/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* PIC driver for the 8259A Master and Slave PICs in PC/AT machines.
*/
#include <sys/cdefs.h>
#include "opt_auto_eoi.h"
#include "opt_isa.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/asan.h>
#include <sys/bus.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/msan.h>
#include <machine/cpufunc.h>
#include <machine/frame.h>
#include <machine/intr_machdep.h>
#include <machine/md_var.h>
#include <machine/resource.h>
#include <machine/segments.h>
#include <dev/ic/i8259.h>
#include <x86/isa/icu.h>
#include <isa/isareg.h>
#include <isa/isavar.h>
#ifdef __amd64__
#define SDT_ATPIC SDT_SYSIGT
#define GSEL_ATPIC 0
#else
#define SDT_ATPIC SDT_SYS386IGT
#define GSEL_ATPIC GSEL(GCODE_SEL, SEL_KPL)
#endif
#define MASTER 0
#define SLAVE 1
#define IMEN_MASK(ai) (IRQ_MASK((ai)->at_irq))
#define NUM_ISA_IRQS 16
static void atpic_init(void *dummy);
inthand_t
IDTVEC(atpic_intr0), IDTVEC(atpic_intr1), IDTVEC(atpic_intr2),
IDTVEC(atpic_intr3), IDTVEC(atpic_intr4), IDTVEC(atpic_intr5),
IDTVEC(atpic_intr6), IDTVEC(atpic_intr7), IDTVEC(atpic_intr8),
IDTVEC(atpic_intr9), IDTVEC(atpic_intr10), IDTVEC(atpic_intr11),
IDTVEC(atpic_intr12), IDTVEC(atpic_intr13), IDTVEC(atpic_intr14),
IDTVEC(atpic_intr15);
/* XXXKIB i386 uses stubs until pti comes */
inthand_t
IDTVEC(atpic_intr0_pti), IDTVEC(atpic_intr1_pti),
IDTVEC(atpic_intr2_pti), IDTVEC(atpic_intr3_pti),
IDTVEC(atpic_intr4_pti), IDTVEC(atpic_intr5_pti),
IDTVEC(atpic_intr6_pti), IDTVEC(atpic_intr7_pti),
IDTVEC(atpic_intr8_pti), IDTVEC(atpic_intr9_pti),
IDTVEC(atpic_intr10_pti), IDTVEC(atpic_intr11_pti),
IDTVEC(atpic_intr12_pti), IDTVEC(atpic_intr13_pti),
IDTVEC(atpic_intr14_pti), IDTVEC(atpic_intr15_pti);
#define IRQ(ap, ai) ((ap)->at_irqbase + (ai)->at_irq)
#define ATPIC(io, base, eoi) { \
.at_pic = { \
.pic_register_sources = atpic_register_sources, \
.pic_enable_source = atpic_enable_source, \
.pic_disable_source = atpic_disable_source, \
.pic_eoi_source = (eoi), \
.pic_enable_intr = atpic_enable_intr, \
.pic_disable_intr = atpic_disable_intr, \
.pic_vector = atpic_vector, \
.pic_source_pending = atpic_source_pending, \
.pic_resume = atpic_resume, \
.pic_config_intr = atpic_config_intr, \
.pic_assign_cpu = atpic_assign_cpu \
}, \
.at_ioaddr = (io), \
.at_irqbase = (base), \
.at_intbase = IDT_IO_INTS + (base), \
.at_imen = 0xff, \
}
#define INTSRC(irq) \
{ { &atpics[(irq) / 8].at_pic }, IDTVEC(atpic_intr ## irq ), \
IDTVEC(atpic_intr ## irq ## _pti), (irq) % 8 }
struct atpic {
struct pic at_pic;
int at_ioaddr;
int at_irqbase;
uint8_t at_intbase;
uint8_t at_imen;
};
struct atpic_intsrc {
struct intsrc at_intsrc;
inthand_t *at_intr, *at_intr_pti;
int at_irq; /* Relative to PIC base. */
enum intr_trigger at_trigger;
u_long at_count;
u_long at_straycount;
};
static void atpic_register_sources(struct pic *pic);
static void atpic_enable_source(struct intsrc *isrc);
static void atpic_disable_source(struct intsrc *isrc, int eoi);
static void atpic_eoi_master(struct intsrc *isrc);
static void atpic_eoi_slave(struct intsrc *isrc);
static void atpic_enable_intr(struct intsrc *isrc);
static void atpic_disable_intr(struct intsrc *isrc);
static int atpic_vector(struct intsrc *isrc);
static void atpic_resume(struct pic *pic, bool suspend_cancelled);
static int atpic_source_pending(struct intsrc *isrc);
static int atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig,
enum intr_polarity pol);
static int atpic_assign_cpu(struct intsrc *isrc, u_int apic_id);
static void i8259_init(struct atpic *pic, int slave);
static struct atpic atpics[] = {
ATPIC(IO_ICU1, 0, atpic_eoi_master),
ATPIC(IO_ICU2, 8, atpic_eoi_slave)
};
static struct atpic_intsrc atintrs[] = {
INTSRC(0),
INTSRC(1),
INTSRC(2),
INTSRC(3),
INTSRC(4),
INTSRC(5),
INTSRC(6),
INTSRC(7),
INTSRC(8),
INTSRC(9),
INTSRC(10),
INTSRC(11),
INTSRC(12),
INTSRC(13),
INTSRC(14),
INTSRC(15),
};
CTASSERT(nitems(atintrs) == NUM_ISA_IRQS);
static __inline void
_atpic_eoi_master(struct intsrc *isrc)
{
KASSERT(isrc->is_pic == &atpics[MASTER].at_pic,
("%s: mismatched pic", __func__));
#ifndef AUTO_EOI_1
outb(atpics[MASTER].at_ioaddr, OCW2_EOI);
#endif
}
/*
* The data sheet says no auto-EOI on slave, but it sometimes works.
* So, if AUTO_EOI_2 is enabled, we use it.
*/
static __inline void
_atpic_eoi_slave(struct intsrc *isrc)
{
KASSERT(isrc->is_pic == &atpics[SLAVE].at_pic,
("%s: mismatched pic", __func__));
#ifndef AUTO_EOI_2
outb(atpics[SLAVE].at_ioaddr, OCW2_EOI);
#ifndef AUTO_EOI_1
outb(atpics[MASTER].at_ioaddr, OCW2_EOI);
#endif
#endif
}
static void
atpic_register_sources(struct pic *pic)
{
struct atpic *ap = (struct atpic *)pic;
struct atpic_intsrc *ai;
int i;
/*
* If any of the ISA IRQs have an interrupt source already, then
* assume that the I/O APICs are being used and don't register any
* of our interrupt sources. This makes sure we don't accidentally
* use mixed mode. The "accidental" use could otherwise occur on
* machines that route the ACPI SCI interrupt to a different ISA
* IRQ (at least one machine routes it to IRQ 13) thus disabling
* that APIC ISA routing and allowing the ATPIC source for that IRQ
* to leak through. We used to depend on this feature for routing
* IRQ0 via mixed mode, but now we don't use mixed mode at all.
*
* To avoid the slave not register sources after the master
* registers its sources, register all IRQs when this function is
* called on the master.
*/
if (ap != &atpics[MASTER])
return;
for (i = 0; i < NUM_ISA_IRQS; i++)
if (intr_lookup_source(i) != NULL)
return;
/* Loop through all interrupt sources and add them. */
for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) {
if (i == ICU_SLAVEID)
continue;
intr_register_source(&ai->at_intsrc);
}
}
static void
atpic_enable_source(struct intsrc *isrc)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
spinlock_enter();
if (ap->at_imen & IMEN_MASK(ai)) {
ap->at_imen &= ~IMEN_MASK(ai);
outb(ap->at_ioaddr + ICU_IMR_OFFSET, ap->at_imen);
}
spinlock_exit();
}
static void
atpic_disable_source(struct intsrc *isrc, int eoi)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
spinlock_enter();
if (ai->at_trigger != INTR_TRIGGER_EDGE) {
ap->at_imen |= IMEN_MASK(ai);
outb(ap->at_ioaddr + ICU_IMR_OFFSET, ap->at_imen);
}
/*
* Take care to call these functions directly instead of through
* a function pointer. All of the referenced variables should
* still be hot in the cache.
*/
if (eoi == PIC_EOI) {
if (isrc->is_pic == &atpics[MASTER].at_pic)
_atpic_eoi_master(isrc);
else
_atpic_eoi_slave(isrc);
}
spinlock_exit();
}
static void
atpic_eoi_master(struct intsrc *isrc)
{
#ifndef AUTO_EOI_1
spinlock_enter();
_atpic_eoi_master(isrc);
spinlock_exit();
#endif
}
static void
atpic_eoi_slave(struct intsrc *isrc)
{
#ifndef AUTO_EOI_2
spinlock_enter();
_atpic_eoi_slave(isrc);
spinlock_exit();
#endif
}
static void
atpic_enable_intr(struct intsrc *isrc)
{
}
static void
atpic_disable_intr(struct intsrc *isrc)
{
}
static int
atpic_vector(struct intsrc *isrc)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
return (IRQ(ap, ai));
}
static int
atpic_source_pending(struct intsrc *isrc)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
return (inb(ap->at_ioaddr) & IMEN_MASK(ai));
}
static void
atpic_resume(struct pic *pic, bool suspend_cancelled)
{
struct atpic *ap = (struct atpic *)pic;
i8259_init(ap, ap == &atpics[SLAVE]);
if (ap == &atpics[SLAVE] && elcr_found)
elcr_resume();
}
static int
atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig,
enum intr_polarity pol)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
u_int vector;
/* Map conforming values to edge/hi and sanity check the values. */
if (trig == INTR_TRIGGER_CONFORM)
trig = INTR_TRIGGER_EDGE;
if (pol == INTR_POLARITY_CONFORM)
pol = INTR_POLARITY_HIGH;
vector = atpic_vector(isrc);
if ((trig == INTR_TRIGGER_EDGE && pol == INTR_POLARITY_LOW) ||
(trig == INTR_TRIGGER_LEVEL && pol == INTR_POLARITY_HIGH)) {
printf(
"atpic: Mismatched config for IRQ%u: trigger %s, polarity %s\n",
vector, trig == INTR_TRIGGER_EDGE ? "edge" : "level",
pol == INTR_POLARITY_HIGH ? "high" : "low");
return (EINVAL);
}
/* If there is no change, just return. */
if (ai->at_trigger == trig)
return (0);
/*
* Certain IRQs can never be level/lo, so don't try to set them
* that way if asked. At least some ELCR registers ignore setting
* these bits as well.
*/
if ((vector == 0 || vector == 1 || vector == 2 || vector == 13) &&
trig == INTR_TRIGGER_LEVEL) {
if (bootverbose)
printf(
"atpic: Ignoring invalid level/low configuration for IRQ%u\n",
vector);
return (EINVAL);
}
if (!elcr_found) {
if (bootverbose)
printf("atpic: No ELCR to configure IRQ%u as %s\n",
vector, trig == INTR_TRIGGER_EDGE ? "edge/high" :
"level/low");
return (ENXIO);
}
if (bootverbose)
printf("atpic: Programming IRQ%u as %s\n", vector,
trig == INTR_TRIGGER_EDGE ? "edge/high" : "level/low");
spinlock_enter();
elcr_write_trigger(atpic_vector(isrc), trig);
ai->at_trigger = trig;
spinlock_exit();
return (0);
}
static int
atpic_assign_cpu(struct intsrc *isrc, u_int apic_id)
{
/*
* 8259A's are only used in UP in which case all interrupts always
* go to the sole CPU and this function shouldn't even be called.
*/
panic("%s: bad cookie", __func__);
}
static void
i8259_init(struct atpic *pic, int slave)
{
int imr_addr;
/* Reset the PIC and program with next four bytes. */
spinlock_enter();
outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4);
imr_addr = pic->at_ioaddr + ICU_IMR_OFFSET;
/* Start vector. */
outb(imr_addr, pic->at_intbase);
/*
* Setup slave links. For the master pic, indicate what line
* the slave is configured on. For the slave indicate
* which line on the master we are connected to.
*/
if (slave)
outb(imr_addr, ICU_SLAVEID);
else
outb(imr_addr, IRQ_MASK(ICU_SLAVEID));
/* Set mode. */
if (slave)
outb(imr_addr, SLAVE_MODE);
else
outb(imr_addr, MASTER_MODE);
/* Set interrupt enable mask. */
outb(imr_addr, pic->at_imen);
/* Reset is finished, default to IRR on read. */
outb(pic->at_ioaddr, OCW3_SEL | OCW3_RR);
/* OCW2_L1 sets priority order to 3-7, 0-2 (com2 first). */
if (!slave)
outb(pic->at_ioaddr, OCW2_R | OCW2_SL | OCW2_L1);
spinlock_exit();
}
void
atpic_startup(void)
{
struct atpic_intsrc *ai;
int i;
/* Start off with all interrupts disabled. */
i8259_init(&atpics[MASTER], 0);
i8259_init(&atpics[SLAVE], 1);
atpic_enable_source((struct intsrc *)&atintrs[ICU_SLAVEID]);
/* Install low-level interrupt handlers for all of our IRQs. */
for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) {
if (i == ICU_SLAVEID)
continue;
ai->at_intsrc.is_count = &ai->at_count;
ai->at_intsrc.is_straycount = &ai->at_straycount;
setidt(((struct atpic *)ai->at_intsrc.is_pic)->at_intbase +
ai->at_irq, pti ? ai->at_intr_pti : ai->at_intr, SDT_ATPIC,
SEL_KPL, GSEL_ATPIC);
}
/*
* Look for an ELCR. If we find one, update the trigger modes.
* If we don't find one, assume that IRQs 0, 1, 2, and 13 are
* edge triggered and that everything else is level triggered.
* We only use the trigger information to reprogram the ELCR if
* we have one and as an optimization to avoid masking edge
* triggered interrupts. For the case that we don't have an ELCR,
* it doesn't hurt to mask an edge triggered interrupt, so we
* assume level trigger for any interrupt that we aren't sure is
* edge triggered.
*/
if (elcr_found) {
for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++)
ai->at_trigger = elcr_read_trigger(i);
} else {
for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++)
switch (i) {
case 0:
case 1:
case 2:
case 8:
case 13:
ai->at_trigger = INTR_TRIGGER_EDGE;
break;
default:
ai->at_trigger = INTR_TRIGGER_LEVEL;
break;
}
}
}
static void
atpic_init(void *dummy __unused)
{
/*
* Register our PICs, even if we aren't going to use any of their
* pins so that they are suspended and resumed.
*/
if (intr_register_pic(&atpics[0].at_pic) != 0 ||
intr_register_pic(&atpics[1].at_pic) != 0)
panic("Unable to register ATPICs");
if (num_io_irqs == 0)
num_io_irqs = NUM_ISA_IRQS;
}
SYSINIT(atpic_init, SI_SUB_INTR, SI_ORDER_FOURTH, atpic_init, NULL);
void
atpic_handle_intr(u_int vector, struct trapframe *frame)
{
struct intsrc *isrc;
kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0);
kmsan_mark(frame, sizeof(*frame), KMSAN_STATE_INITED);
trap_check_kstack();
KASSERT(vector < NUM_ISA_IRQS, ("unknown int %u\n", vector));
isrc = &atintrs[vector].at_intsrc;
/*
* If we don't have an event, see if this is a spurious
* interrupt.
*/
if (isrc->is_event == NULL && (vector == 7 || vector == 15)) {
int port, isr;
/*
* Read the ISR register to see if IRQ 7/15 is really
* pending. Reset read register back to IRR when done.
*/
port = ((struct atpic *)isrc->is_pic)->at_ioaddr;
spinlock_enter();
outb(port, OCW3_SEL | OCW3_RR | OCW3_RIS);
isr = inb(port);
outb(port, OCW3_SEL | OCW3_RR);
spinlock_exit();
if ((isr & IRQ_MASK(7)) == 0)
return;
}
intr_execute_handlers(isrc, frame);
}
#ifdef DEV_ISA
/*
* Bus attachment for the ISA PIC.
*/
static struct isa_pnp_id atpic_ids[] = {
{ 0x0000d041 /* PNP0000 */, "AT interrupt controller" },
{ 0 }
};
static int
atpic_probe(device_t dev)
{
int result;
result = ISA_PNP_PROBE(device_get_parent(dev), dev, atpic_ids);
if (result <= 0)
device_quiet(dev);
return (result);
}
/*
* We might be granted IRQ 2, as this is typically consumed by chaining
* between the two PIC components. If we're using the APIC, however,
* this may not be the case, and as such we should free the resource.
* (XXX untested)
*
* The generic ISA attachment code will handle allocating any other resources
* that we don't explicitly claim here.
*/
static int
atpic_attach(device_t dev)
{
struct resource *res;
int rid;
/* Try to allocate our IRQ and then free it. */
rid = 0;
res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, 0);
if (res != NULL)
bus_release_resource(dev, SYS_RES_IRQ, rid, res);
return (0);
}
static device_method_t atpic_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, atpic_probe),
DEVMETHOD(device_attach, atpic_attach),
DEVMETHOD(device_detach, bus_generic_detach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, bus_generic_suspend),
DEVMETHOD(device_resume, bus_generic_resume),
{ 0, 0 }
};
static driver_t atpic_driver = {
"atpic",
atpic_methods,
1, /* no softc */
};
DRIVER_MODULE(atpic, isa, atpic_driver, 0, 0);
DRIVER_MODULE(atpic, acpi, atpic_driver, 0, 0);
ISA_PNP_INFO(atpic_ids);
#endif /* DEV_ISA */
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