[PATCH v10 5/6] tools/xl/libxl: wire up SCMI SMC multi-agent configuration

[Oleksii Moisieiev <Oleksii_Moisieiev@xxxxxxxx>]

Plumb the SCMI SMC multi-agent type through the toolstack:

- Extend libxl_arm_sci_type enumeration with scmi_smc_multiagent (value 2)
- Add agent_id field to libxl_arm_sci structure for per-domain agent assignment
- Update libxl_arm.c to translate libxl config to 
XEN_DOMCTL_CONFIG_ARM_SCI_SCMI_SMC_MA
  and pass agent_id to the hypervisor via xen_domctl_createdomain
- Add xl.cfg parsing for arm_sci="type=scmi_smc_multiagent,agent_id=N"
- Document the new xl.cfg options in xl.cfg.5.pod.in

This completes the userspace side of multi-agent SCMI, allowing xl create
and dom0less configurations to assign unique agent_id values to domains.

Signed-off-by: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
---

Changes in v10:
- Split hypervisor and toolstack changes into separate commits

 docs/man/xl.cfg.5.pod.in         | 14 ++++++++++++++
 tools/libs/light/libxl_arm.c     |  4 ++++
 tools/libs/light/libxl_types.idl |  4 +++-
 tools/xl/xl_parse.c              | 12 ++++++++++++
 4 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
index 27c455210b..e7f8af6156 100644
--- a/docs/man/xl.cfg.5.pod.in
+++ b/docs/man/xl.cfg.5.pod.in
@@ -3156,8 +3156,22 @@ single SCMI OSPM agent support.
 Should be used together with B<scmi-smc-passthrough> Xen command line
 option.
 
+=item B<scmi_smc_multiagent>
+
+Enables ARM SCMI SMC multi-agent support for the guest by enabling SCMI over
+SMC calls forwarding from domain to the EL3 firmware (like Trusted Firmware-A)
+with a multi SCMI OSPM agent support. The SCMI B<agent_id> should be
+specified for the guest.
+
 =back
 
+=item B<agent_id=NUMBER>
+
+Specifies a non-zero ARM SCI agent id for the guest. This option is mandatory
+if the SCMI SMC support is enabled for the guest. The agent ids of domains
+existing on a single host must be unique and in the range [0..254]. UINT8_MAX
+(255) is treated as invalid.
+
 =back
 
 =back
diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
index e4407d6e3f..be0e6263ae 100644
--- a/tools/libs/light/libxl_arm.c
+++ b/tools/libs/light/libxl_arm.c
@@ -240,6 +240,10 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
     case LIBXL_ARM_SCI_TYPE_SCMI_SMC:
         config->arch.arm_sci_type = XEN_DOMCTL_CONFIG_ARM_SCI_SCMI_SMC;
         break;
+    case LIBXL_ARM_SCI_TYPE_SCMI_SMC_MULTIAGENT:
+        config->arch.arm_sci_type = XEN_DOMCTL_CONFIG_ARM_SCI_SCMI_SMC_MA;
+        config->arch.arm_sci_agent_id = 
d_config->b_info.arch_arm.arm_sci.agent_id;
+        break;
     default:
         LOG(ERROR, "Unknown ARM_SCI type %d",
             d_config->b_info.arch_arm.arm_sci.type);
diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
index 4a958f69f4..9bfbf09145 100644
--- a/tools/libs/light/libxl_types.idl
+++ b/tools/libs/light/libxl_types.idl
@@ -554,11 +554,13 @@ libxl_sve_type = Enumeration("sve_type", [
 
 libxl_arm_sci_type = Enumeration("arm_sci_type", [
     (0, "none"),
-    (1, "scmi_smc")
+    (1, "scmi_smc"),
+    (2, "scmi_smc_multiagent")
     ], init_val = "LIBXL_ARM_SCI_TYPE_NONE")
 
 libxl_arm_sci = Struct("arm_sci", [
     ("type", libxl_arm_sci_type),
+    ("agent_id", uint8)
     ])
 
 libxl_rdm_reserve = Struct("rdm_reserve", [
diff --git a/tools/xl/xl_parse.c b/tools/xl/xl_parse.c
index 1cc41f1bff..2f1b475022 100644
--- a/tools/xl/xl_parse.c
+++ b/tools/xl/xl_parse.c
@@ -1306,6 +1306,18 @@ static int parse_arm_sci_config(XLU_Config *cfg, 
libxl_arm_sci *arm_sci,
             }
         }
 
+        if (MATCH_OPTION("agent_id", ptr, oparg)) {
+            unsigned long val = parse_ulong(oparg);
+
+            if ( val >= UINT8_MAX ) {
+                fprintf(stderr, "An invalid ARM_SCI agent_id specified (%lu). 
Valid range [0..254]\n",
+                        val);
+                ret = ERROR_INVAL;
+                goto out;
+            }
+            arm_sci->agent_id = val;
+        }
+
         ptr = strtok(NULL, ",");
     }
 
-- 
2.34.1