Archipelago » qemu

#include "qemu-common.h"

#include <strings.h>

#include <stdint.h>

#include "qemu/range.h"

#include "qemu/error-report.h"

#include "hw/pci/shpc.h"

#include "hw/pci/pci.h"

#include "hw/pci/pci_bus.h"

#include "hw/pci/msi.h"

/* TODO: model power only and disabled slot states. */

/* TODO: handle SERR and wakeups */

/* TODO: consider enabling 66MHz support */

/* TODO: remove fully only on state DISABLED and LED off.

 * track state to properly record this. */

/* SHPC Working Register Set */

#define SHPC_BASE_OFFSET  0x00 /* 4 bytes */

#define SHPC_SLOTS_33     0x04 /* 4 bytes. Also encodes PCI-X slots. */

#define SHPC_SLOTS_66     0x08 /* 4 bytes. */

#define SHPC_NSLOTS       0x0C /* 1 byte */

#define SHPC_FIRST_DEV    0x0D /* 1 byte */

#define SHPC_PHYS_SLOT    0x0E /* 2 byte */

#define SHPC_PHYS_NUM_MAX 0x7ff

#define SHPC_PHYS_NUM_UP  0x2000

#define SHPC_PHYS_MRL     0x4000

#define SHPC_PHYS_BUTTON  0x8000

#define SHPC_SEC_BUS      0x10 /* 2 bytes */

#define SHPC_SEC_BUS_33   0x0

#define SHPC_SEC_BUS_66   0x1 /* Unused */

#define SHPC_SEC_BUS_MASK 0x7

#define SHPC_MSI_CTL      0x12 /* 1 byte */

#define SHPC_PROG_IFC     0x13 /* 1 byte */

#define SHPC_PROG_IFC_1_0 0x1

#define SHPC_CMD_CODE     0x14 /* 1 byte */

#define SHPC_CMD_TRGT     0x15 /* 1 byte */

#define SHPC_CMD_TRGT_MIN 0x1

#define SHPC_CMD_TRGT_MAX 0x1f

#define SHPC_CMD_STATUS   0x16 /* 2 bytes */

#define SHPC_CMD_STATUS_BUSY          0x1

#define SHPC_CMD_STATUS_MRL_OPEN      0x2

#define SHPC_CMD_STATUS_INVALID_CMD   0x4

#define SHPC_CMD_STATUS_INVALID_MODE  0x8

#define SHPC_INT_LOCATOR  0x18 /* 4 bytes */

#define SHPC_INT_COMMAND  0x1

#define SHPC_SERR_LOCATOR 0x1C /* 4 bytes */

#define SHPC_SERR_INT     0x20 /* 4 bytes */

#define SHPC_INT_DIS      0x1

#define SHPC_SERR_DIS     0x2

#define SHPC_CMD_INT_DIS  0x4

#define SHPC_ARB_SERR_DIS 0x8

#define SHPC_CMD_DETECTED 0x10000

#define SHPC_ARB_DETECTED 0x20000

 /* 4 bytes * slot # (start from 0) */

#define SHPC_SLOT_REG(s)         (0x24 + (s) * 4)

 /* 2 bytes */

#define SHPC_SLOT_STATUS(s)       (0x0 + SHPC_SLOT_REG(s))

/* Same slot state masks are used for command and status registers */

#define SHPC_SLOT_STATE_MASK     0x03

#define SHPC_SLOT_STATE_SHIFT \

    (ffs(SHPC_SLOT_STATE_MASK) - 1)

#define SHPC_STATE_NO       0x0

#define SHPC_STATE_PWRONLY  0x1

#define SHPC_STATE_ENABLED  0x2

#define SHPC_STATE_DISABLED 0x3

#define SHPC_SLOT_PWR_LED_MASK   0xC

#define SHPC_SLOT_PWR_LED_SHIFT \

    (ffs(SHPC_SLOT_PWR_LED_MASK) - 1)

#define SHPC_SLOT_ATTN_LED_MASK  0x30

#define SHPC_SLOT_ATTN_LED_SHIFT \

    (ffs(SHPC_SLOT_ATTN_LED_MASK) - 1)

#define SHPC_LED_NO     0x0

#define SHPC_LED_ON     0x1

#define SHPC_LED_BLINK  0x2

#define SHPC_LED_OFF    0x3

#define SHPC_SLOT_STATUS_PWR_FAULT      0x40

#define SHPC_SLOT_STATUS_BUTTON         0x80

#define SHPC_SLOT_STATUS_MRL_OPEN       0x100

#define SHPC_SLOT_STATUS_66             0x200

#define SHPC_SLOT_STATUS_PRSNT_MASK     0xC00

#define SHPC_SLOT_STATUS_PRSNT_EMPTY    0x3

#define SHPC_SLOT_STATUS_PRSNT_25W      0x1

#define SHPC_SLOT_STATUS_PRSNT_15W      0x2

#define SHPC_SLOT_STATUS_PRSNT_7_5W     0x0

#define SHPC_SLOT_STATUS_PRSNT_PCIX     0x3000

 /* 1 byte */

#define SHPC_SLOT_EVENT_LATCH(s)        (0x2 + SHPC_SLOT_REG(s))

 /* 1 byte */

#define SHPC_SLOT_EVENT_SERR_INT_DIS(d, s) (0x3 + SHPC_SLOT_REG(s))

#define SHPC_SLOT_EVENT_PRESENCE        0x01

#define SHPC_SLOT_EVENT_ISOLATED_FAULT  0x02

#define SHPC_SLOT_EVENT_BUTTON          0x04

#define SHPC_SLOT_EVENT_MRL             0x08

#define SHPC_SLOT_EVENT_CONNECTED_FAULT 0x10

/* Bits below are used for Serr/Int disable only */

#define SHPC_SLOT_EVENT_MRL_SERR_DIS    0x20

#define SHPC_SLOT_EVENT_CONNECTED_FAULT_SERR_DIS 0x40

#define SHPC_MIN_SLOTS        1

#define SHPC_MAX_SLOTS        31

#define SHPC_SIZEOF(d)    SHPC_SLOT_REG((d)->shpc->nslots)

/* SHPC Slot identifiers */

/* Hotplug supported at 31 slots out of the total 32.  We reserve slot 0,

   and give the rest of them physical *and* pci numbers starting from 1, so

   they match logical numbers.  Note: this means that multiple slots must have

   different chassis number values, to make chassis+physical slot unique.

   TODO: make this configurable? */

#define SHPC_IDX_TO_LOGICAL(slot) ((slot) + 1)

#define SHPC_LOGICAL_TO_IDX(target) ((target) - 1)

#define SHPC_IDX_TO_PCI(slot) ((slot) + 1)

#define SHPC_PCI_TO_IDX(pci_slot) ((pci_slot) - 1)

#define SHPC_IDX_TO_PHYSICAL(slot) ((slot) + 1)

static int roundup_pow_of_two(int x)

{

    x |= (x >> 1);

    x |= (x >> 2);

    x |= (x >> 4);

    x |= (x >> 8);

    x |= (x >> 16);

    return x + 1;

}

static uint16_t shpc_get_status(SHPCDevice *shpc, int slot, uint16_t msk)

{

    uint8_t *status = shpc->config + SHPC_SLOT_STATUS(slot);

    return (pci_get_word(status) & msk) >> (ffs(msk) - 1);

}

static void shpc_set_status(SHPCDevice *shpc,

                            int slot, uint8_t value, uint16_t msk)

{

    uint8_t *status = shpc->config + SHPC_SLOT_STATUS(slot);

    pci_word_test_and_clear_mask(status, msk);

    pci_word_test_and_set_mask(status, value << (ffs(msk) - 1));

}

static void shpc_interrupt_update(PCIDevice *d)

{

    SHPCDevice *shpc = d->shpc;

    int slot;

    int level = 0;

    uint32_t serr_int;

    uint32_t int_locator = 0;

    /* Update interrupt locator register */

    for (slot = 0; slot < shpc->nslots; ++slot) {

        uint8_t event = shpc->config[SHPC_SLOT_EVENT_LATCH(slot)];

        uint8_t disable = shpc->config[SHPC_SLOT_EVENT_SERR_INT_DIS(d, slot)];

        uint32_t mask = 1 << SHPC_IDX_TO_LOGICAL(slot);

        if (event & ~disable) {

            int_locator |= mask;

        }

    }

    serr_int = pci_get_long(shpc->config + SHPC_SERR_INT);

    if ((serr_int & SHPC_CMD_DETECTED) && !(serr_int & SHPC_CMD_INT_DIS)) {

        int_locator |= SHPC_INT_COMMAND;

    }

    pci_set_long(shpc->config + SHPC_INT_LOCATOR, int_locator);

    level = (!(serr_int & SHPC_INT_DIS) && int_locator) ? 1 : 0;

    if (msi_enabled(d) && shpc->msi_requested != level)

        msi_notify(d, 0);

    else

        qemu_set_irq(d->irq[0], level);

    shpc->msi_requested = level;

}

static void shpc_set_sec_bus_speed(SHPCDevice *shpc, uint8_t speed)

{

    switch (speed) {

    case SHPC_SEC_BUS_33:

        shpc->config[SHPC_SEC_BUS] &= ~SHPC_SEC_BUS_MASK;

        shpc->config[SHPC_SEC_BUS] |= speed;

        break;

    default:

        pci_word_test_and_set_mask(shpc->config + SHPC_CMD_STATUS,

                                   SHPC_CMD_STATUS_INVALID_MODE);

    }

}

void shpc_reset(PCIDevice *d)

{

    SHPCDevice *shpc = d->shpc;

    int nslots = shpc->nslots;

    int i;

    memset(shpc->config, 0, SHPC_SIZEOF(d));

    pci_set_byte(shpc->config + SHPC_NSLOTS, nslots);

    pci_set_long(shpc->config + SHPC_SLOTS_33, nslots);

    pci_set_long(shpc->config + SHPC_SLOTS_66, 0);

    pci_set_byte(shpc->config + SHPC_FIRST_DEV, SHPC_IDX_TO_PCI(0));

    pci_set_word(shpc->config + SHPC_PHYS_SLOT,

                 SHPC_IDX_TO_PHYSICAL(0) |

                 SHPC_PHYS_NUM_UP |

                 SHPC_PHYS_MRL |

                 SHPC_PHYS_BUTTON);

    pci_set_long(shpc->config + SHPC_SERR_INT, SHPC_INT_DIS |

                 SHPC_SERR_DIS |

                 SHPC_CMD_INT_DIS |

                 SHPC_ARB_SERR_DIS);

    pci_set_byte(shpc->config + SHPC_PROG_IFC, SHPC_PROG_IFC_1_0);

    pci_set_word(shpc->config + SHPC_SEC_BUS, SHPC_SEC_BUS_33);

    for (i = 0; i < shpc->nslots; ++i) {

        pci_set_byte(shpc->config + SHPC_SLOT_EVENT_SERR_INT_DIS(d, i),

                     SHPC_SLOT_EVENT_PRESENCE |

                     SHPC_SLOT_EVENT_ISOLATED_FAULT |

                     SHPC_SLOT_EVENT_BUTTON |

                     SHPC_SLOT_EVENT_MRL |

                     SHPC_SLOT_EVENT_CONNECTED_FAULT |

                     SHPC_SLOT_EVENT_MRL_SERR_DIS |

                     SHPC_SLOT_EVENT_CONNECTED_FAULT_SERR_DIS);

        if (shpc->sec_bus->devices[PCI_DEVFN(SHPC_IDX_TO_PCI(i), 0)]) {

            shpc_set_status(shpc, i, SHPC_STATE_ENABLED, SHPC_SLOT_STATE_MASK);

            shpc_set_status(shpc, i, 0, SHPC_SLOT_STATUS_MRL_OPEN);

            shpc_set_status(shpc, i, SHPC_SLOT_STATUS_PRSNT_7_5W,

                            SHPC_SLOT_STATUS_PRSNT_MASK);

            shpc_set_status(shpc, i, SHPC_LED_ON, SHPC_SLOT_PWR_LED_MASK);

        } else {

            shpc_set_status(shpc, i, SHPC_STATE_DISABLED, SHPC_SLOT_STATE_MASK);

            shpc_set_status(shpc, i, 1, SHPC_SLOT_STATUS_MRL_OPEN);

            shpc_set_status(shpc, i, SHPC_SLOT_STATUS_PRSNT_EMPTY,

                            SHPC_SLOT_STATUS_PRSNT_MASK);

            shpc_set_status(shpc, i, SHPC_LED_OFF, SHPC_SLOT_PWR_LED_MASK);

        }

        shpc_set_status(shpc, i, 0, SHPC_SLOT_STATUS_66);

    }

    shpc_set_sec_bus_speed(shpc, SHPC_SEC_BUS_33);

    shpc->msi_requested = 0;

    shpc_interrupt_update(d);

}

static void shpc_invalid_command(SHPCDevice *shpc)

{

    pci_word_test_and_set_mask(shpc->config + SHPC_CMD_STATUS,

                               SHPC_CMD_STATUS_INVALID_CMD);

}

static void shpc_free_devices_in_slot(SHPCDevice *shpc, int slot)

{

    int devfn;

    int pci_slot = SHPC_IDX_TO_PCI(slot);

    for (devfn = PCI_DEVFN(pci_slot, 0);

         devfn <= PCI_DEVFN(pci_slot, PCI_FUNC_MAX - 1);

         ++devfn) {

        PCIDevice *affected_dev = shpc->sec_bus->devices[devfn];

        if (affected_dev) {

            qdev_free(&affected_dev->qdev);

        }

    }

}

static void shpc_slot_command(SHPCDevice *shpc, uint8_t target,

                              uint8_t state, uint8_t power, uint8_t attn)

{

    uint8_t current_state;

    int slot = SHPC_LOGICAL_TO_IDX(target);

    if (target < SHPC_CMD_TRGT_MIN || slot >= shpc->nslots) {

        shpc_invalid_command(shpc);

        return;

    }

    current_state = shpc_get_status(shpc, slot, SHPC_SLOT_STATE_MASK);

    if (current_state == SHPC_STATE_ENABLED && state == SHPC_STATE_PWRONLY) {

        shpc_invalid_command(shpc);

        return;

    }

    switch (power) {

    case SHPC_LED_NO:

        break;

    default:

        /* TODO: send event to monitor */

        shpc_set_status(shpc, slot, power, SHPC_SLOT_PWR_LED_MASK);

    }

    switch (attn) {

    case SHPC_LED_NO:

        break;

    default:

        /* TODO: send event to monitor */

        shpc_set_status(shpc, slot, attn, SHPC_SLOT_ATTN_LED_MASK);

    }

    if ((current_state == SHPC_STATE_DISABLED && state == SHPC_STATE_PWRONLY) ||

        (current_state == SHPC_STATE_DISABLED && state == SHPC_STATE_ENABLED)) {

        shpc_set_status(shpc, slot, state, SHPC_SLOT_STATE_MASK);

    } else if ((current_state == SHPC_STATE_ENABLED ||

                current_state == SHPC_STATE_PWRONLY) &&

               state == SHPC_STATE_DISABLED) {

        shpc_set_status(shpc, slot, state, SHPC_SLOT_STATE_MASK);

        power = shpc_get_status(shpc, slot, SHPC_SLOT_PWR_LED_MASK);

        /* TODO: track what monitor requested. */

        /* Look at LED to figure out whether it's ok to remove the device. */

        if (power == SHPC_LED_OFF) {

            shpc_free_devices_in_slot(shpc, slot);

            shpc_set_status(shpc, slot, 1, SHPC_SLOT_STATUS_MRL_OPEN);

            shpc_set_status(shpc, slot, SHPC_SLOT_STATUS_PRSNT_EMPTY,

                            SHPC_SLOT_STATUS_PRSNT_MASK);

            shpc->config[SHPC_SLOT_EVENT_LATCH(slot)] |=

                SHPC_SLOT_EVENT_BUTTON |

                SHPC_SLOT_EVENT_MRL |

                SHPC_SLOT_EVENT_PRESENCE;

        }

    }

}

static void shpc_command(SHPCDevice *shpc)

{

    uint8_t code = pci_get_byte(shpc->config + SHPC_CMD_CODE);

    uint8_t speed;

    uint8_t target;

    uint8_t attn;

    uint8_t power;

    uint8_t state;

    int i;

    /* Clear status from the previous command. */

    pci_word_test_and_clear_mask(shpc->config + SHPC_CMD_STATUS,

                                 SHPC_CMD_STATUS_BUSY |

                                 SHPC_CMD_STATUS_MRL_OPEN |

                                 SHPC_CMD_STATUS_INVALID_CMD |

                                 SHPC_CMD_STATUS_INVALID_MODE);

    switch (code) {

    case 0x00 ... 0x3f:

        target = shpc->config[SHPC_CMD_TRGT] & SHPC_CMD_TRGT_MAX;

        state = (code & SHPC_SLOT_STATE_MASK) >> SHPC_SLOT_STATE_SHIFT;

        power = (code & SHPC_SLOT_PWR_LED_MASK) >> SHPC_SLOT_PWR_LED_SHIFT;

        attn = (code & SHPC_SLOT_ATTN_LED_MASK) >> SHPC_SLOT_ATTN_LED_SHIFT;

        shpc_slot_command(shpc, target, state, power, attn);

        break;

    case 0x40 ... 0x47:

        speed = code & SHPC_SEC_BUS_MASK;

        shpc_set_sec_bus_speed(shpc, speed);

        break;

    case 0x48:

        /* Power only all slots */

        /* first verify no slots are enabled */

        for (i = 0; i < shpc->nslots; ++i) {

            state = shpc_get_status(shpc, i, SHPC_SLOT_STATE_MASK);

            if (state == SHPC_STATE_ENABLED) {

                shpc_invalid_command(shpc);

                goto done;

            }

        }

        for (i = 0; i < shpc->nslots; ++i) {

            if (!(shpc_get_status(shpc, i, SHPC_SLOT_STATUS_MRL_OPEN))) {

                shpc_slot_command(shpc, i + SHPC_CMD_TRGT_MIN,

                                  SHPC_STATE_PWRONLY, SHPC_LED_ON, SHPC_LED_NO);

            } else {

                shpc_slot_command(shpc, i + SHPC_CMD_TRGT_MIN,

                                  SHPC_STATE_NO, SHPC_LED_OFF, SHPC_LED_NO);

            }

        }

        break;

    case 0x49:

        /* Enable all slots */

        /* TODO: Spec says this shall fail if some are already enabled.

         * This doesn't make sense - why not? a spec bug? */

        for (i = 0; i < shpc->nslots; ++i) {

            state = shpc_get_status(shpc, i, SHPC_SLOT_STATE_MASK);

            if (state == SHPC_STATE_ENABLED) {

                shpc_invalid_command(shpc);

                goto done;

            }

        }

        for (i = 0; i < shpc->nslots; ++i) {

            if (!(shpc_get_status(shpc, i, SHPC_SLOT_STATUS_MRL_OPEN))) {

                shpc_slot_command(shpc, i + SHPC_CMD_TRGT_MIN,

                                  SHPC_STATE_ENABLED, SHPC_LED_ON, SHPC_LED_NO);

            } else {

                shpc_slot_command(shpc, i + SHPC_CMD_TRGT_MIN,

                                  SHPC_STATE_NO, SHPC_LED_OFF, SHPC_LED_NO);

            }

        }

        break;

    default:

        shpc_invalid_command(shpc);

        break;

    }

done:

    pci_long_test_and_set_mask(shpc->config + SHPC_SERR_INT, SHPC_CMD_DETECTED);

}

static void shpc_write(PCIDevice *d, unsigned addr, uint64_t val, int l)

{

    SHPCDevice *shpc = d->shpc;

    int i;

    if (addr >= SHPC_SIZEOF(d)) {

        return;

    }

    l = MIN(l, SHPC_SIZEOF(d) - addr);

    /* TODO: code duplicated from pci.c */

    for (i = 0; i < l; val >>= 8, ++i) {

        unsigned a = addr + i;

        uint8_t wmask = shpc->wmask[a];

        uint8_t w1cmask = shpc->w1cmask[a];

        assert(!(wmask & w1cmask));

        shpc->config[a] = (shpc->config[a] & ~wmask) | (val & wmask);

        shpc->config[a] &= ~(val & w1cmask); /* W1C: Write 1 to Clear */

    }

    if (ranges_overlap(addr, l, SHPC_CMD_CODE, 2)) {

        shpc_command(shpc);

    }

    shpc_interrupt_update(d);

}

static uint64_t shpc_read(PCIDevice *d, unsigned addr, int l)

{

    uint64_t val = 0x0;

    if (addr >= SHPC_SIZEOF(d)) {

        return val;

    }

    l = MIN(l, SHPC_SIZEOF(d) - addr);

    memcpy(&val, d->shpc->config + addr, l);

    return val;

}

/* SHPC Bridge Capability */

#define SHPC_CAP_LENGTH 0x08

#define SHPC_CAP_DWORD_SELECT 0x2 /* 1 byte */

#define SHPC_CAP_CxP 0x3 /* 1 byte: CSP, CIP */

#define SHPC_CAP_DWORD_DATA 0x4 /* 4 bytes */

#define SHPC_CAP_CSP_MASK 0x4

#define SHPC_CAP_CIP_MASK 0x8

static uint8_t shpc_cap_dword(PCIDevice *d)

{

    return pci_get_byte(d->config + d->shpc->cap + SHPC_CAP_DWORD_SELECT);

}

/* Update dword data capability register */

static void shpc_cap_update_dword(PCIDevice *d)

{

    unsigned data;

    data = shpc_read(d, shpc_cap_dword(d) * 4, 4);

    pci_set_long(d->config  + d->shpc->cap + SHPC_CAP_DWORD_DATA, data);

}

/* Add SHPC capability to the config space for the device. */

static int shpc_cap_add_config(PCIDevice *d)

{

    uint8_t *config;

    int config_offset;

    config_offset = pci_add_capability(d, PCI_CAP_ID_SHPC,

                                       0, SHPC_CAP_LENGTH);

    if (config_offset < 0) {

        return config_offset;

    }

    config = d->config + config_offset;

    pci_set_byte(config + SHPC_CAP_DWORD_SELECT, 0);

    pci_set_byte(config + SHPC_CAP_CxP, 0);

    pci_set_long(config + SHPC_CAP_DWORD_DATA, 0);

    d->shpc->cap = config_offset;

    /* Make dword select and data writeable. */

    pci_set_byte(d->wmask + config_offset + SHPC_CAP_DWORD_SELECT, 0xff);

    pci_set_long(d->wmask + config_offset + SHPC_CAP_DWORD_DATA, 0xffffffff);

    return 0;

}

static uint64_t shpc_mmio_read(void *opaque, hwaddr addr,

                               unsigned size)

{

    return shpc_read(opaque, addr, size);

}

static void shpc_mmio_write(void *opaque, hwaddr addr,

                            uint64_t val, unsigned size)

{

    shpc_write(opaque, addr, val, size);

}

static const MemoryRegionOps shpc_mmio_ops = {

    .read = shpc_mmio_read,

    .write = shpc_mmio_write,

    .endianness = DEVICE_LITTLE_ENDIAN,

    .valid = {

        /* SHPC ECN requires dword accesses, but the original 1.0 spec doesn't.

         * It's easier to suppport all sizes than worry about it. */

        .min_access_size = 1,

        .max_access_size = 4,

    },

};

static int shpc_device_hotplug(DeviceState *qdev, PCIDevice *affected_dev,

                               PCIHotplugState hotplug_state)

{

    int pci_slot = PCI_SLOT(affected_dev->devfn);

    uint8_t state;

    uint8_t led;

    PCIDevice *d = DO_UPCAST(PCIDevice, qdev, qdev);

    SHPCDevice *shpc = d->shpc;

    int slot = SHPC_PCI_TO_IDX(pci_slot);

    if (pci_slot < SHPC_IDX_TO_PCI(0) || slot >= shpc->nslots) {

        error_report("Unsupported PCI slot %d for standard hotplug "

                     "controller. Valid slots are between %d and %d.",

                     pci_slot, SHPC_IDX_TO_PCI(0),

                     SHPC_IDX_TO_PCI(shpc->nslots) - 1);

        return -1;

    }

    /* Don't send event when device is enabled during qemu machine creation:

     * it is present on boot, no hotplug event is necessary. We do send an

     * event when the device is disabled later. */

    if (hotplug_state == PCI_COLDPLUG_ENABLED) {

        shpc_set_status(shpc, slot, 0, SHPC_SLOT_STATUS_MRL_OPEN);

        shpc_set_status(shpc, slot, SHPC_SLOT_STATUS_PRSNT_7_5W,

                        SHPC_SLOT_STATUS_PRSNT_MASK);

        return 0;

    }

    if (hotplug_state == PCI_HOTPLUG_DISABLED) {

        shpc->config[SHPC_SLOT_EVENT_LATCH(slot)] |= SHPC_SLOT_EVENT_BUTTON;

        state = shpc_get_status(shpc, slot, SHPC_SLOT_STATE_MASK);

        led = shpc_get_status(shpc, slot, SHPC_SLOT_PWR_LED_MASK);

        if (state == SHPC_STATE_DISABLED && led == SHPC_LED_OFF) {

            shpc_free_devices_in_slot(shpc, slot);

            shpc_set_status(shpc, slot, 1, SHPC_SLOT_STATUS_MRL_OPEN);

            shpc_set_status(shpc, slot, SHPC_SLOT_STATUS_PRSNT_EMPTY,

                            SHPC_SLOT_STATUS_PRSNT_MASK);

            shpc->config[SHPC_SLOT_EVENT_LATCH(slot)] |=

                SHPC_SLOT_EVENT_MRL |

                SHPC_SLOT_EVENT_PRESENCE;

        }

    } else {

        /* This could be a cancellation of the previous removal.

         * We check MRL state to figure out. */

        if (shpc_get_status(shpc, slot, SHPC_SLOT_STATUS_MRL_OPEN)) {

            shpc_set_status(shpc, slot, 0, SHPC_SLOT_STATUS_MRL_OPEN);

            shpc_set_status(shpc, slot, SHPC_SLOT_STATUS_PRSNT_7_5W,

                            SHPC_SLOT_STATUS_PRSNT_MASK);

            shpc->config[SHPC_SLOT_EVENT_LATCH(slot)] |=

                SHPC_SLOT_EVENT_BUTTON |

                SHPC_SLOT_EVENT_MRL |

                SHPC_SLOT_EVENT_PRESENCE;

        } else {

            /* Press attention button to cancel removal */

            shpc->config[SHPC_SLOT_EVENT_LATCH(slot)] |=

                SHPC_SLOT_EVENT_BUTTON;

        }

    }

    shpc_set_status(shpc, slot, 0, SHPC_SLOT_STATUS_66);

    shpc_interrupt_update(d);

    return 0;

}

/* Initialize the SHPC structure in bridge's BAR. */

int shpc_init(PCIDevice *d, PCIBus *sec_bus, MemoryRegion *bar, unsigned offset)

{

    int i, ret;

    int nslots = SHPC_MAX_SLOTS; /* TODO: qdev property? */

    SHPCDevice *shpc = d->shpc = g_malloc0(sizeof(*d->shpc));

    shpc->sec_bus = sec_bus;

    ret = shpc_cap_add_config(d);

    if (ret) {

        g_free(d->shpc);

        return ret;

    }

    if (nslots < SHPC_MIN_SLOTS) {

        return 0;

    }

    if (nslots > SHPC_MAX_SLOTS ||

        SHPC_IDX_TO_PCI(nslots) > PCI_SLOT_MAX) {

        /* TODO: report an error mesage that makes sense. */

        return -EINVAL;

    }

    shpc->nslots = nslots;

    shpc->config = g_malloc0(SHPC_SIZEOF(d));

    shpc->cmask = g_malloc0(SHPC_SIZEOF(d));

    shpc->wmask = g_malloc0(SHPC_SIZEOF(d));

    shpc->w1cmask = g_malloc0(SHPC_SIZEOF(d));

    shpc_reset(d);

    pci_set_long(shpc->config + SHPC_BASE_OFFSET, offset);

    pci_set_byte(shpc->wmask + SHPC_CMD_CODE, 0xff);

    pci_set_byte(shpc->wmask + SHPC_CMD_TRGT, SHPC_CMD_TRGT_MAX);

    pci_set_byte(shpc->wmask + SHPC_CMD_TRGT, SHPC_CMD_TRGT_MAX);

    pci_set_long(shpc->wmask + SHPC_SERR_INT,

                 SHPC_INT_DIS |

                 SHPC_SERR_DIS |

                 SHPC_CMD_INT_DIS |

                 SHPC_ARB_SERR_DIS);

    pci_set_long(shpc->w1cmask + SHPC_SERR_INT,

                 SHPC_CMD_DETECTED |

                 SHPC_ARB_DETECTED);

    for (i = 0; i < nslots; ++i) {

        pci_set_byte(shpc->wmask +

                     SHPC_SLOT_EVENT_SERR_INT_DIS(d, i),

                     SHPC_SLOT_EVENT_PRESENCE |

                     SHPC_SLOT_EVENT_ISOLATED_FAULT |

                     SHPC_SLOT_EVENT_BUTTON |

                     SHPC_SLOT_EVENT_MRL |

                     SHPC_SLOT_EVENT_CONNECTED_FAULT |

                     SHPC_SLOT_EVENT_MRL_SERR_DIS |

                     SHPC_SLOT_EVENT_CONNECTED_FAULT_SERR_DIS);

        pci_set_byte(shpc->w1cmask +

                     SHPC_SLOT_EVENT_LATCH(i),

                     SHPC_SLOT_EVENT_PRESENCE |

                     SHPC_SLOT_EVENT_ISOLATED_FAULT |

                     SHPC_SLOT_EVENT_BUTTON |

                     SHPC_SLOT_EVENT_MRL |

                     SHPC_SLOT_EVENT_CONNECTED_FAULT);

    }

    /* TODO: init cmask */

    memory_region_init_io(&shpc->mmio, &shpc_mmio_ops, d, "shpc-mmio",

                          SHPC_SIZEOF(d));

    shpc_cap_update_dword(d);

    memory_region_add_subregion(bar, offset, &shpc->mmio);

    pci_bus_hotplug(sec_bus, shpc_device_hotplug, &d->qdev);

    d->cap_present |= QEMU_PCI_CAP_SHPC;

    return 0;

}

int shpc_bar_size(PCIDevice *d)

{

    return roundup_pow_of_two(SHPC_SLOT_REG(SHPC_MAX_SLOTS));

}

void shpc_cleanup(PCIDevice *d, MemoryRegion *bar)

{

    SHPCDevice *shpc = d->shpc;

    d->cap_present &= ~QEMU_PCI_CAP_SHPC;

    memory_region_del_subregion(bar, &shpc->mmio);

    /* TODO: cleanup config space changes? */

    g_free(shpc->config);

    g_free(shpc->cmask);

    g_free(shpc->wmask);

    g_free(shpc->w1cmask);

    memory_region_destroy(&shpc->mmio);

    g_free(shpc);

}

void shpc_cap_write_config(PCIDevice *d, uint32_t addr, uint32_t val, int l)

{

    if (!ranges_overlap(addr, l, d->shpc->cap, SHPC_CAP_LENGTH)) {

        return;

    }

    if (ranges_overlap(addr, l, d->shpc->cap + SHPC_CAP_DWORD_DATA, 4)) {

        unsigned dword_data;

        dword_data = pci_get_long(d->shpc->config + d->shpc->cap

                                  + SHPC_CAP_DWORD_DATA);

        shpc_write(d, shpc_cap_dword(d) * 4, dword_data, 4);

    }

    /* Update cap dword data in case guest is going to read it. */

    shpc_cap_update_dword(d);

}

static void shpc_save(QEMUFile *f, void *pv, size_t size)

{

    PCIDevice *d = container_of(pv, PCIDevice, shpc);

    qemu_put_buffer(f, d->shpc->config, SHPC_SIZEOF(d));

}

static int shpc_load(QEMUFile *f, void *pv, size_t size)

{

    PCIDevice *d = container_of(pv, PCIDevice, shpc);

    int ret = qemu_get_buffer(f, d->shpc->config, SHPC_SIZEOF(d));

    if (ret != SHPC_SIZEOF(d)) {

        return -EINVAL;

    }

    /* Make sure we don't lose notifications. An extra interrupt is harmless. */

    d->shpc->msi_requested = 0;

    shpc_interrupt_update(d);

    return 0;

}

VMStateInfo shpc_vmstate_info = {

    .name = "shpc",

    .get  = shpc_load,

    .put  = shpc_save,

};