Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 1 | /* |
| 2 | * File: htirq.c |
| 3 | * Purpose: Hypertransport Interrupt Capability |
| 4 | * |
| 5 | * Copyright (C) 2006 Linux Networx |
| 6 | * Copyright (C) Eric Biederman <ebiederman@lnxi.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/irq.h> |
| 10 | #include <linux/pci.h> |
| 11 | #include <linux/spinlock.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/gfp.h> |
Eric W. Biederman | 95d7788 | 2006-10-04 02:17:01 -0700 | [diff] [blame] | 14 | #include <linux/htirq.h> |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 15 | |
| 16 | /* Global ht irq lock. |
| 17 | * |
| 18 | * This is needed to serialize access to the data port in hypertransport |
| 19 | * irq capability. |
| 20 | * |
| 21 | * With multiple simultaneous hypertransport irq devices it might pay |
| 22 | * to make this more fine grained. But start with simple, stupid, and correct. |
| 23 | */ |
| 24 | static DEFINE_SPINLOCK(ht_irq_lock); |
| 25 | |
| 26 | struct ht_irq_cfg { |
| 27 | struct pci_dev *dev; |
| 28 | unsigned pos; |
| 29 | unsigned idx; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 30 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 31 | }; |
| 32 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 33 | |
| 34 | void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg) |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 35 | { |
| 36 | struct ht_irq_cfg *cfg = get_irq_data(irq); |
| 37 | unsigned long flags; |
| 38 | spin_lock_irqsave(&ht_irq_lock, flags); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 39 | if (cfg->msg.address_lo != msg->address_lo) { |
| 40 | pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx); |
| 41 | pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo); |
| 42 | } |
| 43 | if (cfg->msg.address_hi != msg->address_hi) { |
| 44 | pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1); |
| 45 | pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi); |
| 46 | } |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 47 | spin_unlock_irqrestore(&ht_irq_lock, flags); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 48 | cfg->msg = *msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 49 | } |
| 50 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 51 | void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg) |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 52 | { |
| 53 | struct ht_irq_cfg *cfg = get_irq_data(irq); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 54 | *msg = cfg->msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | void mask_ht_irq(unsigned int irq) |
| 58 | { |
| 59 | struct ht_irq_cfg *cfg; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 60 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 61 | |
| 62 | cfg = get_irq_data(irq); |
| 63 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 64 | msg = cfg->msg; |
| 65 | msg.address_lo |= 1; |
| 66 | write_ht_irq_msg(irq, &msg); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 67 | } |
| 68 | |
| 69 | void unmask_ht_irq(unsigned int irq) |
| 70 | { |
| 71 | struct ht_irq_cfg *cfg; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 72 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 73 | |
| 74 | cfg = get_irq_data(irq); |
| 75 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 76 | msg = cfg->msg; |
| 77 | msg.address_lo &= ~1; |
| 78 | write_ht_irq_msg(irq, &msg); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 79 | } |
| 80 | |
| 81 | /** |
| 82 | * ht_create_irq - create an irq and attach it to a device. |
| 83 | * @dev: The hypertransport device to find the irq capability on. |
| 84 | * @idx: Which of the possible irqs to attach to. |
| 85 | * |
| 86 | * ht_create_irq is needs to be called for all hypertransport devices |
| 87 | * that generate irqs. |
| 88 | * |
| 89 | * The irq number of the new irq or a negative error value is returned. |
| 90 | */ |
| 91 | int ht_create_irq(struct pci_dev *dev, int idx) |
| 92 | { |
| 93 | struct ht_irq_cfg *cfg; |
| 94 | unsigned long flags; |
| 95 | u32 data; |
| 96 | int max_irq; |
| 97 | int pos; |
| 98 | int irq; |
| 99 | |
| 100 | pos = pci_find_capability(dev, PCI_CAP_ID_HT); |
| 101 | while (pos) { |
| 102 | u8 subtype; |
| 103 | pci_read_config_byte(dev, pos + 3, &subtype); |
| 104 | if (subtype == HT_CAPTYPE_IRQ) |
| 105 | break; |
| 106 | pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_HT); |
| 107 | } |
| 108 | if (!pos) |
| 109 | return -EINVAL; |
| 110 | |
| 111 | /* Verify the idx I want to use is in range */ |
| 112 | spin_lock_irqsave(&ht_irq_lock, flags); |
| 113 | pci_write_config_byte(dev, pos + 2, 1); |
| 114 | pci_read_config_dword(dev, pos + 4, &data); |
| 115 | spin_unlock_irqrestore(&ht_irq_lock, flags); |
| 116 | |
| 117 | max_irq = (data >> 16) & 0xff; |
| 118 | if ( idx > max_irq) |
| 119 | return -EINVAL; |
| 120 | |
| 121 | cfg = kmalloc(sizeof(*cfg), GFP_KERNEL); |
| 122 | if (!cfg) |
| 123 | return -ENOMEM; |
| 124 | |
| 125 | cfg->dev = dev; |
| 126 | cfg->pos = pos; |
| 127 | cfg->idx = 0x10 + (idx * 2); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame^] | 128 | /* Initialize msg to a value that will never match the first write. */ |
| 129 | cfg->msg.address_lo = 0xffffffff; |
| 130 | cfg->msg.address_hi = 0xffffffff; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 131 | |
| 132 | irq = create_irq(); |
| 133 | if (irq < 0) { |
| 134 | kfree(cfg); |
| 135 | return -EBUSY; |
| 136 | } |
| 137 | set_irq_data(irq, cfg); |
| 138 | |
| 139 | if (arch_setup_ht_irq(irq, dev) < 0) { |
| 140 | ht_destroy_irq(irq); |
| 141 | return -EBUSY; |
| 142 | } |
| 143 | |
| 144 | return irq; |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * ht_destroy_irq - destroy an irq created with ht_create_irq |
| 149 | * |
| 150 | * This reverses ht_create_irq removing the specified irq from |
| 151 | * existence. The irq should be free before this happens. |
| 152 | */ |
| 153 | void ht_destroy_irq(unsigned int irq) |
| 154 | { |
| 155 | struct ht_irq_cfg *cfg; |
| 156 | |
| 157 | cfg = get_irq_data(irq); |
| 158 | set_irq_chip(irq, NULL); |
| 159 | set_irq_data(irq, NULL); |
| 160 | destroy_irq(irq); |
| 161 | |
| 162 | kfree(cfg); |
| 163 | } |
| 164 | |
| 165 | EXPORT_SYMBOL(ht_create_irq); |
| 166 | EXPORT_SYMBOL(ht_destroy_irq); |