From: Thierry Reding treding@nvidia.com
This function generates a new, unused phandle by looking up the highest phandle value stored in a device tree and adding one.
Signed-off-by: Thierry Reding treding@nvidia.com --- Changes in v2: - rename to fdtdec_generate_phandle()
include/fdtdec.h | 12 ++++++++++++ lib/fdtdec.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+)
diff --git a/include/fdtdec.h b/include/fdtdec.h index a0ba57c6318b..b593c562584d 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -981,6 +981,18 @@ int fdtdec_setup_mem_size_base(void); */ int fdtdec_setup_memory_banksize(void);
+/** + * fdtdec_generate_phandle() - return a new, unused phandle for an FDT blob + * + * Returns a phandle that can be used to refer to a new device tree node. It + * is one higher than the currently highest phandle in the given FDT blob. + * + * @param blob FDT blob + * @param maxp return location for the new phandle + * @return 0 on success or a negative error code on failure + */ +int fdtdec_generate_phandle(const void *blob, uint32_t *phandle); + /** * Set up the device tree ready for use */ diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 09a7e133a539..d384c84feb33 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -1243,6 +1243,34 @@ __weak void *board_fdt_blob_setup(void) } #endif
+int fdtdec_generate_phandle(const void *blob, uint32_t *phandle) +{ + uint32_t max = 0; + int offset = -1; + + while (true) { + uint32_t value; + + offset = fdt_next_node(blob, offset, NULL); + if (offset < 0) { + if (offset == -FDT_ERR_NOTFOUND) + break; + + return offset; + } + + value = fdt_get_phandle(blob, offset); + + if (value > max) + max = value; + } + + if (phandle) + *phandle = max + 1; + + return 0; +} + int fdtdec_setup(void) { #if CONFIG_IS_ENABLED(OF_CONTROL)