--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Texas Instruments System Control Interface Protocol Driver
+ * Based on drivers/firmware/ti_sci.c from Linux.
+ *
+ * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Lokesh Vutla <lokeshvutla@ti.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <mailbox.h>
+#include <dm/device.h>
+#include <linux/err.h>
+#include <linux/soc/ti/k3-sec-proxy.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+
+#include "ti_sci.h"
+
+/* List of all TI SCI devices active in system */
+static LIST_HEAD(ti_sci_list);
+
+/**
+ * struct ti_sci_xfer - Structure representing a message flow
+ * @tx_message: Transmit message
+ * @rx_len: Receive message length
+ */
+struct ti_sci_xfer {
+ struct k3_sec_proxy_msg tx_message;
+ u8 rx_len;
+};
+
+/**
+ * struct ti_sci_desc - Description of SoC integration
+ * @host_id: Host identifier representing the compute entity
+ * @max_rx_timeout_us: Timeout for communication with SoC (in Microseconds)
+ * @max_msg_size: Maximum size of data per message that can be handled.
+ */
+struct ti_sci_desc {
+ u8 host_id;
+ int max_rx_timeout_us;
+ int max_msg_size;
+};
+
+/**
+ * struct ti_sci_info - Structure representing a TI SCI instance
+ * @dev: Device pointer
+ * @desc: SoC description for this instance
+ * @handle: Instance of TI SCI handle to send to clients.
+ * @chan_tx: Transmit mailbox channel
+ * @chan_rx: Receive mailbox channel
+ * @xfer: xfer info
+ * @list: list head
+ * @is_secure: Determines if the communication is through secure threads.
+ * @host_id: Host identifier representing the compute entity
+ * @seq: Seq id used for verification for tx and rx message.
+ */
+struct ti_sci_info {
+ struct udevice *dev;
+ const struct ti_sci_desc *desc;
+ struct ti_sci_handle handle;
+ struct mbox_chan chan_tx;
+ struct mbox_chan chan_rx;
+ struct mbox_chan chan_notify;
+ struct ti_sci_xfer xfer;
+ struct list_head list;
+ bool is_secure;
+ u8 host_id;
+ u8 seq;
+};
+
+#define handle_to_ti_sci_info(h) container_of(h, struct ti_sci_info, handle)
+
+/**
+ * ti_sci_setup_one_xfer() - Setup one message type
+ * @info: Pointer to SCI entity information
+ * @msg_type: Message type
+ * @msg_flags: Flag to set for the message
+ * @buf: Buffer to be send to mailbox channel
+ * @tx_message_size: transmit message size
+ * @rx_message_size: receive message size
+ *
+ * Helper function which is used by various command functions that are
+ * exposed to clients of this driver for allocating a message traffic event.
+ *
+ * Return: Corresponding ti_sci_xfer pointer if all went fine,
+ * else appropriate error pointer.
+ */
+static struct ti_sci_xfer *ti_sci_setup_one_xfer(struct ti_sci_info *info,
+ u16 msg_type, u32 msg_flags,
+ u32 *buf,
+ size_t tx_message_size,
+ size_t rx_message_size)
+{
+ struct ti_sci_xfer *xfer = &info->xfer;
+ struct ti_sci_msg_hdr *hdr;
+
+ /* Ensure we have sane transfer sizes */
+ if (rx_message_size > info->desc->max_msg_size ||
+ tx_message_size > info->desc->max_msg_size ||
+ rx_message_size < sizeof(*hdr) || tx_message_size < sizeof(*hdr))
+ return ERR_PTR(-ERANGE);
+
+ info->seq = ~info->seq;
+ xfer->tx_message.buf = buf;
+ xfer->tx_message.len = tx_message_size;
+ xfer->rx_len = (u8)rx_message_size;
+
+ hdr = (struct ti_sci_msg_hdr *)buf;
+ hdr->seq = info->seq;
+ hdr->type = msg_type;
+ hdr->host = info->host_id;
+ hdr->flags = msg_flags;
+
+ return xfer;
+}
+
+/**
+ * ti_sci_get_response() - Receive response from mailbox channel
+ * @info: Pointer to SCI entity information
+ * @xfer: Transfer to initiate and wait for response
+ * @chan: Channel to receive the response
+ *
+ * Return: -ETIMEDOUT in case of no response, if transmit error,
+ * return corresponding error, else if all goes well,
+ * return 0.
+ */
+static inline int ti_sci_get_response(struct ti_sci_info *info,
+ struct ti_sci_xfer *xfer,
+ struct mbox_chan *chan)
+{
+ struct k3_sec_proxy_msg *msg = &xfer->tx_message;
+ struct ti_sci_secure_msg_hdr *secure_hdr;
+ struct ti_sci_msg_hdr *hdr;
+ int ret;
+
+ /* Receive the response */
+ ret = mbox_recv(chan, msg, info->desc->max_rx_timeout_us);
+ if (ret) {
+ dev_err(info->dev, "%s: Message receive failed. ret = %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ /* ToDo: Verify checksum */
+ if (info->is_secure) {
+ secure_hdr = (struct ti_sci_secure_msg_hdr *)msg->buf;
+ msg->buf = (u32 *)((void *)msg->buf + sizeof(*secure_hdr));
+ }
+
+ /* msg is updated by mailbox driver */
+ hdr = (struct ti_sci_msg_hdr *)msg->buf;
+
+ /* Sanity check for message response */
+ if (hdr->seq != info->seq) {
+ dev_dbg(info->dev, "%s: Message for %d is not expected\n",
+ __func__, hdr->seq);
+ return ret;
+ }
+
+ if (msg->len > info->desc->max_msg_size) {
+ dev_err(info->dev, "%s: Unable to handle %zu xfer (max %d)\n",
+ __func__, msg->len, info->desc->max_msg_size);
+ return -EINVAL;
+ }
+
+ if (msg->len < xfer->rx_len) {
+ dev_err(info->dev, "%s: Recv xfer %zu < expected %d length\n",
+ __func__, msg->len, xfer->rx_len);
+ }
+
+ return ret;
+}
+
+/**
+ * ti_sci_do_xfer() - Do one transfer
+ * @info: Pointer to SCI entity information
+ * @xfer: Transfer to initiate and wait for response
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static inline int ti_sci_do_xfer(struct ti_sci_info *info,
+ struct ti_sci_xfer *xfer)
+{
+ struct k3_sec_proxy_msg *msg = &xfer->tx_message;
+ u8 secure_buf[info->desc->max_msg_size];
+ struct ti_sci_secure_msg_hdr secure_hdr;
+ int ret;
+
+ if (info->is_secure) {
+ /* ToDo: get checksum of the entire message */
+ secure_hdr.checksum = 0;
+ secure_hdr.reserved = 0;
+ memcpy(&secure_buf[sizeof(secure_hdr)], xfer->tx_message.buf,
+ xfer->tx_message.len);
+
+ xfer->tx_message.buf = (u32 *)secure_buf;
+ xfer->tx_message.len += sizeof(secure_hdr);
+ xfer->rx_len += sizeof(secure_hdr);
+ }
+
+ /* Send the message */
+ ret = mbox_send(&info->chan_tx, msg);
+ if (ret) {
+ dev_err(info->dev, "%s: Message sending failed. ret = %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return ti_sci_get_response(info, xfer, &info->chan_rx);
+}
+
+/**
+ * ti_sci_cmd_get_revision() - command to get the revision of the SCI entity
+ * @handle: pointer to TI SCI handle
+ *
+ * Updates the SCI information in the internal data structure.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_get_revision(struct ti_sci_handle *handle)
+{
+ struct ti_sci_msg_resp_version *rev_info;
+ struct ti_sci_version_info *ver;
+ struct ti_sci_msg_hdr hdr;
+ struct ti_sci_info *info;
+ struct ti_sci_xfer *xfer;
+ int ret;
+
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ if (!handle)
+ return -EINVAL;
+
+ info = handle_to_ti_sci_info(handle);
+
+ xfer = ti_sci_setup_one_xfer(info, TI_SCI_MSG_VERSION, 0x0,
+ (u32 *)&hdr, sizeof(struct ti_sci_msg_hdr),
+ sizeof(*rev_info));
+ if (IS_ERR(xfer)) {
+ ret = PTR_ERR(xfer);
+ dev_err(info->dev, "Message alloc failed(%d)\n", ret);
+ return ret;
+ }
+
+ ret = ti_sci_do_xfer(info, xfer);
+ if (ret) {
+ dev_err(info->dev, "Mbox communication fail %d\n", ret);
+ return ret;
+ }
+
+ rev_info = (struct ti_sci_msg_resp_version *)xfer->tx_message.buf;
+
+ ver = &handle->version;
+ ver->abi_major = rev_info->abi_major;
+ ver->abi_minor = rev_info->abi_minor;
+ ver->firmware_revision = rev_info->firmware_revision;
+ strncpy(ver->firmware_description, rev_info->firmware_description,
+ sizeof(ver->firmware_description));
+
+ return 0;
+}
+
+/**
+ * ti_sci_is_response_ack() - Generic ACK/NACK message checkup
+ * @r: pointer to response buffer
+ *
+ * Return: true if the response was an ACK, else returns false.
+ */
+static inline bool ti_sci_is_response_ack(void *r)
+{
+ struct ti_sci_msg_hdr *hdr = r;
+
+ return hdr->flags & TI_SCI_FLAG_RESP_GENERIC_ACK ? true : false;
+}
+
+/**
+ * ti_sci_get_handle_from_sysfw() - Get the TI SCI handle of the SYSFW
+ * @dev: Pointer to the SYSFW device
+ *
+ * Return: pointer to handle if successful, else EINVAL if invalid conditions
+ * are encountered.
+ */
+const
+struct ti_sci_handle *ti_sci_get_handle_from_sysfw(struct udevice *sci_dev)
+{
+ if (!sci_dev)
+ return ERR_PTR(-EINVAL);
+
+ struct ti_sci_info *info = dev_get_priv(sci_dev);
+
+ if (!info)
+ return ERR_PTR(-EINVAL);
+
+ struct ti_sci_handle *handle = &info->handle;
+
+ if (!handle)
+ return ERR_PTR(-EINVAL);
+
+ return handle;
+}
+
+/**
+ * ti_sci_get_handle() - Get the TI SCI handle for a device
+ * @dev: Pointer to device for which we want SCI handle
+ *
+ * Return: pointer to handle if successful, else EINVAL if invalid conditions
+ * are encountered.
+ */
+const struct ti_sci_handle *ti_sci_get_handle(struct udevice *dev)
+{
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ struct udevice *sci_dev = dev_get_parent(dev);
+
+ return ti_sci_get_handle_from_sysfw(sci_dev);
+}
+
+/**
+ * ti_sci_get_by_phandle() - Get the TI SCI handle using DT phandle
+ * @dev: device node
+ * @propname: property name containing phandle on TISCI node
+ *
+ * Return: pointer to handle if successful, else appropriate error value.
+ */
+const struct ti_sci_handle *ti_sci_get_by_phandle(struct udevice *dev,
+ const char *property)
+{
+ struct ti_sci_info *entry, *info = NULL;
+ u32 phandle, err;
+ ofnode node;
+
+ err = ofnode_read_u32(dev_ofnode(dev), property, &phandle);
+ if (err)
+ return ERR_PTR(err);
+
+ node = ofnode_get_by_phandle(phandle);
+ if (!ofnode_valid(node))
+ return ERR_PTR(-EINVAL);
+
+ list_for_each_entry(entry, &ti_sci_list, list)
+ if (ofnode_equal(dev_ofnode(entry->dev), node)) {
+ info = entry;
+ break;
+ }
+
+ if (!info)
+ return ERR_PTR(-ENODEV);
+
+ return &info->handle;
+}
+
+/**
+ * ti_sci_of_to_info() - generate private data from device tree
+ * @dev: corresponding system controller interface device
+ * @info: pointer to driver specific private data
+ *
+ * Return: 0 if all goes good, else appropriate error message.
+ */
+static int ti_sci_of_to_info(struct udevice *dev, struct ti_sci_info *info)
+{
+ int ret;
+
+ ret = mbox_get_by_name(dev, "tx", &info->chan_tx);
+ if (ret) {
+ dev_err(dev, "%s: Acquiring Tx channel failed. ret = %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = mbox_get_by_name(dev, "rx", &info->chan_rx);
+ if (ret) {
+ dev_err(dev, "%s: Acquiring Rx channel failed. ret = %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ /* Notify channel is optional. Enable only if populated */
+ ret = mbox_get_by_name(dev, "notify", &info->chan_notify);
+ if (ret) {
+ dev_dbg(dev, "%s: Acquiring notify channel failed. ret = %d\n",
+ __func__, ret);
+ }
+
+ info->host_id = dev_read_u32_default(dev, "ti,host-id",
+ info->desc->host_id);
+
+ info->is_secure = dev_read_bool(dev, "ti,secure-host");
+
+ return 0;
+}
+
+/**
+ * ti_sci_probe() - Basic probe
+ * @dev: corresponding system controller interface device
+ *
+ * Return: 0 if all goes good, else appropriate error message.
+ */
+static int ti_sci_probe(struct udevice *dev)
+{
+ struct ti_sci_info *info;
+ int ret;
+
+ debug("%s(dev=%p)\n", __func__, dev);
+
+ info = dev_get_priv(dev);
+ info->desc = (void *)dev_get_driver_data(dev);
+
+ ret = ti_sci_of_to_info(dev, info);
+ if (ret) {
+ dev_err(dev, "%s: Probe failed with error %d\n", __func__, ret);
+ return ret;
+ }
+
+ info->dev = dev;
+ info->seq = 0xA;
+
+ list_add_tail(&info->list, &ti_sci_list);
+
+ ret = ti_sci_cmd_get_revision(&info->handle);
+
+ return ret;
+}
+
+/* Description for AM654 */
+static const struct ti_sci_desc ti_sci_sysfw_am654_desc = {
+ .host_id = 4,
+ .max_rx_timeout_us = 1000000,
+ .max_msg_size = 60,
+};
+
+static const struct udevice_id ti_sci_ids[] = {
+ {
+ .compatible = "ti,k2g-sci",
+ .data = (ulong)&ti_sci_sysfw_am654_desc
+ },
+ { /* Sentinel */ },
+};
+
+U_BOOT_DRIVER(ti_sci) = {
+ .name = "ti_sci",
+ .id = UCLASS_FIRMWARE,
+ .of_match = ti_sci_ids,
+ .probe = ti_sci_probe,
+ .priv_auto_alloc_size = sizeof(struct ti_sci_info),
+};