patch-2.4.22 linux-2.4.22/drivers/acpi/osl.c

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diff -urN linux-2.4.21/drivers/acpi/osl.c linux-2.4.22/drivers/acpi/osl.c
@@ -0,0 +1,1023 @@
+/*
+ *  acpi_osl.c - OS-dependent functions ($Revision: 80 $)
+ *
+ *  Copyright (C) 2000       Andrew Henroid
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that 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/config.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/kmod.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/nmi.h>
+#include <asm/io.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi.h>
+
+#ifdef CONFIG_ACPI_EFI
+#include <linux/efi.h>
+u64 efi_mem_attributes (u64 phys_addr);
+#endif
+
+
+#define _COMPONENT		ACPI_OS_SERVICES
+ACPI_MODULE_NAME	("osl")
+
+#define PREFIX		"ACPI: "
+
+struct acpi_os_dpc
+{
+    OSD_EXECUTION_CALLBACK  function;
+    void		    *context;
+};
+
+
+#ifdef ENABLE_DEBUGGER
+#include <linux/kdb.h>
+/* stuff for debugger support */
+int acpi_in_debugger = 0;
+extern char line_buf[80];
+#endif /*ENABLE_DEBUGGER*/
+
+static int acpi_irq_irq = 0;
+static OSD_HANDLER acpi_irq_handler = NULL;
+static void *acpi_irq_context = NULL;
+
+
+acpi_status
+acpi_os_initialize(void)
+{
+	/*
+	 * Initialize PCI configuration space access, as we'll need to access
+	 * it while walking the namespace (bus 0 and root bridges w/ _BBNs).
+	 */
+#ifdef CONFIG_ACPI_PCI
+	pcibios_config_init();
+	if (!pci_config_read || !pci_config_write) {
+		printk(KERN_ERR PREFIX "Access to PCI configuration space unavailable\n");
+		return AE_NULL_ENTRY;
+	}
+#endif
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_terminate(void)
+{
+	if (acpi_irq_handler) {
+		acpi_os_remove_interrupt_handler(acpi_irq_irq,
+						 acpi_irq_handler);
+	}
+
+	return AE_OK;
+}
+
+void
+acpi_os_printf(const char *fmt,...)
+{
+	va_list args;
+	va_start(args, fmt);
+	acpi_os_vprintf(fmt, args);
+	va_end(args);
+}
+
+void
+acpi_os_vprintf(const char *fmt, va_list args)
+{
+	static char buffer[512];
+	
+	vsprintf(buffer, fmt, args);
+
+#ifdef ENABLE_DEBUGGER
+	if (acpi_in_debugger) {
+		kdb_printf("%s", buffer);
+	} else {
+		printk("%s", buffer);
+	}
+#else
+	printk("%s", buffer);
+#endif
+}
+
+void *
+acpi_os_allocate(acpi_size size)
+{
+	return kmalloc(size, GFP_KERNEL);
+}
+
+void
+acpi_os_free(void *ptr)
+{
+	kfree(ptr);
+}
+
+acpi_status
+acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
+{
+#ifdef CONFIG_ACPI_EFI
+	addr->pointer_type = ACPI_PHYSICAL_POINTER;
+	if (efi.acpi20)
+		addr->pointer.physical = (acpi_physical_address) virt_to_phys(efi.acpi20);
+	else if (efi.acpi)
+		addr->pointer.physical = (acpi_physical_address) virt_to_phys(efi.acpi);
+	else {
+		printk(KERN_ERR PREFIX "System description tables not found\n");
+		return AE_NOT_FOUND;
+	}
+#else
+	if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
+		printk(KERN_ERR PREFIX "System description tables not found\n");
+		return AE_NOT_FOUND;
+	}
+#endif /*CONFIG_ACPI_EFI*/
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_map_memory(acpi_physical_address phys, acpi_size size, void **virt)
+{
+#ifdef CONFIG_ACPI_EFI
+	if (EFI_MEMORY_WB & efi_mem_attributes(phys)) {
+		*virt = phys_to_virt(phys);
+	} else {
+		*virt = ioremap(phys, size);
+	}
+#else
+	if (phys > ULONG_MAX) {
+		printk(KERN_ERR PREFIX "Cannot map memory that high\n");
+		return AE_BAD_PARAMETER;
+	}
+	/*
+	 * ioremap checks to ensure this is in reserved space
+	 */
+	*virt = ioremap((unsigned long) phys, size);
+#endif
+
+	if (!*virt)
+		return AE_NO_MEMORY;
+
+	return AE_OK;
+}
+
+void
+acpi_os_unmap_memory(void *virt, acpi_size size)
+{
+	iounmap(virt);
+}
+
+acpi_status
+acpi_os_get_physical_address(void *virt, acpi_physical_address *phys)
+{
+	if(!phys || !virt)
+		return AE_BAD_PARAMETER;
+
+	*phys = virt_to_phys(virt);
+
+	return AE_OK;
+}
+
+#define ACPI_MAX_OVERRIDE_LEN 100
+
+static char __initdata acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
+
+acpi_status
+acpi_os_predefined_override (const struct acpi_predefined_names *init_val,
+		             acpi_string *new_val)
+{
+	if (!init_val || !new_val)
+		return AE_BAD_PARAMETER;
+
+	*new_val = NULL;
+	if (!memcmp (init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
+		printk(KERN_INFO PREFIX "Overriding _OS definition: %s\n",
+		       acpi_os_name);
+		*new_val = acpi_os_name;
+	}
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_table_override (struct acpi_table_header *existing_table,
+			struct acpi_table_header **new_table)
+{
+	if (!existing_table || !new_table)
+		return AE_BAD_PARAMETER;
+
+	*new_table = NULL;
+	return AE_OK;
+}
+
+static void
+acpi_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+	(*acpi_irq_handler)(acpi_irq_context);
+}
+
+acpi_status
+acpi_os_install_interrupt_handler(u32 irq, OSD_HANDLER handler, void *context)
+{
+	/*
+	 * Ignore the irq from the core, and use the value in our copy of the
+	 * FADT. It may not be the same if an interrupt source override exists
+	 * for the SCI.
+	 */
+	irq = acpi_fadt.sci_int;
+
+#ifdef CONFIG_IA64
+	irq = acpi_irq_to_vector(irq);
+	if (irq < 0) {
+		printk(KERN_ERR PREFIX "SCI (ACPI interrupt %d) not registered\n",
+		       acpi_fadt.sci_int);
+		return AE_OK;
+	}
+#endif
+	acpi_irq_irq = irq;
+	acpi_irq_handler = handler;
+	acpi_irq_context = context;
+	if (request_irq(irq, acpi_irq, SA_SHIRQ, "acpi", acpi_irq)) {
+		printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq);
+		return AE_NOT_ACQUIRED;
+	}
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_remove_interrupt_handler(u32 irq, OSD_HANDLER handler)
+{
+	if (acpi_irq_handler) {
+#ifdef CONFIG_IA64
+		irq = acpi_irq_to_vector(irq);
+#endif
+		free_irq(irq, acpi_irq);
+		acpi_irq_handler = NULL;
+	}
+
+	return AE_OK;
+}
+
+/*
+ * Running in interpreter thread context, safe to sleep
+ */
+
+void
+acpi_os_sleep(u32 sec, u32 ms)
+{
+	current->state = TASK_INTERRUPTIBLE;
+	schedule_timeout(HZ * sec + (ms * HZ) / 1000);
+}
+
+void
+acpi_os_stall(u32 us)
+{
+	while (us) {
+		u32 delay = 1000;
+
+		if (delay > us)
+			delay = us;
+		udelay(delay);
+		touch_nmi_watchdog();
+		us -= delay;
+	}
+}
+
+acpi_status
+acpi_os_read_port(
+	acpi_io_address	port,
+	u32		*value,
+	u32		width)
+{
+	u32 dummy;
+
+	if (!value)
+		value = &dummy;
+
+	switch (width)
+	{
+	case 8:
+		*(u8*)  value = inb(port);
+		break;
+	case 16:
+		*(u16*) value = inw(port);
+		break;
+	case 32:
+		*(u32*) value = inl(port);
+		break;
+	default:
+		BUG();
+	}
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_write_port(
+	acpi_io_address	port,
+	u32		value,
+	u32		width)
+{
+	switch (width)
+	{
+	case 8:
+		outb(value, port);
+		break;
+	case 16:
+		outw(value, port);
+		break;
+	case 32:
+		outl(value, port);
+		break;
+	default:
+		BUG();
+	}
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_read_memory(
+	acpi_physical_address	phys_addr,
+	u32			*value,
+	u32			width)
+{
+	u32			dummy;
+	void			*virt_addr;
+
+#ifdef CONFIG_ACPI_EFI
+	int			iomem = 0;
+
+	if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+		virt_addr = phys_to_virt(phys_addr);
+	} else {
+		iomem = 1;
+		virt_addr = ioremap(phys_addr, width);
+	}
+#else
+	virt_addr = phys_to_virt(phys_addr);
+#endif
+	if (!value)
+		value = &dummy;
+
+	switch (width) {
+	case 8:
+		*(u8*) value = *(u8*) virt_addr;
+		break;
+	case 16:
+		*(u16*) value = *(u16*) virt_addr;
+		break;
+	case 32:
+		*(u32*) value = *(u32*) virt_addr;
+		break;
+	default:
+		BUG();
+	}
+
+#ifdef CONFIG_ACPI_EFI
+	if (iomem)
+		iounmap(virt_addr);
+#endif
+
+	return AE_OK;
+}
+
+acpi_status
+acpi_os_write_memory(
+	acpi_physical_address	phys_addr,
+	u32			value,
+	u32			width)
+{
+	void			*virt_addr;
+
+#ifdef CONFIG_ACPI_EFI
+	int			iomem = 0;
+
+	if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+		virt_addr = phys_to_virt(phys_addr);
+	} else {
+		iomem = 1;
+		virt_addr = ioremap(phys_addr, width);
+	}
+#else
+	virt_addr = phys_to_virt(phys_addr);
+#endif
+
+	switch (width) {
+	case 8:
+		*(u8*) virt_addr = value;
+		break;
+	case 16:
+		*(u16*) virt_addr = value;
+		break;
+	case 32:
+		*(u32*) virt_addr = value;
+		break;
+	default:
+		BUG();
+	}
+
+#ifdef CONFIG_ACPI_EFI
+	if (iomem)
+		iounmap(virt_addr);
+#endif
+
+	return AE_OK;
+}
+
+#ifdef CONFIG_ACPI_PCI
+
+acpi_status
+acpi_os_read_pci_configuration (
+	struct acpi_pci_id	*pci_id,
+	u32			reg,
+	void			*value,
+	u32			width)
+{
+	int			result = 0;
+	if (!value)
+		return AE_BAD_PARAMETER;
+
+	switch (width)
+	{
+	case 8:
+		result = pci_config_read(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 1, value);
+		break;
+	case 16:
+		result = pci_config_read(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 2, value);
+		break;
+	case 32:
+		result = pci_config_read(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 4, value);
+		break;
+	default:
+		BUG();
+	}
+
+	return (result ? AE_ERROR : AE_OK);
+}
+
+acpi_status
+acpi_os_write_pci_configuration (
+	struct acpi_pci_id	*pci_id,
+	u32			reg,
+	acpi_integer		value,
+	u32			width)
+{
+	int			result = 0;
+
+	switch (width)
+	{
+	case 8:
+		result = pci_config_write(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 1, value);
+		break;
+	case 16:
+		result = pci_config_write(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 2, value);
+		break;
+	case 32:
+		result = pci_config_write(pci_id->segment, pci_id->bus,
+			pci_id->device, pci_id->function, reg, 4, value);
+		break;
+	default:
+		BUG();
+	}
+
+	return (result ? AE_ERROR : AE_OK);
+}
+
+static void
+acpi_os_derive_pci_id_2 (
+	acpi_handle		rhandle,        /* upper bound  */
+	acpi_handle		chandle,        /* current node */
+	struct acpi_pci_id	**id,
+	int			*is_bridge,
+	u8			*bus_number)
+{
+	acpi_handle		handle;
+	struct acpi_pci_id	*pci_id = *id;
+	acpi_status		status;
+	unsigned long		temp;
+	acpi_object_type	type;
+	u8			tu8;
+
+	acpi_get_parent(chandle, &handle);
+	if (handle != rhandle) {
+		acpi_os_derive_pci_id_2(rhandle, handle, &pci_id, is_bridge, bus_number);
+
+		status = acpi_get_type(handle, &type);
+		if ( (ACPI_FAILURE(status)) || (type != ACPI_TYPE_DEVICE) )
+			return;
+
+		status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &temp);
+		if (ACPI_SUCCESS(status)) {
+			pci_id->device  = ACPI_HIWORD (ACPI_LODWORD (temp));
+			pci_id->function = ACPI_LOWORD (ACPI_LODWORD (temp));
+
+			if (*is_bridge)
+				pci_id->bus = *bus_number;
+
+			/* any nicer way to get bus number of bridge ? */
+			status = acpi_os_read_pci_configuration(pci_id, 0x0e, &tu8, 8);
+			if (ACPI_SUCCESS(status) &&
+			    ((tu8 & 0x7f) == 1 || (tu8 & 0x7f) == 2)) {
+				status = acpi_os_read_pci_configuration(pci_id, 0x18, &tu8, 8);
+				if (!ACPI_SUCCESS(status)) {
+					/* Certainly broken...  FIX ME */
+					return;
+				}
+				*is_bridge = 1;
+				pci_id->bus = tu8;
+				status = acpi_os_read_pci_configuration(pci_id, 0x19, &tu8, 8);
+				if (ACPI_SUCCESS(status)) {
+					*bus_number = tu8;
+				}
+			} else
+				*is_bridge = 0;
+		}
+	}
+}
+
+void
+acpi_os_derive_pci_id (
+	acpi_handle		rhandle,        /* upper bound  */
+	acpi_handle		chandle,        /* current node */
+	struct acpi_pci_id	**id)
+{
+	int is_bridge = 1;
+	u8 bus_number = (*id)->bus;
+
+	acpi_os_derive_pci_id_2(rhandle, chandle, id, &is_bridge, &bus_number);
+}
+
+#else /*!CONFIG_ACPI_PCI*/
+
+acpi_status
+acpi_os_write_pci_configuration (
+	struct acpi_pci_id	*pci_id,
+	u32			reg,
+	acpi_integer		value,
+	u32			width)
+{
+	return (AE_SUPPORT);
+}
+
+acpi_status
+acpi_os_read_pci_configuration (
+	struct acpi_pci_id	*pci_id,
+	u32			reg,
+	void			*value,
+	u32			width)
+{
+	return (AE_SUPPORT);
+}
+
+void
+acpi_os_derive_pci_id (
+	acpi_handle		rhandle,        /* upper bound  */
+	acpi_handle		chandle,        /* current node */
+	struct acpi_pci_id	**id)
+{
+}
+
+#endif /*CONFIG_ACPI_PCI*/
+
+static void
+acpi_os_execute_deferred (
+	void *context)
+{
+	struct acpi_os_dpc	*dpc = NULL;
+
+	ACPI_FUNCTION_TRACE ("os_execute_deferred");
+
+	dpc = (struct acpi_os_dpc *) context;
+	if (!dpc) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Invalid (NULL) context.\n"));
+		return_VOID;
+	}
+
+	dpc->function(dpc->context);
+
+	kfree(dpc);
+
+	return_VOID;
+}
+
+acpi_status
+acpi_os_queue_for_execution(
+	u32			priority,
+	OSD_EXECUTION_CALLBACK	function,
+	void			*context)
+{
+	acpi_status 		status = AE_OK;
+	struct acpi_os_dpc	*dpc = NULL;
+	struct tq_struct	*task;
+
+	ACPI_FUNCTION_TRACE ("os_queue_for_execution");
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Scheduling function [%p(%p)] for deferred execution.\n", function, context));
+
+	if (!function)
+		return_ACPI_STATUS (AE_BAD_PARAMETER);
+
+	/*
+	 * Allocate/initialize DPC structure.  Note that this memory will be
+	 * freed by the callee.  The kernel handles the tq_struct list  in a
+	 * way that allows us to also free its memory inside the callee.
+	 * Because we may want to schedule several tasks with different
+	 * parameters we can't use the approach some kernel code uses of
+	 * having a static tq_struct.
+	 * We can save time and code by allocating the DPC and tq_structs
+	 * from the same memory.
+	 */
+	dpc = kmalloc(sizeof(struct acpi_os_dpc)+sizeof(struct tq_struct), GFP_ATOMIC);
+	if (!dpc)
+		return_ACPI_STATUS (AE_NO_MEMORY);
+
+	dpc->function = function;
+	dpc->context = context;
+
+	task = (void *)(dpc+1);
+	INIT_TQUEUE(task, acpi_os_execute_deferred, (void*)dpc);
+
+	if (!schedule_task(task)) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Call to schedule_task() failed.\n"));
+		kfree(dpc);
+		status = AE_ERROR;
+	}
+
+	return_ACPI_STATUS (status);
+}
+
+/*
+ * Allocate the memory for a spinlock and initialize it.
+ */
+acpi_status
+acpi_os_create_lock (
+	acpi_handle	*out_handle)
+{
+	spinlock_t *lock_ptr;
+
+	ACPI_FUNCTION_TRACE ("os_create_lock");
+
+	lock_ptr = acpi_os_allocate(sizeof(spinlock_t));
+
+	spin_lock_init(lock_ptr);
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Creating spinlock[%p].\n", lock_ptr));
+
+	*out_handle = lock_ptr;
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+
+/*
+ * Deallocate the memory for a spinlock.
+ */
+void
+acpi_os_delete_lock (
+	acpi_handle	handle)
+{
+	ACPI_FUNCTION_TRACE ("os_create_lock");
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Deleting spinlock[%p].\n", handle));
+
+	acpi_os_free(handle);
+
+	return_VOID;
+}
+
+/*
+ * Acquire a spinlock.
+ *
+ * handle is a pointer to the spinlock_t.
+ * flags is *not* the result of save_flags - it is an ACPI-specific flag variable
+ *   that indicates whether we are at interrupt level.
+ */
+void
+acpi_os_acquire_lock (
+	acpi_handle	handle,
+	u32		flags)
+{
+	ACPI_FUNCTION_TRACE ("os_acquire_lock");
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Acquiring spinlock[%p] from %s level\n", handle,
+		((flags & ACPI_NOT_ISR) ? "non-interrupt" : "interrupt")));
+
+	if (flags & ACPI_NOT_ISR)
+		ACPI_DISABLE_IRQS();
+
+	spin_lock((spinlock_t *)handle);
+
+	return_VOID;
+}
+
+
+/*
+ * Release a spinlock. See above.
+ */
+void
+acpi_os_release_lock (
+	acpi_handle	handle,
+	u32		flags)
+{
+	ACPI_FUNCTION_TRACE ("os_release_lock");
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Releasing spinlock[%p] from %s level\n", handle,
+		((flags & ACPI_NOT_ISR) ? "non-interrupt" : "interrupt")));
+
+	spin_unlock((spinlock_t *)handle);
+
+	if (flags & ACPI_NOT_ISR)
+		ACPI_ENABLE_IRQS();
+
+	return_VOID;
+}
+
+
+acpi_status
+acpi_os_create_semaphore(
+	u32		max_units,
+	u32		initial_units,
+	acpi_handle	*handle)
+{
+	struct semaphore	*sem = NULL;
+
+	ACPI_FUNCTION_TRACE ("os_create_semaphore");
+
+	sem = acpi_os_allocate(sizeof(struct semaphore));
+	if (!sem)
+		return_ACPI_STATUS (AE_NO_MEMORY);
+	memset(sem, 0, sizeof(struct semaphore));
+
+	sema_init(sem, initial_units);
+
+	*handle = (acpi_handle*)sem;
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n", *handle, initial_units));
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+
+/*
+ * TODO: A better way to delete semaphores?  Linux doesn't have a
+ * 'delete_semaphore()' function -- may result in an invalid
+ * pointer dereference for non-synchronized consumers.	Should
+ * we at least check for blocked threads and signal/cancel them?
+ */
+
+acpi_status
+acpi_os_delete_semaphore(
+	acpi_handle	handle)
+{
+	struct semaphore *sem = (struct semaphore*) handle;
+
+	ACPI_FUNCTION_TRACE ("os_delete_semaphore");
+
+	if (!sem)
+		return_ACPI_STATUS (AE_BAD_PARAMETER);
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
+
+	acpi_os_free(sem); sem =  NULL;
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+
+/*
+ * TODO: The kernel doesn't have a 'down_timeout' function -- had to
+ * improvise.  The process is to sleep for one scheduler quantum
+ * until the semaphore becomes available.  Downside is that this
+ * may result in starvation for timeout-based waits when there's
+ * lots of semaphore activity.
+ *
+ * TODO: Support for units > 1?
+ */
+acpi_status
+acpi_os_wait_semaphore(
+	acpi_handle		handle,
+	u32			units,
+	u16			timeout)
+{
+	acpi_status		status = AE_OK;
+	struct semaphore	*sem = (struct semaphore*)handle;
+	int			ret = 0;
+
+	ACPI_FUNCTION_TRACE ("os_wait_semaphore");
+
+	if (!sem || (units < 1))
+		return_ACPI_STATUS (AE_BAD_PARAMETER);
+
+	if (units > 1)
+		return_ACPI_STATUS (AE_SUPPORT);
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n", handle, units, timeout));
+
+	if (in_interrupt())
+		timeout = 0;
+
+	switch (timeout)
+	{
+		/*
+		 * No Wait:
+		 * --------
+		 * A zero timeout value indicates that we shouldn't wait - just
+		 * acquire the semaphore if available otherwise return AE_TIME
+		 * (a.k.a. 'would block').
+		 */
+		case 0:
+		if(down_trylock(sem))
+			status = AE_TIME;
+		break;
+
+		/*
+		 * Wait Indefinitely:
+		 * ------------------
+		 */
+		case ACPI_WAIT_FOREVER:
+		down(sem);
+		break;
+
+		/*
+		 * Wait w/ Timeout:
+		 * ----------------
+		 */
+		default:
+		// TODO: A better timeout algorithm?
+		{
+			int i = 0;
+			static const int quantum_ms = 1000/HZ;
+
+			ret = down_trylock(sem);
+			for (i = timeout; (i > 0 && ret < 0); i -= quantum_ms) {
+				current->state = TASK_INTERRUPTIBLE;
+				schedule_timeout(1);
+				ret = down_trylock(sem);
+			}
+	
+			if (ret != 0)
+				status = AE_TIME;
+		}
+		break;
+	}
+
+	if (ACPI_FAILURE(status)) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Failed to acquire semaphore[%p|%d|%d], %s\n", 
+			handle, units, timeout, acpi_format_exception(status)));
+	}
+	else {
+		ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Acquired semaphore[%p|%d|%d]\n", handle, units, timeout));
+	}
+
+	return_ACPI_STATUS (status);
+}
+
+
+/*
+ * TODO: Support for units > 1?
+ */
+acpi_status
+acpi_os_signal_semaphore(
+    acpi_handle 	    handle,
+    u32 		    units)
+{
+	struct semaphore *sem = (struct semaphore *) handle;
+
+	ACPI_FUNCTION_TRACE ("os_signal_semaphore");
+
+	if (!sem || (units < 1))
+		return_ACPI_STATUS (AE_BAD_PARAMETER);
+
+	if (units > 1)
+		return_ACPI_STATUS (AE_SUPPORT);
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle, units));
+
+	up(sem);
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+u32
+acpi_os_get_line(char *buffer)
+{
+
+#ifdef ENABLE_DEBUGGER
+	if (acpi_in_debugger) {
+		u32 chars;
+
+		kdb_read(buffer, sizeof(line_buf));
+
+		/* remove the CR kdb includes */
+		chars = strlen(buffer) - 1;
+		buffer[chars] = '\0';
+	}
+#endif
+
+	return 0;
+}
+
+/*
+ * We just have to assume we're dealing with valid memory
+ */
+
+u8
+acpi_os_readable(void *ptr, acpi_size len)
+{
+	return 1;
+}
+
+u8
+acpi_os_writable(void *ptr, acpi_size len)
+{
+	return 1;
+}
+
+u32
+acpi_os_get_thread_id (void)
+{
+	if (!in_interrupt())
+		return current->pid;
+
+	return 0;
+}
+
+acpi_status
+acpi_os_signal (
+    u32		function,
+    void	*info)
+{
+	switch (function)
+	{
+	case ACPI_SIGNAL_FATAL:
+		printk(KERN_ERR PREFIX "Fatal opcode executed\n");
+		break;
+	case ACPI_SIGNAL_BREAKPOINT:
+		{
+			char *bp_info = (char*) info;
+
+			printk(KERN_ERR "ACPI breakpoint: %s\n", bp_info);
+		}
+	default:
+		break;
+	}
+
+	return AE_OK;
+}
+
+int __init
+acpi_os_name_setup(char *str)
+{
+	char *p = acpi_os_name;
+	int count = ACPI_MAX_OVERRIDE_LEN-1;
+
+	if (!str || !*str)
+		return 0;
+
+	for (; count-- && str && *str; str++) {
+		if (isalnum(*str) || *str == ' ' || *str == ':')
+			*p++ = *str;
+		else if (*str == '\'' || *str == '"')
+			continue;
+		else
+			break;
+	}
+	*p = 0;
+
+	return 1;
+		
+}
+
+__setup("acpi_os_name=", acpi_os_name_setup);
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)