From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: [PATCH v5 3/8] libfdt: Add max phandle retrieval function Date: Fri, 29 Jul 2016 11:55:46 +0200 Message-ID: <20160729095551.13592-4-maxime.ripard@free-electrons.com> References: <20160729095551.13592-1-maxime.ripard@free-electrons.com> Return-path: In-Reply-To: <20160729095551.13592-1-maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> Sender: devicetree-compiler-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: David Gibson Cc: Pantelis Antoniou , Simon Glass , Boris Brezillon , Alexander Kaplan , Thomas Petazzoni , devicetree-compiler-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, =?UTF-8?q?Antoine=20T=C3=A9nart?= , Stefan Agner , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Maxime Ripard List-Id: devicetree@vger.kernel.org Add a function to retrieve the highest phandle in a given device tree. Acked-by: Simon Glass Reviewed-by: Stefan Agner Reviewed-by: David Gibson Signed-off-by: Maxime Ripard --- libfdt/fdt_ro.c | 26 ++++++++++++++++++++++++++ libfdt/libfdt.h | 15 +++++++++++++++ tests/get_phandle.c | 6 ++++++ 3 files changed, 47 insertions(+) diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c index 50cce864283c..04590984bd51 100644 --- a/libfdt/fdt_ro.c +++ b/libfdt/fdt_ro.c @@ -88,6 +88,32 @@ static int _fdt_string_eq(const void *fdt, int stroffset, return (strlen(p) == 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 (uint32_t)-1; + + phandle = fdt_get_phandle(fdt, offset); + if (phandle == (uint32_t)-1) + continue; + + 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); diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h index be109a8aac84..06b84cc16bbf 100644 --- a/libfdt/libfdt.h +++ b/libfdt/libfdt.h @@ -286,6 +286,21 @@ 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. This will ignore badly formatted phandles, or phandles + * with a value of 0 or -1. + * + * returns: + * the highest phandle on success + * 0, if no phandle was found in the device tree + * -1, 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/tests/get_phandle.c b/tests/get_phandle.c index 2079591d4c49..22bd7b81b3f0 100644 --- a/tests/get_phandle.c +++ b/tests/get_phandle.c @@ -44,6 +44,7 @@ static void check_phandle(void *fdt, const char *path, uint32_t checkhandle) int main(int argc, char *argv[]) { + uint32_t max; void *fdt; test_init(argc, argv); @@ -53,5 +54,10 @@ int main(int argc, char *argv[]) check_phandle(fdt, "/subnode@2", PHANDLE_1); check_phandle(fdt, "/subnode@2/subsubnode@0", PHANDLE_2); + max = fdt_get_max_phandle(fdt); + if (max != PHANDLE_2) + FAIL("fdt_get_max_phandle returned 0x%x instead of 0x%x\n", + max, PHANDLE_2); + PASS(); } -- 2.9.2