x86: UV runtime bios calls

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

Purpose:
Create an interface to allow calls into bios to return platform specific information. The interface uses EFI SAL table entry. 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.

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

uv_bios_common: Add the EFI callback function using the EFI table
entry. Create associated wrapper code. Initialize SAL 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 uses sal_systab. sal_systab is used on ia64, but was not used on x86. An alternative would be to create a new EFI entry type (uv_systab), though that would require adding to struct efi.

The location in sysfs (/sys/firmware/sgi_uv/) is based on community feedback.

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