firmware: xilinx: Add TF_A_PM_REGISTER_SGI SMC call

SGI interrupt register and reset is performed by EEMI ioctl
IOCTL_REGISTER_SGI. However, this is not correct use of EEMI call.
SGI registration functionality does not qualify as energy management
activity and so shouldn't be mapped to EEMI call.

This new call will replace IOCTL_REGISTER_SGI and will be handled by TF-A
specific handler in TF-A. To maintain backward compatibility for a while
firmware driver will still use IOCTL_REGISTER_SGI as fallback strategy if
new call fails or is not supported by TF-A.

This new design also helps to make TF-A as pass through layer for EEMI
calls. So we don't have to maintain PM_IOCTL as EEMI API ID in TF-A.

Signed-off-by: Tanmay Shah <[e-mail]>
Acked-by: Michal Simek <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Michal Simek <[e-mail]>

drivers/firmware/xilinx/zynqmp.c

···
 /*
  * Xilinx Zynq MPSoC Firmware layer
  *
- *  Copyright (C) 2014-2021 Xilinx, Inc.
+ *  Copyright (C) 2014-2022 Xilinx, Inc.
  *
  *  Michal Simek <[e-mail]>
  *  Davorin Mista <[e-mail]>
···
 
 static u32 pm_api_version;
 static u32 pm_tz_version;
+
+int zynqmp_pm_register_sgi(u32 sgi_num, u32 reset)
+{
+	int ret;
+
+	ret = zynqmp_pm_invoke_fn(TF_A_PM_REGISTER_SGI, sgi_num, reset, 0, 0,
+				  NULL);
+	if (!ret)
+		return ret;
+
+	/* try old implementation as fallback strategy if above fails */
+	return zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_REGISTER_SGI, sgi_num,
+				   reset, NULL);
+}
 
 /**
  * zynqmp_pm_get_api_version() - Get version number of PMU PM firmware

drivers/soc/xilinx/xlnx_event_manager.c

···
 	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "soc/event:starting",
 			  xlnx_event_cpuhp_start, xlnx_event_cpuhp_down);
 
-	ret = zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_REGISTER_SGI, sgi_num,
-				  0, NULL);
+	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);
 		xlnx_event_cleanup_sgi(pdev);
···
 		kfree(eve_data);
 	}
 
-	ret = zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_REGISTER_SGI, 0, 1, NULL);
+	ret = zynqmp_pm_register_sgi(0, 1);
 	if (ret)
 		dev_err(&pdev->dev, "SGI unregistration over TF-A failed with %d\n", ret);
 

include/linux/firmware/xlnx-zynqmp.h

···
 #define PM_API_VERSION_2	2
 
 /* ATF only commands */
+#define TF_A_PM_REGISTER_SGI		0xa04
 #define PM_GET_TRUSTZONE_VERSION	0xa03
 #define PM_SET_SUSPEND_MODE		0xa02
 #define GET_CALLBACK_DATA		0xa01
···
 int zynqmp_pm_is_function_supported(const u32 api_id, const u32 id);
 int zynqmp_pm_set_feature_config(enum pm_feature_config_id id, u32 value);
 int zynqmp_pm_get_feature_config(enum pm_feature_config_id id, u32 *payload);
+int zynqmp_pm_register_sgi(u32 sgi_num, u32 reset);
 #else
 static inline int zynqmp_pm_get_api_version(u32 *version)
 {
···
 
 static inline int zynqmp_pm_get_feature_config(enum pm_feature_config_id id,
 					       u32 *payload)
+{
+	return -ENODEV;
+}
+
+static inline int zynqmp_pm_register_sgi(u32 sgi_num, u32 reset)
 {
 	return -ENODEV;
 }