[PATCH] powerpc: serial port discovery (#2)

This moves the discovery of legacy serial ports to a separate file,
makes it common to ppc32 and ppc64, and reworks it to use the new OF
address translators to get to the ports early. This new version can also
detect some PCI serial cards using legacy chips and will probably match
those discovered port with the default console choice.

Only ppc64 gets udbg still yet, unifying udbg isn't finished yet.

It also adds some speed-probing code to udbg so that the default console
can come up at the same speed it was set to by the firmware.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/kernel/Makefile

@@ -33,10 +33,6 @@ obj-$(CONFIG_LPARCFG)		+= lparcfg.o
 obj-$(CONFIG_IBMVIO)		+= vio.o
 obj-$(CONFIG_IBMEBUS)           += ibmebus.o
 obj-$(CONFIG_GENERIC_TBSYNC)	+= smp-tbsync.o
-obj-$(CONFIG_PPC_PSERIES)	+= udbg_16550.o
-obj-$(CONFIG_PPC_MAPLE)		+= udbg_16550.o
-udbgscc-$(CONFIG_PPC64)		:= udbg_scc.o
-obj-$(CONFIG_PPC_PMAC)		+= $(udbgscc-y)
 obj64-$(CONFIG_PPC_MULTIPLATFORM) += nvram_64.o
 
 ifeq ($(CONFIG_PPC_MERGE),y)
@@ -59,14 +55,15 @@ obj-$(CONFIG_BOOTX_TEXT)	+= btext.o
 obj-$(CONFIG_6xx)		+= idle_6xx.o
 obj-$(CONFIG_SMP)		+= smp.o
 obj-$(CONFIG_KPROBES)		+= kprobes.o
-
+obj-$(CONFIG_PPC_MULTIPLATFORM) += legacy_serial.o
+obj64-$(CONFIG_PPC_MULTIPLATFORM) += udbg_16550.o
+obj64-$(CONFIG_PPC_PMAC)	+= udbg_scc.o
 module-$(CONFIG_PPC64)		+= module_64.o
 obj-$(CONFIG_MODULES)		+= $(module-y)
 
 pci64-$(CONFIG_PPC64)		+= pci_64.o pci_dn.o pci_iommu.o \
 				   pci_direct_iommu.o iomap.o
 obj-$(CONFIG_PCI)		+= $(pci64-y)
-
 kexec-$(CONFIG_PPC64)		:= machine_kexec_64.o
 kexec-$(CONFIG_PPC32)		:= machine_kexec_32.o
 obj-$(CONFIG_KEXEC)		+= machine_kexec.o $(kexec-y)

arch/powerpc/kernel/pci_64.c

@@ -1223,6 +1223,7 @@ void __devinit pcibios_fixup_device_resources(struct pci_dev *dev,
 }
 EXPORT_SYMBOL(pcibios_fixup_device_resources);
 
+
 static void __devinit do_bus_setup(struct pci_bus *bus)
 {
 	struct pci_dev *dev;
@@ -1306,6 +1307,20 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
 	*end = rsrc->end + offset;
 }
 
+struct pci_controller* pci_find_hose_for_OF_device(struct device_node* node)
+{
+	if (!have_of)
+		return NULL;
+	while(node) {
+		struct pci_controller *hose, *tmp;
+		list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
+			if (hose->arch_data == node)
+				return hose;
+		node = node->parent;
+	}
+	return NULL;
+}
+
 #endif /* CONFIG_PPC_MULTIPLATFORM */
 
 

arch/powerpc/kernel/setup-common.c

@@ -294,129 +294,6 @@ struct seq_operations cpuinfo_op = {
 	.show =	show_cpuinfo,
 };
 
-#ifdef CONFIG_PPC_MULTIPLATFORM
-static int __init set_preferred_console(void)
-{
-	struct device_node *prom_stdout = NULL;
-	char *name;
-	u32 *spd;
-	int offset = 0;
-
-	DBG(" -> set_preferred_console()\n");
-
-	/* The user has requested a console so this is already set up. */
-	if (strstr(saved_command_line, "console=")) {
-		DBG(" console was specified !\n");
-		return -EBUSY;
-	}
-
-	if (!of_chosen) {
-		DBG(" of_chosen is NULL !\n");
-		return -ENODEV;
-	}
-	/* We are getting a weird phandle from OF ... */
-	/* ... So use the full path instead */
-	name = (char *)get_property(of_chosen, "linux,stdout-path", NULL);
-	if (name == NULL) {
-		DBG(" no linux,stdout-path !\n");
-		return -ENODEV;
-	}
-	prom_stdout = of_find_node_by_path(name);
-	if (!prom_stdout) {
-		DBG(" can't find stdout package %s !\n", name);
-		return -ENODEV;
-	}	
-	DBG("stdout is %s\n", prom_stdout->full_name);
-
-	name = (char *)get_property(prom_stdout, "name", NULL);
-	if (!name) {
-		DBG(" stdout package has no name !\n");
-		goto not_found;
-	}
-	spd = (u32 *)get_property(prom_stdout, "current-speed", NULL);
-
-	if (0)
-		;
-#ifdef CONFIG_SERIAL_8250_CONSOLE
-	else if (strcmp(name, "serial") == 0) {
-		int i;
-		u32 *reg = (u32 *)get_property(prom_stdout, "reg", &i);
-		if (i > 8) {
-			switch (reg[1]) {
-				case 0x3f8:
-					offset = 0;
-					break;
-				case 0x2f8:
-					offset = 1;
-					break;
-				case 0x898:
-					offset = 2;
-					break;
-				case 0x890:
-					offset = 3;
-					break;
-				default:
-					/* We dont recognise the serial port */
-					goto not_found;
-			}
-		}
-	}
-#endif /* CONFIG_SERIAL_8250_CONSOLE */
-#ifdef CONFIG_PPC_PSERIES
-	else if (strcmp(name, "vty") == 0) {
- 		u32 *reg = (u32 *)get_property(prom_stdout, "reg", NULL);
- 		char *compat = (char *)get_property(prom_stdout, "compatible", NULL);
-
- 		if (reg && compat && (strcmp(compat, "hvterm-protocol") == 0)) {
- 			/* Host Virtual Serial Interface */
- 			switch (reg[0]) {
- 				case 0x30000000:
- 					offset = 0;
- 					break;
- 				case 0x30000001:
- 					offset = 1;
- 					break;
- 				default:
-					goto not_found;
- 			}
-			of_node_put(prom_stdout);
-			DBG("Found hvsi console at offset %d\n", offset);
- 			return add_preferred_console("hvsi", offset, NULL);
- 		} else {
- 			/* pSeries LPAR virtual console */
-			of_node_put(prom_stdout);
-			DBG("Found hvc console\n");
- 			return add_preferred_console("hvc", 0, NULL);
- 		}
-	}
-#endif /* CONFIG_PPC_PSERIES */
-#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
-	else if (strcmp(name, "ch-a") == 0)
-		offset = 0;
-	else if (strcmp(name, "ch-b") == 0)
-		offset = 1;
-#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
-	else
-		goto not_found;
-	of_node_put(prom_stdout);
-
-	DBG("Found serial console at ttyS%d\n", offset);
-
-	if (spd) {
-		static char __initdata opt[16];
-		sprintf(opt, "%d", *spd);
-		return add_preferred_console("ttyS", offset, opt);
-	} else
-		return add_preferred_console("ttyS", offset, NULL);
-
- not_found:
-	DBG("No preferred console found !\n");
-	of_node_put(prom_stdout);
-	return -ENODEV;
-}
-console_initcall(set_preferred_console);
-#endif /* CONFIG_PPC_MULTIPLATFORM */
-
 void __init check_for_initrd(void)
 {
 #ifdef CONFIG_BLK_DEV_INITRD

arch/powerpc/kernel/setup_32.c

@@ -39,6 +39,7 @@
 #include <asm/nvram.h>
 #include <asm/xmon.h>
 #include <asm/time.h>
+#include <asm/serial.h>
 
 #include "setup.h"
 
@@ -282,6 +283,13 @@ void __init setup_arch(char **cmdline_p)
 
 	unflatten_device_tree();
 	check_for_initrd();
+
+	if (ppc_md.init_early)
+		ppc_md.init_early();
+
+#ifdef CONFIG_PPC_MULTIPLATFORM
+	find_legacy_serial_ports();
+#endif
 	finish_device_tree();
 
 	smp_setup_cpu_maps();

arch/powerpc/kernel/setup_64.c

@@ -459,6 +459,15 @@ void __init setup_system(void)
 	 */
 	ppc_md.init_early();
 
+ 	/*
+	 * We can discover serial ports now since the above did setup the
+	 * hash table management for us, thus ioremap works. We do that early
+	 * so that further code can be debugged
+	 */
+#ifdef CONFIG_PPC_MULTIPLATFORM
+	find_legacy_serial_ports();
+#endif
+
 	/*
 	 * "Finish" the device-tree, that is do the actual parsing of
 	 * some of the properties like the interrupt map
@@ -657,187 +666,6 @@ void ppc64_terminate_msg(unsigned int src, const char *msg)
 	printk("[terminate]%04x %s\n", src, msg);
 }
 
-#ifndef CONFIG_PPC_ISERIES
-/*
- * This function can be used by platforms to "find" legacy serial ports.
- * It works for "serial" nodes under an "isa" node, and will try to
- * respect the "ibm,aix-loc" property if any. It works with up to 8
- * ports.
- */
-
-#define MAX_LEGACY_SERIAL_PORTS	8
-static struct plat_serial8250_port serial_ports[MAX_LEGACY_SERIAL_PORTS+1];
-static unsigned int old_serial_count;
-
-void __init generic_find_legacy_serial_ports(u64 *physport,
-		unsigned int *default_speed)
-{
-	struct device_node *np;
-	u32 *sizeprop;
-
-	struct isa_reg_property {
-		u32 space;
-		u32 address;
-		u32 size;
-	};
-	struct pci_reg_property {
-		struct pci_address addr;
-		u32 size_hi;
-		u32 size_lo;
-	};                                                                        
-
-	DBG(" -> generic_find_legacy_serial_port()\n");
-
-	*physport = 0;
-	if (default_speed)
-		*default_speed = 0;
-
-	np = of_find_node_by_path("/");
-	if (!np)
-		return;
-
-	/* First fill our array */
-	for (np = NULL; (np = of_find_node_by_type(np, "serial"));) {
-		struct device_node *isa, *pci;
-		struct isa_reg_property *reg;
-		unsigned long phys_size, addr_size, io_base;
-		u32 *rangesp;
-		u32 *interrupts, *clk, *spd;
-		char *typep;
-		int index, rlen, rentsize;
-
-		/* Ok, first check if it's under an "isa" parent */
-		isa = of_get_parent(np);
-		if (!isa || strcmp(isa->name, "isa")) {
-			DBG("%s: no isa parent found\n", np->full_name);
-			continue;
-		}
-		
-		/* Now look for an "ibm,aix-loc" property that gives us ordering
-		 * if any...
-		 */
-	 	typep = (char *)get_property(np, "ibm,aix-loc", NULL);
-
-		/* Get the ISA port number */
-		reg = (struct isa_reg_property *)get_property(np, "reg", NULL);	
-		if (reg == NULL)
-			goto next_port;
-		/* We assume the interrupt number isn't translated ... */
-		interrupts = (u32 *)get_property(np, "interrupts", NULL);
-		/* get clock freq. if present */
-		clk = (u32 *)get_property(np, "clock-frequency", NULL);
-		/* get default speed if present */
-		spd = (u32 *)get_property(np, "current-speed", NULL);
-		/* Default to locate at end of array */
-		index = old_serial_count; /* end of the array by default */
-
-		/* If we have a location index, then use it */
-		if (typep && *typep == 'S') {
-			index = simple_strtol(typep+1, NULL, 0) - 1;
-			/* if index is out of range, use end of array instead */
-			if (index >= MAX_LEGACY_SERIAL_PORTS)
-				index = old_serial_count;
-			/* if our index is still out of range, that mean that
-			 * array is full, we could scan for a free slot but that
-			 * make little sense to bother, just skip the port
-			 */
-			if (index >= MAX_LEGACY_SERIAL_PORTS)
-				goto next_port;
-			if (index >= old_serial_count)
-				old_serial_count = index + 1;
-			/* Check if there is a port who already claimed our slot */
-			if (serial_ports[index].iobase != 0) {
-				/* if we still have some room, move it, else override */
-				if (old_serial_count < MAX_LEGACY_SERIAL_PORTS) {
-					DBG("Moved legacy port %d -> %d\n", index,
-					    old_serial_count);
-					serial_ports[old_serial_count++] =
-						serial_ports[index];
-				} else {
-					DBG("Replacing legacy port %d\n", index);
-				}
-			}
-		}
-		if (index >= MAX_LEGACY_SERIAL_PORTS)
-			goto next_port;
-		if (index >= old_serial_count)
-			old_serial_count = index + 1;
-
-		/* Now fill the entry */
-		memset(&serial_ports[index], 0, sizeof(struct plat_serial8250_port));
-		serial_ports[index].uartclk = clk ? *clk : BASE_BAUD * 16;
-		serial_ports[index].iobase = reg->address;
-		serial_ports[index].irq = interrupts ? interrupts[0] : 0;
-		serial_ports[index].flags = ASYNC_BOOT_AUTOCONF;
-
-		DBG("Added legacy port, index: %d, port: %x, irq: %d, clk: %d\n",
-		    index,
-		    serial_ports[index].iobase,
-		    serial_ports[index].irq,
-		    serial_ports[index].uartclk);
-
-		/* Get phys address of IO reg for port 1 */
-		if (index != 0)
-			goto next_port;
-
-		pci = of_get_parent(isa);
-		if (!pci) {
-			DBG("%s: no pci parent found\n", np->full_name);
-			goto next_port;
-		}
-
-		rangesp = (u32 *)get_property(pci, "ranges", &rlen);
-		if (rangesp == NULL) {
-			of_node_put(pci);
-			goto next_port;
-		}
-		rlen /= 4;
-
-		/* we need the #size-cells of the PCI bridge node itself */
-		phys_size = 1;
-		sizeprop = (u32 *)get_property(pci, "#size-cells", NULL);
-		if (sizeprop != NULL)
-			phys_size = *sizeprop;
-		/* we need the parent #addr-cells */
-		addr_size = prom_n_addr_cells(pci);
-		rentsize = 3 + addr_size + phys_size;
-		io_base = 0;
-		for (;rlen >= rentsize; rlen -= rentsize,rangesp += rentsize) {
-			if (((rangesp[0] >> 24) & 0x3) != 1)
-				continue; /* not IO space */
-			io_base = rangesp[3];
-			if (addr_size == 2)
-				io_base = (io_base << 32) | rangesp[4];
-		}
-		if (io_base != 0) {
-			*physport = io_base + reg->address;
-			if (default_speed && spd)
-				*default_speed = *spd;
-		}
-		of_node_put(pci);
-	next_port:
-		of_node_put(isa);
-	}
-
-	DBG(" <- generic_find_legacy_serial_port()\n");
-}
-
-static struct platform_device serial_device = {
-	.name	= "serial8250",
-	.id	= PLAT8250_DEV_PLATFORM,
-	.dev	= {
-		.platform_data = serial_ports,
-	},
-};
-
-static int __init serial_dev_init(void)
-{
-	return platform_device_register(&serial_device);
-}
-arch_initcall(serial_dev_init);
-
-#endif /* CONFIG_PPC_ISERIES */
-
 int check_legacy_ioport(unsigned long base_port)
 {
 	if (ppc_md.check_legacy_ioport == NULL)

arch/powerpc/kernel/udbg.c

@@ -99,7 +99,7 @@ static void udbg_console_write(struct console *con, const char *s,
 static struct console udbg_console = {
 	.name	= "udbg",
 	.write	= udbg_console_write,
-	.flags	= CON_PRINTBUFFER,
+	.flags	= CON_PRINTBUFFER | CON_ENABLED,
 	.index	= -1,
 };
 

arch/powerpc/kernel/udbg_16550.c

@@ -43,6 +43,8 @@ struct NS16550 {
 #define LSR_TEMT 0x40  /* Xmitter empty */
 #define LSR_ERR  0x80  /* Error */
 
+#define LCR_DLAB 0x80
+
 static volatile struct NS16550 __iomem *udbg_comport;
 
 static void udbg_550_putc(unsigned char c)
@@ -77,29 +79,70 @@ static unsigned char udbg_550_getc(void)
 	return 0;
 }
 
-void udbg_init_uart(void __iomem *comport, unsigned int speed)
+void udbg_init_uart(void __iomem *comport, unsigned int speed,
+		    unsigned int clock)
 {
-	u16 dll = speed ? (115200 / speed) : 12;
+	unsigned int dll, base_bauds = clock / 16;
+
+	if (speed == 0)
+		speed = 9600;
+	dll = base_bauds / speed;
 
 	if (comport) {
 		udbg_comport = (struct NS16550 __iomem *)comport;
 		out_8(&udbg_comport->lcr, 0x00);
 		out_8(&udbg_comport->ier, 0xff);
 		out_8(&udbg_comport->ier, 0x00);
-		out_8(&udbg_comport->lcr, 0x80);	/* Access baud rate */
-		out_8(&udbg_comport->dll, dll & 0xff);	/* 1 = 115200,  2 = 57600,
-							   3 = 38400, 12 = 9600 baud */
-		out_8(&udbg_comport->dlm, dll >> 8);	/* dll >> 8 which should be zero
-							   for fast rates; */
-		out_8(&udbg_comport->lcr, 0x03);	/* 8 data, 1 stop, no parity */
-		out_8(&udbg_comport->mcr, 0x03);	/* RTS/DTR */
-		out_8(&udbg_comport->fcr ,0x07);	/* Clear & enable FIFOs */
+		out_8(&udbg_comport->lcr, LCR_DLAB);
+		out_8(&udbg_comport->dll, dll & 0xff);
+		out_8(&udbg_comport->dlm, dll >> 8);
+		/* 8 data, 1 stop, no parity */
+		out_8(&udbg_comport->lcr, 0x03);
+		/* RTS/DTR */
+		out_8(&udbg_comport->mcr, 0x03);
+		/* Clear & enable FIFOs */
+		out_8(&udbg_comport->fcr ,0x07);
 		udbg_putc = udbg_550_putc;
 		udbg_getc = udbg_550_getc;
 		udbg_getc_poll = udbg_550_getc_poll;
 	}
 }
 
+unsigned int udbg_probe_uart_speed(void __iomem *comport, unsigned int clock)
+{
+	unsigned int dll, dlm, divisor, prescaler, speed;
+	u8 old_lcr;
+	volatile struct NS16550 __iomem *port = comport;
+
+	old_lcr = in_8(&port->lcr);
+
+	/* select divisor latch registers.  */
+	out_8(&port->lcr, LCR_DLAB);
+
+	/* now, read the divisor */
+	dll = in_8(&port->dll);
+	dlm = in_8(&port->dlm);
+	divisor = dlm << 8 | dll;
+
+	/* check prescaling */
+	if (in_8(&port->mcr) & 0x80)
+		prescaler = 4;
+	else
+		prescaler = 1;
+
+	/* restore the LCR */
+	out_8(&port->lcr, old_lcr);
+
+	/* calculate speed */
+	speed = (clock / prescaler) / (divisor * 16);
+
+	/* sanity check */
+	if (speed < 9600 || speed > 115200)
+		speed = 9600;
+
+	return speed;
+}
+
 #ifdef CONFIG_PPC_MAPLE
 void udbg_maple_real_putc(unsigned char c)
 {

arch/powerpc/platforms/maple/setup.c

@@ -192,20 +192,6 @@ static void __init maple_init_early(void)
 	 */
 	hpte_init_native();
 
-	/* Find the serial port */
-	generic_find_legacy_serial_ports(&physport, &default_speed);
-
-	DBG("phys port addr: %lx\n", (long)physport);
-
-	if (physport) {
-		void *comport;
-		/* Map the uart for udbg. */
-		comport = (void *)ioremap(physport, 16);
-		udbg_init_uart(comport, default_speed);
-
-		DBG("Hello World !\n");
-	}
-
 	/* Setup interrupt mapping options */
 	ppc64_interrupt_controller = IC_OPEN_PIC;
 

arch/powerpc/platforms/pseries/lpar.c

@@ -24,6 +24,7 @@
 #include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/dma-mapping.h>
+#include <linux/console.h>
 #include <asm/processor.h>
 #include <asm/mmu.h>
 #include <asm/page.h>
@@ -191,7 +192,7 @@ static unsigned char udbg_getcLP(void)
 /* call this from early_init() for a working debug console on
  * vterm capable LPAR machines
  */
-void udbg_init_debug_lpar(void)
+void __init udbg_init_debug_lpar(void)
 {
 	vtermno = 0;
 	udbg_putc = udbg_putcLP;
@@ -200,63 +201,54 @@ void udbg_init_debug_lpar(void)
 }
 
 /* returns 0 if couldn't find or use /chosen/stdout as console */
-int find_udbg_vterm(void)
+void __init find_udbg_vterm(void)
 {
 	struct device_node *stdout_node;
 	u32 *termno;
 	char *name;
-	int found = 0;
+	int add_console;
 
 	/* find the boot console from /chosen/stdout */
 	if (!of_chosen)
-		return 0;
+		return;
 	name = (char *)get_property(of_chosen, "linux,stdout-path", NULL);
 	if (name == NULL)
-		return 0;
+		return;
 	stdout_node = of_find_node_by_path(name);
 	if (!stdout_node)
-		return 0;
-
-	/* now we have the stdout node; figure out what type of device it is. */
+		return;
 	name = (char *)get_property(stdout_node, "name", NULL);
 	if (!name) {
 		printk(KERN_WARNING "stdout node missing 'name' property!\n");
 		goto out;
 	}
+	/* The user has requested a console so this is already set up. */
+	add_console = !strstr(cmd_line, "console=");
 
-	if (strncmp(name, "vty", 3) == 0) {
-		if (device_is_compatible(stdout_node, "hvterm1")) {
-			termno = (u32 *)get_property(stdout_node, "reg", NULL);
-			if (termno) {
-				vtermno = termno[0];
-				udbg_putc = udbg_putcLP;
-				udbg_getc = udbg_getcLP;
-				udbg_getc_poll = udbg_getc_pollLP;
-				found = 1;
-			}
-		} else if (device_is_compatible(stdout_node, "hvterm-protocol")) {
-			termno = (u32 *)get_property(stdout_node, "reg", NULL);
-			if (termno) {
-				vtermno = termno[0];
-				udbg_putc = udbg_hvsi_putc;
-				udbg_getc = udbg_hvsi_getc;
-				udbg_getc_poll = udbg_hvsi_getc_poll;
-				found = 1;
-			}
-		}
-	} else if (strncmp(name, "serial", 6)) {
-		/* XXX fix ISA serial console */
-		printk(KERN_WARNING "serial stdout on LPAR ('%s')! "
-				"can't print udbg messages\n",
-		       stdout_node->full_name);
-	} else {
-		printk(KERN_WARNING "don't know how to print to stdout '%s'\n",
-		       stdout_node->full_name);
+	/* Check if it's a virtual terminal */
+	if (strncmp(name, "vty", 3) != 0)
+		goto out;
+	termno = (u32 *)get_property(stdout_node, "reg", NULL);
+	if (termno == NULL)
+		goto out;
+	vtermno = termno[0];
+
+	if (device_is_compatible(stdout_node, "hvterm1")) {
+		udbg_putc = udbg_putcLP;
+		udbg_getc = udbg_getcLP;
+		udbg_getc_poll = udbg_getc_pollLP;
+		if (add_console)
+			add_preferred_console("hvc", termno[0] & 0xff, NULL);
+	} else if (device_is_compatible(stdout_node, "hvterm-protocol")) {
+		vtermno = termno[0];
+		udbg_putc = udbg_hvsi_putc;
+		udbg_getc = udbg_hvsi_getc;
+		udbg_getc_poll = udbg_hvsi_getc_poll;
+		if (add_console)
+			add_preferred_console("hvsi", termno[0] & 0xff, NULL);
 	}
-
 out:
 	of_node_put(stdout_node);
-	return found;
 }
 
 void vpa_init(int cpu)

arch/powerpc/platforms/pseries/setup.c

@@ -79,8 +79,6 @@
 extern void find_udbg_vterm(void);
 extern void system_reset_fwnmi(void);	/* from head.S */
 extern void machine_check_fwnmi(void);	/* from head.S */
-extern void generic_find_legacy_serial_ports(u64 *physport,
-		unsigned int *default_speed);
 
 int fwnmi_active;  /* TRUE if an FWNMI handler is present */
 
@@ -366,10 +364,7 @@ static int pseries_set_xdabr(unsigned long dabr)
  */
 static void __init pSeries_init_early(void)
 {
-	void *comport;
 	int iommu_off = 0;
-	unsigned int default_speed;
-	u64 physport;
 
 	DBG(" -> pSeries_init_early()\n");
 
@@ -383,17 +378,8 @@ static void __init pSeries_init_early(void)
 			     get_property(of_chosen, "linux,iommu-off", NULL));
 	}
 
-	generic_find_legacy_serial_ports(&physport, &default_speed);
-
 	if (platform_is_lpar())
 		find_udbg_vterm();
-	else if (physport) {
-		/* Map the uart for udbg. */
-		comport = (void *)ioremap(physport, 16);
-		udbg_init_uart(comport, default_speed);
-
-		DBG("Hello World !\n");
-	}
 
 	if (firmware_has_feature(FW_FEATURE_DABR))
 		ppc_md.set_dabr = pseries_set_dabr;

arch/ppc/kernel/pci.c

@@ -815,8 +815,7 @@ EXPORT_SYMBOL(pci_device_to_OF_node);
  * to set pci_assign_all_buses to 1 and still use RTAS for PCI
  * config cycles.
  */
-struct pci_controller*
-pci_find_hose_for_OF_device(struct device_node* node)
+struct pci_controller* pci_find_hose_for_OF_device(struct device_node* node)
 {
 	if (!have_of)
 		return NULL;

include/asm-powerpc/pci-bridge.h

@@ -140,6 +140,9 @@ static inline struct pci_controller *pci_bus_to_host(struct pci_bus *bus)
 	return PCI_DN(busdn)->phb;
 }
 
+extern struct pci_controller*
+pci_find_hose_for_OF_device(struct device_node* node);
+
 extern struct pci_controller *
 pcibios_alloc_controller(struct device_node *dev);
 extern void pcibios_free_controller(struct pci_controller *phb);

include/asm-powerpc/serial.h

@@ -15,4 +15,6 @@
 /* Default baud base if not found in device-tree */
 #define BASE_BAUD ( 1843200 / 16 )
 
+extern void find_legacy_serial_ports(void);
+
 #endif /* _PPC64_SERIAL_H */

include/asm-powerpc/udbg.h

@@ -24,7 +24,10 @@ extern int udbg_read(char *buf, int buflen);
 extern void register_early_udbg_console(void);
 extern void udbg_printf(const char *fmt, ...);
 
-extern void udbg_init_uart(void __iomem *comport, unsigned int speed);
+extern void udbg_init_uart(void __iomem *comport, unsigned int speed,
+			   unsigned int clock);
+extern unsigned int udbg_probe_uart_speed(void __iomem *comport,
+					  unsigned int clock);
 
 struct device_node;
 extern void udbg_init_scc(struct device_node *np);