- 根目录:
- drivers
- of
- address.c
#include <linux/device.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/pci_regs.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/string.h>
/* Max address size we deal with */
#define OF_MAX_ADDR_CELLS 4
#define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
#define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
static struct of_bus *of_match_bus(struct device_node *np);
static int __of_address_to_resource(struct device_node *dev,
const __be32 *addrp, u64 size, unsigned int flags,
const char *name, struct resource *r);
/* Debug utility */
#ifdef DEBUG
static void of_dump_addr(const char *s, const __be32 *addr, int na)
{
printk(KERN_DEBUG "%s", s);
while (na--)
printk(" %08x", be32_to_cpu(*(addr++)));
printk("\n");
}
#else
static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
#endif
/* Callbacks for bus specific translators */
struct of_bus {
const char *name;
const char *addresses;
int (*match)(struct device_node *parent);
void (*count_cells)(struct device_node *child,
int *addrc, int *sizec);
u64 (*map)(__be32 *addr, const __be32 *range,
int na, int ns, int pna);
int (*translate)(__be32 *addr, u64 offset, int na);
unsigned int (*get_flags)(const __be32 *addr);
};
/*
* Default translator (generic bus)
*/
static void of_bus_default_count_cells(struct device_node *dev,
int *addrc, int *sizec)
{
if (addrc)
*addrc = of_n_addr_cells(dev);
if (sizec)
*sizec = of_n_size_cells(dev);
}
static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
int na, int ns, int pna)
{
u64 cp, s, da;
cp = of_read_number(range, na);
s = of_read_number(range + na + pna, ns);
da = of_read_number(addr, na);
pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
(unsigned long long)cp, (unsigned long long)s,
(unsigned long long)da);
if (da < cp || da >= (cp + s))
return OF_BAD_ADDR;
return da - cp;
}
static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
{
u64 a = of_read_number(addr, na);
memset(addr, 0, na * 4);
a += offset;
if (na > 1)
addr[na - 2] = cpu_to_be32(a >> 32);
addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
return 0;
}
static unsigned int of_bus_default_get_flags(const __be32 *addr)
{
return IORESOURCE_MEM;
}
#ifdef CONFIG_OF_ADDRESS_PCI
/*
* PCI bus specific translator
*/
static int of_bus_pci_match(struct device_node *np)
{
/*
* "pciex" is PCI Express
* "vci" is for the /chaos bridge on 1st-gen PCI powermacs
* "ht" is hypertransport
*/
return !strcmp(np->type, "pci") || !strcmp(np->type, "pciex") ||
!strcmp(np->type, "vci") || !strcmp(np->type, "ht");
}
static void of_bus_pci_count_cells(struct device_node *np,
int *addrc, int *sizec)
{
if (addrc)
*addrc = 3;
if (sizec)
*sizec = 2;
}
static unsigned int of_bus_pci_get_flags(const __be32 *addr)
{
unsigned int flags = 0;
u32 w = be32_to_cpup(addr);
switch((w >> 24) & 0x03) {
case 0x01:
flags |= IORESOURCE_IO;
break;
case 0x02: /* 32 bits */
case 0x03: /* 64 bits */
flags |= IORESOURCE_MEM;
break;
}
if (w & 0x40000000)
flags |= IORESOURCE_PREFETCH;
return flags;
}
static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
int pna)
{
u64 cp, s, da;
unsigned int af, rf;
af = of_bus_pci_get_flags(addr);
rf = of_bus_pci_get_flags(range);
/* Check address type match */
if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
return OF_BAD_ADDR;
/* Read address values, skipping high cell */
cp = of_read_number(range + 1, na - 1);
s = of_read_number(range + na + pna, ns);
da = of_read_number(addr + 1, na - 1);
pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
(unsigned long long)cp, (unsigned long long)s,
(unsigned long long)da);
if (da < cp || da >= (cp + s))
return OF_BAD_ADDR;
return da - cp;
}
static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
{
return of_bus_default_translate(addr + 1, offset, na - 1);
}
#endif /* CONFIG_OF_ADDRESS_PCI */
#ifdef CONFIG_PCI
const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
unsigned int *flags)
{
const __be32 *prop;
unsigned int psize;
struct device_node *parent;
struct of_bus *bus;
int onesize, i, na, ns;
/* Get parent & match bus type */
parent = of_get_parent(dev);
if (parent == NULL)
return NULL;
bus = of_match_bus(parent);
if (strcmp(bus->name, "pci")) {
of_node_put(parent);
return NULL;
}
bus->count_cells(dev, &na, &ns);
of_node_put(parent);
if (!OF_CHECK_ADDR_COUNT(na))
return NULL;
/* Get "reg" or "assigned-addresses" property */
prop = of_get_property(dev, bus->addresses, &psize);
if (prop == NULL)
return NULL;
psize /= 4;
onesize = na + ns;
for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
u32 val = be32_to_cpu(prop[0]);
if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
if (size)
*size = of_read_number(prop + na, ns);
if (flags)
*flags = bus->get_flags(prop);
return prop;
}
}
return NULL;
}
EXPORT_SYMBOL(of_get_pci_address);
int of_pci_address_to_resource(struct device_node *dev, int bar,
struct resource *r)
{
const __be32 *addrp;
u64 size;
unsigned int flags;
addrp = of_get_pci_address(dev, bar, &size, &flags);
if (addrp == NULL)
return -EINVAL;
return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
}
EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
int of_pci_range_parser_init(struct of_pci_range_parser *parser,
struct device_node *node)
{
const int na = 3, ns = 2;
int rlen;
parser->node = node;
parser->pna = of_n_addr_cells(node);
parser->np = parser->pna + na + ns;
parser->range = of_get_property(node, "ranges", &rlen);
if (parser->range == NULL)
return -ENOENT;
parser->end = parser->range + rlen / sizeof(__be32);
return 0;
}
EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
struct of_pci_range *range)
{
const int na = 3, ns = 2;
if (!range)
return NULL;
if (!parser->range || parser->range + parser->np > parser->end)
return NULL;
range->pci_space = parser->range[0];
range->flags = of_bus_pci_get_flags(parser->range);
range->pci_addr = of_read_number(parser->range + 1, ns);
range->cpu_addr = of_translate_address(parser->node,
parser->range + na);
range->size = of_read_number(parser->range + parser->pna + na, ns);
parser->range += parser->np;
/* Now consume following elements while they are contiguous */
while (parser->range + parser->np <= parser->end) {
u32 flags, pci_space;
u64 pci_addr, cpu_addr, size;
pci_space = be32_to_cpup(parser->range);
flags = of_bus_pci_get_flags(parser->range);
pci_addr = of_read_number(parser->range + 1, ns);
cpu_addr = of_translate_address(parser->node,
parser->range + na);
size = of_read_number(parser->range + parser->pna + na, ns);
if (flags != range->flags)
break;
if (pci_addr != range->pci_addr + range->size ||
cpu_addr != range->cpu_addr + range->size)
break;
range->size += size;
parser->range += parser->np;
}
return range;
}
EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
/*
* of_pci_range_to_resource - Create a resource from an of_pci_range
* @range: the PCI range that describes the resource
* @np: device node where the range belongs to
* @res: pointer to a valid resource that will be updated to
* reflect the values contained in the range.
*
* Returns EINVAL if the range cannot be converted to resource.
*
* Note that if the range is an IO range, the resource will be converted
* using pci_address_to_pio() which can fail if it is called too early or
* if the range cannot be matched to any host bridge IO space (our case here).
* To guard against that we try to register the IO range first.
* If that fails we know that pci_address_to_pio() will do too.
*/
int of_pci_range_to_resource(struct of_pci_range *range,
struct device_node *np, struct resource *res)
{
int err;
res->flags = range->flags;
res->parent = res->child = res->sibling = NULL;
res->name = np->full_name;
if (res->flags & IORESOURCE_IO) {
unsigned long port;
err = pci_register_io_range(range->cpu_addr, range->size);
if (err)
goto invalid_range;
port = pci_address_to_pio(range->cpu_addr);
if (port == (unsigned long)-1) {
err = -EINVAL;
goto invalid_range;
}
res->start = port;
} else {
if ((sizeof(resource_size_t) < 8) &&
upper_32_bits(range->cpu_addr)) {
err = -EINVAL;
goto invalid_range;
}
res->start = range->cpu_addr;
}
res->end = res->start + range->size - 1;
return 0;
invalid_range:
res->start = (resource_size_t)OF_BAD_ADDR;
res->end = (resource_size_t)OF_BAD_ADDR;
return err;
}
#endif /* CONFIG_PCI */
/*
* ISA bus specific translator
*/
static int of_bus_isa_match(struct device_node *np)
{
return !strcmp(np->name, "isa");
}
static void of_bus_isa_count_cells(struct device_node *child,
int *addrc, int *sizec)
{
if (addrc)
*addrc = 2;
if (sizec)
*sizec = 1;
}
static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
int pna)
{
u64 cp, s, da;
/* Check address type match */
if ((addr[0] ^ range[0]) & cpu_to_be32(1))
return OF_BAD_ADDR;
/* Read address values, skipping high cell */
cp = of_read_number(range + 1, na - 1);
s = of_read_number(range + na + pna, ns);
da = of_read_number(addr + 1, na - 1);
pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
(unsigned long long)cp, (unsigned long long)s,
(unsigned long long)da);
if (da < cp || da >= (cp + s))
return OF_BAD_ADDR;
return da - cp;
}
static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
{
return of_bus_default_translate(addr + 1, offset, na - 1);
}
static unsigned int of_bus_isa_get_flags(const __be32 *addr)
{
unsigned int flags = 0;
u32 w = be32_to_cpup(addr);
if (w & 1)
flags |= IORESOURCE_IO;
else
flags |= IORESOURCE_MEM;
return flags;
}
/*
* Array of bus specific translators
*/
static struct of_bus of_busses[] = {
#ifdef CONFIG_OF_ADDRESS_PCI
/* PCI */
{
.name = "pci",
.addresses = "assigned-addresses",
.match = of_bus_pci_match,
.count_cells = of_bus_pci_count_cells,
.map = of_bus_pci_map,
.translate = of_bus_pci_translate,
.get_flags = of_bus_pci_get_flags,
},
#endif /* CONFIG_OF_ADDRESS_PCI */
/* ISA */
{
.name = "isa",
.addresses = "reg",
.match = of_bus_isa_match,
.count_cells = of_bus_isa_count_cells,
.map = of_bus_isa_map,
.translate = of_bus_isa_translate,
.get_flags = of_bus_isa_get_flags,
},
/* Default */
{
.name = "default",
.addresses = "reg",
.match = NULL,
.count_cells = of_bus_default_count_cells,
.map = of_bus_default_map,
.translate = of_bus_default_translate,
.get_flags = of_bus_default_get_flags,
},
};
static struct of_bus *of_match_bus(struct device_node *np)
{
int i;
for (i = 0; i < ARRAY_SIZE(of_busses); i++)
if (!of_busses[i].match || of_busses[i].match(np))
return &of_busses[i];
BUG();
return NULL;
}
static int of_empty_ranges_quirk(struct device_node *np)
{
if (IS_ENABLED(CONFIG_PPC)) {
/* To save cycles, we cache the result for global "Mac" setting */
static int quirk_state = -1;
/* PA-SEMI sdc DT bug */
if (of_device_is_compatible(np, "1682m-sdc"))
return true;
/* Make quirk cached */
if (quirk_state < 0)
quirk_state =
of_machine_is_compatible("Power Macintosh") ||
of_machine_is_compatible("MacRISC");
return quirk_state;
}
return false;
}
static int of_translate_one(struct device_node *parent, struct of_bus *bus,
struct of_bus *pbus, __be32 *addr,
int na, int ns, int pna, const char *rprop)
{
const __be32 *ranges;
unsigned int rlen;
int rone;
u64 offset = OF_BAD_ADDR;
/*
* Normally, an absence of a "ranges" property means we are
* crossing a non-translatable boundary, and thus the addresses
* below the current cannot be converted to CPU physical ones.
* Unfortunately, while this is very clear in the spec, it's not
* what Apple understood, and they do have things like /uni-n or
* /ht nodes with no "ranges" property and a lot of perfectly
* useable mapped devices below them. Thus we treat the absence of
* "ranges" as equivalent to an empty "ranges" property which means
* a 1:1 translation at that level. It's up to the caller not to try
* to translate addresses that aren't supposed to be translated in
* the first place. --BenH.
*
* As far as we know, this damage only exists on Apple machines, so
* This code is only enabled on powerpc. --gcl
*/
ranges = of_get_property(parent, rprop, &rlen);
if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
pr_debug("OF: no ranges; cannot translate\n");
return 1;
}
if (ranges == NULL || rlen == 0) {
offset = of_read_number(addr, na);
memset(addr, 0, pna * 4);
pr_debug("OF: empty ranges; 1:1 translation\n");
goto finish;
}
pr_debug("OF: walking ranges...\n");
/* Now walk through the ranges */
rlen /= 4;
rone = na + pna + ns;
for (; rlen >= rone; rlen -= rone, ranges += rone) {
offset = bus->map(addr, ranges, na, ns, pna);
if (offset != OF_BAD_ADDR)
break;
}
if (offset == OF_BAD_ADDR) {
pr_debug("OF: not found !\n");
return 1;
}
memcpy(addr, ranges + na, 4 * pna);
finish:
of_dump_addr("OF: parent translation for:", addr, pna);
pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
/* Translate it into parent bus space */
return pbus->translate(addr, offset, pna);
}
/*
* Translate an address from the device-tree into a CPU physical address,
* this walks up the tree and applies the various bus mappings on the
* way.
*
* Note: We consider that crossing any level with #size-cells == 0 to mean
* that translation is impossible (that is we are not dealing with a value
* that can be mapped to a cpu physical address). This is not really specified
* that way, but this is traditionally the way IBM at least do things
*/
static u64 __of_translate_address(struct device_node *dev,
const __be32 *in_addr, const char *rprop)
{
struct device_node *parent = NULL;
struct of_bus *bus, *pbus;
__be32 addr[OF_MAX_ADDR_CELLS];
int na, ns, pna, pns;
u64 result = OF_BAD_ADDR;
pr_debug("OF: ** translation for device %s **\n", of_node_full_name(dev));
/* Increase refcount at current level */
of_node_get(dev);
/* Get parent & match bus type */
parent = of_get_parent(dev);
if (parent == NULL)
goto bail;
bus = of_match_bus(parent);
/* Count address cells & copy address locally */
bus->count_cells(dev, &na, &ns);
if (!OF_CHECK_COUNTS(na, ns)) {
pr_debug("OF: Bad cell count for %s\n", of_node_full_name(dev));
goto bail;
}
memcpy(addr, in_addr, na * 4);
pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
bus->name, na, ns, of_node_full_name(parent));
of_dump_addr("OF: translating address:", addr, na);
/* Translate */
for (;;) {
/* Switch to parent bus */
of_node_put(dev);
dev = parent;
parent = of_get_parent(dev);
/* If root, we have finished */
if (parent == NULL) {
pr_debug("OF: reached root node\n");
result = of_read_number(addr, na);
break;
}
/* Get new parent bus and counts */
pbus = of_match_bus(parent);
pbus->count_cells(dev, &pna, &pns);
if (!OF_CHECK_COUNTS(pna, pns)) {
printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
of_node_full_name(dev));
break;
}
pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
pbus->name, pna, pns, of_node_full_name(parent));
/* Apply bus translation */
if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
break;
/* Complete the move up one level */
na = pna;
ns = pns;
bus = pbus;
of_dump_addr("OF: one level translation:", addr, na);
}
bail:
of_node_put(parent);
of_node_put(dev);
return result;
}
u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
{
return __of_translate_address(dev, in_addr, "ranges");
}
EXPORT_SYMBOL(of_translate_address);
u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
{
return __of_translate_address(dev, in_addr, "dma-ranges");
}
EXPORT_SYMBOL(of_translate_dma_address);
const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
unsigned int *flags)
{
const __be32 *prop;
unsigned int psize;
struct device_node *parent;
struct of_bus *bus;
int onesize, i, na, ns;
/* Get parent & match bus type */
parent = of_get_parent(dev);
if (parent == NULL)
return NULL;
bus = of_match_bus(parent);
bus->count_cells(dev, &na, &ns);
of_node_put(parent);
if (!OF_CHECK_ADDR_COUNT(na))
return NULL;
/* Get "reg" or "assigned-addresses" property */
prop = of_get_property(dev, bus->addresses, &psize);
if (prop == NULL)
return NULL;
psize /= 4;
onesize = na + ns;
for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
if (i == index) {
if (size)
*size = of_read_number(prop + na, ns);
if (flags)
*flags = bus->get_flags(prop);
return prop;
}
return NULL;
}
EXPORT_SYMBOL(of_get_address);
#ifdef PCI_IOBASE
struct io_range {
struct list_head list;
phys_addr_t start;
resource_size_t size;
};
static LIST_HEAD(io_range_list);
static DEFINE_SPINLOCK(io_range_lock);
#endif
/*
* Record the PCI IO range (expressed as CPU physical address + size).
* Return a negative value if an error has occured, zero otherwise
*/
int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
{
int err = 0;
#ifdef PCI_IOBASE
struct io_range *range;
resource_size_t allocated_size = 0;
/* check if the range hasn't been previously recorded */
spin_lock(&io_range_lock);
list_for_each_entry(range, &io_range_list, list) {
if (addr >= range->start && addr + size <= range->start + size) {
/* range already registered, bail out */
goto end_register;
}
allocated_size += range->size;
}
/* range not registed yet, check for available space */
if (allocated_size + size - 1 > IO_SPACE_LIMIT) {
/* if it's too big check if 64K space can be reserved */
if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) {
err = -E2BIG;
goto end_register;
}
size = SZ_64K;
pr_warn("Requested IO range too big, new size set to 64K\n");
}
/* add the range to the list */
range = kzalloc(sizeof(*range), GFP_ATOMIC);
if (!range) {
err = -ENOMEM;
goto end_register;
}
range->start = addr;
range->size = size;
list_add_tail(&range->list, &io_range_list);
end_register:
spin_unlock(&io_range_lock);
#endif
return err;
}
phys_addr_t pci_pio_to_address(unsigned long pio)
{
phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
#ifdef PCI_IOBASE
struct io_range *range;
resource_size_t allocated_size = 0;
if (pio > IO_SPACE_LIMIT)
return address;
spin_lock(&io_range_lock);
list_for_each_entry(range, &io_range_list, list) {
if (pio >= allocated_size && pio < allocated_size + range->size) {
address = range->start + pio - allocated_size;
break;
}
allocated_size += range->size;
}
spin_unlock(&io_range_lock);
#endif
return address;
}
unsigned long __weak pci_address_to_pio(phys_addr_t address)
{
#ifdef PCI_IOBASE
struct io_range *res;
resource_size_t offset = 0;
unsigned long addr = -1;
spin_lock(&io_range_lock);
list_for_each_entry(res, &io_range_list, list) {
if (address >= res->start && address < res->start + res->size) {
addr = address - res->start + offset;
break;
}
offset += res->size;
}
spin_unlock(&io_range_lock);
return addr;
#else
if (address > IO_SPACE_LIMIT)
return (unsigned long)-1;
return (unsigned long) address;
#endif
}
static int __of_address_to_resource(struct device_node *dev,
const __be32 *addrp, u64 size, unsigned int flags,
const char *name, struct resource *r)
{
u64 taddr;
if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
return -EINVAL;
taddr = of_translate_address(dev, addrp);
if (taddr == OF_BAD_ADDR)
return -EINVAL;
memset(r, 0, sizeof(struct resource));
if (flags & IORESOURCE_IO) {
unsigned long port;
port = pci_address_to_pio(taddr);
if (port == (unsigned long)-1)
return -EINVAL;
r->start = port;
r->end = port + size - 1;
} else {
r->start = taddr;
r->end = taddr + size - 1;
}
r->flags = flags;
r->name = name ? name : dev->full_name;
return 0;
}
/**
* of_address_to_resource - Translate device tree address and return as resource
*
* Note that if your address is a PIO address, the conversion will fail if
* the physical address can't be internally converted to an IO token with
* pci_address_to_pio(), that is because it's either called to early or it
* can't be matched to any host bridge IO space
*/
int of_address_to_resource(struct device_node *dev, int index,
struct resource *r)
{
const __be32 *addrp;
u64 size;
unsigned int flags;
const char *name = NULL;
addrp = of_get_address(dev, index, &size, &flags);
if (addrp == NULL)
return -EINVAL;
/* Get optional "reg-names" property to add a name to a resource */
of_property_read_string_index(dev, "reg-names", index, &name);
return __of_address_to_resource(dev, addrp, size, flags, name, r);
}
EXPORT_SYMBOL_GPL(of_address_to_resource);
struct device_node *of_find_matching_node_by_address(struct device_node *from,
const struct of_device_id *matches,
u64 base_address)
{
struct device_node *dn = of_find_matching_node(from, matches);
struct resource res;
while (dn) {
if (!of_address_to_resource(dn, 0, &res) &&
res.start == base_address)
return dn;
dn = of_find_matching_node(dn, matches);
}
return NULL;
}
/**
* of_iomap - Maps the memory mapped IO for a given device_node
* @device: the device whose io range will be mapped
* @index: index of the io range
*
* Returns a pointer to the mapped memory
*/
void __iomem *of_iomap(struct device_node *np, int index)
{
struct resource res;
if (of_address_to_resource(np, index, &res))
return NULL;
return ioremap(res.start, resource_size(&res));
}
EXPORT_SYMBOL(of_iomap);
/*
* of_io_request_and_map - Requests a resource and maps the memory mapped IO
* for a given device_node
* @device: the device whose io range will be mapped
* @index: index of the io range
* @name: name of the resource
*
* Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
* error code on failure. Usage example:
*
* base = of_io_request_and_map(node, 0, "foo");
* if (IS_ERR(base))
* return PTR_ERR(base);
*/
void __iomem *of_io_request_and_map(struct device_node *np, int index,
const char *name)
{
struct resource res;
void __iomem *mem;
if (of_address_to_resource(np, index, &res))
return IOMEM_ERR_PTR(-EINVAL);
if (!request_mem_region(res.start, resource_size(&res), name))
return IOMEM_ERR_PTR(-EBUSY);
mem = ioremap(res.start, resource_size(&res));
if (!mem) {
release_mem_region(res.start, resource_size(&res));
return IOMEM_ERR_PTR(-ENOMEM);
}
return mem;
}
EXPORT_SYMBOL(of_io_request_and_map);
/**
* of_dma_get_range - Get DMA range info
* @np: device node to get DMA range info
* @dma_addr: pointer to store initial DMA address of DMA range
* @paddr: pointer to store initial CPU address of DMA range
* @size: pointer to store size of DMA range
*
* Look in bottom up direction for the first "dma-ranges" property
* and parse it.
* dma-ranges format:
* DMA addr (dma_addr) : naddr cells
* CPU addr (phys_addr_t) : pna cells
* size : nsize cells
*
* It returns -ENODEV if "dma-ranges" property was not found
* for this device in DT.
*/
int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
{
struct device_node *node = of_node_get(np);
const __be32 *ranges = NULL;
int len, naddr, nsize, pna;
int ret = 0;
u64 dmaaddr;
if (!node)
return -EINVAL;
while (1) {
naddr = of_n_addr_cells(node);
nsize = of_n_size_cells(node);
node = of_get_next_parent(node);
if (!node)
break;
ranges = of_get_property(node, "dma-ranges", &len);
/* Ignore empty ranges, they imply no translation required */
if (ranges && len > 0)
break;
/*
* At least empty ranges has to be defined for parent node if
* DMA is supported
*/
if (!ranges)
break;
}
if (!ranges) {
pr_debug("%s: no dma-ranges found for node(%s)\n",
__func__, np->full_name);
ret = -ENODEV;
goto out;
}
len /= sizeof(u32);
pna = of_n_addr_cells(node);
/* dma-ranges format:
* DMA addr : naddr cells
* CPU addr : pna cells
* size : nsize cells
*/
dmaaddr = of_read_number(ranges, naddr);
*paddr = of_translate_dma_address(np, ranges);
if (*paddr == OF_BAD_ADDR) {
pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n",
__func__, dma_addr, np->full_name);
ret = -EINVAL;
goto out;
}
*dma_addr = dmaaddr;
*size = of_read_number(ranges + naddr + pna, nsize);
pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
*dma_addr, *paddr, *size);
out:
of_node_put(node);
return ret;
}
EXPORT_SYMBOL_GPL(of_dma_get_range);
/**
* of_dma_is_coherent - Check if device is coherent
* @np: device node
*
* It returns true if "dma-coherent" property was found
* for this device in DT.
*/
bool of_dma_is_coherent(struct device_node *np)
{
struct device_node *node = of_node_get(np);
while (node) {
if (of_property_read_bool(node, "dma-coherent")) {
of_node_put(node);
return true;
}
node = of_get_next_parent(node);
}
of_node_put(node);
return false;
}
EXPORT_SYMBOL_GPL(of_dma_is_coherent);