diff options
Diffstat (limited to 'pbl/fdt.c')
-rw-r--r-- | pbl/fdt.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/pbl/fdt.c b/pbl/fdt.c new file mode 100644 index 0000000000..b4a40a514b --- /dev/null +++ b/pbl/fdt.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/libfdt.h> +#include <pbl.h> +#include <printk.h> + +void fdt_find_mem(const void *fdt, unsigned long *membase, unsigned long *memsize) +{ + const __be32 *nap, *nsp, *reg; + uint32_t na, ns; + uint64_t memsize64, membase64; + int node, size, i; + + /* Make sure FDT blob is sane */ + if (fdt_check_header(fdt) != 0) { + pr_err("Invalid device tree blob\n"); + goto err; + } + + /* Find the #address-cells and #size-cells properties */ + node = fdt_path_offset(fdt, "/"); + if (node < 0) { + pr_err("Cannot find root node\n"); + goto err; + } + + nap = fdt_getprop(fdt, node, "#address-cells", &size); + if (!nap || (size != 4)) { + pr_err("Cannot find #address-cells property"); + goto err; + } + na = fdt32_to_cpu(*nap); + + nsp = fdt_getprop(fdt, node, "#size-cells", &size); + if (!nsp || (size != 4)) { + pr_err("Cannot find #size-cells property"); + goto err; + } + ns = fdt32_to_cpu(*nap); + + /* Find the memory range */ + node = fdt_node_offset_by_prop_value(fdt, -1, "device_type", + "memory", sizeof("memory")); + if (node < 0) { + pr_err("Cannot find memory node\n"); + goto err; + } + + reg = fdt_getprop(fdt, node, "reg", &size); + if (size < (na + ns) * sizeof(u32)) { + pr_err("cannot get memory range\n"); + goto err; + } + + membase64 = 0; + for (i = 0; i < na; i++) + membase64 = (membase64 << 32) | fdt32_to_cpu(*reg++); + + /* get the memsize and truncate it to under 4G on 32 bit machines */ + memsize64 = 0; + for (i = 0; i < ns; i++) + memsize64 = (memsize64 << 32) | fdt32_to_cpu(*reg++); + + *membase = membase64; + *memsize = memsize64; + + return; +err: + pr_err("No memory, cannot continue\n"); + while (1); +} |