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-rw-r--r--arch/powerpc/kernel/isa-bridge.c358
1 files changed, 358 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/isa-bridge.c b/arch/powerpc/kernel/isa-bridge.c
new file mode 100644
index 000000000..1df6c74aa
--- /dev/null
+++ b/arch/powerpc/kernel/isa-bridge.c
@@ -0,0 +1,358 @@
+/*
+ * 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/export.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/isa-bridge.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 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",
+ __func__);
+ return;
+ }
+
+ /* Align size and make sure it's cropped to 64K */
+ size = PAGE_ALIGN(range->size);
+ if (size > 0x10000)
+ size = 0x10000;
+
+ __ioremap_at(phb_io_base_phys, (void *)ISA_IO_BASE,
+ size, pgprot_val(pgprot_noncached(__pgprot(0))));
+ 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, pgprot_val(pgprot_noncached(__pgprot(0))));
+}
+
+
+/**
+ * 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->dn) {
+ 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 %pOF\n", np);
+}
+
+/**
+ * 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_init_non_pci(struct device_node *np)
+{
+ const __be32 *ranges, *pbasep = NULL;
+ int rlen, i, rs;
+ u32 na, ns, pna;
+ u64 cbase, pbase, size = 0;
+
+ /* If we already have an ISA bridge, bail off */
+ if (isa_bridge_devnode != NULL)
+ return;
+
+ pna = of_n_addr_cells(np);
+ if (of_property_read_u32(np, "#address-cells", &na) ||
+ of_property_read_u32(np, "#size-cells", &ns)) {
+ pr_warn("ISA: Non-PCI bridge %pOF is missing address format\n",
+ np);
+ return;
+ }
+
+ /* Check it's a supported address format */
+ if (na != 2 || ns != 1) {
+ pr_warn("ISA: Non-PCI bridge %pOF has unsupported address format\n",
+ np);
+ return;
+ }
+ rs = na + ns + pna;
+
+ /* Grab the ranges property */
+ ranges = of_get_property(np, "ranges", &rlen);
+ if (ranges == NULL || rlen < rs) {
+ pr_warn("ISA: Non-PCI bridge %pOF has absent or invalid ranges\n",
+ np);
+ return;
+ }
+
+ /* Parse it. We are only looking for IO space */
+ for (i = 0; (i + rs - 1) < rlen; i += rs) {
+ if (be32_to_cpup(ranges + i) != 1)
+ continue;
+ cbase = be32_to_cpup(ranges + i + 1);
+ size = of_read_number(ranges + i + na + pna, ns);
+ pbasep = ranges + i + na;
+ break;
+ }
+
+ /* Got something ? */
+ if (!size || !pbasep) {
+ pr_warn("ISA: Non-PCI bridge %pOF has no usable IO range\n",
+ np);
+ return;
+ }
+
+ /* Align size and make sure it's cropped to 64K */
+ size = PAGE_ALIGN(size);
+ if (size > 0x10000)
+ size = 0x10000;
+
+ /* Map pbase */
+ pbase = of_translate_address(np, pbasep);
+ if (pbase == OF_BAD_ADDR) {
+ pr_warn("ISA: Non-PCI bridge %pOF failed to translate IO base\n",
+ np);
+ return;
+ }
+
+ /* We need page alignment */
+ if ((cbase & ~PAGE_MASK) || (pbase & ~PAGE_MASK)) {
+ pr_warn("ISA: Non-PCI bridge %pOF has non aligned IO range\n",
+ np);
+ return;
+ }
+
+ /* Got it */
+ isa_bridge_devnode = np;
+
+ /* Set the global ISA io base to indicate we have an ISA bridge
+ * and map it
+ */
+ isa_io_base = ISA_IO_BASE;
+ __ioremap_at(pbase, (void *)ISA_IO_BASE,
+ size, pgprot_val(pgprot_noncached(__pgprot(0))));
+
+ pr_debug("ISA: Non-PCI bridge is %pOF\n", np);
+}
+
+/**
+ * isa_bridge_find_late - Find and map the ISA IO space upon discovery of
+ * a new ISA bridge
+ */
+static void 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 %pOF on %s\n",
+ devnode, 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 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)
+{
+ bus_register_notifier(&pci_bus_type, &isa_bridge_notifier);
+ return 0;
+}
+arch_initcall(isa_bridge_init);
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