17e302869SMichael Ellerman /* 27e302869SMichael Ellerman * Copyright 2006-2008, Michael Ellerman, IBM Corporation. 37e302869SMichael Ellerman * 47e302869SMichael Ellerman * This program is free software; you can redistribute it and/or 57e302869SMichael Ellerman * modify it under the terms of the GNU General Public License 67e302869SMichael Ellerman * as published by the Free Software Foundation; version 2 of the 77e302869SMichael Ellerman * License. 87e302869SMichael Ellerman * 97e302869SMichael Ellerman */ 107e302869SMichael Ellerman 115a0e3ad6STejun Heo #include <linux/slab.h> 127e302869SMichael Ellerman #include <linux/kernel.h> 13514c6032SRandy Dunlap #include <linux/kmemleak.h> 147e302869SMichael Ellerman #include <linux/bitmap.h> 1557c8a661SMike Rapoport #include <linux/memblock.h> 167e302869SMichael Ellerman #include <asm/msi_bitmap.h> 17ae3a197eSDavid Howells #include <asm/setup.h> 187e302869SMichael Ellerman 197e302869SMichael Ellerman int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int num) 207e302869SMichael Ellerman { 217e302869SMichael Ellerman unsigned long flags; 227e302869SMichael Ellerman int offset, order = get_count_order(num); 237e302869SMichael Ellerman 247e302869SMichael Ellerman spin_lock_irqsave(&bmp->lock, flags); 25b0345bbcSIan Munsie 26b0345bbcSIan Munsie offset = bitmap_find_next_zero_area(bmp->bitmap, bmp->irq_count, 0, 27b0345bbcSIan Munsie num, (1 << order) - 1); 28b0345bbcSIan Munsie if (offset > bmp->irq_count) 29b0345bbcSIan Munsie goto err; 30b0345bbcSIan Munsie 31b0345bbcSIan Munsie bitmap_set(bmp->bitmap, offset, num); 327e302869SMichael Ellerman spin_unlock_irqrestore(&bmp->lock, flags); 337e302869SMichael Ellerman 34b0345bbcSIan Munsie pr_debug("msi_bitmap: allocated 0x%x at offset 0x%x\n", num, offset); 357e302869SMichael Ellerman 367e302869SMichael Ellerman return offset; 37b0345bbcSIan Munsie err: 38b0345bbcSIan Munsie spin_unlock_irqrestore(&bmp->lock, flags); 39b0345bbcSIan Munsie return -ENOMEM; 407e302869SMichael Ellerman } 41b0345bbcSIan Munsie EXPORT_SYMBOL(msi_bitmap_alloc_hwirqs); 427e302869SMichael Ellerman 437e302869SMichael Ellerman void msi_bitmap_free_hwirqs(struct msi_bitmap *bmp, unsigned int offset, 447e302869SMichael Ellerman unsigned int num) 457e302869SMichael Ellerman { 467e302869SMichael Ellerman unsigned long flags; 477e302869SMichael Ellerman 48b0345bbcSIan Munsie pr_debug("msi_bitmap: freeing 0x%x at offset 0x%x\n", 49b0345bbcSIan Munsie num, offset); 507e302869SMichael Ellerman 517e302869SMichael Ellerman spin_lock_irqsave(&bmp->lock, flags); 52b0345bbcSIan Munsie bitmap_clear(bmp->bitmap, offset, num); 537e302869SMichael Ellerman spin_unlock_irqrestore(&bmp->lock, flags); 547e302869SMichael Ellerman } 55b0345bbcSIan Munsie EXPORT_SYMBOL(msi_bitmap_free_hwirqs); 567e302869SMichael Ellerman 577e302869SMichael Ellerman void msi_bitmap_reserve_hwirq(struct msi_bitmap *bmp, unsigned int hwirq) 587e302869SMichael Ellerman { 597e302869SMichael Ellerman unsigned long flags; 607e302869SMichael Ellerman 617e302869SMichael Ellerman pr_debug("msi_bitmap: reserving hwirq 0x%x\n", hwirq); 627e302869SMichael Ellerman 637e302869SMichael Ellerman spin_lock_irqsave(&bmp->lock, flags); 647e302869SMichael Ellerman bitmap_allocate_region(bmp->bitmap, hwirq, 0); 657e302869SMichael Ellerman spin_unlock_irqrestore(&bmp->lock, flags); 667e302869SMichael Ellerman } 677e302869SMichael Ellerman 687e302869SMichael Ellerman /** 697e302869SMichael Ellerman * msi_bitmap_reserve_dt_hwirqs - Reserve irqs specified in the device tree. 707e302869SMichael Ellerman * @bmp: pointer to the MSI bitmap. 717e302869SMichael Ellerman * 727e302869SMichael Ellerman * Looks in the device tree to see if there is a property specifying which 737e302869SMichael Ellerman * irqs can be used for MSI. If found those irqs reserved in the device tree 747e302869SMichael Ellerman * are reserved in the bitmap. 757e302869SMichael Ellerman * 767e302869SMichael Ellerman * Returns 0 for success, < 0 if there was an error, and > 0 if no property 777e302869SMichael Ellerman * was found in the device tree. 787e302869SMichael Ellerman **/ 797e302869SMichael Ellerman int msi_bitmap_reserve_dt_hwirqs(struct msi_bitmap *bmp) 807e302869SMichael Ellerman { 817e302869SMichael Ellerman int i, j, len; 827e302869SMichael Ellerman const u32 *p; 837e302869SMichael Ellerman 847e302869SMichael Ellerman if (!bmp->of_node) 857e302869SMichael Ellerman return 1; 867e302869SMichael Ellerman 877e302869SMichael Ellerman p = of_get_property(bmp->of_node, "msi-available-ranges", &len); 887e302869SMichael Ellerman if (!p) { 897e302869SMichael Ellerman pr_debug("msi_bitmap: no msi-available-ranges property " \ 90b7c670d6SRob Herring "found on %pOF\n", bmp->of_node); 917e302869SMichael Ellerman return 1; 927e302869SMichael Ellerman } 937e302869SMichael Ellerman 947e302869SMichael Ellerman if (len % (2 * sizeof(u32)) != 0) { 957e302869SMichael Ellerman printk(KERN_WARNING "msi_bitmap: Malformed msi-available-ranges" 96b7c670d6SRob Herring " property on %pOF\n", bmp->of_node); 977e302869SMichael Ellerman return -EINVAL; 987e302869SMichael Ellerman } 997e302869SMichael Ellerman 1007e302869SMichael Ellerman bitmap_allocate_region(bmp->bitmap, 0, get_count_order(bmp->irq_count)); 1017e302869SMichael Ellerman 1027e302869SMichael Ellerman spin_lock(&bmp->lock); 1037e302869SMichael Ellerman 1047e302869SMichael Ellerman /* Format is: (<u32 start> <u32 count>)+ */ 1057e302869SMichael Ellerman len /= 2 * sizeof(u32); 1067e302869SMichael Ellerman for (i = 0; i < len; i++, p += 2) { 1077e302869SMichael Ellerman for (j = 0; j < *(p + 1); j++) 1087e302869SMichael Ellerman bitmap_release_region(bmp->bitmap, *p + j, 0); 1097e302869SMichael Ellerman } 1107e302869SMichael Ellerman 1117e302869SMichael Ellerman spin_unlock(&bmp->lock); 1127e302869SMichael Ellerman 1137e302869SMichael Ellerman return 0; 1147e302869SMichael Ellerman } 1157e302869SMichael Ellerman 116bd721ea7SFabian Frederick int __ref msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count, 1177e302869SMichael Ellerman struct device_node *of_node) 1187e302869SMichael Ellerman { 1197e302869SMichael Ellerman int size; 1207e302869SMichael Ellerman 1217e302869SMichael Ellerman if (!irq_count) 1227e302869SMichael Ellerman return -EINVAL; 1237e302869SMichael Ellerman 1247e302869SMichael Ellerman size = BITS_TO_LONGS(irq_count) * sizeof(long); 1257e302869SMichael Ellerman pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size); 1267e302869SMichael Ellerman 127cb2d3883SDenis Kirjanov bmp->bitmap_from_slab = slab_is_available(); 128cb2d3883SDenis Kirjanov if (bmp->bitmap_from_slab) 129cb2d3883SDenis Kirjanov bmp->bitmap = kzalloc(size, GFP_KERNEL); 130cb2d3883SDenis Kirjanov else { 1317e1c4e27SMike Rapoport bmp->bitmap = memblock_alloc(size, SMP_CACHE_BYTES); 132cb2d3883SDenis Kirjanov /* the bitmap won't be freed from memblock allocator */ 133cb2d3883SDenis Kirjanov kmemleak_not_leak(bmp->bitmap); 134cb2d3883SDenis Kirjanov } 135cb2d3883SDenis Kirjanov 1367e302869SMichael Ellerman if (!bmp->bitmap) { 1377e302869SMichael Ellerman pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n"); 1387e302869SMichael Ellerman return -ENOMEM; 1397e302869SMichael Ellerman } 1407e302869SMichael Ellerman 1417e302869SMichael Ellerman /* We zalloc'ed the bitmap, so all irqs are free by default */ 1427e302869SMichael Ellerman spin_lock_init(&bmp->lock); 1437e302869SMichael Ellerman bmp->of_node = of_node_get(of_node); 1447e302869SMichael Ellerman bmp->irq_count = irq_count; 1457e302869SMichael Ellerman 1467e302869SMichael Ellerman return 0; 1477e302869SMichael Ellerman } 1487e302869SMichael Ellerman 1497e302869SMichael Ellerman void msi_bitmap_free(struct msi_bitmap *bmp) 1507e302869SMichael Ellerman { 151cb2d3883SDenis Kirjanov if (bmp->bitmap_from_slab) 152cb2d3883SDenis Kirjanov kfree(bmp->bitmap); 1537e302869SMichael Ellerman of_node_put(bmp->of_node); 1547e302869SMichael Ellerman bmp->bitmap = NULL; 1557e302869SMichael Ellerman } 1567e302869SMichael Ellerman 1577e302869SMichael Ellerman #ifdef CONFIG_MSI_BITMAP_SELFTEST 1587e302869SMichael Ellerman 159e51df2c1SAnton Blanchard static void __init test_basics(void) 1607e302869SMichael Ellerman { 1617e302869SMichael Ellerman struct msi_bitmap bmp; 162695911fbSMichael Ellerman int rc, i, size = 512; 1637e302869SMichael Ellerman 1647e302869SMichael Ellerman /* Can't allocate a bitmap of 0 irqs */ 1654a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_alloc(&bmp, 0, NULL) == 0); 1667e302869SMichael Ellerman 1677e302869SMichael Ellerman /* of_node may be NULL */ 1684a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_alloc(&bmp, size, NULL)); 1697e302869SMichael Ellerman 1707e302869SMichael Ellerman /* Should all be free by default */ 1714a77f2bdSMichael Ellerman WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size))); 1727e302869SMichael Ellerman bitmap_release_region(bmp.bitmap, 0, get_count_order(size)); 1737e302869SMichael Ellerman 1747e302869SMichael Ellerman /* With no node, there's no msi-available-ranges, so expect > 0 */ 1754a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0); 1767e302869SMichael Ellerman 1777e302869SMichael Ellerman /* Should all still be free */ 1784a77f2bdSMichael Ellerman WARN_ON(bitmap_find_free_region(bmp.bitmap, size, get_count_order(size))); 1797e302869SMichael Ellerman bitmap_release_region(bmp.bitmap, 0, get_count_order(size)); 1807e302869SMichael Ellerman 1817e302869SMichael Ellerman /* Check we can fill it up and then no more */ 1827e302869SMichael Ellerman for (i = 0; i < size; i++) 1834a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) < 0); 1847e302869SMichael Ellerman 1854a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) >= 0); 1867e302869SMichael Ellerman 1877e302869SMichael Ellerman /* Should all be allocated */ 1884a77f2bdSMichael Ellerman WARN_ON(bitmap_find_free_region(bmp.bitmap, size, 0) >= 0); 1897e302869SMichael Ellerman 1907e302869SMichael Ellerman /* And if we free one we can then allocate another */ 1917e302869SMichael Ellerman msi_bitmap_free_hwirqs(&bmp, size / 2, 1); 1924a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_alloc_hwirqs(&bmp, 1) != size / 2); 1937e302869SMichael Ellerman 194695911fbSMichael Ellerman /* Free most of them for the alignment tests */ 195695911fbSMichael Ellerman msi_bitmap_free_hwirqs(&bmp, 3, size - 3); 196695911fbSMichael Ellerman 197b0345bbcSIan Munsie /* Check we get a naturally aligned offset */ 198695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 2); 1994a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 2 != 0); 200695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 4); 2014a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 4 != 0); 202695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 8); 2034a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 8 != 0); 204695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 9); 2054a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 16 != 0); 206695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 3); 2074a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 4 != 0); 208695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 7); 2094a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 8 != 0); 210695911fbSMichael Ellerman rc = msi_bitmap_alloc_hwirqs(&bmp, 121); 2114a77f2bdSMichael Ellerman WARN_ON(rc < 0 && rc % 128 != 0); 212b0345bbcSIan Munsie 2137e302869SMichael Ellerman msi_bitmap_free(&bmp); 2147e302869SMichael Ellerman 2154a77f2bdSMichael Ellerman /* Clients may WARN_ON bitmap == NULL for "not-allocated" */ 2164a77f2bdSMichael Ellerman WARN_ON(bmp.bitmap != NULL); 2177e302869SMichael Ellerman } 2187e302869SMichael Ellerman 219e51df2c1SAnton Blanchard static void __init test_of_node(void) 2207e302869SMichael Ellerman { 2217e302869SMichael Ellerman u32 prop_data[] = { 10, 10, 25, 3, 40, 1, 100, 100, 200, 20 }; 2227e302869SMichael Ellerman const char *expected_str = "0-9,20-24,28-39,41-99,220-255"; 2237e302869SMichael Ellerman char *prop_name = "msi-available-ranges"; 2247e302869SMichael Ellerman char *node_name = "/fakenode"; 2257e302869SMichael Ellerman struct device_node of_node; 2267e302869SMichael Ellerman struct property prop; 2277e302869SMichael Ellerman struct msi_bitmap bmp; 2281b80ac64SKees Cook #define SIZE_EXPECTED 256 2291b80ac64SKees Cook DECLARE_BITMAP(expected, SIZE_EXPECTED); 2307e302869SMichael Ellerman 2317e302869SMichael Ellerman /* There should really be a struct device_node allocator */ 2327e302869SMichael Ellerman memset(&of_node, 0, sizeof(of_node)); 233e47ff70aSLi Zhong of_node_init(&of_node); 2347e302869SMichael Ellerman of_node.full_name = node_name; 2357e302869SMichael Ellerman 2361b80ac64SKees Cook WARN_ON(msi_bitmap_alloc(&bmp, SIZE_EXPECTED, &of_node)); 2377e302869SMichael Ellerman 2387e302869SMichael Ellerman /* No msi-available-ranges, so expect > 0 */ 2394a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp) <= 0); 2407e302869SMichael Ellerman 2417e302869SMichael Ellerman /* Should all still be free */ 2421b80ac64SKees Cook WARN_ON(bitmap_find_free_region(bmp.bitmap, SIZE_EXPECTED, 2431b80ac64SKees Cook get_count_order(SIZE_EXPECTED))); 2441b80ac64SKees Cook bitmap_release_region(bmp.bitmap, 0, get_count_order(SIZE_EXPECTED)); 2457e302869SMichael Ellerman 2467e302869SMichael Ellerman /* Now create a fake msi-available-ranges property */ 2477e302869SMichael Ellerman 2487e302869SMichael Ellerman /* There should really .. oh whatever */ 2497e302869SMichael Ellerman memset(&prop, 0, sizeof(prop)); 2507e302869SMichael Ellerman prop.name = prop_name; 2517e302869SMichael Ellerman prop.value = &prop_data; 2527e302869SMichael Ellerman prop.length = sizeof(prop_data); 2537e302869SMichael Ellerman 2547e302869SMichael Ellerman of_node.properties = ∝ 2557e302869SMichael Ellerman 2567e302869SMichael Ellerman /* msi-available-ranges, so expect == 0 */ 2574a77f2bdSMichael Ellerman WARN_ON(msi_bitmap_reserve_dt_hwirqs(&bmp)); 2587e302869SMichael Ellerman 2597e302869SMichael Ellerman /* Check we got the expected result */ 2601b80ac64SKees Cook WARN_ON(bitmap_parselist(expected_str, expected, SIZE_EXPECTED)); 2611b80ac64SKees Cook WARN_ON(!bitmap_equal(expected, bmp.bitmap, SIZE_EXPECTED)); 2627e302869SMichael Ellerman 2637e302869SMichael Ellerman msi_bitmap_free(&bmp); 2647e302869SMichael Ellerman kfree(bmp.bitmap); 2657e302869SMichael Ellerman } 2667e302869SMichael Ellerman 267e51df2c1SAnton Blanchard static int __init msi_bitmap_selftest(void) 2687e302869SMichael Ellerman { 2697e302869SMichael Ellerman printk(KERN_DEBUG "Running MSI bitmap self-tests ...\n"); 2707e302869SMichael Ellerman 2717e302869SMichael Ellerman test_basics(); 2727e302869SMichael Ellerman test_of_node(); 2737e302869SMichael Ellerman 2747e302869SMichael Ellerman return 0; 2757e302869SMichael Ellerman } 2767e302869SMichael Ellerman late_initcall(msi_bitmap_selftest); 2777e302869SMichael Ellerman #endif /* CONFIG_MSI_BITMAP_SELFTEST */ 278