firmware: ti_sci: Add support for Device control

Texas Instrument's System Control Interface (TI-SCI) Message Protocol
is used in Texas Instrument's System on Chip (SoC) such as those
in keystone family K2G SoC to communicate between various compute
processors with a central system controller entity.

TI-SCI message protocol provides support for management of various
hardware entitites within the SoC. Add support driver to allow
communication with system controller entity within the SoC using the
mailbox client.

We introduce the fundamental device management capability support to
the driver protocol as part of this change.

[d-gerlach@ti.com: Contributed device reset handling]
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>

1 files changed, 433 insertions, 0 deletions

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 5e99d7c18276..c7b25ccf6f07 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -495,6 +495,437 @@ fail:
 }
 
 /**
+ * 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_set_device_state() - Set device state helper
+ * @handle:	pointer to TI SCI handle
+ * @id:		Device identifier
+ * @flags:	flags to setup for the device
+ * @state:	State to move the device to
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_set_device_state(const struct ti_sci_handle *handle,
+				   u32 id, u32 flags, u8 state)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_msg_req_set_device_state *req;
+	struct ti_sci_msg_hdr *resp;
+	struct ti_sci_xfer *xfer;
+	struct device *dev;
+	int ret = 0;
+
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+	if (!handle)
+		return -EINVAL;
+
+	info = handle_to_ti_sci_info(handle);
+	dev = info->dev;
+
+	xfer = ti_sci_get_one_xfer(info, TI_SCI_MSG_SET_DEVICE_STATE,
+				   flags | TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				   sizeof(*req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(dev, "Message alloc failed(%d)\n", ret);
+		return ret;
+	}
+	req = (struct ti_sci_msg_req_set_device_state *)xfer->xfer_buf;
+	req->id = id;
+	req->state = state;
+
+	ret = ti_sci_do_xfer(info, xfer);
+	if (ret) {
+		dev_err(dev, "Mbox send fail %d\n", ret);
+		goto fail;
+	}
+
+	resp = (struct ti_sci_msg_hdr *)xfer->xfer_buf;
+
+	ret = ti_sci_is_response_ack(resp) ? 0 : -ENODEV;
+
+fail:
+	ti_sci_put_one_xfer(&info->minfo, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_get_device_state() - Get device state helper
+ * @handle:	Handle to the device
+ * @id:		Device Identifier
+ * @clcnt:	Pointer to Context Loss Count
+ * @resets:	pointer to resets
+ * @p_state:	pointer to p_state
+ * @c_state:	pointer to c_state
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_get_device_state(const struct ti_sci_handle *handle,
+				   u32 id,  u32 *clcnt,  u32 *resets,
+				    u8 *p_state,  u8 *c_state)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_msg_req_get_device_state *req;
+	struct ti_sci_msg_resp_get_device_state *resp;
+	struct ti_sci_xfer *xfer;
+	struct device *dev;
+	int ret = 0;
+
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+	if (!handle)
+		return -EINVAL;
+
+	if (!clcnt && !resets && !p_state && !c_state)
+		return -EINVAL;
+
+	info = handle_to_ti_sci_info(handle);
+	dev = info->dev;
+
+	/* Response is expected, so need of any flags */
+	xfer = ti_sci_get_one_xfer(info, TI_SCI_MSG_GET_DEVICE_STATE,
+				   0, sizeof(*req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(dev, "Message alloc failed(%d)\n", ret);
+		return ret;
+	}
+	req = (struct ti_sci_msg_req_get_device_state *)xfer->xfer_buf;
+	req->id = id;
+
+	ret = ti_sci_do_xfer(info, xfer);
+	if (ret) {
+		dev_err(dev, "Mbox send fail %d\n", ret);
+		goto fail;
+	}
+
+	resp = (struct ti_sci_msg_resp_get_device_state *)xfer->xfer_buf;
+	if (!ti_sci_is_response_ack(resp)) {
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	if (clcnt)
+		*clcnt = resp->context_loss_count;
+	if (resets)
+		*resets = resp->resets;
+	if (p_state)
+		*p_state = resp->programmed_state;
+	if (c_state)
+		*c_state = resp->current_state;
+fail:
+	ti_sci_put_one_xfer(&info->minfo, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_cmd_get_device() - command to request for device managed by TISCI
+ * @handle:	Pointer to TISCI handle as retrieved by *ti_sci_get_handle
+ * @id:		Device Identifier
+ *
+ * Request for the device - NOTE: the client MUST maintain integrity of
+ * usage count by balancing get_device with put_device. No refcounting is
+ * managed by driver for that purpose.
+ *
+ * NOTE: The request is for exclusive access for the processor.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_get_device(const struct ti_sci_handle *handle, u32 id)
+{
+	return ti_sci_set_device_state(handle, id,
+				       MSG_FLAG_DEVICE_EXCLUSIVE,
+				       MSG_DEVICE_SW_STATE_ON);
+}
+
+/**
+ * ti_sci_cmd_idle_device() - Command to idle a device managed by TISCI
+ * @handle:	Pointer to TISCI handle as retrieved by *ti_sci_get_handle
+ * @id:		Device Identifier
+ *
+ * Request for the device - NOTE: the client MUST maintain integrity of
+ * usage count by balancing get_device with put_device. No refcounting is
+ * managed by driver for that purpose.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_idle_device(const struct ti_sci_handle *handle, u32 id)
+{
+	return ti_sci_set_device_state(handle, id,
+				       MSG_FLAG_DEVICE_EXCLUSIVE,
+				       MSG_DEVICE_SW_STATE_RETENTION);
+}
+
+/**
+ * ti_sci_cmd_put_device() - command to release a device managed by TISCI
+ * @handle:	Pointer to TISCI handle as retrieved by *ti_sci_get_handle
+ * @id:		Device Identifier
+ *
+ * Request for the device - NOTE: the client MUST maintain integrity of
+ * usage count by balancing get_device with put_device. No refcounting is
+ * managed by driver for that purpose.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_put_device(const struct ti_sci_handle *handle, u32 id)
+{
+	return ti_sci_set_device_state(handle, id,
+				       0, MSG_DEVICE_SW_STATE_AUTO_OFF);
+}
+
+/**
+ * ti_sci_cmd_dev_is_valid() - Is the device valid
+ * @handle:	Pointer to TISCI handle as retrieved by *ti_sci_get_handle
+ * @id:		Device Identifier
+ *
+ * Return: 0 if all went fine and the device ID is valid, else return
+ * appropriate error.
+ */
+static int ti_sci_cmd_dev_is_valid(const struct ti_sci_handle *handle, u32 id)
+{
+	u8 unused;
+
+	/* check the device state which will also tell us if the ID is valid */
+	return ti_sci_get_device_state(handle, id, NULL, NULL, NULL, &unused);
+}
+
+/**
+ * ti_sci_cmd_dev_get_clcnt() - Get context loss counter
+ * @handle:	Pointer to TISCI handle
+ * @id:		Device Identifier
+ * @count:	Pointer to Context Loss counter to populate
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_dev_get_clcnt(const struct ti_sci_handle *handle, u32 id,
+				    u32 *count)
+{
+	return ti_sci_get_device_state(handle, id, count, NULL, NULL, NULL);
+}
+
+/**
+ * ti_sci_cmd_dev_is_idle() - Check if the device is requested to be idle
+ * @handle:	Pointer to TISCI handle
+ * @id:		Device Identifier
+ * @r_state:	true if requested to be idle
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_dev_is_idle(const struct ti_sci_handle *handle, u32 id,
+				  bool *r_state)
+{
+	int ret;
+	u8 state;
+
+	if (!r_state)
+		return -EINVAL;
+
+	ret = ti_sci_get_device_state(handle, id, NULL, NULL, &state, NULL);
+	if (ret)
+		return ret;
+
+	*r_state = (state == MSG_DEVICE_SW_STATE_RETENTION);
+
+	return 0;
+}
+
+/**
+ * ti_sci_cmd_dev_is_stop() - Check if the device is requested to be stopped
+ * @handle:	Pointer to TISCI handle
+ * @id:		Device Identifier
+ * @r_state:	true if requested to be stopped
+ * @curr_state:	true if currently stopped.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_dev_is_stop(const struct ti_sci_handle *handle, u32 id,
+				  bool *r_state,  bool *curr_state)
+{
+	int ret;
+	u8 p_state, c_state;
+
+	if (!r_state && !curr_state)
+		return -EINVAL;
+
+	ret =
+	    ti_sci_get_device_state(handle, id, NULL, NULL, &p_state, &c_state);
+	if (ret)
+		return ret;
+
+	if (r_state)
+		*r_state = (p_state == MSG_DEVICE_SW_STATE_AUTO_OFF);
+	if (curr_state)
+		*curr_state = (c_state == MSG_DEVICE_HW_STATE_OFF);
+
+	return 0;
+}
+
+/**
+ * ti_sci_cmd_dev_is_on() - Check if the device is requested to be ON
+ * @handle:	Pointer to TISCI handle
+ * @id:		Device Identifier
+ * @r_state:	true if requested to be ON
+ * @curr_state:	true if currently ON and active
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_dev_is_on(const struct ti_sci_handle *handle, u32 id,
+				bool *r_state,  bool *curr_state)
+{
+	int ret;
+	u8 p_state, c_state;
+
+	if (!r_state && !curr_state)
+		return -EINVAL;
+
+	ret =
+	    ti_sci_get_device_state(handle, id, NULL, NULL, &p_state, &c_state);
+	if (ret)
+		return ret;
+
+	if (r_state)
+		*r_state = (p_state == MSG_DEVICE_SW_STATE_ON);
+	if (curr_state)
+		*curr_state = (c_state == MSG_DEVICE_HW_STATE_ON);
+
+	return 0;
+}
+
+/**
+ * ti_sci_cmd_dev_is_trans() - Check if the device is currently transitioning
+ * @handle:	Pointer to TISCI handle
+ * @id:		Device Identifier
+ * @curr_state:	true if currently transitioning.
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_dev_is_trans(const struct ti_sci_handle *handle, u32 id,
+				   bool *curr_state)
+{
+	int ret;
+	u8 state;
+
+	if (!curr_state)
+		return -EINVAL;
+
+	ret = ti_sci_get_device_state(handle, id, NULL, NULL, NULL, &state);
+	if (ret)
+		return ret;
+
+	*curr_state = (state == MSG_DEVICE_HW_STATE_TRANS);
+
+	return 0;
+}
+
+/**
+ * ti_sci_cmd_set_device_resets() - command to set resets for device managed
+ *				    by TISCI
+ * @handle:	Pointer to TISCI handle as retrieved by *ti_sci_get_handle
+ * @id:		Device Identifier
+ * @reset_state: Device specific reset bit field
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_set_device_resets(const struct ti_sci_handle *handle,
+					u32 id, u32 reset_state)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_msg_req_set_device_resets *req;
+	struct ti_sci_msg_hdr *resp;
+	struct ti_sci_xfer *xfer;
+	struct device *dev;
+	int ret = 0;
+
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+	if (!handle)
+		return -EINVAL;
+
+	info = handle_to_ti_sci_info(handle);
+	dev = info->dev;
+
+	xfer = ti_sci_get_one_xfer(info, TI_SCI_MSG_SET_DEVICE_RESETS,
+				   TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				   sizeof(*req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(dev, "Message alloc failed(%d)\n", ret);
+		return ret;
+	}
+	req = (struct ti_sci_msg_req_set_device_resets *)xfer->xfer_buf;
+	req->id = id;
+	req->resets = reset_state;
+
+	ret = ti_sci_do_xfer(info, xfer);
+	if (ret) {
+		dev_err(dev, "Mbox send fail %d\n", ret);
+		goto fail;
+	}
+
+	resp = (struct ti_sci_msg_hdr *)xfer->xfer_buf;
+
+	ret = ti_sci_is_response_ack(resp) ? 0 : -ENODEV;
+
+fail:
+	ti_sci_put_one_xfer(&info->minfo, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_cmd_get_device_resets() - Get reset state for device managed
+ *				    by TISCI
+ * @handle:		Pointer to TISCI handle
+ * @id:			Device Identifier
+ * @reset_state:	Pointer to reset state to populate
+ *
+ * Return: 0 if all went fine, else return appropriate error.
+ */
+static int ti_sci_cmd_get_device_resets(const struct ti_sci_handle *handle,
+					u32 id, u32 *reset_state)
+{
+	return ti_sci_get_device_state(handle, id, NULL, reset_state, NULL,
+				       NULL);
+}
+
+/*
+ * ti_sci_setup_ops() - Setup the operations structures
+ * @info:	pointer to TISCI pointer
+ */
+static void ti_sci_setup_ops(struct ti_sci_info *info)
+{
+	struct ti_sci_ops *ops = &info->handle.ops;
+	struct ti_sci_dev_ops *dops = &ops->dev_ops;
+
+	dops->get_device = ti_sci_cmd_get_device;
+	dops->idle_device = ti_sci_cmd_idle_device;
+	dops->put_device = ti_sci_cmd_put_device;
+
+	dops->is_valid = ti_sci_cmd_dev_is_valid;
+	dops->get_context_loss_count = ti_sci_cmd_dev_get_clcnt;
+	dops->is_idle = ti_sci_cmd_dev_is_idle;
+	dops->is_stop = ti_sci_cmd_dev_is_stop;
+	dops->is_on = ti_sci_cmd_dev_is_on;
+	dops->is_transitioning = ti_sci_cmd_dev_is_trans;
+	dops->set_device_resets = ti_sci_cmd_set_device_resets;
+	dops->get_device_resets = ti_sci_cmd_get_device_resets;
+}
+
+/**
  * ti_sci_get_handle() - Get the TI SCI handle for a device
  * @dev:	Pointer to device for which we want SCI handle
  *
@@ -727,6 +1158,8 @@ static int ti_sci_probe(struct platform_device *pdev)
 		goto out;
 	}
 
+	ti_sci_setup_ops(info);
+
 	dev_info(dev, "ABI: %d.%d (firmware rev 0x%04x '%s')\n",
 		 info->handle.version.abi_major, info->handle.version.abi_minor,
 		 info->handle.version.firmware_revision,