[pci][fdt] do not attempt to configure PCI with 64bit bars on a 32bit…

… system Especially in the case where the 32bit system doesn't have an MMU, avoid using any high addresses for BARs.
littlekernel · May 10, 2024 · 2f98fbf · 2f98fbf
1 parent 5d8dd9c
commit 2f98fbf
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Showing 2 changed files with 5 additions and 2 deletions.
diff --git a/dev/bus/pci/bus_mgr/resource.cpp b/dev/bus/pci/bus_mgr/resource.cpp
@@ -71,6 +71,7 @@ status_t resource_allocator::allocate_mmio(bool can_be_64bit, bool prefetchable,
             return NO_ERROR;
         }
 
+        // after trying once to allocate in a 64bit range, drop to 32bit and try again
         if (can_be_64bit) {
             can_be_64bit = false;
             continue;

diff --git a/lib/fdtwalk/helpers.cpp b/lib/fdtwalk/helpers.cpp
@@ -249,8 +249,10 @@ status_t fdtwalk_setup_pci(const void *fdt) {
                     if (pcie_info[i].mmio_len > 0) {
                         pci_bus_mgr_add_resource(PCI_RESOURCE_MMIO_RANGE, pcie_info[i].mmio_base, pcie_info[i].mmio_len);
                     }
-                    if (pcie_info[i].mmio64_len > 0) {
-                        pci_bus_mgr_add_resource(PCI_RESOURCE_MMIO64_RANGE, pcie_info[i].mmio64_base, pcie_info[i].mmio64_len);
+                    if (sizeof(void *) >= 8) {
+                        if (pcie_info[i].mmio64_len > 0) {
+                            pci_bus_mgr_add_resource(PCI_RESOURCE_MMIO64_RANGE, pcie_info[i].mmio64_base, pcie_info[i].mmio64_len);
+                        }
                     }
                 }
             }