soc/amd: factor out common SMM relocation code

The common code gets moved to soc/amd/common/block/cpu/smm, since it is
related to the CPU cores and soc/amd/common/block/smi is about the SMI/
SCI functionality in the FCH part. Also relocation_handler gets renamed
to smm_relocation_handler to keep it clear what it does, since it got
moved to another compilation unit.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I45224131dfd52247018c5ca19cb37c44062b03eb
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50462
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

4 files changed, 72 insertions, 0 deletions

diff --git a/src/soc/amd/common/block/cpu/Kconfig b/src/soc/amd/common/block/cpu/Kconfig
index c155975590..996605e7f3 100644
--- a/src/soc/amd/common/block/cpu/Kconfig
+++ b/src/soc/amd/common/block/cpu/Kconfig
@@ -28,6 +28,12 @@ config MEMLAYOUT_LD_FILE
 
 endif # SOC_AMD_COMMON_BLOCK_NONCAR
 
+config SOC_AMD_COMMON_BLOCK_SMM
+	bool
+	default n
+	help
+	  Add common SMM relocation and handler functionality to the build.
+
 config SOC_AMD_COMMON_BLOCK_TSC_FAM17H_19H
 	bool
 	select COLLECT_TIMESTAMPS_NO_TSC # selected use SoC-specific timestamp function
diff --git a/src/soc/amd/common/block/cpu/smm/Makefile.inc b/src/soc/amd/common/block/cpu/smm/Makefile.inc
new file mode 100644
index 0000000000..0639890207
--- /dev/null
+++ b/src/soc/amd/common/block/cpu/smm/Makefile.inc
@@ -0,0 +1,5 @@
+ifeq ($(CONFIG_SOC_AMD_COMMON_BLOCK_SMM),y)
+
+ramstage-y += smm_relocate.c
+
+endif # CONFIG_SOC_AMD_COMMON_BLOCK_SMM
diff --git a/src/soc/amd/common/block/cpu/smm/smm_relocate.c b/src/soc/amd/common/block/cpu/smm/smm_relocate.c
new file mode 100644
index 0000000000..1d7cc68d68
--- /dev/null
+++ b/src/soc/amd/common/block/cpu/smm/smm_relocate.c
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <amdblocks/smm.h>
+#include <console/console.h>
+#include <cpu/amd/amd64_save_state.h>
+#include <cpu/amd/msr.h>
+#include <cpu/cpu.h>
+#include <cpu/x86/msr.h>
+#include <cpu/x86/smm.h>
+#include <types.h>
+
+static struct smm_relocation_params smm_reloc_params;
+
+static void fill_in_relocation_params(struct smm_relocation_params *params)
+{
+	uintptr_t tseg_base;
+	size_t tseg_size;
+
+	smm_region(&tseg_base, &tseg_size);
+
+	params->tseg_base.lo = ALIGN_DOWN(tseg_base, 128 * KiB);
+	params->tseg_base.hi = 0;
+	params->tseg_mask.lo = ALIGN_DOWN(~(tseg_size - 1), 128 * KiB);
+	params->tseg_mask.hi = ((1 << (cpu_phys_address_size() - 32)) - 1);
+
+	params->tseg_mask.lo |= SMM_TSEG_WB;
+}
+
+void get_smm_info(uintptr_t *perm_smbase, size_t *perm_smsize, size_t *smm_save_state_size)
+{
+	printk(BIOS_DEBUG, "Setting up SMI for CPU\n");
+
+	fill_in_relocation_params(&smm_reloc_params);
+
+	smm_subregion(SMM_SUBREGION_HANDLER, perm_smbase, perm_smsize);
+	*smm_save_state_size = sizeof(amd64_smm_state_save_area_t);
+}
+
+void smm_relocation_handler(int cpu, uintptr_t curr_smbase, uintptr_t staggered_smbase)
+{
+	struct smm_relocation_params *relo_params = &smm_reloc_params;
+	amd64_smm_state_save_area_t *smm_state;
+
+	wrmsr(SMM_ADDR_MSR, relo_params->tseg_base);
+	wrmsr(SMM_MASK_MSR, relo_params->tseg_mask);
+
+	smm_state = (void *)(SMM_AMD64_SAVE_STATE_OFFSET + curr_smbase);
+	smm_state->smbase = staggered_smbase;
+}
diff --git a/src/soc/amd/common/block/include/amdblocks/smm.h b/src/soc/amd/common/block/include/amdblocks/smm.h
new file mode 100644
index 0000000000..0fbef42892
--- /dev/null
+++ b/src/soc/amd/common/block/include/amdblocks/smm.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <cpu/x86/msr.h>
+#include <types.h>
+
+struct smm_relocation_params {
+	msr_t tseg_base;
+	msr_t tseg_mask;
+};
+
+void get_smm_info(uintptr_t *perm_smbase, size_t *perm_smsize, size_t *smm_save_state_size);
+void smm_relocation_handler(int cpu, uintptr_t curr_smbase, uintptr_t staggered_smbase);