/* * Copyright 2006-2008, Michael Ellerman, IBM Corporation. * * 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; version 2 of the * License. * */ #include <linux/slab.h>#include <linux/kernel.h>#include <linux/bitmap.h>#include <asm/msi_bitmap.h> int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int num){	unsigned long flags;	int offset, order = get_count_order(num); 	spin_lock_irqsave(&bmp->lock, flags);	/*	 * This is fast, but stricter than we need. We might want to add	 * a fallback routine which does a linear search with no alignment.	 */	offset = bitmap_find_free_region(bmp->bitmap, bmp->irq_count, order);	spin_unlock_irqrestore(&bmp->lock, flags); 	pr_debug("msi_bitmap: allocated 0x%x (2^%d) at offset 0x%x\n",		 num, order, offset); 	return offset;} void msi_bitmap_free_hwirqs(struct msi_bitmap *bmp, unsigned int offset,			    unsigned int num){	unsigned long flags;	int order = get_count_order(num); 	pr_debug("msi_bitmap: freeing 0x%x (2^%d) at offset 0x%x\n",		 num, order, offset); 	spin_lock_irqsave(&bmp->lock, flags);	bitmap_release_region(bmp->bitmap, offset, order);	spin_unlock_irqrestore(&bmp->lock, flags);} void msi_bitmap_reserve_hwirq(struct msi_bitmap *bmp, unsigned int hwirq){	unsigned long flags; 	pr_debug("msi_bitmap: reserving hwirq 0x%x\n", hwirq); 	spin_lock_irqsave(&bmp->lock, flags);	bitmap_allocate_region(bmp->bitmap, hwirq, 0);	spin_unlock_irqrestore(&bmp->lock, flags);} /** * msi_bitmap_reserve_dt_hwirqs - Reserve irqs specified in the device tree. * @bmp: pointer to the MSI bitmap. * * Looks in the device tree to see if there is a property specifying which * irqs can be used for MSI. If found those irqs reserved in the device tree * are reserved in the bitmap. * * Returns 0 for success, < 0 if there was an error, and > 0 if no property * was found in the device tree. **/int msi_bitmap_reserve_dt_hwirqs(struct msi_bitmap *bmp){	int i, j, len;	const u32 *p; 	if (!bmp->of_node)		return 1; 	p = of_get_property(bmp->of_node, "msi-available-ranges", &len);	if (!p) {		pr_debug("msi_bitmap: no msi-available-ranges property " \			 "found on %s\n", bmp->of_node->full_name);		return 1;	} 	if (len % (2 * sizeof(u32)) != 0) {		printk(KERN_WARNING "msi_bitmap: Malformed msi-available-ranges"		       " property on %s\n", bmp->of_node->full_name);		return -EINVAL;	} 	bitmap_allocate_region(bmp->bitmap, 0, get_count_order(bmp->irq_count)); 	spin_lock(&bmp->lock); 	/* Format is: (<u32 start> <u32 count>)+ */	len /= 2 * sizeof(u32);	for (i = 0; i < len; i++, p += 2) {		for (j = 0; j < *(p + 1); j++)			bitmap_release_region(bmp->bitmap, *p + j, 0);	} 	spin_unlock(&bmp->lock); 	return 0;} int msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count,		     struct device_node *of_node){	int size; 	if (!irq_count)		return -EINVAL; 	size = BITS_TO_LONGS(irq_count) * sizeof(long);	pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size); 	bmp->bitmap = zalloc_maybe_bootmem(size, GFP_KERNEL);	if (!bmp->bitmap) {		pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n");		return -ENOMEM;	} 	/* We zalloc'ed the bitmap, so all irqs are free by default */	spin_lock_init(&bmp->lock);	bmp->of_node = of_node_get(of_node);	bmp->irq_count = irq_count; 	return 0;} void msi_bitmap_free(struct msi_bitmap *bmp){	/* we can't free the bitmap we don't know if it's bootmem etc. */	of_node_put(bmp->of_node);	bmp->bitmap = NULL;} #ifdef CONFIG_MSI_BITMAP_SELFTEST #define check(x)	\	if (!(x)) printk("msi_bitmap: test failed at line %d\n", __LINE__); void __init test_basics(void){	struct msi_bitmap bmp;	int i, size = 512; 	/* Can't allocate a bitmap of 0 irqs */	check(msi_bitmap_alloc(&bmp, 0, NULL) != 0); 	/* of_node may be NULL */	check(0 == msi_bitmap_alloc(&bmp, size, NULL)); 	/* Should all be free by default */	check(0 == bitmap_find_free_region(bmp.bitmap, size,					   get_count_order(size)));	bitmap_release_region(bmp.bitmap, 0, get_count_order(size)); 	/* With no node, there's no msi-available-ranges, so expect > 0 */	check(msi_bitmap_reserve_dt_hwirqs(&bmp) > 0); 	/* Should all still be free */	check(0 == bitmap_find_free_region(bmp.bitmap, size,					   get_count_order(size)));	bitmap_release_region(bmp.bitmap, 0, get_count_order(size)); 	/* Check we can fill it up and then no more */	for (i = 0; i < size; i++)		check(msi_bitmap_alloc_hwirqs(&bmp, 1) >= 0); 	check(msi_bitmap_alloc_hwirqs(&bmp, 1) < 0); 	/* Should all be allocated */	check(bitmap_find_free_region(bmp.bitmap, size, 0) < 0); 	/* And if we free one we can then allocate another */	msi_bitmap_free_hwirqs(&bmp, size / 2, 1);	check(msi_bitmap_alloc_hwirqs(&bmp, 1) == size / 2); 	msi_bitmap_free(&bmp); 	/* Clients may check bitmap == NULL for "not-allocated" */	check(bmp.bitmap == NULL); 	kfree(bmp.bitmap);} void __init test_of_node(void){	u32 prop_data[] = { 10, 10, 25, 3, 40, 1, 100, 100, 200, 20 };	const char *expected_str = "0-9,20-24,28-39,41-99,220-255";	char *prop_name = "msi-available-ranges";	char *node_name = "/fakenode";	struct device_node of_node;	struct property prop;	struct msi_bitmap bmp;	int size = 256;	DECLARE_BITMAP(expected, size); 	/* There should really be a struct device_node allocator */	memset(&of_node, 0, sizeof(of_node));	kref_init(&of_node.kref);	of_node.full_name = node_name; 	check(0 == msi_bitmap_alloc(&bmp, size, &of_node)); 	/* No msi-available-ranges, so expect > 0 */	check(msi_bitmap_reserve_dt_hwirqs(&bmp) > 0); 	/* Should all still be free */	check(0 == bitmap_find_free_region(bmp.bitmap, size,					   get_count_order(size)));	bitmap_release_region(bmp.bitmap, 0, get_count_order(size)); 	/* Now create a fake msi-available-ranges property */ 	/* There should really .. oh whatever */	memset(&prop, 0, sizeof(prop));	prop.name = prop_name;	prop.value = &prop_data;	prop.length = sizeof(prop_data); 	of_node.properties = &prop; 	/* msi-available-ranges, so expect == 0 */	check(msi_bitmap_reserve_dt_hwirqs(&bmp) == 0); 	/* Check we got the expected result */	check(0 == bitmap_parselist(expected_str, expected, size));	check(bitmap_equal(expected, bmp.bitmap, size)); 	msi_bitmap_free(&bmp);	kfree(bmp.bitmap);} int __init msi_bitmap_selftest(void){	printk(KERN_DEBUG "Running MSI bitmap self-tests ...\n"); 	test_basics();	test_of_node(); 	return 0;}late_initcall(msi_bitmap_selftest);#endif /* CONFIG_MSI_BITMAP_SELFTEST */