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-rw-r--r--c/src/lib/libchip/serial/ns16550.c608
1 files changed, 608 insertions, 0 deletions
diff --git a/c/src/lib/libchip/serial/ns16550.c b/c/src/lib/libchip/serial/ns16550.c
new file mode 100644
index 0000000000..dff820bb70
--- /dev/null
+++ b/c/src/lib/libchip/serial/ns16550.c
@@ -0,0 +1,608 @@
+/*
+ * This file contains the TTY driver for the NS16550
+ *
+ * COPYRIGHT (c) 1998 by Radstone Technology
+ *
+ *
+ * THIS FILE IS PROVIDED TO YOU, THE USER, "AS IS", WITHOUT WARRANTY OF ANY
+ * KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK
+ * AS TO THE QUALITY AND PERFORMANCE OF ALL CODE IN THIS FILE IS WITH YOU.
+ *
+ * You are hereby granted permission to use, copy, modify, and distribute
+ * this file, provided that this notice, plus the above copyright notice
+ * and disclaimer, appears in all copies. Radstone Technology will provide
+ * no support for this code.
+ *
+ * This driver uses the termios pseudo driver.
+ */
+
+#include <rtems.h>
+#include <rtems/libio.h>
+#include <stdlib.h>
+
+#include "console.h"
+#include "ns16550_p.h"
+
+/*
+ * Flow control is only supported when using interrupts
+ */
+console_flow ns16550_flow_RTSCTS =
+{
+ ns16550_negate_RTS, /* deviceStopRemoteTx */
+ ns16550_assert_RTS /* deviceStartRemoteTx */
+};
+
+console_flow ns16550_flow_DTRCTS =
+{
+ ns16550_negate_DTR, /* deviceStopRemoteTx */
+ ns16550_assert_DTR /* deviceStartRemoteTx */
+};
+
+console_fns ns16550_fns =
+{
+ ns16550_probe, /* deviceProbe */
+ ns16550_open, /* deviceFirstOpen */
+ ns16550_flush, /* deviceLastClose */
+ NULL, /* deviceRead */
+ ns16550_write_support_int, /* deviceWrite */
+ ns16550_initialize_interrupts, /* deviceInitialize */
+ ns16550_write_polled, /* deviceWritePolled */
+ FALSE, /* deviceOutputUsesInterrupts */
+};
+
+console_fns ns16550_fns_polled =
+{
+ ns16550_probe, /* deviceProbe */
+ ns16550_open, /* deviceFirstOpen */
+ ns16550_close, /* deviceLastClose */
+ ns16550_inbyte_nonblocking_polled, /* deviceRead */
+ ns16550_write_support_polled, /* deviceWrite */
+ ns16550_init, /* deviceInitialize */
+ ns16550_write_polled, /* deviceWritePolled */
+ FALSE, /* deviceOutputUsesInterrupts */
+};
+
+extern void set_vector( rtems_isr_entry, rtems_vector_number, int );
+
+/*
+ * Types for get and set register routines
+ */
+
+typedef unsigned8 (*getRegister_f)(unsigned32 port, unsigned8 register);
+typedef void (*setRegister_f)(
+ unsigned32 port, unsigned8 reg, unsigned8 value);
+/*
+ * Console Device Driver Entry Points
+ */
+static boolean ns16550_probe(int minor)
+{
+ /*
+ * If the configuration dependant probe has located the device then
+ * assume it is there
+ */
+ return(TRUE);
+}
+
+static void ns16550_init(int minor)
+{
+ unsigned32 pNS16550;
+ unsigned8 ucTrash;
+ unsigned8 ucDataByte;
+ unsigned32 ulBaudDivisor;
+ ns16550_context *pns16550Context;
+ setRegister_f setReg;
+ getRegister_f getReg;
+
+ pns16550Context=(ns16550_context *)malloc(sizeof(ns16550_context));
+
+ Console_Port_Data[minor].pDeviceContext=(void *)pns16550Context;
+ pns16550Context->ucModemCtrl=SP_MODEM_IRQ;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+ getReg = Console_Port_Tbl[minor].getRegister;
+
+ /* Clear the divisor latch, clear all interrupt enables,
+ * and reset and
+ * disable the FIFO's.
+ */
+
+ (*setReg)(pNS16550, NS16550_LINE_CONTROL, 0x0);
+ (*setReg)(pNS16550, NS16550_INTERRUPT_ENABLE, 0x0);
+
+ /* Set the divisor latch and set the baud rate. */
+
+ ulBaudDivisor=NS16550_Baud((unsigned32)Console_Port_Tbl[minor].pDeviceParams);
+ ucDataByte = SP_LINE_DLAB;
+ (*setReg)(pNS16550, NS16550_LINE_CONTROL, ucDataByte);
+ (*setReg)(pNS16550, NS16550_TRANSMIT_BUFFER, ulBaudDivisor&0xff);
+ (*setReg)(pNS16550, NS16550_INTERRUPT_ENABLE, (ulBaudDivisor>>8)&0xff);
+
+ /* Clear the divisor latch and set the character size to eight bits */
+ /* with one stop bit and no parity checking. */
+ ucDataByte = EIGHT_BITS;
+ (*setReg)(pNS16550, NS16550_LINE_CONTROL, ucDataByte);
+
+ /* Enable and reset transmit and receive FIFOs. TJA */
+ ucDataByte = SP_FIFO_ENABLE;
+ (*setReg)(pNS16550, NS16550_FIFO_CONTROL, ucDataByte);
+
+ ucDataByte = SP_FIFO_ENABLE | SP_FIFO_RXRST | SP_FIFO_TXRST;
+ (*setReg)(pNS16550, NS16550_FIFO_CONTROL, ucDataByte);
+
+ /*
+ * Disable interrupts
+ */
+ ucDataByte = 0;
+ (*setReg)(pNS16550, NS16550_INTERRUPT_ENABLE, ucDataByte);
+
+ /* Set data terminal ready. */
+ /* And open interrupt tristate line */
+ (*setReg)(pNS16550, NS16550_MODEM_CONTROL,pns16550Context->ucModemCtrl);
+
+ ucTrash = (*getReg)(pNS16550, NS16550_LINE_STATUS );
+ ucTrash = (*getReg)(pNS16550, NS16550_RECEIVE_BUFFER );
+}
+
+static int ns16550_open(
+ int major,
+ int minor,
+ void * arg
+)
+{
+ /*
+ * Assert DTR
+ */
+
+ if(Console_Port_Tbl[minor].pDeviceFlow != &ns16550_flow_DTRCTS) {
+ ns16550_assert_DTR(minor);
+ }
+
+ return(RTEMS_SUCCESSFUL);
+}
+
+static int ns16550_close(
+ int major,
+ int minor,
+ void * arg
+)
+{
+ /*
+ * Negate DTR
+ */
+ if(Console_Port_Tbl[minor].pDeviceFlow != &ns16550_flow_DTRCTS) {
+ ns16550_negate_DTR(minor);
+ }
+
+ return(RTEMS_SUCCESSFUL);
+}
+
+/*
+ * ns16550_write_polled
+ */
+static void ns16550_write_polled(
+ int minor,
+ char cChar
+)
+{
+ unsigned32 pNS16550;
+ unsigned char ucLineStatus;
+ int iTimeout;
+ getRegister_f getReg;
+ setRegister_f setReg;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ getReg = Console_Port_Tbl[minor].getRegister;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * wait for transmitter holding register to be empty
+ */
+ iTimeout=1000;
+ ucLineStatus = (*getReg)(pNS16550, NS16550_LINE_STATUS);
+ while ((ucLineStatus & SP_LSR_THOLD) == 0) {
+ /*
+ * Yield while we wait
+ */
+ if(_System_state_Is_up(_System_state_Get())) {
+ rtems_task_wake_after(RTEMS_YIELD_PROCESSOR);
+ }
+ ucLineStatus = (*getReg)(pNS16550, NS16550_LINE_STATUS);
+ if(!--iTimeout) {
+ break;
+ }
+ }
+
+ /*
+ * transmit character
+ */
+ (*setReg)(pNS16550, NS16550_TRANSMIT_BUFFER, cChar);
+}
+
+/*
+ * These routines provide control of the RTS and DTR lines
+ */
+/*
+ * ns16550_assert_RTS
+ */
+static int ns16550_assert_RTS(int minor)
+{
+ unsigned32 pNS16550;
+ unsigned32 Irql;
+ ns16550_context *pns16550Context;
+ setRegister_f setReg;
+
+ pns16550Context=(ns16550_context *) Console_Port_Data[minor].pDeviceContext;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * Assert RTS
+ */
+ rtems_interrupt_disable(Irql);
+ pns16550Context->ucModemCtrl|=SP_MODEM_RTS;
+ (*setReg)(pNS16550, NS16550_MODEM_CONTROL, pns16550Context->ucModemCtrl);
+ rtems_interrupt_enable(Irql);
+ return 0;
+}
+
+/*
+ * ns16550_negate_RTS
+ */
+static int ns16550_negate_RTS(int minor)
+{
+ unsigned32 pNS16550;
+ unsigned32 Irql;
+ ns16550_context *pns16550Context;
+ setRegister_f setReg;
+
+ pns16550Context=(ns16550_context *) Console_Port_Data[minor].pDeviceContext;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * Negate RTS
+ */
+ rtems_interrupt_disable(Irql);
+ pns16550Context->ucModemCtrl&=~SP_MODEM_RTS;
+ (*setReg)(pNS16550, NS16550_MODEM_CONTROL, pns16550Context->ucModemCtrl);
+ rtems_interrupt_enable(Irql);
+ return 0;
+}
+
+/*
+ * These flow control routines utilise a connection from the local DTR
+ * line to the remote CTS line
+ */
+/*
+ * ns16550_assert_DTR
+ */
+static int ns16550_assert_DTR(int minor)
+{
+ unsigned32 pNS16550;
+ unsigned32 Irql;
+ ns16550_context *pns16550Context;
+ setRegister_f setReg;
+
+ pns16550Context=(ns16550_context *) Console_Port_Data[minor].pDeviceContext;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * Assert DTR
+ */
+ rtems_interrupt_disable(Irql);
+ pns16550Context->ucModemCtrl|=SP_MODEM_DTR;
+ (*setReg)(pNS16550, NS16550_MODEM_CONTROL, pns16550Context->ucModemCtrl);
+ rtems_interrupt_enable(Irql);
+ return 0;
+}
+
+/*
+ * ns16550_negate_DTR
+ */
+static int ns16550_negate_DTR(int minor)
+{
+ unsigned32 pNS16550;
+ unsigned32 Irql;
+ ns16550_context *pns16550Context;
+ setRegister_f setReg;
+
+ pns16550Context=(ns16550_context *) Console_Port_Data[minor].pDeviceContext;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * Negate DTR
+ */
+ rtems_interrupt_disable(Irql);
+ pns16550Context->ucModemCtrl&=~SP_MODEM_DTR;
+ (*setReg)(pNS16550, NS16550_MODEM_CONTROL,pns16550Context->ucModemCtrl);
+ rtems_interrupt_enable(Irql);
+ return 0;
+}
+
+/*
+ * ns16550_isr
+ *
+ * This routine is the console interrupt handler for COM1 and COM2
+ *
+ * Input parameters:
+ * vector - vector number
+ *
+ * Output parameters: NONE
+ *
+ * Return values: NONE
+ */
+
+static void ns16550_process(
+ int minor
+)
+{
+ unsigned32 pNS16550;
+ volatile unsigned8 ucLineStatus;
+ volatile unsigned8 ucInterruptId;
+ char cChar;
+ getRegister_f getReg;
+ setRegister_f setReg;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ getReg = Console_Port_Tbl[minor].getRegister;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ do {
+ /*
+ * Deal with any received characters
+ */
+ while(TRUE) {
+ ucLineStatus = (*getReg)(pNS16550, NS16550_LINE_STATUS);
+ if(~ucLineStatus & SP_LSR_RDY) {
+ break;
+ }
+ cChar = (*getReg)(pNS16550, NS16550_RECEIVE_BUFFER);
+ rtems_termios_enqueue_raw_characters(
+ Console_Port_Data[minor].termios_data,
+ &cChar,
+ 1
+ );
+ }
+
+ while(TRUE) {
+ if(Ring_buffer_Is_empty(&Console_Port_Data[minor].TxBuffer)) {
+ Console_Port_Data[minor].bActive=FALSE;
+ if(Console_Port_Tbl[minor].pDeviceFlow !=&ns16550_flow_RTSCTS) {
+ ns16550_negate_RTS(minor);
+ }
+
+ /*
+ * There is no data to transmit
+ */
+ break;
+ }
+
+ ucLineStatus = (*getReg)(pNS16550, NS16550_LINE_STATUS);
+ if(~ucLineStatus & SP_LSR_THOLD) {
+ /*
+ * We'll get another interrupt when
+ * the transmitter holding reg. becomes
+ * free again
+ */
+ break;
+ }
+
+ Ring_buffer_Remove_character( &Console_Port_Data[minor].TxBuffer, cChar);
+ /*
+ * transmit character
+ */
+ (*setReg)(pNS16550, NS16550_TRANSMIT_BUFFER, cChar);
+ }
+
+ ucInterruptId = (*getReg)(pNS16550, NS16550_INTERRUPT_ID);
+ }
+ while((ucInterruptId&0xf)!=0x1);
+}
+
+static rtems_isr ns16550_isr(
+ rtems_vector_number vector
+)
+{
+ int minor;
+
+ for(minor=0;minor<Console_Port_Count;minor++) {
+ if(vector==Console_Port_Tbl[minor].ulIntVector) {
+ ns16550_process(minor);
+ }
+ }
+}
+
+/*
+ * ns16550_flush
+ */
+static int ns16550_flush(int major, int minor, void *arg)
+{
+ while(!Ring_buffer_Is_empty(&Console_Port_Data[minor].TxBuffer)) {
+ /*
+ * Yield while we wait
+ */
+ if(_System_state_Is_up(_System_state_Get())) {
+ rtems_task_wake_after(RTEMS_YIELD_PROCESSOR);
+ }
+ }
+
+ ns16550_close(major, minor, arg);
+
+ return(RTEMS_SUCCESSFUL);
+}
+
+/*
+ * ns16550_initialize_interrupts
+ *
+ * This routine initializes the console's receive and transmit
+ * ring buffers and loads the appropriate vectors to handle the interrupts.
+ *
+ * Input parameters: NONE
+ *
+ * Output parameters: NONE
+ *
+ * Return values: NONE
+ */
+
+static void ns16550_enable_interrupts(
+ int minor
+)
+{
+ unsigned32 pNS16550;
+ unsigned8 ucDataByte;
+ setRegister_f setReg;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ setReg = Console_Port_Tbl[minor].setRegister;
+
+ /*
+ * Enable interrupts
+ */
+ ucDataByte = SP_INT_RX_ENABLE | SP_INT_TX_ENABLE;
+ (*setReg)(pNS16550, NS16550_INTERRUPT_ENABLE, ucDataByte);
+
+}
+
+static void ns16550_initialize_interrupts(int minor)
+{
+ ns16550_init(minor);
+
+ Ring_buffer_Initialize(&Console_Port_Data[minor].TxBuffer);
+
+ Console_Port_Data[minor].bActive = FALSE;
+
+ set_vector(ns16550_isr, Console_Port_Tbl[minor].ulIntVector, 1);
+
+ ns16550_enable_interrupts(minor);
+}
+
+/*
+ * ns16550_write_support_int
+ *
+ * Console Termios output entry point.
+ *
+ */
+static int ns16550_write_support_int(
+ int minor,
+ const char *buf,
+ int len
+)
+{
+ int i;
+ unsigned32 Irql;
+
+ for(i=0; i<len;) {
+ if(Ring_buffer_Is_full(&Console_Port_Data[minor].TxBuffer)) {
+ if(!Console_Port_Data[minor].bActive) {
+ /*
+ * Wake up the device
+ */
+ rtems_interrupt_disable(Irql);
+ Console_Port_Data[minor].bActive = TRUE;
+ if(Console_Port_Tbl[minor].pDeviceFlow != &ns16550_flow_RTSCTS) {
+ ns16550_assert_RTS(minor);
+ }
+ ns16550_process(minor);
+ rtems_interrupt_enable(Irql);
+ } else {
+ /*
+ * Yield
+ */
+ rtems_task_wake_after(RTEMS_YIELD_PROCESSOR);
+ }
+
+ /*
+ * Wait for ring buffer to empty
+ */
+ continue;
+ }
+ else {
+ Ring_buffer_Add_character( &Console_Port_Data[minor].TxBuffer, buf[i]);
+ i++;
+ }
+ }
+
+ /*
+ * Ensure that characters are on the way
+ */
+ if(!Console_Port_Data[minor].bActive) {
+ /*
+ * Wake up the device
+ */
+ rtems_interrupt_disable(Irql);
+ Console_Port_Data[minor].bActive = TRUE;
+ if(Console_Port_Tbl[minor].pDeviceFlow !=&ns16550_flow_RTSCTS) {
+ ns16550_assert_RTS(minor);
+ }
+ ns16550_process(minor);
+ rtems_interrupt_enable(Irql);
+ }
+
+ return (len);
+}
+
+/*
+ * ns16550_write_support_polled
+ *
+ * Console Termios output entry point.
+ *
+ */
+static int ns16550_write_support_polled(
+ int minor,
+ const char *buf,
+ int len
+)
+{
+ int nwrite = 0;
+
+ /*
+ * poll each byte in the string out of the port.
+ */
+ while (nwrite < len) {
+ /*
+ * transmit character
+ */
+ ns16550_write_polled(minor, *buf++);
+ nwrite++;
+ }
+
+ /*
+ * return the number of bytes written.
+ */
+ return nwrite;
+}
+
+/*
+ * ns16550_inbyte_nonblocking_polled
+ *
+ * Console Termios polling input entry point.
+ */
+
+static int ns16550_inbyte_nonblocking_polled(
+ int minor
+)
+{
+ unsigned32 pNS16550;
+ unsigned char ucLineStatus;
+ char cChar;
+ getRegister_f getReg;
+
+ pNS16550 = Console_Port_Tbl[minor].ulCtrlPort1;
+ getReg = Console_Port_Tbl[minor].getRegister;
+
+ ucLineStatus = (*getReg)(pNS16550, NS16550_LINE_STATUS);
+ if(ucLineStatus & SP_LSR_RDY) {
+ cChar = (*getReg)(pNS16550, NS16550_RECEIVE_BUFFER);
+ return((int)cChar);
+ } else {
+ return(-1);
+ }
+}
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