The /memory device tree bindings allow to store the ECC detection and
correction bits through the ecc-detection-bits and ecc-correction-bits
properties.
Our next patches rely on whether ECC is enabled, so let's add a helper
to retrieve the ECC correction bits from the /memory node.
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
include/linux/of.h | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/include/linux/of.h b/include/linux/of.h
index a0bedd038a05..2fbee65a7aa9 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -1510,10 +1510,35 @@ static inline int of_get_available_child_count(const struct device_node *np)
num++;
return num;
}
+/**
+ * of_memory_get_ecc_correction_bits() - Returns the number of ECC correction bits
+ *
+ * Search for the number of bits in memory that can be corrected by the
+ * ECC algorithm.
+ *
+ * Returns:
+ * The number of ECC bits, 0 if there's no ECC support, a negative error
+ * code on failure.
+ */
+static inline int of_memory_get_ecc_correction_bits(void)
+{
+ struct device_node *mem;
+ u32 val = 0;
+
+ mem = of_find_node_by_path("/memory");
+ if (!mem)
+ return -ENODEV;
+
+ of_property_read_u32(mem, "ecc-correction-bits", &val);
+ of_node_put(mem);
+
+ return val;
+}
+
#define _OF_DECLARE_STUB(table, name, compat, fn, fn_type) \
static const struct of_device_id __of_table_##name \
__attribute__((unused)) \
= { .compatible = compat, \
.data = (fn == (fn_type)NULL) ? fn : fn }
--
2.44.0
