[PATCH v5 03/21] firmware: ti_sci: add low power mode operations

["Richard Genoud (TI)" <richard.genoud@bootlin.com>]

From: Prasanth Babu Mantena <p-mantena@ti.com>

On TI-k3 platform, at resume, uboot SPL needs to do several tasks:
- restore TIFS minimal context from DDR
- send DDR save address to TIFS
- load TFA and its context in MSMC
- set TFA resume vector to its warm_entrypoint
- authenticate certificates and apply firewalls

All those operations are now done by TIFS with those messages:
ti_sci_cmd_min_context_restore
ti_sci_cmd_decrypt_tfa
ti_sci_cmd_core_resume
ti_sci_cmd_lpm_save_addr
ti_sci_cmd_proc_auth_apply_fwls

https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html
https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/security/PROC_BOOT.html

Signed-off-by: Prasanth Babu Mantena <p-mantena@ti.com>
Co-developed-by: Richard Genoud (TI) <richard.genoud@bootlin.com>
Signed-off-by: Richard Genoud (TI) <richard.genoud@bootlin.com>
---
 arch/arm/mach-k3/include/mach/security.h |   1 +
 arch/arm/mach-k3/security.c              |  62 ++++++++
 drivers/firmware/ti_sci.c                | 181 +++++++++++++++++++++++
 drivers/firmware/ti_sci.h                |  92 ++++++++++++
 include/linux/soc/ti/ti_sci_protocol.h   |   8 +
 5 files changed, 344 insertions(+)

diff --git a/arch/arm/mach-k3/include/mach/security.h b/arch/arm/mach-k3/include/mach/security.h
index 8502b57bd80a..fa90fed7c427 100644
--- a/arch/arm/mach-k3/include/mach/security.h
+++ b/arch/arm/mach-k3/include/mach/security.h
@@ -9,3 +9,4 @@
 #include <linux/types.h>
 
 void ti_secure_image_post_process(void **p_image, size_t *p_size);
+void ti_secure_image_auth_apply_fwls(void **p_image, size_t image_size);
diff --git a/arch/arm/mach-k3/security.c b/arch/arm/mach-k3/security.c
index c7017bba99ab..2df922a2fa27 100644
--- a/arch/arm/mach-k3/security.c
+++ b/arch/arm/mach-k3/security.c
@@ -133,3 +133,65 @@ void ti_secure_image_post_process(void **p_image, size_t *p_size)
 	      spl_boot_device() == BOOT_DEVICE_UART))
 		printf("Authentication passed\n");
 }
+
+void ti_secure_image_auth_apply_fwls(void **p_image, size_t image_size)
+{
+	struct ti_sci_handle *ti_sci = get_ti_sci_handle();
+	struct ti_sci_proc_ops *proc_ops = &ti_sci->ops.proc_ops;
+	u64 image_addr;
+	u32 backup_size;
+	int ret;
+
+	if (!image_size) {
+		debug("%s: Image size is null\n", __func__);
+		return;
+	}
+
+	if (get_device_type() == K3_DEVICE_TYPE_GP)
+		return;
+
+	if (get_device_type() != K3_DEVICE_TYPE_HS_SE &&
+	    !ti_secure_cert_detected(*p_image)) {
+		printf("Warning: Did not detect image signing certificate. "
+		       "Skipping authentication to prevent boot failure. "
+		       "This will fail on Security Enforcing(HS-SE) devices\n");
+		return;
+	}
+
+	/* Clean out image so it can be seen by system firmware */
+	image_addr = dma_map_single(*p_image, image_size, DMA_BIDIRECTIONAL);
+
+	debug("Authenticating image at address 0x%016llx\n", image_addr);
+	debug("Authenticating image of size %zu bytes\n", image_size);
+
+	/*
+	 * Authenticate image
+	 * The size argument is modified by proc_auth_apply_fwls and may be 0
+	 * when the authentication process has moved the image.
+	 * When this happens no further processing on the image is needed or
+	 * often even possible as it may have also been placed behind a firewall
+	 * when moved.
+	 * And moreover it expects a u32*. So, use the backup_size.
+	 */
+	backup_size = image_size;
+	ret = proc_ops->proc_auth_apply_fwls(ti_sci, &image_addr, &backup_size);
+	if (ret) {
+		printf("Authentication failed..but assume pass!\n");
+		hang();
+	}
+
+	/* Invalidate any stale lines over data written by system firmware */
+	dma_unmap_single(image_addr, image_size, DMA_BIDIRECTIONAL);
+
+	/*
+	 * Output notification of successful authentication to re-assure the
+	 * user that the secure code is being processed as expected. However
+	 * suppress any such log output in case of building for SPL and booting
+	 * via YMODEM. This is done to avoid disturbing the YMODEM serial
+	 * protocol transactions.
+	 */
+	if (!(IS_ENABLED(CONFIG_XPL_BUILD) &&
+	      IS_ENABLED(CONFIG_SPL_YMODEM_SUPPORT) &&
+	      spl_boot_device() == BOOT_DEVICE_UART))
+		printf("Certificate replay passed\n");
+}
diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index c015bd3cc245..050f4d61562a 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -2014,6 +2014,64 @@ static int ti_sci_cmd_set_proc_boot_ctrl(const struct ti_sci_handle *handle,
 	return ret;
 }
 
+/**
+ * ti_sci_cmd_proc_auth_apply_fwls() - Command to authenticate certificate and
+ *				       apply the firewalls present in it.
+ * @handle:	Pointer to TI SCI handle
+ * @image_addr:	Memory address at which payload image and certificate is
+ *		located in memory, this is updated if the image data is
+ *		moved during authentication.
+ * @image_size: This is updated with the final size of the image after
+ *		authentication.
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_proc_auth_apply_fwls(const struct ti_sci_handle *handle,
+					   u64 *image_addr, u32 *image_size)
+{
+	struct ti_sci_msg_req_proc_auth_boot_image req;
+	struct ti_sci_msg_resp_proc_auth_boot_image *resp;
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	int ret = 0;
+
+	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, TISCI_MSG_PROC_AUTH_APPLY_FWLS,
+				     TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				     (u32 *)&req, sizeof(req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(info->dev, "%s Error making the tisci command\n",
+			__func__);
+		return ret;
+	}
+	req.cert_addr_low = *image_addr & TISCI_ADDR_LOW_MASK;
+	req.cert_addr_high = (*image_addr & TISCI_ADDR_HIGH_MASK) >>
+				TISCI_ADDR_HIGH_SHIFT;
+
+	ret = ti_sci_do_xfer(info, xfer);
+	if (ret) {
+		dev_err(info->dev, "%s Error sending the tisci command\n",
+			__func__);
+		return ret;
+	}
+
+	resp = (struct ti_sci_msg_resp_proc_auth_boot_image *)xfer->tx_message.buf;
+
+	*image_addr = (resp->image_addr_low & TISCI_ADDR_LOW_MASK) |
+			(((u64)resp->image_addr_high <<
+			  TISCI_ADDR_HIGH_SHIFT) & TISCI_ADDR_HIGH_MASK);
+	*image_size = resp->image_size;
+
+	return ret;
+}
+
 /**
  * ti_sci_cmd_proc_auth_boot_image() - Command to authenticate and load the
  *			image and then set the processor configuration flags.
@@ -2745,6 +2803,125 @@ static int ti_sci_cmd_min_context_restore(const struct ti_sci_handle *handle, u6
 	return ret;
 }
 
+/**
+ * ti_sci_cmd_decrypt_tfa() - Request for decrypting TFA to specific address.
+ * @handle:    pointer to TI SCI handle
+ * @unencrypted_address: Address where the unencrypted TFA will be restored to.
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_decrypt_tfa(const struct ti_sci_handle *handle,
+				  u64 unencrypted_address)
+{
+	struct ti_sci_msg_decrypt_tfa_req req;
+	struct ti_sci_msg_decrypt_tfa_resp *resp;
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	int ret = 0;
+
+	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, TISCI_MSG_LPM_DECRYPT,
+				     TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				     (u32 *)&req, sizeof(req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		return ret;
+	}
+
+	req.unencrypted_address = unencrypted_address;
+
+	ret = ti_sci_do_xfer(info, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_cmd_core_resume() - Request for resuming TFA.
+ *
+ * The TIFS will launch the TFA from the entrypoint saved via the ENTER_SLEEP
+ * message.
+ *
+ * @handle:    pointer to TI SCI handle
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_core_resume(const struct ti_sci_handle *handle)
+{
+	struct ti_sci_msg_core_resume_req req;
+	struct ti_sci_msg_core_resume_resp *resp;
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	int ret = 0;
+
+	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, TISCI_MSG_CORE_RESUME,
+				     TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				     (u32 *)&req, sizeof(req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		return ret;
+	}
+
+	ret = ti_sci_do_xfer(info, xfer);
+
+	return ret;
+}
+
+/**
+ * ti_sci_cmd_lpm_save_addr() - Message to inform TIFS about the context save address.
+ *
+ * By restoring its context, TIFS will restore its firewall.
+ *
+ * @handle:    pointer to TI SCI handle
+ * @context_addr:  address where the context will be store to and restored from
+ * @size:	   Size of the context save region
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_lpm_save_addr(const struct ti_sci_handle *handle,
+				    u64 context_addr, u32 size)
+{
+	struct tisci_msg_lpm_save_ctx_addr_req req;
+	struct tisci_msg_lpm_save_ctx_addr_resp *resp;
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	int ret = 0;
+
+	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, TISCI_MSG_LPM_SAVE_ADDR,
+				     TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				     (u32 *)&req, sizeof(req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		return ret;
+	}
+
+	req.ctx_addr = context_addr;
+	req.size = size;
+
+	ret = ti_sci_do_xfer(info, xfer);
+
+	return ret;
+}
+
 /*
  * ti_sci_setup_ops() - Setup the operations structures
  * @info:	pointer to TISCI pointer
@@ -2813,6 +2990,7 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	pops->set_proc_boot_cfg = ti_sci_cmd_set_proc_boot_cfg;
 	pops->set_proc_boot_ctrl = ti_sci_cmd_set_proc_boot_ctrl;
 	pops->proc_auth_boot_image = ti_sci_cmd_proc_auth_boot_image;
+	pops->proc_auth_apply_fwls = ti_sci_cmd_proc_auth_apply_fwls;
 	pops->get_proc_boot_status = ti_sci_cmd_get_proc_boot_status;
 	pops->proc_shutdown_no_wait = ti_sci_cmd_proc_shutdown_no_wait;
 
@@ -2833,6 +3011,9 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	fw_ops->query_dm_cap = ti_sci_cmd_query_dm_cap;
 
 	lpm_ops->min_context_restore = ti_sci_cmd_min_context_restore;
+	lpm_ops->decrypt_tfa = ti_sci_cmd_decrypt_tfa;
+	lpm_ops->core_resume = ti_sci_cmd_core_resume;
+	lpm_ops->lpm_save_addr = ti_sci_cmd_lpm_save_addr;
 }
 
 /**
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index 68908c6c8c46..d6ae08144d46 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -57,6 +57,7 @@
 #define TISCI_MSG_PROC_AUTH_BOOT_IMAGE	0xc120
 #define TISCI_MSG_GET_PROC_BOOT_STATUS	0xc400
 #define TISCI_MSG_WAIT_PROC_BOOT_STATUS	0xc401
+#define TISCI_MSG_PROC_AUTH_APPLY_FWLS	0xc402
 
 /* Resource Management Requests */
 #define TI_SCI_MSG_GET_RESOURCE_RANGE	0x1500
@@ -85,6 +86,24 @@
 #define TISCI_MSG_FWL_GET		0x9001
 #define TISCI_MSG_FWL_CHANGE_OWNER	0x9002
 
+/* LPM requests */
+#define TISCI_MSG_SYNC_RESUME			(0x0302U)
+#define TISCI_MSG_CONTINUE_RESUME		(0x0303U)
+#define TISCI_MSG_CORE_RESUME			(0x0304U)
+#define TISCI_MSG_ABORT_ENTER_SLEEP		(0x0305U)
+#define TISCI_MSG_LPM_WAKE_REASON		(0x0306U)
+#define TISCI_MSG_SET_IO_ISOLATION		(0x0307U)
+#define TISCI_MSG_MIN_CONTEXT_RESTORE		(0x0308U)
+#define TISCI_MSG_LPM_SET_DEVICE_CONSTRAINT	(0x0309U)
+#define TISCI_MSG_LPM_SET_LATENCY_CONSTRAINT	(0x030AU)
+#define TISCI_MSG_LPM_GET_DEVICE_CONSTRAINT	(0x030BU)
+#define TISCI_MSG_LPM_GET_LATENCY_CONSTRAINT	(0x030CU)
+#define TISCI_MSG_LPM_GET_NEXT_SYS_MODE		(0x030DU)
+#define TISCI_MSG_LPM_GET_NEXT_HOST_STATE	(0x030EU)
+#define TISCI_MSG_LPM_ENCRYPT			(0x030FU)
+#define TISCI_MSG_LPM_DECRYPT			(0x0310U)
+#define TISCI_MSG_LPM_SAVE_ADDR			(0x0313U)
+
 /**
  * struct ti_sci_msg_hdr - Generic Message Header for All messages and responses
  * @type:	Type of messages: One of TI_SCI_MSG* values
@@ -1588,4 +1607,77 @@ struct ti_sci_msg_min_restore_context_req {
 	u32			ctx_hi;
 } __packed;
 
+/*
+ * struct ti_sci_msg_core_resume_req - Request for TISCI_MSG_CORE_RESUME.
+ *
+ * @hdr:			Generic Header
+ *
+ * This message is to be sent to start the TFA on the main core.
+ * The TIFS will launch the TFA from the entrypoint saved via the ENTER_SLEEP
+ * message.
+ */
+struct ti_sci_msg_core_resume_req {
+	struct ti_sci_msg_hdr	hdr;
+} __packed;
+
+/**
+ * struct ti_sci_msg_core_resume_resp - Response for TISCI_MSG_CORE_RESUME.
+ *
+ * @hdr:			Generic Header
+ */
+struct ti_sci_msg_core_resume_resp {
+	struct ti_sci_msg_hdr	hdr;
+} __packed;
+
+/**
+ * struct ti_sci_msg_decrypt_tfa_req - Request for TISCI_MSG_LPM_DECRYPT.
+ *
+ * @hdr:			Generic Header
+ * @unencrypted_address:	Address where the TFA should be decrypted
+ * @encrypted_address:		Address where the TFA lies encrypted
+ *
+ * This message is to be sent when the system is resuming from suspend, in order
+ * to restore the TFA.
+ * The TIFS will decrypt the TFA at specified location and restore it in SRAM.
+ */
+struct ti_sci_msg_decrypt_tfa_req {
+	struct ti_sci_msg_hdr	hdr;
+	u64			unencrypted_address;
+} __packed;
+
+/**
+ * struct ti_sci_msg_decrypt_tfa_resp - Response for TISCI_MSG_LPM_DECRYPT.
+ *
+ * @hdr:			Generic Header
+ */
+struct ti_sci_msg_decrypt_tfa_resp {
+	struct ti_sci_msg_hdr	hdr;
+} __packed;
+
+/**
+ * struct tisci_msg_lpm_save_ctx_addr_req - Request for TISCI_MSG_LPM_SAVE_ADDR.
+ *
+ * @hdr:			Generic Header
+ * @ctx_addr:	Address where the LPM data is to be saved
+ * @size:		Size of the context save memory region
+ *
+ * This message is sent to TIFS to inform it about the address where it
+ * will save the context to in case of system suspend and where to get the
+ * context back from when resuming the system
+ */
+struct tisci_msg_lpm_save_ctx_addr_req {
+	struct ti_sci_msg_hdr	hdr;
+	u64			ctx_addr;
+	u32			size;
+} __packed;
+
+/**
+ * struct tisci_msg_lpm_save_ctx_addr_resp - Response for TISCI_MSG_SAVE_ADDR.
+ *
+ * @hdr:			Generic Header
+ */
+struct tisci_msg_lpm_save_ctx_addr_resp {
+	struct ti_sci_msg_hdr	hdr;
+} __packed;
+
 #endif /* __TI_SCI_H */
diff --git a/include/linux/soc/ti/ti_sci_protocol.h b/include/linux/soc/ti/ti_sci_protocol.h
index 6b1dd801f5f8..1d0a6340e1ee 100644
--- a/include/linux/soc/ti/ti_sci_protocol.h
+++ b/include/linux/soc/ti/ti_sci_protocol.h
@@ -336,6 +336,8 @@ struct ti_sci_proc_ops {
 				    u32 *sts_flags);
 	int (*proc_shutdown_no_wait)(const struct ti_sci_handle *handle,
 				     u8 pid);
+	int (*proc_auth_apply_fwls)(const struct ti_sci_handle *handle,
+				    u64 *image_addr, u32 *image_size);
 };
 
 #define TI_SCI_RING_MODE_RING			(0)
@@ -635,9 +637,15 @@ struct ti_sci_fwl_ops {
 /**
  * struct ti_sci_lpm_ops - Low Power Mode operations
  * @min_context_restore: Request restoring context from DDR.
+ * @decrypt_tfa: Request for decrypting TFA at specific address.
+ * @core_resume: Request for resuming TFA once decrypted.
+ * @lpm_save_addr: Send DDR Save address to TIFS
  */
 struct ti_sci_lpm_ops {
 	int (*min_context_restore)(const struct ti_sci_handle *handle, u64 ctx_addr);
+	int (*decrypt_tfa)(const struct ti_sci_handle *handle,	u64 unencrypted_address);
+	int (*core_resume)(const struct ti_sci_handle *handle);
+	int (*lpm_save_addr)(const struct ti_sci_handle *handle, u64 context_addr, u32 size);
 };
 
 /**