[SPARC]: Fix serial console device detection.

The current scheme works on static interpretation of text names, which
is wrong.

The output-device setting, for example, must be resolved via an alias
or similar to a full path name to the console device.

Paths also contain an optional set of 'options', which starts with a
colon at the end of the path.  The option area is used to specify
which of two serial ports ('a' or 'b') the path refers to when a
device node drives multiple ports.  'a' is assumed if the option
specification is missing.

This was caught by the UltraSPARC-T1 simulator.  The 'output-device'
property was set to 'ttya' and we didn't pick upon the fact that this
is an OBP alias set to '/virtual-devices/console'.  Instead we saw it
as the first serial console device, instead of the hypervisor console.

The infrastructure is now there to take advantage of this to resolve
the console correctly even in multi-head situations in fbcon too.

Thanks to Greg Onufer for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 71 insertions, 161 deletions

diff --git a/arch/sparc64/kernel/power.c b/arch/sparc64/kernel/power.c
index b00feb0..881a09e 100644
--- a/arch/sparc64/kernel/power.c
+++ b/arch/sparc64/kernel/power.c
@@ -46,7 +46,7 @@ static void (*poweroff_method)(void) = machine_alt_power_off;
 void machine_power_off(void)
 {
 	sstate_poweroff();
-	if (!serial_console || scons_pwroff) {
+	if (strcmp(of_console_device->type, "serial") || scons_pwroff) {
 		if (power_reg) {
 			/* Both register bits seem to have the
 			 * same effect, so until I figure out
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 9355750..fd7899b 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -119,7 +119,7 @@ extern void (*prom_keyboard)(void);
 void machine_halt(void)
 {
 	sstate_halt();
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (1);
 	if (prom_keyboard)
 		prom_keyboard();
@@ -130,7 +130,7 @@ void machine_halt(void)
 void machine_alt_power_off(void)
 {
 	sstate_poweroff();
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette(1);
 	if (prom_keyboard)
 		prom_keyboard();
@@ -145,7 +145,7 @@ void machine_restart(char * cmd)
 	sstate_reboot();
 	p = strchr (reboot_command, '\n');
 	if (p) *p = 0;
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (1);
 	if (prom_keyboard)
 		prom_keyboard();
diff --git a/arch/sparc64/kernel/prom.c b/arch/sparc64/kernel/prom.c
index 2b2017c..f4e0a9a 100644
--- a/arch/sparc64/kernel/prom.c
+++ b/arch/sparc64/kernel/prom.c
@@ -1646,6 +1646,60 @@ static void __init of_fill_in_cpu_data(void)
 	smp_fill_in_sib_core_maps();
 }
 
+struct device_node *of_console_device;
+EXPORT_SYMBOL(of_console_device);
+
+char *of_console_path;
+EXPORT_SYMBOL(of_console_path);
+
+char *of_console_options;
+EXPORT_SYMBOL(of_console_options);
+
+static void __init of_console_init(void)
+{
+	char *msg = "OF stdout device is: %s\n";
+	struct device_node *dp;
+	const char *type;
+	phandle node;
+
+	of_console_path = prom_early_alloc(256);
+	if (prom_ihandle2path(prom_stdout, of_console_path, 256) < 0) {
+		prom_printf("Cannot obtain path of stdout.\n");
+		prom_halt();
+	}
+	of_console_options = strrchr(of_console_path, ':');
+	if (of_console_options) {
+		of_console_options++;
+		if (*of_console_options == '\0')
+			of_console_options = NULL;
+	}
+
+	node = prom_inst2pkg(prom_stdout);
+	if (!node) {
+		prom_printf("Cannot resolve stdout node from "
+			    "instance %08x.\n", prom_stdout);
+		prom_halt();
+	}
+
+	dp = of_find_node_by_phandle(node);
+	type = of_get_property(dp, "device_type", NULL);
+	if (!type) {
+		prom_printf("Console stdout lacks device_type property.\n");
+		prom_halt();
+	}
+
+	if (strcmp(type, "display") && strcmp(type, "serial")) {
+		prom_printf("Console device_type is neither display "
+			    "nor serial.\n");
+		prom_halt();
+	}
+
+	of_console_device = dp;
+
+	prom_printf(msg, of_console_path);
+	printk(msg, of_console_path);
+}
+
 void __init prom_build_devicetree(void)
 {
 	struct device_node **nextp;
@@ -1658,6 +1712,8 @@ void __init prom_build_devicetree(void)
 	allnodes->child = build_tree(allnodes,
 				     prom_getchild(allnodes->node),
 				     &nextp);
+	of_console_init();
+
 	printk("PROM: Built device tree with %u bytes of memory.\n",
 	       prom_early_allocated);
 
diff --git a/arch/sparc64/kernel/setup.c b/arch/sparc64/kernel/setup.c
index aafde3d..0f5be82 100644
--- a/arch/sparc64/kernel/setup.c
+++ b/arch/sparc64/kernel/setup.c
@@ -133,33 +133,6 @@ static void __init process_switch(char c)
 	}
 }
 
-static void __init process_console(char *commands)
-{
-	serial_console = 0;
-	commands += 8;
-	/* Linux-style serial */
-	if (!strncmp(commands, "ttyS", 4))
-		serial_console = simple_strtoul(commands + 4, NULL, 10) + 1;
-	else if (!strncmp(commands, "tty", 3)) {
-		char c = *(commands + 3);
-		/* Solaris-style serial */
-		if (c == 'a' || c == 'b') {
-			serial_console = c - 'a' + 1;
-			prom_printf ("Using /dev/tty%c as console.\n", c);
-		}
-		/* else Linux-style fbcon, not serial */
-	}
-#if defined(CONFIG_PROM_CONSOLE)
-	if (!strncmp(commands, "prom", 4)) {
-		char *p;
-
-		for (p = commands - 8; *p && *p != ' '; p++)
-			*p = ' ';
-		conswitchp = &prom_con;
-	}
-#endif
-}
-
 static void __init boot_flags_init(char *commands)
 {
 	while (*commands) {
@@ -176,9 +149,7 @@ static void __init boot_flags_init(char *commands)
 				process_switch(*commands++);
 			continue;
 		}
-		if (!strncmp(commands, "console=", 8)) {
-			process_console(commands);
-		} else if (!strncmp(commands, "mem=", 4)) {
+		if (!strncmp(commands, "mem=", 4)) {
 			/*
 			 * "mem=XXX[kKmM]" overrides the PROM-reported
 			 * memory size.
@@ -378,44 +349,6 @@ void __init setup_arch(char **cmdline_p)
 	paging_init();
 }
 
-static int __init set_preferred_console(void)
-{
-	int idev, odev;
-
-	/* The user has requested a console so this is already set up. */
-	if (serial_console >= 0)
-		return -EBUSY;
-
-	idev = prom_query_input_device();
-	odev = prom_query_output_device();
-	if (idev == PROMDEV_IKBD && odev == PROMDEV_OSCREEN) {
-		serial_console = 0;
-	} else if (idev == PROMDEV_ITTYA && odev == PROMDEV_OTTYA) {
-		serial_console = 1;
-	} else if (idev == PROMDEV_ITTYB && odev == PROMDEV_OTTYB) {
-		serial_console = 2;
-	} else if (idev == PROMDEV_IRSC && odev == PROMDEV_ORSC) {
-		serial_console = 3;
-	} else if (idev == PROMDEV_IVCONS && odev == PROMDEV_OVCONS) {
-		/* sunhv_console_init() doesn't check the serial_console
-		 * value anyways...
-		 */
-		serial_console = 4;
-		return add_preferred_console("ttyHV", 0, NULL);
-	} else {
-		prom_printf("Inconsistent console: "
-			    "input %d, output %d\n",
-			    idev, odev);
-		prom_halt();
-	}
-
-	if (serial_console)
-		return add_preferred_console("ttyS", serial_console - 1, NULL);
-
-	return -ENODEV;
-}
-console_initcall(set_preferred_console);
-
 /* BUFFER is PAGE_SIZE bytes long. */
 
 extern char *sparc_cpu_type;
@@ -508,5 +441,4 @@ void sun_do_break(void)
 	prom_cmdline();
 }
 
-int serial_console = -1;
 int stop_a_enabled = 1;
diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c
index 719d676..7d36531 100644
--- a/arch/sparc64/kernel/sparc64_ksyms.c
+++ b/arch/sparc64/kernel/sparc64_ksyms.c
@@ -330,7 +330,6 @@ EXPORT_SYMBOL(VISenter);
 
 /* for input/keybdev */
 EXPORT_SYMBOL(sun_do_break);
-EXPORT_SYMBOL(serial_console);
 EXPORT_SYMBOL(stop_a_enabled);
 
 #ifdef CONFIG_DEBUG_BUGVERBOSE
diff --git a/arch/sparc64/prom/console.c b/arch/sparc64/prom/console.c
index 7c25c54..3fafa9a 100644
--- a/arch/sparc64/prom/console.c
+++ b/arch/sparc64/prom/console.c
@@ -73,88 +73,3 @@ prom_puts(const char *s, int len)
 			   P1275_INOUT(3,1),
 			   prom_stdout, s, P1275_SIZE(len));
 }
-
-/* Query for input device type */
-enum prom_input_device
-prom_query_input_device(void)
-{
-	int st_p;
-	char propb[64];
-
-	st_p = prom_inst2pkg(prom_stdin);
-	if(prom_node_has_property(st_p, "keyboard"))
-		return PROMDEV_IKBD;
-	prom_getproperty(st_p, "device_type", propb, sizeof(propb));
-	if(strncmp(propb, "serial", 6))
-		return PROMDEV_I_UNK;
-	/* FIXME: Is there any better way how to find out? */	
-	memset(propb, 0, sizeof(propb));
-	st_p = prom_finddevice ("/options");
-	prom_getproperty(st_p, "input-device", propb, sizeof(propb));
-
-	/*
-	 * If we get here with propb == 'keyboard', we are on ttya, as
-	 * the PROM defaulted to this due to 'no input device'.
-	 */
-	if (!strncmp(propb, "keyboard", 8))
-		return PROMDEV_ITTYA;
-
-	if (!strncmp (propb, "rsc", 3))
-		return PROMDEV_IRSC;
-
-	if (!strncmp (propb, "virtual-console", 3))
-		return PROMDEV_IVCONS;
-
-	if (strncmp (propb, "tty", 3) || !propb[3])
-		return PROMDEV_I_UNK;
-
-	switch (propb[3]) {
-		case 'a': return PROMDEV_ITTYA;
-		case 'b': return PROMDEV_ITTYB;
-		default: return PROMDEV_I_UNK;
-	}
-}
-
-/* Query for output device type */
-
-enum prom_output_device
-prom_query_output_device(void)
-{
-	int st_p;
-	char propb[64];
-	int propl;
-
-	st_p = prom_inst2pkg(prom_stdout);
-	propl = prom_getproperty(st_p, "device_type", propb, sizeof(propb));
-	if (propl >= 0 && propl == sizeof("display") &&
-	    strncmp("display", propb, sizeof("display")) == 0)
-		return PROMDEV_OSCREEN;
-	if(strncmp("serial", propb, 6))
-		return PROMDEV_O_UNK;
-	/* FIXME: Is there any better way how to find out? */	
-	memset(propb, 0, sizeof(propb));
-	st_p = prom_finddevice ("/options");
-	prom_getproperty(st_p, "output-device", propb, sizeof(propb));
-
-	/*
-	 * If we get here with propb == 'screen', we are on ttya, as
-	 * the PROM defaulted to this due to 'no input device'.
-	 */
-	if (!strncmp(propb, "screen", 6))
-		return PROMDEV_OTTYA;
-
-	if (!strncmp (propb, "rsc", 3))
-		return PROMDEV_ORSC;
-
-	if (!strncmp (propb, "virtual-console", 3))
-		return PROMDEV_OVCONS;
-
-	if (strncmp (propb, "tty", 3) || !propb[3])
-		return PROMDEV_O_UNK;
-
-	switch (propb[3]) {
-		case 'a': return PROMDEV_OTTYA;
-		case 'b': return PROMDEV_OTTYB;
-		default: return PROMDEV_O_UNK;
-	}
-}
diff --git a/arch/sparc64/prom/misc.c b/arch/sparc64/prom/misc.c
index 33c5b7d..68c83ad 100644
--- a/arch/sparc64/prom/misc.c
+++ b/arch/sparc64/prom/misc.c
@@ -72,7 +72,7 @@ void prom_cmdline(void)
 
 	local_irq_save(flags);
 
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette(1);
 
 #ifdef CONFIG_SMP
@@ -85,7 +85,7 @@ void prom_cmdline(void)
 	smp_release();
 #endif
 
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette(0);
 
 	local_irq_restore(flags);
diff --git a/arch/sparc64/prom/tree.c b/arch/sparc64/prom/tree.c
index 17b7ecf..b2c5b12 100644
--- a/arch/sparc64/prom/tree.c
+++ b/arch/sparc64/prom/tree.c
@@ -304,3 +304,11 @@ prom_pathtoinode(const char *path)
 	if (node == -1) return 0;
 	return node;
 }
+
+int prom_ihandle2path(int handle, char *buffer, int bufsize)
+{
+	return p1275_cmd("instance-to-path",
+			 P1275_ARG(1,P1275_ARG_OUT_BUF)|
+			 P1275_INOUT(3, 1),
+			 handle, buffer, P1275_SIZE(bufsize));
+}