[RFC PATCH 4/4] drivers: crypto: add software ecdsa support

[Philippe Reynes]

Add an software ecdsa driver so it is
now possible to use ecdsa signature on
board without ecdsa hardware support.

Signed-off-by: Philippe Reynes <philippe.reynes at softathome.com>
---
 drivers/crypto/Kconfig          |  2 ++
 drivers/crypto/Makefile         |  1 +
 drivers/crypto/ecdsa/Kconfig    |  6 ++++++
 drivers/crypto/ecdsa/Makefile   |  6 ++++++
 drivers/crypto/ecdsa/ecdsa-sw.c | 33 +++++++++++++++++++++++++++++++++
 5 files changed, 48 insertions(+)
 create mode 100644 drivers/crypto/ecdsa/Kconfig
 create mode 100644 drivers/crypto/ecdsa/Makefile
 create mode 100644 drivers/crypto/ecdsa/ecdsa-sw.c

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 0d58e3910fe..cf49e5c0f7e 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -12,4 +12,6 @@ source "drivers/crypto/nuvoton/Kconfig"
 
 source "drivers/crypto/tegra/Kconfig"
 
+source "drivers/crypto/ecdsa/Kconfig"
+
 endmenu
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index e4a4482b7f3..8170e4cae9c 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -4,6 +4,7 @@
 #	http://www.samsung.com
 
 obj-$(CONFIG_EXYNOS_ACE_SHA)	+= ace_sha.o
+obj-$(CONFIG_ECDSA) += ecdsa/
 obj-y += aes/
 obj-y += rsa_mod_exp/
 obj-y += fsl/
diff --git a/drivers/crypto/ecdsa/Kconfig b/drivers/crypto/ecdsa/Kconfig
new file mode 100644
index 00000000000..308824d8421
--- /dev/null
+++ b/drivers/crypto/ecdsa/Kconfig
@@ -0,0 +1,6 @@
+config ECDSA_SW
+	bool "Enable driver for ECDSA in software"
+	depends on ECDSA_MBEDTLS
+	help
+	  Enable driver for ECDSA operations in software. Currently
+	  it supports multiple ECDSA algorithm.
diff --git a/drivers/crypto/ecdsa/Makefile b/drivers/crypto/ecdsa/Makefile
new file mode 100644
index 00000000000..8f9e5a767f8
--- /dev/null
+++ b/drivers/crypto/ecdsa/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (C) 2026 Philippe Reynes <philippe.reynes at softathome.com>
+#
+
+obj-$(CONFIG_ECDSA_SW) += ecdsa-sw.o
diff --git a/drivers/crypto/ecdsa/ecdsa-sw.c b/drivers/crypto/ecdsa/ecdsa-sw.c
new file mode 100644
index 00000000000..0d526371ecb
--- /dev/null
+++ b/drivers/crypto/ecdsa/ecdsa-sw.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2026 Philippe Reynes <philippe.reynes at softathome.com>
+ */
+#include <dm/device.h>
+#include <linux/types.h>
+#include <u-boot/ecdsa.h>
+#include <crypto/ecdsa-uclass.h>
+#include <dm/platdata.h>
+#include <crypto/internal/sw_ecdsa.h>
+
+static int ops_sw_ecdsa_verify(__always_unused struct udevice *dev,
+			       const struct ecdsa_public_key *pubkey,
+			       const void *hash, size_t hash_len,
+			       const void *signature, size_t sig_len)
+{
+	return sw_ecdsa_verify(pubkey, hash, hash_len, signature, sig_len);
+}
+
+static const struct ecdsa_ops sw_ecdsa_ops = {
+	.verify = ops_sw_ecdsa_verify,
+};
+
+U_BOOT_DRIVER(sw_ecdsa) = {
+	.name	= "sw_ecdsa",
+	.id	= UCLASS_ECDSA,
+	.ops	= &sw_ecdsa_ops,
+	.flags	= DM_FLAG_PRE_RELOC,
+};
+
+U_BOOT_DRVINFO(sw_ecdsa) = {
+	.name = "sw_ecdsa",
+};
-- 
2.43.0