apci: fix PXB behaviour if used with unsupported BIOS

PXB does not work with unsupported bioses, but should not interfere with normal OS operation. We don't ship them anymore, but it's reasonable to keep the work-around until we update the bios in qemu. Fix this by not adding PXB mem/IO chunks to _CRS if they weren't configured by BIOS. Signed-off-by: Marcel Apfelbaum <marcel@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Laszlo Ersek <lersek@redhat.com>
qemu · Jun 3, 2015 · 0f6dd8e · 0f6dd8e
1 parent 0e79e51
commit 0f6dd8e
Showing 1 changed file with 58 additions and 29 deletions.
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
@@ -786,6 +786,14 @@ static Aml *build_crs(PCIHostState *host,
             range_base = r->addr;
             range_limit = r->addr + r->size - 1;
 
+            /*
+             * Work-around for old bioses
+             * that do not support multiple root buses
+             */
+            if (!range_base || range_base > range_limit) {
+                continue;
+            }
+
             if (r->type & PCI_BASE_ADDRESS_SPACE_IO) {
                 aml_append(crs,
                     aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
@@ -819,45 +827,66 @@ static Aml *build_crs(PCIHostState *host,
 
             range_base = pci_bridge_get_base(dev, PCI_BASE_ADDRESS_SPACE_IO);
             range_limit = pci_bridge_get_limit(dev, PCI_BASE_ADDRESS_SPACE_IO);
-            aml_append(crs,
-                aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
-                            AML_POS_DECODE, AML_ENTIRE_RANGE,
-                            0,
-                            range_base,
-                            range_limit,
-                            0,
-                            range_limit - range_base + 1));
-            crs_range_insert(io_ranges, range_base, range_limit);
+
+            /*
+             * Work-around for old bioses
+             * that do not support multiple root buses
+             */
+            if (range_base || range_base > range_limit) {
+                aml_append(crs,
+                           aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
+                                       AML_POS_DECODE, AML_ENTIRE_RANGE,
+                                       0,
+                                       range_base,
+                                       range_limit,
+                                       0,
+                                       range_limit - range_base + 1));
+                crs_range_insert(io_ranges, range_base, range_limit);
+            }
 
             range_base =
                 pci_bridge_get_base(dev, PCI_BASE_ADDRESS_SPACE_MEMORY);
             range_limit =
                 pci_bridge_get_limit(dev, PCI_BASE_ADDRESS_SPACE_MEMORY);
-            aml_append(crs,
-                aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
-                                 AML_MAX_FIXED, AML_NON_CACHEABLE,
-                                 AML_READ_WRITE,
-                                 0,
-                                 range_base,
-                                 range_limit,
-                                 0,
-                                 range_limit - range_base + 1));
-            crs_range_insert(mem_ranges, range_base, range_limit);
+
+            /*
+             * Work-around for old bioses
+             * that do not support multiple root buses
+             */
+            if (range_base || range_base > range_limit) {
+                aml_append(crs,
+                           aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
+                                            AML_MAX_FIXED, AML_NON_CACHEABLE,
+                                            AML_READ_WRITE,
+                                            0,
+                                            range_base,
+                                            range_limit,
+                                            0,
+                                            range_limit - range_base + 1));
+                crs_range_insert(mem_ranges, range_base, range_limit);
+          }
 
             range_base =
                 pci_bridge_get_base(dev, PCI_BASE_ADDRESS_MEM_PREFETCH);
             range_limit =
                 pci_bridge_get_limit(dev, PCI_BASE_ADDRESS_MEM_PREFETCH);
-            aml_append(crs,
-                aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
-                                 AML_MAX_FIXED, AML_NON_CACHEABLE,
-                                 AML_READ_WRITE,
-                                 0,
-                                 range_base,
-                                 range_limit,
-                                 0,
-                                 range_limit - range_base + 1));
-            crs_range_insert(mem_ranges, range_base, range_limit);
+
+            /*
+             * Work-around for old bioses
+             * that do not support multiple root buses
+             */
+            if (range_base || range_base > range_limit) {
+                aml_append(crs,
+                           aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
+                                            AML_MAX_FIXED, AML_NON_CACHEABLE,
+                                            AML_READ_WRITE,
+                                            0,
+                                            range_base,
+                                            range_limit,
+                                            0,
+                                            range_limit - range_base + 1));
+                crs_range_insert(mem_ranges, range_base, range_limit);
+            }
         }
     }