[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>

5 files changed, 139 insertions, 185 deletions

diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c
index 8c37f8f..33f7a3d 100644
--- a/arch/sparc/kernel/process.c
+++ b/arch/sparc/kernel/process.c
@@ -39,6 +39,7 @@
 #include <asm/processor.h>
 #include <asm/psr.h>
 #include <asm/elf.h>
+#include <asm/prom.h>
 #include <asm/unistd.h>
 
 /* 
@@ -150,7 +151,7 @@ void machine_halt(void)
 	local_irq_enable();
 	mdelay(8);
 	local_irq_disable();
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (1);
 	prom_halt();
 	panic("Halt failed!");
@@ -166,7 +167,7 @@ void machine_restart(char * cmd)
 
 	p = strchr (reboot_command, '\n');
 	if (p) *p = 0;
-	if (!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (1);
 	if (cmd)
 		prom_reboot(cmd);
@@ -179,7 +180,8 @@ void machine_restart(char * cmd)
 void machine_power_off(void)
 {
 #ifdef CONFIG_SUN_AUXIO
-	if (auxio_power_register && (!serial_console || scons_pwroff))
+	if (auxio_power_register &&
+	    (strcmp(of_console_device->type, "serial") || scons_pwroff))
 		*auxio_power_register |= AUXIO_POWER_OFF;
 #endif
 	machine_halt();
diff --git a/arch/sparc/kernel/prom.c b/arch/sparc/kernel/prom.c
index 012f983..e3a5376 100644
--- a/arch/sparc/kernel/prom.c
+++ b/arch/sparc/kernel/prom.c
@@ -397,6 +397,135 @@ static struct device_node * __init build_tree(struct device_node *parent, phandl
 	return dp;
 }
 
+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);
+
+extern void restore_current(void);
+
+static void __init of_console_init(void)
+{
+	char *msg = "OF stdout device is: %s\n";
+	struct device_node *dp;
+	unsigned long flags;
+	const char *type;
+	phandle node;
+	int skip, fd;
+
+	of_console_path = prom_early_alloc(256);
+
+	switch (prom_vers) {
+	case PROM_V0:
+	case PROM_SUN4:
+		skip = 0;
+		switch (*romvec->pv_stdout) {
+		case PROMDEV_SCREEN:
+			type = "display";
+			break;
+
+		case PROMDEV_TTYB:
+			skip = 1;
+			/* FALLTHRU */
+
+		case PROMDEV_TTYA:
+			type = "serial";
+			break;
+
+		default:
+			prom_printf("Invalid PROM_V0 stdout value %u\n",
+				    *romvec->pv_stdout);
+			prom_halt();
+		}
+
+		for_each_node_by_type(dp, type) {
+			if (!skip--)
+				break;
+		}
+		if (!dp) {
+			prom_printf("Cannot find PROM_V0 console node.\n");
+			prom_halt();
+		}
+		of_console_device = dp;
+
+		strcpy(of_console_path, dp->full_name);
+		if (!strcmp(type, "serial")) {
+			strcat(of_console_path,
+			       (skip ? ":b" : ":a"));
+		}
+		break;
+
+	default:
+	case PROM_V2:
+	case PROM_V3:
+		fd = *romvec->pv_v2bootargs.fd_stdout;
+
+		spin_lock_irqsave(&prom_lock, flags);
+		node = (*romvec->pv_v2devops.v2_inst2pkg)(fd);
+		restore_current();
+		spin_unlock_irqrestore(&prom_lock, flags);
+
+		if (!node) {
+			prom_printf("Cannot resolve stdout node from "
+				    "instance %08x.\n", fd);
+			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;
+
+		if (prom_vers == PROM_V2) {
+			strcpy(of_console_path, dp->full_name);
+			switch (*romvec->pv_stdout) {
+			case PROMDEV_TTYA:
+				strcat(of_console_path, ":a");
+				break;
+			case PROMDEV_TTYB:
+				strcat(of_console_path, ":b");
+				break;
+			}
+		} else {
+			const char *path;
+
+			dp = of_find_node_by_path("/");
+			path = of_get_property(dp, "stdout-path", NULL);
+			if (!path) {
+				prom_printf("No stdout-path in root node.\n");
+				prom_halt();
+			}
+			strcpy(of_console_path, path);
+		}
+		break;
+	}
+
+	of_console_options = strrchr(of_console_path, ':');
+	if (of_console_options) {
+		of_console_options++;
+		if (*of_console_options == '\0')
+			of_console_options = NULL;
+	}
+
+	prom_printf(msg, of_console_path);
+	printk(msg, of_console_path);
+}
+
 void __init prom_build_devicetree(void)
 {
 	struct device_node **nextp;
@@ -409,6 +538,8 @@ 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/sparc/kernel/setup.c b/arch/sparc/kernel/setup.c
index 64c0ed9..f822838 100644
--- a/arch/sparc/kernel/setup.c
+++ b/arch/sparc/kernel/setup.c
@@ -146,31 +146,6 @@ 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;
-		/* 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) {
@@ -187,9 +162,7 @@ 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.
@@ -341,41 +314,6 @@ void __init setup_arch(char **cmdline_p)
 	smp_setup_cpu_possible_map();
 }
 
-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_I_UNK && odev == PROMDEV_OTTYA) {
-		prom_printf("MrCoffee ttya\n");
-		serial_console = 1;
-	} else if (idev == PROMDEV_I_UNK && odev == PROMDEV_OSCREEN) {
-		serial_console = 0;
-		prom_printf("MrCoffee keyboard\n");
-	} else {
-		prom_printf("Confusing console (idev %d, odev %d)\n",
-		    idev, odev);
-		serial_console = 1;
-	}
-
-	if (serial_console)
-		return add_preferred_console("ttyS", serial_console - 1, NULL);
-
-	return -ENODEV;
-}
-console_initcall(set_preferred_console);
-
 extern char *sparc_cpu_type;
 extern char *sparc_fpu_type;
 
@@ -461,7 +399,6 @@ void sun_do_break(void)
 	prom_cmdline();
 }
 
-int serial_console = -1;
 int stop_a_enabled = 1;
 
 static int __init topology_init(void)
diff --git a/arch/sparc/prom/console.c b/arch/sparc/prom/console.c
index 4e6e41d..8d1cfb0 100644
--- a/arch/sparc/prom/console.c
+++ b/arch/sparc/prom/console.c
@@ -102,119 +102,3 @@ prom_putchar(char c)
 	while(prom_nbputchar(c) == -1) ;
 	return;
 }
-
-/* Query for input device type */
-enum prom_input_device
-prom_query_input_device(void)
-{
-	unsigned long flags;
-	int st_p;
-	char propb[64];
-	char *p;
-	int propl;
-
-	switch(prom_vers) {
-	case PROM_V0:
-	case PROM_V2:
-	case PROM_SUN4:
-	default:
-		switch(*romvec->pv_stdin) {
-		case PROMDEV_KBD:	return PROMDEV_IKBD;
-		case PROMDEV_TTYA:	return PROMDEV_ITTYA;
-		case PROMDEV_TTYB:	return PROMDEV_ITTYB;
-		default:
-			return PROMDEV_I_UNK;
-		};
-	case PROM_V3:
-		spin_lock_irqsave(&prom_lock, flags);
-		st_p = (*romvec->pv_v2devops.v2_inst2pkg)(*romvec->pv_v2bootargs.fd_stdin);
-		restore_current();
-		spin_unlock_irqrestore(&prom_lock, flags);
-		if(prom_node_has_property(st_p, "keyboard"))
-			return PROMDEV_IKBD;
-		if (prom_getproperty(st_p, "name", propb, sizeof(propb)) != -1) {
-			if(strncmp(propb, "keyboard", sizeof("serial")) == 0)
-				return PROMDEV_IKBD;
-		}
-		if (prom_getproperty(st_p, "device_type", propb, sizeof(propb)) != -1) {
-		if(strncmp(propb, "serial", sizeof("serial")))
-			return PROMDEV_I_UNK;
-		}
-		propl = prom_getproperty(prom_root_node, "stdin-path", propb, sizeof(propb));
-		if(propl > 2) {
-			p = propb;
-			while(*p) p++; p -= 2;
-			if(p[0] == ':') {
-				if(p[1] == 'a')
-					return PROMDEV_ITTYA;
-				else if(p[1] == 'b')
-					return PROMDEV_ITTYB;
-			}
-		}
-		return PROMDEV_I_UNK;
-	}
-}
-
-/* Query for output device type */
-
-enum prom_output_device
-prom_query_output_device(void)
-{
-	unsigned long flags;
-	int st_p;
-	char propb[64];
-	char *p;
-	int propl;
-
-	switch(prom_vers) {
-	case PROM_V0:
-	case PROM_SUN4:
-		switch(*romvec->pv_stdin) {
-		case PROMDEV_SCREEN:	return PROMDEV_OSCREEN;
-		case PROMDEV_TTYA:	return PROMDEV_OTTYA;
-		case PROMDEV_TTYB:	return PROMDEV_OTTYB;
-		};
-		break;
-	case PROM_V2:
-	case PROM_V3:
-		spin_lock_irqsave(&prom_lock, flags);
-		st_p = (*romvec->pv_v2devops.v2_inst2pkg)(*romvec->pv_v2bootargs.fd_stdout);
-		restore_current();
-		spin_unlock_irqrestore(&prom_lock, flags);
-		propl = prom_getproperty(st_p, "device_type", propb, sizeof(propb));
-		if (propl == sizeof("display") &&
-			strncmp("display", propb, sizeof("display")) == 0)
-		{
-			return PROMDEV_OSCREEN;
-		}
-		if(prom_vers == PROM_V3) {
-			if(propl >= 0 &&
-			    strncmp("serial", propb, sizeof("serial")) != 0)
-				return PROMDEV_O_UNK;
-			propl = prom_getproperty(prom_root_node, "stdout-path",
-						 propb, sizeof(propb));
-			if(propl == CON_SIZE_JMC &&
-			    strncmp(propb, con_name_jmc, CON_SIZE_JMC) == 0)
-				return PROMDEV_OTTYA;
-			if(propl > 2) {
-				p = propb;
-				while(*p) p++; p-= 2;
-				if(p[0]==':') {
-					if(p[1] == 'a')
-						return PROMDEV_OTTYA;
-					else if(p[1] == 'b')
-						return PROMDEV_OTTYB;
-				}
-			}
-		} else {
-			switch(*romvec->pv_stdin) {
-			case PROMDEV_TTYA:	return PROMDEV_OTTYA;
-			case PROMDEV_TTYB:	return PROMDEV_OTTYB;
-			};
-		}
-		break;
-	default:
-		;
-	};
-	return PROMDEV_O_UNK;
-}
diff --git a/arch/sparc/prom/misc.c b/arch/sparc/prom/misc.c
index 1942c7c..37cff5f 100644
--- a/arch/sparc/prom/misc.c
+++ b/arch/sparc/prom/misc.c
@@ -58,7 +58,7 @@ prom_cmdline(void)
 	extern void install_linux_ticker(void);
 	unsigned long flags;
 
-	if(!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (1);
 	spin_lock_irqsave(&prom_lock, flags);
 	install_obp_ticker();
@@ -69,7 +69,7 @@ prom_cmdline(void)
 #ifdef CONFIG_SUN_AUXIO
 	set_auxio(AUXIO_LED, 0);
 #endif
-	if(!serial_console && prom_palette)
+	if (prom_palette)
 		prom_palette (0);
 }