[PATCH V2 2/4] firmware: xilinx: Add ZynqMP RSA API for RSA encrypt/decrypt operation

[Harsha Harsha <harsha.harsha@amd.com>]

Add zynqmp_pm_rsa API in the ZynqMP firmware to encrypt and decrypt
the datai using RSA hardware engine for ZynqMP.

Signed-off-by: Harsha Harsha <harsha.harsha@amd.com>
Co-developed-by: Dhaval Shah <dhaval.r.shah@amd.com>
Signed-off-by: Dhaval Shah <dhaval.r.shah@amd.com>
---
 drivers/firmware/xilinx/zynqmp.c     | 21 +++++++++++++++++++++
 include/linux/firmware/xlnx-zynqmp.h |  8 ++++++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 10ae42a2ae22..d6f73823bab4 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -1426,6 +1426,27 @@ int zynqmp_pm_sha_hash(const u64 address, const u32 size, const u32 flags)
 }
 EXPORT_SYMBOL_GPL(zynqmp_pm_sha_hash);
 
+/**
+ * zynqmp_pm_rsa - Access RSA hardware to encrypt/decrypt the data with RSA.
+ * @address:	Address of the data
+ * @size:	Size of the data.
+ * @flags:
+ *		BIT(0) - Encryption/Decryption
+ *			 0 - RSA decryption with private key
+ *			 1 - RSA encryption with public key.
+ *
+ * Return:	Returns status, either success or error code.
+ */
+int zynqmp_pm_rsa(const u64 address, const u32 size, const u32 flags)
+{
+	u32 lower_32_bits = lower_32_bits(address);
+	u32 upper_32_bits = upper_32_bits(address);
+
+	return zynqmp_pm_invoke_fn(PM_SECURE_RSA, upper_32_bits, lower_32_bits,
+				   size, flags, NULL);
+}
+EXPORT_SYMBOL_GPL(zynqmp_pm_rsa);
+
 /**
  * zynqmp_pm_register_notifier() - PM API for register a subsystem
  *                                to be notified about specific
diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
index cd5acfa29cbc..8666b0c3cd66 100644
--- a/include/linux/firmware/xlnx-zynqmp.h
+++ b/include/linux/firmware/xlnx-zynqmp.h
@@ -117,6 +117,7 @@ enum pm_api_id {
 	PM_FPGA_GET_STATUS = 23,
 	PM_GET_CHIPID = 24,
 	PM_SECURE_SHA = 26,
+	PM_SECURE_RSA = 27,
 	PM_PINCTRL_REQUEST = 28,
 	PM_PINCTRL_RELEASE = 29,
 	PM_PINCTRL_GET_FUNCTION = 30,
@@ -542,6 +543,7 @@ int zynqmp_pm_set_requirement(const u32 node, const u32 capabilities,
 			      const enum zynqmp_pm_request_ack ack);
 int zynqmp_pm_aes_engine(const u64 address, u32 *out);
 int zynqmp_pm_sha_hash(const u64 address, const u32 size, const u32 flags);
+int zynqmp_pm_rsa(const u64 address, const u32 size, const u32 flags);
 int zynqmp_pm_fpga_load(const u64 address, const u32 size, const u32 flags);
 int zynqmp_pm_fpga_get_status(u32 *value);
 int zynqmp_pm_write_ggs(u32 index, u32 value);
@@ -744,6 +746,12 @@ static inline int zynqmp_pm_sha_hash(const u64 address, const u32 size,
 	return -ENODEV;
 }
 
+static inline int zynqmp_pm_rsa(const u64 address, const u32 size,
+				const u32 flags)
+{
+	return -ENODEV;
+}
+
 static inline int zynqmp_pm_fpga_load(const u64 address, const u32 size,
 				      const u32 flags)
 {
-- 
2.36.1