q35: implement SMRAM.D_LCK

Once the SMRAM.D_LCK bit has been set by the guest several bits in SMRAM
and ESMRAMC become readonly until the next machine reset.  Implement
this by updating the wmask accordingly when the guest sets the lock bit.
As the lock it itself is locked down too we don't need to worry about
the guest clearing the lock bit.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index 14e5aebee6108058c741d93a9f12f5ce848bf7ab..305994bc383a001cdc719cc80042e9464c04c172 100644 (file)
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -268,6 +268,13 @@ static void mch_update_smram(MCHPCIState *mch)
     PCIDevice *pd = PCI_DEVICE(mch);
     bool h_smrame = (pd->config[MCH_HOST_BRIDGE_ESMRAMC] & MCH_HOST_BRIDGE_ESMRAMC_H_SMRAME);
 
+    /* implement SMRAM.D_LCK */
+    if (pd->config[MCH_HOST_BRIDGE_SMRAM] & MCH_HOST_BRIDGE_SMRAM_D_LCK) {
+        pd->config[MCH_HOST_BRIDGE_SMRAM] &= ~MCH_HOST_BRIDGE_SMRAM_D_OPEN;
+        pd->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK_LCK;
+        pd->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK_LCK;
+    }
+
     memory_region_transaction_begin();
 
     if (pd->config[MCH_HOST_BRIDGE_SMRAM] & SMRAM_D_OPEN) {
@@ -297,7 +304,6 @@ static void mch_write_config(PCIDevice *d,
 {
     MCHPCIState *mch = MCH_PCI_DEVICE(d);
 
-    /* XXX: implement SMRAM.D_LOCK */
     pci_default_write_config(d, address, val, len);
 
     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_PAM0,

diff --git a/include/hw/pci-host/q35.h b/include/hw/pci-host/q35.h
index 01b8492551fcc0cdac2be819e282dd2136a7818c..113cbe81902ed2cf4fb14093d33791fc9eee5877 100644 (file)
--- a/include/hw/pci-host/q35.h
+++ b/include/hw/pci-host/q35.h
@@ -145,6 +145,8 @@ typedef struct Q35PCIHost {
      MCH_HOST_BRIDGE_SMRAM_D_CLS |              \
      MCH_HOST_BRIDGE_SMRAM_D_LCK |              \
      MCH_HOST_BRIDGE_SMRAM_G_SMRAME)
+#define MCH_HOST_BRIDGE_SMRAM_WMASK_LCK         \
+    MCH_HOST_BRIDGE_SMRAM_D_CLS
 
 #define MCH_HOST_BRIDGE_ESMRAMC                0x9e
 #define MCH_HOST_BRIDGE_ESMRAMC_H_SMRAME       ((uint8_t)(1 << 7))
@@ -165,6 +167,7 @@ typedef struct Q35PCIHost {
     (MCH_HOST_BRIDGE_ESMRAMC_H_SMRAME |             \
      MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_MASK |         \
      MCH_HOST_BRIDGE_ESMRAMC_T_EN)
+#define MCH_HOST_BRIDGE_ESMRAMC_WMASK_LCK     0
 
 /* D1:F0 PCIE* port*/
 #define MCH_PCIE_DEV                           1