UART_LSR_THRE) { spin_lock_irqsave(&ch->ch_lock, lock_flags); ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); spin_unlock_irqrestore(&ch->ch_lock, lock_flags); /* Transfer data (if any) from Write Queue -> UART. */ neo_copy_data_from_queue_to_uart(ch); } else if (linestatus & UART_17158_TX_AND_FIFO_CLR) { spin_lock_irqsave(&ch->ch_lock, lock_flags); ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); spin_unlock_irqrestore(&ch->ch_lock, lock_flags); /* Transfer data (if any) from Write Queue -> UART. */ neo_copy_data_from_queue_to_uart(ch); } } /* * neo_param() * Send any/all changes to the line to the UART. */ static void neo_param(struct jsm_channel *ch) { u8 lcr = 0; u8 uart_lcr, ier; u32 baud; int quot; struct jsm_board *bd; bd = ch->ch_bd; if (!bd) return; /* * If baud rate is zero, flush queues, and set mval to drop DTR. */ if ((ch->ch_c_cflag & (CBAUD)) == 0) { ch->ch_r_head = ch->ch_r_tail = 0; ch->ch_e_head = ch->ch_e_tail = 0; neo_flush_uart_write(ch); neo_flush_uart_read(ch); ch->ch_flags |= (CH_BAUD0); ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR); neo_assert_modem_signals(ch); return; } else { int i; unsigned int cflag; static struct { unsigned int rate; unsigned int cflag; } baud_rates[] = { { 921600, B921600 }, { 460800, B460800 }, { 230400, B230400 }, { 115200, B115200 }, { 57600, B57600 }, { 38400, B38400 }, { 19200, B19200 }, { 9600, B9600 }, { 4800, B4800 }, { 2400, B2400 }, { 1200, B1200 }, { 600, B600 }, { 300, B300 }, { 200, B200 }, { 150, B150 }, { 134, B134 }, { 110, B110 }, { 75, B75 }, { 50, B50 }, }; cflag = C_BAUD(ch->uart_port.state->port.tty); baud = 9600; for (i = 0; i < ARRAY_SIZE(baud_rates); i++) { if (baud_rates[i].cflag == cflag) { baud = baud_rates[i].rate; break; } } if (ch->ch_flags & CH_BAUD0) ch->ch_flags &= ~(CH_BAUD0); } if (ch->ch_c_cflag & PARENB) lcr |= UART_LCR_PARITY; if (!(ch->ch_c_cflag & PARODD)) lcr |= UART_LCR_EPAR; /* * Not all platforms support mark/space parity, * so this will hide behind an ifdef. */ #ifdef CMSPAR if (ch->ch_c_cflag & CMSPAR) lcr |= UART_LCR_SPAR; #endif if (ch->ch_c_cflag & CSTOPB) lcr |= UART_LCR_STOP; switch (ch->ch_c_cflag & CSIZE) { case CS5: lcr |= UART_LCR_WLEN5; break; case CS6: lcr |= UART_LCR_WLEN6; break; case CS7: lcr |= UART_LCR_WLEN7; break; case CS8: default: lcr |= UART_LCR_WLEN8; break; } ier = readb(&ch->ch_neo_uart->ier); uart_lcr = readb(&ch->ch_neo_uart->lcr); quot = ch->ch_bd->bd_dividend / baud; if (quot != 0) { writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr); writeb((quot & 0xff), &ch->ch_neo_uart->txrx); writeb((quot >> 8), &ch->ch_neo_uart->ier); writeb(lcr, &ch->ch_neo_uart->lcr); } if (uart_lcr != lcr) writeb(lcr, &ch->ch_neo_uart->lcr); if (ch->ch_c_cflag & CREAD) ier |= (UART_IER_RDI | UART_IER_RLSI); ier |= (UART_IER_THRI | UART_IER_MSI); writeb(ier, &ch->ch_neo_uart->ier); /* Set new start/stop chars */ neo_set_new_start_stop_chars(ch); if (ch->ch_c_cflag & CRTSCTS) neo_set_cts_flow_control(ch); else if (ch->ch_c_iflag & IXON) { /* If start/stop is set to disable, then we should disable flow control */ if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR)) neo_set_no_output_flow_control(ch); else neo_set_ixon_flow_control(ch); } else neo_set_no_output_flow_control(ch); if (ch->ch_c_cflag & CRTSCTS) neo_set_rts_flow_control(ch); else if (ch->ch_c_iflag & IXOFF) { /* If start/stop is set to disable, then we should disable flow control */ if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR)) neo_set_no_input_flow_control(ch); else neo_set_ixoff_flow_control(ch); } else neo_set_no_input_flow_control(ch); /* * Adjust the RX FIFO Trigger level if baud is less than 9600. * Not exactly elegant, but this is needed because of the Exar chip's * delay on firing off the RX FIFO interrupt on slower baud rates. */ if (baud < 9600) { writeb(1, &ch->ch_neo_uart->rfifo); ch->ch_r_tlevel = 1; } neo_assert_modem_signals(ch); /* Get current status of the modem signals now */ neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr)); return; } /* * jsm_neo_intr() * * Neo specific interrupt handler. */ static irqreturn_t neo_intr(int irq, void *voidbrd) { struct jsm_board *brd = voidbrd; struct jsm_channel *ch; int port = 0; int type = 0; int current_port; u32 tmp; u32 uart_poll; unsigned long lock_flags; unsigned long lock_flags2; int outofloop_count = 0; /* Lock out the slow poller from running on this board. */ spin_lock_irqsave(&brd->bd_intr_lock, lock_flags); /* * Read in "extended" IRQ information from the 32bit Neo register. * Bits 0-7: What port triggered the interrupt. * Bits 8-31: Each 3bits indicate what type of interrupt occurred. */ uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET); jsm_dbg(INTR, &brd->pci_dev, "%s:%d uart_poll: %x\n", __FILE__, __LINE__, uart_poll); if (!uart_poll) { jsm_dbg(INTR, &brd->pci_dev, "Kernel interrupted to me, but no pending interrupts...\n"); spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags); return IRQ_NONE; } /* At this point, we have at least SOMETHING to service, dig further... */ current_port = 0; /* Loop on each port */ while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){ tmp = uart_poll; outofloop_count++; /* Check current port to see if it has interrupt pending */ if ((tmp & jsm_offset_table[current_port]) != 0) { port = current_port; type = tmp >> (8 + (port * 3)); type &= 0x7; } else { current_port++; continue; } jsm_dbg(INTR, &brd->pci_dev, "%s:%d port: %x type: %x\n", __FILE__, __LINE__, port, type); /* Remove this port + type from uart_poll */ uart_poll &= ~(jsm_offset_table[port]); if (!type) { /* If no type, just ignore it, and move onto next port */ jsm_dbg(INTR, &brd->pci_dev, "Interrupt with no type! port: %d\n", port); continue; } /* Switch on type of interrupt we have */ switch (type) { case UART_17158_RXRDY_TIMEOUT: /* * RXRDY Time-out is cleared by reading data in the * RX FIFO until it falls below the trigger level. */ /* Verify the port is in range. */ if (port >= brd->nasync) continue; ch = brd->channels[port]; neo_copy_data_from_uart_to_queue(ch); /* Call our tty layer to enforce queue flow control if needed. */ spin_lock_irqsave(&ch->ch_lock, lock_flags2); jsm_check_queue_flow_control(ch); spin_unlock_irqrestore(&ch->ch_lock, lock_flags2); continue; case UART_17158_RX_LINE_STATUS: /* * RXRDY and RX LINE Status (logic OR of LSR[4:1]) */ neo_parse_lsr(brd, port); continue; case UART_17158_TXRDY: /* * TXRDY interrupt clears after reading ISR register for the UART channel. */ /* * Yes, this is odd... * Why would I check EVERY possibility of type of * interrupt, when we know its TXRDY??? * Becuz for some reason, even tho we got triggered for TXRDY, * it seems to be occasionally wrong. Instead of TX, which * it should be, I was getting things like RXDY too. Weird. */ neo_parse_isr(brd, port); continue; case UART_17158_MSR: /* * MSR or flow control was seen. */ neo_parse_isr(brd, port); continue; default: /* * The UART triggered us with a bogus interrupt type. * It appears the Exar chip, when REALLY bogged down, will throw * these once and awhile. * Its harmless, just ignore it and move on. */ jsm_dbg(INTR, &brd->pci_dev, "%s:%d Unknown Interrupt type: %x\n", __FILE__, __LINE__, type); continue; } } spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags); jsm_dbg(INTR, &brd->pci_dev, "finish\n"); return IRQ_HANDLED; } /* * Neo specific way of turning off the receiver. * Used as a way to enforce queue flow control when in * hardware flow control mode. */ static void neo_disable_receiver(struct jsm_channel *ch) { u8 tmp = readb(&ch->ch_neo_uart->ier); tmp &= ~(UART_IER_RDI); writeb(tmp, &ch->ch_neo_uart->ier); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } /* * Neo specific way of turning on the receiver. * Used as a way to un-enforce queue flow control when in * hardware flow control mode. */ static void neo_enable_receiver(struct jsm_channel *ch) { u8 tmp = readb(&ch->ch_neo_uart->ier); tmp |= (UART_IER_RDI); writeb(tmp, &ch->ch_neo_uart->ier); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } static void neo_send_start_character(struct jsm_channel *ch) { if (!ch) return; if (ch->ch_startc != __DISABLED_CHAR) { ch->ch_xon_sends++; writeb(ch->ch_startc, &ch->ch_neo_uart->txrx); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } } static void neo_send_stop_character(struct jsm_channel *ch) { if (!ch) return; if (ch->ch_stopc != __DISABLED_CHAR) { ch->ch_xoff_sends++; writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } } /* * neo_uart_init */ static void neo_uart_init(struct jsm_channel *ch) { writeb(0, &ch->ch_neo_uart->ier); writeb(0, &ch->ch_neo_uart->efr); writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr); /* Clear out UART and FIFO */ readb(&ch->ch_neo_uart->txrx); writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr); readb(&ch->ch_neo_uart->lsr); readb(&ch->ch_neo_uart->msr); ch->ch_flags |= CH_FIFO_ENABLED; /* Assert any signals we want up */ writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr); } /* * Make the UART completely turn off. */ static void neo_uart_off(struct jsm_channel *ch) { /* Turn off UART enhanced bits */ writeb(0, &ch->ch_neo_uart->efr); /* Stop all interrupts from occurring. */ writeb(0, &ch->ch_neo_uart->ier); } static u32 neo_get_uart_bytes_left(struct jsm_channel *ch) { u8 left = 0; u8 lsr = readb(&ch->ch_neo_uart->lsr); /* We must cache the LSR as some of the bits get reset once read... */ ch->ch_cached_lsr |= lsr; /* Determine whether the Transmitter is empty or not */ if (!(lsr & UART_LSR_TEMT)) left = 1; else { ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); left = 0; } return left; } /* Channel lock MUST be held by the calling function! */ static void neo_send_break(struct jsm_channel *ch) { /* * Set the time we should stop sending the break. * If we are already sending a break, toss away the existing * time to stop, and use this new value instead. */ /* Tell the UART to start sending the break */ if (!(ch->ch_flags & CH_BREAK_SENDING)) { u8 temp = readb(&ch->ch_neo_uart->lcr); writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr); ch->ch_flags |= (CH_BREAK_SENDING); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } } /* * neo_send_immediate_char. * * Sends a specific character as soon as possible to the UART, * jumping over any bytes that might be in the write queue. * * The channel lock MUST be held by the calling function. */ static void neo_send_immediate_char(struct jsm_channel *ch, unsigned char c) { if (!ch) return; writeb(c, &ch->ch_neo_uart->txrx); /* flush write operation */ neo_pci_posting_flush(ch->ch_bd); } struct board_ops jsm_neo_ops = { .intr = neo_intr, .uart_init = neo_uart_init, .uart_off = neo_uart_off, .param = neo_param, .assert_modem_signals = neo_assert_modem_signals, .flush_uart_write = neo_flush_uart_write, .flush_uart_read = neo_flush_uart_read, .disable_receiver = neo_disable_receiver, .enable_receiver = neo_enable_receiver, .send_break = neo_send_break, .clear_break = neo_clear_break, .send_start_character = neo_send_start_character, .send_stop_character = neo_send_stop_character, .copy_data_from_queue_to_uart = neo_copy_data_from_queue_to_uart, .get_uart_bytes_left = neo_get_uart_bytes_left, .send_immediate_char = neo_send_immediate_char };