Old routine copied all of CAR region as-is right below CONFIG_RAMTOP.
Most of this region was reserved to interleave AP CPU address spaces
and unused on BSP CPU. The only part of CAR region requiring a copy
in RAM is the sysinfo structure.
Improved routine changes this as follows:
A region of size 'backup_size' below CONFIG_RAMTOP is cleared. In
case of S3 resume, OS context from this region is first copied to
high memory (CBMEM_ID_RESUME).
At stack switch, CAR stack is discarded. Top of the stack for BSP
is located at 'CONFIG_RAMTOP - car_size' for the remaining part
of the romstage. This region is part of 'backup_size' and was zeroed
before the switch took place.
Before CAR is torn down the region of CAR_GLOBALS (and CAR_CBMEM),
including the relevant sysinfo data for AP nodes memory training,
is copied at 'CONFIG_RAMTOP - car_size'.
NOTE: While CAR_GLOBAL variables are recovered, there are currently
no means to calculate their offsets in RAM.
NOTE: Boards with multiple CPU packages are likely already broken since
bbc880ee amdk8/amdfam10: Use CAR_GLOBAL for sysinfo
This moved the copy of sysinfo in RAM from above the stack to below
the stack, but code for AP CPU's was not adjusted accordingly.
Change-Id: Ie45b576aec6a2e006bfcb26b52fdb77c24f72e3b
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/4583
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
abc083e06b