[PATCH v9 3/4] firmware: ti_sci: Introduce Power Management Ops

[Markus Schneider-Pargmann <msp@baylibre.com>]

From: Dave Gerlach <d-gerlach@ti.com>

Introduce power management ops supported by the TISCI
Low Power Mode API [1].

1) TISCI_MSG_LPM_WAKE_REASON
Get which wake up source woke the SoC from Low Power Mode.
The wake up source IDs will be common for all K3 platforms.

2) TISCI_MSG_LPM_SET_DEVICE_CONSTRAINT
Set LPM constraint on behalf of a device. By setting a constraint, the
device ensures that it will not be powered off or reset in the selected
mode.

3) TISCI_MSG_LPM_SET_LATENCY_CONSTRAINT
Set LPM resume latency constraint. By setting a constraint, the host
ensures that the resume time from selected mode will be less than the
constraint value.

[1] https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
[g-vlaev@ti.com: LPM_WAKE_REASON and IO_ISOLATION support]
Signed-off-by: Georgi Vlaev <g-vlaev@ti.com>
[a-kaur@ti.com: SET_DEVICE_CONSTRAINT support]
Signed-off-by: Akashdeep Kaur <a-kaur@ti.com>
[vibhore@ti.com: SET_LATENCY_CONSTRAINT support]
Signed-off-by: Vibhore Vardhan <vibhore@ti.com>
Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
---
 drivers/firmware/ti_sci.c              | 175 +++++++++++++++++++++++++
 drivers/firmware/ti_sci.h              |  70 ++++++++++
 include/linux/soc/ti/ti_sci_protocol.h |  42 ++++++
 3 files changed, 287 insertions(+)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 808149dcc635..5cbeca5df313 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -1822,6 +1822,173 @@ static int ti_sci_cmd_set_io_isolation(const struct ti_sci_handle *handle,
 	return ret;
 }
 
+/**
+ * ti_sci_msg_cmd_lpm_wake_reason() - Get the wakeup source from LPM
+ * @handle:		Pointer to TI SCI handle
+ * @source:		The wakeup source that woke the SoC from LPM
+ * @timestamp:		Timestamp of the wakeup event
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_msg_cmd_lpm_wake_reason(const struct ti_sci_handle *handle,
+					  u32 *source, u64 *timestamp)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	struct ti_sci_msg_resp_lpm_wake_reason *resp;
+	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_LPM_WAKE_REASON,
+				   TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				   sizeof(struct ti_sci_msg_hdr),
+				   sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(dev, "Message alloc failed(%d)\n", ret);
+		return ret;
+	}
+
+	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_lpm_wake_reason *)xfer->xfer_buf;
+
+	if (!ti_sci_is_response_ack(resp)) {
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	if (source)
+		*source = resp->wake_source;
+	if (timestamp)
+		*timestamp = resp->wake_timestamp;
+
+fail:
+	ti_sci_put_one_xfer(&info->minfo, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_cmd_set_device_constraint() - Set LPM constraint on behalf of a device
+ * @handle:	pointer to TI SCI handle
+ * @id:	Device identifier
+ * @state:	The desired state of device constraint: set or clear
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_set_device_constraint(const struct ti_sci_handle *handle,
+					    u32 id, u8 state)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_msg_req_lpm_set_device_constraint *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_LPM_SET_DEVICE_CONSTRAINT,
+				   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_lpm_set_device_constraint *)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_cmd_set_latency_constraint() - Set LPM resume latency constraint
+ * @handle:	pointer to TI SCI handle
+ * @latency:	maximum acceptable latency (in ms) to wake up from LPM
+ * @state:	The desired state of latency constraint: set or clear
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_set_latency_constraint(const struct ti_sci_handle *handle,
+					     u16 latency, u8 state)
+{
+	struct ti_sci_info *info;
+	struct ti_sci_msg_req_lpm_set_latency_constraint *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_LPM_SET_LATENCY_CONSTRAINT,
+				   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_lpm_set_latency_constraint *)xfer->xfer_buf;
+	req->latency = latency;
+	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;
+}
+
 static int ti_sci_cmd_core_reboot(const struct ti_sci_handle *handle)
 {
 	struct ti_sci_info *info;
@@ -2964,6 +3131,7 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	struct ti_sci_core_ops *core_ops = &ops->core_ops;
 	struct ti_sci_dev_ops *dops = &ops->dev_ops;
 	struct ti_sci_clk_ops *cops = &ops->clk_ops;
+	struct ti_sci_pm_ops *pmops = &ops->pm_ops;
 	struct ti_sci_rm_core_ops *rm_core_ops = &ops->rm_core_ops;
 	struct ti_sci_rm_irq_ops *iops = &ops->rm_irq_ops;
 	struct ti_sci_rm_ringacc_ops *rops = &ops->rm_ring_ops;
@@ -3003,6 +3171,13 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	cops->set_freq = ti_sci_cmd_clk_set_freq;
 	cops->get_freq = ti_sci_cmd_clk_get_freq;
 
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED) {
+		pr_debug("detected DM managed LPM in fw_caps\n");
+		pmops->lpm_wake_reason = ti_sci_msg_cmd_lpm_wake_reason;
+		pmops->set_device_constraint = ti_sci_cmd_set_device_constraint;
+		pmops->set_latency_constraint = ti_sci_cmd_set_latency_constraint;
+	}
+
 	rm_core_ops->get_range = ti_sci_cmd_get_resource_range;
 	rm_core_ops->get_range_from_shost =
 				ti_sci_cmd_get_resource_range_from_shost;
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index 8efe4d0e61fb..9dd40b6711d4 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -38,7 +38,10 @@
 
 /* Low Power Mode Requests */
 #define TI_SCI_MSG_PREPARE_SLEEP	0x0300
+#define TI_SCI_MSG_LPM_WAKE_REASON	0x0306
 #define TI_SCI_MSG_SET_IO_ISOLATION	0x0307
+#define TI_SCI_MSG_LPM_SET_DEVICE_CONSTRAINT	0x0309
+#define TI_SCI_MSG_LPM_SET_LATENCY_CONSTRAINT	0x030A
 
 /* Resource Management Requests */
 #define TI_SCI_MSG_GET_RESOURCE_RANGE	0x1500
@@ -610,6 +613,73 @@ struct ti_sci_msg_req_set_io_isolation {
 	u8 state;
 } __packed;
 
+/**
+ * struct ti_sci_msg_resp_lpm_wake_reason - Response for TI_SCI_MSG_LPM_WAKE_REASON.
+ *
+ * @hdr:		Generic header.
+ * @wake_source:	The wake up source that woke soc from LPM.
+ * @wake_timestamp:	Timestamp at which soc woke.
+ *
+ * Response to a generic message with message type TI_SCI_MSG_LPM_WAKE_REASON,
+ * used to query the wake up source from low power mode.
+ */
+struct ti_sci_msg_resp_lpm_wake_reason {
+	struct ti_sci_msg_hdr hdr;
+	u32 wake_source;
+	u64 wake_timestamp;
+} __packed;
+
+/**
+ * struct ti_sci_msg_req_lpm_set_device_constraint - Request for
+ * TISCI_MSG_LPM_SET_DEVICE_CONSTRAINT.
+ *
+ * @hdr:	TISCI header to provide ACK/NAK flags to the host.
+ * @id:	Device ID of device whose constraint has to be modified.
+ * @state:	The desired state of device constraint: set or clear.
+ * @rsvd:	Reserved for future use.
+ *
+ * This message is used by host to set constraint on the device. This can be
+ * sent anytime after boot before prepare sleep message. Any device can set a
+ * constraint on the low power mode that the SoC can enter. It allows
+ * configurable information to be easily shared from the application, as this
+ * is a non-secure message and therefore can be sent by anyone. By setting a
+ * constraint, the device ensures that it will not be powered off or reset in
+ * the selected mode. Note: Access Restriction: Exclusivity flag of Device will
+ * be honored. If some other host already has constraint on this device ID,
+ * NACK will be returned.
+ */
+struct ti_sci_msg_req_lpm_set_device_constraint {
+	struct ti_sci_msg_hdr hdr;
+	u32 id;
+	u8 state;
+	u32 rsvd[2];
+} __packed;
+
+/**
+ * struct ti_sci_msg_req_lpm_set_latency_constraint - Request for
+ * TISCI_MSG_LPM_SET_LATENCY_CONSTRAINT.
+ *
+ * @hdr:	TISCI header to provide ACK/NAK flags to the host.
+ * @wkup_latency:	The maximum acceptable latency to wake up from low power mode
+ *			in milliseconds. The deeper the state, the higher the latency.
+ * @state:	The desired state of wakeup latency constraint: set or clear.
+ * @rsvd:	Reserved for future use.
+ *
+ * This message is used by host to set wakeup latency from low power mode. This can
+ * be sent anytime after boot before prepare sleep message, and can be sent after
+ * current low power mode is exited. Any device can set a constraint on the low power
+ * mode that the SoC can enter. It allows configurable information to be easily shared
+ * from the application, as this is a non-secure message and therefore can be sent by
+ * anyone. By setting a wakeup latency constraint, the host ensures that the resume time
+ * from selected low power mode will be less than the constraint value.
+ */
+struct ti_sci_msg_req_lpm_set_latency_constraint {
+	struct ti_sci_msg_hdr hdr;
+	u16 latency;
+	u8 state;
+	u32 rsvd;
+} __packed;
+
 #define TI_SCI_IRQ_SECONDARY_HOST_INVALID	0xff
 
 /**
diff --git a/include/linux/soc/ti/ti_sci_protocol.h b/include/linux/soc/ti/ti_sci_protocol.h
index 1f1871e23f76..e781381e2f7c 100644
--- a/include/linux/soc/ti/ti_sci_protocol.h
+++ b/include/linux/soc/ti/ti_sci_protocol.h
@@ -199,6 +199,47 @@ struct ti_sci_clk_ops {
 #define TISCI_MSG_VALUE_IO_ENABLE			1
 #define TISCI_MSG_VALUE_IO_DISABLE			0
 
+/* TISCI LPM wake up sources */
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_I2C0	0x00
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_UART0	0x10
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_MCU_GPIO0	0x20
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_ICEMELTER0	0x30
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_TIMER0	0x40
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_TIMER1	0x41
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_WKUP_RTC0	0x50
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_RESET		0x60
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_USB0		0x70
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_USB1		0x71
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_MAIN_IO		0x80
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_MCU_IO		0x81
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_CAN_IO		0x82
+#define TISCI_MSG_VALUE_LPM_WAKE_SOURCE_INVALID		0xFF
+
+/* TISCI LPM constraint state values */
+#define TISCI_MSG_CONSTRAINT_SET			1
+#define TISCI_MSG_CONSTRAINT_CLR			0
+
+/**
+ * struct ti_sci_pm_ops - Low Power Mode (LPM) control operations
+ * @lpm_wake_reason: Get the wake up source that woke the SoC from LPM
+ *		- source: The wake up source that woke soc from LPM.
+ *		- timestamp: Timestamp at which soc woke.
+ * @set_device_constraint: Set LPM constraint on behalf of a device
+ *		- id: Device Identifier
+ *		- state: The desired state of device constraint: set or clear.
+ * @set_latency_constraint: Set LPM resume latency constraint
+ *		- latency: maximum acceptable latency to wake up from low power mode
+ *		- state: The desired state of latency constraint: set or clear.
+ */
+struct ti_sci_pm_ops {
+	int (*lpm_wake_reason)(const struct ti_sci_handle *handle,
+			       u32 *source, u64 *timestamp);
+	int (*set_device_constraint)(const struct ti_sci_handle *handle,
+				     u32 id, u8 state);
+	int (*set_latency_constraint)(const struct ti_sci_handle *handle,
+				      u16 latency, u8 state);
+};
+
 /**
  * struct ti_sci_resource_desc - Description of TI SCI resource instance range.
  * @start:	Start index of the first resource range.
@@ -543,6 +584,7 @@ struct ti_sci_ops {
 	struct ti_sci_core_ops core_ops;
 	struct ti_sci_dev_ops dev_ops;
 	struct ti_sci_clk_ops clk_ops;
+	struct ti_sci_pm_ops pm_ops;
 	struct ti_sci_rm_core_ops rm_core_ops;
 	struct ti_sci_rm_irq_ops rm_irq_ops;
 	struct ti_sci_rm_ringacc_ops rm_ring_ops;
-- 
2.45.2