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-rw-r--r--src/soc/intel/fsp_baytrail/acpi.c574
1 files changed, 574 insertions, 0 deletions
diff --git a/src/soc/intel/fsp_baytrail/acpi.c b/src/soc/intel/fsp_baytrail/acpi.c
new file mode 100644
index 0000000000..dece178ba5
--- /dev/null
+++ b/src/soc/intel/fsp_baytrail/acpi.c
@@ -0,0 +1,574 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2009 coresystems GmbH
+ * Copyright (C) 2011 The Chromium OS Authors. All rights reserved.
+ * Copyright (C) 2013-2014 Sage Electronic Engineering, LLC.
+ *
+ * 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 <types.h>
+#include <console/console.h>
+#include <arch/acpi.h>
+#include <arch/acpigen.h>
+#include <arch/cpu.h>
+#include <cpu/x86/msr.h>
+#include <cpu/intel/speedstep.h>
+#include <cpu/intel/turbo.h>
+#include <arch/smp/mpspec.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <baytrail/baytrail.h>
+#include <device/pci_ids.h>
+#include <baytrail/pci_devs.h>
+#include <baytrail/acpi.h>
+#include <string.h>
+#include <baytrail/iomap.h>
+#include <baytrail/lpc.h>
+#include <baytrail/pci_devs.h>
+#include <baytrail/pmc.h>
+#include <baytrail/irq.h>
+#include <baytrail/iosf.h>
+#include <arch/io.h>
+#include <baytrail/msr.h>
+#include <baytrail/pattrs.h>
+#include <baytrail/pmc.h>
+#include <cbmem.h>
+
+#include "chip.h"
+
+#define MWAIT_RES(state, sub_state) \
+ { \
+ .addrl = (((state) << 4) | (sub_state)), \
+ .space_id = ACPI_ADDRESS_SPACE_FIXED, \
+ .bit_width = ACPI_FFIXEDHW_VENDOR_INTEL, \
+ .bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT, \
+ .access_size = ACPI_FFIXEDHW_FLAG_HW_COORD, \
+ }
+
+/* C-state map without S0ix */
+static acpi_cstate_t cstate_map[] = {
+ {
+ /* C1 */
+ .ctype = 1, /* ACPI C1 */
+ .latency = 1,
+ .power = 1000,
+ .resource = MWAIT_RES(0, 0),
+ },
+ {
+ /* C6NS with no L2 shrink */
+ /* NOTE: this substate is above CPUID limit */
+ .ctype = 2, /* ACPI C2 */
+ .latency = 500,
+ .power = 10,
+ .resource = MWAIT_RES(5, 1),
+ },
+ {
+ /* C6FS with full L2 shrink */
+ .ctype = 3, /* ACPI C3 */
+ .latency = 1500, /* 1.5ms worst case */
+ .power = 10,
+ .resource = MWAIT_RES(5, 2),
+ }
+};
+
+void acpi_init_gnvs(global_nvs_t *gnvs)
+{
+ /* CPU core count */
+ gnvs->pcnt = dev_count_cpu();
+
+ /* Top of Low Memory (start of resource allocation) */
+ gnvs->tolm = nc_read_top_of_low_memory();
+
+#if IS_ENABLED(CONFIG_CONSOLE_CBMEM)
+ /* Update the mem console pointer. */
+ gnvs->cbmc = (u32)cbmem_find(CBMEM_ID_CONSOLE);
+#endif
+}
+
+static int acpi_sci_irq(void)
+{
+ const unsigned long actl = ILB_BASE_ADDRESS + ACTL;
+ int scis;
+ static int sci_irq;
+
+ if (sci_irq)
+ return sci_irq;
+
+ /* Determine how SCI is routed. */
+ scis = read32(actl) & SCIS_MASK;
+ switch (scis) {
+ case SCIS_IRQ9:
+ case SCIS_IRQ10:
+ case SCIS_IRQ11:
+ sci_irq = scis - SCIS_IRQ9 + 9;
+ break;
+ case SCIS_IRQ20:
+ case SCIS_IRQ21:
+ case SCIS_IRQ22:
+ case SCIS_IRQ23:
+ sci_irq = scis - SCIS_IRQ20 + 20;
+ break;
+ default:
+ printk(BIOS_DEBUG, "Invalid SCI route! Defaulting to IRQ9.\n");
+ sci_irq = 9;
+ break;
+ }
+
+ printk(BIOS_DEBUG, "SCI is IRQ%d\n", sci_irq);
+ return sci_irq;
+}
+
+void acpi_create_intel_hpet(acpi_hpet_t * hpet)
+{
+ acpi_header_t *header = &(hpet->header);
+ acpi_addr_t *addr = &(hpet->addr);
+
+ memset((void *) hpet, 0, sizeof(acpi_hpet_t));
+
+ /* fill out header fields */
+ memcpy(header->signature, "HPET", 4);
+ memcpy(header->oem_id, OEM_ID, 6);
+ memcpy(header->oem_table_id, ACPI_TABLE_CREATOR, 8);
+ memcpy(header->asl_compiler_id, ASLC, 4);
+
+ header->length = sizeof(acpi_hpet_t);
+ header->revision = 1;
+
+ /* fill out HPET address */
+ addr->space_id = 0; /* Memory */
+ addr->bit_width = 64;
+ addr->bit_offset = 0;
+ addr->addrl = (unsigned long long)HPET_BASE_ADDRESS & 0xffffffff;
+ addr->addrh = (unsigned long long)HPET_BASE_ADDRESS >> 32;
+
+ hpet->id = 0x8086a201; /* Intel */
+ hpet->number = 0x00;
+ hpet->min_tick = 0x0080;
+
+ header->checksum =
+ acpi_checksum((void *) hpet, sizeof(acpi_hpet_t));
+}
+
+unsigned long acpi_fill_mcfg(unsigned long current)
+{
+ current += acpi_create_mcfg_mmconfig((acpi_mcfg_mmconfig_t *)current,
+ MCFG_BASE_ADDRESS, 0, 0, 255);
+ return current;
+}
+
+/**
+ * Fill in the fadt with generic values that can be overridden later.
+ */
+
+typedef struct soc_intel_fsp_baytrail_config config_t;
+
+void acpi_fill_in_fadt(acpi_fadt_t * fadt, acpi_facs_t * facs, void *dsdt)
+{
+ acpi_header_t *header = &(fadt->header);
+ struct device *lpcdev = dev_find_slot(FADT_SOC_LPC_DEV);
+ u16 pmbase = pci_read_config16(lpcdev, ABASE) & 0xfff0;
+ config_t *config = lpcdev->chip_info;
+
+ memset((void *) fadt, 0, sizeof(acpi_fadt_t));
+
+ /*
+ * Reference section 5.2.9 Fixed ACPI Description Table (FADT)
+ * in the ACPI 3.0b specification.
+ */
+
+ /* FADT Header Structure */
+ memcpy(header->signature, "FACP", 4);
+ header->length = sizeof(acpi_fadt_t);
+ header->revision = ACPI_FADT_REV_ACPI_3_0;
+ memcpy(header->oem_id, OEM_ID, 6);
+ memcpy(header->oem_table_id, ACPI_TABLE_CREATOR, 8);
+ memcpy(header->asl_compiler_id, ASLC, 4);
+ header->asl_compiler_revision = 1;
+
+ /* ACPI Pointers */
+ fadt->firmware_ctrl = (unsigned long) facs;
+ fadt->dsdt = (unsigned long) dsdt;
+
+ fadt->model = 0; /* reserved, should be 0 ACPI 3.0 */
+ fadt->preferred_pm_profile = config->fadt_pm_profile; /* unknown is default */
+
+ /* System Management */
+ fadt->sci_int = acpi_sci_irq();
+#if IS_ENABLED(CONFIG_BAYTRAIL_SMM)
+ fadt->smi_cmd = APM_CNT;
+ fadt->acpi_enable = APM_CNT_ACPI_ENABLE;
+ fadt->acpi_disable = APM_CNT_ACPI_DISABLE;
+#else
+ fadt->smi_cmd = 0x00; /* disable SMM */
+ fadt->acpi_enable = 0x00; /* unused if SMI_CMD = 0 */
+ fadt->acpi_disable = 0x00; /* unused if SMI_CMD = 0 */
+
+ /* Enable ACPI */
+ outl(inl(pmbase + 4) | 0x01, pmbase + 4);
+#endif
+
+ /* Power Control */
+ fadt->s4bios_req = 0x00;
+ fadt->pstate_cnt = 0x00;
+
+ /* Control Registers - Base Address */
+ fadt->pm1a_evt_blk = pmbase + PM1_STS;
+ fadt->pm1b_evt_blk = 0x00; /* Not Used */
+ fadt->pm1a_cnt_blk = pmbase + PM1_CNT;
+ fadt->pm1b_cnt_blk = 0x00; /* Not Used */
+ fadt->pm2_cnt_blk = pmbase + PM2A_CNT_BLK;
+ fadt->pm_tmr_blk = pmbase + PM1_TMR;
+ fadt->gpe0_blk = pmbase + GPE0_STS;
+ fadt->gpe1_blk = 0x00; /* Not Used */
+
+ /* Control Registers - Length */
+ fadt->pm1_evt_len = 4; /* 32 bits */
+ fadt->pm1_cnt_len = 2; /* 32 bit register, 16 bits used */
+ fadt->pm2_cnt_len = 1; /* 8 bits */
+ fadt->pm_tmr_len = 4; /* 32 bits */
+ fadt->gpe0_blk_len = 8; /* 64 bits */
+ fadt->gpe1_blk_len = 0;
+ fadt->gpe1_base = 0;
+ fadt->cst_cnt = 0;
+ fadt->p_lvl2_lat = ACPI_FADT_C2_NOT_SUPPORTED;
+ fadt->p_lvl3_lat = ACPI_FADT_C3_NOT_SUPPORTED;
+ fadt->flush_size = 0; /* set to 0 if WBINVD is 1 in flags */
+ fadt->flush_stride = 0; /* set to 0 if WBINVD is 1 in flags */
+ fadt->duty_offset = 1;
+ fadt->duty_width = 0;
+
+ /* RTC Registers */
+ fadt->day_alrm = 0x0D;
+ fadt->mon_alrm = 0x00;
+ fadt->century = 0x00;
+ fadt->iapc_boot_arch = config->fadt_boot_arch; /* legacy free default */
+
+ fadt->flags = ACPI_FADT_WBINVD | ACPI_FADT_C1_SUPPORTED |
+ ACPI_FADT_C2_MP_SUPPORTED | ACPI_FADT_SLEEP_BUTTON |
+ ACPI_FADT_RESET_REGISTER | ACPI_FADT_SLEEP_TYPE |
+ ACPI_FADT_S4_RTC_WAKE | ACPI_FADT_PLATFORM_CLOCK;
+
+ /* Reset Register */
+ fadt->reset_reg.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->reset_reg.bit_width = 8;
+ fadt->reset_reg.bit_offset = 0;
+ fadt->reset_reg.access_size = ACPI_ACCESS_SIZE_BYTE_ACCESS;
+ fadt->reset_reg.addrl = 0xCF9;
+ fadt->reset_reg.addrh = 0x00;
+ fadt->reset_value = 6;
+
+ /* Reserved Bits */
+ fadt->res3 = 0x00; /* reserved, MUST be 0 ACPI 3.0 */
+ fadt->res4 = 0x00; /* reserved, MUST be 0 ACPI 3.0 */
+ fadt->res5 = 0x00; /* reserved, MUST be 0 ACPI 3.0 */
+
+ /* Extended ACPI Pointers */
+ fadt->x_firmware_ctl_l = (unsigned long)facs;
+ fadt->x_firmware_ctl_h = 0x00;
+ fadt->x_dsdt_l = (unsigned long)dsdt;
+ fadt->x_dsdt_h = 0x00;
+
+ /* PM1 Status & PM1 Enable */
+ fadt->x_pm1a_evt_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm1a_evt_blk.bit_width = 32;
+ fadt->x_pm1a_evt_blk.bit_offset = 0;
+ fadt->x_pm1a_evt_blk.access_size = ACPI_ACCESS_SIZE_DWORD_ACCESS;
+ fadt->x_pm1a_evt_blk.addrl = fadt->pm1a_evt_blk;
+ fadt->x_pm1a_evt_blk.addrh = 0x00;
+
+ fadt->x_pm1b_evt_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm1b_evt_blk.bit_width = 0;
+ fadt->x_pm1b_evt_blk.bit_offset = 0;
+ fadt->x_pm1b_evt_blk.access_size = 0;
+ fadt->x_pm1b_evt_blk.addrl = fadt->pm1b_evt_blk;
+ fadt->x_pm1b_evt_blk.addrh = 0x00;
+
+ /* PM1 Control Registers */
+ fadt->x_pm1a_cnt_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm1a_cnt_blk.bit_width = 16;
+ fadt->x_pm1a_cnt_blk.bit_offset = 0;
+ fadt->x_pm1a_cnt_blk.access_size = ACPI_ACCESS_SIZE_WORD_ACCESS;
+ fadt->x_pm1a_cnt_blk.addrl = fadt->pm1a_cnt_blk;
+ fadt->x_pm1a_cnt_blk.addrh = 0x00;
+
+ fadt->x_pm1b_cnt_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm1b_cnt_blk.bit_width = 0;
+ fadt->x_pm1b_cnt_blk.bit_offset = 0;
+ fadt->x_pm1b_cnt_blk.access_size = 0;
+ fadt->x_pm1b_cnt_blk.addrl = fadt->pm1b_cnt_blk;
+ fadt->x_pm1b_cnt_blk.addrh = 0x00;
+
+ /* PM2 Control Registers */
+ fadt->x_pm2_cnt_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm2_cnt_blk.bit_width = 8;
+ fadt->x_pm2_cnt_blk.bit_offset = 0;
+ fadt->x_pm2_cnt_blk.access_size = ACPI_ACCESS_SIZE_BYTE_ACCESS;
+ fadt->x_pm2_cnt_blk.addrl = fadt->pm2_cnt_blk;
+ fadt->x_pm2_cnt_blk.addrh = 0x00;
+
+ /* PM1 Timer Register */
+ fadt->x_pm_tmr_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_pm_tmr_blk.bit_width = 32;
+ fadt->x_pm_tmr_blk.bit_offset = 0;
+ fadt->x_pm_tmr_blk.access_size = ACPI_ACCESS_SIZE_DWORD_ACCESS;
+ fadt->x_pm_tmr_blk.addrl = fadt->pm_tmr_blk;
+ fadt->x_pm_tmr_blk.addrh = 0x00;
+
+ /* General-Purpose Event Registers */
+ fadt->x_gpe0_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_gpe0_blk.bit_width = 64; /* EventStatus + EventEnable */
+ fadt->x_gpe0_blk.bit_offset = 0;
+ fadt->x_gpe0_blk.access_size = ACPI_ACCESS_SIZE_DWORD_ACCESS;
+ fadt->x_gpe0_blk.addrl = fadt->gpe0_blk;
+ fadt->x_gpe0_blk.addrh = 0x00;
+
+ fadt->x_gpe1_blk.space_id = ACPI_ADDRESS_SPACE_IO;
+ fadt->x_gpe1_blk.bit_width = 0;
+ fadt->x_gpe1_blk.bit_offset = 0;
+ fadt->x_gpe1_blk.access_size = 0;
+ fadt->x_gpe1_blk.addrl = fadt->gpe1_blk;
+ fadt->x_gpe1_blk.addrh = 0x00;
+
+ header->checksum =
+ acpi_checksum((void *) fadt, sizeof(acpi_fadt_t));
+}
+static acpi_tstate_t baytrail_tss_table[] = {
+ { 100, 1000, 0, 0x00, 0 },
+ { 88, 875, 0, 0x1e, 0 },
+ { 75, 750, 0, 0x1c, 0 },
+ { 63, 625, 0, 0x1a, 0 },
+ { 50, 500, 0, 0x18, 0 },
+ { 38, 375, 0, 0x16, 0 },
+ { 25, 250, 0, 0x14, 0 },
+ { 13, 125, 0, 0x12, 0 },
+};
+
+static int generate_T_state_entries(int core, int cores_per_package)
+{
+ int len;
+
+ /* Indicate SW_ALL coordination for T-states */
+ len = acpigen_write_TSD_package(core, cores_per_package, SW_ALL);
+
+ /* Indicate FFixedHW so OS will use MSR */
+ len += acpigen_write_empty_PTC();
+
+ /* Set NVS controlled T-state limit */
+ len += acpigen_write_TPC("\\TLVL");
+
+ /* Write TSS table for MSR access */
+ len += acpigen_write_TSS_package(
+ ARRAY_SIZE(baytrail_tss_table), baytrail_tss_table);
+
+ return len;
+}
+
+static int calculate_power(int tdp, int p1_ratio, int ratio)
+{
+ u32 m;
+ u32 power;
+
+ /*
+ * M = ((1.1 - ((p1_ratio - ratio) * 0.00625)) / 1.1) ^ 2
+ *
+ * Power = (ratio / p1_ratio) * m * tdp
+ */
+
+ m = (110000 - ((p1_ratio - ratio) * 625)) / 11;
+ m = (m * m) / 1000;
+
+ power = ((ratio * 100000 / p1_ratio) / 100);
+ power *= (m / 100) * (tdp / 1000);
+ power /= 1000;
+
+ return (int)power;
+}
+
+static int generate_P_state_entries(int core, int cores_per_package)
+{
+ int len, len_pss;
+ int ratio_min, ratio_max, ratio_turbo, ratio_step, ratio_range_2;
+ int coord_type, power_max, power_unit, num_entries;
+ int ratio, power, clock, clock_max;
+ int vid, vid_turbo, vid_min, vid_max, vid_range_2;
+ u32 control_status;
+ const struct pattrs *pattrs = pattrs_get();
+ msr_t msr;
+
+ /* Inputs from CPU attributes */
+ ratio_max = pattrs->iacore_ratios[IACORE_MAX];
+ ratio_min = pattrs->iacore_ratios[IACORE_LFM];
+ vid_max = pattrs->iacore_vids[IACORE_MAX];
+ vid_min = pattrs->iacore_vids[IACORE_LFM];
+
+ /* Hardware coordination of P-states */
+ coord_type = HW_ALL;
+
+ /* Max Non-Turbo Frequency */
+ clock_max = (ratio_max * pattrs->bclk_khz) / 1000;
+
+ /* Calculate CPU TDP in mW */
+ msr = rdmsr(MSR_PKG_POWER_SKU_UNIT);
+ power_unit = 1 << (msr.lo & 0xf);
+ msr = rdmsr(MSR_PKG_POWER_LIMIT);
+ power_max = ((msr.lo & 0x7fff) / power_unit) * 1000;
+
+ /* Write _PCT indicating use of FFixedHW */
+ len = acpigen_write_empty_PCT();
+
+ /* Write _PPC with NVS specified limit on supported P-state */
+ len += acpigen_write_PPC_NVS();
+
+ /* Write PSD indicating configured coordination type */
+ len += acpigen_write_PSD_package(core, 1, coord_type);
+
+ /* Add P-state entries in _PSS table */
+ len += acpigen_write_name("_PSS");
+
+ /* Determine ratio points */
+ ratio_step = 1;
+ num_entries = (ratio_max - ratio_min) / ratio_step;
+ while (num_entries > 15) { /* ACPI max is 15 ratios */
+ ratio_step <<= 1;
+ num_entries >>= 1;
+ }
+
+ /* P[T] is Turbo state if enabled */
+ if (get_turbo_state() == TURBO_ENABLED) {
+ /* _PSS package count including Turbo */
+ len_pss = acpigen_write_package(num_entries + 2);
+
+ ratio_turbo = pattrs->iacore_ratios[IACORE_TURBO];
+ vid_turbo = pattrs->iacore_vids[IACORE_TURBO];
+ control_status = (ratio_turbo << 8) | vid_turbo;
+
+ /* Add entry for Turbo ratio */
+ len_pss += acpigen_write_PSS_package(
+ clock_max + 1, /*MHz*/
+ power_max, /*mW*/
+ 10, /*lat1*/
+ 10, /*lat2*/
+ control_status, /*control*/
+ control_status); /*status*/
+ } else {
+ /* _PSS package count without Turbo */
+ len_pss = acpigen_write_package(num_entries + 1);
+ ratio_turbo = ratio_max;
+ vid_turbo = vid_max;
+ }
+
+ /* First regular entry is max non-turbo ratio */
+ control_status = (ratio_max << 8) | vid_max;
+ len_pss += acpigen_write_PSS_package(
+ clock_max, /*MHz*/
+ power_max, /*mW*/
+ 10, /*lat1*/
+ 10, /*lat2*/
+ control_status, /*control */
+ control_status); /*status*/
+
+ /* Set up ratio and vid ranges for VID calculation */
+ ratio_range_2 = (ratio_turbo - ratio_min) * 2;
+ vid_range_2 = (vid_turbo - vid_min) * 2;
+
+ /* Generate the remaining entries */
+ for (ratio = ratio_min + ((num_entries - 1) * ratio_step);
+ ratio >= ratio_min; ratio -= ratio_step) {
+
+ /* Calculate VID for this ratio */
+ vid = ((ratio - ratio_min) * vid_range_2) /
+ ratio_range_2 + vid_min;
+ /* Round up if remainder */
+ if (((ratio - ratio_min) * vid_range_2) % ratio_range_2)
+ vid++;
+
+ /* Calculate power at this ratio */
+ power = calculate_power(power_max, ratio_max, ratio);
+ clock = (ratio * pattrs->bclk_khz) / 1000;
+ control_status = (ratio << 8) | (vid & 0xff);
+
+ len_pss += acpigen_write_PSS_package(
+ clock, /*MHz*/
+ power, /*mW*/
+ 10, /*lat1*/
+ 10, /*lat2*/
+ control_status, /*control*/
+ control_status); /*status*/
+ }
+
+ /* Fix package length */
+ len_pss--;
+ acpigen_patch_len(len_pss);
+
+ return len + len_pss;
+}
+
+void generate_cpu_entries(void)
+{
+ int len_pr, core;
+ int pcontrol_blk = get_pmbase(), plen = 6;
+ const struct pattrs *pattrs = pattrs_get();
+
+ for (core=0; core<pattrs->num_cpus; core++) {
+ if (core > 0) {
+ pcontrol_blk = 0;
+ plen = 0;
+ }
+
+ /* Generate processor \_PR.CPUx */
+ len_pr = acpigen_write_processor(
+ core, pcontrol_blk, plen);
+
+ /* Generate P-state tables */
+ len_pr += generate_P_state_entries(
+ core, pattrs->num_cpus);
+
+ /* Generate C-state tables */
+ len_pr += acpigen_write_CST_package(
+ cstate_map, ARRAY_SIZE(cstate_map));
+
+ /* Generate T-state tables */
+ len_pr += generate_T_state_entries(
+ core, pattrs->num_cpus);
+
+ len_pr--;
+ acpigen_patch_len(len_pr);
+ }
+}
+
+unsigned long acpi_madt_irq_overrides(unsigned long current)
+{
+ int sci_irq = acpi_sci_irq();
+ acpi_madt_irqoverride_t *irqovr;
+ uint16_t sci_flags = MP_IRQ_TRIGGER_LEVEL;
+
+ /* INT_SRC_OVR */
+ irqovr = (void *)current;
+ current += acpi_create_madt_irqoverride(irqovr, 0, 0, 2, 0);
+
+ if (sci_irq >= 20)
+ sci_flags |= MP_IRQ_POLARITY_LOW;
+ else
+ sci_flags |= MP_IRQ_POLARITY_HIGH;
+
+ irqovr = (void *)current;
+ current += acpi_create_madt_irqoverride(irqovr, 0, sci_irq, sci_irq,
+ sci_flags);
+
+ return current;
+}