1 files changed, 271 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/isa-bridge.c b/arch/powerpc/kernel/isa-bridge.c
new file mode 100644
index 000000000000..f0f49d1be3d5
--- /dev/null
+++ b/arch/powerpc/kernel/isa-bridge.c
@@ -0,0 +1,271 @@
+/*
+ * Routines for tracking a legacy ISA bridge
+ *
+ * Copyrigh 2007 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
+ *
+ * Some bits and pieces moved over from pci_64.c
+ *
+ * Copyrigh 2003 Anton Blanchard <anton@au.ibm.com>, IBM Corp.
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#define DEBUG
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/notifier.h>
+
+#include <asm/processor.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/pci-bridge.h>
+#include <asm/machdep.h>
+#include <asm/ppc-pci.h>
+#include <asm/firmware.h>
+
+unsigned long isa_io_base;      /* NULL if no ISA bus */
+EXPORT_SYMBOL(isa_io_base);
+
+/* Cached ISA bridge dev. */
+static struct device_node *isa_bridge_devnode;
+struct pci_dev *isa_bridge_pcidev;
+EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
+
+#define ISA_SPACE_MASK 0x1
+#define ISA_SPACE_IO 0x1
+
+static void __devinit pci_process_ISA_OF_ranges(struct device_node *isa_node,
+                                                unsigned long phb_io_base_phys)
+{
+        /* We should get some saner parsing here and remove these structs */
+        struct pci_address {
+                u32 a_hi;
+                u32 a_mid;
+                u32 a_lo;
+        };
+
+        struct isa_address {
+                u32 a_hi;
+                u32 a_lo;
+        };
+
+        struct isa_range {
+                struct isa_address isa_addr;
+                struct pci_address pci_addr;
+                unsigned int size;
+        };
+
+        const struct isa_range *range;
+        unsigned long pci_addr;
+        unsigned int isa_addr;
+        unsigned int size;
+        int rlen = 0;
+
+        range = of_get_property(isa_node, "ranges", &rlen);
+        if (range == NULL || (rlen < sizeof(struct isa_range)))
+                goto inval_range;
+
+        /* From "ISA Binding to 1275"
+         * The ranges property is laid out as an array of elements,
+         * each of which comprises:
+         *   cells 0 - 1:       an ISA address
+         *   cells 2 - 4:       a PCI address
+         *                      (size depending on dev->n_addr_cells)
+         *   cell 5:            the size of the range
+         */
+        if ((range->isa_addr.a_hi && ISA_SPACE_MASK) != ISA_SPACE_IO) {
+                range++;
+                rlen -= sizeof(struct isa_range);
+                if (rlen < sizeof(struct isa_range))
+                        goto inval_range;
+        }
+        if ((range->isa_addr.a_hi && ISA_SPACE_MASK) != ISA_SPACE_IO)
+                goto inval_range;
+
+        isa_addr = range->isa_addr.a_lo;
+        pci_addr = (unsigned long) range->pci_addr.a_mid << 32 |
+                range->pci_addr.a_lo;
+
+        /* Assume these are both zero. Note: We could fix that and
+         * do a proper parsing instead ... oh well, that will do for
+         * now as nobody uses fancy mappings for ISA bridges
+         */
+        if ((pci_addr != 0) || (isa_addr != 0)) {
+                printk(KERN_ERR "unexpected isa to pci mapping: %s\n",
+                       __FUNCTION__);
+                return;
+        }
+
+        /* Align size and make sure it's cropped to 64K */
+        size = PAGE_ALIGN(range->size);
+        if (size > 0x10000)
+                size = 0x10000;
+
+        printk(KERN_ERR "no ISA IO ranges or unexpected isa range,"
+               "mapping 64k\n");
+
+        __ioremap_at(phb_io_base_phys, (void *)ISA_IO_BASE,
+                     size, _PAGE_NO_CACHE|_PAGE_GUARDED);
+        return;
+
+inval_range:
+        printk(KERN_ERR "no ISA IO ranges or unexpected isa range,"
+               "mapping 64k\n");
+        __ioremap_at(phb_io_base_phys, (void *)ISA_IO_BASE,
+                     0x10000, _PAGE_NO_CACHE|_PAGE_GUARDED);
+}
+
+
+/**
+ * isa_bridge_find_early - Find and map the ISA IO space early before
+ *                         main PCI discovery. This is optionally called by
+ *                         the arch code when adding PCI PHBs to get early
+ *                         access to ISA IO ports
+ */
+void __init isa_bridge_find_early(struct pci_controller *hose)
+{
+        struct device_node *np, *parent = NULL, *tmp;
+
+        /* If we already have an ISA bridge, bail off */
+        if (isa_bridge_devnode != NULL)
+                return;
+
+        /* For each "isa" node in the system. Note : we do a search by
+         * type and not by name. It might be better to do by name but that's
+         * what the code used to do and I don't want to break too much at
+         * once. We can look into changing that separately
+         */
+        for_each_node_by_type(np, "isa") {
+                /* Look for our hose being a parent */
+                for (parent = of_get_parent(np); parent;) {
+                        if (parent == hose->arch_data) {
+                                of_node_put(parent);
+                                break;
+                        }
+                        tmp = parent;
+                        parent = of_get_parent(parent);
+                        of_node_put(tmp);
+                }
+                if (parent != NULL)
+                        break;
+        }
+        if (np == NULL)
+                return;
+        isa_bridge_devnode = np;
+
+        /* Now parse the "ranges" property and setup the ISA mapping */
+        pci_process_ISA_OF_ranges(np, hose->io_base_phys);
+
+        /* Set the global ISA io base to indicate we have an ISA bridge */
+        isa_io_base = ISA_IO_BASE;
+
+        pr_debug("ISA bridge (early) is %s\n", np->full_name);
+}
+
+/**
+ * isa_bridge_find_late - Find and map the ISA IO space upon discovery of
+ *                        a new ISA bridge
+ */
+static void __devinit isa_bridge_find_late(struct pci_dev *pdev,
+                                           struct device_node *devnode)
+{
+        struct pci_controller *hose = pci_bus_to_host(pdev->bus);
+
+        /* Store ISA device node and PCI device */
+        isa_bridge_devnode = of_node_get(devnode);
+        isa_bridge_pcidev = pdev;
+
+        /* Now parse the "ranges" property and setup the ISA mapping */
+        pci_process_ISA_OF_ranges(devnode, hose->io_base_phys);
+
+        /* Set the global ISA io base to indicate we have an ISA bridge */
+        isa_io_base = ISA_IO_BASE;
+
+        pr_debug("ISA bridge (late) is %s on %s\n",
+                 devnode->full_name, pci_name(pdev));
+}
+
+/**
+ * isa_bridge_remove - Remove/unmap an ISA bridge
+ */
+static void isa_bridge_remove(void)
+{
+        pr_debug("ISA bridge removed !\n");
+
+        /* Clear the global ISA io base to indicate that we have no more
+         * ISA bridge. Note that drivers don't quite handle that, though
+         * we should probably do something about it. But do we ever really
+         * have ISA bridges being removed on machines using legacy devices ?
+         */
+        isa_io_base = ISA_IO_BASE;
+
+        /* Clear references to the bridge */
+        of_node_put(isa_bridge_devnode);
+        isa_bridge_devnode = NULL;
+        isa_bridge_pcidev = NULL;
+
+        /* Unmap the ISA area */
+        __iounmap_at((void *)ISA_IO_BASE, 0x10000);
+}
+
+/**
+ * isa_bridge_notify - Get notified of PCI devices addition/removal
+ */
+static int __devinit isa_bridge_notify(struct notifier_block *nb,
+                                       unsigned long action, void *data)
+{
+        struct device *dev = data;
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct device_node *devnode = pci_device_to_OF_node(pdev);
+
+        switch(action) {
+        case BUS_NOTIFY_ADD_DEVICE:
+                /* Check if we have an early ISA device, without PCI dev */
+                if (isa_bridge_devnode && isa_bridge_devnode == devnode &&
+                    !isa_bridge_pcidev) {
+                        pr_debug("ISA bridge PCI attached: %s\n",
+                                 pci_name(pdev));
+                        isa_bridge_pcidev = pdev;
+                }
+
+                /* Check if we have no ISA device, and this happens to be one,
+                 * register it as such if it has an OF device
+                 */
+                if (!isa_bridge_devnode && devnode && devnode->type &&
+                    !strcmp(devnode->type, "isa"))
+                        isa_bridge_find_late(pdev, devnode);
+
+                return 0;
+        case BUS_NOTIFY_DEL_DEVICE:
+                /* Check if this our existing ISA device */
+                if (pdev == isa_bridge_pcidev ||
+                    (devnode && devnode == isa_bridge_devnode))
+                        isa_bridge_remove();
+                return 0;
+        }
+        return 0;
+}
+
+static struct notifier_block isa_bridge_notifier = {
+        .notifier_call = isa_bridge_notify
+};
+
+/**
+ * isa_bridge_init - register to be notified of ISA bridge addition/removal
+ *
+ */
+static int __init isa_bridge_init(void)
+{
+        if (firmware_has_feature(FW_FEATURE_ISERIES))
+                return 0;
+        bus_register_notifier(&pci_bus_type, &isa_bridge_notifier);
+        return 0;
+}
+arch_initcall(isa_bridge_init);