legacy_serial.c

来自「LINUX 2.6.17.4的源码」· C语言 代码 · 共 554 行 · 第 1/2 页

			DBG("stdout is %s\n", stdout->full_name);
	} else {
		DBG(" no linux,stdout-path !\n");
	}

	/* First fill our array with SOC ports */
	for (np = NULL; (np = of_find_compatible_node(np, "serial", "ns16550")) != NULL;) {
		struct device_node *soc = of_get_parent(np);
		if (soc && !strcmp(soc->type, "soc")) {
			index = add_legacy_soc_port(np, np);
			if (index >= 0 && np == stdout)
				legacy_serial_console = index;
		}
		of_node_put(soc);
	}

	/* First fill our array with ISA ports */
	for (np = NULL; (np = of_find_node_by_type(np, "serial"));) {
		struct device_node *isa = of_get_parent(np);
		if (isa && !strcmp(isa->name, "isa")) {
			index = add_legacy_isa_port(np, isa);
			if (index >= 0 && np == stdout)
				legacy_serial_console = index;
		}
		of_node_put(isa);
	}

#ifdef CONFIG_PCI
	/* Next, try to locate PCI ports */
	for (np = NULL; (np = of_find_all_nodes(np));) {
		struct device_node *pci, *parent = of_get_parent(np);
		if (parent && !strcmp(parent->name, "isa")) {
			of_node_put(parent);
			continue;
		}
		if (strcmp(np->name, "serial") && strcmp(np->type, "serial")) {
			of_node_put(parent);
			continue;
		}
		/* Check for known pciclass, and also check wether we have
		 * a device with child nodes for ports or not
		 */
		if (device_is_compatible(np, "pciclass,0700") ||
		    device_is_compatible(np, "pciclass,070002"))
			pci = np;
		else if (device_is_compatible(parent, "pciclass,0700") ||
			 device_is_compatible(parent, "pciclass,070002"))
			pci = parent;
		else {
			of_node_put(parent);
			continue;
		}
		index = add_legacy_pci_port(np, pci);
		if (index >= 0 && np == stdout)
			legacy_serial_console = index;
		of_node_put(parent);
	}
#endif

	DBG("legacy_serial_console = %d\n", legacy_serial_console);
	if (legacy_serial_console >= 0)
		setup_legacy_serial_console(legacy_serial_console);
	DBG(" <- find_legacy_serial_port()\n");
}

static struct platform_device serial_device = {
	.name	= "serial8250",
	.id	= PLAT8250_DEV_PLATFORM,
	.dev	= {
		.platform_data = legacy_serial_ports,
	},
};

static void __init fixup_port_irq(int index,
				  struct device_node *np,
				  struct plat_serial8250_port *port)
{
	DBG("fixup_port_irq(%d)\n", index);

	/* Check for interrupts in that node */
	if (np->n_intrs > 0) {
		port->irq = np->intrs[0].line;
		DBG(" port %d (%s), irq=%d\n",
		    index, np->full_name, port->irq);
		return;
	}

	/* Check for interrupts in the parent */
	np = of_get_parent(np);
	if (np == NULL)
		return;

	if (np->n_intrs > 0) {
		port->irq = np->intrs[0].line;
		DBG(" port %d (%s), irq=%d\n",
		    index, np->full_name, port->irq);
	}
	of_node_put(np);
}

static void __init fixup_port_pio(int index,
				  struct device_node *np,
				  struct plat_serial8250_port *port)
{
#ifdef CONFIG_PCI
	struct pci_controller *hose;

	DBG("fixup_port_pio(%d)\n", index);

	hose = pci_find_hose_for_OF_device(np);
	if (hose) {
		unsigned long offset = (unsigned long)hose->io_base_virt -
#ifdef CONFIG_PPC64
			pci_io_base;
#else
			isa_io_base;
#endif
		DBG("port %d, IO %lx -> %lx\n",
		    index, port->iobase, port->iobase + offset);
		port->iobase += offset;
	}
#endif
}

static void __init fixup_port_mmio(int index,
				   struct device_node *np,
				   struct plat_serial8250_port *port)
{
	DBG("fixup_port_mmio(%d)\n", index);

	port->membase = ioremap(port->mapbase, 0x100);
}

/*
 * This is called as an arch initcall, hopefully before the PCI bus is
 * probed and/or the 8250 driver loaded since we need to register our
 * platform devices before 8250 PCI ones are detected as some of them
 * must properly "override" the platform ones.
 *
 * This function fixes up the interrupt value for platform ports as it
 * couldn't be done earlier before interrupt maps have been parsed. It
 * also "corrects" the IO address for PIO ports for the same reason,
 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then
 * registers all those platform ports for use by the 8250 driver when it
 * finally loads.
 */
static int __init serial_dev_init(void)
{
	int i;

	if (legacy_serial_count == 0)
		return -ENODEV;

	/*
	 * Before we register the platfrom serial devices, we need
	 * to fixup their interrutps and their IO ports.
	 */
	DBG("Fixing serial ports interrupts and IO ports ...\n");

	for (i = 0; i < legacy_serial_count; i++) {
		struct plat_serial8250_port *port = &legacy_serial_ports[i];
		struct device_node *np = legacy_serial_infos[i].np;

		if (port->irq == NO_IRQ)
			fixup_port_irq(i, np, port);
		if (port->iotype == UPIO_PORT)
			fixup_port_pio(i, np, port);
		if (port->iotype == UPIO_MEM)
			fixup_port_mmio(i, np, port);
	}

	DBG("Registering platform serial ports\n");

	return platform_device_register(&serial_device);
}
arch_initcall(serial_dev_init);


/*
 * This is called very early, as part of console_init() (typically just after
 * time_init()). This function is respondible for trying to find a good
 * default console on serial ports. It tries to match the open firmware
 * default output with one of the available serial console drivers, either
 * one of the platform serial ports that have been probed earlier by
 * find_legacy_serial_ports() or some more platform specific ones.
 */
static int __init check_legacy_serial_console(void)
{
	struct device_node *prom_stdout = NULL;
	int speed = 0, offset = 0;
	char *name;
	u32 *spd;

	DBG(" -> check_legacy_serial_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;
	}

	if (legacy_serial_console < 0) {
		DBG(" legacy_serial_console not found !\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 (spd)
		speed = *spd;

	if (0)
		;
#ifdef CONFIG_SERIAL_8250_CONSOLE
	else if (strcmp(name, "serial") == 0) {
		int i;
		/* Look for it in probed array */
		for (i = 0; i < legacy_serial_count; i++) {
			if (prom_stdout != legacy_serial_infos[i].np)
				continue;
			offset = i;
			speed = legacy_serial_infos[i].speed;
			break;
		}
		if (i >= legacy_serial_count)
			goto not_found;
	}
#endif /* CONFIG_SERIAL_8250_CONSOLE */
#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 (speed) {
		static char __initdata opt[16];
		sprintf(opt, "%d", speed);
		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(check_legacy_serial_console);