[MIPS] kpsd and other AP/SP improvements.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

9 files changed, 1307 insertions, 394 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 7b49aa5e8e2..a7bac0459f9 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1476,6 +1476,16 @@ config MIPS_VPE_APSP_API
 	depends on MIPS_VPE_LOADER
 	help
 
+config MIPS_APSP_KSPD
+	bool "Enable KSPD"
+	depends on MIPS_VPE_APSP_API
+	default y
+	help
+	  KSPD is a kernel daemon that accepts syscall requests from the SP
+	  side, actions them and returns the results. It also handles the
+	  "exit" syscall notifying other kernel modules the SP program is
+	  exiting.  You probably want to say yes here.
+
 config SB1_PASS_1_WORKAROUNDS
 	bool
 	depends on CPU_SB1_PASS_1
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 309d54cceda..9ec01de81c0 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_SMP)		+= smp.o
 
 obj-$(CONFIG_MIPS_MT_SMP)	+= smp_mt.o
 
+obj-$(CONFIG_MIPS_APSP_KSPD)	+= kspd.o
 obj-$(CONFIG_MIPS_VPE_LOADER)	+= vpe.o
 obj-$(CONFIG_MIPS_VPE_APSP_API)	+= rtlx.o
 
diff --git a/arch/mips/kernel/kspd.c b/arch/mips/kernel/kspd.c
new file mode 100644
index 00000000000..f06a144c788
--- /dev/null
+++ b/arch/mips/kernel/kspd.c
@@ -0,0 +1,398 @@
+/*
+ * Copyright (C) 2005 MIPS Technologies, Inc.  All rights reserved.
+ *
+ *  This program is free software; you can distribute it and/or modify it
+ *  under the terms of the GNU General Public License (Version 2) as
+ *  published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope it will be useful, but WITHOUT
+ *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ *  for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/unistd.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/syscalls.h>
+#include <linux/workqueue.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+
+#include <asm/vpe.h>
+#include <asm/rtlx.h>
+#include <asm/kspd.h>
+
+static struct workqueue_struct *workqueue = NULL;
+static struct work_struct work;
+
+extern unsigned long cpu_khz;
+
+struct mtsp_syscall {
+	int cmd;
+	unsigned char abi;
+	unsigned char size;
+};
+
+struct mtsp_syscall_ret {
+	int retval;
+	int errno;
+};
+
+struct mtsp_syscall_generic {
+	int arg0;
+	int arg1;
+	int arg2;
+	int arg3;
+	int arg4;
+	int arg5;
+	int arg6;
+};
+
+static struct list_head kspd_notifylist;
+static int sp_stopping = 0;
+
+/* these should match with those in the SDE kit */
+#define MTSP_SYSCALL_BASE	0
+#define MTSP_SYSCALL_EXIT	(MTSP_SYSCALL_BASE + 0)
+#define MTSP_SYSCALL_OPEN	(MTSP_SYSCALL_BASE + 1)
+#define MTSP_SYSCALL_READ	(MTSP_SYSCALL_BASE + 2)
+#define MTSP_SYSCALL_WRITE	(MTSP_SYSCALL_BASE + 3)
+#define MTSP_SYSCALL_CLOSE	(MTSP_SYSCALL_BASE + 4)
+#define MTSP_SYSCALL_LSEEK32	(MTSP_SYSCALL_BASE + 5)
+#define MTSP_SYSCALL_ISATTY	(MTSP_SYSCALL_BASE + 6)
+#define MTSP_SYSCALL_GETTIME	(MTSP_SYSCALL_BASE + 7)
+#define MTSP_SYSCALL_PIPEFREQ	(MTSP_SYSCALL_BASE + 8)
+#define MTSP_SYSCALL_GETTOD	(MTSP_SYSCALL_BASE + 9)
+
+#define MTSP_O_RDONLY		0x0000
+#define MTSP_O_WRONLY		0x0001
+#define MTSP_O_RDWR		0x0002
+#define MTSP_O_NONBLOCK		0x0004
+#define MTSP_O_APPEND		0x0008
+#define MTSP_O_SHLOCK		0x0010
+#define MTSP_O_EXLOCK		0x0020
+#define MTSP_O_ASYNC		0x0040
+#define MTSP_O_FSYNC		O_SYNC
+#define MTSP_O_NOFOLLOW		0x0100
+#define MTSP_O_SYNC		0x0080
+#define MTSP_O_CREAT		0x0200
+#define MTSP_O_TRUNC		0x0400
+#define MTSP_O_EXCL		0x0800
+#define MTSP_O_BINARY		0x8000
+
+#define SP_VPE 1
+
+struct apsp_table  {
+	int sp;
+	int ap;
+};
+
+/* we might want to do the mode flags too */
+struct apsp_table open_flags_table[] = {
+	{ MTSP_O_RDWR, O_RDWR },
+	{ MTSP_O_WRONLY, O_WRONLY },
+	{ MTSP_O_CREAT, O_CREAT },
+	{ MTSP_O_TRUNC, O_TRUNC },
+	{ MTSP_O_NONBLOCK, O_NONBLOCK },
+	{ MTSP_O_APPEND, O_APPEND },
+	{ MTSP_O_NOFOLLOW, O_NOFOLLOW }
+};
+
+struct apsp_table syscall_command_table[] = {
+	{ MTSP_SYSCALL_OPEN, __NR_open },
+	{ MTSP_SYSCALL_CLOSE, __NR_close },
+	{ MTSP_SYSCALL_READ, __NR_read },
+	{ MTSP_SYSCALL_WRITE, __NR_write },
+	{ MTSP_SYSCALL_LSEEK32, __NR_lseek }
+};
+
+static int sp_syscall(int num, int arg0, int arg1, int arg2, int arg3)
+{
+	register long int _num  __asm__ ("$2") = num;
+	register long int _arg0  __asm__ ("$4") = arg0;
+	register long int _arg1  __asm__ ("$5") = arg1;
+	register long int _arg2  __asm__ ("$6") = arg2;
+	register long int _arg3  __asm__ ("$7") = arg3;
+
+	mm_segment_t old_fs;
+
+	old_fs = get_fs();
+ 	set_fs(KERNEL_DS);
+
+  	__asm__ __volatile__ (
+ 	"	syscall					\n"
+ 	: "=r" (_num), "=r" (_arg3)
+ 	: "r" (_num), "r" (_arg0), "r" (_arg1), "r" (_arg2), "r" (_arg3));
+
+	set_fs(old_fs);
+
+	/* $a3 is error flag */
+	if (_arg3)
+		return -_num;
+
+	return _num;
+}
+
+static int translate_syscall_command(int cmd)
+{
+	int i;
+	int ret = -1;
+
+	for (i = 0; i < ARRAY_SIZE(syscall_command_table); i++) {
+		if ((cmd == syscall_command_table[i].sp))
+			return syscall_command_table[i].ap;
+	}
+
+	return ret;
+}
+
+static unsigned int translate_open_flags(int flags)
+{
+	int i;
+	unsigned int ret = 0;
+
+	for (i = 0; i < (sizeof(open_flags_table) / sizeof(struct apsp_table));
+	     i++) {
+		if( (flags & open_flags_table[i].sp) ) {
+			ret |= open_flags_table[i].ap;
+		}
+	}
+
+	return ret;
+}
+
+
+static void sp_setfsuidgid( uid_t uid, gid_t gid)
+{
+	current->fsuid = uid;
+	current->fsgid = gid;
+
+	key_fsuid_changed(current);
+	key_fsgid_changed(current);
+}
+
+/*
+ * Expects a request to be on the sysio channel. Reads it.  Decides whether
+ * its a linux syscall and runs it, or whatever.  Puts the return code back
+ * into the request and sends the whole thing back.
+ */
+void sp_work_handle_request(void)
+{
+	struct mtsp_syscall sc;
+	struct mtsp_syscall_generic generic;
+	struct mtsp_syscall_ret ret;
+	struct kspd_notifications *n;
+	struct timeval tv;
+	struct timezone tz;
+	int cmd;
+
+	char *vcwd;
+	mm_segment_t old_fs;
+	int size;
+
+	ret.retval = -1;
+
+	if (!rtlx_read(RTLX_CHANNEL_SYSIO, &sc, sizeof(struct mtsp_syscall), 0)) {
+		printk(KERN_ERR "Expected request but nothing to read\n");
+		return;
+	}
+
+	size = sc.size;
+
+	if (size) {
+		if (!rtlx_read(RTLX_CHANNEL_SYSIO, &generic, size, 0)) {
+			printk(KERN_ERR "Expected request but nothing to read\n");
+			return;
+		}
+	}
+
+	/* Run the syscall at the priviledge of the user who loaded the
+	   SP program */
+
+	if (vpe_getuid(SP_VPE))
+		sp_setfsuidgid( vpe_getuid(SP_VPE), vpe_getgid(SP_VPE));
+
+	switch (sc.cmd) {
+	/* needs the flags argument translating from SDE kit to
+	   linux */
+ 	case MTSP_SYSCALL_PIPEFREQ:
+ 		ret.retval = cpu_khz * 1000;
+ 		ret.errno = 0;
+ 		break;
+
+ 	case MTSP_SYSCALL_GETTOD:
+ 		memset(&tz, 0, sizeof(tz));
+ 		if ((ret.retval = sp_syscall(__NR_gettimeofday, (int)&tv,
+ 		                             (int)&tz, 0,0)) == 0)
+		ret.retval = tv.tv_sec;
+
+		ret.errno = errno;
+		break;
+
+ 	case MTSP_SYSCALL_EXIT:
+		list_for_each_entry(n, &kspd_notifylist, list)
+ 			n->kspd_sp_exit(SP_VPE);
+		sp_stopping = 1;
+
+		printk(KERN_DEBUG "KSPD got exit syscall from SP exitcode %d\n",
+		       generic.arg0);
+ 		break;
+
+ 	case MTSP_SYSCALL_OPEN:
+ 		generic.arg1 = translate_open_flags(generic.arg1);
+
+ 		vcwd = vpe_getcwd(SP_VPE);
+
+ 		/* change to the cwd of the process that loaded the SP program */
+		old_fs = get_fs();
+		set_fs(KERNEL_DS);
+		sys_chdir(vcwd);
+		set_fs(old_fs);
+
+ 		sc.cmd = __NR_open;
+
+		/* fall through */
+
+  	default:
+ 		if ((sc.cmd >= __NR_Linux) &&
+		    (sc.cmd <= (__NR_Linux +  __NR_Linux_syscalls)) )
+			cmd = sc.cmd;
+		else
+			cmd = translate_syscall_command(sc.cmd);
+
+		if (cmd >= 0) {
+			ret.retval = sp_syscall(cmd, generic.arg0, generic.arg1,
+			                        generic.arg2, generic.arg3);
+			ret.errno = errno;
+		} else
+ 			printk(KERN_WARNING
+			       "KSPD: Unknown SP syscall number %d\n", sc.cmd);
+		break;
+ 	} /* switch */
+
+	if (vpe_getuid(SP_VPE))
+		sp_setfsuidgid( 0, 0);
+
+	if ((rtlx_write(RTLX_CHANNEL_SYSIO, &ret, sizeof(struct mtsp_syscall_ret), 0))
+	    < sizeof(struct mtsp_syscall_ret))
+		printk("KSPD: sp_work_handle_request failed to send to SP\n");
+}
+
+static void sp_cleanup(void)
+{
+	struct files_struct *files = current->files;
+	int i, j;
+	struct fdtable *fdt;
+
+	j = 0;
+
+	/*
+	 * It is safe to dereference the fd table without RCU or
+	 * ->file_lock
+	 */
+	fdt = files_fdtable(files);
+	for (;;) {
+		unsigned long set;
+		i = j * __NFDBITS;
+		if (i >= fdt->max_fdset || i >= fdt->max_fds)
+			break;
+		set = fdt->open_fds->fds_bits[j++];
+		while (set) {
+			if (set & 1) {
+				struct file * file = xchg(&fdt->fd[i], NULL);
+				if (file)
+					filp_close(file, files);
+			}
+			i++;
+			set >>= 1;
+		}
+	}
+}
+
+static int channel_open = 0;
+
+/* the work handler */
+static void sp_work(void *data)
+{
+	if (!channel_open) {
+		if( rtlx_open(RTLX_CHANNEL_SYSIO, 1) != 0) {
+			printk("KSPD: unable to open sp channel\n");
+			sp_stopping = 1;
+		} else {
+			channel_open++;
+			printk(KERN_DEBUG "KSPD: SP channel opened\n");
+		}
+	} else {
+		/* wait for some data, allow it to sleep */
+		rtlx_read_poll(RTLX_CHANNEL_SYSIO, 1);
+
+		/* Check we haven't been woken because we are stopping */
+		if (!sp_stopping)
+			sp_work_handle_request();
+	}
+
+	if (!sp_stopping)
+		queue_work(workqueue, &work);
+	else
+		sp_cleanup();
+}
+
+static void startwork(int vpe)
+{
+	sp_stopping = channel_open = 0;
+
+	if (workqueue == NULL) {
+		if ((workqueue = create_singlethread_workqueue("kspd")) == NULL) {
+			printk(KERN_ERR "unable to start kspd\n");
+			return;
+		}
+
+		INIT_WORK(&work, sp_work, NULL);
+		queue_work(workqueue, &work);
+	} else
+		queue_work(workqueue, &work);
+
+}
+
+static void stopwork(int vpe)
+{
+	sp_stopping = 1;
+
+	printk(KERN_DEBUG "KSPD: SP stopping\n");
+}
+
+void kspd_notify(struct kspd_notifications *notify)
+{
+	list_add(&notify->list, &kspd_notifylist);
+}
+
+static struct vpe_notifications notify;
+static int kspd_module_init(void)
+{
+	INIT_LIST_HEAD(&kspd_notifylist);
+
+	notify.start = startwork;
+	notify.stop = stopwork;
+	vpe_notify(SP_VPE, &notify);
+
+	return 0;
+}
+
+static void kspd_module_exit(void)
+{
+
+}
+
+module_init(kspd_module_init);
+module_exit(kspd_module_exit);
+
+MODULE_DESCRIPTION("MIPS KSPD");
+MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
+MODULE_LICENSE("GPL");
diff --git a/arch/mips/kernel/rtlx.c b/arch/mips/kernel/rtlx.c
index 986a9cf2306..6179805af9f 100644
--- a/arch/mips/kernel/rtlx.c
+++ b/arch/mips/kernel/rtlx.c
@@ -21,45 +21,44 @@
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/init.h>
+#include <asm/uaccess.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/vmalloc.h>
+#include <linux/elf.h>
+#include <linux/seq_file.h>
+#include <linux/syscalls.h>
+#include <linux/moduleloader.h>
 #include <linux/interrupt.h>
-#include <linux/irq.h>
 #include <linux/poll.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
-
 #include <asm/mipsmtregs.h>
-#include <asm/bitops.h>
+#include <asm/cacheflush.h>
+#include <asm/atomic.h>
 #include <asm/cpu.h>
 #include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/vpe.h>
 #include <asm/rtlx.h>
-#include <asm/uaccess.h>
 
 #define RTLX_TARG_VPE 1
 
 static struct rtlx_info *rtlx;
 static int major;
 static char module_name[] = "rtlx";
-static struct irqaction irq;
-static int irq_num;
-
-static inline int spacefree(int read, int write, int size)
-{
-	if (read == write) {
-		/*
-		 * never fill the buffer completely, so indexes are always
-		 * equal if empty and only empty, or !equal if data available
-		 */
-		return size - 1;
-	}
-
-	return ((read + size - write) % size) - 1;
-}
 
 static struct chan_waitqueues {
 	wait_queue_head_t rt_queue;
 	wait_queue_head_t lx_queue;
+	int in_open;
 } channel_wqs[RTLX_CHANNELS];
 
+static struct irqaction irq;
+static int irq_num;
+static struct vpe_notifications notify;
+static int sp_stopping = 0;
+
 extern void *vpe_get_shared(int index);
 
 static void rtlx_dispatch(struct pt_regs *regs)
@@ -67,174 +66,298 @@ static void rtlx_dispatch(struct pt_regs *regs)
 	do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ, regs);
 }
 
+
+/* Interrupt handler may be called before rtlx_init has otherwise had
+   a chance to run.
+*/
 static irqreturn_t rtlx_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
 	int i;
 
 	for (i = 0; i < RTLX_CHANNELS; i++) {
-		struct rtlx_channel *chan = &rtlx->channel[i];
-
-		if (chan->lx_read != chan->lx_write)
-			wake_up_interruptible(&channel_wqs[i].lx_queue);
+			wake_up(&channel_wqs[i].lx_queue);
+			wake_up(&channel_wqs[i].rt_queue);
 	}
 
 	return IRQ_HANDLED;
 }
 
-/* call when we have the address of the shared structure from the SP side. */
-static int rtlx_init(struct rtlx_info *rtlxi)
+static __attribute_used__ void dump_rtlx(void)
 {
 	int i;
 
-	if (rtlxi->id != RTLX_ID) {
-		printk(KERN_WARNING "no valid RTLX id at 0x%p\n", rtlxi);
-		return -ENOEXEC;
-	}
+	printk("id 0x%lx state %d\n", rtlx->id, rtlx->state);
 
-	/* initialise the wait queues */
 	for (i = 0; i < RTLX_CHANNELS; i++) {
-		init_waitqueue_head(&channel_wqs[i].rt_queue);
-		init_waitqueue_head(&channel_wqs[i].lx_queue);
-	}
+		struct rtlx_channel *chan = &rtlx->channel[i];
 
-	/* set up for interrupt handling */
-	memset(&irq, 0, sizeof(struct irqaction));
+		printk(" rt_state %d lx_state %d buffer_size %d\n",
+		       chan->rt_state, chan->lx_state, chan->buffer_size);
 
-	if (cpu_has_vint)
-		set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
+		printk(" rt_read %d rt_write %d\n",
+		       chan->rt_read, chan->rt_write);
 
-	irq_num = MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ;
-	irq.handler = rtlx_interrupt;
-	irq.flags = SA_INTERRUPT;
-	irq.name = "RTLX";
-	irq.dev_id = rtlx;
-	setup_irq(irq_num, &irq);
+		printk(" lx_read %d lx_write %d\n",
+		       chan->lx_read, chan->lx_write);
+
+		printk(" rt_buffer <%s>\n", chan->rt_buffer);
+		printk(" lx_buffer <%s>\n", chan->lx_buffer);
+	}
+}
+
+/* call when we have the address of the shared structure from the SP side. */
+static int rtlx_init(struct rtlx_info *rtlxi)
+{
+	if (rtlxi->id != RTLX_ID) {
+		printk(KERN_ERR "no valid RTLX id at 0x%p 0x%x\n", rtlxi, rtlxi->id);
+		return -ENOEXEC;
+	}
 
 	rtlx = rtlxi;
 
 	return 0;
 }
 
-/* only allow one open process at a time to open each channel */
-static int rtlx_open(struct inode *inode, struct file *filp)
+/* notifications */
+static void starting(int vpe)
 {
-	int minor, ret;
+	int i;
+	sp_stopping = 0;
+
+	/* force a reload of rtlx */
+	rtlx=NULL;
+
+	/* wake up any sleeping rtlx_open's */
+	for (i = 0; i < RTLX_CHANNELS; i++)
+		wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+static void stopping(int vpe)
+{
+	int i;
+
+	sp_stopping = 1;
+	for (i = 0; i < RTLX_CHANNELS; i++)
+		wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+
+int rtlx_open(int index, int can_sleep)
+{
+	int ret;
 	struct rtlx_channel *chan;
+	volatile struct rtlx_info **p;
 
-	/* assume only 1 device at the mo. */
-	minor = MINOR(inode->i_rdev);
+	if (index >= RTLX_CHANNELS) {
+		printk(KERN_DEBUG "rtlx_open index out of range\n");
+		return -ENOSYS;
+	}
+
+	if (channel_wqs[index].in_open) {
+		printk(KERN_DEBUG "rtlx_open channel %d already opened\n", index);
+		return -EBUSY;
+	}
+
+	channel_wqs[index].in_open++;
 
 	if (rtlx == NULL) {
-		struct rtlx_info **p;
 		if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
-			printk(KERN_ERR "vpe_get_shared is NULL. "
-			       "Has an SP program been loaded?\n");
-			return -EFAULT;
+			if (can_sleep) {
+				DECLARE_WAITQUEUE(wait, current);
+
+				/* go to sleep */
+				add_wait_queue(&channel_wqs[index].lx_queue, &wait);
+
+				set_current_state(TASK_INTERRUPTIBLE);
+				while ((p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
+					schedule();
+					set_current_state(TASK_INTERRUPTIBLE);
+				}
+
+				set_current_state(TASK_RUNNING);
+				remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
+
+				/* back running */
+			} else {
+				printk( KERN_DEBUG "No SP program loaded, and device "
+					"opened with O_NONBLOCK\n");
+				channel_wqs[index].in_open = 0;
+				return -ENOSYS;
+			}
 		}
 
 		if (*p == NULL) {
-			printk(KERN_ERR "vpe_shared %p %p\n", p, *p);
-			return -EFAULT;
+			if (can_sleep) {
+				DECLARE_WAITQUEUE(wait, current);
+
+				/* go to sleep */
+				add_wait_queue(&channel_wqs[index].lx_queue, &wait);
+
+				set_current_state(TASK_INTERRUPTIBLE);
+				while (*p == NULL) {
+					schedule();
+
+					/* reset task state to interruptable otherwise
+					   we'll whizz round here like a very fast loopy
+					   thing. schedule() appears to return with state
+					   set to TASK_RUNNING.
+
+					   If the loaded SP program, for whatever reason,
+					   doesn't set up the shared structure *p will never
+					   become true. So whoever connected to either /dev/rt?
+					   or if it was kspd, will then take up rather a lot of
+					   processor cycles.
+					*/
+
+					set_current_state(TASK_INTERRUPTIBLE);
+				}
+
+				set_current_state(TASK_RUNNING);
+				remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
+
+				/* back running */
+			}
+			else {
+				printk(" *vpe_get_shared is NULL. "
+				       "Has an SP program been loaded?\n");
+				channel_wqs[index].in_open = 0;
+				return -ENOSYS;
+			}
+		}
+
+		if ((unsigned int)*p < KSEG0) {
+			printk(KERN_WARNING "vpe_get_shared returned an invalid pointer "
+			       "maybe an error code %d\n", (int)*p);
+ 			channel_wqs[index].in_open = 0;
+			return -ENOSYS;
 		}
 
-		if ((ret = rtlx_init(*p)) < 0)
-			return ret;
+ 		if ((ret = rtlx_init(*p)) < 0) {
+ 			channel_wqs[index].in_open = 0;
+  			return ret;
+ 		}
 	}
 
-	chan = &rtlx->channel[minor];
+	chan = &rtlx->channel[index];
 
-	if (test_and_set_bit(RTLX_STATE_OPENED, &chan->lx_state))
-		return -EBUSY;
+ 	if (chan->lx_state == RTLX_STATE_OPENED) {
+ 		channel_wqs[index].in_open = 0;
+  		return -EBUSY;
+ 	}
 
+  	chan->lx_state = RTLX_STATE_OPENED;
+ 	channel_wqs[index].in_open = 0;
 	return 0;
 }
 
-static int rtlx_release(struct inode *inode, struct file *filp)
+int rtlx_release(int index)
 {
-	int minor = MINOR(inode->i_rdev);
-
-	clear_bit(RTLX_STATE_OPENED, &rtlx->channel[minor].lx_state);
-	smp_mb__after_clear_bit();
-
+	rtlx->channel[index].lx_state = RTLX_STATE_UNUSED;
 	return 0;
 }
 
-static unsigned int rtlx_poll(struct file *file, poll_table * wait)
+unsigned int rtlx_read_poll(int index, int can_sleep)
 {
-	int minor;
-	unsigned int mask = 0;
-	struct rtlx_channel *chan;
+ 	struct rtlx_channel *chan;
 
-	minor = MINOR(file->f_dentry->d_inode->i_rdev);
-	chan = &rtlx->channel[minor];
+ 	if (rtlx == NULL)
+ 		return 0;
 
-	poll_wait(file, &channel_wqs[minor].rt_queue, wait);
-	poll_wait(file, &channel_wqs[minor].lx_queue, wait);
+ 	chan = &rtlx->channel[index];
 
 	/* data available to read? */
-	if (chan->lx_read != chan->lx_write)
-		mask |= POLLIN | POLLRDNORM;
+	if (chan->lx_read == chan->lx_write) {
+		if (can_sleep) {
+			DECLARE_WAITQUEUE(wait, current);
 
-	/* space to write */
-	if (spacefree(chan->rt_read, chan->rt_write, chan->buffer_size))
-		mask |= POLLOUT | POLLWRNORM;
+			/* go to sleep */
+			add_wait_queue(&channel_wqs[index].lx_queue, &wait);
 
-	return mask;
+			set_current_state(TASK_INTERRUPTIBLE);
+			while (chan->lx_read == chan->lx_write) {
+				schedule();
+
+				set_current_state(TASK_INTERRUPTIBLE);
+
+				if (sp_stopping) {
+					set_current_state(TASK_RUNNING);
+					remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
+					return 0;
+				}
+			}
+
+			set_current_state(TASK_RUNNING);
+			remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
+
+			/* back running */
+		}
+		else
+			return 0;
+	}
+
+	return (chan->lx_write + chan->buffer_size - chan->lx_read)
+	       % chan->buffer_size;
 }
 
-static ssize_t rtlx_read(struct file *file, char __user * buffer, size_t count,
-			 loff_t * ppos)
+static inline int write_spacefree(int read, int write, int size)
 {
-	unsigned long failed;
-	size_t fl = 0L;
-	int minor;
-	struct rtlx_channel *lx;
-	DECLARE_WAITQUEUE(wait, current);
+	if (read == write) {
+		/*
+		 * Never fill the buffer completely, so indexes are always
+		 * equal if empty and only empty, or !equal if data available
+		 */
+		return size - 1;
+	}
 
-	minor = MINOR(file->f_dentry->d_inode->i_rdev);
-	lx = &rtlx->channel[minor];
+	return ((read + size - write) % size) - 1;
+}
 
-	/* data available? */
-	if (lx->lx_write == lx->lx_read) {
-		if (file->f_flags & O_NONBLOCK)
-			return 0;	/* -EAGAIN makes cat whinge */
+unsigned int rtlx_write_poll(int index)
+{
+	struct rtlx_channel *chan = &rtlx->channel[index];
+	return write_spacefree(chan->rt_read, chan->rt_write, chan->buffer_size);
+}
 
-		/* go to sleep */
-		add_wait_queue(&channel_wqs[minor].lx_queue, &wait);
-		set_current_state(TASK_INTERRUPTIBLE);
+static inline void copy_to(void *dst, void *src, size_t count, int user)
+{
+	if (user)
+		copy_to_user(dst, src, count);
+	else
+		memcpy(dst, src, count);
+}
 
-		while (lx->lx_write == lx->lx_read)
-			schedule();
+static inline void copy_from(void *dst, void *src, size_t count, int user)
+{
+	if (user)
+		copy_from_user(dst, src, count);
+	else
+		memcpy(dst, src, count);
+}
 
-		set_current_state(TASK_RUNNING);
-		remove_wait_queue(&channel_wqs[minor].lx_queue, &wait);
+ssize_t rtlx_read(int index, void *buff, size_t count, int user)
+{
+	size_t fl = 0L;
+	struct rtlx_channel *lx;
 
-		/* back running */
-	}
+	if (rtlx == NULL)
+		return -ENOSYS;
+
+	lx = &rtlx->channel[index];
 
 	/* find out how much in total */
 	count = min(count,
-		    (size_t)(lx->lx_write + lx->buffer_size - lx->lx_read) % lx->buffer_size);
+		     (size_t)(lx->lx_write + lx->buffer_size - lx->lx_read)
+		     % lx->buffer_size);
 
 	/* then how much from the read pointer onwards */
-	fl = min(count, (size_t)lx->buffer_size - lx->lx_read);
+	fl = min( count, (size_t)lx->buffer_size - lx->lx_read);
 
-	failed = copy_to_user (buffer, &lx->lx_buffer[lx->lx_read], fl);
-	if (failed) {
-		count = fl - failed;
-		goto out;
-	}
+	copy_to(buff, &lx->lx_buffer[lx->lx_read], fl, user);
 
 	/* and if there is anything left at the beginning of the buffer */
-	if (count - fl) {
-		failed = copy_to_user (buffer + fl, lx->lx_buffer, count - fl);
-		if (failed) {
-			count -= failed;
-			goto out;
-		}
-	}
+	if ( count - fl )
+		copy_to (buff + fl, lx->lx_buffer, count - fl, user);
 
-out:
 	/* update the index */
 	lx->lx_read += count;
 	lx->lx_read %= lx->buffer_size;
@@ -242,20 +365,101 @@ out:
 	return count;
 }
 
-static ssize_t rtlx_write(struct file *file, const char __user * buffer,
+ssize_t rtlx_write(int index, void *buffer, size_t count, int user)
+{
+	struct rtlx_channel *rt;
+	size_t fl;
+
+	if (rtlx == NULL)
+		return(-ENOSYS);
+
+	rt = &rtlx->channel[index];
+
+	/* total number of bytes to copy */
+	count = min(count,
+		    (size_t)write_spacefree(rt->rt_read, rt->rt_write,
+					    rt->buffer_size));
+
+	/* first bit from write pointer to the end of the buffer, or count */
+	fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
+
+	copy_from (&rt->rt_buffer[rt->rt_write], buffer, fl, user);
+
+	/* if there's any left copy to the beginning of the buffer */
+	if( count - fl )
+		copy_from (rt->rt_buffer, buffer + fl, count - fl, user);
+
+	rt->rt_write += count;
+	rt->rt_write %= rt->buffer_size;
+
+	return(count);
+}
+
+
+static int file_open(struct inode *inode, struct file *filp)
+{
+	int minor = MINOR(inode->i_rdev);
+
+	return rtlx_open(minor, (filp->f_flags & O_NONBLOCK) ? 0 : 1);
+}
+
+static int file_release(struct inode *inode, struct file *filp)
+{
+	int minor;
+	minor = MINOR(inode->i_rdev);
+
+	return rtlx_release(minor);
+}
+
+static unsigned int file_poll(struct file *file, poll_table * wait)
+{
+	int minor;
+	unsigned int mask = 0;
+
+	minor = MINOR(file->f_dentry->d_inode->i_rdev);
+
+	poll_wait(file, &channel_wqs[minor].rt_queue, wait);
+	poll_wait(file, &channel_wqs[minor].lx_queue, wait);
+
+	if (rtlx == NULL)
+		return 0;
+
+	/* data available to read? */
+	if (rtlx_read_poll(minor, 0))
+		mask |= POLLIN | POLLRDNORM;
+
+	/* space to write */
+	if (rtlx_write_poll(minor))
+		mask |= POLLOUT | POLLWRNORM;
+
+	return mask;
+}
+
+static ssize_t file_read(struct file *file, char __user * buffer, size_t count,
+			 loff_t * ppos)
+{
+	int minor = MINOR(file->f_dentry->d_inode->i_rdev);
+
+	/* data available? */
+	if (!rtlx_read_poll(minor, (file->f_flags & O_NONBLOCK) ? 0 : 1)) {
+		return 0;	// -EAGAIN makes cat whinge
+	}
+
+	return rtlx_read(minor, buffer, count, 1);
+}
+
+static ssize_t file_write(struct file *file, const char __user * buffer,
 			  size_t count, loff_t * ppos)
 {
-	unsigned long failed;
 	int minor;
 	struct rtlx_channel *rt;
-	size_t fl;
 	DECLARE_WAITQUEUE(wait, current);
 
 	minor = MINOR(file->f_dentry->d_inode->i_rdev);
 	rt = &rtlx->channel[minor];
 
 	/* any space left... */
-	if (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size)) {
+	if (!rtlx_write_poll(minor)) {
 
 		if (file->f_flags & O_NONBLOCK)
 			return -EAGAIN;
@@ -263,61 +467,64 @@ static ssize_t rtlx_write(struct file *file, const char __user * buffer,
 		add_wait_queue(&channel_wqs[minor].rt_queue, &wait);
 		set_current_state(TASK_INTERRUPTIBLE);
 
-		while (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size))
+		while (!rtlx_write_poll(minor))
 			schedule();
 
 		set_current_state(TASK_RUNNING);
 		remove_wait_queue(&channel_wqs[minor].rt_queue, &wait);
 	}
 
-	/* total number of bytes to copy */
-	count = min(count, (size_t)spacefree(rt->rt_read, rt->rt_write, rt->buffer_size) );
-
-	/* first bit from write pointer to the end of the buffer, or count */
-	fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
-
-	failed = copy_from_user(&rt->rt_buffer[rt->rt_write], buffer, fl);
-	if (failed) {
-		count = fl - failed;
-		goto out;
-	}
-
-	/* if there's any left copy to the beginning of the buffer */
-	if (count - fl) {
-		failed = copy_from_user(rt->rt_buffer, buffer + fl, count - fl);
-		if (failed) {
-			count -= failed;
-			goto out;
-		}
-	}
-
-out:
-	rt->rt_write += count;
-	rt->rt_write %= rt->buffer_size;
-
-	return count;
+	return rtlx_write(minor, (void *)buffer, count, 1);
 }
 
 static struct file_operations rtlx_fops = {
-	.owner		= THIS_MODULE,
-	.open		= rtlx_open,
-	.release	= rtlx_release,
-	.write		= rtlx_write,
-	.read		= rtlx_read,
-	.poll		= rtlx_poll
+	.owner =   THIS_MODULE,
+	.open =    file_open,
+	.release = file_release,
+	.write =   file_write,
+	.read =    file_read,
+	.poll =    file_poll
 };
 
+static struct irqaction rtlx_irq = {
+	.handler	= rtlx_interrupt,
+	.flags		= SA_INTERRUPT,
+	.name		= "RTLX",
+};
+
+static int rtlx_irq_num = MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ;
+
 static char register_chrdev_failed[] __initdata =
 	KERN_ERR "rtlx_module_init: unable to register device\n";
 
-static int __init rtlx_module_init(void)
+static int rtlx_module_init(void)
 {
+	int i;
+
 	major = register_chrdev(0, module_name, &rtlx_fops);
 	if (major < 0) {
 		printk(register_chrdev_failed);
 		return major;
 	}
 
+	/* initialise the wait queues */
+	for (i = 0; i < RTLX_CHANNELS; i++) {
+		init_waitqueue_head(&channel_wqs[i].rt_queue);
+		init_waitqueue_head(&channel_wqs[i].lx_queue);
+		channel_wqs[i].in_open = 0;
+	}
+
+	/* set up notifiers */
+	notify.start = starting;
+	notify.stop = stopping;
+	vpe_notify(RTLX_TARG_VPE, &notify);
+
+	if (cpu_has_vint)
+		set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
+
+	rtlx_irq.dev_id = rtlx;
+	setup_irq(rtlx_irq_num, &rtlx_irq);
+
 	return 0;
 }
 
@@ -330,5 +537,5 @@ module_init(rtlx_module_init);
 module_exit(rtlx_module_exit);
 
 MODULE_DESCRIPTION("MIPS RTLX");
-MODULE_AUTHOR("Elizabeth Clarke, MIPS Technologies, Inc.");
+MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
 MODULE_LICENSE("GPL");
diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
index ae83b755cf4..80ffaa6d50a 100644
--- a/arch/mips/kernel/vpe.c
+++ b/arch/mips/kernel/vpe.c
@@ -13,7 +13,6 @@
  *  You should have received a copy of the GNU General Public License along
  *  with this program; if not, write to the Free Software Foundation, Inc.,
  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
- *
  */
 
 /*
@@ -27,11 +26,8 @@
  *
  * To load and run, simply cat a SP 'program file' to /dev/vpe1.
  * i.e cat spapp >/dev/vpe1.
- *
- * You'll need to have the following device files.
- * mknod /dev/vpe0 c 63 0
- * mknod /dev/vpe1 c 63 1
  */
+
 #include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -55,6 +51,8 @@
 #include <asm/cpu.h>
 #include <asm/processor.h>
 #include <asm/system.h>
+#include <asm/vpe.h>
+#include <asm/kspd.h>
 
 typedef void *vpe_handle;
 
@@ -68,6 +66,11 @@ typedef void *vpe_handle;
 static char module_name[] = "vpe";
 static int major;
 
+#ifdef CONFIG_MIPS_APSP_KSPD
+ static struct kspd_notifications kspd_events;
+static int kspd_events_reqd = 0;
+#endif