x86: UV runtime bios calls v4

[PATCH 0/4] x86: UV runtime bios calls v4

Purpose:
Create an interface to allow calls into bios to return platform specific information. The interface adds a new EFI table entry for UV. EFI provides a mechanism for defining function pointers to firmware routines. This patchset builds on the EFI mechanism to provide access to those firmware routines for UV.

Version 4 changes:
Undo the version 3 changes.
Move implementation without CONFIG_EFI defined out of CONFIG_X86_32 block.
Add Acked-by: Huang Ying <[email protected]>

Version 3 changes:
Add function (oem) to efi_runtime_services_t, replacing uv_systab. Use efi_call_virt<n>.
Remove efi_call<n> stubs.

Version 2 changes:
Add uv_systab to efi struct.
Define efi_call* stubs in include/asm-x86/uv/bios.h. Made symbols EXPORT_SYMBOL_GPL().
Added check for failure on sysfs_create_file() calls. Other code style changes.

Patches:
uv_efi_bios: Look for UV entry in EFI tables.

uv_bios_common: Add the EFI callback function using the EFI table
entry. Create associated wrapper code. Initialize UV system table entry info at boot time.

uv_bios_call_partition: Add call to get partitioning related info.

uv_sysfs: Create sysfs entrys in /sys/firmware/sgi_uv/ for
partitioning related information.

Implementation comments:

This patch adds a new EFI entry type (uv_systab).

The location in sysfs (/sys/firmware/sgi_uv/) is based on community feedback. The interface is documented in Documentation/ABI/testing/sysfs-firmware-sgi_uv.

If EFI is not configured (CONFIG_EFI), the calls will return -ENOSYS. If run on a system with a bios that does not support EFI UV, the calls will return -ENOSYS.

Paul Jackson assisted in the development of this code.

Russ Anderson, OS RAS/Partitioning Project Lead  
SGI - Silicon Graphics Inc          [email protected]