nb/intel/gm45: Use common code for SMM in TSEG

This makes i82801ix use the common smm southbridge code to set up smm
relocation and smi handler setup. This is needed in this change for the
the smm relocation code relies on some southbridge functions provided
in the common code. Some of the old code is kept for the Q35 qemu
target.

This also caches the TSEG region and therefore increases MTRR usage a
little in some cases.

Currently SMRR msr's are not set on model_1067x and model_6fx since this needs
the MSRR enable bit and lock set in IA32_FEATURE_CONTROL. This will be handled
properly in the subsequent parallel mp init patchset.

Tested on Thinkpad X200: boots and going to and resuming from S3 still
works fine.

Change-Id: Ic80c65ea42fcf554ea5695772e8828d2f3b00b98
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/23419
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 5 insertions, 7 deletions

diff --git a/src/northbridge/intel/gm45/ram_calc.c b/src/northbridge/intel/gm45/ram_calc.c
index 011d90347b..0e953419fe 100644
--- a/src/northbridge/intel/gm45/ram_calc.c
+++ b/src/northbridge/intel/gm45/ram_calc.c
@@ -83,7 +83,7 @@ u32 decode_tseg_size(u8 esmramc)
 	}
 }
 
-static uintptr_t smm_region_start(void)
+uintptr_t smm_region_start(void)
 {
 	const pci_devfn_t dev = PCI_DEV(0, 0, 0);
 
@@ -135,14 +135,12 @@ void platform_enter_postcar(void)
 	/* Cache RAM as WB from 0 -> CACHE_TMP_RAMTOP. */
 	postcar_frame_add_mtrr(&pcf, 0, CACHE_TMP_RAMTOP, MTRR_TYPE_WRBACK);
 
-	/* Cache two separate 4 MiB regions below the top of ram, this
-	 * satisfies MTRR alignment requirements. If you modify this to
-	 * cover TSEG, make sure UMA region is not set with WRBACK as it
-	 * causes hard-to-recover boot failures.
+	/* Cache a 8 MiB region below the top of ram and 8 MiB above top of
+	 * ram to cover both cbmem as the TSEG region.
 	 */
 	top_of_ram = (uintptr_t)cbmem_top();
-	postcar_frame_add_mtrr(&pcf, top_of_ram - 4*MiB, 4*MiB, MTRR_TYPE_WRBACK);
-	postcar_frame_add_mtrr(&pcf, top_of_ram - 8*MiB, 4*MiB, MTRR_TYPE_WRBACK);
+	postcar_frame_add_mtrr(&pcf, top_of_ram - 8*MiB, 16*MiB,
+			MTRR_TYPE_WRBACK);
 
 	run_postcar_phase(&pcf);