Failure to register SGI for firmware event notification is non-fatal error
when feature is not supported by other modules such as Xen and TF-A. Add
_info level log message for such special case.

Also add XST_PM_INVALID_VERSION error code and map it to -EOPNOSUPP Linux
kernel error code. If feature is not supported or EEMI API version is
mismatch, firmware can return XST_PM_INVALID_VERSION = 4 or
XST_PM_NO_FEATURE = 19 error code.

Co-developed-by: Tanmay Shah <redacted>
Signed-off-by: Tanmay Shah <redacted>
Signed-off-by: Jay Buddhabhatti <redacted>
---
 drivers/firmware/xilinx/zynqmp.c        | 4 +++-
 drivers/soc/xilinx/xlnx_event_manager.c | 7 ++++++-
 include/linux/firmware/xlnx-zynqmp.h    | 1 +
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 00ea2508f692..de09d77cf1e4 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c

@@ -92,6 +92,8 @@ static int zynqmp_pm_ret_code(u32 ret_status)
 		return 0;
 	case XST_PM_NO_FEATURE:
 		return -ENOTSUPP;
+	case XST_PM_INVALID_VERSION:
+		return -EOPNOTSUPP;
 	case XST_PM_NO_ACCESS:
 		return -EACCES;
 	case XST_PM_ABORT_SUSPEND:

@@ -379,7 +381,7 @@ int zynqmp_pm_register_sgi(u32 sgi_num, u32 reset)
 
 	ret = zynqmp_pm_invoke_fn(TF_A_PM_REGISTER_SGI, sgi_num, reset, 0, 0,
 				  0, NULL);
-	if (!ret)
+	if (ret != -EOPNOTSUPP && !ret)
 		return ret;
 
 	/* try old implementation as fallback strategy if above fails */

diff --git a/drivers/soc/xilinx/xlnx_event_manager.c b/drivers/soc/xilinx/xlnx_event_manager.c
index 38cfc161a713..bfa5cf4a0cab 100644
--- a/drivers/soc/xilinx/xlnx_event_manager.c
+++ b/drivers/soc/xilinx/xlnx_event_manager.c

@@ -653,7 +653,12 @@ static int xlnx_event_manager_probe(struct platform_device *pdev)
 
 	ret = zynqmp_pm_register_sgi(sgi_num, 0);
 	if (ret) {
-		dev_err(&pdev->dev, "SGI %d Registration over TF-A failed with %d\n", sgi_num, ret);
+		if (ret == -EOPNOTSUPP)
+			dev_info(&pdev->dev, "PM firmware event notification not supported\n");