| Message ID | 20160705082646.25044-7-maxime.ripard@free-electrons.com |
|---|---|
| State | Accepted |
| Delegated to: | Tom Rini |
| Headers | show |
On Tue, Jul 05, 2016 at 10:26:39AM +0200, Maxime Ripard wrote: > Add a function to retrieve the highest phandle in a given device tree. > > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > Reviewed-by: Stefan Agner <stefan@agner.ch> > Acked-by: Simon Glass <sjg@chromium.org> > --- > include/libfdt.h | 13 +++++++++++++ > lib/libfdt/fdt_ro.c | 26 ++++++++++++++++++++++++++ > 2 files changed, 39 insertions(+) > > diff --git a/include/libfdt.h b/include/libfdt.h > index fbbe58ceb3f1..4643be5adf39 100644 > --- a/include/libfdt.h > +++ b/include/libfdt.h > @@ -283,6 +283,19 @@ int fdt_move(const void *fdt, void *buf, int bufsize); > */ > const char *fdt_string(const void *fdt, int stroffset); > > +/** > + * fdt_get_max_phandle - retrieves the highest phandle in a tree > + * @fdt: pointer to the device tree blob > + * > + * fdt_get_max_phandle retrieves the highest phandle in the given > + * device tree > + * > + * returns: > + * the highest phandle on success > + * 0, if an error occurred This will also return 0 if there are no phandles in the entire tree, which isn't exactly an error. > + */ > +uint32_t fdt_get_max_phandle(const void *fdt); > + > /** > * fdt_num_mem_rsv - retrieve the number of memory reserve map entries > * @fdt: pointer to the device tree blob > diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c > index 12214c2dc2b5..503150ef1dc5 100644 > --- a/lib/libfdt/fdt_ro.c > +++ b/lib/libfdt/fdt_ro.c > @@ -47,6 +47,32 @@ static int _fdt_string_eq(const void *fdt, int stroffset, > return (strnlen(p, len + 1) == len) && (memcmp(p, s, len) == 0); > } > > +uint32_t fdt_get_max_phandle(const void *fdt) > +{ > + uint32_t max_phandle = 0; > + int offset; > + > + for (offset = fdt_next_node(fdt, -1, NULL);; > + offset = fdt_next_node(fdt, offset, NULL)) { > + uint32_t phandle; > + > + if (offset == -FDT_ERR_NOTFOUND) > + return max_phandle; > + > + if (offset < 0) > + return 0; > + > + phandle = fdt_get_phandle(fdt, offset); > + if (phandle == (uint32_t)-1) > + return 0; It might be worth pointing out that *any* -1 phandle in the tree counts as an error. Since -1 phandles are sometimes used as a placeholder, ignoring them might be a better option. > + if (phandle > max_phandle) > + max_phandle = phandle; > + } > + > + return 0; > +} > + > int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size) > { > FDT_CHECK_HEADER(fdt);
On Tue, Jul 05, 2016 at 10:26:39AM +0200, Maxime Ripard wrote: > Add a function to retrieve the highest phandle in a given device tree. > > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > Reviewed-by: Stefan Agner <stefan@agner.ch> > Acked-by: Simon Glass <sjg@chromium.org> Applied to u-boot/master, thanks!
diff --git a/include/libfdt.h b/include/libfdt.h index fbbe58ceb3f1..4643be5adf39 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -283,6 +283,19 @@ int fdt_move(const void *fdt, void *buf, int bufsize); */ const char *fdt_string(const void *fdt, int stroffset); +/** + * fdt_get_max_phandle - retrieves the highest phandle in a tree + * @fdt: pointer to the device tree blob + * + * fdt_get_max_phandle retrieves the highest phandle in the given + * device tree + * + * returns: + * the highest phandle on success + * 0, if an error occurred + */ +uint32_t fdt_get_max_phandle(const void *fdt); + /** * fdt_num_mem_rsv - retrieve the number of memory reserve map entries * @fdt: pointer to the device tree blob diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c index 12214c2dc2b5..503150ef1dc5 100644 --- a/lib/libfdt/fdt_ro.c +++ b/lib/libfdt/fdt_ro.c @@ -47,6 +47,32 @@ static int _fdt_string_eq(const void *fdt, int stroffset, return (strnlen(p, len + 1) == len) && (memcmp(p, s, len) == 0); } +uint32_t fdt_get_max_phandle(const void *fdt) +{ + uint32_t max_phandle = 0; + int offset; + + for (offset = fdt_next_node(fdt, -1, NULL);; + offset = fdt_next_node(fdt, offset, NULL)) { + uint32_t phandle; + + if (offset == -FDT_ERR_NOTFOUND) + return max_phandle; + + if (offset < 0) + return 0; + + phandle = fdt_get_phandle(fdt, offset); + if (phandle == (uint32_t)-1) + return 0; + + if (phandle > max_phandle) + max_phandle = phandle; + } + + return 0; +} + int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size) { FDT_CHECK_HEADER(fdt);