MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
authorBjorn Helgaas <bhelgaas@google.com>
Thu, 3 Mar 2016 03:42:04 +0000 (21:42 -0600)
committerBjorn Helgaas <bhelgaas@google.com>
Sat, 12 Mar 2016 12:00:29 +0000 (06:00 -0600)
Loongson 3 used the IORESOURCE_ROM_COPY flag for its ROM resource.  There
are two problems with this:

  - When IORESOURCE_ROM_COPY is set, pci_map_rom() assumes the resource
    contains virtual addresses, so it doesn't ioremap the resource.  This
    implies loongson_sysconf.vgabios_addr is a virtual address.  That's a
    problem because resources should contain CPU *physical* addresses not
    virtual addresses.

  - When IORESOURCE_ROM_COPY is set, pci_cleanup_rom() calls kfree() on the
    resource.  We did not kmalloc() the loongson_sysconf.vgabios_addr area,
    so it is incorrect to kfree() it.

If we're using a shadow copy in RAM for the Loongson 3 VGA BIOS area,
disable the ROM BAR and release the address space it was consuming.

Use IORESOURCE_ROM_SHADOW instead of IORESOURCE_ROM_COPY.  This means the
struct resource contains CPU physical addresses, and pci_map_rom() will
ioremap() it as needed.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
arch/mips/pci/fixup-loongson3.c

index b66b1eb15ae8be906b92ebaa712b468a4250d226..2b6d5e196f9990255eb5d35de3e6580a69f6003f 100644 (file)
@@ -48,9 +48,14 @@ static void pci_fixup_radeon(struct pci_dev *pdev)
        if (!loongson_sysconf.vgabios_addr)
                return;
 
-       res->start = loongson_sysconf.vgabios_addr;
+       pci_disable_rom(pdev);
+       if (res->parent)
+               release_resource(res);
+
+       res->start = virt_to_phys((void *) loongson_sysconf.vgabios_addr);
        res->end   = res->start + 256*1024 - 1;
-       res->flags |= IORESOURCE_ROM_COPY;
+       res->flags = IORESOURCE_MEM | IORESOURCE_ROM_SHADOW |
+                    IORESOURCE_PCI_FIXED;
 
        dev_info(&pdev->dev, "BAR %d: assigned %pR for Radeon ROM\n",
                 PCI_ROM_RESOURCE, res);