--- /dev/null
+// System Management Mode support (on emulators)
+//
+// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2006 Fabrice Bellard
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "pci.h" // pci_config_writel
+#include "util.h" // wbinvd
+#include "config.h" // CONFIG_*
+#include "ioport.h" // outb
+#include "pci_ids.h" // PCI_VENDOR_ID_INTEL
+
+ASM32FLAT(
+ ".global smm_relocation_start\n"
+ ".global smm_relocation_end\n"
+ ".global smm_code_start\n"
+ ".global smm_code_end\n"
+ " .code16\n"
+
+ /* code to relocate SMBASE to 0xa0000 */
+ "smm_relocation_start:\n"
+ " mov $" __stringify(BUILD_SMM_INIT_ADDR) " + 0x7efc, %ebx\n"
+ " addr32 mov (%ebx), %al\n" /* revision ID to see if x86_64 or x86 */
+ " cmp $0x64, %al\n"
+ " je 1f\n"
+ " mov $" __stringify(BUILD_SMM_INIT_ADDR) " + 0x7ef8, %ebx\n"
+ " jmp 2f\n"
+ "1:\n"
+ " mov $" __stringify(BUILD_SMM_INIT_ADDR) " + 0x7f00, %ebx\n"
+ "2:\n"
+ " movl $" __stringify(BUILD_SMM_ADDR) " - 0x8000, %eax\n"
+ " addr32 movl %eax, (%ebx)\n"
+ /* indicate to the BIOS that the SMM code was executed */
+ " mov $0x00, %al\n"
+ " movw $" __stringify(PORT_SMI_STATUS) ", %dx\n"
+ " outb %al, %dx\n"
+ " rsm\n"
+ "smm_relocation_end:\n"
+
+ /* minimal SMM code to enable or disable ACPI */
+ "smm_code_start:\n"
+ " movw $" __stringify(PORT_SMI_CMD) ", %dx\n"
+ " inb %dx, %al\n"
+ " cmp $0xf0, %al\n"
+ " jne 1f\n"
+
+ /* ACPI disable */
+ " mov $" __stringify(PORT_ACPI_PM_BASE) " + 0x04, %dx\n" /* PMCNTRL */
+ " inw %dx, %ax\n"
+ " andw $~1, %ax\n"
+ " outw %ax, %dx\n"
+
+ " jmp 2f\n"
+
+ "1:\n"
+ " cmp $0xf1, %al\n"
+ " jne 2f\n"
+
+ /* ACPI enable */
+ " mov $" __stringify(PORT_ACPI_PM_BASE) " + 0x04, %dx\n" /* PMCNTRL */
+ " inw %dx, %ax\n"
+ " orw $1, %ax\n"
+ " outw %ax, %dx\n"
+
+ "2:\n"
+ " rsm\n"
+ "smm_code_end:\n"
+ " .code32\n"
+ );
+
+extern u8 smm_relocation_start, smm_relocation_end;
+extern u8 smm_code_start, smm_code_end;
+
+static void
+smm_save_and_copy(void)
+{
+ /* save original memory content */
+ memcpy((void *)BUILD_SMM_ADDR, (void *)BUILD_SMM_INIT_ADDR, BUILD_SMM_SIZE);
+
+ /* copy the SMM relocation code */
+ memcpy((void *)BUILD_SMM_INIT_ADDR, &smm_relocation_start,
+ &smm_relocation_end - &smm_relocation_start);
+}
+
+static void
+smm_relocate_and_restore(void)
+{
+ /* init APM status port */
+ outb(0x01, PORT_SMI_STATUS);
+
+ /* raise an SMI interrupt */
+ outb(0x00, PORT_SMI_CMD);
+
+ /* wait until SMM code executed */
+ while (inb(PORT_SMI_STATUS) != 0x00)
+ ;
+
+ /* restore original memory content */
+ memcpy((void *)BUILD_SMM_INIT_ADDR, (void *)BUILD_SMM_ADDR, BUILD_SMM_SIZE);
+
+ /* copy the SMM code */
+ memcpy((void *)BUILD_SMM_ADDR, &smm_code_start
+ , &smm_code_end - &smm_code_start);
+ wbinvd();
+}
+
+#define I440FX_SMRAM 0x72
+#define PIIX_DEVACTB 0x58
+#define PIIX_APMC_EN (1 << 25)
+
+// This code is hardcoded for PIIX4 Power Management device.
+static void piix4_apmc_smm_init(struct pci_device *pci, void *arg)
+{
+ struct pci_device *i440_pci = pci_find_device(PCI_VENDOR_ID_INTEL
+ , PCI_DEVICE_ID_INTEL_82441);
+ if (!i440_pci)
+ return;
+
+ /* check if SMM init is already done */
+ u32 value = pci_config_readl(pci->bdf, PIIX_DEVACTB);
+ if (value & PIIX_APMC_EN)
+ return;
+
+ /* enable the SMM memory window */
+ pci_config_writeb(i440_pci->bdf, I440FX_SMRAM, 0x02 | 0x48);
+
+ smm_save_and_copy();
+
+ /* enable SMI generation when writing to the APMC register */
+ pci_config_writel(pci->bdf, PIIX_DEVACTB, value | PIIX_APMC_EN);
+
+ smm_relocate_and_restore();
+
+ /* close the SMM memory window and enable normal SMM */
+ pci_config_writeb(i440_pci->bdf, I440FX_SMRAM, 0x02 | 0x08);
+}
+
+static const struct pci_device_id smm_init_tbl[] = {
+ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3,
+ piix4_apmc_smm_init),
+
+ PCI_DEVICE_END,
+};
+
+void
+smm_init(void)
+{
+ if (CONFIG_COREBOOT)
+ // SMM only supported on emulators.
+ return;
+ if (!CONFIG_USE_SMM)
+ return;
+
+ dprintf(3, "init smm\n");
+ pci_find_init_device(smm_init_tbl, NULL);
+}
