summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/isa-bridge.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/kernel/isa-bridge.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/kernel/isa-bridge.c')
-rw-r--r--arch/powerpc/kernel/isa-bridge.c276
1 files changed, 276 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/isa-bridge.c b/arch/powerpc/kernel/isa-bridge.c
new file mode 100644
index 0000000000..48e0eaf1ad
--- /dev/null
+++ b/arch/powerpc/kernel/isa-bridge.c
@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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.
+ */
+
+#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 <linux/of_address.h>
+#include <linux/vmalloc.h>
+
+#include <asm/processor.h>
+#include <asm/io.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 remap_isa_base(phys_addr_t pa, unsigned long size)
+{
+ WARN_ON_ONCE(ISA_IO_BASE & ~PAGE_MASK);
+ WARN_ON_ONCE(pa & ~PAGE_MASK);
+ WARN_ON_ONCE(size & ~PAGE_MASK);
+
+ if (slab_is_available()) {
+ if (ioremap_page_range(ISA_IO_BASE, ISA_IO_BASE + size, pa,
+ pgprot_noncached(PAGE_KERNEL)))
+ vunmap_range(ISA_IO_BASE, ISA_IO_BASE + size);
+ } else {
+ early_ioremap_range(ISA_IO_BASE, pa, size,
+ pgprot_noncached(PAGE_KERNEL));
+ }
+}
+
+static int process_ISA_OF_ranges(struct device_node *isa_node,
+ unsigned long phb_io_base_phys)
+{
+ unsigned int size;
+ struct of_range_parser parser;
+ struct of_range range;
+
+ if (of_range_parser_init(&parser, isa_node))
+ goto inval_range;
+
+ for_each_of_range(&parser, &range) {
+ if ((range.flags & ISA_SPACE_MASK) != ISA_SPACE_IO)
+ continue;
+
+ if (range.cpu_addr == OF_BAD_ADDR) {
+ pr_err("ISA: Bad CPU mapping: %s\n", __func__);
+ return -EINVAL;
+ }
+
+ /* We need page alignment */
+ if ((range.bus_addr & ~PAGE_MASK) || (range.cpu_addr & ~PAGE_MASK)) {
+ pr_warn("ISA: bridge %pOF has non aligned IO range\n", isa_node);
+ return -EINVAL;
+ }
+
+ /* Align size and make sure it's cropped to 64K */
+ size = PAGE_ALIGN(range.size);
+ if (size > 0x10000)
+ size = 0x10000;
+
+ if (!phb_io_base_phys)
+ phb_io_base_phys = range.cpu_addr;
+
+ remap_isa_base(phb_io_base_phys, size);
+ return 0;
+ }
+
+inval_range:
+ if (phb_io_base_phys) {
+ pr_err("no ISA IO ranges or unexpected isa range, mapping 64k\n");
+ remap_isa_base(phb_io_base_phys, 0x10000);
+ return 0;
+ }
+ return -EINVAL;
+}
+
+
+/**
+ * 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 */
+ 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)
+{
+ int ret;
+
+ /* If we already have an ISA bridge, bail off */
+ if (isa_bridge_devnode != NULL)
+ return;
+
+ ret = process_ISA_OF_ranges(np, 0);
+ if (ret)
+ 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;
+
+ 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 */
+ 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 */
+ vunmap_range(ISA_IO_BASE, 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 && of_node_is_type(devnode, "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);