feat(drivers/arm/mhu): add MHU driver
The Arm Message Handling Unit (MHU) is a mailbox controller used to
communicate with other processing element(s). Adding a driver to
enable the communication:
- Adding generic MHU driver interface,
- Adding MHU_v2_x driver.
Driver supports:
- Discovering available MHU channels,
- Sending / receiving words over MHU channels,
- Signaling happens over a dedicated channel.
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Signed-off-by: David Vincze <david.vincze@arm.com>
Change-Id: I41a5b968f6b8319cdbdf7907d70bd8837839862e
diff --git a/drivers/arm/mhu/mhu_v2_x.h b/drivers/arm/mhu/mhu_v2_x.h
new file mode 100644
index 0000000..10247d2
--- /dev/null
+++ b/drivers/arm/mhu/mhu_v2_x.h
@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2020-2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MHU_V2_X_H
+#define MHU_V2_X_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#define MHU_2_X_INTR_NR2R_OFF (0x0u)
+#define MHU_2_X_INTR_R2NR_OFF (0x1u)
+#define MHU_2_1_INTR_CHCOMB_OFF (0x2u)
+
+#define MHU_2_X_INTR_NR2R_MASK (0x1u << MHU_2_X_INTR_NR2R_OFF)
+#define MHU_2_X_INTR_R2NR_MASK (0x1u << MHU_2_X_INTR_R2NR_OFF)
+#define MHU_2_1_INTR_CHCOMB_MASK (0x1u << MHU_2_1_INTR_CHCOMB_OFF)
+
+enum mhu_v2_x_frame_t {
+ MHU_V2_X_SENDER_FRAME = 0x0u,
+ MHU_V2_X_RECEIVER_FRAME = 0x1u,
+};
+
+enum mhu_v2_x_supported_revisions {
+ MHU_REV_READ_FROM_HW = 0,
+ MHU_REV_2_0,
+ MHU_REV_2_1,
+};
+
+struct mhu_v2_x_dev_t {
+ uintptr_t base;
+ enum mhu_v2_x_frame_t frame;
+ uint32_t subversion; /*!< Hardware subversion: v2.X */
+ bool is_initialized; /*!< Indicates if the MHU driver
+ * is initialized and enabled
+ */
+};
+
+/**
+ * MHU v2 error enumeration types.
+ */
+enum mhu_v2_x_error_t {
+ MHU_V_2_X_ERR_NONE = 0,
+ MHU_V_2_X_ERR_NOT_INIT = -1,
+ MHU_V_2_X_ERR_ALREADY_INIT = -2,
+ MHU_V_2_X_ERR_UNSUPPORTED_VERSION = -3,
+ MHU_V_2_X_ERR_INVALID_ARG = -4,
+ MHU_V_2_X_ERR_GENERAL = -5
+};
+
+/**
+ * Initializes the driver.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * rev MHU revision (if can't be identified from HW).
+ *
+ * Reads the MHU hardware version.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * MHU revision only has to be specified when versions can't be read
+ * from HW (ARCH_MAJOR_REV reg reads as 0x0).
+ *
+ * This function doesn't check if dev is NULL.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_driver_init(struct mhu_v2_x_dev_t *dev,
+ enum mhu_v2_x_supported_revisions rev);
+
+/**
+ * Returns the number of channels implemented.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ *
+ * This function doesn't check if dev is NULL.
+ */
+uint32_t mhu_v2_x_get_num_channel_implemented(
+ const struct mhu_v2_x_dev_t *dev);
+
+/**
+ * Sends the value over a channel.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Channel to send the value over.
+ * val Value to send.
+ *
+ * Sends the value over a channel.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_send(const struct mhu_v2_x_dev_t *dev,
+ uint32_t channel, uint32_t val);
+
+/**
+ * Polls sender channel status.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Channel to poll the status of.
+ * value Pointer to variable that will store the value.
+ *
+ * Polls sender channel status.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_poll(const struct mhu_v2_x_dev_t *dev,
+ uint32_t channel, uint32_t *value);
+
+/**
+ * Clears the channel after the value is send over it.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Channel to clear.
+ *
+ * Clears the channel after the value is send over it.
+ *
+ * Returns mhu_v2_x_error_t error code..
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_clear(const struct mhu_v2_x_dev_t *dev,
+ uint32_t channel);
+
+/**
+ * Receives the value over a channel.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Channel to receive the value from.
+ * value Pointer to variable that will store the value.
+ *
+ * Receives the value over a channel.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_receive(
+ const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t *value);
+
+/**
+ * Sets bits in the Channel Mask.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Which channel's mask to set.
+ * mask Mask to be set over a receiver frame.
+ *
+ * Sets bits in the Channel Mask.
+ *
+ * Returns mhu_v2_x_error_t error code..
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_mask_set(
+ const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t mask);
+
+/**
+ * Clears bits in the Channel Mask.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ * channel Which channel's mask to clear.
+ * mask Mask to be clear over a receiver frame.
+ *
+ * Clears bits in the Channel Mask.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ * This function doesn't check if channel is implemented.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_channel_mask_clear(
+ const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t mask);
+
+/**
+ * Initiates a MHU transfer with the handshake signals.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ *
+ * Initiates a MHU transfer with the handshake signals in a blocking mode.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_initiate_transfer(
+ const struct mhu_v2_x_dev_t *dev);
+
+/**
+ * Closes a MHU transfer with the handshake signals.
+ *
+ * dev MHU device struct mhu_v2_x_dev_t.
+ *
+ * Closes a MHU transfer with the handshake signals in a blocking mode.
+ *
+ * Returns mhu_v2_x_error_t error code.
+ *
+ * This function doesn't check if dev is NULL.
+ */
+enum mhu_v2_x_error_t mhu_v2_x_close_transfer(
+ const struct mhu_v2_x_dev_t *dev);
+
+#endif /* MHU_V2_X_H */