linux/arch/powerpc/sysdev/mpic.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

1291 lines
33 KiB
C

/*
* arch/powerpc/kernel/mpic.c
*
* Driver for interrupt controllers following the OpenPIC standard, the
* common implementation beeing IBM's MPIC. This driver also can deal
* with various broken implementations of this HW.
*
* Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#undef DEBUG
#undef DEBUG_IPI
#undef DEBUG_IRQ
#undef DEBUG_LOW
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/bootmem.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <asm/ptrace.h>
#include <asm/signal.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/machdep.h>
#include <asm/mpic.h>
#include <asm/smp.h>
#ifdef DEBUG
#define DBG(fmt...) printk(fmt)
#else
#define DBG(fmt...)
#endif
static struct mpic *mpics;
static struct mpic *mpic_primary;
static DEFINE_SPINLOCK(mpic_lock);
#ifdef CONFIG_PPC32 /* XXX for now */
#ifdef CONFIG_IRQ_ALL_CPUS
#define distribute_irqs (1)
#else
#define distribute_irqs (0)
#endif
#endif
#ifdef CONFIG_MPIC_WEIRD
static u32 mpic_infos[][MPIC_IDX_END] = {
[0] = { /* Original OpenPIC compatible MPIC */
MPIC_GREG_BASE,
MPIC_GREG_FEATURE_0,
MPIC_GREG_GLOBAL_CONF_0,
MPIC_GREG_VENDOR_ID,
MPIC_GREG_IPI_VECTOR_PRI_0,
MPIC_GREG_IPI_STRIDE,
MPIC_GREG_SPURIOUS,
MPIC_GREG_TIMER_FREQ,
MPIC_TIMER_BASE,
MPIC_TIMER_STRIDE,
MPIC_TIMER_CURRENT_CNT,
MPIC_TIMER_BASE_CNT,
MPIC_TIMER_VECTOR_PRI,
MPIC_TIMER_DESTINATION,
MPIC_CPU_BASE,
MPIC_CPU_STRIDE,
MPIC_CPU_IPI_DISPATCH_0,
MPIC_CPU_IPI_DISPATCH_STRIDE,
MPIC_CPU_CURRENT_TASK_PRI,
MPIC_CPU_WHOAMI,
MPIC_CPU_INTACK,
MPIC_CPU_EOI,
MPIC_IRQ_BASE,
MPIC_IRQ_STRIDE,
MPIC_IRQ_VECTOR_PRI,
MPIC_VECPRI_VECTOR_MASK,
MPIC_VECPRI_POLARITY_POSITIVE,
MPIC_VECPRI_POLARITY_NEGATIVE,
MPIC_VECPRI_SENSE_LEVEL,
MPIC_VECPRI_SENSE_EDGE,
MPIC_VECPRI_POLARITY_MASK,
MPIC_VECPRI_SENSE_MASK,
MPIC_IRQ_DESTINATION
},
[1] = { /* Tsi108/109 PIC */
TSI108_GREG_BASE,
TSI108_GREG_FEATURE_0,
TSI108_GREG_GLOBAL_CONF_0,
TSI108_GREG_VENDOR_ID,
TSI108_GREG_IPI_VECTOR_PRI_0,
TSI108_GREG_IPI_STRIDE,
TSI108_GREG_SPURIOUS,
TSI108_GREG_TIMER_FREQ,
TSI108_TIMER_BASE,
TSI108_TIMER_STRIDE,
TSI108_TIMER_CURRENT_CNT,
TSI108_TIMER_BASE_CNT,
TSI108_TIMER_VECTOR_PRI,
TSI108_TIMER_DESTINATION,
TSI108_CPU_BASE,
TSI108_CPU_STRIDE,
TSI108_CPU_IPI_DISPATCH_0,
TSI108_CPU_IPI_DISPATCH_STRIDE,
TSI108_CPU_CURRENT_TASK_PRI,
TSI108_CPU_WHOAMI,
TSI108_CPU_INTACK,
TSI108_CPU_EOI,
TSI108_IRQ_BASE,
TSI108_IRQ_STRIDE,
TSI108_IRQ_VECTOR_PRI,
TSI108_VECPRI_VECTOR_MASK,
TSI108_VECPRI_POLARITY_POSITIVE,
TSI108_VECPRI_POLARITY_NEGATIVE,
TSI108_VECPRI_SENSE_LEVEL,
TSI108_VECPRI_SENSE_EDGE,
TSI108_VECPRI_POLARITY_MASK,
TSI108_VECPRI_SENSE_MASK,
TSI108_IRQ_DESTINATION
},
};
#define MPIC_INFO(name) mpic->hw_set[MPIC_IDX_##name]
#else /* CONFIG_MPIC_WEIRD */
#define MPIC_INFO(name) MPIC_##name
#endif /* CONFIG_MPIC_WEIRD */
/*
* Register accessor functions
*/
static inline u32 _mpic_read(unsigned int be, volatile u32 __iomem *base,
unsigned int reg)
{
if (be)
return in_be32(base + (reg >> 2));
else
return in_le32(base + (reg >> 2));
}
static inline void _mpic_write(unsigned int be, volatile u32 __iomem *base,
unsigned int reg, u32 value)
{
if (be)
out_be32(base + (reg >> 2), value);
else
out_le32(base + (reg >> 2), value);
}
static inline u32 _mpic_ipi_read(struct mpic *mpic, unsigned int ipi)
{
unsigned int be = (mpic->flags & MPIC_BIG_ENDIAN) != 0;
unsigned int offset = MPIC_INFO(GREG_IPI_VECTOR_PRI_0) +
(ipi * MPIC_INFO(GREG_IPI_STRIDE));
if (mpic->flags & MPIC_BROKEN_IPI)
be = !be;
return _mpic_read(be, mpic->gregs, offset);
}
static inline void _mpic_ipi_write(struct mpic *mpic, unsigned int ipi, u32 value)
{
unsigned int offset = MPIC_INFO(GREG_IPI_VECTOR_PRI_0) +
(ipi * MPIC_INFO(GREG_IPI_STRIDE));
_mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->gregs, offset, value);
}
static inline u32 _mpic_cpu_read(struct mpic *mpic, unsigned int reg)
{
unsigned int cpu = 0;
if (mpic->flags & MPIC_PRIMARY)
cpu = hard_smp_processor_id();
return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN,
mpic->cpuregs[cpu], reg);
}
static inline void _mpic_cpu_write(struct mpic *mpic, unsigned int reg, u32 value)
{
unsigned int cpu = 0;
if (mpic->flags & MPIC_PRIMARY)
cpu = hard_smp_processor_id();
_mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->cpuregs[cpu], reg, value);
}
static inline u32 _mpic_irq_read(struct mpic *mpic, unsigned int src_no, unsigned int reg)
{
unsigned int isu = src_no >> mpic->isu_shift;
unsigned int idx = src_no & mpic->isu_mask;
return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN, mpic->isus[isu],
reg + (idx * MPIC_INFO(IRQ_STRIDE)));
}
static inline void _mpic_irq_write(struct mpic *mpic, unsigned int src_no,
unsigned int reg, u32 value)
{
unsigned int isu = src_no >> mpic->isu_shift;
unsigned int idx = src_no & mpic->isu_mask;
_mpic_write(mpic->flags & MPIC_BIG_ENDIAN, mpic->isus[isu],
reg + (idx * MPIC_INFO(IRQ_STRIDE)), value);
}
#define mpic_read(b,r) _mpic_read(mpic->flags & MPIC_BIG_ENDIAN,(b),(r))
#define mpic_write(b,r,v) _mpic_write(mpic->flags & MPIC_BIG_ENDIAN,(b),(r),(v))
#define mpic_ipi_read(i) _mpic_ipi_read(mpic,(i))
#define mpic_ipi_write(i,v) _mpic_ipi_write(mpic,(i),(v))
#define mpic_cpu_read(i) _mpic_cpu_read(mpic,(i))
#define mpic_cpu_write(i,v) _mpic_cpu_write(mpic,(i),(v))
#define mpic_irq_read(s,r) _mpic_irq_read(mpic,(s),(r))
#define mpic_irq_write(s,r,v) _mpic_irq_write(mpic,(s),(r),(v))
/*
* Low level utility functions
*/
/* Check if we have one of those nice broken MPICs with a flipped endian on
* reads from IPI registers
*/
static void __init mpic_test_broken_ipi(struct mpic *mpic)
{
u32 r;
mpic_write(mpic->gregs, MPIC_INFO(GREG_IPI_VECTOR_PRI_0), MPIC_VECPRI_MASK);
r = mpic_read(mpic->gregs, MPIC_INFO(GREG_IPI_VECTOR_PRI_0));
if (r == le32_to_cpu(MPIC_VECPRI_MASK)) {
printk(KERN_INFO "mpic: Detected reversed IPI registers\n");
mpic->flags |= MPIC_BROKEN_IPI;
}
}
#ifdef CONFIG_MPIC_BROKEN_U3
/* Test if an interrupt is sourced from HyperTransport (used on broken U3s)
* to force the edge setting on the MPIC and do the ack workaround.
*/
static inline int mpic_is_ht_interrupt(struct mpic *mpic, unsigned int source)
{
if (source >= 128 || !mpic->fixups)
return 0;
return mpic->fixups[source].base != NULL;
}
static inline void mpic_ht_end_irq(struct mpic *mpic, unsigned int source)
{
struct mpic_irq_fixup *fixup = &mpic->fixups[source];
if (fixup->applebase) {
unsigned int soff = (fixup->index >> 3) & ~3;
unsigned int mask = 1U << (fixup->index & 0x1f);
writel(mask, fixup->applebase + soff);
} else {
spin_lock(&mpic->fixup_lock);
writeb(0x11 + 2 * fixup->index, fixup->base + 2);
writel(fixup->data, fixup->base + 4);
spin_unlock(&mpic->fixup_lock);
}
}
static void mpic_startup_ht_interrupt(struct mpic *mpic, unsigned int source,
unsigned int irqflags)
{
struct mpic_irq_fixup *fixup = &mpic->fixups[source];
unsigned long flags;
u32 tmp;
if (fixup->base == NULL)
return;
DBG("startup_ht_interrupt(0x%x, 0x%x) index: %d\n",
source, irqflags, fixup->index);
spin_lock_irqsave(&mpic->fixup_lock, flags);
/* Enable and configure */
writeb(0x10 + 2 * fixup->index, fixup->base + 2);
tmp = readl(fixup->base + 4);
tmp &= ~(0x23U);
if (irqflags & IRQ_LEVEL)
tmp |= 0x22;
writel(tmp, fixup->base + 4);
spin_unlock_irqrestore(&mpic->fixup_lock, flags);
}
static void mpic_shutdown_ht_interrupt(struct mpic *mpic, unsigned int source,
unsigned int irqflags)
{
struct mpic_irq_fixup *fixup = &mpic->fixups[source];
unsigned long flags;
u32 tmp;
if (fixup->base == NULL)
return;
DBG("shutdown_ht_interrupt(0x%x, 0x%x)\n", source, irqflags);
/* Disable */
spin_lock_irqsave(&mpic->fixup_lock, flags);
writeb(0x10 + 2 * fixup->index, fixup->base + 2);
tmp = readl(fixup->base + 4);
tmp |= 1;
writel(tmp, fixup->base + 4);
spin_unlock_irqrestore(&mpic->fixup_lock, flags);
}
static void __init mpic_scan_ht_pic(struct mpic *mpic, u8 __iomem *devbase,
unsigned int devfn, u32 vdid)
{
int i, irq, n;
u8 __iomem *base;
u32 tmp;
u8 pos;
for (pos = readb(devbase + PCI_CAPABILITY_LIST); pos != 0;
pos = readb(devbase + pos + PCI_CAP_LIST_NEXT)) {
u8 id = readb(devbase + pos + PCI_CAP_LIST_ID);
if (id == PCI_CAP_ID_HT) {
id = readb(devbase + pos + 3);
if (id == HT_CAPTYPE_IRQ)
break;
}
}
if (pos == 0)
return;
base = devbase + pos;
writeb(0x01, base + 2);
n = (readl(base + 4) >> 16) & 0xff;
printk(KERN_INFO "mpic: - HT:%02x.%x [0x%02x] vendor %04x device %04x"
" has %d irqs\n",
devfn >> 3, devfn & 0x7, pos, vdid & 0xffff, vdid >> 16, n + 1);
for (i = 0; i <= n; i++) {
writeb(0x10 + 2 * i, base + 2);
tmp = readl(base + 4);
irq = (tmp >> 16) & 0xff;
DBG("HT PIC index 0x%x, irq 0x%x, tmp: %08x\n", i, irq, tmp);
/* mask it , will be unmasked later */
tmp |= 0x1;
writel(tmp, base + 4);
mpic->fixups[irq].index = i;
mpic->fixups[irq].base = base;
/* Apple HT PIC has a non-standard way of doing EOIs */
if ((vdid & 0xffff) == 0x106b)
mpic->fixups[irq].applebase = devbase + 0x60;
else
mpic->fixups[irq].applebase = NULL;
writeb(0x11 + 2 * i, base + 2);
mpic->fixups[irq].data = readl(base + 4) | 0x80000000;
}
}
static void __init mpic_scan_ht_pics(struct mpic *mpic)
{
unsigned int devfn;
u8 __iomem *cfgspace;
printk(KERN_INFO "mpic: Setting up HT PICs workarounds for U3/U4\n");
/* Allocate fixups array */
mpic->fixups = alloc_bootmem(128 * sizeof(struct mpic_irq_fixup));
BUG_ON(mpic->fixups == NULL);
memset(mpic->fixups, 0, 128 * sizeof(struct mpic_irq_fixup));
/* Init spinlock */
spin_lock_init(&mpic->fixup_lock);
/* Map U3 config space. We assume all IO-APICs are on the primary bus
* so we only need to map 64kB.
*/
cfgspace = ioremap(0xf2000000, 0x10000);
BUG_ON(cfgspace == NULL);
/* Now we scan all slots. We do a very quick scan, we read the header
* type, vendor ID and device ID only, that's plenty enough
*/
for (devfn = 0; devfn < 0x100; devfn++) {
u8 __iomem *devbase = cfgspace + (devfn << 8);
u8 hdr_type = readb(devbase + PCI_HEADER_TYPE);
u32 l = readl(devbase + PCI_VENDOR_ID);
u16 s;
DBG("devfn %x, l: %x\n", devfn, l);
/* If no device, skip */
if (l == 0xffffffff || l == 0x00000000 ||
l == 0x0000ffff || l == 0xffff0000)
goto next;
/* Check if is supports capability lists */
s = readw(devbase + PCI_STATUS);
if (!(s & PCI_STATUS_CAP_LIST))
goto next;
mpic_scan_ht_pic(mpic, devbase, devfn, l);
next:
/* next device, if function 0 */
if (PCI_FUNC(devfn) == 0 && (hdr_type & 0x80) == 0)
devfn += 7;
}
}
#else /* CONFIG_MPIC_BROKEN_U3 */
static inline int mpic_is_ht_interrupt(struct mpic *mpic, unsigned int source)
{
return 0;
}
static void __init mpic_scan_ht_pics(struct mpic *mpic)
{
}
#endif /* CONFIG_MPIC_BROKEN_U3 */
#define mpic_irq_to_hw(virq) ((unsigned int)irq_map[virq].hwirq)
/* Find an mpic associated with a given linux interrupt */
static struct mpic *mpic_find(unsigned int irq, unsigned int *is_ipi)
{
unsigned int src = mpic_irq_to_hw(irq);
if (irq < NUM_ISA_INTERRUPTS)
return NULL;
if (is_ipi)
*is_ipi = (src >= MPIC_VEC_IPI_0 && src <= MPIC_VEC_IPI_3);
return irq_desc[irq].chip_data;
}
/* Convert a cpu mask from logical to physical cpu numbers. */
static inline u32 mpic_physmask(u32 cpumask)
{
int i;
u32 mask = 0;
for (i = 0; i < NR_CPUS; ++i, cpumask >>= 1)
mask |= (cpumask & 1) << get_hard_smp_processor_id(i);
return mask;
}
#ifdef CONFIG_SMP
/* Get the mpic structure from the IPI number */
static inline struct mpic * mpic_from_ipi(unsigned int ipi)
{
return irq_desc[ipi].chip_data;
}
#endif
/* Get the mpic structure from the irq number */
static inline struct mpic * mpic_from_irq(unsigned int irq)
{
return irq_desc[irq].chip_data;
}
/* Send an EOI */
static inline void mpic_eoi(struct mpic *mpic)
{
mpic_cpu_write(MPIC_INFO(CPU_EOI), 0);
(void)mpic_cpu_read(MPIC_INFO(CPU_WHOAMI));
}
#ifdef CONFIG_SMP
static irqreturn_t mpic_ipi_action(int irq, void *dev_id)
{
smp_message_recv(mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0);
return IRQ_HANDLED;
}
#endif /* CONFIG_SMP */
/*
* Linux descriptor level callbacks
*/
static void mpic_unmask_irq(unsigned int irq)
{
unsigned int loops = 100000;
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
DBG("%p: %s: enable_irq: %d (src %d)\n", mpic, mpic->name, irq, src);
mpic_irq_write(src, MPIC_INFO(IRQ_VECTOR_PRI),
mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) &
~MPIC_VECPRI_MASK);
/* make sure mask gets to controller before we return to user */
do {
if (!loops--) {
printk(KERN_ERR "mpic_enable_irq timeout\n");
break;
}
} while(mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) & MPIC_VECPRI_MASK);
}
static void mpic_mask_irq(unsigned int irq)
{
unsigned int loops = 100000;
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
DBG("%s: disable_irq: %d (src %d)\n", mpic->name, irq, src);
mpic_irq_write(src, MPIC_INFO(IRQ_VECTOR_PRI),
mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) |
MPIC_VECPRI_MASK);
/* make sure mask gets to controller before we return to user */
do {
if (!loops--) {
printk(KERN_ERR "mpic_enable_irq timeout\n");
break;
}
} while(!(mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI)) & MPIC_VECPRI_MASK));
}
static void mpic_end_irq(unsigned int irq)
{
struct mpic *mpic = mpic_from_irq(irq);
#ifdef DEBUG_IRQ
DBG("%s: end_irq: %d\n", mpic->name, irq);
#endif
/* We always EOI on end_irq() even for edge interrupts since that
* should only lower the priority, the MPIC should have properly
* latched another edge interrupt coming in anyway
*/
mpic_eoi(mpic);
}
#ifdef CONFIG_MPIC_BROKEN_U3
static void mpic_unmask_ht_irq(unsigned int irq)
{
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
mpic_unmask_irq(irq);
if (irq_desc[irq].status & IRQ_LEVEL)
mpic_ht_end_irq(mpic, src);
}
static unsigned int mpic_startup_ht_irq(unsigned int irq)
{
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
mpic_unmask_irq(irq);
mpic_startup_ht_interrupt(mpic, src, irq_desc[irq].status);
return 0;
}
static void mpic_shutdown_ht_irq(unsigned int irq)
{
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
mpic_shutdown_ht_interrupt(mpic, src, irq_desc[irq].status);
mpic_mask_irq(irq);
}
static void mpic_end_ht_irq(unsigned int irq)
{
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
#ifdef DEBUG_IRQ
DBG("%s: end_irq: %d\n", mpic->name, irq);
#endif
/* We always EOI on end_irq() even for edge interrupts since that
* should only lower the priority, the MPIC should have properly
* latched another edge interrupt coming in anyway
*/
if (irq_desc[irq].status & IRQ_LEVEL)
mpic_ht_end_irq(mpic, src);
mpic_eoi(mpic);
}
#endif /* !CONFIG_MPIC_BROKEN_U3 */
#ifdef CONFIG_SMP
static void mpic_unmask_ipi(unsigned int irq)
{
struct mpic *mpic = mpic_from_ipi(irq);
unsigned int src = mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0;
DBG("%s: enable_ipi: %d (ipi %d)\n", mpic->name, irq, src);
mpic_ipi_write(src, mpic_ipi_read(src) & ~MPIC_VECPRI_MASK);
}
static void mpic_mask_ipi(unsigned int irq)
{
/* NEVER disable an IPI... that's just plain wrong! */
}
static void mpic_end_ipi(unsigned int irq)
{
struct mpic *mpic = mpic_from_ipi(irq);
/*
* IPIs are marked IRQ_PER_CPU. This has the side effect of
* preventing the IRQ_PENDING/IRQ_INPROGRESS logic from
* applying to them. We EOI them late to avoid re-entering.
* We mark IPI's with IRQF_DISABLED as they must run with
* irqs disabled.
*/
mpic_eoi(mpic);
}
#endif /* CONFIG_SMP */
static void mpic_set_affinity(unsigned int irq, cpumask_t cpumask)
{
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
cpumask_t tmp;
cpus_and(tmp, cpumask, cpu_online_map);
mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION),
mpic_physmask(cpus_addr(tmp)[0]));
}
static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type)
{
/* Now convert sense value */
switch(type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_RISING:
return MPIC_INFO(VECPRI_SENSE_EDGE) |
MPIC_INFO(VECPRI_POLARITY_POSITIVE);
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_EDGE_BOTH:
return MPIC_INFO(VECPRI_SENSE_EDGE) |
MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
case IRQ_TYPE_LEVEL_HIGH:
return MPIC_INFO(VECPRI_SENSE_LEVEL) |
MPIC_INFO(VECPRI_POLARITY_POSITIVE);
case IRQ_TYPE_LEVEL_LOW:
default:
return MPIC_INFO(VECPRI_SENSE_LEVEL) |
MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
}
}
static int mpic_set_irq_type(unsigned int virq, unsigned int flow_type)
{
struct mpic *mpic = mpic_from_irq(virq);
unsigned int src = mpic_irq_to_hw(virq);
struct irq_desc *desc = get_irq_desc(virq);
unsigned int vecpri, vold, vnew;
DBG("mpic: set_irq_type(mpic:@%p,virq:%d,src:0x%x,type:0x%x)\n",
mpic, virq, src, flow_type);
if (src >= mpic->irq_count)
return -EINVAL;
if (flow_type == IRQ_TYPE_NONE)
if (mpic->senses && src < mpic->senses_count)
flow_type = mpic->senses[src];
if (flow_type == IRQ_TYPE_NONE)
flow_type = IRQ_TYPE_LEVEL_LOW;
desc->status &= ~(IRQ_TYPE_SENSE_MASK | IRQ_LEVEL);
desc->status |= flow_type & IRQ_TYPE_SENSE_MASK;
if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
desc->status |= IRQ_LEVEL;
if (mpic_is_ht_interrupt(mpic, src))
vecpri = MPIC_VECPRI_POLARITY_POSITIVE |
MPIC_VECPRI_SENSE_EDGE;
else
vecpri = mpic_type_to_vecpri(mpic, flow_type);
vold = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI));
vnew = vold & ~(MPIC_INFO(VECPRI_POLARITY_MASK) |
MPIC_INFO(VECPRI_SENSE_MASK));
vnew |= vecpri;
if (vold != vnew)
mpic_irq_write(src, MPIC_INFO(IRQ_VECTOR_PRI), vnew);
return 0;
}
static struct irq_chip mpic_irq_chip = {
.mask = mpic_mask_irq,
.unmask = mpic_unmask_irq,
.eoi = mpic_end_irq,
.set_type = mpic_set_irq_type,
};
#ifdef CONFIG_SMP
static struct irq_chip mpic_ipi_chip = {
.mask = mpic_mask_ipi,
.unmask = mpic_unmask_ipi,
.eoi = mpic_end_ipi,
};
#endif /* CONFIG_SMP */
#ifdef CONFIG_MPIC_BROKEN_U3
static struct irq_chip mpic_irq_ht_chip = {
.startup = mpic_startup_ht_irq,
.shutdown = mpic_shutdown_ht_irq,
.mask = mpic_mask_irq,
.unmask = mpic_unmask_ht_irq,
.eoi = mpic_end_ht_irq,
.set_type = mpic_set_irq_type,
};
#endif /* CONFIG_MPIC_BROKEN_U3 */
static int mpic_host_match(struct irq_host *h, struct device_node *node)
{
struct mpic *mpic = h->host_data;
/* Exact match, unless mpic node is NULL */
return mpic->of_node == NULL || mpic->of_node == node;
}
static int mpic_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
struct mpic *mpic = h->host_data;
struct irq_chip *chip;
DBG("mpic: map virq %d, hwirq 0x%lx\n", virq, hw);
if (hw == MPIC_VEC_SPURRIOUS)
return -EINVAL;
#ifdef CONFIG_SMP
else if (hw >= MPIC_VEC_IPI_0) {
WARN_ON(!(mpic->flags & MPIC_PRIMARY));
DBG("mpic: mapping as IPI\n");
set_irq_chip_data(virq, mpic);
set_irq_chip_and_handler(virq, &mpic->hc_ipi,
handle_percpu_irq);
return 0;
}
#endif /* CONFIG_SMP */
if (hw >= mpic->irq_count)
return -EINVAL;
/* Default chip */
chip = &mpic->hc_irq;
#ifdef CONFIG_MPIC_BROKEN_U3
/* Check for HT interrupts, override vecpri */
if (mpic_is_ht_interrupt(mpic, hw))
chip = &mpic->hc_ht_irq;
#endif /* CONFIG_MPIC_BROKEN_U3 */
DBG("mpic: mapping to irq chip @%p\n", chip);
set_irq_chip_data(virq, mpic);
set_irq_chip_and_handler(virq, chip, handle_fasteoi_irq);
/* Set default irq type */
set_irq_type(virq, IRQ_TYPE_NONE);
return 0;
}
static int mpic_host_xlate(struct irq_host *h, struct device_node *ct,
u32 *intspec, unsigned int intsize,
irq_hw_number_t *out_hwirq, unsigned int *out_flags)
{
static unsigned char map_mpic_senses[4] = {
IRQ_TYPE_EDGE_RISING,
IRQ_TYPE_LEVEL_LOW,
IRQ_TYPE_LEVEL_HIGH,
IRQ_TYPE_EDGE_FALLING,
};
*out_hwirq = intspec[0];
if (intsize > 1) {
u32 mask = 0x3;
/* Apple invented a new race of encoding on machines with
* an HT APIC. They encode, among others, the index within
* the HT APIC. We don't care about it here since thankfully,
* it appears that they have the APIC already properly
* configured, and thus our current fixup code that reads the
* APIC config works fine. However, we still need to mask out
* bits in the specifier to make sure we only get bit 0 which
* is the level/edge bit (the only sense bit exposed by Apple),
* as their bit 1 means something else.
*/
if (machine_is(powermac))
mask = 0x1;
*out_flags = map_mpic_senses[intspec[1] & mask];
} else
*out_flags = IRQ_TYPE_NONE;
DBG("mpic: xlate (%d cells: 0x%08x 0x%08x) to line 0x%lx sense 0x%x\n",
intsize, intspec[0], intspec[1], *out_hwirq, *out_flags);
return 0;
}
static struct irq_host_ops mpic_host_ops = {
.match = mpic_host_match,
.map = mpic_host_map,
.xlate = mpic_host_xlate,
};
/*
* Exported functions
*/
struct mpic * __init mpic_alloc(struct device_node *node,
unsigned long phys_addr,
unsigned int flags,
unsigned int isu_size,
unsigned int irq_count,
const char *name)
{
struct mpic *mpic;
u32 reg;
const char *vers;
int i;
mpic = alloc_bootmem(sizeof(struct mpic));
if (mpic == NULL)
return NULL;
memset(mpic, 0, sizeof(struct mpic));
mpic->name = name;
mpic->of_node = node ? of_node_get(node) : NULL;
mpic->irqhost = irq_alloc_host(IRQ_HOST_MAP_LINEAR, 256,
&mpic_host_ops,
MPIC_VEC_SPURRIOUS);
if (mpic->irqhost == NULL) {
of_node_put(node);
return NULL;
}
mpic->irqhost->host_data = mpic;
mpic->hc_irq = mpic_irq_chip;
mpic->hc_irq.typename = name;
if (flags & MPIC_PRIMARY)
mpic->hc_irq.set_affinity = mpic_set_affinity;
#ifdef CONFIG_MPIC_BROKEN_U3
mpic->hc_ht_irq = mpic_irq_ht_chip;
mpic->hc_ht_irq.typename = name;
if (flags & MPIC_PRIMARY)
mpic->hc_ht_irq.set_affinity = mpic_set_affinity;
#endif /* CONFIG_MPIC_BROKEN_U3 */
#ifdef CONFIG_SMP
mpic->hc_ipi = mpic_ipi_chip;
mpic->hc_ipi.typename = name;
#endif /* CONFIG_SMP */
mpic->flags = flags;
mpic->isu_size = isu_size;
mpic->irq_count = irq_count;
mpic->num_sources = 0; /* so far */
#ifdef CONFIG_MPIC_WEIRD
mpic->hw_set = mpic_infos[MPIC_GET_REGSET(flags)];
#endif
/* Map the global registers */
mpic->gregs = ioremap(phys_addr + MPIC_INFO(GREG_BASE), 0x1000);
mpic->tmregs = mpic->gregs +
((MPIC_INFO(TIMER_BASE) - MPIC_INFO(GREG_BASE)) >> 2);
BUG_ON(mpic->gregs == NULL);
/* Reset */
if (flags & MPIC_WANTS_RESET) {
mpic_write(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0),
mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
| MPIC_GREG_GCONF_RESET);
while( mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
& MPIC_GREG_GCONF_RESET)
mb();
}
/* Read feature register, calculate num CPUs and, for non-ISU
* MPICs, num sources as well. On ISU MPICs, sources are counted
* as ISUs are added
*/
reg = mpic_read(mpic->gregs, MPIC_INFO(GREG_FEATURE_0));
mpic->num_cpus = ((reg & MPIC_GREG_FEATURE_LAST_CPU_MASK)
>> MPIC_GREG_FEATURE_LAST_CPU_SHIFT) + 1;
if (isu_size == 0)
mpic->num_sources = ((reg & MPIC_GREG_FEATURE_LAST_SRC_MASK)
>> MPIC_GREG_FEATURE_LAST_SRC_SHIFT) + 1;
/* Map the per-CPU registers */
for (i = 0; i < mpic->num_cpus; i++) {
mpic->cpuregs[i] = ioremap(phys_addr + MPIC_INFO(CPU_BASE) +
i * MPIC_INFO(CPU_STRIDE), 0x1000);
BUG_ON(mpic->cpuregs[i] == NULL);
}
/* Initialize main ISU if none provided */
if (mpic->isu_size == 0) {
mpic->isu_size = mpic->num_sources;
mpic->isus[0] = ioremap(phys_addr + MPIC_INFO(IRQ_BASE),
MPIC_INFO(IRQ_STRIDE) * mpic->isu_size);
BUG_ON(mpic->isus[0] == NULL);
}
mpic->isu_shift = 1 + __ilog2(mpic->isu_size - 1);
mpic->isu_mask = (1 << mpic->isu_shift) - 1;
/* Display version */
switch (reg & MPIC_GREG_FEATURE_VERSION_MASK) {
case 1:
vers = "1.0";
break;
case 2:
vers = "1.2";
break;
case 3:
vers = "1.3";
break;
default:
vers = "<unknown>";
break;
}
printk(KERN_INFO "mpic: Setting up MPIC \"%s\" version %s at %lx, max %d CPUs\n",
name, vers, phys_addr, mpic->num_cpus);
printk(KERN_INFO "mpic: ISU size: %d, shift: %d, mask: %x\n", mpic->isu_size,
mpic->isu_shift, mpic->isu_mask);
mpic->next = mpics;
mpics = mpic;
if (flags & MPIC_PRIMARY) {
mpic_primary = mpic;
irq_set_default_host(mpic->irqhost);
}
return mpic;
}
void __init mpic_assign_isu(struct mpic *mpic, unsigned int isu_num,
unsigned long phys_addr)
{
unsigned int isu_first = isu_num * mpic->isu_size;
BUG_ON(isu_num >= MPIC_MAX_ISU);
mpic->isus[isu_num] = ioremap(phys_addr,
MPIC_INFO(IRQ_STRIDE) * mpic->isu_size);
if ((isu_first + mpic->isu_size) > mpic->num_sources)
mpic->num_sources = isu_first + mpic->isu_size;
}
void __init mpic_set_default_senses(struct mpic *mpic, u8 *senses, int count)
{
mpic->senses = senses;
mpic->senses_count = count;
}
void __init mpic_init(struct mpic *mpic)
{
int i;
BUG_ON(mpic->num_sources == 0);
WARN_ON(mpic->num_sources > MPIC_VEC_IPI_0);
/* Sanitize source count */
if (mpic->num_sources > MPIC_VEC_IPI_0)
mpic->num_sources = MPIC_VEC_IPI_0;
printk(KERN_INFO "mpic: Initializing for %d sources\n", mpic->num_sources);
/* Set current processor priority to max */
mpic_cpu_write(MPIC_INFO(CPU_CURRENT_TASK_PRI), 0xf);
/* Initialize timers: just disable them all */
for (i = 0; i < 4; i++) {
mpic_write(mpic->tmregs,
i * MPIC_INFO(TIMER_STRIDE) +
MPIC_INFO(TIMER_DESTINATION), 0);
mpic_write(mpic->tmregs,
i * MPIC_INFO(TIMER_STRIDE) +
MPIC_INFO(TIMER_VECTOR_PRI),
MPIC_VECPRI_MASK |
(MPIC_VEC_TIMER_0 + i));
}
/* Initialize IPIs to our reserved vectors and mark them disabled for now */
mpic_test_broken_ipi(mpic);
for (i = 0; i < 4; i++) {
mpic_ipi_write(i,
MPIC_VECPRI_MASK |
(10 << MPIC_VECPRI_PRIORITY_SHIFT) |
(MPIC_VEC_IPI_0 + i));
}
/* Initialize interrupt sources */
if (mpic->irq_count == 0)
mpic->irq_count = mpic->num_sources;
/* Do the HT PIC fixups on U3 broken mpic */
DBG("MPIC flags: %x\n", mpic->flags);
if ((mpic->flags & MPIC_BROKEN_U3) && (mpic->flags & MPIC_PRIMARY))
mpic_scan_ht_pics(mpic);
for (i = 0; i < mpic->num_sources; i++) {
/* start with vector = source number, and masked */
u32 vecpri = MPIC_VECPRI_MASK | i |
(8 << MPIC_VECPRI_PRIORITY_SHIFT);
/* init hw */
mpic_irq_write(i, MPIC_INFO(IRQ_VECTOR_PRI), vecpri);
mpic_irq_write(i, MPIC_INFO(IRQ_DESTINATION),
1 << hard_smp_processor_id());
}
/* Init spurrious vector */
mpic_write(mpic->gregs, MPIC_INFO(GREG_SPURIOUS), MPIC_VEC_SPURRIOUS);
/* Disable 8259 passthrough, if supported */
if (!(mpic->flags & MPIC_NO_PTHROU_DIS))
mpic_write(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0),
mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
| MPIC_GREG_GCONF_8259_PTHROU_DIS);
/* Set current processor priority to 0 */
mpic_cpu_write(MPIC_INFO(CPU_CURRENT_TASK_PRI), 0);
}
void __init mpic_set_clk_ratio(struct mpic *mpic, u32 clock_ratio)
{
u32 v;
v = mpic_read(mpic->gregs, MPIC_GREG_GLOBAL_CONF_1);
v &= ~MPIC_GREG_GLOBAL_CONF_1_CLK_RATIO_MASK;
v |= MPIC_GREG_GLOBAL_CONF_1_CLK_RATIO(clock_ratio);
mpic_write(mpic->gregs, MPIC_GREG_GLOBAL_CONF_1, v);
}
void __init mpic_set_serial_int(struct mpic *mpic, int enable)
{
unsigned long flags;
u32 v;
spin_lock_irqsave(&mpic_lock, flags);
v = mpic_read(mpic->gregs, MPIC_GREG_GLOBAL_CONF_1);
if (enable)
v |= MPIC_GREG_GLOBAL_CONF_1_SIE;
else
v &= ~MPIC_GREG_GLOBAL_CONF_1_SIE;
mpic_write(mpic->gregs, MPIC_GREG_GLOBAL_CONF_1, v);
spin_unlock_irqrestore(&mpic_lock, flags);
}
void mpic_irq_set_priority(unsigned int irq, unsigned int pri)
{
int is_ipi;
struct mpic *mpic = mpic_find(irq, &is_ipi);
unsigned int src = mpic_irq_to_hw(irq);
unsigned long flags;
u32 reg;
spin_lock_irqsave(&mpic_lock, flags);
if (is_ipi) {
reg = mpic_ipi_read(src - MPIC_VEC_IPI_0) &
~MPIC_VECPRI_PRIORITY_MASK;
mpic_ipi_write(src - MPIC_VEC_IPI_0,
reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
} else {
reg = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI))
& ~MPIC_VECPRI_PRIORITY_MASK;
mpic_irq_write(src, MPIC_INFO(IRQ_VECTOR_PRI),
reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
}
spin_unlock_irqrestore(&mpic_lock, flags);
}
unsigned int mpic_irq_get_priority(unsigned int irq)
{
int is_ipi;
struct mpic *mpic = mpic_find(irq, &is_ipi);
unsigned int src = mpic_irq_to_hw(irq);
unsigned long flags;
u32 reg;
spin_lock_irqsave(&mpic_lock, flags);
if (is_ipi)
reg = mpic_ipi_read(src = MPIC_VEC_IPI_0);
else
reg = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI));
spin_unlock_irqrestore(&mpic_lock, flags);
return (reg & MPIC_VECPRI_PRIORITY_MASK) >> MPIC_VECPRI_PRIORITY_SHIFT;
}
void mpic_setup_this_cpu(void)
{
#ifdef CONFIG_SMP
struct mpic *mpic = mpic_primary;
unsigned long flags;
u32 msk = 1 << hard_smp_processor_id();
unsigned int i;
BUG_ON(mpic == NULL);
DBG("%s: setup_this_cpu(%d)\n", mpic->name, hard_smp_processor_id());
spin_lock_irqsave(&mpic_lock, flags);
/* let the mpic know we want intrs. default affinity is 0xffffffff
* until changed via /proc. That's how it's done on x86. If we want
* it differently, then we should make sure we also change the default
* values of irq_desc[].affinity in irq.c.
*/
if (distribute_irqs) {
for (i = 0; i < mpic->num_sources ; i++)
mpic_irq_write(i, MPIC_INFO(IRQ_DESTINATION),
mpic_irq_read(i, MPIC_INFO(IRQ_DESTINATION)) | msk);
}
/* Set current processor priority to 0 */
mpic_cpu_write(MPIC_INFO(CPU_CURRENT_TASK_PRI), 0);
spin_unlock_irqrestore(&mpic_lock, flags);
#endif /* CONFIG_SMP */
}
int mpic_cpu_get_priority(void)
{
struct mpic *mpic = mpic_primary;
return mpic_cpu_read(MPIC_INFO(CPU_CURRENT_TASK_PRI));
}
void mpic_cpu_set_priority(int prio)
{
struct mpic *mpic = mpic_primary;
prio &= MPIC_CPU_TASKPRI_MASK;
mpic_cpu_write(MPIC_INFO(CPU_CURRENT_TASK_PRI), prio);
}
/*
* XXX: someone who knows mpic should check this.
* do we need to eoi the ipi including for kexec cpu here (see xics comments)?
* or can we reset the mpic in the new kernel?
*/
void mpic_teardown_this_cpu(int secondary)
{
struct mpic *mpic = mpic_primary;
unsigned long flags;
u32 msk = 1 << hard_smp_processor_id();
unsigned int i;
BUG_ON(mpic == NULL);
DBG("%s: teardown_this_cpu(%d)\n", mpic->name, hard_smp_processor_id());
spin_lock_irqsave(&mpic_lock, flags);
/* let the mpic know we don't want intrs. */
for (i = 0; i < mpic->num_sources ; i++)
mpic_irq_write(i, MPIC_INFO(IRQ_DESTINATION),
mpic_irq_read(i, MPIC_INFO(IRQ_DESTINATION)) & ~msk);
/* Set current processor priority to max */
mpic_cpu_write(MPIC_INFO(CPU_CURRENT_TASK_PRI), 0xf);
spin_unlock_irqrestore(&mpic_lock, flags);
}
void mpic_send_ipi(unsigned int ipi_no, unsigned int cpu_mask)
{
struct mpic *mpic = mpic_primary;
BUG_ON(mpic == NULL);
#ifdef DEBUG_IPI
DBG("%s: send_ipi(ipi_no: %d)\n", mpic->name, ipi_no);
#endif
mpic_cpu_write(MPIC_INFO(CPU_IPI_DISPATCH_0) +
ipi_no * MPIC_INFO(CPU_IPI_DISPATCH_STRIDE),
mpic_physmask(cpu_mask & cpus_addr(cpu_online_map)[0]));
}
unsigned int mpic_get_one_irq(struct mpic *mpic, struct pt_regs *regs)
{
u32 src;
src = mpic_cpu_read(MPIC_INFO(CPU_INTACK)) & MPIC_INFO(VECPRI_VECTOR_MASK);
#ifdef DEBUG_LOW
DBG("%s: get_one_irq(): %d\n", mpic->name, src);
#endif
if (unlikely(src == MPIC_VEC_SPURRIOUS))
return NO_IRQ;
return irq_linear_revmap(mpic->irqhost, src);
}
unsigned int mpic_get_irq(struct pt_regs *regs)
{
struct mpic *mpic = mpic_primary;
BUG_ON(mpic == NULL);
return mpic_get_one_irq(mpic, regs);
}
#ifdef CONFIG_SMP
void mpic_request_ipis(void)
{
struct mpic *mpic = mpic_primary;
int i;
static char *ipi_names[] = {
"IPI0 (call function)",
"IPI1 (reschedule)",
"IPI2 (unused)",
"IPI3 (debugger break)",
};
BUG_ON(mpic == NULL);
printk(KERN_INFO "mpic: requesting IPIs ... \n");
for (i = 0; i < 4; i++) {
unsigned int vipi = irq_create_mapping(mpic->irqhost,
MPIC_VEC_IPI_0 + i);
if (vipi == NO_IRQ) {
printk(KERN_ERR "Failed to map IPI %d\n", i);
break;
}
request_irq(vipi, mpic_ipi_action, IRQF_DISABLED,
ipi_names[i], mpic);
}
}
void smp_mpic_message_pass(int target, int msg)
{
/* make sure we're sending something that translates to an IPI */
if ((unsigned int)msg > 3) {
printk("SMP %d: smp_message_pass: unknown msg %d\n",
smp_processor_id(), msg);
return;
}
switch (target) {
case MSG_ALL:
mpic_send_ipi(msg, 0xffffffff);
break;
case MSG_ALL_BUT_SELF:
mpic_send_ipi(msg, 0xffffffff & ~(1 << smp_processor_id()));
break;
default:
mpic_send_ipi(msg, 1 << target);
break;
}
}
#endif /* CONFIG_SMP */