[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, 59 insertions, 29 deletions

diff --git a/arch/powerpc/platforms/maple/setup.c b/arch/powerpc/platforms/maple/setup.c
index 611ca8e979e5..cb528c9de4c3 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -198,50 +198,81 @@ static void __init maple_init_early(void)
 {
         DBG(" -> maple_init_early\n");
 
-        /* Setup interrupt mapping options */
-        ppc64_interrupt_controller = IC_OPEN_PIC;
-
         iommu_init_early_dart();
 
         DBG(" <- maple_init_early\n");
 }
 
-
-static __init void maple_init_IRQ(void)
+/*
+ * This is almost identical to pSeries and CHRP. We need to make that
+ * code generic at one point, with appropriate bits in the device-tree to
+ * identify the presence of an HT APIC
+ */
+static void __init maple_init_IRQ(void)
 {
-        struct device_node *root;
+        struct device_node *root, *np, *mpic_node = NULL;
         unsigned int *opprop;
-        unsigned long opic_addr;
+        unsigned long openpic_addr = 0;
+        int naddr, n, i, opplen, has_isus = 0;
         struct mpic *mpic;
-        unsigned char senses[128];
-        int n;
+        unsigned int flags = MPIC_PRIMARY;
 
-        DBG(" -> maple_init_IRQ\n");
+        /* Locate MPIC in the device-tree. Note that there is a bug
+         * in Maple device-tree where the type of the controller is
+         * open-pic and not interrupt-controller
+         */
+        for_each_node_by_type(np, "open-pic") {
+                mpic_node = np;
+                break;
+        }
+        if (mpic_node == NULL) {
+                printk(KERN_ERR
+                       "Failed to locate the MPIC interrupt controller\n");
+                return;
+        }
 
-        /* XXX: Non standard, replace that with a proper openpic/mpic node
-         * in the device-tree. Find the Open PIC if present */
+        /* Find address list in /platform-open-pic */
         root = of_find_node_by_path("/");
-        opprop = (unsigned int *) get_property(root,
-                                "platform-open-pic", NULL);
-        if (opprop == 0)
-                panic("OpenPIC not found !\n");
-
-        n = prom_n_addr_cells(root);
-        for (opic_addr = 0; n > 0; --n)
-                opic_addr = (opic_addr << 32) + *opprop++;
+        naddr = prom_n_addr_cells(root);
+        opprop = (unsigned int *) get_property(root, "platform-open-pic",
+                                               &opplen);
+        if (opprop != 0) {
+                openpic_addr = of_read_number(opprop, naddr);
+                has_isus = (opplen > naddr);
+                printk(KERN_DEBUG "OpenPIC addr: %lx, has ISUs: %d\n",
+                       openpic_addr, has_isus);
+        }
         of_node_put(root);
 
-        /* Obtain sense values from device-tree */
-        prom_get_irq_senses(senses, 0, 128);
+        BUG_ON(openpic_addr == 0);
 
-        mpic = mpic_alloc(opic_addr,
-                          MPIC_PRIMARY | MPIC_BIG_ENDIAN |
-                          MPIC_BROKEN_U3 | MPIC_WANTS_RESET,
-                          0, 0, 128, 128, senses, 128, "U3-MPIC");
+        /* Check for a big endian MPIC */
+        if (get_property(np, "big-endian", NULL) != NULL)
+                flags |= MPIC_BIG_ENDIAN;
+
+        /* XXX Maple specific bits */
+        flags |= MPIC_BROKEN_U3 | MPIC_WANTS_RESET;
+
+        /* Setup the openpic driver. More device-tree junks, we hard code no
+         * ISUs for now. I'll have to revisit some stuffs with the folks doing
+         * the firmware for those
+         */
+        mpic = mpic_alloc(mpic_node, openpic_addr, flags,
+                          /*has_isus ? 16 :*/ 0, 0, " MPIC     ");
         BUG_ON(mpic == NULL);
-        mpic_init(mpic);
 
-        DBG(" <- maple_init_IRQ\n");
+        /* Add ISUs */
+        opplen /= sizeof(u32);
+        for (n = 0, i = naddr; i < opplen; i += naddr, n++) {
+                unsigned long isuaddr = of_read_number(opprop + i, naddr);
+                mpic_assign_isu(mpic, n, isuaddr);
+        }
+
+        /* All ISUs are setup, complete initialization */
+        mpic_init(mpic);
+        ppc_md.get_irq = mpic_get_irq;
+        of_node_put(mpic_node);
+        of_node_put(root);
 }
 
 static void __init maple_progress(char *s, unsigned short hex)
@@ -279,7 +310,6 @@ define_machine(maple_md) {
         .setup_arch             = maple_setup_arch,
         .init_early             = maple_init_early,
         .init_IRQ               = maple_init_IRQ,
-        .get_irq                = mpic_get_irq,
         .pcibios_fixup          = maple_pcibios_fixup,
         .pci_get_legacy_ide_irq = maple_pci_get_legacy_ide_irq,
         .restart                = maple_restart,