baytrail: SMM support

Initialize SMM on all CPUs by relocating the SMM region
and setting SMRR on all the cores. Additionally SMI
is enabled in the south cluster.

BUG=chrome-os-partner:22862
BRANCH=None
TEST=Built and booted rambi. Tested with DEBUG_SMI and noted
     power button turns off board while in firmware.

Change-Id: I92e3460572feeb67d4a3d4d26af5f0ecaf7d3dd5
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/173983
Reviewed-on: http://review.coreboot.org/4892
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/src/soc/intel/baytrail/smm.c b/src/soc/intel/baytrail/smm.c
new file mode 100644
index 0000000000..124f93be59
--- /dev/null
+++ b/src/soc/intel/baytrail/smm.c
@@ -0,0 +1,91 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <device/device.h>
+#include <device/pci.h>
+#include <console/console.h>
+#include <arch/io.h>
+#include <cpu/cpu.h>
+#include <cpu/x86/smm.h>
+#include <string.h>
+
+#include <baytrail/pmc.h>
+#include <baytrail/smm.h>
+
+void southcluster_smm_clear_state(void)
+{
+	uint32_t smi_en;
+
+	/* Log events from chipset before clearing */
+	southcluster_log_state();
+
+	printk(BIOS_DEBUG, "Initializing Southbridge SMI...");
+	printk(BIOS_SPEW, " pmbase = 0x%04x\n", get_pmbase());
+
+	smi_en = inl(get_pmbase() + SMI_EN);
+	if (smi_en & APMC_EN) {
+		printk(BIOS_INFO, "SMI# handler already enabled?\n");
+		return;
+	}
+
+	/* Dump and clear status registers */
+	clear_smi_status();
+	clear_pm1_status();
+	clear_tco_status();
+	clear_gpe_status();
+}
+
+void southcluster_smm_enable_smi(void)
+{
+	printk(BIOS_DEBUG, "Enabling SMIs.\n");
+	/* Configure events */
+	enable_pm1(PWRBTN_EN | GBL_EN);
+	disable_gpe(PME_B0_EN);
+
+	/* Enable SMI generation:
+	 *  - on TCO events
+	 *  - on APMC writes (io 0xb2)
+	 *  - on writes to SLP_EN (sleep states)
+	 *  - on writes to GBL_RLS (bios commands)
+	 * No SMIs:
+	 *  - on microcontroller writes (io 0x62/0x66)
+	 */
+	enable_smi(TCO_EN | APMC_EN | SLP_SMI_EN | GBL_SMI_EN | EOS);
+}
+
+void smm_setup_structures(void *gnvs, void *tcg, void *smi1)
+{
+	/*
+	 * Issue SMI to set the gnvs pointer in SMM.
+	 * tcg and smi1 are unused.
+	 *
+	 * EAX = APM_CNT_GNVS_UPDATE
+	 * EBX = gnvs pointer
+	 * EDX = APM_CNT
+	 */
+	asm volatile (
+		"outb %%al, %%dx\n\t"
+		: /* ignore result */
+		: "a" (APM_CNT_GNVS_UPDATE),
+		  "b" ((uint32_t)gnvs),
+		  "d" (APM_CNT)
+	);
+}