Received-SPF: pass (google.com: domain of linux-kernel+bounces-38929-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
From: Alexandru Elisei <alexandru.elisei@arm.com>
To: catalin.marinas@arm.com,
	will@kernel.org,
	oliver.upton@linux.dev,
	maz@kernel.org,
	james.morse@arm.com,
	suzuki.poulose@arm.com,
	yuzenghui@huawei.com,
	arnd@arndb.de,
	akpm@linux-foundation.org,
	mingo@redhat.com,
	peterz@infradead.org,
	juri.lelli@redhat.com,
	vincent.guittot@linaro.org,
	dietmar.eggemann@arm.com,
	rostedt@goodmis.org,
	bsegall@google.com,
	mgorman@suse.de,
	bristot@redhat.com,
	vschneid@redhat.com,
	mhiramat@kernel.org,
	rppt@kernel.org,
	hughd@google.com
Cc: pcc@google.com,
	steven.price@arm.com,
	anshuman.khandual@arm.com,
	vincenzo.frascino@arm.com,
	david@redhat.com,
	eugenis@google.com,
	kcc@google.com,
	hyesoo.yu@samsung.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	kvmarm@lists.linux.dev,
	linux-fsdevel@vger.kernel.org,
	linux-arch@vger.kernel.org,
	linux-mm@kvack.org,
	linux-trace-kernel@vger.kernel.org
Subject: [PATCH RFC v3 15/35] of: fdt: Add of_flat_read_u32()
Date: Thu, 25 Jan 2024 16:42:36 +0000
Message-Id: <20240125164256.4147-16-alexandru.elisei@arm.com>
In-Reply-To: <20240125164256.4147-1-alexandru.elisei@arm.com>
References: <20240125164256.4147-1-alexandru.elisei@arm.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

Add the function of_flat_read_u32() to return the value of a property as
an u32.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
---

Changes since rfc v2:

* New patch, suggested by Rob Herring.

 drivers/of/fdt.c       | 21 +++++++++++++++++++++
 include/linux/of_fdt.h |  2 ++
 2 files changed, 23 insertions(+)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index bf502ba8da95..dfcd79fd5fd9 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -755,6 +755,27 @@ const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
 	return fdt_getprop(initial_boot_params, node, name, size);
 }
 
+/*
+ * of_flat_read_u32 - Return the value of the given property as an u32.
+ *
+ * @node: device node from which the property value is to be read
+ * @propname: name of the property
+ * @out_value: the value of the property
+ * @return: 0 on success, -EINVAL if property does not exist
+ */
+int __init of_flat_read_u32(unsigned long node, const char *propname,
+			    u32 *out_value)
+{
+	const __be32 *reg;
+
+	reg = of_get_flat_dt_prop(node, propname, NULL);
+	if (!reg)
+		return -EINVAL;
+
+	*out_value = be32_to_cpup(reg);
+	return 0;
+}
+
 /**
  * of_fdt_is_compatible - Return true if given node from the given blob has
  * compat in its compatible list
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 0e26f8c3b10e..d7901699061b 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -57,6 +57,8 @@ extern const void *of_get_flat_dt_prop(unsigned long node, const char *name,
 extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
 extern unsigned long of_get_flat_dt_root(void);
 extern uint32_t of_get_flat_dt_phandle(unsigned long node);
+extern int of_flat_read_u32(unsigned long node, const char *propname,
+			    u32 *out_value);
 
 extern int early_init_dt_scan_chosen(char *cmdline);
 extern int early_init_dt_scan_memory(void);
-- 
2.43.0