Basic HPET MSI setup code. Routines to perform basic MSI read write
in HPET memory map and setting up irq_chip for HPET MSI.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>