smihandler.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <delay.h>
#include <types.h>
#include <arch/io.h>
#include <device/mmio.h>
#include <device/pci_ops.h>
#include <console/console.h>
#include <cpu/x86/cache.h>
#include <device/pci_def.h>
#include <cpu/x86/smm.h>
#include <cpu/intel/em64t101_save_state.h>
#include <spi-generic.h>
#include <elog.h>
#include <halt.h>
#include <option.h>
#include <soc/lpc.h>
#include <soc/nvs.h>
#include <soc/pci_devs.h>
#include <soc/pm.h>
#include <soc/rcba.h>
#include <soc/xhci.h>
#include <drivers/intel/gma/i915_reg.h>
#include <smmstore.h>
 
int southbridge_io_trap_handler(int smif)
{
        switch (smif) {
        case 0x32:
                printk(BIOS_DEBUG, "OS Init\n");
                /* gnvs->smif:
                 *  On success, the IO Trap Handler returns 0
                 *  On failure, the IO Trap Handler returns a value != 0
                 */
                gnvs->smif = 0;
                return 1; /* IO trap handled */
        }
 
        /* Not handled */
        return 0;
}
 
/**
 * @brief Set the EOS bit
 */
void southbridge_smi_set_eos(void)
{
        enable_smi(EOS);
}
 
static void busmaster_disable_on_bus(int bus)
{
        int slot, func;
        unsigned int val;
        unsigned char hdr;
 
        for (slot = 0; slot < 0x20; slot++) {
                for (func = 0; func < 8; func++) {
                        pci_devfn_t dev = PCI_DEV(bus, slot, func);
 
                        val = pci_read_config32(dev, PCI_VENDOR_ID);
 
                        if (val == 0xffffffff || val == 0x00000000 ||
                            val == 0x0000ffff || val == 0xffff0000)
                                continue;
 
                        /* Disable Bus Mastering for this one device */
                        pci_and_config16(dev, PCI_COMMAND, ~PCI_COMMAND_MASTER);
 
                        /* If this is a bridge, then follow it. */
                        hdr = pci_read_config8(dev, PCI_HEADER_TYPE);
                        hdr &= 0x7f;
                        if (hdr == PCI_HEADER_TYPE_BRIDGE ||
                            hdr == PCI_HEADER_TYPE_CARDBUS) {
                                unsigned int buses;
                                buses = pci_read_config32(dev, PCI_PRIMARY_BUS);
                                busmaster_disable_on_bus((buses >> 8) & 0xff);
                        }
                }
        }
}
 
/*
 * Turn off the backlight if it is on, and wait for the specified
 * backlight off delay.  This will allow panel power timings to meet
 * spec and prevent brief garbage on the screen when turned off
 * during firmware with power button triggered SMI.
 */
static void backlight_off(void)
{
        void *reg_base;
        uint32_t pp_ctrl;
        uint32_t bl_off_delay;
 
        reg_base = (void *)((uintptr_t)pci_read_config32(SA_DEV_IGD,
                PCI_BASE_ADDRESS_0) & ~0xf);
 
        /* Validate pointer before using it */
        if (smm_points_to_smram(reg_base, PCH_PP_OFF_DELAYS + sizeof(uint32_t)))
                return;
 
        /* Check if backlight is enabled */
        pp_ctrl = read32(reg_base + PCH_PP_CONTROL);
        if (!(pp_ctrl & EDP_BLC_ENABLE))
                return;
 
        /* Enable writes to this register */
        pp_ctrl &= ~PANEL_UNLOCK_MASK;
        pp_ctrl |= PANEL_UNLOCK_REGS;
 
        /* Turn off backlight */
        pp_ctrl &= ~EDP_BLC_ENABLE;
 
        write32(reg_base + PCH_PP_CONTROL, pp_ctrl);
        read32(reg_base + PCH_PP_CONTROL);
 
        /* Read backlight off delay in 100us units */
        bl_off_delay = read32(reg_base + PCH_PP_OFF_DELAYS);
        bl_off_delay &= PANEL_LIGHT_OFF_DELAY_MASK;
        bl_off_delay *= 100;
 
        /* Wait for backlight to turn off */
        udelay(bl_off_delay);
 
        printk(BIOS_INFO, "Backlight turned off\n");
}
 
static int power_on_after_fail(void)
{
        /* save and recover RTC port values */
        u8 tmp70, tmp72;
        tmp70 = inb(0x70);
        tmp72 = inb(0x72);
        const unsigned int s5pwr = get_uint_option("power_on_after_fail",
                                         CONFIG_MAINBOARD_POWER_FAILURE_STATE);
        outb(tmp70, 0x70);
        outb(tmp72, 0x72);
 
        /* For "KEEP", switch to "OFF" - KEEP is software emulated. */
        return (s5pwr == MAINBOARD_POWER_ON);
}
 
static void southbridge_smi_sleep(void)
{
        u32 reg32;
        u8 slp_typ;
        u16 pmbase = get_pmbase();
 
        /* First, disable further SMIs */
        disable_smi(SLP_SMI_EN);
 
        /* Figure out SLP_TYP */
        reg32 = inl(pmbase + PM1_CNT);
        printk(BIOS_SPEW, "SMI#: SLP = 0x%08x\n", reg32);
        slp_typ = acpi_sleep_from_pm1(reg32);
 
        /* Do any mainboard sleep handling */
        mainboard_smi_sleep(slp_typ);
 
        /* USB sleep preparations */
        usb_xhci_sleep_prepare(PCH_DEV_XHCI, slp_typ);
 
        /* Log S3, S4, and S5 entry */
        if (slp_typ >= ACPI_S3)
                elog_gsmi_add_event_byte(ELOG_TYPE_ACPI_ENTER, slp_typ);
 
        /* Clear pending GPE events */
        clear_gpe_status();
 
        /* Next, do the deed.
         */
 
        switch (slp_typ) {
        case ACPI_S0:
                printk(BIOS_DEBUG, "SMI#: Entering S0 (On)\n");
                break;
        case ACPI_S1:
                printk(BIOS_DEBUG, "SMI#: Entering S1 (Assert STPCLK#)\n");
                break;
        case ACPI_S3:
                printk(BIOS_DEBUG, "SMI#: Entering S3 (Suspend-To-RAM)\n");
 
                /* Invalidate the cache before going to S3 */
                wbinvd();
                break;
        case ACPI_S4:
                printk(BIOS_DEBUG, "SMI#: Entering S4 (Suspend-To-Disk)\n");
                break;
        case ACPI_S5:
                printk(BIOS_DEBUG, "SMI#: Entering S5 (Soft Power off)\n");
 
                /* Turn off backlight if needed */
                backlight_off();
 
                /* Disable all GPE */
                disable_all_gpe();
 
                /* Always set the flag in case CMOS was changed on runtime. */
                if (power_on_after_fail())
                        pci_and_config8(PCH_DEV_LPC, GEN_PMCON_3, ~1);
                else
                        pci_or_config8(PCH_DEV_LPC, GEN_PMCON_3, 1);
 
                /* also iterates over all bridges on bus 0 */
                busmaster_disable_on_bus(0);
                break;
        default:
                printk(BIOS_DEBUG, "SMI#: ERROR: SLP_TYP reserved\n");
                break;
        }
 
        /*
         * Write back to the SLP register to cause the originally intended
         * event again. We need to set BIT13 (SLP_EN) though to make the
         * sleep happen.
         */
        enable_pm1_control(SLP_EN);
 
        /* Make sure to stop executing code here for S3/S4/S5 */
        if (slp_typ >= ACPI_S3)
                halt();
 
        /*
         * In most sleep states, the code flow of this function ends at
         * the line above. However, if we entered sleep state S1 and wake
         * up again, we will continue to execute code in this function.
         */
        reg32 = inl(pmbase + PM1_CNT);
        if (reg32 & SCI_EN) {
                /* The OS is not an ACPI OS, so we set the state to S0 */
                disable_pm1_control(SLP_EN | SLP_TYP);
        }
}
 
/*
 * Look for Synchronous IO SMI and use save state from that
 * core in case we are not running on the same core that
 * initiated the IO transaction.
 */
static em64t101_smm_state_save_area_t *smi_apmc_find_state_save(u8 cmd)
{
        em64t101_smm_state_save_area_t *state;
        int node;
 
        /* Check all nodes looking for the one that issued the IO */
        for (node = 0; node < CONFIG_MAX_CPUS; node++) {
                state = smm_get_save_state(node);
 
                /* Check for Synchronous IO (bit0 == 1) */
                if (!(state->io_misc_info & (1 << 0)))
                        continue;
 
                /* Make sure it was a write (bit4 == 0) */
                if (state->io_misc_info & (1 << 4))
                        continue;
 
                /* Check for APMC IO port */
                if (((state->io_misc_info >> 16) & 0xff) != APM_CNT)
                        continue;
 
                /* Check AX against the requested command */
                if ((state->rax & 0xff) != cmd)
                        continue;
 
                return state;
        }
 
        return NULL;
}
 
static void southbridge_smi_gsmi(void)
{
        u32 *ret, *param;
        u8 sub_command;
        em64t101_smm_state_save_area_t *io_smi =
                smi_apmc_find_state_save(APM_CNT_ELOG_GSMI);
 
        if (!io_smi)
                return;
 
        /* Command and return value in EAX */
        ret = (u32 *)&io_smi->rax;
        sub_command = (u8)(*ret >> 8);
 
        /* Parameter buffer in EBX */
        param = (u32 *)&io_smi->rbx;
 
        /* drivers/elog/gsmi.c */
        *ret = gsmi_exec(sub_command, param);
}
 
static void southbridge_smi_store(void)
{
        u8 sub_command, ret;
        em64t101_smm_state_save_area_t *io_smi =
                smi_apmc_find_state_save(APM_CNT_SMMSTORE);
        uint32_t reg_ebx;
 
        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 */
        ret = smmstore_exec(sub_command, (void *)reg_ebx);
        io_smi->rax = ret;
}
 
static void southbridge_smi_apmc(void)
{
        u8 reg8;
 
        reg8 = apm_get_apmc();
        switch (reg8) {
        case APM_CNT_ACPI_DISABLE:
                disable_pm1_control(SCI_EN);
                break;
        case APM_CNT_ACPI_ENABLE:
                enable_pm1_control(SCI_EN);
                break;
        case APM_CNT_ELOG_GSMI:
                if (CONFIG(ELOG_GSMI))
                        southbridge_smi_gsmi();
                break;
        case APM_CNT_SMMSTORE:
                if (CONFIG(SMMSTORE))
                        southbridge_smi_store();
                break;
        }
 
        mainboard_smi_apmc(reg8);
}
 
static void southbridge_smi_pm1(void)
{
        u16 pm1_sts = clear_pm1_status();
 
        /* While OSPM is not active, poweroff immediately
         * on a power button event.
         */
        if (pm1_sts & PWRBTN_STS) {
                /* power button pressed */
                elog_gsmi_add_event(ELOG_TYPE_POWER_BUTTON);
                disable_pm1_control(-1UL);
                enable_pm1_control(SLP_EN | (SLP_TYP_S5 << 10));
        }
}
 
static void southbridge_smi_gpe0(void)
{
        clear_gpe_status();
}
 
static void southbridge_smi_gpi(void)
{
        mainboard_smi_gpi(clear_alt_smi_status());
 
        /* Clear again after mainboard handler */
        clear_alt_smi_status();
}
 
static void southbridge_smi_mc(void)
{
        u32 reg32 = inl(get_pmbase() + SMI_EN);
 
        /* Are microcontroller SMIs enabled? */
        if ((reg32 & MCSMI_EN) == 0)
                return;
 
        printk(BIOS_DEBUG, "Microcontroller SMI.\n");
}
 
static void southbridge_smi_tco(void)
{
        u32 tco_sts = clear_tco_status();
 
        /* Any TCO event? */
        if (!tco_sts)
                return;
 
        // BIOSWR
        if (tco_sts & (1 << 8)) {
                u8 bios_cntl = pci_read_config16(PCH_DEV_LPC, BIOS_CNTL);
 
                if (bios_cntl & 1) {
                        /*
                         * BWE is RW, so the SMI was caused by a
                         * write to BWE, not by a write to the BIOS
                         *
                         * This is the place where we notice someone
                         * is trying to tinker with the BIOS. We are
                         * trying to be nice and just ignore it. A more
                         * resolute answer would be to power down the
                         * box.
                         */
                        printk(BIOS_DEBUG, "Switching back to RO\n");
                        pci_write_config32(PCH_DEV_LPC, BIOS_CNTL,  (bios_cntl & ~1));
                } /* No else for now? */
        } else if (tco_sts & (1 << 3)) { /* TIMEOUT */
                /* Handle TCO timeout */
                printk(BIOS_DEBUG, "TCO Timeout.\n");
        }
}
 
static void southbridge_smi_periodic(void)
{
        u32 reg32 = inl(get_pmbase() + SMI_EN);
 
        /* Are periodic SMIs enabled? */
        if ((reg32 & PERIODIC_EN) == 0)
                return;
 
        printk(BIOS_DEBUG, "Periodic SMI.\n");
}
 
static void southbridge_smi_monitor(void)
{
#define IOTRAP(x) (trap_sts & (1 << x))
        u32 trap_sts, trap_cycle;
        u32 mask = 0;
        int i;
 
        trap_sts = RCBA32(0x1e00); // TRSR - Trap Status Register
        RCBA32(0x1e00) = trap_sts; // Clear trap(s) in TRSR
 
        trap_cycle = RCBA32(0x1e10);
        for (i = 16; i < 20; i++) {
                if (trap_cycle & (1 << i))
                        mask |= (0xff << ((i - 16) << 2));
        }
 
        /* IOTRAP(3) SMI function call */
        if (IOTRAP(3)) {
                if (gnvs && gnvs->smif)
                        io_trap_handler(gnvs->smif); // call function smif
                return;
        }
 
        /* IOTRAP(2) currently unused
         * IOTRAP(1) currently unused */
 
        /* IOTRAP(0) SMIC */
        if (IOTRAP(0)) {
                // It's a write
                if (!(trap_cycle & (1 << 24))) {
                        printk(BIOS_DEBUG, "SMI1 command\n");
                        (void)RCBA32(0x1e18);
                        // data = RCBA32(0x1e18);
                        // data &= mask;
                        // if (smi1)
                        //      southbridge_smi_command(data);
                        // return;
                }
                // Fall through to debug
        }
 
        printk(BIOS_DEBUG, "  trapped io address = 0x%x\n",
               trap_cycle & 0xfffc);
        for (i = 0; i < 4; i++)
                if (IOTRAP(i))
                        printk(BIOS_DEBUG, "  TRAP = %d\n", i);
        printk(BIOS_DEBUG, "  AHBE = %x\n", (trap_cycle >> 16) & 0xf);
        printk(BIOS_DEBUG, "  MASK = 0x%08x\n", mask);
        printk(BIOS_DEBUG, "  read/write: %s\n",
               (trap_cycle & (1 << 24)) ? "read" : "write");
 
        if (!(trap_cycle & (1 << 24))) {
                /* Write Cycle */
                printk(BIOS_DEBUG, "  iotrap written data = 0x%08x\n", RCBA32(0x1e18));
        }
#undef IOTRAP
}
 
typedef void (*smi_handler_t)(void);
 
static smi_handler_t southbridge_smi[32] = {
        NULL,                     //  [0] reserved
        NULL,                     //  [1] reserved
        NULL,                     //  [2] BIOS_STS
        NULL,                     //  [3] LEGACY_USB_STS
        southbridge_smi_sleep,    //  [4] SLP_SMI_STS
        southbridge_smi_apmc,     //  [5] APM_STS
        NULL,                     //  [6] SWSMI_TMR_STS
        NULL,                     //  [7] reserved
        southbridge_smi_pm1,      //  [8] PM1_STS
        southbridge_smi_gpe0,     //  [9] GPE0_STS
        southbridge_smi_gpi,      // [10] GPI_STS
        southbridge_smi_mc,       // [11] MCSMI_STS
        NULL,                     // [12] DEVMON_STS
        southbridge_smi_tco,      // [13] TCO_STS
        southbridge_smi_periodic, // [14] PERIODIC_STS
        NULL,                     // [15] SERIRQ_SMI_STS
        NULL,                     // [16] SMBUS_SMI_STS
        NULL,                     // [17] LEGACY_USB2_STS
        NULL,                     // [18] INTEL_USB2_STS
        NULL,                     // [19] reserved
        NULL,                     // [20] PCI_EXP_SMI_STS
        southbridge_smi_monitor,  // [21] MONITOR_STS
        NULL,                     // [22] reserved
        NULL,                     // [23] reserved
        NULL,                     // [24] reserved
        NULL,                     // [25] EL_SMI_STS
        NULL,                     // [26] SPI_STS
        NULL,                     // [27] reserved
        NULL,                     // [28] reserved
        NULL,                     // [29] reserved
        NULL,                     // [30] reserved
        NULL                      // [31] reserved
};
 
/**
 * @brief Interrupt handler for SMI#
 */
void southbridge_smi_handler(void)
{
        int i;
        u32 smi_sts;
 
        /* We need to clear the SMI status registers, or we won't see what's
         * happening in the following calls.
         */
        smi_sts = clear_smi_status();
 
        /* Call SMI sub handler for each of the status bits */
        for (i = 0; i < 31; i++) {
                if (smi_sts & (1 << i)) {
                        if (southbridge_smi[i]) {
                                southbridge_smi[i]();
                        } else {
                                printk(BIOS_DEBUG,
                                       "SMI_STS[%d] occurred, but no "
                                       "handler available.\n", i);
                        }
                }
        }
}