projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 9a4da8a5 JG |
1 | /* |
| 2 | * Copyright IBM Corp. 2012 | |
| 3 | * | |
| 4 | * Author(s): | |
| 5 | * Jan Glauber <jang@linux.vnet.ibm.com> | |
| 6 | */ | |
| 7 | ||
| 8 | #define COMPONENT "zPCI" | |
| 9 | #define pr_fmt(fmt) COMPONENT ": " fmt | |
| 10 | ||
| 11 | #include <linux/kernel.h> | |
| 12 | #include <linux/err.h> | |
| 13 | #include <linux/rculist.h> | |
| 14 | #include <linux/hash.h> | |
| 15 | #include <linux/pci.h> | |
| 16 | #include <linux/msi.h> | |
| 17 | #include <asm/hw_irq.h> | |
| 18 | ||
| 19 | /* mapping of irq numbers to msi_desc */ | |
| 20 | static struct hlist_head *msi_hash; | |
| 21 | static unsigned int msihash_shift = 6; | |
| 22 | #define msi_hashfn(nr) hash_long(nr, msihash_shift) | |
| 23 | ||
| 24 | static DEFINE_SPINLOCK(msi_map_lock); | |
| 25 | ||
| 26 | struct msi_desc *__irq_get_msi_desc(unsigned int irq) | |
| 27 | { | |
| 28 | struct hlist_node *entry; | |
| 29 | struct msi_map *map; | |
| 30 | ||
| 31 | hlist_for_each_entry_rcu(map, entry, | |
| 32 | &msi_hash[msi_hashfn(irq)], msi_chain) | |
| 33 | if (map->irq == irq) | |
| 34 | return map->msi; | |
| 35 | return NULL; | |
| 36 | } | |
| 37 | ||
| 38 | int zpci_msi_set_mask_bits(struct msi_desc *msi, u32 mask, u32 flag) | |
| 39 | { | |
| 40 | if (msi->msi_attrib.is_msix) { | |
| 41 | int offset = msi->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + | |
| 42 | PCI_MSIX_ENTRY_VECTOR_CTRL; | |
| 43 | msi->masked = readl(msi->mask_base + offset); | |
| 44 | writel(flag, msi->mask_base + offset); | |
| 45 | } else { | |
| 46 | if (msi->msi_attrib.maskbit) { | |
| 47 | int pos; | |
| 48 | u32 mask_bits; | |
| 49 | ||
| 50 | pos = (long) msi->mask_base; | |
| 51 | pci_read_config_dword(msi->dev, pos, &mask_bits); | |
| 52 | mask_bits &= ~(mask); | |
| 53 | mask_bits |= flag & mask; | |
| 54 | pci_write_config_dword(msi->dev, pos, mask_bits); | |
| 55 | } else { | |
| 56 | return 0; | |
| 57 | } | |
| 58 | } | |
| 59 | ||
| 60 | msi->msi_attrib.maskbit = !!flag; | |
| 61 | return 1; | |
| 62 | } | |
| 63 | ||
| 64 | int zpci_setup_msi_irq(struct zpci_dev *zdev, struct msi_desc *msi, | |
| 65 | unsigned int nr, int offset) | |
| 66 | { | |
| 67 | struct msi_map *map; | |
| 68 | struct msi_msg msg; | |
| 69 | int rc; | |
| 70 | ||
| 71 | map = kmalloc(sizeof(*map), GFP_KERNEL); | |
| 72 | if (map == NULL) | |
| 73 | return -ENOMEM; | |
| 74 | ||
| 75 | map->irq = nr; | |
| 76 | map->msi = msi; | |
| 77 | zdev->msi_map[nr & ZPCI_MSI_MASK] = map; | |
| 78 | ||
| 79 | pr_debug("%s hashing irq: %u to bucket nr: %llu\n", | |
| 80 | __func__, nr, msi_hashfn(nr)); | |
| 81 | hlist_add_head_rcu(&map->msi_chain, &msi_hash[msi_hashfn(nr)]); | |
| 82 | ||
| 83 | spin_lock(&msi_map_lock); | |
| 84 | rc = irq_set_msi_desc(nr, msi); | |
| 85 | if (rc) { | |
| 86 | spin_unlock(&msi_map_lock); | |
| 87 | hlist_del_rcu(&map->msi_chain); | |
| 88 | kfree(map); | |
| 89 | zdev->msi_map[nr & ZPCI_MSI_MASK] = NULL; | |
| 90 | return rc; | |
| 91 | } | |
| 92 | spin_unlock(&msi_map_lock); | |
| 93 | ||
| 94 | msg.data = nr - offset; | |
| 95 | msg.address_lo = zdev->msi_addr & 0xffffffff; | |
| 96 | msg.address_hi = zdev->msi_addr >> 32; | |
| 97 | write_msi_msg(nr, &msg); | |
| 98 | return 0; | |
| 99 | } | |
| 100 | ||
| 101 | void zpci_teardown_msi_irq(struct zpci_dev *zdev, struct msi_desc *msi) | |
| 102 | { | |
| 103 | int irq = msi->irq & ZPCI_MSI_MASK; | |
| 104 | struct msi_map *map; | |
| 105 | ||
| 106 | msi->msg.address_lo = 0; | |
| 107 | msi->msg.address_hi = 0; | |
| 108 | msi->msg.data = 0; | |
| 109 | msi->irq = 0; | |
| 110 | zpci_msi_set_mask_bits(msi, 1, 1); | |
| 111 | ||
| 112 | spin_lock(&msi_map_lock); | |
| 113 | map = zdev->msi_map[irq]; | |
| 114 | hlist_del_rcu(&map->msi_chain); | |
| 115 | kfree(map); | |
| 116 | zdev->msi_map[irq] = NULL; | |
| 117 | spin_unlock(&msi_map_lock); | |
| 118 | } | |
| 119 | ||
| 120 | /* | |
| 121 | * The msi hash table has 256 entries which is good for 4..20 | |
| 122 | * devices (a typical device allocates 10 + CPUs MSI's). Maybe make | |
| 123 | * the hash table size adjustable later. | |
| 124 | */ | |
| 125 | int __init zpci_msihash_init(void) | |
| 126 | { | |
| 127 | unsigned int i; | |
| 128 | ||
| 129 | msi_hash = kmalloc(256 * sizeof(*msi_hash), GFP_KERNEL); | |
| 130 | if (!msi_hash) | |
| 131 | return -ENOMEM; | |
| 132 | ||
| 133 | for (i = 0; i < (1U << msihash_shift); i++) | |
| 134 | INIT_HLIST_HEAD(&msi_hash[i]); | |
| 135 | return 0; | |
| 136 | } | |
| 137 | ||
| 138 | void __init zpci_msihash_exit(void) | |
| 139 | { | |
| 140 | kfree(msi_hash); | |
| 141 | } |