kernel-ark/drivers/pci/htirq.c
Jiang Liu 49e07d8f28 x86/htirq: Use hierarchical irqdomain to manage Hypertransport interrupts
We have slightly changed the architecture interfaces to support htirq
PCI driver. It's safe because currently Hypertransport interrupt is
only enabled on x86 platforms.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/1428905519-23704-22-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-24 15:36:50 +02:00

135 lines
3.5 KiB
C

/*
* 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);
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)
{
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;
irq = arch_setup_ht_irq(idx, pos, dev, update);
if (irq > 0)
dev_dbg(&dev->dev, "irq %d for HT\n", irq);
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)
{
arch_teardown_ht_irq(irq);
}
EXPORT_SYMBOL(ht_destroy_irq);