[SPARC64]: Add SUN4V Hypervisor Console driver.
David S. Miller [Sat, 11 Feb 2006 10:25:21 +0000 (02:25 -0800)]
Since it can do things like BREAK and HUP, we implement
this as a serial uart driver.

This still needs interrupt probing code, as I haven't figured
out how interrupts will work or be probed for on SUN4V yet.

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

drivers/serial/Kconfig
drivers/serial/Makefile
drivers/serial/sunhv.c [new file with mode: 0644]
include/linux/serial_core.h

index b3c561a..89e5413 100644 (file)
@@ -582,6 +582,13 @@ config SERIAL_SUNSAB_CONSOLE
          on your Sparc system as the console, you can do so by answering
          Y to this option.
 
+config SERIAL_SUNHV
+       bool "Sun4v Hypervisor Console support"
+       depends on SPARC64
+       help
+         This driver supports the console device found on SUN4V Sparc
+         systems.  Say Y if you want to be able to use this device.
+
 config SERIAL_IP22_ZILOG
        tristate "IP22 Zilog8530 serial support"
        depends on SGI_IP22
index eaf8e01..0f7f8d7 100644 (file)
@@ -34,6 +34,7 @@ obj-$(CONFIG_SERIAL_SUNZILOG) += sunzilog.o
 obj-$(CONFIG_SERIAL_IP22_ZILOG) += ip22zilog.o
 obj-$(CONFIG_SERIAL_SUNSU) += sunsu.o
 obj-$(CONFIG_SERIAL_SUNSAB) += sunsab.o
+obj-$(CONFIG_SERIAL_SUNHV) += sunhv.o
 obj-$(CONFIG_SERIAL_MUX) += mux.o
 obj-$(CONFIG_SERIAL_68328) += 68328serial.o
 obj-$(CONFIG_SERIAL_68360) += 68360serial.o
diff --git a/drivers/serial/sunhv.c b/drivers/serial/sunhv.c
new file mode 100644 (file)
index 0000000..2ba716e
--- /dev/null
@@ -0,0 +1,481 @@
+/* sunhv.c: Serial driver for SUN4V hypervisor console.
+ *
+ * Copyright (C) 2006 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/major.h>
+#include <linux/circ_buf.h>
+#include <linux/serial.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+
+#include <asm/hypervisor.h>
+#include <asm/spitfire.h>
+
+#if defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+#include "suncore.h"
+
+#define CON_BREAK      ((long)-1)
+#define CON_HUP                ((long)-2)
+
+static inline long hypervisor_con_getchar(long *status)
+{
+       register unsigned long func asm("%o5");
+       register unsigned long arg0 asm("%o0");
+       register unsigned long arg1 asm("%o1");
+
+       func = HV_FAST_CONS_GETCHAR;
+       arg0 = 0;
+       arg1 = 0;
+       __asm__ __volatile__("ta        %6"
+                            : "=&r" (func), "=&r" (arg0), "=&r" (arg1)
+                            : "0" (func), "1" (arg0), "2" (arg1),
+                              "i" (HV_FAST_TRAP));
+
+       *status = arg0;
+
+       return (long) arg1;
+}
+
+static inline long hypervisor_con_putchar(long ch)
+{
+       register unsigned long func asm("%o5");
+       register unsigned long arg0 asm("%o0");
+
+       func = HV_FAST_CONS_PUTCHAR;
+       arg0 = ch;
+       __asm__ __volatile__("ta        %4"
+                            : "=&r" (func), "=&r" (arg0)
+                            : "0" (func), "1" (arg0), "i" (HV_FAST_TRAP));
+
+       return (long) arg0;
+}
+
+#define IGNORE_BREAK   0x1
+#define IGNORE_ALL     0x2
+
+static int hung_up = 0;
+
+static struct tty_struct *receive_chars(struct uart_port *port, struct pt_regs *regs)
+{
+       struct tty_struct *tty = NULL;
+       int saw_console_brk = 0;
+       int limit = 10000;
+
+       if (port->info != NULL)         /* Unopened serial console */
+               tty = port->info->tty;
+
+       while (limit-- > 0) {
+               long status;
+               long c = hypervisor_con_getchar(&status);
+               unsigned char flag;
+
+               if (status == HV_EWOULDBLOCK)
+                       break;
+
+               if (c == CON_BREAK) {
+                       saw_console_brk = 1;
+                       c = 0;
+               }
+
+               if (c == CON_HUP) {
+                       hung_up = 1;
+                       uart_handle_dcd_change(port, 0);
+               } else if (hung_up) {
+                       hung_up = 0;
+                       uart_handle_dcd_change(port, 1);
+               }
+
+               if (tty == NULL) {
+                       uart_handle_sysrq_char(port, c, regs);
+                       continue;
+               }
+
+               flag = TTY_NORMAL;
+               port->icount.rx++;
+               if (c == CON_BREAK) {
+                       port->icount.brk++;
+                       if (uart_handle_break(port))
+                               continue;
+                       flag = TTY_BREAK;
+               }
+
+               if (uart_handle_sysrq_char(port, c, regs))
+                       continue;
+
+               if ((port->ignore_status_mask & IGNORE_ALL) ||
+                   ((port->ignore_status_mask & IGNORE_BREAK) &&
+                    (c == CON_BREAK)))
+                       continue;
+
+               tty_insert_flip_char(tty, c, flag);
+       }
+
+       if (saw_console_brk)
+               sun_do_break();
+
+       return tty;
+}
+
+static void transmit_chars(struct uart_port *port)
+{
+       struct circ_buf *xmit = &port->info->xmit;
+
+       if (uart_circ_empty(xmit) || uart_tx_stopped(port))
+               return;
+
+       while (!uart_circ_empty(xmit)) {
+               long status = hypervisor_con_putchar(xmit->buf[xmit->tail]);
+
+               if (status != HV_EOK)
+                       break;
+
+               xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+               port->icount.tx++;
+       }
+
+       if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+               uart_write_wakeup(port);
+}
+
+static irqreturn_t sunhv_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+       struct uart_port *port = dev_id;
+       struct tty_struct *tty;
+       unsigned long flags;
+
+       spin_lock_irqsave(&port->lock, flags);
+       tty = receive_chars(port, regs);
+       transmit_chars(port);
+       spin_unlock_irqrestore(&port->lock, flags);
+
+       if (tty)
+               tty_flip_buffer_push(tty);
+
+       return IRQ_HANDLED;
+}
+
+/* port->lock is not held.  */
+static unsigned int sunhv_tx_empty(struct uart_port *port)
+{
+       /* Transmitter is always empty for us.  If the circ buffer
+        * is non-empty or there is an x_char pending, our caller
+        * will do the right thing and ignore what we return here.
+        */
+       return TIOCSER_TEMT;
+}
+
+/* port->lock held by caller.  */
+static void sunhv_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+       return;
+}
+
+/* port->lock is held by caller and interrupts are disabled.  */
+static unsigned int sunhv_get_mctrl(struct uart_port *port)
+{
+       return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
+}
+
+/* port->lock held by caller.  */
+static void sunhv_stop_tx(struct uart_port *port)
+{
+       return;
+}
+
+/* port->lock held by caller.  */
+static void sunhv_start_tx(struct uart_port *port)
+{
+       struct circ_buf *xmit = &port->info->xmit;
+       unsigned long flags;
+
+       spin_lock_irqsave(&port->lock, flags);
+
+       while (!uart_circ_empty(xmit)) {
+               long status = hypervisor_con_putchar(xmit->buf[xmit->tail]);
+
+               if (status != HV_EOK)
+                       break;
+
+               xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+               port->icount.tx++;
+       }
+
+       spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/* port->lock is not held.  */
+static void sunhv_send_xchar(struct uart_port *port, char ch)
+{
+       unsigned long flags;
+       int limit = 10000;
+
+       spin_lock_irqsave(&port->lock, flags);
+
+       while (limit-- > 0) {
+               long status = hypervisor_con_putchar(ch);
+               if (status == HV_EOK)
+                       break;
+       }
+
+       spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/* port->lock held by caller.  */
+static void sunhv_stop_rx(struct uart_port *port)
+{
+}
+
+/* port->lock held by caller.  */
+static void sunhv_enable_ms(struct uart_port *port)
+{
+}
+
+/* port->lock is not held.  */
+static void sunhv_break_ctl(struct uart_port *port, int break_state)
+{
+       if (break_state) {
+               unsigned long flags;
+               int limit = 10000;
+
+               spin_lock_irqsave(&port->lock, flags);
+
+               while (limit-- > 0) {
+                       long status = hypervisor_con_putchar(CON_BREAK);
+                       if (status == HV_EOK)
+                               break;
+               }
+
+               spin_unlock_irqrestore(&port->lock, flags);
+       }
+}
+
+/* port->lock is not held.  */
+static int sunhv_startup(struct uart_port *port)
+{
+       return 0;
+}
+
+/* port->lock is not held.  */
+static void sunhv_shutdown(struct uart_port *port)
+{
+}
+
+/* port->lock is not held.  */
+static void sunhv_set_termios(struct uart_port *port, struct termios *termios,
+                             struct termios *old)
+{
+       unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
+       unsigned int quot = uart_get_divisor(port, baud);
+       unsigned int iflag, cflag;
+       unsigned long flags;
+
+       spin_lock_irqsave(&port->lock, flags);
+
+       iflag = termios->c_iflag;
+       cflag = termios->c_cflag;
+
+       port->ignore_status_mask = 0;
+       if (iflag & IGNBRK)
+               port->ignore_status_mask |= IGNORE_BREAK;
+       if ((cflag & CREAD) == 0)
+               port->ignore_status_mask |= IGNORE_ALL;
+
+       /* XXX */
+       uart_update_timeout(port, cflag,
+                           (port->uartclk / (16 * quot)));
+
+       spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *sunhv_type(struct uart_port *port)
+{
+       return "SUN4V HCONS";
+}
+
+static void sunhv_release_port(struct uart_port *port)
+{
+}
+
+static int sunhv_request_port(struct uart_port *port)
+{
+       return 0;
+}
+
+static void sunhv_config_port(struct uart_port *port, int flags)
+{
+}
+
+static int sunhv_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+       return -EINVAL;
+}
+
+static struct uart_ops sunhv_pops = {
+       .tx_empty       = sunhv_tx_empty,
+       .set_mctrl      = sunhv_set_mctrl,
+       .get_mctrl      = sunhv_get_mctrl,
+       .stop_tx        = sunhv_stop_tx,
+       .start_tx       = sunhv_start_tx,
+       .send_xchar     = sunhv_send_xchar,
+       .stop_rx        = sunhv_stop_rx,
+       .enable_ms      = sunhv_enable_ms,
+       .break_ctl      = sunhv_break_ctl,
+       .startup        = sunhv_startup,
+       .shutdown       = sunhv_shutdown,
+       .set_termios    = sunhv_set_termios,
+       .type           = sunhv_type,
+       .release_port   = sunhv_release_port,
+       .request_port   = sunhv_request_port,
+       .config_port    = sunhv_config_port,
+       .verify_port    = sunhv_verify_port,
+};
+
+static struct uart_driver sunhv_reg = {
+       .owner                  = THIS_MODULE,
+       .driver_name            = "serial",
+       .devfs_name             = "tts/",
+       .dev_name               = "ttyS",
+       .major                  = TTY_MAJOR,
+};
+
+static struct uart_port *sunhv_port;
+
+static inline void sunhv_console_putchar(struct uart_port *port, char c)
+{
+       unsigned long flags;
+       int limit = 10000;
+
+       spin_lock_irqsave(&port->lock, flags);
+
+       while (limit-- > 0) {
+               long status = hypervisor_con_putchar(c);
+               if (status == HV_EOK)
+                       break;
+       }
+
+       spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void sunhv_console_write(struct console *con, const char *s, unsigned n)
+{
+       struct uart_port *port = sunhv_port;
+       int i;
+
+       for (i = 0; i < n; i++) {
+               if (*s == '\n')
+                       sunhv_console_putchar(port, '\r');
+               sunhv_console_putchar(port, *s++);
+       }
+}
+
+static int sunhv_console_setup(struct console *con, char *options)
+{
+       return 0;
+}
+
+static struct console sunhv_console = {
+       .name   =       "ttyS",
+       .write  =       sunhv_console_write,
+       .device =       uart_console_device,
+       .setup  =       sunhv_console_setup,
+       .flags  =       CON_PRINTBUFFER,
+       .index  =       -1,
+       .data   =       &sunhv_reg,
+};
+
+static void __init sunhv_console_init(void)
+{
+       if (con_is_present())
+               return;
+
+       sunhv_console.index = 0;
+       register_console(&sunhv_console);
+}
+
+static int __init sunhv_init(void)
+{
+       struct uart_port *port;
+       int ret;
+
+       if (tlb_type != hypervisor)
+               return -ENODEV;
+
+       port = kmalloc(sizeof(struct uart_port), GFP_KERNEL);
+       if (unlikely(!port))
+               return -ENOMEM;
+
+       port->line = 0;
+       port->ops = &sunhv_pops;
+       port->type = PORT_SUNHV;
+       port->uartclk = ( 29491200 / 16 ); /* arbitrary */
+
+       /* XXX Get interrupt. XXX */
+       if (request_irq(0 /* XXX */, sunhv_interrupt,
+                       SA_SHIRQ, "serial(sunhv)", port)) {
+               printk("sunhv: Cannot get IRQ %x\n",
+                      0 /* XXX */);
+               kfree(port);
+               return -ENODEV;
+       }
+
+       sunhv_reg.minor = sunserial_current_minor;
+       sunhv_reg.nr = 1;
+       sunhv_reg.cons = &sunhv_console;
+
+       ret = uart_register_driver(&sunhv_reg);
+       if (ret < 0) {
+               free_irq(0 /* XXX */, up);
+               kfree(port);
+
+               return ret;
+       }
+
+       sunhv_port = port;
+
+       sunserial_current_minor += 1;
+
+       sunhv_console_init();
+
+       uart_add_one_port(&sunhv_reg, port);
+
+       return 0;
+}
+
+static void __exit sunhv_exit(void)
+{
+       struct uart_port *port = sunhv_port;
+
+       BUG_ON(!port);
+
+       uart_remove_one_port(&sunhv_reg, port);
+       free_irq(0 /* XXX */, port);
+
+       sunserial_current_minor -= 1;
+
+       uart_unregister_driver(&sunhv_reg);
+
+       kfree(sunhv_port);
+       sunhv_port = NULL;
+}
+
+module_init(sunhv_init);
+module_exit(sunhv_exit);
+
+MODULE_AUTHOR("David S. Miller");
+MODULE_DESCRIPTION("SUN4V Hypervisor console driver")
+MODULE_LICENSE("GPL");
index 4041122..57abcea 100644 (file)
 /* Hilscher netx */
 #define PORT_NETX      71
 
+/* SUN4V Hypervisor Console */
+#define PORT_SUNHV     72
+
 #ifdef __KERNEL__
 
 #include <linux/config.h>