DM: crypto/rsa_mod_exp: Add rsa Modular Exponentiation DM driver

Add a new rsa uclass for performing modular exponentiation and implement
the software driver basing on this uclass.

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
CC: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/crypto/Makefile

@@ -6,4 +6,5 @@
 #
 
 obj-$(CONFIG_EXYNOS_ACE_SHA)	+= ace_sha.o
+obj-y += rsa_mod_exp/
 obj-y += fsl/

drivers/crypto/rsa_mod_exp/Kconfig

@@ -0,0 +1,5 @@
+config DM_MOD_EXP
+	bool "Enable Driver Model for RSA Modular Exponentiation"
+	depends on DM
+	help
+	  If you want to use driver model for RSA Modular Exponentiation, say Y.

drivers/crypto/rsa_mod_exp/Makefile

@@ -0,0 +1,7 @@
+#
+# (C) Copyright 2014 Freescale Semiconductor, Inc.
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-$(CONFIG_RSA) += mod_exp_uclass.o mod_exp_sw.o

drivers/crypto/rsa_mod_exp/mod_exp_sw.c

@@ -0,0 +1,39 @@
+/*
+ * (C) Copyright 2014 Freescale Semiconductor, Inc.
+ * Author: Ruchika Gupta <ruchika.gupta@freescale.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+#include <common.h>
+#include <dm.h>
+#include <u-boot/rsa-mod-exp.h>
+
+int mod_exp_sw(struct udevice *dev, const uint8_t *sig, uint32_t sig_len,
+		struct key_prop *prop, uint8_t *out)
+{
+	int ret = 0;
+
+	ret = rsa_mod_exp_sw(sig, sig_len, prop, out);
+	if (ret) {
+		debug("%s: RSA failed to verify: %d\n", __func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct mod_exp_ops mod_exp_ops_sw = {
+	.mod_exp	= mod_exp_sw,
+};
+
+U_BOOT_DRIVER(mod_exp_sw) = {
+	.name	= "mod_exp_sw",
+	.id	= UCLASS_MOD_EXP,
+	.ops	= &mod_exp_ops_sw,
+};
+
+U_BOOT_DEVICE(mod_exp_sw) = {
+	.name = "mod_exp_sw",
+};

drivers/crypto/rsa_mod_exp/mod_exp_uclass.c

@@ -0,0 +1,31 @@
+/*
+ * (C) Copyright 2014 Freescale Semiconductor, Inc
+ * Author: Ruchika Gupta <ruchika.gupta@freescale.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <u-boot/rsa-mod-exp.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <malloc.h>
+#include <asm/io.h>
+#include <linux/list.h>
+
+int rsa_mod_exp(struct udevice *dev, const uint8_t *sig, uint32_t sig_len,
+		struct key_prop *node, uint8_t *out)
+{
+	const struct mod_exp_ops *ops = device_get_ops(dev);
+
+	if (!ops->mod_exp)
+		return -ENOSYS;
+
+	return ops->mod_exp(dev, sig, sig_len, node, out);
+}
+
+UCLASS_DRIVER(mod_exp) = {
+	.id		= UCLASS_MOD_EXP,
+	.name		= "rsa_mod_exp",
+};