interrupt.c

linux 内核源代码

/*
 *  PS3 interrupt routines.
 *
 *  Copyright (C) 2006 Sony Computer Entertainment Inc.
 *  Copyright 2006 Sony Corp.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/irq.h>

#include <asm/machdep.h>
#include <asm/udbg.h>
#include <asm/lv1call.h>
#include <asm/smp.h>

#include "platform.h"

#if defined(DEBUG)
#define DBG udbg_printf
#else
#define DBG pr_debug
#endif

/**
 * struct ps3_bmp - a per cpu irq status and mask bitmap structure
 * @status: 256 bit status bitmap indexed by plug
 * @unused_1:
 * @mask: 256 bit mask bitmap indexed by plug
 * @unused_2:
 * @lock:
 * @ipi_debug_brk_mask:
 *
 * The HV mantains per SMT thread mappings of HV outlet to HV plug on
 * behalf of the guest.  These mappings are implemented as 256 bit guest
 * supplied bitmaps indexed by plug number.  The addresses of the bitmaps
 * are registered with the HV through lv1_configure_irq_state_bitmap().
 * The HV requires that the 512 bits of status + mask not cross a page
 * boundary.  PS3_BMP_MINALIGN is used to define this minimal 64 byte
 * alignment.
 *
 * The HV supports 256 plugs per thread, assigned as {0..255}, for a total
 * of 512 plugs supported on a processor.  To simplify the logic this
 * implementation equates HV plug value to Linux virq value, constrains each
 * interrupt to have a system wide unique plug number, and limits the range
 * of the plug values to map into the first dword of the bitmaps.  This
 * gives a usable range of plug values of  {NUM_ISA_INTERRUPTS..63}.  Note
 * that there is no constraint on how many in this set an individual thread
 * can acquire.
 */

#define PS3_BMP_MINALIGN 64

struct ps3_bmp {
	struct {
		u64 status;
		u64 unused_1[3];
		u64 mask;
		u64 unused_2[3];
	};
	u64 ipi_debug_brk_mask;
	spinlock_t lock;
};

/**
 * struct ps3_private - a per cpu data structure
 * @bmp: ps3_bmp structure
 * @ppe_id: HV logical_ppe_id
 * @thread_id: HV thread_id
 */

struct ps3_private {
	struct ps3_bmp bmp __attribute__ ((aligned (PS3_BMP_MINALIGN)));
	u64 ppe_id;
	u64 thread_id;
};

static DEFINE_PER_CPU(struct ps3_private, ps3_private);

/**
 * ps3_chip_mask - Set an interrupt mask bit in ps3_bmp.
 * @virq: The assigned Linux virq.
 *
 * Sets ps3_bmp.mask and calls lv1_did_update_interrupt_mask().
 */

static void ps3_chip_mask(unsigned int virq)
{
	struct ps3_private *pd = get_irq_chip_data(virq);
	unsigned long flags;

	pr_debug("%s:%d: thread_id %lu, virq %d\n", __func__, __LINE__,
		pd->thread_id, virq);

	local_irq_save(flags);
	clear_bit(63 - virq, &pd->bmp.mask);
	lv1_did_update_interrupt_mask(pd->ppe_id, pd->thread_id);
	local_irq_restore(flags);
}

/**
 * ps3_chip_unmask - Clear an interrupt mask bit in ps3_bmp.
 * @virq: The assigned Linux virq.
 *
 * Clears ps3_bmp.mask and calls lv1_did_update_interrupt_mask().
 */

static void ps3_chip_unmask(unsigned int virq)
{
	struct ps3_private *pd = get_irq_chip_data(virq);
	unsigned long flags;

	pr_debug("%s:%d: thread_id %lu, virq %d\n", __func__, __LINE__,
		pd->thread_id, virq);

	local_irq_save(flags);
	set_bit(63 - virq, &pd->bmp.mask);
	lv1_did_update_interrupt_mask(pd->ppe_id, pd->thread_id);
	local_irq_restore(flags);
}

/**
 * ps3_chip_eoi - HV end-of-interrupt.
 * @virq: The assigned Linux virq.
 *
 * Calls lv1_end_of_interrupt_ext().
 */

static void ps3_chip_eoi(unsigned int virq)
{
	const struct ps3_private *pd = get_irq_chip_data(virq);
	lv1_end_of_interrupt_ext(pd->ppe_id, pd->thread_id, virq);
}

/**
 * ps3_irq_chip - Represents the ps3_bmp as a Linux struct irq_chip.
 */

static struct irq_chip ps3_irq_chip = {
	.typename = "ps3",
	.mask = ps3_chip_mask,
	.unmask = ps3_chip_unmask,
	.eoi = ps3_chip_eoi,
};

/**
 * ps3_virq_setup - virq related setup.
 * @cpu: enum ps3_cpu_binding indicating the cpu the interrupt should be
 * serviced on.
 * @outlet: The HV outlet from the various create outlet routines.
 * @virq: The assigned Linux virq.
 *
 * Calls irq_create_mapping() to get a virq and sets the chip data to
 * ps3_private data.
 */

int ps3_virq_setup(enum ps3_cpu_binding cpu, unsigned long outlet,
	unsigned int *virq)
{
	int result;
	struct ps3_private *pd;

	/* This defines the default interrupt distribution policy. */

	if (cpu == PS3_BINDING_CPU_ANY)
		cpu = 0;

	pd = &per_cpu(ps3_private, cpu);

	*virq = irq_create_mapping(NULL, outlet);

	if (*virq == NO_IRQ) {
		pr_debug("%s:%d: irq_create_mapping failed: outlet %lu\n",
			__func__, __LINE__, outlet);
		result = -ENOMEM;
		goto fail_create;
	}

	pr_debug("%s:%d: outlet %lu => cpu %u, virq %u\n", __func__, __LINE__,
		outlet, cpu, *virq);

	result = set_irq_chip_data(*virq, pd);

	if (result) {
		pr_debug("%s:%d: set_irq_chip_data failed\n",
			__func__, __LINE__);
		goto fail_set;
	}

	ps3_chip_mask(*virq);

	return result;

fail_set:
	irq_dispose_mapping(*virq);
fail_create:
	return result;
}

/**
 * ps3_virq_destroy - virq related teardown.
 * @virq: The assigned Linux virq.
 *
 * Clears chip data and calls irq_dispose_mapping() for the virq.
 */

int ps3_virq_destroy(unsigned int virq)
{
	const struct ps3_private *pd = get_irq_chip_data(virq);

	pr_debug("%s:%d: ppe_id %lu, thread_id %lu, virq %u\n", __func__,
		__LINE__, pd->ppe_id, pd->thread_id, virq);

	set_irq_chip_data(virq, NULL);
	irq_dispose_mapping(virq);

	pr_debug("%s:%d <-\n", __func__, __LINE__);
	return 0;
}

/**
 * ps3_irq_plug_setup - Generic outlet and virq related setup.
 * @cpu: enum ps3_cpu_binding indicating the cpu the interrupt should be
 * serviced on.
 * @outlet: The HV outlet from the various create outlet routines.
 * @virq: The assigned Linux virq.
 *
 * Sets up virq and connects the irq plug.
 */

int ps3_irq_plug_setup(enum ps3_cpu_binding cpu, unsigned long outlet,
	unsigned int *virq)
{
	int result;
	struct ps3_private *pd;

	result = ps3_virq_setup(cpu, outlet, virq);

	if (result) {
		pr_debug("%s:%d: ps3_virq_setup failed\n", __func__, __LINE__);
		goto fail_setup;
	}

	pd = get_irq_chip_data(*virq);

	/* Binds outlet to cpu + virq. */

	result = lv1_connect_irq_plug_ext(pd->ppe_id, pd->thread_id, *virq,
		outlet, 0);

	if (result) {
		pr_info("%s:%d: lv1_connect_irq_plug_ext failed: %s\n",
		__func__, __LINE__, ps3_result(result));
		result = -EPERM;
		goto fail_connect;
	}

	return result;

fail_connect:
	ps3_virq_destroy(*virq);
fail_setup:
	return result;
}
EXPORT_SYMBOL_GPL(ps3_irq_plug_setup);

/**
 * ps3_irq_plug_destroy - Generic outlet and virq related teardown.
 * @virq: The assigned Linux virq.
 *
 * Disconnects the irq plug and tears down virq.
 * Do not call for system bus event interrupts setup with
 * ps3_sb_event_receive_port_setup().
 */

int ps3_irq_plug_destroy(unsigned int virq)
{
	int result;
	const struct ps3_private *pd = get_irq_chip_data(virq);

	pr_debug("%s:%d: ppe_id %lu, thread_id %lu, virq %u\n", __func__,
		__LINE__, pd->ppe_id, pd->thread_id, virq);

	ps3_chip_mask(virq);

	result = lv1_disconnect_irq_plug_ext(pd->ppe_id, pd->thread_id, virq);

	if (result)
		pr_info("%s:%d: lv1_disconnect_irq_plug_ext failed: %s\n",
		__func__, __LINE__, ps3_result(result));

	ps3_virq_destroy(virq);

	return result;
}
EXPORT_SYMBOL_GPL(ps3_irq_plug_destroy);

/**
 * ps3_event_receive_port_setup - Setup an event receive port.
 * @cpu: enum ps3_cpu_binding indicating the cpu the interrupt should be
 * serviced on.
 * @virq: The assigned Linux virq.
 *
 * The virq can be used with lv1_connect_interrupt_event_receive_port() to
 * arrange to receive interrupts from system-bus devices, or with
 * ps3_send_event_locally() to signal events.
 */

int ps3_event_receive_port_setup(enum ps3_cpu_binding cpu, unsigned int *virq)
{
	int result;
	unsigned long outlet;

	result = lv1_construct_event_receive_port(&outlet);

	if (result) {
		pr_debug("%s:%d: lv1_construct_event_receive_port failed: %s\n",
			__func__, __LINE__, ps3_result(result));
		*virq = NO_IRQ;
		return result;
	}

	result = ps3_irq_plug_setup(cpu, outlet, virq);
	BUG_ON(result);

	return result;
}
EXPORT_SYMBOL_GPL(ps3_event_receive_port_setup);

/**
 * ps3_event_receive_port_destroy - Destroy an event receive port.
 * @virq: The assigned Linux virq.
 *
 * Since ps3_event_receive_port_destroy destroys the receive port outlet,
 * SB devices need to call disconnect_interrupt_event_receive_port() before
 * this.
 */

int ps3_event_receive_port_destroy(unsigned int virq)
{
	int result;

	pr_debug(" -> %s:%d virq %u\n", __func__, __LINE__, virq);

	ps3_chip_mask(virq);

	result = lv1_destruct_event_receive_port(virq_to_hw(virq));

	if (result)
		pr_debug("%s:%d: lv1_destruct_event_receive_port failed: %s\n",
			__func__, __LINE__, ps3_result(result));

	/*
	 * Don't call ps3_virq_destroy() here since ps3_smp_cleanup_cpu()
	 * calls from interrupt context (smp_call_function) when kexecing.
	 */

	pr_debug(" <- %s:%d\n", __func__, __LINE__);
	return result;
}

int ps3_send_event_locally(unsigned int virq)
{
	return lv1_send_event_locally(virq_to_hw(virq));
}

/**
 * ps3_sb_event_receive_port_setup - Setup a system bus event receive port.
 * @cpu: enum ps3_cpu_binding indicating the cpu the interrupt should be
 * serviced on.
 * @dev: The system bus device instance.
 * @virq: The assigned Linux virq.
 *
 * An event irq represents a virtual device interrupt.  The interrupt_id
 * coresponds to the software interrupt number.