x86: refactor psr: L3 CAT: implement get value flow.

There is an interface in user space to show feature value of
domains.

This patch implements get value flow in hypervisor.

It also changes domctl interface to make it more general.

With this patch, 'psr-cat-show' can work for L3 CAT but not for
L3 code/data which is implemented in CDP related patches.

Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/domctl.c

@@ -1442,6 +1442,8 @@ long arch_do_domctl(
     case XEN_DOMCTL_psr_cat_op:
         switch ( domctl->u.psr_cat_op.cmd )
         {
+            uint32_t val32;
+
         case XEN_DOMCTL_PSR_CAT_OP_SET_L3_CBM:
             ret = psr_set_l3_cbm(d, domctl->u.psr_cat_op.target,
                                  domctl->u.psr_cat_op.data,
@@ -1461,23 +1463,23 @@ long arch_do_domctl(
             break;
 
         case XEN_DOMCTL_PSR_CAT_OP_GET_L3_CBM:
-            ret = psr_get_l3_cbm(d, domctl->u.psr_cat_op.target,
-                                 &domctl->u.psr_cat_op.data,
-                                 PSR_CBM_TYPE_L3);
+            ret = psr_get_val(d, domctl->u.psr_cat_op.target,
+                              &val32, PSR_CBM_TYPE_L3);
+            domctl->u.psr_cat_op.data = val32;
             copyback = true;
             break;
 
         case XEN_DOMCTL_PSR_CAT_OP_GET_L3_CODE:
-            ret = psr_get_l3_cbm(d, domctl->u.psr_cat_op.target,
-                                 &domctl->u.psr_cat_op.data,
-                                 PSR_CBM_TYPE_L3_CODE);
+            ret = psr_get_val(d, domctl->u.psr_cat_op.target,
+                              &val32, PSR_CBM_TYPE_L3_CODE);
+            domctl->u.psr_cat_op.data = val32;
             copyback = true;
             break;
 
         case XEN_DOMCTL_PSR_CAT_OP_GET_L3_DATA:
-            ret = psr_get_l3_cbm(d, domctl->u.psr_cat_op.target,
-                                 &domctl->u.psr_cat_op.data,
-                                 PSR_CBM_TYPE_L3_DATA);
+            ret = psr_get_val(d, domctl->u.psr_cat_op.target,
+                              &val32, PSR_CBM_TYPE_L3_DATA);
+            domctl->u.psr_cat_op.data = val32;
             copyback = true;
             break;
 

xen/arch/x86/psr.c

@@ -524,10 +524,55 @@ int psr_get_info(unsigned int socket, enum cbm_type type,
     return -EINVAL;
 }
 
-int psr_get_l3_cbm(struct domain *d, unsigned int socket,
-                   uint64_t *cbm, enum cbm_type type)
+int psr_get_val(struct domain *d, unsigned int socket,
+                uint32_t *val, enum cbm_type type)
 {
-    return 0;
+    const struct psr_socket_info *info = get_socket_info(socket);
+    const struct feat_node *feat;
+    enum psr_feat_type feat_type;
+    unsigned int cos, i;
+
+    ASSERT(val);
+
+    if ( IS_ERR(info) )
+        return PTR_ERR(info);
+
+    feat_type = psr_cbm_type_to_feat_type(type);
+    if ( feat_type >= ARRAY_SIZE(info->features) )
+        return -ENOENT;
+
+    feat = info->features[feat_type];
+    if ( !feat )
+        return -ENOENT;
+
+    if ( !feat_props[feat_type] )
+    {
+        ASSERT_UNREACHABLE();
+        return -ENOENT;
+    }
+
+    cos = d->arch.psr_cos_ids[socket];
+    /*
+     * If input cos exceeds current feature's cos_max, we should return its
+     * default value which is stored in cos 0. This case only happens
+     * when more than two features enabled concurrently and at least one
+     * features's cos_max is bigger than others. When a domain's working cos
+     * id is bigger than some features' cos_max, HW automatically works as
+     * default value for those features which cos_max is smaller.
+     */
+    if ( cos > feat->cos_max )
+        cos = 0;
+
+    for ( i = 0; i < feat_props[feat_type]->cos_num; i++ )
+    {
+        if ( type == feat_props[feat_type]->type[i] )
+        {
+            *val = feat->cos_reg_val[cos * feat_props[feat_type]->cos_num + i];
+            return 0;
+        }
+    }
+
+    return -EINVAL;
 }
 
 int psr_set_l3_cbm(struct domain *d, unsigned int socket,

xen/include/asm-x86/psr.h

@@ -72,8 +72,8 @@ void psr_ctxt_switch_to(struct domain *d);
 
 int psr_get_info(unsigned int socket, enum cbm_type type,
                  uint32_t data[], unsigned int array_len);
-int psr_get_l3_cbm(struct domain *d, unsigned int socket,
-                   uint64_t *cbm, enum cbm_type type);
+int psr_get_val(struct domain *d, unsigned int socket,
+                uint32_t *val, enum cbm_type type);
 int psr_set_l3_cbm(struct domain *d, unsigned int socket,
                    uint64_t cbm, enum cbm_type type);