[PATCH] m68k: HP300 8250 serial for DCA and APCI ports

Created HP300 8250 driver which supports DCA and APCI ports. Support for APCI
is still experimental and unfinished (no support for interrupts).
Console support should be okay though (from Kars de Jong)
Signed-off-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/serial/8250_hp300.c

+/*
+ * Driver for the 98626/98644/internal serial interface on hp300/hp400
+ * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
+ *
+ * Ported from 2.2 and modified to use the normal 8250 driver
+ * by Kars de Jong <jongk@linux-m68k.org>, May 2004.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/tty.h>
+#include <linux/serial.h>
+#include <linux/serialP.h>
+#include <linux/serial_core.h>
+#include <linux/delay.h>
+#include <linux/dio.h>
+#include <linux/console.h>
+#include <asm/io.h>
+
+#if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI)
+#warning CONFIG_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
+#endif
+
+struct hp300_port
+{
+	struct hp300_port *next;	/* next port */
+	unsigned long dio_base;		/* start of DIO registers */
+	int scode;                      /* select code of this board */
+	int line;			/* line (tty) number */
+};
+
+extern int hp300_uart_scode;
+
+static struct hp300_port *hp300_ports;
+
+/* Offset to UART registers from base of DCA */
+#define UART_OFFSET	17
+
+#define DCA_ID		0x01	/* ID (read), reset (write) */
+#define DCA_IC		0x03	/* Interrupt control        */
+
+/* Interrupt control */
+#define DCA_IC_IE	0x80	/* Master interrupt enable  */
+
+#define HPDCA_BAUD_BASE 153600
+
+/* Base address of the Frodo part */
+#define FRODO_BASE	(0x41c000)
+
+/*
+ * Where we find the 8250-like APCI ports, and how far apart they are.
+ */
+#define FRODO_APCIBASE		0x0
+#define FRODO_APCISPACE		0x20
+#define FRODO_APCI_OFFSET(x)	(FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
+
+#define HPAPCI_BAUD_BASE 500400
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+/*
+ * Parse the bootinfo to find descriptions for headless console and 
+ * debug serial ports and register them with the 8250 driver.
+ * This function should be called before serial_console_init() is called
+ * to make sure the serial console will be available for use. IA-64 kernel
+ * calls this function from setup_arch() after the EFI and ACPI tables have
+ * been parsed.
+ */
+int __init hp300_setup_serial_console(void)
+{
+	int scode;
+	struct uart_port port;
+
+	memset(&port, 0, sizeof(port));
+
+	if (hp300_uart_scode < 0 || hp300_uart_scode > 256)
+		return 0;
+
+	scode = hp300_uart_scode;
+
+	/* Memory mapped I/O */
+	port.iotype = UPIO_MEM;
+	port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
+	port.type = PORT_UNKNOWN;
+
+	/* Check for APCI console */
+	if (scode == 256)
+	{
+#ifdef CONFIG_HPAPCI
+		printk(KERN_INFO "Serial console is HP APCI 1\n");
+
+		port.uartclk = HPAPCI_BAUD_BASE * 16;
+		port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
+		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
+		port.regshift = 2;
+		add_preferred_console("ttyS", port.line, "9600n8");
+#else
+		printk(KERN_WARNING "Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
+		return 0;
+#endif
+	}
+	else
+	{
+#ifdef CONFIG_HPDCA
+		unsigned long pa = dio_scodetophysaddr(scode);
+		if (!pa) {
+			return 0;
+		}
+
+		printk(KERN_INFO "Serial console is HP DCA at select code %d\n", scode);
+
+		port.uartclk = HPDCA_BAUD_BASE * 16;
+		port.mapbase = (pa + UART_OFFSET);
+		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
+		port.regshift = 1;
+		port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
+
+		/* Enable board-interrupts */
+		out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
+
+		if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80) {
+			add_preferred_console("ttyS", port.line, "9600n8");
+		}
+#else
+		printk(KERN_WARNING "Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
+		return 0;
+#endif
+	}
+
+	if (early_serial_setup(&port) < 0) {
+		printk(KERN_WARNING "hp300_setup_serial_console(): early_serial_setup() failed.\n");
+	}
+
+	return 0;
+}
+#endif /* CONFIG_SERIAL_8250_CONSOLE */
+
+static int __init hp300_8250_init(void)
+{
+	static int called = 0;
+#ifdef CONFIG_HPDCA
+	int scode;
+#endif
+	int line, num_ports;
+	unsigned long base;
+	struct serial_struct serial_req;
+	struct hp300_port *port;
+
+	if (called)
+		return -ENODEV;
+	called = 1;
+	num_ports = 0;
+
+	if (!MACH_IS_HP300) {
+		return -ENODEV;
+	}
+
+#ifdef CONFIG_HPDCA
+	while (1) {
+                /* We detect boards by looking for DIO boards which match a
+                 * given subset of IDs. dio_find() returns the board's scancode.
+                 * The scancode to physaddr mapping is a property of the hardware,
+                 * as is the scancode to IPL (interrupt priority) mapping.
+                 */
+                scode = dio_find(DIO_ID_DCA0);
+                if (scode < 0)
+			scode = dio_find(DIO_ID_DCA0REM);
+                if (scode < 0)
+			scode = dio_find(DIO_ID_DCA1);
+                if (scode < 0)
+			scode = dio_find(DIO_ID_DCA1REM);
+                if (scode < 0)
+			break;		/* no, none at all */
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+		if (hp300_uart_scode == scode) {
+			/* Already got it */
+			dio_config_board(scode);
+			continue;
+		}
+#endif
+
+		/* Create new serial device */
+		port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
+		if (!port)
+			return -ENOMEM;
+
+		memset(&serial_req, 0, sizeof(struct serial_struct));
+		
+		base = dio_scodetophysaddr(scode);
+
+                /* If we want to tell the DIO code that this board is configured,
+                 * we should do that here.
+                 */
+                dio_config_board(scode);
+
+		/* Memory mapped I/O */
+		serial_req.io_type = SERIAL_IO_MEM;
+		serial_req.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
+		serial_req.irq = dio_scodetoipl(scode);
+		serial_req.baud_base = HPDCA_BAUD_BASE;
+		serial_req.iomap_base = (base + UART_OFFSET);
+		serial_req.iomem_base = (char *)(serial_req.iomap_base + DIO_VIRADDRBASE);
+		serial_req.iomem_reg_shift = 1;
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+		if (hp300_uart_scode != scode) {
+#endif
+                /* Reset the DCA */
+                out_8(base + DIO_VIRADDRBASE + DCA_ID, 0xff);
+                udelay(100);
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+		}
+#endif
+
+		line = register_serial(&serial_req);
+
+		if (line < 0) {
+			printk(KERN_NOTICE "8250_hp300: register_serial() DCA scode %d"
+			       " irq %d failed\n", scode, serial_req.irq);
+			kfree(port);
+			continue;
+		}
+
+		/* Enable board-interrupts */
+		out_8(base + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
+
+		port->dio_base = base + DIO_VIRADDRBASE;
+		port->scode = scode;
+		port->line = line;
+		port->next = hp300_ports;
+		hp300_ports = port;
+
+		num_ports++;
+        }
+#endif
+
+#ifdef CONFIG_HPAPCI
+	if (hp300_model >= HP_400)
+	{
+		int i;
+
+		/* These models have the Frodo chip.
+		 * Port 0 is reserved for the Apollo Domain keyboard.
+		 * Port 1 is either the console or the DCA.
+		 */
+		for (i = 1; i < 4; i++) {
+			/* Port 1 is the console on a 425e, on other machines it's mapped to
+			 * DCA.
+			 */
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+			if (i == 1) {
+				continue;
+			}
+#endif
+
+			/* Create new serial device */
+			port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
+			if (!port)
+				return -ENOMEM;
+
+			memset(&serial_req, 0, sizeof(struct serial_struct));
+
+			base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
+
+			/* Memory mapped I/O */
+			serial_req.io_type = SERIAL_IO_MEM;
+			serial_req.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
+			/* XXX - no interrupt support yet */
+			serial_req.irq = 0;
+			serial_req.baud_base = HPAPCI_BAUD_BASE;
+			serial_req.iomap_base = base;
+			serial_req.iomem_base = (char *)(serial_req.iomap_base + DIO_VIRADDRBASE);
+			serial_req.iomem_reg_shift = 2;
+
+			line = register_serial(&serial_req);
+
+			if (line < 0) {
+				printk(KERN_NOTICE "8250_hp300: register_serial() APCI %d"
+				       " irq %d failed\n", i, serial_req.irq);
+				kfree(port);
+				continue;
+			}
+
+			port->dio_base = 0;
+			port->line = line;
+			port->next = hp300_ports;
+			hp300_ports = port;
+
+			num_ports++;
+		}
+	}
+#endif
+
+	/* Any boards found? */
+	if (!num_ports)
+		return -ENODEV;
+
+	return 0;
+}
+
+static void __exit hp300_8250_exit(void)
+{
+	struct hp300_port *port, *to_free;
+
+	for (port = hp300_ports; port; ) {
+		unregister_serial(port->line);
+
+#ifdef CONFIG_HPDCA
+		if (port->dio_base) {
+			/* Disable board-interrupts */
+			out_8(port->dio_base + DCA_IC, 0);
+
+			dio_unconfig_board(port->scode);
+		}
+#endif
+
+		to_free = port;
+		port = port->next;
+		kfree(to_free);
+	}
+
+	hp300_ports = NULL;
+}
+
+module_init(hp300_8250_init);
+module_exit(hp300_8250_exit);
+MODULE_DESCRIPTION("HP DCA/APCI serial driver");
+MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
+MODULE_LICENSE("GPL");

drivers/serial/Makefile

@@ -9,6 +9,7 @@ serial-8250-$(CONFIG_SERIAL_8250_ACPI) += 8250_acpi.o
 serial-8250-$(CONFIG_GSC) += 8250_gsc.o
 serial-8250-$(CONFIG_PCI) += 8250_pci.o
 serial-8250-$(CONFIG_PNP) += 8250_pnp.o
+serial-8250-$(CONFIG_HP300) += 8250_hp300.o
 
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o