Changeset 64459 in vbox for trunk/src/VBox

Timestamp:

Oct 28, 2016 2:12:20 PM (8 years ago)

Author:

vboxsync

Message:

DevPci: Cleaning up ich9pciConfigWriteDev.

File:

• trunk/src/VBox/Devices/Bus/DevPciIch9.cpp (modified) (12 diffs)

trunk/src/VBox/Devices/Bus/DevPciIch9.cpp

@@ -1999 +1999 @@
         {
             /*
-             * Handle the writes byte-by-byte.
+             * Handle the writes byte-by-byte to catch all possible cases.
+             *
+             * Note! Real hardware may not necessarily handle non-dword writes like
+             *       we do here and even produce erratic behavior.  We don't (yet)
+             *       try emulate that.
              */
             bool     fUpdateMappings = false;
@@ -2006 +2010 @@
             while (cb-- > 0)
             {
+                /*
+                 * Check writability first.
+                 */
                 bool fWritable = false;
                 switch (bHeaderType)
@@ -2013 +2020 @@
                         switch (uAddress)
                         {
-                            /* Read-only registers  */
+                            /* Read-only registers. */
                             case VBOX_PCI_VENDOR_ID:
                             case VBOX_PCI_VENDOR_ID+1:
@@ -2035 +2042 @@
                                 fWritable = false;
                                 break;
-                            /* Others can be written */
+                            /* Other registers can be written. */
                             default:
                                 fWritable = true;
@@ -2045 +2052 @@
                         switch (uAddress)
                         {
-                            /* Read-only registers */
+                            /* Read-only registers. */
                             case VBOX_PCI_VENDOR_ID:
                             case VBOX_PCI_VENDOR_ID+1:
@@ -2062 +2069 @@
                                 fWritable = false;
                                 break;
+                            /* Other registers can be written. */
                             default:
                                 fWritable = true;
@@ -2068 +2076 @@
                         break;
                     default:
-                        AssertMsgFailed(("Unknown header type %x\n", PCIDevGetHeaderType(pPciDev)));
+                        AssertMsgFailed(("Unknown header type %#x\n", bHeaderType));
                         fWritable = false;
                         break;
@@ -2078 +2086 @@
                 {
                     case VBOX_PCI_COMMAND: /* Command register, bits 0-7. */
-                        fUpdateMappings = true;
-                        goto l_default_case;
+                        if (fWritable)
+                        {
+                            PCIDevSetByte(pPciDev, uAddress, bVal);
+                            fUpdateMappings = true; /** @todo r=bird: Probably not necessary to update mappings on VBOX_PCI_COMMAND changes for bridges? */
+                        }
+                        break;
+
                     case VBOX_PCI_COMMAND+1: /* Command register, bits 8-15. */
-                        /* don't change reserved bits (11-15) */
-                        bVal &= ~UINT32_C(0xf8);
-                        fUpdateMappings = true;
-                        goto l_default_case;
+                        if (fWritable)
+                        {
+                            /* don't change reserved bits (11-15) */
+                            bVal &= ~UINT32_C(0xf8);
+                            PCIDevSetByte(pPciDev, uAddress, bVal);
+                            fUpdateMappings = true;
+                        }
+                        break;
+
                     case VBOX_PCI_STATUS:  /* Status register, bits 0-7. */
                         /* don't change read-only bits => actually all lower bits are read-only */
@@ -2091 +2109 @@
                         pPciDev->abConfig[uAddress] &= ~bVal;
                         break;
+
                     case VBOX_PCI_STATUS+1:  /* Status register, bits 8-15. */
                         /* don't change read-only bits */
@@ -2097 +2116 @@
                         pPciDev->abConfig[uAddress] &= ~bVal;
                         break;
+
                     case VBOX_PCI_ROM_ADDRESS:    case VBOX_PCI_ROM_ADDRESS   +1: case VBOX_PCI_ROM_ADDRESS   +2: case VBOX_PCI_ROM_ADDRESS   +3:
                         fRom = true;
@@ -2109 +2129 @@
                         {
                             uint32_t iRegion = fRom ? VBOX_PCI_ROM_SLOT : (uAddress - VBOX_PCI_BASE_ADDRESS_0) >> 2;
-                            uint32_t off     = uAddress & 0x3;
-                            ich9pciWriteBarByte(pPciDev, iRegion, off, bVal);
+                            ich9pciWriteBarByte(pPciDev, iRegion, uAddress & 0x3, bVal);
                             fUpdateMappings = true;
                             break;
@@ -2116 +2135 @@
                         /* fall thru (bridge) */
                     default:
-                    l_default_case:
                         if (fWritable)
                             PCIDevSetByte(pPciDev, uAddress, bVal);