Re: [RFC PATCH 2/6] firmware: xilinx: Add ZynqMP SHA API for SHA3 functionality

This patch adds zynqmp_pm_sha_hash API in the ZynqMP firmware to compute
SHA3 hash of given data.

Signed-off-by: Harsha <redacted>
---
  drivers/firmware/xilinx/zynqmp.c     | 26 ++++++++++++++++++++++++++
  include/linux/firmware/xlnx-zynqmp.h |  8 ++++++++
  2 files changed, 34 insertions(+)

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 3dd45a7..a84c5ea 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c

@@ -1117,6 +1117,32 @@ int zynqmp_pm_aes_engine(const u64 address, u32 *out)
  EXPORT_SYMBOL_GPL(zynqmp_pm_aes_engine);
  
  /**
+ * zynqmp_pm_sha_hash - Access the SHA engine to calculate the hash
+ * @address:	Address of the data/ Address of output buffer where
+ *		hash should be stored.
+ * @size:	Size of the data.
+ * @flags:
+ *	BIT(0) - for initializing csudma driver and SHA3(Here address
+ *		 and size inputs can be NULL).
+ *	BIT(1) - to call Sha3_Update API which can be called multiple
+ *		 times when data is not contiguous.
+ *	BIT(2) - to get final hash of the whole updated data.
+ *		 Hash will be overwritten at provided address with
+ *		 48 bytes.
+ *
+ * Return:	Returns status, either success or error code.
+ */
+int zynqmp_pm_sha_hash(const u64 address, const u32 size, const u32 flags)
+{
+	u32 lower_addr = lower_32_bits(address);
+	u32 upper_addr = upper_32_bits(address);
+
+	return zynqmp_pm_invoke_fn(PM_SECURE_SHA, upper_addr, lower_addr,
+				   size, flags, NULL);
+}
+EXPORT_SYMBOL_GPL(zynqmp_pm_sha_hash);
+
+/**
   * zynqmp_pm_system_shutdown - PM call to request a system shutdown or restart
   * @type:	Shutdown or restart? 0 for shutdown, 1 for restart
   * @subtype:	Specifies which system should be restarted or shut down

diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
index 47fd4e5..38ef708 100644
--- a/include/linux/firmware/xlnx-zynqmp.h
+++ b/include/linux/firmware/xlnx-zynqmp.h

@@ -78,6 +78,7 @@ enum pm_api_id {
  	PM_FPGA_LOAD = 22,
  	PM_FPGA_GET_STATUS = 23,
  	PM_GET_CHIPID = 24,
+	PM_SECURE_SHA = 26,
  	PM_PINCTRL_REQUEST = 28,
  	PM_PINCTRL_RELEASE = 29,
  	PM_PINCTRL_GET_FUNCTION = 30,

@@ -410,6 +411,7 @@ 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_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);
  int zynqmp_pm_write_ggs(u32 index, u32 value);

@@ -581,6 +583,12 @@ static inline int zynqmp_pm_aes_engine(const u64 address, u32 *out)
  	return -ENODEV;
  }
  
+static inline int zynqmp_pm_sha_hash(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)
  {