[Qemu-devel] [PULL 16/38] s390x/cpumodel: introduce CPU feature group definitions

[Cornelia Huck <cornelia.huck@de.ibm.com>]

From: David Hildenbrand <dahi@linux.vnet.ibm.com>

Let's use the generated groups to create feature group representations for
the user. These groups can later be used to enable/disable multiple
features in one shot and will be used to reduce the amount of reported
features to the user if all subfeatures are in place.

We want to work on features using ordinary bitmap operations, however we
can't initialize a bitmap statically (unsigned long[] ...). Therefore
we store the generated feature lists in separate arrays and convert
them to a proper bitmaps before they will ever be used.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <20160905085244.99980-8-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
 target-s390x/cpu_features.c | 58 ++++++++++++++++++++++++++++++++++++++++++++-
 target-s390x/cpu_features.h | 24 +++++++++++++++++++
 2 files changed, 81 insertions(+), 1 deletion(-)

diff --git a/target-s390x/cpu_features.c b/target-s390x/cpu_features.c
index 1d285ce..42fd9d7 100644
--- a/target-s390x/cpu_features.c
+++ b/target-s390x/cpu_features.c
@@ -11,7 +11,9 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/module.h"
 #include "cpu_features.h"
+#include "gen-features.h"
 
 #define FEAT_INIT(_name, _type, _bit, _desc) \
     {                                                \
@@ -335,14 +337,68 @@ void s390_add_from_feat_block(S390FeatBitmap features, S390FeatType type,
     }
 }
 
-void s390_feat_bitmap_to_ascii(const S390FeatBitmap bitmap, void *opaque,
+void s390_feat_bitmap_to_ascii(const S390FeatBitmap features, void *opaque,
                                void (*fn)(const char *name, void *opaque))
 {
+    S390FeatBitmap bitmap, tmp;
+    S390FeatGroup group;
     S390Feat feat;
 
+    bitmap_copy(bitmap, features, S390_FEAT_MAX);
+
+    /* process whole groups first */
+    for (group = 0; group < S390_FEAT_GROUP_MAX; group++) {
+        const S390FeatGroupDef *def = s390_feat_group_def(group);
+
+        bitmap_and(tmp, bitmap, def->feat, S390_FEAT_MAX);
+        if (bitmap_equal(tmp, def->feat, S390_FEAT_MAX)) {
+            bitmap_andnot(bitmap, bitmap, def->feat, S390_FEAT_MAX);
+            fn(def->name, opaque);
+        }
+    }
+
+    /* report leftovers as separate features */
     feat = find_first_bit(bitmap, S390_FEAT_MAX);
     while (feat < S390_FEAT_MAX) {
         fn(s390_feat_def(feat)->name, opaque);
         feat = find_next_bit(bitmap, S390_FEAT_MAX, feat + 1);
     };
 }
+
+#define FEAT_GROUP_INIT(_name, _group, _desc)        \
+    {                                                \
+        .name = _name,                               \
+        .desc = _desc,                               \
+        .init = { S390_FEAT_GROUP_LIST_ ## _group }, \
+    }
+
+/* indexed by feature group number for easy lookup */
+static S390FeatGroupDef s390_feature_groups[] = {
+    FEAT_GROUP_INIT("plo", PLO, "Perform-locked-operation facility"),
+    FEAT_GROUP_INIT("tods", TOD_CLOCK_STEERING, "Tod-clock-steering facility"),
+    FEAT_GROUP_INIT("gen13ptff", GEN13_PTFF, "PTFF enhancements introduced with z13"),
+    FEAT_GROUP_INIT("msa", MSA, "Message-security-assist facility"),
+    FEAT_GROUP_INIT("msa1", MSA_EXT_1, "Message-security-assist-extension 1 facility"),
+    FEAT_GROUP_INIT("msa2", MSA_EXT_2, "Message-security-assist-extension 2 facility"),
+    FEAT_GROUP_INIT("msa3", MSA_EXT_3, "Message-security-assist-extension 3 facility"),
+    FEAT_GROUP_INIT("msa4", MSA_EXT_4, "Message-security-assist-extension 4 facility"),
+    FEAT_GROUP_INIT("msa5", MSA_EXT_5, "Message-security-assist-extension 5 facility"),
+};
+
+const S390FeatGroupDef *s390_feat_group_def(S390FeatGroup group)
+{
+    return &s390_feature_groups[group];
+}
+
+static void init_groups(void)
+{
+    int i;
+
+    /* init all bitmaps from gnerated data initially */
+    for (i = 0; i < ARRAY_SIZE(s390_feature_groups); i++) {
+        s390_init_feat_bitmap(s390_feature_groups[i].init,
+                              s390_feature_groups[i].feat);
+    }
+}
+
+type_init(init_groups)
diff --git a/target-s390x/cpu_features.h b/target-s390x/cpu_features.h
index c69ba36..d669121 100644
--- a/target-s390x/cpu_features.h
+++ b/target-s390x/cpu_features.h
@@ -63,6 +63,30 @@ void s390_add_from_feat_block(S390FeatBitmap features, S390FeatType type,
 void s390_feat_bitmap_to_ascii(const S390FeatBitmap features, void *opaque,
                                void (*fn)(const char *name, void *opaque));
 
+/* static groups that will never change */
+typedef enum {
+    S390_FEAT_GROUP_PLO,
+    S390_FEAT_GROUP_TOD_CLOCK_STEERING,
+    S390_FEAT_GROUP_GEN13_PTFF_ENH,
+    S390_FEAT_GROUP_MSA,
+    S390_FEAT_GROUP_MSA_EXT_1,
+    S390_FEAT_GROUP_MSA_EXT_2,
+    S390_FEAT_GROUP_MSA_EXT_3,
+    S390_FEAT_GROUP_MSA_EXT_4,
+    S390_FEAT_GROUP_MSA_EXT_5,
+    S390_FEAT_GROUP_MAX,
+} S390FeatGroup;
+
+/* Definition of a CPU feature group */
+typedef struct {
+    const char *name;       /* name exposed to the user */
+    const char *desc;       /* description exposed to the user */
+    S390FeatBitmap feat;    /* features contained in the group */
+    S390FeatInit init;      /* used to init feat from generated data */
+} S390FeatGroupDef;
+
+const S390FeatGroupDef *s390_feat_group_def(S390FeatGroup group);
+
 #define BE_BIT_NR(BIT) (BIT ^ (BITS_PER_LONG - 1))
 #define BE_BIT(BIT) (1ULL < BE_BIT_NR(BIT))
 
-- 
2.9.3