soc/intel/apollolake: bootblock: implement platform_prog_run()

Once bootblock copied romstage into CAR it may not jump into it right
away. This is because we are in NEM mode, there is no backing store
and a miss in L1 may cause L1D line snoop that gets written back. The
solution is to flush L1D to L2 so snoop guaranteed to hit L2.

Change-Id: I2ffe46dbfdfe7f0ccd38b34ff203ff76b6d5755b
Signed-off-by: Andrey Petrov <andrey.petrov@intel.com>
Reviewed-on: https://review.coreboot.org/13703
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/soc/intel/apollolake/bootblock/bootblock.c b/src/soc/intel/apollolake/bootblock/bootblock.c
index d3a78e106f..500761315b 100644
--- a/src/soc/intel/apollolake/bootblock/bootblock.c
+++ b/src/soc/intel/apollolake/bootblock/bootblock.c
@@ -12,7 +12,9 @@
 #include <arch/cpu.h>
 #include <bootblock_common.h>
 #include <device/pci.h>
+#include <program_loading.h>
 #include <soc/bootblock.h>
+#include <soc/cpu.h>
 #include <soc/northbridge.h>
 #include <soc/pci_devs.h>
 
@@ -32,3 +34,11 @@ void asmlinkage bootblock_c_entry(void)
 	/* Call lib/bootblock.c main */
 	main();
 }
+
+void platform_prog_run(struct prog *prog)
+{
+	/* Flush L1D cache to L2 */
+	msr_t msr = rdmsr(MSR_POWER_MISC);
+	msr.lo |= (1 << 8);
+	wrmsr(MSR_POWER_MISC, msr);
+}