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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/kernel/isa-bridge.c | |
parent | Initial commit. (diff) | |
download | linux-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.c | 276 |
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); |