[POWERPC] Add new interrupt mapping core and change platforms to use it

This adds the new irq remapper core and removes the old one.  Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).

This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.

For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259.  That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.

The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 2 insertions, 449 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index ef3619c28702..a1787ffb6319 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -30,6 +30,7 @@
 #include <linux/module.h>
 #include <linux/kexec.h>
 #include <linux/debugfs.h>
+#include <linux/irq.h>
 
 #include <asm/prom.h>
 #include <asm/rtas.h>
@@ -86,424 +87,6 @@ static DEFINE_RWLOCK(devtree_lock);
 /* export that to outside world */
 struct device_node *of_chosen;
 
-struct device_node *dflt_interrupt_controller;
-int num_interrupt_controllers;
-
-/*
- * Wrapper for allocating memory for various data that needs to be
- * attached to device nodes as they are processed at boot or when
- * added to the device tree later (e.g. DLPAR).  At boot there is
- * already a region reserved so we just increment *mem_start by size;
- * otherwise we call kmalloc.
- */
-static void * prom_alloc(unsigned long size, unsigned long *mem_start)
-{
-        unsigned long tmp;
-
-        if (!mem_start)
-                return kmalloc(size, GFP_KERNEL);
-
-        tmp = *mem_start;
-        *mem_start += size;
-        return (void *)tmp;
-}
-
-/*
- * Find the device_node with a given phandle.
- */
-static struct device_node * find_phandle(phandle ph)
-{
-        struct device_node *np;
-
-        for (np = allnodes; np != 0; np = np->allnext)
-                if (np->linux_phandle == ph)
-                        return np;
-        return NULL;
-}
-
-/*
- * Find the interrupt parent of a node.
- */
-static struct device_node * __devinit intr_parent(struct device_node *p)
-{
-        phandle *parp;
-
-        parp = (phandle *) get_property(p, "interrupt-parent", NULL);
-        if (parp == NULL)
-                return p->parent;
-        p = find_phandle(*parp);
-        if (p != NULL)
-                return p;
-        /*
-         * On a powermac booted with BootX, we don't get to know the
-         * phandles for any nodes, so find_phandle will return NULL.
-         * Fortunately these machines only have one interrupt controller
-         * so there isn't in fact any ambiguity.  -- paulus
-         */
-        if (num_interrupt_controllers == 1)
-                p = dflt_interrupt_controller;
-        return p;
-}
-
-/*
- * Find out the size of each entry of the interrupts property
- * for a node.
- */
-int __devinit prom_n_intr_cells(struct device_node *np)
-{
-        struct device_node *p;
-        unsigned int *icp;
-
-        for (p = np; (p = intr_parent(p)) != NULL; ) {
-                icp = (unsigned int *)
-                        get_property(p, "#interrupt-cells", NULL);
-                if (icp != NULL)
-                        return *icp;
-                if (get_property(p, "interrupt-controller", NULL) != NULL
-                    || get_property(p, "interrupt-map", NULL) != NULL) {
-                        printk("oops, node %s doesn't have #interrupt-cells\n",
-                               p->full_name);
-                        return 1;
-                }
-        }
-#ifdef DEBUG_IRQ
-        printk("prom_n_intr_cells failed for %s\n", np->full_name);
-#endif
-        return 1;
-}
-
-/*
- * Map an interrupt from a device up to the platform interrupt
- * descriptor.
- */
-static int __devinit map_interrupt(unsigned int **irq, struct device_node **ictrler,
-                                   struct device_node *np, unsigned int *ints,
-                                   int nintrc)
-{
-        struct device_node *p, *ipar;
-        unsigned int *imap, *imask, *ip;
-        int i, imaplen, match;
-        int newintrc = 0, newaddrc = 0;
-        unsigned int *reg;
-        int naddrc;
-
-        reg = (unsigned int *) get_property(np, "reg", NULL);
-        naddrc = prom_n_addr_cells(np);
-        p = intr_parent(np);
-        while (p != NULL) {
-                if (get_property(p, "interrupt-controller", NULL) != NULL)
-                        /* this node is an interrupt controller, stop here */
-                        break;
-                imap = (unsigned int *)
-                        get_property(p, "interrupt-map", &imaplen);
-                if (imap == NULL) {
-                        p = intr_parent(p);
-                        continue;
-                }
-                imask = (unsigned int *)
-                        get_property(p, "interrupt-map-mask", NULL);
-                if (imask == NULL) {
-                        printk("oops, %s has interrupt-map but no mask\n",
-                               p->full_name);
-                        return 0;
-                }
-                imaplen /= sizeof(unsigned int);
-                match = 0;
-                ipar = NULL;
-                while (imaplen > 0 && !match) {
-                        /* check the child-interrupt field */
-                        match = 1;
-                        for (i = 0; i < naddrc && match; ++i)
-                                match = ((reg[i] ^ imap[i]) & imask[i]) == 0;
-                        for (; i < naddrc + nintrc && match; ++i)
-                                match = ((ints[i-naddrc] ^ imap[i]) & imask[i]) == 0;
-                        imap += naddrc + nintrc;
-                        imaplen -= naddrc + nintrc;
-                        /* grab the interrupt parent */
-                        ipar = find_phandle((phandle) *imap++);
-                        --imaplen;
-                        if (ipar == NULL && num_interrupt_controllers == 1)
-                                /* cope with BootX not giving us phandles */
-                                ipar = dflt_interrupt_controller;
-                        if (ipar == NULL) {
-                                printk("oops, no int parent %x in map of %s\n",
-                                       imap[-1], p->full_name);
-                                return 0;
-                        }
-                        /* find the parent's # addr and intr cells */
-                        ip = (unsigned int *)
-                                get_property(ipar, "#interrupt-cells", NULL);
-                        if (ip == NULL) {
-                                printk("oops, no #interrupt-cells on %s\n",
-                                       ipar->full_name);
-                                return 0;
-                        }
-                        newintrc = *ip;
-                        ip = (unsigned int *)
-                                get_property(ipar, "#address-cells", NULL);
-                        newaddrc = (ip == NULL)? 0: *ip;
-                        imap += newaddrc + newintrc;
-                        imaplen -= newaddrc + newintrc;
-                }
-                if (imaplen < 0) {
-                        printk("oops, error decoding int-map on %s, len=%d\n",
-                               p->full_name, imaplen);
-                        return 0;
-                }
-                if (!match) {
-#ifdef DEBUG_IRQ
-                        printk("oops, no match in %s int-map for %s\n",
-                               p->full_name, np->full_name);
-#endif
-                        return 0;
-                }
-                p = ipar;
-                naddrc = newaddrc;
-                nintrc = newintrc;
-                ints = imap - nintrc;
-                reg = ints - naddrc;
-        }
-        if (p == NULL) {
-#ifdef DEBUG_IRQ
-                printk("hmmm, int tree for %s doesn't have ctrler\n",
-                       np->full_name);
-#endif
-                return 0;
-        }
-        *irq = ints;
-        *ictrler = p;
-        return nintrc;
-}
-
-static unsigned char map_isa_senses[4] = {
-        IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE,
-        IRQ_SENSE_LEVEL | IRQ_POLARITY_POSITIVE,
-        IRQ_SENSE_EDGE  | IRQ_POLARITY_NEGATIVE,
-        IRQ_SENSE_EDGE  | IRQ_POLARITY_POSITIVE
-};
-
-static unsigned char map_mpic_senses[4] = {
-        IRQ_SENSE_EDGE  | IRQ_POLARITY_POSITIVE,
-        IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE,
-        /* 2 seems to be used for the 8259 cascade... */
-        IRQ_SENSE_LEVEL | IRQ_POLARITY_POSITIVE,
-        IRQ_SENSE_EDGE  | IRQ_POLARITY_NEGATIVE,
-};
-
-static int __devinit finish_node_interrupts(struct device_node *np,
-                                            unsigned long *mem_start,
-                                            int measure_only)
-{
-        unsigned int *ints;
-        int intlen, intrcells, intrcount;
-        int i, j, n, sense;
-        unsigned int *irq, virq;
-        struct device_node *ic;
-        int trace = 0;
-
-        //#define TRACE(fmt...) do { if (trace) { printk(fmt); mdelay(1000); } } while(0)
-#define TRACE(fmt...)
-
-        if (!strcmp(np->name, "smu-doorbell"))
-                trace = 1;
-
-        TRACE("Finishing SMU doorbell ! num_interrupt_controllers = %d\n",
-              num_interrupt_controllers);
-
-        if (num_interrupt_controllers == 0) {
-                /*
-                 * Old machines just have a list of interrupt numbers
-                 * and no interrupt-controller nodes.
-                 */
-                ints = (unsigned int *) get_property(np, "AAPL,interrupts",
-                                                     &intlen);
-                /* XXX old interpret_pci_props looked in parent too */
-                /* XXX old interpret_macio_props looked for interrupts
-                   before AAPL,interrupts */
-                if (ints == NULL)
-                        ints = (unsigned int *) get_property(np, "interrupts",
-                                                             &intlen);
-                if (ints == NULL)
-                        return 0;
-
-                np->n_intrs = intlen / sizeof(unsigned int);
-                np->intrs = prom_alloc(np->n_intrs * sizeof(np->intrs[0]),
-                                       mem_start);
-                if (!np->intrs)
-                        return -ENOMEM;
-                if (measure_only)
-                        return 0;
-
-                for (i = 0; i < np->n_intrs; ++i) {
-                        np->intrs[i].line = *ints++;
-                        np->intrs[i].sense = IRQ_SENSE_LEVEL
-                                | IRQ_POLARITY_NEGATIVE;
-                }
-                return 0;
-        }
-
-        ints = (unsigned int *) get_property(np, "interrupts", &intlen);
-        TRACE("ints=%p, intlen=%d\n", ints, intlen);
-        if (ints == NULL)
-                return 0;
-        intrcells = prom_n_intr_cells(np);
-        intlen /= intrcells * sizeof(unsigned int);
-        TRACE("intrcells=%d, new intlen=%d\n", intrcells, intlen);
-        np->intrs = prom_alloc(intlen * sizeof(*(np->intrs)), mem_start);
-        if (!np->intrs)
-                return -ENOMEM;
-
-        if (measure_only)
-                return 0;
-
-        intrcount = 0;
-        for (i = 0; i < intlen; ++i, ints += intrcells) {
-                n = map_interrupt(&irq, &ic, np, ints, intrcells);
-                TRACE("map, irq=%d, ic=%p, n=%d\n", irq, ic, n);
-                if (n <= 0)
-                        continue;
-
-                /* don't map IRQ numbers under a cascaded 8259 controller */
-                if (ic && device_is_compatible(ic, "chrp,iic")) {
-                        np->intrs[intrcount].line = irq[0];
-                        sense = (n > 1)? (irq[1] & 3): 3;
-                        np->intrs[intrcount].sense = map_isa_senses[sense];
-                } else {
-                        virq = virt_irq_create_mapping(irq[0]);
-                        TRACE("virq=%d\n", virq);
-#ifdef CONFIG_PPC64
-                        if (virq == NO_IRQ) {
-                                printk(KERN_CRIT "Could not allocate interrupt"
-                                       " number for %s\n", np->full_name);
-                                continue;
-                        }
-#endif
-                        np->intrs[intrcount].line = irq_offset_up(virq);
-                        sense = (n > 1)? (irq[1] & 3): 1;
-
-                        /* Apple uses bits in there in a different way, let's
-                         * only keep the real sense bit on macs
-                         */
-                        if (machine_is(powermac))
-                                sense &= 0x1;
-                        np->intrs[intrcount].sense = map_mpic_senses[sense];
-                }
-
-#ifdef CONFIG_PPC64
-                /* We offset irq numbers for the u3 MPIC by 128 in PowerMac */
-                if (machine_is(powermac) && ic && ic->parent) {
-                        char *name = get_property(ic->parent, "name", NULL);
-                        if (name && !strcmp(name, "u3"))
-                                np->intrs[intrcount].line += 128;
-                        else if (!(name && (!strcmp(name, "mac-io") ||
-                                            !strcmp(name, "u4"))))
-                                /* ignore other cascaded controllers, such as
-                                   the k2-sata-root */
-                                break;
-                }
-#endif /* CONFIG_PPC64 */
-                if (n > 2) {
-                        printk("hmmm, got %d intr cells for %s:", n,
-                               np->full_name);
-                        for (j = 0; j < n; ++j)
-                                printk(" %d", irq[j]);
-                        printk("\n");
-                }
-                ++intrcount;
-        }
-        np->n_intrs = intrcount;
-
-        return 0;
-}
-
-static int __devinit finish_node(struct device_node *np,
-                                 unsigned long *mem_start,
-                                 int measure_only)
-{
-        struct device_node *child;
-        int rc = 0;
-
-        rc = finish_node_interrupts(np, mem_start, measure_only);
-        if (rc)
-                goto out;
-
-        for (child = np->child; child != NULL; child = child->sibling) {
-                rc = finish_node(child, mem_start, measure_only);
-                if (rc)
-                        goto out;
-        }
-out:
-        return rc;
-}
-
-static void __init scan_interrupt_controllers(void)
-{
-        struct device_node *np;
-        int n = 0;
-        char *name, *ic;
-        int iclen;
-
-        for (np = allnodes; np != NULL; np = np->allnext) {
-                ic = get_property(np, "interrupt-controller", &iclen);
-                name = get_property(np, "name", NULL);
-                /* checking iclen makes sure we don't get a false
-                   match on /chosen.interrupt_controller */
-                if ((name != NULL
-                     && strcmp(name, "interrupt-controller") == 0)
-                    || (ic != NULL && iclen == 0
-                        && strcmp(name, "AppleKiwi"))) {
-                        if (n == 0)
-                                dflt_interrupt_controller = np;
-                        ++n;
-                }
-        }
-        num_interrupt_controllers = n;
-}
-
-/**
- * finish_device_tree is called once things are running normally
- * (i.e. with text and data mapped to the address they were linked at).
- * It traverses the device tree and fills in some of the additional,
- * fields in each node like {n_}addrs and {n_}intrs, the virt interrupt
- * mapping is also initialized at this point.
- */
-void __init finish_device_tree(void)
-{
-        unsigned long start, end, size = 0;
-
-        DBG(" -> finish_device_tree\n");
-
-#ifdef CONFIG_PPC64
-        /* Initialize virtual IRQ map */
-        virt_irq_init();
-#endif
-        scan_interrupt_controllers();
-
-        /*
-         * Finish device-tree (pre-parsing some properties etc...)
-         * We do this in 2 passes. One with "measure_only" set, which
-         * will only measure the amount of memory needed, then we can
-         * allocate that memory, and call finish_node again. However,
-         * we must be careful as most routines will fail nowadays when
-         * prom_alloc() returns 0, so we must make sure our first pass
-         * doesn't start at 0. We pre-initialize size to 16 for that
-         * reason and then remove those additional 16 bytes
-         */
-        size = 16;
-        finish_node(allnodes, &size, 1);
-        size -= 16;
-
-        if (0 == size)
-                end = start = 0;
-        else
-                end = start = (unsigned long)__va(lmb_alloc(size, 128));
-
-        finish_node(allnodes, &end, 0);
-        BUG_ON(end != start + size);
-
-        DBG(" <- finish_device_tree\n");
-}
-
 static inline char *find_flat_dt_string(u32 offset)
 {
         return ((char *)initial_boot_params) +
@@ -1389,27 +972,6 @@ prom_n_size_cells(struct device_node* np)
 EXPORT_SYMBOL(prom_n_size_cells);
 
 /**
- * Work out the sense (active-low level / active-high edge)
- * of each interrupt from the device tree.
- */
-void __init prom_get_irq_senses(unsigned char *senses, int off, int max)
-{
-        struct device_node *np;
-        int i, j;
-
-        /* default to level-triggered */
-        memset(senses, IRQ_SENSE_LEVEL | IRQ_POLARITY_NEGATIVE, max - off);
-
-        for (np = allnodes; np != 0; np = np->allnext) {
-                for (j = 0; j < np->n_intrs; j++) {
-                        i = np->intrs[j].line;
-                        if (i >= off && i < max)
-                                senses[i-off] = np->intrs[j].sense;
-                }
-        }
-}
-
-/**
  * Construct and return a list of the device_nodes with a given name.
  */
 struct device_node *find_devices(const char *name)
@@ -1808,7 +1370,6 @@ static void of_node_release(struct kref *kref)
                         node->deadprops = NULL;
                 }
         }
-        kfree(node->intrs);
         kfree(node->full_name);
         kfree(node->data);
         kfree(node);
@@ -1881,13 +1442,7 @@ void of_detach_node(const struct device_node *np)
 #ifdef CONFIG_PPC_PSERIES
 /*
  * Fix up the uninitialized fields in a new device node:
- * name, type, n_addrs, addrs, n_intrs, intrs, and pci-specific fields
- *
- * A lot of boot-time code is duplicated here, because functions such
- * as finish_node_interrupts, interpret_pci_props, etc. cannot use the
- * slab allocator.
- *
- * This should probably be split up into smaller chunks.
+ * name, type and pci-specific fields
  */
 
 static int of_finish_dynamic_node(struct device_node *node)
@@ -1928,8 +1483,6 @@ static int prom_reconfig_notifier(struct notifier_block *nb,
         switch (action) {
         case PSERIES_RECONFIG_ADD:
                 err = of_finish_dynamic_node(node);
-                if (!err)
-                        finish_node(node, NULL, 0);
                 if (err < 0) {
                         printk(KERN_ERR "finish_node returned %d\n", err);
                         err = NOTIFY_BAD;