sh-lite.patch

Linux-2.6.18内核调试工具补丁程序KGDB。

This adds basic support for KGDB on SuperH as well as adding some architecture
specific notes to the DocBook file and converting the 7751 to use this.  I
have tested all combinations of 8250 and SCI(F) ports being used as KGDB and
console that I could (one of each usable to me).

Signed-off-by: Milind Dumbare <[e-mail]>
Signed-off-by: Tom Rini <[e-mail]>

 Documentation/DocBook/kgdb.tmpl |   16
 arch/sh/Kconfig.debug           |   92 --
 arch/sh/Makefile                |    1
 arch/sh/boards/se/7751/setup.c  |  139 ---
 arch/sh/kernel/Makefile         |    2
 arch/sh/kernel/cpu/sh3/ex.S     |    2
 arch/sh/kernel/cpu/sh4/ex.S     |    2
 arch/sh/kernel/entry.S          |   30
 arch/sh/kernel/kgdb-jmp.S       |   32
 arch/sh/kernel/kgdb.c           |  363 +++++++++
 arch/sh/kernel/kgdb_jmp.S       |   33
 arch/sh/kernel/kgdb_stub.c      | 1491 ----------------------------------------
 arch/sh/kernel/setup.c          |   94 --
 arch/sh/kernel/time.c           |    8
 arch/sh/kernel/traps.c          |   20
 arch/sh/mm/extable.c            |    7
 arch/sh/mm/fault-nommu.c        |   14
 arch/sh/mm/fault.c              |   12
 drivers/serial/sh-sci.c         |  300 ++++----
 include/asm-sh/kgdb.h           |  116 ---
 include/asm-sh/system.h         |   40 +
 lib/Kconfig.debug               |    6
 22 files changed, 677 insertions(+), 2143 deletions(-)

Index: linux-2.6.16/Documentation/DocBook/kgdb.tmpl
===================================================================
--- linux-2.6.16.orig/Documentation/DocBook/kgdb.tmpl	2006-04-25 11:27:15.000000000 +0530
+++ linux-2.6.16/Documentation/DocBook/kgdb.tmpl	2006-04-25 11:34:01.000000000 +0530
@@ -124,6 +124,10 @@
     serial driver, pass in: <constant>kgdbwait</constant>.
     </para>
     <para>
+    To specify the values of the SH SCI(F) serial port at boot:
+    <constant>kgdbsci=0,115200</constant>.
+    </para>
+    <para>
     To specify the values of the serial port at boot:
     <constant>kgdb8250=io,3f8,115200,3</constant>.
     On IA64 this could also be:
@@ -181,6 +185,18 @@
     application program.
     </para>
   </chapter>
+  <chapter id="ArchitectureNotes">
+    <title>Architecture specific notes</title>
+      <para>
+      SuperH: The NMI switch found on some boards can be used to trigger an
+      initial breakpoint.  Subsequent triggers do nothing.  If console
+      is enabled on the SCI(F) serial port, and that is the port being used
+      for KGDB, then you must trigger a breakpoint via sysrq, NMI, or
+      some other method prior to connecting, or echo a control-c to the
+      serial port.  Also, to use the SCI(F) port for KGDB, the
+      <symbol>CONFIG_SERIAL_SH_SCI</symbol> driver must be enabled.
+      </para>
+  </chapter>
   <chapter id="CommonBackEndReq">
     <title>The common backend (required)</title>
       <para>
Index: linux-2.6.16/drivers/serial/sh-sci.c
===================================================================
--- linux-2.6.16.orig/drivers/serial/sh-sci.c	2006-03-20 11:23:29.000000000 +0530
+++ linux-2.6.16/drivers/serial/sh-sci.c	2006-04-25 11:38:27.000000000 +0530
@@ -43,6 +43,7 @@
 #include <linux/console.h>
 #include <linux/bitops.h>
 #include <linux/generic_serial.h>
+#include <linux/kgdb.h>
 
 #ifdef CONFIG_CPU_FREQ
 #include <linux/notifier.h>
@@ -68,14 +69,16 @@
 
 #include "sh-sci.h"
 
-#ifdef CONFIG_SH_KGDB
-#include <asm/kgdb.h>
-
-static int kgdb_get_char(struct sci_port *port);
-static void kgdb_put_char(struct sci_port *port, char c);
-static void kgdb_handle_error(struct sci_port *port);
-static struct sci_port *kgdb_sci_port;
-#endif /* CONFIG_SH_KGDB */
+#ifdef CONFIG_KGDB_SH_SCI
+/* Speed of the UART. */
+static int kgdbsci_baud = CONFIG_KGDB_BAUDRATE
+
+/* Index of the UART, matches ttySCX naming. */
+static int kgdbsci_ttySC = CONFIG_KGDB_PORT_NUM;
+
+/* Make life easier on us. */
+#define KGDBPORT	sci_ports[kgdbsci_ttySC]
+#endif /* CONFIG_KGDB_SH_SCI */
 
 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
 static struct sci_port *serial_console_port = 0;
@@ -88,20 +91,17 @@
 static void sci_stop_rx(struct uart_port *port);
 static int sci_request_irq(struct sci_port *port);
 static void sci_free_irq(struct sci_port *port);
+static void sci_set_termios(struct uart_port *port, struct termios *termios,
+			struct termios *old);
+static int kgdbsci_init(void);
 
 static struct sci_port sci_ports[];
 static struct uart_driver sci_uart_driver;
 
 #define SCI_NPORTS sci_uart_driver.nr
 
-#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
-
-static void handle_error(struct uart_port *port)
-{				/* Clear error flags */
-	sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
-}
-
-static int get_char(struct uart_port *port)
+#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_KGDB_SH_SCI)
+static int get_char_for_gdb(struct uart_port *port)
 {
 	unsigned long flags;
 	unsigned short status;
@@ -111,7 +111,8 @@
         do {
 		status = sci_in(port, SCxSR);
 		if (status & SCxSR_ERRORS(port)) {
-			handle_error(port);
+			/* Clear error flags. */
+			sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
 			continue;
 		}
 	} while (!(status & SCxSR_RDxF(port)));
@@ -122,21 +123,7 @@
 
 	return c;
 }
-
-/* Taken from sh-stub.c of GDB 4.18 */
-static const char hexchars[] = "0123456789abcdef";
-
-static __inline__ char highhex(int  x)
-{
-	return hexchars[(x >> 4) & 0xf];
-}
-
-static __inline__ char lowhex(int  x)
-{
-	return hexchars[x & 0xf];
-}
-
-#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
+#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_KGDB_SH_SCI */
 
 /*
  * Send the packet in buffer.  The host gets one chance to read it.
@@ -168,21 +155,14 @@
 	const unsigned char *p = buffer;
 	int i;
 
-#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
-	int checksum;
-	int usegdb=0;
-
 #ifdef CONFIG_SH_STANDARD_BIOS
+	int checksum;
+	 const char hexchars[] = "0123456789abcdef";
+	
 	/* This call only does a trap the first time it is
 	 * called, and so is safe to do here unconditionally
 	 */
-	usegdb |= sh_bios_in_gdb_mode();
-#endif
-#ifdef CONFIG_SH_KGDB
-	usegdb |= (kgdb_in_gdb_mode && (port == kgdb_sci_port));
-#endif
-
-	if (usegdb) {
+	if (sh_bios_in_gdb_mode()) {
 	    /*  $<packet info>#<checksum>. */
 	    do {
 		unsigned char c;
@@ -194,18 +174,18 @@
 			int h, l;
 
 			c = *p++;
-			h = highhex(c);
-			l = lowhex(c);
+			h = hexchars[c >> 4];
+			l = hexchars[c % 16];
 			put_char(port, h);
 			put_char(port, l);
 			checksum += h + l;
 		}
 		put_char(port, '#');
-		put_char(port, highhex(checksum));
-		put_char(port, lowhex(checksum));
+		put_char(port, hexchars[checksum >> 4]);
+		put_char(port, hexchars[checksum & 16]);
 	    } while  (get_char(port) != '+');
 	} else
-#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
+#endif /* CONFIG_SH_STANDARD_BIOS */
 	for (i=0; i<count; i++) {
 		if (*p == 10)
 			put_char(port, '\r');
@@ -215,90 +195,163 @@
 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
 
 
-#ifdef CONFIG_SH_KGDB
-
-/* Is the SCI ready, ie is there a char waiting? */
-static int kgdb_is_char_ready(struct sci_port *port)
+#ifdef CONFIG_KGDB_SH_SCI
+static int kgdbsci_read_char(void)
 {
-        unsigned short status = sci_in(port, SCxSR);
-
-        if (status & (SCxSR_ERRORS(port) | SCxSR_BRK(port)))
-                kgdb_handle_error(port);
-
-        return (status & SCxSR_RDxF(port));
+	return get_char_for_gdb(&KGDBPORT.port);
 }
 
-/* Write a char */
-static void kgdb_put_char(struct sci_port *port, char c)
+/* Called from kgdbstub.c to put a character, just a wrapper */
+static void kgdbsci_write_char(int c)
 {
-        unsigned short status;
-
-        do
-                status = sci_in(port, SCxSR);
-        while (!(status & SCxSR_TDxE(port)));
+	unsigned short status;
 
-        sci_out(port, SCxTDR, c);
-        sci_in(port, SCxSR);    /* Dummy read */
-        sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
+	do
+		status = sci_in(&KGDBPORT.port, SCxSR);
+	while (!(status & SCxSR_TDxE(&KGDBPORT.port)));
+
+	sci_out(&KGDBPORT.port, SCxTDR, c);
+	sci_in(&KGDBPORT.port, SCxSR);	/* Dummy read */
+	sci_out(&KGDBPORT.port, SCxSR, SCxSR_TDxE_CLEAR(&KGDBPORT.port));
 }
 
-/* Get a char if there is one, else ret -1 */
-static int kgdb_get_char(struct sci_port *port)
+#ifndef CONFIG_SERIAL_SH_SCI_CONSOLE
+/* If we don't have console, we never hookup IRQs.  But we need to
+ * hookup one so that we can interrupt the system.
+ */
+static irqreturn_t kgdbsci_rx_interrupt(int irq, void *ptr,
+		struct pt_regs *regs)
 {
-        int c;
+	struct uart_port *port = ptr;
 
-        if (kgdb_is_char_ready(port) == 0)
-                c = -1;
-        else {
-                c = sci_in(port, SCxRDR);
-                sci_in(port, SCxSR);    /* Dummy read */
-                sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
-        }
+	if (!(sci_in(port, SCxSR) & SCxSR_RDxF(port)))
+		return IRQ_NONE;
 
-        return c;
-}
-
-/* Called from kgdbstub.c to get a character, i.e. is blocking */
-static int kgdb_sci_getchar(void)
-{
-        volatile int c;
+	if (kgdb_io_ops.init != kgdbsci_init) {
+		/* Throw away the data if another I/O routine is active */
+		get_char_for_gdb(&KGDBPORT.port);
+	} else
+		/* We've got an interrupt, so go ahead and call breakpoint() */
+		breakpoint();
 
-        /* Keep trying to read a character, this could be neater */
-        while ((c = kgdb_get_char(kgdb_sci_port)) < 0);
+	sci_in(port, SCxSR); /* dummy read */
+	sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
 
-        return c;
+	return IRQ_HANDLED;
 }
 
-/* Called from kgdbstub.c to put a character, just a wrapper */
-static void kgdb_sci_putchar(int c)
+static irqreturn_t kgdbsci_mpxed_interrupt(int irq, void *ptr,
+		struct pt_regs *regs)
 {
+        unsigned short ssr_status, scr_status;
+        struct uart_port *port = ptr;
+
+        ssr_status = sci_in(port,SCxSR);
+        scr_status = sci_in(port,SCSCR);
+
+	/* Rx Interrupt */
+        if ((ssr_status&0x0002) && (scr_status&0x0040))
+		kgdbsci_rx_interrupt(irq, ptr, regs);
 
-        kgdb_put_char(kgdb_sci_port, c);
+	return IRQ_HANDLED;
 }
 
-/* Clear any errors on the SCI */
-static void kgdb_handle_error(struct sci_port *port)
+static void __init kgdbsci_lateinit(void)
 {
-        sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));  /* Clear error flags */
+	if (KGDBPORT.irqs[0] == KGDBPORT.irqs[1]) {
+		if (!KGDBPORT.irqs[0]) {
+			printk(KERN_ERR "kgdbsci: Cannot allocate irq.\n");
+			return;
+		}
+		if (request_irq(KGDBPORT.irqs[0], kgdbsci_mpxed_interrupt,
+					SA_INTERRUPT, "kgdbsci",
+					&KGDBPORT.port)) {
+			printk(KERN_ERR "kgdbsci: Cannot allocate irq.\n");
+			return;
+		}
+	} else {
+		if (KGDBPORT.irqs[1])
+			request_irq(KGDBPORT.irqs[1],
+					kgdbsci_rx_interrupt, SA_INTERRUPT,
+					"kgdbsci", &KGDBPORT.port);
+	}
 }
+#endif
 
-/* Breakpoint if there's a break sent on the serial port */
-static void kgdb_break_interrupt(int irq, void *ptr, struct pt_regs *regs)
+/*
+ * We use the normal init routine to setup the port, so we can't be
+ * in here too early.
+ */
+static int kgdbsci_init(void)
 {
-        struct sci_port *port = ptr;
-        unsigned short status = sci_in(port, SCxSR);
+	struct termios termios;
 
-        if (status & SCxSR_BRK(port)) {
+	memset(&termios, 0, sizeof(struct termios));
 
-                /* Break into the debugger if a break is detected */
-                BREAKPOINT();
+	termios.c_cflag = CREAD | HUPCL | CLOCAL | CS8;
+	switch (kgdbsci_baud) {
+	case 9600:
+		termios.c_cflag |= B9600;
+		break;
+	case 19200:
+		termios.c_cflag |= B19200;
+		break;
+	case 38400:
+		termios.c_cflag |= B38400;
+		break;
+	case 57600:
+		termios.c_cflag |= B57600;
+		break;
+	case 115200:
+		termios.c_cflag |= B115200;
+		break;
+	}
+	sci_set_termios(&KGDBPORT.port, &termios, NULL);
 
-                /* Clear */
-                sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
-        }
+	return 0;
 }
 
-#endif /* CONFIG_SH_KGDB */
+struct kgdb_io kgdb_io_ops = {
+	.read_char = kgdbsci_read_char,
+	.write_char = kgdbsci_write_char,
+	.init = kgdbsci_init,
+#ifndef CONFIG_SERIAL_SH_SCI_CONSOLE
+	.late_init = kgdbsci_lateinit,
+#else /* ! CONFIG_SERIAL_SH_SCI_CONSOLE */
+	.late_init = NULL,
+#endif /* ! CONFIG_SERIAL_SH_SCI_CONSOLE */
+	.pre_exception = NULL,
+	.post_exception = NULL
+};
+
+/*
+ * Syntax for this cmdline option is "kgdbsci=ttyno,baudrate".
+ */
+static int __init
+kgdbsci_opt(char *str)
+{
+	/* We might have anywhere from 1 to 3 ports. */
+	if (*str < '0' || *str > SCI_NPORTS + '0')
+		 goto errout;
+	kgdbsci_ttySC = *str - '0';
+	str++;
+	if (*str != ',')
+		 goto errout;
+	str++;
+	kgdbsci_baud = simple_strtoul(str, &str, 10);
+	if (kgdbsci_baud != 9600 && kgdbsci_baud != 19200 &&
+	    kgdbsci_baud != 38400 && kgdbsci_baud != 57600 &&
+	    kgdbsci_baud != 115200)
+		 goto errout;
+
+	return 0;
+
+errout:
+	printk(KERN_ERR "Invalid syntax for option kgdbsci=\n");
+	return 1;
+}
+__setup("kgdbsci", kgdbsci_opt);
+#endif /* CONFIG_KGDB_SH_SCI */
 
 #if defined(__H8300S__)
 enum { sci_disable, sci_enable };
@@ -556,6 +609,16 @@
 					continue;
 				}
 
+#ifdef CONFIG_KGDB_SH_SCI
+				/* We assume that a ^C on the port KGDB
+				 * is using means that KGDB wants to
+				 * interrupt the running system.
+				 */
+				if (port->line == KGDBPORT.port.line &&
+						c == 3)
+					breakpoint();
+#endif
+
 				/* Store data and status */
 				if (status&SCxSR_FER(port)) {
 					flag = TTY_FRAME;
@@ -1619,6 +1682,7 @@
 console_initcall(sci_console_init);
 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
 
+#if 0
 #ifdef CONFIG_SH_KGDB
 /*
  * FIXME: Most of this can go away.. at the moment, we rely on
@@ -1664,30 +1728,9 @@
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 #endif /* CONFIG_SH_KGDB */
+#endif /* 0 */
 
-#ifdef CONFIG_SH_KGDB_CONSOLE
-static struct console kgdb_console = {
-        .name		= "ttySC",
-        .write		= kgdb_console_write,
-        .setup		= kgdb_console_setup,
-        .flags		= CON_PRINTBUFFER | CON_ENABLED,
-        .index		= -1,
-	.data		= &sci_uart_driver,
-};
-
-/* Register the KGDB console so we get messages (d'oh!) */
-static int __init kgdb_console_init(void)
-{
-	register_console(&kgdb_console);
-	return 0;
-}
-
-console_initcall(kgdb_console_init);
-#endif /* CONFIG_SH_KGDB_CONSOLE */
-
-#if defined(CONFIG_SH_KGDB_CONSOLE)
-#define SCI_CONSOLE	&kgdb_console
-#elif defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
+#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
 #define SCI_CONSOLE	&serial_console
 #else
 #define SCI_CONSOLE	0
@@ -1761,4 +1804,3 @@
 
 module_init(sci_init);
 module_exit(sci_exit);