This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / pci / htirq.c

diff --git a/drivers/pci/htirq.c b/drivers/pci/htirq.c
new file mode 100644 (file)
index 0000000..279c940
--- /dev/null
+++ b/drivers/pci/htirq.c
@@ -0,0 +1,178 @@
+/*
+ * File:       htirq.c
+ * Purpose:    Hypertransport Interrupt Capability
+ *
+ * Copyright (C) 2006 Linux Networx
+ * Copyright (C) Eric Biederman <ebiederman@lnxi.com>
+ */
+
+#include <linux/irq.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/gfp.h>
+#include <linux/htirq.h>
+
+/* Global ht irq lock.
+ *
+ * This is needed to serialize access to the data port in hypertransport
+ * irq capability.
+ *
+ * With multiple simultaneous hypertransport irq devices it might pay
+ * to make this more fine grained.  But start with simple, stupid, and correct.
+ */
+static DEFINE_SPINLOCK(ht_irq_lock);
+
+struct ht_irq_cfg {
+       struct pci_dev *dev;
+        /* Update callback used to cope with buggy hardware */
+       ht_irq_update_t *update;
+       unsigned pos;
+       unsigned idx;
+       struct ht_irq_msg msg;
+};
+
+
+void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
+{
+       struct ht_irq_cfg *cfg = get_irq_data(irq);
+       unsigned long flags;
+       spin_lock_irqsave(&ht_irq_lock, flags);
+       if (cfg->msg.address_lo != msg->address_lo) {
+               pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
+               pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo);
+       }
+       if (cfg->msg.address_hi != msg->address_hi) {
+               pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
+               pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi);
+       }
+       if (cfg->update)
+               cfg->update(cfg->dev, irq, msg);
+       spin_unlock_irqrestore(&ht_irq_lock, flags);
+       cfg->msg = *msg;
+}
+
+void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
+{
+       struct ht_irq_cfg *cfg = get_irq_data(irq);
+       *msg = cfg->msg;
+}
+
+void mask_ht_irq(unsigned int irq)
+{
+       struct ht_irq_cfg *cfg;
+       struct ht_irq_msg msg;
+
+       cfg = get_irq_data(irq);
+
+       msg = cfg->msg;
+       msg.address_lo |= 1;
+       write_ht_irq_msg(irq, &msg);
+}
+
+void unmask_ht_irq(unsigned int irq)
+{
+       struct ht_irq_cfg *cfg;
+       struct ht_irq_msg msg;
+
+       cfg = get_irq_data(irq);
+
+       msg = cfg->msg;
+       msg.address_lo &= ~1;
+       write_ht_irq_msg(irq, &msg);
+}
+
+/**
+ * __ht_create_irq - create an irq and attach it to a device.
+ * @dev: The hypertransport device to find the irq capability on.
+ * @idx: Which of the possible irqs to attach to.
+ * @update: Function to be called when changing the htirq message
+ *
+ * The irq number of the new irq or a negative error value is returned.
+ */
+int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
+{
+       struct ht_irq_cfg *cfg;
+       unsigned long flags;
+       u32 data;
+       int max_irq;
+       int pos;
+       int irq;
+
+       pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ);
+       if (!pos)
+               return -EINVAL;
+
+       /* Verify the idx I want to use is in range */
+       spin_lock_irqsave(&ht_irq_lock, flags);
+       pci_write_config_byte(dev, pos + 2, 1);
+       pci_read_config_dword(dev, pos + 4, &data);
+       spin_unlock_irqrestore(&ht_irq_lock, flags);
+
+       max_irq = (data >> 16) & 0xff;
+       if ( idx > max_irq)
+               return -EINVAL;
+
+       cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
+       if (!cfg)
+               return -ENOMEM;
+
+       cfg->dev = dev;
+       cfg->update = update;
+       cfg->pos = pos;
+       cfg->idx = 0x10 + (idx * 2);
+       /* Initialize msg to a value that will never match the first write. */
+       cfg->msg.address_lo = 0xffffffff;
+       cfg->msg.address_hi = 0xffffffff;
+
+       irq = create_irq();
+       if (irq < 0) {
+               kfree(cfg);
+               return -EBUSY;
+       }
+       set_irq_data(irq, cfg);
+
+       if (arch_setup_ht_irq(irq, dev) < 0) {
+               ht_destroy_irq(irq);
+               return -EBUSY;
+       }
+
+       return irq;
+}
+
+/**
+ * ht_create_irq - create an irq and attach it to a device.
+ * @dev: The hypertransport device to find the irq capability on.
+ * @idx: Which of the possible irqs to attach to.
+ *
+ * ht_create_irq needs to be called for all hypertransport devices
+ * that generate irqs.
+ *
+ * The irq number of the new irq or a negative error value is returned.
+ */
+int ht_create_irq(struct pci_dev *dev, int idx)
+{
+       return __ht_create_irq(dev, idx, NULL);
+}
+
+/**
+ * ht_destroy_irq - destroy an irq created with ht_create_irq
+ *
+ * This reverses ht_create_irq removing the specified irq from
+ * existence.  The irq should be free before this happens.
+ */
+void ht_destroy_irq(unsigned int irq)
+{
+       struct ht_irq_cfg *cfg;
+
+       cfg = get_irq_data(irq);
+       set_irq_chip(irq, NULL);
+       set_irq_data(irq, NULL);
+       destroy_irq(irq);
+
+       kfree(cfg);
+}
+
+EXPORT_SYMBOL(__ht_create_irq);
+EXPORT_SYMBOL(ht_create_irq);
+EXPORT_SYMBOL(ht_destroy_irq);