[ipxe-devel] [PATCH] [gdbserial] enable using a second serial port
Noe Rubinstein
nrubinstein at avencall.com
Mon Apr 30 08:34:11 UTC 2012
This patch makes the serial port code more general in order for the
gdbstub command to be able to specify another serial port.
This enables, for example, getting serial output on one serial port
while debugging on the second serial port.
Known bugs:
* It is impossible to choose a speed (and other parameters) for the GDB
serial transport. The default speed is always used.
* When COMPRESERVE is set, the options in the default_serial
structure might be inconsistent the actual parameters.
Signed-off-by: Noe Rubinstein <nrubinstein at avencall.com>
---
src/config/serial.h | 5 --
src/core/gdbserial.c | 36 ++++++++++-
src/core/serial.c | 147 +++++++++++++++++++++++++--------------------
src/include/ipxe/serial.h | 27 +++++++++
4 files changed, 142 insertions(+), 73 deletions(-)
diff --git a/src/config/serial.h b/src/config/serial.h
index 8bb9311..936ef10 100644
--- a/src/config/serial.h
+++ b/src/config/serial.h
@@ -13,11 +13,6 @@
FILE_LICENCE ( GPL2_OR_LATER );
-#define COM1 0x3f8
-#define COM2 0x2f8
-#define COM3 0x3e8
-#define COM4 0x2e8
-
#define COMCONSOLE COM1 /* I/O port address */
/* Keep settings from a previous user of the serial port (e.g. lilo or
diff --git a/src/core/gdbserial.c b/src/core/gdbserial.c
index ed217ad..663ccd5 100644
--- a/src/core/gdbserial.c
+++ b/src/core/gdbserial.c
@@ -19,26 +19,58 @@
FILE_LICENCE ( GPL2_OR_LATER );
#include <assert.h>
+#include <string.h>
+#include <stdio.h>
#include <ipxe/serial.h>
#include <ipxe/gdbstub.h>
#include <ipxe/gdbserial.h>
struct gdb_transport serial_gdb_transport __gdb_transport;
+static struct serial_config port;
+
static size_t gdbserial_recv ( char *buf, size_t len ) {
assert ( len > 0 );
- buf [ 0 ] = serial_getc();
+ buf [ 0 ] = serial_getc_( &port );
return 1;
}
static void gdbserial_send ( const char *buf, size_t len ) {
while ( len-- > 0 ) {
- serial_putc ( *buf++ );
+ serial_putc_ ( &port, *buf++ );
+ }
+}
+
+static int gdbserial_init ( int argc, char **argv ) {
+
+ port = default_serial;
+
+ switch ( argc ) {
+ case 1:
+ if (!strcmp("COM1", argv[0])) port.console = COM1;
+ else if (!strcmp("COM2", argv[0])) port.console = COM2;
+ else if (!strcmp("COM3", argv[0])) port.console = COM3;
+ else if (!strcmp("COM4", argv[0])) port.console = COM4;
+ else {
+ printf("%s is not a serial port. Use COM1, COM2, COM3, or COM4\n", argv[0]);
+ return 1;
+ }
+
+ port.preserve = 0; /* TODO: this should be configurable. */
+ serial_init_(&port);
+ case 0:
+ break;
+ default:
+ printf("Usage: gdbstub serial [port]\n");
+ return 1;
}
+
+ return 0;
}
struct gdb_transport serial_gdb_transport __gdb_transport = {
.name = "serial",
+ .init = gdbserial_init,
.recv = gdbserial_recv,
.send = gdbserial_send,
};
diff --git a/src/core/serial.c b/src/core/serial.c
index a5551b1..6e6b38c 100644
--- a/src/core/serial.c
+++ b/src/core/serial.c
@@ -17,6 +17,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#include <ipxe/init.h>
#include <ipxe/io.h>
#include <unistd.h>
+#include <stdio.h>
#include <ipxe/serial.h>
#include "config/serial.h"
@@ -42,22 +43,26 @@ FILE_LICENCE ( GPL2_OR_LATER );
#define COMSTOP 1
#endif
-#undef UART_BASE
-#define UART_BASE ( COMCONSOLE )
-
-#undef UART_BAUD
-#define UART_BAUD ( COMSPEED )
-
-#if ((115200%UART_BAUD) != 0)
+#if ((115200%COMSPEED) != 0)
#error Bad ttys0 baud rate
#endif
-#define COMBRD (115200/UART_BAUD)
+inline u8 uart_lcs ( struct serial_config *config ) {
+ return ( ( config->data - 5 ) << 0 )
+ | ( ( config->parity ) << 3 )
+ | ( ( config->stop - 1 ) << 2 );
+}
-/* Line Control Settings */
-#define UART_LCS ( ( ( (COMDATA) - 5 ) << 0 ) | \
- ( ( (COMPARITY) ) << 3 ) | \
- ( ( (COMSTOP) - 1 ) << 2 ) )
+struct serial_config default_serial = {
+ .console = COMCONSOLE,
+ .speed = COMSPEED,
+ .data = COMDATA,
+ .parity = COMPARITY,
+ .stop = COMSTOP,
+#ifdef COMPRESERVE
+ .preserve = 1,
+#endif
+};
/* Data */
#define UART_RBR 0x00
@@ -93,19 +98,24 @@ FILE_LICENCE ( GPL2_OR_LATER );
#define uart_writeb(val,addr) outb((val),(addr))
#endif
+void serial_putc ( int ch ) { serial_putc_(&default_serial, ch); }
+int serial_getc ( void ) { return serial_getc_(&default_serial); }
+int serial_ischar ( void ) { return serial_ischar_(&default_serial); }
+static void serial_init ( void ) { return serial_init_(&default_serial); }
+
/*
* void serial_putc(int ch);
- * Write character `ch' to port UART_BASE.
+ * Write character `ch' to port port->console.
*/
-void serial_putc ( int ch ) {
+void serial_putc_ ( struct serial_config *port, int ch ) {
int i;
int status;
i = 1000; /* timeout */
while(--i > 0) {
- status = uart_readb(UART_BASE + UART_LSR);
- if (status & UART_LSR_THRE) {
+ status = uart_readb(port->console + UART_LSR);
+ if (status & UART_LSR_THRE) {
/* TX buffer emtpy */
- uart_writeb(ch, UART_BASE + UART_TBR);
+ uart_writeb(ch, port->console + UART_TBR);
break;
}
mdelay(2);
@@ -114,17 +124,17 @@ void serial_putc ( int ch ) {
/*
* int serial_getc(void);
- * Read a character from port UART_BASE.
+ * Read a character from port port->console.
*/
-int serial_getc ( void ) {
+int serial_getc_ ( struct serial_config *port ) {
int status;
int ch;
do {
- status = uart_readb(UART_BASE + UART_LSR);
+ status = uart_readb(port->console + UART_LSR);
} while((status & 1) == 0);
- ch = uart_readb(UART_BASE + UART_RBR); /* fetch (first) character */
- ch &= 0x7f; /* remove any parity bits we get */
- if (ch == 0x7f) { /* Make DEL... look like BS */
+ ch = uart_readb(port->console + UART_RBR); /* fetch (first) character */
+ ch &= 0x7f; /* remove any parity bits we get */
+ if (ch == 0x7f) { /* Make DEL... look like BS */
ch = 0x08;
}
return ch;
@@ -132,80 +142,85 @@ int serial_getc ( void ) {
/*
* int serial_ischar(void);
- * If there is a character in the input buffer of port UART_BASE,
+ * If there is a character in the input buffer of port port->console,
* return nonzero; otherwise return 0.
*/
-int serial_ischar ( void ) {
+int serial_ischar_ ( struct serial_config *port ) {
int status;
- status = uart_readb(UART_BASE + UART_LSR); /* line status reg; */
- return status & 1; /* rx char available */
+ status = uart_readb(port->console + UART_LSR); /* line status reg; */
+ return status & 1; /* rx char available */
}
/*
* int serial_init(void);
- * Initialize port UART_BASE to speed COMSPEED, line settings 8N1.
+ * Initialize port port->console to speed port->speed, line settings 8N1.
*/
-static void serial_init ( void ) {
+void serial_init_ ( struct serial_config *port ) {
int status;
int divisor, lcs;
- DBG ( "Serial port %#x initialising\n", UART_BASE );
+ DBG ( "Serial port %#x initialising\n", port->console );
- divisor = COMBRD;
- lcs = UART_LCS;
+ if ((115200 % port->speed) != 0) {
+ printf("Bad baud rate %d\n", port->speed);
+ return;
+ }
+ divisor = 115200 / port->speed;
+ lcs = uart_lcs(port);
-#ifdef COMPRESERVE
- lcs = uart_readb(UART_BASE + UART_LCR) & 0x7f;
- uart_writeb(0x80 | lcs, UART_BASE + UART_LCR);
- divisor = (uart_readb(UART_BASE + UART_DLM) << 8) | uart_readb(UART_BASE + UART_DLL);
- uart_writeb(lcs, UART_BASE + UART_LCR);
-#endif
+ if (port->preserve) {
+ lcs = uart_readb(port->console + UART_LCR) & 0x7f;
+ uart_writeb(0x80 | lcs, port->console + UART_LCR);
+ divisor = (uart_readb(port->console + UART_DLM) << 8)
+ | uart_readb(port->console + UART_DLL);
+ uart_writeb(lcs, port->console + UART_LCR);
+ }
- /* Set Baud Rate Divisor to COMSPEED, and test to see if the
+ /* Set Baud Rate Divisor to port->speed, and test to see if the
* serial port appears to be present.
*/
- uart_writeb(0x80 | lcs, UART_BASE + UART_LCR);
- uart_writeb(0xaa, UART_BASE + UART_DLL);
- if (uart_readb(UART_BASE + UART_DLL) != 0xaa) {
- DBG ( "Serial port %#x UART_DLL failed\n", UART_BASE );
+ uart_writeb(0x80 | lcs, port->console + UART_LCR);
+ uart_writeb(0xaa, port->console + UART_DLL);
+ if (uart_readb(port->console + UART_DLL) != 0xaa) {
+ DBG ( "Serial port %#x UART_DLL failed\n", port->console );
goto out;
}
- uart_writeb(0x55, UART_BASE + UART_DLL);
- if (uart_readb(UART_BASE + UART_DLL) != 0x55) {
- DBG ( "Serial port %#x UART_DLL failed\n", UART_BASE );
+ uart_writeb(0x55, port->console + UART_DLL);
+ if (uart_readb(port->console + UART_DLL) != 0x55) {
+ DBG ( "Serial port %#x UART_DLL failed\n", port->console );
goto out;
}
- uart_writeb(divisor & 0xff, UART_BASE + UART_DLL);
- if (uart_readb(UART_BASE + UART_DLL) != (divisor & 0xff)) {
- DBG ( "Serial port %#x UART_DLL failed\n", UART_BASE );
+ uart_writeb(divisor & 0xff, port->console + UART_DLL);
+ if (uart_readb(port->console + UART_DLL) != (divisor & 0xff)) {
+ DBG ( "Serial port %#x UART_DLL failed\n", port->console );
goto out;
}
- uart_writeb(0xaa, UART_BASE + UART_DLM);
- if (uart_readb(UART_BASE + UART_DLM) != 0xaa) {
- DBG ( "Serial port %#x UART_DLM failed\n", UART_BASE );
+ uart_writeb(0xaa, port->console + UART_DLM);
+ if (uart_readb(port->console + UART_DLM) != 0xaa) {
+ DBG ( "Serial port %#x UART_DLM failed\n", port->console );
goto out;
}
- uart_writeb(0x55, UART_BASE + UART_DLM);
- if (uart_readb(UART_BASE + UART_DLM) != 0x55) {
- DBG ( "Serial port %#x UART_DLM failed\n", UART_BASE );
+ uart_writeb(0x55, port->console + UART_DLM);
+ if (uart_readb(port->console + UART_DLM) != 0x55) {
+ DBG ( "Serial port %#x UART_DLM failed\n", port->console );
goto out;
}
- uart_writeb((divisor >> 8) & 0xff, UART_BASE + UART_DLM);
- if (uart_readb(UART_BASE + UART_DLM) != ((divisor >> 8) & 0xff)) {
- DBG ( "Serial port %#x UART_DLM failed\n", UART_BASE );
+ uart_writeb((divisor >> 8) & 0xff, port->console + UART_DLM);
+ if (uart_readb(port->console + UART_DLM) != ((divisor >> 8) & 0xff)) {
+ DBG ( "Serial port %#x UART_DLM failed\n", port->console );
goto out;
}
- uart_writeb(lcs, UART_BASE + UART_LCR);
-
+ uart_writeb(lcs, port->console + UART_LCR);
+
/* disable interrupts */
- uart_writeb(0x0, UART_BASE + UART_IER);
+ uart_writeb(0x0, port->console + UART_IER);
/* disable fifo's */
- uart_writeb(0x00, UART_BASE + UART_FCR);
+ uart_writeb(0x00, port->console + UART_FCR);
/* Set clear to send, so flow control works... */
- uart_writeb((1<<1), UART_BASE + UART_MCR);
+ uart_writeb((1<<1), port->console + UART_MCR);
/* Flush the input buffer. */
@@ -213,9 +228,9 @@ static void serial_init ( void ) {
/* rx buffer reg
* throw away (unconditionally the first time)
*/
- (void) uart_readb(UART_BASE + UART_RBR);
+ (void) uart_readb(port->console + UART_RBR);
/* line status reg */
- status = uart_readb(UART_BASE + UART_LSR);
+ status = uart_readb(port->console + UART_LSR);
} while(status & UART_LSR_DR);
out:
return;
@@ -233,7 +248,7 @@ static void serial_fini ( int flags __unused ) {
*/
i = 10000; /* timeout */
do {
- status = uart_readb(UART_BASE + UART_LSR);
+ status = uart_readb(default_serial.console + UART_LSR);
} while((--i > 0) && !(status & UART_LSR_TEMPT));
/* Don't mark it as disabled; it's still usable */
}
diff --git a/src/include/ipxe/serial.h b/src/include/ipxe/serial.h
index c16e56a..07165c6 100644
--- a/src/include/ipxe/serial.h
+++ b/src/include/ipxe/serial.h
@@ -9,8 +9,35 @@
FILE_LICENCE ( GPL2_OR_LATER );
+#include <stdint.h>
+
+#define COM1 0x3f8
+#define COM2 0x2f8
+#define COM3 0x3e8
+#define COM4 0x2e8
+
+struct serial_config {
+ u32 speed;
+ u16 console;
+ u8 stop;
+ u8 data;
+ enum {
+ PARITY_NONE,
+ PARITY_ODD,
+ PARITY_EVEN,
+ } parity;
+ unsigned preserve:1;
+};
+
+extern struct serial_config default_serial;
+
extern void serial_putc ( int ch );
extern int serial_getc ( void );
extern int serial_ischar ( void );
+extern void serial_putc_ ( struct serial_config *port, int ch );
+extern int serial_getc_ ( struct serial_config *port );
+extern int serial_ischar_ ( struct serial_config *port );
+extern void serial_init_ ( struct serial_config *port );
+
#endif /* _IPXE_SERIAL_H */
--
Noé Rubinstein
Avencall - XiVO IPBX OpenHardware
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