Initial import

1 files changed, 170 insertions, 0 deletions

diff --git a/drivers/pci/htirq.c b/drivers/pci/htirq.c
new file mode 100644
index 000000000..a94dd2c41
--- /dev/null
+++ b/drivers/pci/htirq.c
@@ -0,0 +1,170 @@
+/*
+ * 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/export.h>
+#include <linux/slab.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 = irq_get_handler_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 = irq_get_handler_data(irq);
+	*msg = cfg->msg;
+}
+
+void mask_ht_irq(struct irq_data *data)
+{
+	struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
+	struct ht_irq_msg msg = cfg->msg;
+
+	msg.address_lo |= 1;
+	write_ht_irq_msg(data->irq, &msg);
+}
+
+void unmask_ht_irq(struct irq_data *data)
+{
+	struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
+	struct ht_irq_msg msg = cfg->msg;
+
+	msg.address_lo &= ~1;
+	write_ht_irq_msg(data->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;
+	int max_irq, pos, irq;
+	unsigned long flags;
+	u32 data;
+
+	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 = irq_alloc_hwirq(dev_to_node(&dev->dev));
+	if (!irq) {
+		kfree(cfg);
+		return -EBUSY;
+	}
+	irq_set_handler_data(irq, cfg);
+
+	if (arch_setup_ht_irq(irq, dev) < 0) {
+		ht_destroy_irq(irq);
+		return -EBUSY;
+	}
+
+	return irq;
+}
+EXPORT_SYMBOL(__ht_create_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);
+}
+EXPORT_SYMBOL(ht_create_irq);
+
+/**
+ * ht_destroy_irq - destroy an irq created with ht_create_irq
+ * @irq: irq to be destroyed
+ *
+ * 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 = irq_get_handler_data(irq);
+	irq_set_chip(irq, NULL);
+	irq_set_handler_data(irq, NULL);
+	irq_free_hwirq(irq);
+
+	kfree(cfg);
+}
+EXPORT_SYMBOL(ht_destroy_irq);