firmware: xilinx: Add ZynqMP efuse access API

Add zynqmp_pm_efuse_access API in the ZynqMP
firmware for read/write access of efuse memory.
Signed-off-by: Praveen Teja Kundanala <praveen.teja.kundanala@amd.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240224114516.86365-6-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/firmware/xilinx/zynqmp.c

@@ -3,6 +3,7 @@
  * Xilinx Zynq MPSoC Firmware layer
  *
  *  Copyright (C) 2014-2022 Xilinx, Inc.
+ *  Copyright (C) 2022 - 2023, Advanced Micro Devices, Inc.
  *
  *  Michal Simek <michal.simek@amd.com>
  *  Davorin Mista <davorin.mista@aggios.com>
@@ -1384,6 +1385,30 @@ int zynqmp_pm_aes_engine(const u64 address, u32 *out)
 }
 EXPORT_SYMBOL_GPL(zynqmp_pm_aes_engine);
 
+/**
+ * zynqmp_pm_efuse_access - Provides access to efuse memory.
+ * @address:	Address of the efuse params structure
+ * @out:		Returned output value
+ *
+ * Return:	Returns status, either success or error code.
+ */
+int zynqmp_pm_efuse_access(const u64 address, u32 *out)
+{
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+	int ret;
+
+	if (!out)
+		return -EINVAL;
+
+	ret = zynqmp_pm_invoke_fn(PM_EFUSE_ACCESS, ret_payload, 2,
+				  upper_32_bits(address),
+				  lower_32_bits(address));
+	*out = ret_payload[1];
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(zynqmp_pm_efuse_access);
+
 /**
  * zynqmp_pm_sha_hash - Access the SHA engine to calculate the hash
  * @address:	Address of the data/ Address of output buffer where

include/linux/firmware/xlnx-zynqmp.h

@@ -3,6 +3,7 @@
  * Xilinx Zynq MPSoC Firmware layer
  *
  *  Copyright (C) 2014-2021 Xilinx
+ *  Copyright (C) 2022 - 2023, Advanced Micro Devices, Inc.
  *
  *  Michal Simek <michal.simek@amd.com>
  *  Davorin Mista <davorin.mista@aggios.com>
@@ -171,6 +172,7 @@ enum pm_api_id {
 	PM_CLOCK_GETPARENT = 44,
 	PM_FPGA_READ = 46,
 	PM_SECURE_AES = 47,
+	PM_EFUSE_ACCESS = 53,
 	PM_FEATURE_CHECK = 63,
 };
 
@@ -562,6 +564,7 @@ int zynqmp_pm_set_requirement(const u32 node, const u32 capabilities,
 			      const u32 qos,
 			      const enum zynqmp_pm_request_ack ack);
 int zynqmp_pm_aes_engine(const u64 address, u32 *out);
+int zynqmp_pm_efuse_access(const u64 address, u32 *out);
 int zynqmp_pm_sha_hash(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);
@@ -749,6 +752,11 @@ static inline int zynqmp_pm_aes_engine(const u64 address, u32 *out)
 	return -ENODEV;
 }
 
+static inline int zynqmp_pm_efuse_access(const u64 address, u32 *out)
+{
+	return -ENODEV;
+}
+
 static inline int zynqmp_pm_sha_hash(const u64 address, const u32 size,
 				     const u32 flags)
 {