swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: f74c2bb98776e2de508f4d607cd519873065118e authored by Linus Torvalds on 08 September 2019, 20:33:15 UTC
Linux 5.3-rc8
Linux 5.3-rc8
Tip revision: f74c2bb
irq.c
// SPDX-License-Identifier: GPL-2.0+
/*
* Derived from arch/i386/kernel/irq.c
* Copyright (C) 1992 Linus Torvalds
* Adapted from arch/i386 by Gary Thomas
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
* Updated and modified by Cort Dougan <cort@fsmlabs.com>
* Copyright (C) 1996-2001 Cort Dougan
* Adapted for Power Macintosh by Paul Mackerras
* Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
*
* This file contains the code used to make IRQ descriptions in the
* device tree to actual irq numbers on an interrupt controller
* driver.
*/
#define pr_fmt(fmt) "OF: " fmt
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/string.h>
#include <linux/slab.h>
/**
* irq_of_parse_and_map - Parse and map an interrupt into linux virq space
* @dev: Device node of the device whose interrupt is to be mapped
* @index: Index of the interrupt to map
*
* This function is a wrapper that chains of_irq_parse_one() and
* irq_create_of_mapping() to make things easier to callers
*/
unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
{
struct of_phandle_args oirq;
if (of_irq_parse_one(dev, index, &oirq))
return 0;
return irq_create_of_mapping(&oirq);
}
EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
/**
* of_irq_find_parent - Given a device node, find its interrupt parent node
* @child: pointer to device node
*
* Returns a pointer to the interrupt parent node, or NULL if the interrupt
* parent could not be determined.
*/
struct device_node *of_irq_find_parent(struct device_node *child)
{
struct device_node *p;
phandle parent;
if (!of_node_get(child))
return NULL;
do {
if (of_property_read_u32(child, "interrupt-parent", &parent)) {
p = of_get_parent(child);
} else {
if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
p = of_node_get(of_irq_dflt_pic);
else
p = of_find_node_by_phandle(parent);
}
of_node_put(child);
child = p;
} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
return p;
}
EXPORT_SYMBOL_GPL(of_irq_find_parent);
/**
* of_irq_parse_raw - Low level interrupt tree parsing
* @addr: address specifier (start of "reg" property of the device) in be32 format
* @out_irq: structure of_phandle_args updated by this function
*
* Returns 0 on success and a negative number on error
*
* This function is a low-level interrupt tree walking function. It
* can be used to do a partial walk with synthetized reg and interrupts
* properties, for example when resolving PCI interrupts when no device
* node exist for the parent. It takes an interrupt specifier structure as
* input, walks the tree looking for any interrupt-map properties, translates
* the specifier for each map, and then returns the translated map.
*/
int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
{
struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
__be32 initial_match_array[MAX_PHANDLE_ARGS];
const __be32 *match_array = initial_match_array;
const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) };
u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
int imaplen, match, i, rc = -EINVAL;
#ifdef DEBUG
of_print_phandle_args("of_irq_parse_raw: ", out_irq);
#endif
ipar = of_node_get(out_irq->np);
/* First get the #interrupt-cells property of the current cursor
* that tells us how to interpret the passed-in intspec. If there
* is none, we are nice and just walk up the tree
*/
do {
if (!of_property_read_u32(ipar, "#interrupt-cells", &intsize))
break;
tnode = ipar;
ipar = of_irq_find_parent(ipar);
of_node_put(tnode);
} while (ipar);
if (ipar == NULL) {
pr_debug(" -> no parent found !\n");
goto fail;
}
pr_debug("of_irq_parse_raw: ipar=%pOF, size=%d\n", ipar, intsize);
if (out_irq->args_count != intsize)
goto fail;
/* Look for this #address-cells. We have to implement the old linux
* trick of looking for the parent here as some device-trees rely on it
*/
old = of_node_get(ipar);
do {
tmp = of_get_property(old, "#address-cells", NULL);
tnode = of_get_parent(old);
of_node_put(old);
old = tnode;
} while (old && tmp == NULL);
of_node_put(old);
old = NULL;
addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
pr_debug(" -> addrsize=%d\n", addrsize);
/* Range check so that the temporary buffer doesn't overflow */
if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) {
rc = -EFAULT;
goto fail;
}
/* Precalculate the match array - this simplifies match loop */
for (i = 0; i < addrsize; i++)
initial_match_array[i] = addr ? addr[i] : 0;
for (i = 0; i < intsize; i++)
initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);
/* Now start the actual "proper" walk of the interrupt tree */
while (ipar != NULL) {
/* Now check if cursor is an interrupt-controller and if it is
* then we are done
*/
if (of_property_read_bool(ipar, "interrupt-controller")) {
pr_debug(" -> got it !\n");
return 0;
}
/*
* interrupt-map parsing does not work without a reg
* property when #address-cells != 0
*/
if (addrsize && !addr) {
pr_debug(" -> no reg passed in when needed !\n");
goto fail;
}
/* Now look for an interrupt-map */
imap = of_get_property(ipar, "interrupt-map", &imaplen);
/* No interrupt map, check for an interrupt parent */
if (imap == NULL) {
pr_debug(" -> no map, getting parent\n");
newpar = of_irq_find_parent(ipar);
goto skiplevel;
}
imaplen /= sizeof(u32);
/* Look for a mask */
imask = of_get_property(ipar, "interrupt-map-mask", NULL);
if (!imask)
imask = dummy_imask;
/* Parse interrupt-map */
match = 0;
while (imaplen > (addrsize + intsize + 1) && !match) {
/* Compare specifiers */
match = 1;
for (i = 0; i < (addrsize + intsize); i++, imaplen--)
match &= !((match_array[i] ^ *imap++) & imask[i]);
pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
/* Get the interrupt parent */
if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
newpar = of_node_get(of_irq_dflt_pic);
else
newpar = of_find_node_by_phandle(be32_to_cpup(imap));
imap++;
--imaplen;
/* Check if not found */
if (newpar == NULL) {
pr_debug(" -> imap parent not found !\n");
goto fail;
}
if (!of_device_is_available(newpar))
match = 0;
/* Get #interrupt-cells and #address-cells of new
* parent
*/
if (of_property_read_u32(newpar, "#interrupt-cells",
&newintsize)) {
pr_debug(" -> parent lacks #interrupt-cells!\n");
goto fail;
}
if (of_property_read_u32(newpar, "#address-cells",
&newaddrsize))
newaddrsize = 0;
pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
newintsize, newaddrsize);
/* Check for malformed properties */
if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS)
|| (imaplen < (newaddrsize + newintsize))) {
rc = -EFAULT;
goto fail;
}
imap += newaddrsize + newintsize;
imaplen -= newaddrsize + newintsize;
pr_debug(" -> imaplen=%d\n", imaplen);
}
if (!match)
goto fail;
/*
* Successfully parsed an interrrupt-map translation; copy new
* interrupt specifier into the out_irq structure
*/
match_array = imap - newaddrsize - newintsize;
for (i = 0; i < newintsize; i++)
out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
out_irq->args_count = intsize = newintsize;
addrsize = newaddrsize;
skiplevel:
/* Iterate again with new parent */
out_irq->np = newpar;
pr_debug(" -> new parent: %pOF\n", newpar);
of_node_put(ipar);
ipar = newpar;
newpar = NULL;
}
rc = -ENOENT; /* No interrupt-map found */
fail:
of_node_put(ipar);
of_node_put(newpar);
return rc;
}
EXPORT_SYMBOL_GPL(of_irq_parse_raw);
/**
* of_irq_parse_one - Resolve an interrupt for a device
* @device: the device whose interrupt is to be resolved
* @index: index of the interrupt to resolve
* @out_irq: structure of_phandle_args filled by this function
*
* This function resolves an interrupt for a node by walking the interrupt tree,
* finding which interrupt controller node it is attached to, and returning the
* interrupt specifier that can be used to retrieve a Linux IRQ number.
*/
int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
{
struct device_node *p;
const __be32 *addr;
u32 intsize;
int i, res;
pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
/* OldWorld mac stuff is "special", handle out of line */
if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
return of_irq_parse_oldworld(device, index, out_irq);
/* Get the reg property (if any) */
addr = of_get_property(device, "reg", NULL);
/* Try the new-style interrupts-extended first */
res = of_parse_phandle_with_args(device, "interrupts-extended",
"#interrupt-cells", index, out_irq);
if (!res)
return of_irq_parse_raw(addr, out_irq);
/* Look for the interrupt parent. */
p = of_irq_find_parent(device);
if (p == NULL)
return -EINVAL;
/* Get size of interrupt specifier */
if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
res = -EINVAL;
goto out;
}
pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
/* Copy intspec into irq structure */
out_irq->np = p;
out_irq->args_count = intsize;
for (i = 0; i < intsize; i++) {
res = of_property_read_u32_index(device, "interrupts",
(index * intsize) + i,
out_irq->args + i);
if (res)
goto out;
}
pr_debug(" intspec=%d\n", *out_irq->args);
/* Check if there are any interrupt-map translations to process */
res = of_irq_parse_raw(addr, out_irq);
out:
of_node_put(p);
return res;
}
EXPORT_SYMBOL_GPL(of_irq_parse_one);
/**
* of_irq_to_resource - Decode a node's IRQ and return it as a resource
* @dev: pointer to device tree node
* @index: zero-based index of the irq
* @r: pointer to resource structure to return result into.
*/
int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
{
int irq = of_irq_get(dev, index);
if (irq < 0)
return irq;
/* Only dereference the resource if both the
* resource and the irq are valid. */
if (r && irq) {
const char *name = NULL;
memset(r, 0, sizeof(*r));
/*
* Get optional "interrupt-names" property to add a name
* to the resource.
*/
of_property_read_string_index(dev, "interrupt-names", index,
&name);
r->start = r->end = irq;
r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq));
r->name = name ? name : of_node_full_name(dev);
}
return irq;
}
EXPORT_SYMBOL_GPL(of_irq_to_resource);
/**
* of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
* @dev: pointer to device tree node
* @index: zero-based index of the IRQ
*
* Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
* -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
* of any other failure.
*/
int of_irq_get(struct device_node *dev, int index)
{
int rc;
struct of_phandle_args oirq;
struct irq_domain *domain;
rc = of_irq_parse_one(dev, index, &oirq);
if (rc)
return rc;
domain = irq_find_host(oirq.np);
if (!domain)
return -EPROBE_DEFER;
return irq_create_of_mapping(&oirq);
}
EXPORT_SYMBOL_GPL(of_irq_get);
/**
* of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
* @dev: pointer to device tree node
* @name: IRQ name
*
* Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
* -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
* of any other failure.
*/
int of_irq_get_byname(struct device_node *dev, const char *name)
{
int index;
if (unlikely(!name))
return -EINVAL;
index = of_property_match_string(dev, "interrupt-names", name);
if (index < 0)
return index;
return of_irq_get(dev, index);
}
EXPORT_SYMBOL_GPL(of_irq_get_byname);
/**
* of_irq_count - Count the number of IRQs a node uses
* @dev: pointer to device tree node
*/
int of_irq_count(struct device_node *dev)
{
struct of_phandle_args irq;
int nr = 0;
while (of_irq_parse_one(dev, nr, &irq) == 0)
nr++;
return nr;
}
/**
* of_irq_to_resource_table - Fill in resource table with node's IRQ info
* @dev: pointer to device tree node
* @res: array of resources to fill in
* @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
*
* Returns the size of the filled in table (up to @nr_irqs).
*/
int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
int nr_irqs)
{
int i;
for (i = 0; i < nr_irqs; i++, res++)
if (of_irq_to_resource(dev, i, res) <= 0)
break;
return i;
}
EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
struct of_intc_desc {
struct list_head list;
of_irq_init_cb_t irq_init_cb;
struct device_node *dev;
struct device_node *interrupt_parent;
};
/**
* of_irq_init - Scan and init matching interrupt controllers in DT
* @matches: 0 terminated array of nodes to match and init function to call
*
* This function scans the device tree for matching interrupt controller nodes,
* and calls their initialization functions in order with parents first.
*/
void __init of_irq_init(const struct of_device_id *matches)
{
const struct of_device_id *match;
struct device_node *np, *parent = NULL;
struct of_intc_desc *desc, *temp_desc;
struct list_head intc_desc_list, intc_parent_list;
INIT_LIST_HEAD(&intc_desc_list);
INIT_LIST_HEAD(&intc_parent_list);
for_each_matching_node_and_match(np, matches, &match) {
if (!of_property_read_bool(np, "interrupt-controller") ||
!of_device_is_available(np))
continue;
if (WARN(!match->data, "of_irq_init: no init function for %s\n",
match->compatible))
continue;
/*
* Here, we allocate and populate an of_intc_desc with the node
* pointer, interrupt-parent device_node etc.
*/
desc = kzalloc(sizeof(*desc), GFP_KERNEL);
if (!desc) {
of_node_put(np);
goto err;
}
desc->irq_init_cb = match->data;
desc->dev = of_node_get(np);
desc->interrupt_parent = of_irq_find_parent(np);
if (desc->interrupt_parent == np)
desc->interrupt_parent = NULL;
list_add_tail(&desc->list, &intc_desc_list);
}
/*
* The root irq controller is the one without an interrupt-parent.
* That one goes first, followed by the controllers that reference it,
* followed by the ones that reference the 2nd level controllers, etc.
*/
while (!list_empty(&intc_desc_list)) {
/*
* Process all controllers with the current 'parent'.
* First pass will be looking for NULL as the parent.
* The assumption is that NULL parent means a root controller.
*/
list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
int ret;
if (desc->interrupt_parent != parent)
continue;
list_del(&desc->list);
of_node_set_flag(desc->dev, OF_POPULATED);
pr_debug("of_irq_init: init %pOF (%p), parent %p\n",
desc->dev,
desc->dev, desc->interrupt_parent);
ret = desc->irq_init_cb(desc->dev,
desc->interrupt_parent);
if (ret) {
of_node_clear_flag(desc->dev, OF_POPULATED);
kfree(desc);
continue;
}
/*
* This one is now set up; add it to the parent list so
* its children can get processed in a subsequent pass.
*/
list_add_tail(&desc->list, &intc_parent_list);
}
/* Get the next pending parent that might have children */
desc = list_first_entry_or_null(&intc_parent_list,
typeof(*desc), list);
if (!desc) {
pr_err("of_irq_init: children remain, but no parents\n");
break;
}
list_del(&desc->list);
parent = desc->dev;
kfree(desc);
}
list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
list_del(&desc->list);
kfree(desc);
}
err:
list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
list_del(&desc->list);
of_node_put(desc->dev);
kfree(desc);
}
}
static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
u32 rid_in)
{
struct device *parent_dev;
u32 rid_out = rid_in;
/*
* Walk up the device parent links looking for one with a
* "msi-map" property.
*/
for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
if (!of_map_rid(parent_dev->of_node, rid_in, "msi-map",
"msi-map-mask", np, &rid_out))
break;
return rid_out;
}
/**
* of_msi_map_rid - Map a MSI requester ID for a device.
* @dev: device for which the mapping is to be done.
* @msi_np: device node of the expected msi controller.
* @rid_in: unmapped MSI requester ID for the device.
*
* Walk up the device hierarchy looking for devices with a "msi-map"
* property. If found, apply the mapping to @rid_in.
*
* Returns the mapped MSI requester ID.
*/
u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
{
return __of_msi_map_rid(dev, &msi_np, rid_in);
}
/**
* of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
* @dev: device for which the mapping is to be done.
* @rid: Requester ID for the device.
*
* Walk up the device hierarchy looking for devices with a "msi-map"
* property.
*
* Returns: the MSI domain for this device (or NULL on failure)
*/
struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid)
{
struct device_node *np = NULL;
__of_msi_map_rid(dev, &np, rid);
return irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI);
}
/**
* of_msi_get_domain - Use msi-parent to find the relevant MSI domain
* @dev: device for which the domain is requested
* @np: device node for @dev
* @token: bus type for this domain
*
* Parse the msi-parent property (both the simple and the complex
* versions), and returns the corresponding MSI domain.
*
* Returns: the MSI domain for this device (or NULL on failure).
*/
struct irq_domain *of_msi_get_domain(struct device *dev,
struct device_node *np,
enum irq_domain_bus_token token)
{
struct device_node *msi_np;
struct irq_domain *d;
/* Check for a single msi-parent property */
msi_np = of_parse_phandle(np, "msi-parent", 0);
if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
d = irq_find_matching_host(msi_np, token);
if (!d)
of_node_put(msi_np);
return d;
}
if (token == DOMAIN_BUS_PLATFORM_MSI) {
/* Check for the complex msi-parent version */
struct of_phandle_args args;
int index = 0;
while (!of_parse_phandle_with_args(np, "msi-parent",
"#msi-cells",
index, &args)) {
d = irq_find_matching_host(args.np, token);
if (d)
return d;
of_node_put(args.np);
index++;
}
}
return NULL;
}
/**
* of_msi_configure - Set the msi_domain field of a device
* @dev: device structure to associate with an MSI irq domain
* @np: device node for that device
*/
void of_msi_configure(struct device *dev, struct device_node *np)
{
dev_set_msi_domain(dev,
of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI));
}
EXPORT_SYMBOL_GPL(of_msi_configure);