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; |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 28 | /* Update callback used to cope with buggy hardware */ |
| 29 | ht_irq_update_t *update; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 30 | unsigned pos; |
| 31 | unsigned idx; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 32 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 33 | }; |
| 34 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 35 | |
| 36 | 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] | 37 | { |
| 38 | struct ht_irq_cfg *cfg = get_irq_data(irq); |
| 39 | unsigned long flags; |
| 40 | spin_lock_irqsave(&ht_irq_lock, flags); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 41 | if (cfg->msg.address_lo != msg->address_lo) { |
| 42 | pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx); |
| 43 | pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo); |
| 44 | } |
| 45 | if (cfg->msg.address_hi != msg->address_hi) { |
| 46 | pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1); |
| 47 | pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi); |
| 48 | } |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 49 | if (cfg->update) |
| 50 | cfg->update(cfg->dev, irq, msg); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 51 | spin_unlock_irqrestore(&ht_irq_lock, flags); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 52 | cfg->msg = *msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 53 | } |
| 54 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 55 | 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] | 56 | { |
| 57 | struct ht_irq_cfg *cfg = get_irq_data(irq); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 58 | *msg = cfg->msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 59 | } |
| 60 | |
| 61 | void mask_ht_irq(unsigned int irq) |
| 62 | { |
| 63 | struct ht_irq_cfg *cfg; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 64 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 65 | |
| 66 | cfg = get_irq_data(irq); |
| 67 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 68 | msg = cfg->msg; |
| 69 | msg.address_lo |= 1; |
| 70 | write_ht_irq_msg(irq, &msg); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 71 | } |
| 72 | |
| 73 | void unmask_ht_irq(unsigned int irq) |
| 74 | { |
| 75 | struct ht_irq_cfg *cfg; |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 76 | struct ht_irq_msg msg; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 77 | |
| 78 | cfg = get_irq_data(irq); |
| 79 | |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 80 | msg = cfg->msg; |
| 81 | msg.address_lo &= ~1; |
| 82 | write_ht_irq_msg(irq, &msg); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 83 | } |
| 84 | |
| 85 | /** |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 86 | * __ht_create_irq - create an irq and attach it to a device. |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 87 | * @dev: The hypertransport device to find the irq capability on. |
| 88 | * @idx: Which of the possible irqs to attach to. |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 89 | * @update: Function to be called when changing the htirq message |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 90 | * |
| 91 | * The irq number of the new irq or a negative error value is returned. |
| 92 | */ |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 93 | int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update) |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 94 | { |
| 95 | struct ht_irq_cfg *cfg; |
| 96 | unsigned long flags; |
| 97 | u32 data; |
| 98 | int max_irq; |
| 99 | int pos; |
| 100 | int irq; |
| 101 | |
Michael Ellerman | 120a50d | 2006-11-22 18:26:19 +1100 | [diff] [blame^] | 102 | pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 103 | if (!pos) |
| 104 | return -EINVAL; |
| 105 | |
| 106 | /* Verify the idx I want to use is in range */ |
| 107 | spin_lock_irqsave(&ht_irq_lock, flags); |
| 108 | pci_write_config_byte(dev, pos + 2, 1); |
| 109 | pci_read_config_dword(dev, pos + 4, &data); |
| 110 | spin_unlock_irqrestore(&ht_irq_lock, flags); |
| 111 | |
| 112 | max_irq = (data >> 16) & 0xff; |
| 113 | if ( idx > max_irq) |
| 114 | return -EINVAL; |
| 115 | |
| 116 | cfg = kmalloc(sizeof(*cfg), GFP_KERNEL); |
| 117 | if (!cfg) |
| 118 | return -ENOMEM; |
| 119 | |
| 120 | cfg->dev = dev; |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 121 | cfg->update = update; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 122 | cfg->pos = pos; |
| 123 | cfg->idx = 0x10 + (idx * 2); |
Eric W. Biederman | ec68307 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 124 | /* Initialize msg to a value that will never match the first write. */ |
| 125 | cfg->msg.address_lo = 0xffffffff; |
| 126 | cfg->msg.address_hi = 0xffffffff; |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 127 | |
| 128 | irq = create_irq(); |
| 129 | if (irq < 0) { |
| 130 | kfree(cfg); |
| 131 | return -EBUSY; |
| 132 | } |
| 133 | set_irq_data(irq, cfg); |
| 134 | |
| 135 | if (arch_setup_ht_irq(irq, dev) < 0) { |
| 136 | ht_destroy_irq(irq); |
| 137 | return -EBUSY; |
| 138 | } |
| 139 | |
| 140 | return irq; |
| 141 | } |
| 142 | |
| 143 | /** |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 144 | * ht_create_irq - create an irq and attach it to a device. |
| 145 | * @dev: The hypertransport device to find the irq capability on. |
| 146 | * @idx: Which of the possible irqs to attach to. |
| 147 | * |
| 148 | * ht_create_irq needs to be called for all hypertransport devices |
| 149 | * that generate irqs. |
| 150 | * |
| 151 | * The irq number of the new irq or a negative error value is returned. |
| 152 | */ |
| 153 | int ht_create_irq(struct pci_dev *dev, int idx) |
| 154 | { |
| 155 | return __ht_create_irq(dev, idx, NULL); |
| 156 | } |
| 157 | |
| 158 | /** |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 159 | * ht_destroy_irq - destroy an irq created with ht_create_irq |
| 160 | * |
| 161 | * This reverses ht_create_irq removing the specified irq from |
| 162 | * existence. The irq should be free before this happens. |
| 163 | */ |
| 164 | void ht_destroy_irq(unsigned int irq) |
| 165 | { |
| 166 | struct ht_irq_cfg *cfg; |
| 167 | |
| 168 | cfg = get_irq_data(irq); |
| 169 | set_irq_chip(irq, NULL); |
| 170 | set_irq_data(irq, NULL); |
| 171 | destroy_irq(irq); |
| 172 | |
| 173 | kfree(cfg); |
| 174 | } |
| 175 | |
Eric W. Biederman | 43539c38 | 2006-11-08 17:44:57 -0800 | [diff] [blame] | 176 | EXPORT_SYMBOL(__ht_create_irq); |
Eric W. Biederman | 8b955b0 | 2006-10-04 02:16:55 -0700 | [diff] [blame] | 177 | EXPORT_SYMBOL(ht_create_irq); |
| 178 | EXPORT_SYMBOL(ht_destroy_irq); |