mpic.c

来自「linux 内核源代码」· C语言 代码 · 共 1,607 行 · 第 1/3 页

/*
 *  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>

#include "mpic.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(enum mpic_reg_type type,
			     struct mpic_reg_bank *rb,
			     unsigned int reg)
{
	switch(type) {
#ifdef CONFIG_PPC_DCR
	case mpic_access_dcr:
		return dcr_read(rb->dhost, reg);
#endif
	case mpic_access_mmio_be:
		return in_be32(rb->base + (reg >> 2));
	case mpic_access_mmio_le:
	default:
		return in_le32(rb->base + (reg >> 2));
	}
}

static inline void _mpic_write(enum mpic_reg_type type,
			       struct mpic_reg_bank *rb,
 			       unsigned int reg, u32 value)
{
	switch(type) {
#ifdef CONFIG_PPC_DCR
	case mpic_access_dcr:
		return dcr_write(rb->dhost, reg, value);
#endif
	case mpic_access_mmio_be:
		return out_be32(rb->base + (reg >> 2), value);
	case mpic_access_mmio_le:
	default:
		return out_le32(rb->base + (reg >> 2), value);
	}
}

static inline u32 _mpic_ipi_read(struct mpic *mpic, unsigned int ipi)
{
	enum mpic_reg_type type = mpic->reg_type;
	unsigned int offset = MPIC_INFO(GREG_IPI_VECTOR_PRI_0) +
			      (ipi * MPIC_INFO(GREG_IPI_STRIDE));

	if ((mpic->flags & MPIC_BROKEN_IPI) && type == mpic_access_mmio_le)
		type = mpic_access_mmio_be;
	return _mpic_read(type, &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->reg_type, &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->reg_type, &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->reg_type, &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;

#ifdef CONFIG_MPIC_BROKEN_REGREAD
	if (reg == 0)
		return mpic->isu_reg0_shadow[idx];
	else
#endif
		return _mpic_read(mpic->reg_type, &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->reg_type, &mpic->isus[isu],
		    reg + (idx * MPIC_INFO(IRQ_STRIDE)), value);

#ifdef CONFIG_MPIC_BROKEN_REGREAD
	if (reg == 0)
		mpic->isu_reg0_shadow[idx] = value;
#endif
}

#define mpic_read(b,r)		_mpic_read(mpic->reg_type,&(b),(r))
#define mpic_write(b,r,v)	_mpic_write(mpic->reg_type,&(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
 */


static void _mpic_map_mmio(struct mpic *mpic, unsigned long phys_addr,
			   struct mpic_reg_bank *rb, unsigned int offset,
			   unsigned int size)
{
	rb->base = ioremap(phys_addr + offset, size);
	BUG_ON(rb->base == NULL);
}

#ifdef CONFIG_PPC_DCR
static void _mpic_map_dcr(struct mpic *mpic, struct mpic_reg_bank *rb,
			  unsigned int offset, unsigned int size)
{
	const u32 *dbasep;

	dbasep = of_get_property(mpic->irqhost->of_node, "dcr-reg", NULL);

	rb->dhost = dcr_map(mpic->irqhost->of_node, *dbasep + offset, size);
	BUG_ON(!DCR_MAP_OK(rb->dhost));
}

static inline void mpic_map(struct mpic *mpic, unsigned long phys_addr,
			    struct mpic_reg_bank *rb, unsigned int offset,
			    unsigned int size)
{
	if (mpic->flags & MPIC_USES_DCR)
		_mpic_map_dcr(mpic, rb, offset, size);
	else
		_mpic_map_mmio(mpic, phys_addr, rb, offset, size);
}
#else /* CONFIG_PPC_DCR */
#define mpic_map(m,p,b,o,s)	_mpic_map_mmio(m,p,b,o,s)
#endif /* !CONFIG_PPC_DCR */



/* 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_U3_HT_IRQS

/* 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);

#ifdef CONFIG_PM
	/* use the lowest bit inverted to the actual HW,
	 * set if this fixup was enabled, clear otherwise */
	mpic->save_data[source].fixup_data = tmp | 1;
#endif
}

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);

#ifdef CONFIG_PM
	/* use the lowest bit inverted to the actual HW,
	 * set if this fixup was enabled, clear otherwise */
	mpic->save_data[source].fixup_data = tmp & ~1;
#endif
}

#ifdef CONFIG_PCI_MSI
static void __init mpic_scan_ht_msi(struct mpic *mpic, u8 __iomem *devbase,
				    unsigned int devfn)
{
	u8 __iomem *base;
	u8 pos, flags;
	u64 addr = 0;

	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_5BIT_CAP_MASK) == HT_CAPTYPE_MSI_MAPPING)
				break;
		}
	}

	if (pos == 0)
		return;

	base = devbase + pos;

	flags = readb(base + HT_MSI_FLAGS);
	if (!(flags & HT_MSI_FLAGS_FIXED)) {
		addr = readl(base + HT_MSI_ADDR_LO) & HT_MSI_ADDR_LO_MASK;
		addr = addr | ((u64)readl(base + HT_MSI_ADDR_HI) << 32);
	}

	printk(KERN_DEBUG "mpic:   - HT:%02x.%x %s MSI mapping found @ 0x%lx\n",
		PCI_SLOT(devfn), PCI_FUNC(devfn),
		flags & HT_MSI_FLAGS_ENABLE ? "enabled" : "disabled", addr);

	if (!(flags & HT_MSI_FLAGS_ENABLE))
		writeb(flags | HT_MSI_FLAGS_ENABLE, base + HT_MSI_FLAGS);
}
#else
static void __init mpic_scan_ht_msi(struct mpic *mpic, u8 __iomem *devbase,
				    unsigned int devfn)
{
	return;
}
#endif

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_5BIT_CAP_MASK) == 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;