feat(ti): add enter sleep method

This TISCI API must be used to trigger entry into system suspend, and
this is done through the use of TI_SCI_MSG_ENTER_SLEEP. Introduce a
method to send this message.

Change-Id: Id7af5fb2a34623ad69e76764f389ff4d8d259fba
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>

3 files changed, 95 insertions, 3 deletions

diff --git a/plat/ti/k3/common/drivers/ti_sci/ti_sci.c b/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
index 2c3313c43..2cbfa3d6e 100644
--- a/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
+++ b/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
@@ -2,7 +2,7 @@
  * Texas Instruments System Control Interface Driver
  *   Based on Linux and U-Boot implementation
  *
- * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Copyright (C) 2018-2022 Texas Instruments Incorporated - https://www.ti.com/
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -1664,6 +1664,57 @@ int ti_sci_proc_wait_boot_status_no_wait(uint8_t proc_id,
 }
 
 /**
+ * ti_sci_enter_sleep - Command to initiate system transition into suspend.
+ *
+ * @proc_id: Processor ID.
+ * @mode: Low power mode to enter.
+ * @core_resume_addr: Address that core should be
+ *		      resumed from after low power transition.
+ *
+ * Return: 0 if all goes well, else appropriate error message
+ */
+int ti_sci_enter_sleep(uint8_t proc_id,
+		       uint8_t mode,
+		       uint64_t core_resume_addr)
+{
+	struct ti_sci_msg_req_enter_sleep req;
+	struct ti_sci_msg_hdr *hdr;
+	struct k3_sec_proxy_msg tx_message;
+	int ret;
+
+	/* Ensure we have sane transfer size */
+	if (sizeof(req) > TI_SCI_MAX_MESSAGE_SIZE) {
+		return -ERANGE;
+	}
+
+	hdr = (struct ti_sci_msg_hdr *)&req;
+	hdr->seq = ++message_sequence;
+	hdr->type = TI_SCI_MSG_ENTER_SLEEP;
+	hdr->host = TI_SCI_HOST_ID;
+	/* Setup with NORESPONSE flag to keep response queue clean */
+	hdr->flags = TI_SCI_FLAG_REQ_GENERIC_NORESPONSE;
+
+	req.processor_id = proc_id;
+	req.mode = mode;
+	req.core_resume_lo = core_resume_addr & TISCI_ADDR_LOW_MASK;
+	req.core_resume_hi = (core_resume_addr & TISCI_ADDR_HIGH_MASK) >>
+			     TISCI_ADDR_HIGH_SHIFT;
+
+	tx_message.buf = (uint8_t *)&req;
+	tx_message.len = sizeof(req);
+
+	/* Send message */
+	ret = k3_sec_proxy_send(SP_HIGH_PRIORITY, &tx_message);
+	if (ret != 0) {
+		ERROR("Message sending failed (%d)\n", ret);
+		return ret;
+	}
+
+	/* Return without waiting for response */
+	return 0;
+}
+
+/**
  * ti_sci_init() - Basic initialization
  *
  * Return: 0 if all goes well, else appropriate error message
diff --git a/plat/ti/k3/common/drivers/ti_sci/ti_sci.h b/plat/ti/k3/common/drivers/ti_sci/ti_sci.h
index c7b09b30d..06944a74b 100644
--- a/plat/ti/k3/common/drivers/ti_sci/ti_sci.h
+++ b/plat/ti/k3/common/drivers/ti_sci/ti_sci.h
@@ -2,7 +2,7 @@
  * Texas Instruments System Control Interface API
  *   Based on Linux and U-Boot implementation
  *
- * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Copyright (C) 2018-2022 Texas Instruments Incorporated - https://www.ti.com/
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -207,6 +207,22 @@ int ti_sci_proc_wait_boot_status_no_wait(uint8_t proc_id,
 					 uint32_t status_flags_1_clr_any_wait);
 
 /**
+ * System Low Power Operations
+ *
+ * - ti_sci_enter_sleep - Command to initiate system transition into suspend.
+ *		@proc_id: Processor ID.
+ *		@mode: Low power mode to enter.
+ *		@core_resume_addr: Address that core should be resumed from
+ *				   after low power transition.
+ *
+ * NOTE: for all these functions, the following are generic in nature:
+ * Returns 0 for successful request, else returns corresponding error message.
+ */
+int ti_sci_enter_sleep(uint8_t proc_id,
+		       uint8_t mode,
+		       uint64_t core_resume_addr);
+
+/**
  * ti_sci_init() - Basic initialization
  *
  * Return: 0 if all goes good, else appropriate error message.
diff --git a/plat/ti/k3/common/drivers/ti_sci/ti_sci_protocol.h b/plat/ti/k3/common/drivers/ti_sci/ti_sci_protocol.h
index 310bf459d..d220612ee 100644
--- a/plat/ti/k3/common/drivers/ti_sci/ti_sci_protocol.h
+++ b/plat/ti/k3/common/drivers/ti_sci/ti_sci_protocol.h
@@ -5,7 +5,7 @@
  * The system works in a message response protocol
  * See: http://processors.wiki.ti.com/index.php/TISCI for details
  *
- * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Copyright (C) 2018-2022 Texas Instruments Incorporated - https://www.ti.com/
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -28,6 +28,9 @@
 #define TI_SCI_MSG_GET_DEVICE_STATE	0x0201
 #define TI_SCI_MSG_SET_DEVICE_RESETS	0x0202
 
+/* Low Power Mode Requests */
+#define TI_SCI_MSG_ENTER_SLEEP		0x0301
+
 /* Clock requests */
 #define TI_SCI_MSG_SET_CLOCK_STATE	0x0100
 #define TI_SCI_MSG_GET_CLOCK_STATE	0x0101
@@ -706,4 +709,26 @@ struct ti_sci_msg_req_wait_proc_boot_status {
 	uint32_t status_flags_1_clr_any_wait;
 } __packed;
 
+/**
+ * struct ti_sci_msg_req_enter_sleep - Request for TI_SCI_MSG_ENTER_SLEEP.
+ *
+ * @hdr		    Generic Header
+ * @mode	    Low power mode to enter.
+ * @proc_id	    Processor id to be restored.
+ * @core_resume_lo  Low 32-bits of physical pointer to address for core
+ *		    to begin execution upon resume.
+ * @core_resume_hi  High 32-bits of physical pointer to address for core
+ *		    to begin execution upon resume.
+ *
+ * This message is to be sent after TI_SCI_MSG_PREPARE_SLEEP is sent from OS
+ * and is what actually triggers entry into the specified low power mode.
+ */
+struct ti_sci_msg_req_enter_sleep {
+	struct ti_sci_msg_hdr hdr;
+	uint8_t mode;
+	uint8_t processor_id;
+	uint32_t core_resume_lo;
+	uint32_t core_resume_hi;
+} __packed;
+
 #endif /* TI_SCI_PROTOCOL_H */