soc/amd/*/smihandler: factor out ELOG and SMMSTORE handler

This also replaces the southbridge_ prefix of the handler functions with
a handle_ prefix.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: Ib6ea1f4e2700c508a8bf72c488043e276ba4a062
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51354
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

2 files changed, 87 insertions, 0 deletions

diff --git a/src/soc/amd/common/block/cpu/smm/Makefile.inc b/src/soc/amd/common/block/cpu/smm/Makefile.inc
index 4c18d12b1d..80d06a70a5 100644
--- a/src/soc/amd/common/block/cpu/smm/Makefile.inc
+++ b/src/soc/amd/common/block/cpu/smm/Makefile.inc
@@ -7,6 +7,7 @@ postcar-y += smm_helper.c
 ramstage-y += finalize.c
 ramstage-y += smm_relocate.c
 ramstage-y += smm_helper.c
+smm-y += smi_apmc_helper.c
 smm-y += smi_handler.c
 
 endif # CONFIG_SOC_AMD_COMMON_BLOCK_SMM
diff --git a/src/soc/amd/common/block/cpu/smm/smi_apmc_helper.c b/src/soc/amd/common/block/cpu/smm/smi_apmc_helper.c
new file mode 100644
index 0000000000..576c9180c8
--- /dev/null
+++ b/src/soc/amd/common/block/cpu/smm/smi_apmc_helper.c
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <amdblocks/smm.h>
+#include <cpu/amd/amd64_save_state.h>
+#include <cpu/x86/smm.h>
+#include <elog.h>
+#include <smmstore.h>
+#include <types.h>
+
+/* bits in smm_io_trap   */
+#define SMM_IO_TRAP_PORT_OFFSET		16
+#define SMM_IO_TRAP_PORT_ADDRESS_MASK	0xffff
+#define SMM_IO_TRAP_RW			(1 << 0)
+#define SMM_IO_TRAP_VALID		(1 << 1)
+
+static inline u16 get_io_address(u32 info)
+{
+	return ((info >> SMM_IO_TRAP_PORT_OFFSET) &
+		SMM_IO_TRAP_PORT_ADDRESS_MASK);
+}
+
+static void *find_save_state(int cmd)
+{
+	unsigned int core;
+	amd64_smm_state_save_area_t *state;
+	u32 smm_io_trap;
+	u8 reg_al;
+
+	/* Check all nodes looking for the one that issued the IO */
+	for (core = 0; core < CONFIG_MAX_CPUS; core++) {
+		state = smm_get_save_state(core);
+		smm_io_trap = state->smm_io_trap_offset;
+		/* Check for Valid IO Trap Word (bit1==1) */
+		if (!(smm_io_trap & SMM_IO_TRAP_VALID))
+			continue;
+		/* Make sure it was a write (bit0==0) */
+		if (smm_io_trap & SMM_IO_TRAP_RW)
+			continue;
+		/* Check for APMC IO port */
+		if (pm_acpi_smi_cmd_port() != get_io_address(smm_io_trap))
+			continue;
+		/* Check AL against the requested command */
+		reg_al = state->rax;
+		if (reg_al == cmd)
+			return state;
+	}
+	return NULL;
+}
+
+void handle_smi_gsmi(void)
+{
+	u8 sub_command;
+	amd64_smm_state_save_area_t *io_smi;
+	u32 reg_ebx;
+
+	io_smi = find_save_state(APM_CNT_ELOG_GSMI);
+	if (!io_smi)
+		return;
+	/* Command and return value in EAX */
+	sub_command = (io_smi->rax >> 8) & 0xff;
+
+	/* Parameter buffer in EBX */
+	reg_ebx = io_smi->rbx;
+
+	/* drivers/elog/gsmi.c */
+	io_smi->rax = gsmi_exec(sub_command, &reg_ebx);
+}
+
+void handle_smi_store(void)
+{
+	u8 sub_command;
+	amd64_smm_state_save_area_t *io_smi;
+	u32 reg_ebx;
+
+	io_smi = find_save_state(APM_CNT_SMMSTORE);
+	if (!io_smi)
+		return;
+	/* Command and return value in EAX */
+	sub_command = (io_smi->rax >> 8) & 0xff;
+
+	/* Parameter buffer in EBX */
+	reg_ebx = io_smi->rbx;
+
+	/* drivers/smmstore/smi.c */
+	io_smi->rax = smmstore_exec(sub_command, (void *)reg_ebx);
+}