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-rw-r--r--arch/ia64/pci/fixup.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/ia64/pci/fixup.c b/arch/ia64/pci/fixup.c
new file mode 100644
index 0000000000..2bcdd7d3a1
--- /dev/null
+++ b/arch/ia64/pci/fixup.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Exceptions for specific devices. Usually work-arounds for fatal design flaws.
+ * Derived from fixup.c of i386 tree.
+ */
+
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/vgaarb.h>
+#include <linux/screen_info.h>
+#include <asm/uv/uv.h>
+
+/*
+ * Fixup to mark boot BIOS video selected by BIOS before it changes
+ *
+ * From information provided by "Jon Smirl" <jonsmirl@gmail.com>
+ *
+ * The standard boot ROM sequence for an x86 machine uses the BIOS
+ * to select an initial video card for boot display. This boot video
+ * card will have its BIOS copied to 0xC0000 in system RAM.
+ * IORESOURCE_ROM_SHADOW is used to associate the boot video
+ * card with this copy. On laptops this copy has to be used since
+ * the main ROM may be compressed or combined with another image.
+ * See pci_map_rom() for use of this flag. Before marking the device
+ * with IORESOURCE_ROM_SHADOW check if a vga_default_device is already set
+ * by either arch code or vga-arbitration; if so only apply the fixup to this
+ * already-determined primary video card.
+ */
+
+static void pci_fixup_video(struct pci_dev *pdev)
+{
+ struct pci_dev *bridge;
+ struct pci_bus *bus;
+ u16 config;
+ struct resource *res;
+
+ if (is_uv_system())
+ return;
+ /* Maybe, this machine supports legacy memory map. */
+
+ /* Is VGA routed to us? */
+ bus = pdev->bus;
+ while (bus) {
+ bridge = bus->self;
+
+ /*
+ * From information provided by
+ * "David Miller" <davem@davemloft.net>
+ * The bridge control register is valid for PCI header
+ * type BRIDGE, or CARDBUS. Host to PCI controllers use
+ * PCI header type NORMAL.
+ */
+ if (bridge && (pci_is_bridge(bridge))) {
+ pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
+ &config);
+ if (!(config & PCI_BRIDGE_CTL_VGA))
+ return;
+ }
+ bus = bus->parent;
+ }
+ if (!vga_default_device() || pdev == vga_default_device()) {
+ pci_read_config_word(pdev, PCI_COMMAND, &config);
+ if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
+ res = &pdev->resource[PCI_ROM_RESOURCE];
+
+ pci_disable_rom(pdev);
+ if (res->parent)
+ release_resource(res);
+
+ res->start = 0xC0000;
+ res->end = res->start + 0x20000 - 1;
+ res->flags = IORESOURCE_MEM | IORESOURCE_ROM_SHADOW |
+ IORESOURCE_PCI_FIXED;
+ dev_info(&pdev->dev, "Video device with shadowed ROM at %pR\n",
+ res);
+ }
+ }
+}
+DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID,
+ PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);