[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / powerpc / kernel / isa-bridge.c

/*
 * 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>

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, _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->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 %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 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 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);
Commit	Line	Data
3d5134ee BH	1	/*
	2	* Routines for tracking a legacy ISA bridge
	3	*
	4	* Copyrigh 2007 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
	5	*
	6	* Some bits and pieces moved over from pci_64.c
	7	*
	8	* Copyrigh 2003 Anton Blanchard <anton@au.ibm.com>, IBM Corp.
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License
	12	* as published by the Free Software Foundation; either version
	13	* 2 of the License, or (at your option) any later version.
	14	*/
	15
	16	#define DEBUG
	17
	18	#include <linux/kernel.h>
	19	#include <linux/pci.h>
	20	#include <linux/string.h>
66b15db6	21	#include <linux/export.h>
3d5134ee BH	22	#include <linux/init.h>
	23	#include <linux/mm.h>
	24	#include <linux/notifier.h>
	25
	26	#include <asm/processor.h>
	27	#include <asm/io.h>
	28	#include <asm/prom.h>
	29	#include <asm/pci-bridge.h>
	30	#include <asm/machdep.h>
	31	#include <asm/ppc-pci.h>
3d5134ee BH	32
	33	unsigned long isa_io_base; /* NULL if no ISA bus */
	34	EXPORT_SYMBOL(isa_io_base);
	35
	36	/* Cached ISA bridge dev. */
	37	static struct device_node *isa_bridge_devnode;
	38	struct pci_dev *isa_bridge_pcidev;
	39	EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
	40
	41	#define ISA_SPACE_MASK 0x1
	42	#define ISA_SPACE_IO 0x1
	43
cad5cef6 GKH	44	static void pci_process_ISA_OF_ranges(struct device_node *isa_node,
cad5cef6 GKH	45	unsigned long phb_io_base_phys)
3d5134ee BH	46	{
	47	/* We should get some saner parsing here and remove these structs */
	48	struct pci_address {
	49	u32 a_hi;
	50	u32 a_mid;
	51	u32 a_lo;
	52	};
	53
	54	struct isa_address {
	55	u32 a_hi;
	56	u32 a_lo;
	57	};
	58
	59	struct isa_range {
	60	struct isa_address isa_addr;
	61	struct pci_address pci_addr;
	62	unsigned int size;
	63	};
	64
	65	const struct isa_range *range;
	66	unsigned long pci_addr;
	67	unsigned int isa_addr;
	68	unsigned int size;
	69	int rlen = 0;
	70
	71	range = of_get_property(isa_node, "ranges", &rlen);
	72	if (range == NULL \|\| (rlen < sizeof(struct isa_range)))
	73	goto inval_range;
	74
	75	/* From "ISA Binding to 1275"
	76	* The ranges property is laid out as an array of elements,
	77	* each of which comprises:
	78	* cells 0 - 1: an ISA address
	79	* cells 2 - 4: a PCI address
	80	* (size depending on dev->n_addr_cells)
	81	* cell 5: the size of the range
	82	*/
4df4441e	83	if ((range->isa_addr.a_hi & ISA_SPACE_MASK) != ISA_SPACE_IO) {
3d5134ee BH	84	range++;
	85	rlen -= sizeof(struct isa_range);
	86	if (rlen < sizeof(struct isa_range))
	87	goto inval_range;
	88	}
4df4441e	89	if ((range->isa_addr.a_hi & ISA_SPACE_MASK) != ISA_SPACE_IO)
3d5134ee BH	90	goto inval_range;
	91
	92	isa_addr = range->isa_addr.a_lo;
	93	pci_addr = (unsigned long) range->pci_addr.a_mid << 32 \|
	94	range->pci_addr.a_lo;
	95
	96	/* Assume these are both zero. Note: We could fix that and
	97	* do a proper parsing instead ... oh well, that will do for
	98	* now as nobody uses fancy mappings for ISA bridges
	99	*/
	100	if ((pci_addr != 0) \|\| (isa_addr != 0)) {
	101	printk(KERN_ERR "unexpected isa to pci mapping: %s\n",
e48b1b45	102	__func__);
3d5134ee BH	103	return;
	104	}
	105
	106	/* Align size and make sure it's cropped to 64K */
	107	size = PAGE_ALIGN(range->size);
	108	if (size > 0x10000)
	109	size = 0x10000;
	110
3d5134ee BH	111	__ioremap_at(phb_io_base_phys, (void *)ISA_IO_BASE,
	112	size, _PAGE_NO_CACHE\|_PAGE_GUARDED);
	113	return;
	114
	115	inval_range:
df3c9019	116	printk(KERN_ERR "no ISA IO ranges or unexpected isa range, "
3d5134ee BH	117	"mapping 64k\n");
	118	__ioremap_at(phb_io_base_phys, (void *)ISA_IO_BASE,
	119	0x10000, _PAGE_NO_CACHE\|_PAGE_GUARDED);
	120	}
	121
	122
	123	/**
	124	* isa_bridge_find_early - Find and map the ISA IO space early before
	125	* main PCI discovery. This is optionally called by
	126	* the arch code when adding PCI PHBs to get early
	127	* access to ISA IO ports
	128	*/
	129	void __init isa_bridge_find_early(struct pci_controller *hose)
	130	{
	131	struct device_node np, parent = NULL, *tmp;
	132
	133	/* If we already have an ISA bridge, bail off */
	134	if (isa_bridge_devnode != NULL)
	135	return;
	136
	137	/* For each "isa" node in the system. Note : we do a search by
	138	* type and not by name. It might be better to do by name but that's
	139	* what the code used to do and I don't want to break too much at
	140	* once. We can look into changing that separately
	141	*/
	142	for_each_node_by_type(np, "isa") {
	143	/* Look for our hose being a parent */
	144	for (parent = of_get_parent(np); parent;) {
44ef3390	145	if (parent == hose->dn) {
3d5134ee BH	146	of_node_put(parent);
	147	break;
	148	}
	149	tmp = parent;
	150	parent = of_get_parent(parent);
	151	of_node_put(tmp);
	152	}
	153	if (parent != NULL)
	154	break;
	155	}
	156	if (np == NULL)
	157	return;
	158	isa_bridge_devnode = np;
	159
	160	/* Now parse the "ranges" property and setup the ISA mapping */
	161	pci_process_ISA_OF_ranges(np, hose->io_base_phys);
	162
	163	/* Set the global ISA io base to indicate we have an ISA bridge */
	164	isa_io_base = ISA_IO_BASE;
	165
	166	pr_debug("ISA bridge (early) is %s\n", np->full_name);
	167	}
	168
	169	/**
	170	* isa_bridge_find_late - Find and map the ISA IO space upon discovery of
	171	* a new ISA bridge
	172	*/
cad5cef6 GKH	173	static void isa_bridge_find_late(struct pci_dev *pdev,
cad5cef6 GKH	174	struct device_node *devnode)
3d5134ee BH	175	{
	176	struct pci_controller *hose = pci_bus_to_host(pdev->bus);
	177
	178	/* Store ISA device node and PCI device */
	179	isa_bridge_devnode = of_node_get(devnode);
	180	isa_bridge_pcidev = pdev;
	181
	182	/* Now parse the "ranges" property and setup the ISA mapping */
	183	pci_process_ISA_OF_ranges(devnode, hose->io_base_phys);
	184
	185	/* Set the global ISA io base to indicate we have an ISA bridge */
	186	isa_io_base = ISA_IO_BASE;
	187
	188	pr_debug("ISA bridge (late) is %s on %s\n",
	189	devnode->full_name, pci_name(pdev));
	190	}
	191
	192	/**
	193	* isa_bridge_remove - Remove/unmap an ISA bridge
	194	*/
	195	static void isa_bridge_remove(void)
	196	{
	197	pr_debug("ISA bridge removed !\n");
	198
	199	/* Clear the global ISA io base to indicate that we have no more
	200	* ISA bridge. Note that drivers don't quite handle that, though
	201	* we should probably do something about it. But do we ever really
	202	* have ISA bridges being removed on machines using legacy devices ?
	203	*/
	204	isa_io_base = ISA_IO_BASE;
	205
	206	/* Clear references to the bridge */
	207	of_node_put(isa_bridge_devnode);
	208	isa_bridge_devnode = NULL;
	209	isa_bridge_pcidev = NULL;
	210
	211	/* Unmap the ISA area */
	212	__iounmap_at((void *)ISA_IO_BASE, 0x10000);
	213	}
	214
	215	/**
	216	* isa_bridge_notify - Get notified of PCI devices addition/removal
	217	*/
cad5cef6 GKH	218	static int isa_bridge_notify(struct notifier_block *nb, unsigned long action,
cad5cef6 GKH	219	void *data)
3d5134ee BH	220	{
	221	struct device *dev = data;
	222	struct pci_dev *pdev = to_pci_dev(dev);
	223	struct device_node *devnode = pci_device_to_OF_node(pdev);
	224
	225	switch(action) {
	226	case BUS_NOTIFY_ADD_DEVICE:
	227	/* Check if we have an early ISA device, without PCI dev */
	228	if (isa_bridge_devnode && isa_bridge_devnode == devnode &&
	229	!isa_bridge_pcidev) {
	230	pr_debug("ISA bridge PCI attached: %s\n",
	231	pci_name(pdev));
	232	isa_bridge_pcidev = pdev;
	233	}
	234
	235	/* Check if we have no ISA device, and this happens to be one,
	236	* register it as such if it has an OF device
	237	*/
	238	if (!isa_bridge_devnode && devnode && devnode->type &&
	239	!strcmp(devnode->type, "isa"))
	240	isa_bridge_find_late(pdev, devnode);
	241
	242	return 0;
	243	case BUS_NOTIFY_DEL_DEVICE:
	244	/* Check if this our existing ISA device */
	245	if (pdev == isa_bridge_pcidev \|\|
	246	(devnode && devnode == isa_bridge_devnode))
	247	isa_bridge_remove();
	248	return 0;
	249	}
	250	return 0;
	251	}
	252
	253	static struct notifier_block isa_bridge_notifier = {
	254	.notifier_call = isa_bridge_notify
	255	};
	256
	257	/**
	258	* isa_bridge_init - register to be notified of ISA bridge addition/removal
	259	*
	260	*/
	261	static int __init isa_bridge_init(void)
	262	{
3d5134ee BH	263	bus_register_notifier(&pci_bus_type, &isa_bridge_notifier);
	264	return 0;
	265	}
	266	arch_initcall(isa_bridge_init);