blob: 409d18bedbba6fa78a52855b88fc3ee9b10a020a [file] [log] [blame]
/*
* Copyright (C) 2014, Red Hat Inc, Andrew Jones <drjones@redhat.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.
*/
#include "libcflat.h"
#include "libfdt/libfdt.h"
#include "devicetree.h"
static const void *fdt;
const void *dt_fdt(void)
{
return fdt;
}
bool dt_available(void)
{
return fdt_check_header(fdt) == 0;
}
int dt_get_nr_cells(int fdtnode, u32 *nr_address_cells, u32 *nr_size_cells)
{
const struct fdt_property *prop;
u32 *nr_cells;
int len, nac, nsc;
prop = fdt_get_property(fdt, fdtnode, "#address-cells", &len);
if (prop == NULL)
return len;
nr_cells = (u32 *)prop->data;
nac = fdt32_to_cpu(*nr_cells);
prop = fdt_get_property(fdt, fdtnode, "#size-cells", &len);
if (prop == NULL)
return len;
nr_cells = (u32 *)prop->data;
nsc = fdt32_to_cpu(*nr_cells);
*nr_address_cells = nac;
*nr_size_cells = nsc;
return 0;
}
void dt_reg_init(struct dt_reg *reg, u32 nr_address_cells, u32 nr_size_cells)
{
memset(reg, 0, sizeof(struct dt_reg));
reg->nr_address_cells = nr_address_cells;
reg->nr_size_cells = nr_size_cells;
}
int dt_get_reg(int fdtnode, int regidx, struct dt_reg *reg)
{
const struct fdt_property *prop;
u32 *cells, i;
unsigned nr_tuple_cells;
int len;
prop = fdt_get_property(fdt, fdtnode, "reg", &len);
if (prop == NULL)
return len;
cells = (u32 *)prop->data;
nr_tuple_cells = reg->nr_address_cells + reg->nr_size_cells;
regidx *= nr_tuple_cells;
if (regidx + nr_tuple_cells > len/sizeof(u32))
return -FDT_ERR_NOTFOUND;
for (i = 0; i < reg->nr_address_cells; ++i)
reg->address_cells[i] = fdt32_to_cpu(cells[regidx + i]);
regidx += reg->nr_address_cells;
for (i = 0; i < reg->nr_size_cells; ++i)
reg->size_cells[i] = fdt32_to_cpu(cells[regidx + i]);
return 0;
}
int dt_pbus_translate_node(int fdtnode, int regidx,
struct dt_pbus_reg *pbus_reg)
{
struct dt_reg raw_reg;
u32 nac, nsc;
int parent, ret;
parent = fdt_parent_offset(fdt, fdtnode);
if (parent < 0)
return parent;
ret = dt_get_nr_cells(parent, &nac, &nsc);
if (ret != 0)
return ret;
dt_reg_init(&raw_reg, nac, nsc);
ret = dt_get_reg(fdtnode, regidx, &raw_reg);
if (ret < 0)
return ret;
pbus_reg->addr = dt_pbus_read_cells(raw_reg.nr_address_cells,
raw_reg.address_cells);
pbus_reg->size = dt_pbus_read_cells(raw_reg.nr_size_cells,
raw_reg.size_cells);
return 0;
}
int dt_pbus_translate(const struct dt_device *dev, int regidx,
void *reg)
{
return dt_pbus_translate_node(dev->fdtnode, regidx, reg);
}
int dt_bus_match_any(const struct dt_device *dev __unused, int fdtnode)
{
/* matches any device with a valid node */
return fdtnode < 0 ? fdtnode : 1;
}
static const struct dt_bus dt_default_bus = {
.match = dt_bus_match_any,
.translate = dt_pbus_translate,
};
void dt_bus_init_defaults(struct dt_bus *bus)
{
memcpy(bus, &dt_default_bus, sizeof(struct dt_bus));
}
void dt_device_init(struct dt_device *dev, const struct dt_bus *bus,
void *info)
{
memset(dev, 0, sizeof(struct dt_device));
dev->bus = bus;
dev->info = info;
}
int dt_device_find_compatible(const struct dt_device *dev,
const char *compatible)
{
int node, ret;
node = fdt_node_offset_by_compatible(fdt, -1, compatible);
while (node >= 0) {
ret = dev->bus->match(dev, node);
if (ret < 0)
return ret;
else if (ret)
break;
node = fdt_node_offset_by_compatible(fdt, node, compatible);
}
return node;
}
int dt_pbus_get_base_compatible(const char *compatible,
struct dt_pbus_reg *base)
{
struct dt_device dev;
int node;
dt_device_init(&dev, &dt_default_bus, NULL);
node = dt_device_find_compatible(&dev, compatible);
if (node < 0)
return node;
dt_device_bind_node(&dev, node);
return dt_pbus_get_base(&dev, base);
}
int dt_get_memory_params(struct dt_pbus_reg *regs, int nr_regs)
{
const char *pn = "device_type", *pv = "memory";
int node, ret, reg_idx, pl = strlen(pv) + 1, nr = 0;
struct dt_pbus_reg reg;
node = fdt_node_offset_by_prop_value(fdt, -1, pn, pv, pl);
while (node >= 0) {
reg_idx = 0;
while (nr < nr_regs) {
ret = dt_pbus_translate_node(node, reg_idx, &reg);
if (ret == -FDT_ERR_NOTFOUND)
break;
if (ret < 0)
return ret;
regs[nr].addr = reg.addr;
regs[nr].size = reg.size;
++nr, ++reg_idx;
}
node = fdt_node_offset_by_prop_value(fdt, node, pn, pv, pl);
}
return node != -FDT_ERR_NOTFOUND ? node : nr;
}
int dt_for_each_cpu_node(void (*func)(int fdtnode, u64 regval, void *info),
void *info)
{
const struct fdt_property *prop;
int cpus, cpu, ret, len;
struct dt_reg raw_reg;
u32 nac, nsc;
u64 regval;
cpus = fdt_path_offset(fdt, "/cpus");
if (cpus < 0)
return cpus;
ret = dt_get_nr_cells(cpus, &nac, &nsc);
if (ret < 0)
return ret;
dt_reg_init(&raw_reg, nac, nsc);
dt_for_each_subnode(cpus, cpu) {
prop = fdt_get_property(fdt, cpu, "device_type", &len);
if (prop == NULL)
continue;
if (len != 4 || strcmp((char *)prop->data, "cpu"))
continue;
ret = dt_get_reg(cpu, 0, &raw_reg);
if (ret < 0)
return ret;
regval = raw_reg.address_cells[0];
if (nac == 2)
regval = (regval << 32) | raw_reg.address_cells[1];
func(cpu, regval, info);
}
return 0;
}
int dt_get_bootargs(const char **bootargs)
{
const struct fdt_property *prop;
int node, len;
*bootargs = NULL;
node = fdt_path_offset(fdt, "/chosen");
if (node < 0)
return node;
prop = fdt_get_property(fdt, node, "bootargs", &len);
if (!prop)
return len;
*bootargs = prop->data;
return 0;
}
int dt_get_default_console_node(void)
{
const char *p, *q;
int node, len;
node = fdt_path_offset(fdt, "/chosen");
if (node < 0)
return node;
p = fdt_getprop(fdt, node, "stdout-path", &len);
if (!p) {
p = fdt_getprop(fdt, node, "linux,stdout-path", &len);
if (!p)
return len;
}
q = strchrnul(p, ':');
len = q - p;
return fdt_path_offset_namelen(fdt, p, len);
}
int dt_get_initrd(const char **initrd, u32 *size)
{
const struct fdt_property *prop;
const char *start, *end;
int node, len;
u32 *data;
*initrd = NULL;
*size = 0;
node = fdt_path_offset(fdt, "/chosen");
if (node < 0)
return node;
prop = fdt_get_property(fdt, node, "linux,initrd-start", &len);
if (!prop)
return len;
data = (u32 *)prop->data;
start = (const char *)(unsigned long)fdt32_to_cpu(*data);
prop = fdt_get_property(fdt, node, "linux,initrd-end", &len);
if (!prop) {
assert(len != -FDT_ERR_NOTFOUND);
return len;
}
data = (u32 *)prop->data;
end = (const char *)(unsigned long)fdt32_to_cpu(*data);
*initrd = start;
*size = (unsigned long)end - (unsigned long)start;
return 0;
}
int dt_init(const void *fdt_ptr)
{
int ret;
ret = fdt_check_header(fdt_ptr);
if (ret < 0)
return ret;
/* Sanity check the path. */
ret = fdt_path_offset(fdt_ptr, "/");
if (ret < 0)
return ret;
fdt = fdt_ptr;
return 0;
}