[SeaBIOS] [PATCH 6/6] pci: map 64-bit BARs at location provided by emulator

[Igor Mammedov]

On Tue, 26 Nov 2013 13:24:14 +0100
Gerd Hoffmann <kraxel at redhat.com> wrote:

> Currently 64-bit PCI BARs are unconditionally mapped by BIOS right
> over 4G + RamSizeOver4G location, which doesn't allow to reserve
> extra space before 64-bit PCI window. For memory hotplug an extra
> RAM space might be reserved after present 64-bit RAM end and BIOS
> should map 64-bit PCI BARs after it.
> 
> Introduce "etc/reserved-memory-end" romfile to provide BIOS a hint
> where it should start mapping of 64-bit PCI BARs. If romfile is
> missing, BIOS reverts to legacy behavior and starts mapping after
> high memory.
> 
> Based-on-patch-by: Igor Mammedov <imammedo at redhat.com>
> Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
> ---
>  src/fw/pciinit.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c
> index 3de0c7e..654697d 100644
> --- a/src/fw/pciinit.c
> +++ b/src/fw/pciinit.c
> @@ -19,6 +19,8 @@
>  #include "string.h" // memset
>  #include "util.h" // pci_setup
>  #include "x86.h" // outb
> +#include "byteorder.h" // le64_to_cpu
> +#include "romfile.h" // romfile_loadint
>  
>  #define PCI_DEVICE_MEM_MIN    (1<<12)  // 4k == page size
>  #define PCI_BRIDGE_MEM_MIN    (1<<21)  // 2M == hugepage size
> @@ -788,7 +790,9 @@ static void pci_bios_map_devices(struct pci_bus *busses)
>          u64 align_mem = pci_region_align(&r64_mem);
>          u64 align_pref = pci_region_align(&r64_pref);
>  
> -        r64_mem.base = 0x100000000LL + RamSizeOver4G;
> +        r64_mem.base = le64_to_cpu(romfile_loadint("etc/reserved-memory-end", 0));
> +        if (r64_mem.base < 0x100000000LL + RamSizeOver4G)
> +            r64_mem.base = 0x100000000LL + RamSizeOver4G;
>          r64_mem.base = ALIGN(r64_mem.base, align_mem);
>          r64_mem.base = ALIGN(r64_mem.base, (1LL<<30));    // 1G hugepage
>          r64_pref.base = r64_mem.base + sum_mem;

Reviewed-By: Igor Mammedov <imammedo at redhat.com>