1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/firmware/arm-ffa/arm-ffa.c b/drivers/firmware/arm-ffa/arm-ffa.c
new file mode 100644
index 00000000000..68df75bd9e5
--- /dev/null
+++ b/drivers/firmware/arm-ffa/arm-ffa.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2022-2023 Arm Limited and/or its affiliates <open-source-office@arm.com>
+ *
+ * Authors:
+ *   Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
+ */
+
+#include <common.h>
+#include <arm_ffa.h>
+#include <arm_ffa_priv.h>
+#include <dm.h>
+#include <log.h>
+#include <asm/global_data.h>
+#include <dm/device-internal.h>
+#include <linux/errno.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/**
+ * invoke_ffa_fn() - SMC wrapper
+ * @args: FF-A ABI arguments to be copied to Xn registers
+ * @res: FF-A ABI return data to be copied from Xn registers
+ *
+ * Calls low level SMC assembly function
+ */
+void invoke_ffa_fn(ffa_value_t args, ffa_value_t *res)
+{
+	arm_smccc_1_2_smc(&args, res);
+}
+
+/**
+ * arm_ffa_discover() - perform FF-A discovery
+ * @dev: The Arm FF-A bus device (arm_ffa)
+ * Try to discover the FF-A framework. Discovery is performed by
+ * querying the FF-A framework version from secure world using the FFA_VERSION ABI.
+ * Return:
+ *
+ * true on success. Otherwise, false.
+ */
+static bool arm_ffa_discover(struct udevice *dev)
+{
+	int ret;
+
+	log_info("Arm FF-A framework discovery\n");
+
+	ret = ffa_get_version_hdlr(dev);
+	if (ret)
+		return false;
+
+	return true;
+}
+
+/**
+ * arm_ffa_is_supported() - FF-A bus discovery callback
+ * @invoke_fn: legacy SMC invoke function (not used)
+ *
+ * Perform FF-A discovery by calling arm_ffa_discover().
+ * Discovery is performed by querying the FF-A framework version from
+ * secure world using the FFA_VERSION ABI.
+ *
+ * The FF-A driver is registered as an SMCCC feature driver. So, features discovery
+ * callbacks are called by the PSCI driver (PSCI device is the SMCCC features
+ * root device).
+ *
+ * The FF-A driver supports the SMCCCv1.2 extended input/output registers.
+ * So, the legacy SMC invocation is not used.
+ *
+ * Return:
+ *
+ * 0 on success. Otherwise, failure
+ */
+static bool arm_ffa_is_supported(void (*invoke_fn)(ulong a0, ulong a1,
+						   ulong a2, ulong a3,
+						   ulong a4, ulong a5,
+						   ulong a6, ulong a7,
+						   struct arm_smccc_res *res))
+{
+	return arm_ffa_discover(NULL);
+}
+
+/* Arm FF-A driver operations */
+
+static const struct ffa_bus_ops ffa_ops = {
+	.partition_info_get = ffa_get_partitions_info_hdlr,
+	.sync_send_receive = ffa_msg_send_direct_req_hdlr,
+	.rxtx_unmap = ffa_unmap_rxtx_buffers_hdlr,
+};
+
+/* Registering the FF-A driver as an SMCCC feature driver */
+
+ARM_SMCCC_FEATURE_DRIVER(arm_ffa) = {
+	.driver_name = FFA_DRV_NAME,
+	.is_supported = arm_ffa_is_supported,
+};
+
+/* Declaring the FF-A driver under UCLASS_FFA */
+
+U_BOOT_DRIVER(arm_ffa) = {
+	.name		= FFA_DRV_NAME,
+	.id		= UCLASS_FFA,
+	.flags		= DM_REMOVE_OS_PREPARE,
+	.ops		= &ffa_ops,
+};