| /* | 
 |  * 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); |