[PATCH v3 2/3] x86/platform: introduce XENPF_get_ucode_version

[Sergey Dyasli <sergey.dyasli@xxxxxxxxxx>]

Currently it's impossible to get CPU's microcode revision after late
loading without looking into Xen logs which is not always convenient.

Add a new platform op in order to get the required data from Xen and
provide a wrapper for libxenctrl.

Signed-off-by: Sergey Dyasli <sergey.dyasli@xxxxxxxxxx>
---
 tools/include/xenctrl.h                  |  2 ++
 tools/libs/ctrl/xc_misc.c                | 21 +++++++++++++++++
 xen/arch/x86/platform_hypercall.c        | 30 ++++++++++++++++++++++++
 xen/arch/x86/x86_64/platform_hypercall.c |  4 ++++
 xen/include/public/platform.h            | 12 ++++++++++
 xen/include/xlat.lst                     |  1 +
 6 files changed, 70 insertions(+)

diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index 8aa747dc2e..d3ef7a48a5 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -1187,6 +1187,8 @@ int xc_cputopoinfo(xc_interface *xch, unsigned *max_cpus,
                    xc_cputopo_t *cputopo);
 int xc_microcode_update(xc_interface *xch, const void *buf, size_t len);
 int xc_get_cpu_version(xc_interface *xch, struct xenpf_pcpu_version *cpu_ver);
+int xc_get_ucode_version(xc_interface *xch,
+                         struct xenpf_ucode_version *ucode_ver);
 int xc_numainfo(xc_interface *xch, unsigned *max_nodes,
                 xc_meminfo_t *meminfo, uint32_t *distance);
 int xc_pcitopoinfo(xc_interface *xch, unsigned num_devs,
diff --git a/tools/libs/ctrl/xc_misc.c b/tools/libs/ctrl/xc_misc.c
index f2f6e4348e..b93477d189 100644
--- a/tools/libs/ctrl/xc_misc.c
+++ b/tools/libs/ctrl/xc_misc.c
@@ -246,6 +246,27 @@ int xc_get_cpu_version(xc_interface *xch, struct 
xenpf_pcpu_version *cpu_ver)
     return 0;
 }
 
+int xc_get_ucode_version(xc_interface *xch,
+                         struct xenpf_ucode_version *ucode_ver)
+{
+    int ret;
+    DECLARE_PLATFORM_OP;
+
+    if ( !xch || !ucode_ver )
+        return -1;
+
+    platform_op.cmd = XENPF_get_ucode_version;
+    platform_op.u.ucode_version.xen_cpuid = ucode_ver->xen_cpuid;
+
+    ret = do_platform_op(xch, &platform_op);
+    if ( ret != 0 )
+        return ret;
+
+    *ucode_ver = platform_op.u.ucode_version;
+
+    return 0;
+}
+
 int xc_cputopoinfo(xc_interface *xch, unsigned *max_cpus,
                    xc_cputopo_t *cputopo)
 {
diff --git a/xen/arch/x86/platform_hypercall.c 
b/xen/arch/x86/platform_hypercall.c
index a2d9526355..d0818fea47 100644
--- a/xen/arch/x86/platform_hypercall.c
+++ b/xen/arch/x86/platform_hypercall.c
@@ -640,6 +640,36 @@ ret_t do_platform_op(
     }
     break;
 
+    case XENPF_get_ucode_version:
+    {
+        struct xenpf_ucode_version *ver = &op->u.ucode_version;
+
+        if ( !get_cpu_maps() )
+        {
+            ret = -EBUSY;
+            break;
+        }
+
+        if ( (ver->xen_cpuid >= nr_cpu_ids) || !cpu_online(ver->xen_cpuid) )
+        {
+            ret = -ENOENT;
+        }
+        else
+        {
+            const struct cpu_signature *sig = &per_cpu(cpu_sig, 
ver->xen_cpuid);
+
+            ver->cpu_signature = sig->sig;
+            ver->pf = sig->pf;
+            ver->ucode_revision = sig->rev;
+        }
+
+        put_cpu_maps();
+
+        if ( __copy_field_to_guest(u_xenpf_op, op, u.ucode_version) )
+            ret = -EFAULT;
+    }
+    break;
+
     case XENPF_cpu_online:
     {
         int cpu = op->u.cpu_ol.cpuid;
diff --git a/xen/arch/x86/x86_64/platform_hypercall.c 
b/xen/arch/x86/x86_64/platform_hypercall.c
index 5bf6b958d2..b876fd0c4a 100644
--- a/xen/arch/x86/x86_64/platform_hypercall.c
+++ b/xen/arch/x86/x86_64/platform_hypercall.c
@@ -28,6 +28,10 @@ CHECK_pf_pcpuinfo;
 CHECK_pf_pcpu_version;
 #undef xen_pf_pcpu_version
 
+#define xen_pf_ucode_version xenpf_ucode_version
+CHECK_pf_ucode_version;
+#undef xen_pf_pucode_version
+
 #define xen_pf_enter_acpi_sleep xenpf_enter_acpi_sleep
 CHECK_pf_enter_acpi_sleep;
 #undef xen_pf_enter_acpi_sleep
diff --git a/xen/include/public/platform.h b/xen/include/public/platform.h
index 60caa5ce7e..232df79d5f 100644
--- a/xen/include/public/platform.h
+++ b/xen/include/public/platform.h
@@ -614,6 +614,17 @@ DEFINE_XEN_GUEST_HANDLE(xenpf_symdata_t);
 typedef struct dom0_vga_console_info xenpf_dom0_console_t;
 DEFINE_XEN_GUEST_HANDLE(xenpf_dom0_console_t);
 
+#define XENPF_get_ucode_version 65
+struct xenpf_ucode_version {
+    uint32_t xen_cpuid;       /* IN:  CPU number to get the revision from.  */
+    uint32_t cpu_signature;   /* OUT: CPU signature (CPUID.1.EAX).          */
+    uint32_t pf;              /* OUT: Processor Flags.                      */
+                              /*      Only applicable to Intel.             */
+    uint32_t ucode_revision;  /* OUT: Microcode Revision.                   */
+};
+typedef struct xenpf_ucode_version xenpf_ucode_version_t;
+DEFINE_XEN_GUEST_HANDLE(xenpf_ucode_version_t);
+
 /*
  * ` enum neg_errnoval
  * ` HYPERVISOR_platform_op(const struct xen_platform_op*);
@@ -645,6 +656,7 @@ struct xen_platform_op {
         xenpf_resource_op_t           resource_op;
         xenpf_symdata_t               symdata;
         xenpf_dom0_console_t          dom0_console;
+        xenpf_ucode_version_t         ucode_version;
         uint8_t                       pad[128];
     } u;
 };
diff --git a/xen/include/xlat.lst b/xen/include/xlat.lst
index d601a8a984..164f700eb6 100644
--- a/xen/include/xlat.lst
+++ b/xen/include/xlat.lst
@@ -157,6 +157,7 @@
 ?      xenpf_pcpuinfo                  platform.h
 ?      xenpf_pcpu_version              platform.h
 ?      xenpf_resource_entry            platform.h
+?      xenpf_ucode_version             platform.h
 ?      pmu_data                        pmu.h
 ?      pmu_params                      pmu.h
 !      sched_poll                      sched.h
-- 
2.17.1