[PATCH] firmware: ti_sci: set IO Isolation only if the firmware is capable

[Thomas Richard (TI.com)]

Add the IO_ISOLATION firmware capability, and set IO Isolation during
suspend only if the firmware is capable.

Fixes: ec24643bdd62 ("firmware: ti_sci: Add system suspend and resume call")
Signed-off-by: Thomas Richard (TI.com) <thomas.richard at bootlin.com>
---
 drivers/firmware/ti_sci.c | 21 +++++++++++++--------
 drivers/firmware/ti_sci.h |  2 ++
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 49fd2ae01055d0f425062147422471f0fd49e4bd..8d96a3c12b36a908097805b44dc3343172fbbfec 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -3751,9 +3751,11 @@ static int __maybe_unused ti_sci_suspend_noirq(struct device *dev)
 	struct ti_sci_info *info = dev_get_drvdata(dev);
 	int ret = 0;
 
-	ret = ti_sci_cmd_set_io_isolation(&info->handle, TISCI_MSG_VALUE_IO_ENABLE);
-	if (ret)
-		return ret;
+	if (info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION) {
+		ret = ti_sci_cmd_set_io_isolation(&info->handle, TISCI_MSG_VALUE_IO_ENABLE);
+		if (ret)
+			return ret;
+	}
 
 	return 0;
 }
@@ -3767,9 +3769,11 @@ static int __maybe_unused ti_sci_resume_noirq(struct device *dev)
 	u8 pin;
 	u8 mode;
 
-	ret = ti_sci_cmd_set_io_isolation(&info->handle, TISCI_MSG_VALUE_IO_DISABLE);
-	if (ret)
-		return ret;
+	if (info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION) {
+		ret = ti_sci_cmd_set_io_isolation(&info->handle, TISCI_MSG_VALUE_IO_DISABLE);
+		if (ret)
+			return ret;
+	}
 
 	ret = ti_sci_msg_cmd_lpm_wake_reason(&info->handle, &source, &time, &pin, &mode);
 	/* Do not fail to resume on error as the wake reason is not critical */
@@ -3928,11 +3932,12 @@ static int ti_sci_probe(struct platform_device *pdev)
 	}
 
 	ti_sci_msg_cmd_query_fw_caps(&info->handle, &info->fw_caps);
-	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s\n",
+	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s\n",
 		info->fw_caps & MSG_FLAG_CAPS_GENERIC ? "Generic" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_PARTIAL_IO ? " Partial-IO" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED ? " DM-Managed" : "",
-		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : ""
+		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : "",
+		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : ""
 	);
 
 	ti_sci_setup_ops(info);
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index 701c416b2e78f8ef20ce6741a88ffa6fd4853b2d..7559cde17b6ccfeeb1bc357fce5c5767c3f75c54 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -149,6 +149,7 @@ struct ti_sci_msg_req_reboot {
  *		MSG_FLAG_CAPS_LPM_PARTIAL_IO: Partial IO in LPM
  *		MSG_FLAG_CAPS_LPM_DM_MANAGED: LPM can be managed by DM
  *		MSG_FLAG_CAPS_LPM_ABORT: Abort entry to LPM
+ *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
  *
  * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
  * providing currently available SOC/firmware capabilities. SoC that don't
@@ -160,6 +161,7 @@ struct ti_sci_msg_resp_query_fw_caps {
 #define MSG_FLAG_CAPS_LPM_PARTIAL_IO	TI_SCI_MSG_FLAG(4)
 #define MSG_FLAG_CAPS_LPM_DM_MANAGED	TI_SCI_MSG_FLAG(5)
 #define MSG_FLAG_CAPS_LPM_ABORT		TI_SCI_MSG_FLAG(9)
+#define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
 #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
 	u64 fw_caps;
 } __packed;

---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20251013-ti-sci-io-isolation-63a8bcd9d4e9

Best regards,
-- 
Thomas Richard (TI.com) <thomas.richard at bootlin.com>