x86/hpet: warn about and clear reserved set config register bits

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>

diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 7394f7456fb9588d19d2d4516b8daf9f1b27f1f6..1b9fd574e5b007b4aaf3d8053fca3b41a109c992 100644 (file)
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -755,6 +755,13 @@ void hpet_resume(u32 *boot_cfg)
     if ( boot_cfg )
         *boot_cfg = cfg;
     cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY);
+    if ( cfg )
+    {
+        printk(XENLOG_WARNING
+               "HPET: reserved bits %#x set in global config register\n",
+               cfg);
+        cfg = 0;
+    }
     hpet_write32(cfg, HPET_CFG);
 
     hpet_id = hpet_read32(HPET_ID);
@@ -765,6 +772,13 @@ void hpet_resume(u32 *boot_cfg)
         if ( boot_cfg )
             boot_cfg[i + 1] = cfg;
         cfg &= ~HPET_TN_ENABLE;
+        if ( cfg & HPET_TN_RESERVED )
+        {
+            printk(XENLOG_WARNING
+                   "HPET: reserved bits %#x set in channel %u config register\n",
+                   cfg & HPET_TN_RESERVED, i);
+            cfg &= ~HPET_TN_RESERVED;
+        }
         hpet_write32(cfg, HPET_Tn_CFG(i));
     }
 

diff --git a/xen/arch/x86/hvm/hpet.c b/xen/arch/x86/hvm/hpet.c
index 15d76471a06903f7f8018f9767f788fa8d3d5af6..4b4b9050952917ae83ffc7abdc4592395e16cea2 100644 (file)
--- a/xen/arch/x86/hvm/hpet.c
+++ b/xen/arch/x86/hvm/hpet.c
@@ -42,7 +42,8 @@
     (hvm_get_guest_time(vhpet_vcpu(hpet)) / STIME_PER_HPET_TICK)
 
 #define HPET_TN_INT_ROUTE_CAP_SHIFT 32
-#define HPET_TN_CFG_BITS_READONLY_OR_RESERVED 0xffff80b1U
+#define HPET_TN_CFG_BITS_READONLY_OR_RESERVED (HPET_TN_RESERVED | \
+    HPET_TN_PERIODIC_CAP | HPET_TN_64BIT_CAP | HPET_TN_FSB_CAP)
 
 /* can be routed to IOAPIC.redirect_table[23..20] */
 #define HPET_TN_INT_ROUTE_CAP      (0x00f00000ULL \

diff --git a/xen/include/asm-x86/hpet.h b/xen/include/asm-x86/hpet.h
index a230c94e4450fbdd3a1c8b3b21f125e68c9e0c47..f6f3b5f08a64f0f5d761802caaa043c9c19f60d3 100644 (file)
--- a/xen/include/asm-x86/hpet.h
+++ b/xen/include/asm-x86/hpet.h
@@ -43,6 +43,7 @@
 #define HPET_TN_ROUTE          0x3e00
 #define HPET_TN_FSB            0x4000
 #define HPET_TN_FSB_CAP                0x8000
+#define HPET_TN_RESERVED       0xffff0081
 #define HPET_TN_ROUTE_SHIFT    9