Archipelago » qemu

/*

 * pcie.c

 *

 * Copyright (c) 2010 Isaku Yamahata <yamahata at valinux co jp>

 *                    VA Linux Systems Japan K.K.

 *

 * 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; either version 2 of the License, or

 * (at your option) any later version.

 *

 * 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, see <http://www.gnu.org/licenses/>.

 */

#include "qemu-common.h"

#include "pci_bridge.h"

#include "pcie.h"

#include "msix.h"

#include "msi.h"

#include "pci_internals.h"

#include "pcie_regs.h"

#include "range.h"

//#define DEBUG_PCIE

#ifdef DEBUG_PCIE

# define PCIE_DPRINTF(fmt, ...)                                         \

    fprintf(stderr, "%s:%d " fmt, __func__, __LINE__, ## __VA_ARGS__)

#else

# define PCIE_DPRINTF(fmt, ...) do {} while (0)

#endif

#define PCIE_DEV_PRINTF(dev, fmt, ...)                                  \

    PCIE_DPRINTF("%s:%x "fmt, (dev)->name, (dev)->devfn, ## __VA_ARGS__)

/***************************************************************************

 * pci express capability helper functions

 */

int pcie_cap_init(PCIDevice *dev, uint8_t offset, uint8_t type, uint8_t port)

{

    int pos;

    uint8_t *exp_cap;

    assert(pci_is_express(dev));

    pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset,

                                 PCI_EXP_VER2_SIZEOF);

    if (pos < 0) {

        return pos;

    }

    dev->exp.exp_cap = pos;

    exp_cap = dev->config + pos;

    /* capability register

       interrupt message number defaults to 0 */

    pci_set_word(exp_cap + PCI_EXP_FLAGS,

                 ((type << PCI_EXP_FLAGS_TYPE_SHIFT) & PCI_EXP_FLAGS_TYPE) |

                 PCI_EXP_FLAGS_VER2);

    /* device capability register

     * table 7-12:

     * roll based error reporting bit must be set by all

     * Functions conforming to the ECN, PCI Express Base

     * Specification, Revision 1.1., or subsequent PCI Express Base

     * Specification revisions.

     */

    pci_set_long(exp_cap + PCI_EXP_DEVCAP, PCI_EXP_DEVCAP_RBER);

    pci_set_long(exp_cap + PCI_EXP_LNKCAP,

                 (port << PCI_EXP_LNKCAP_PN_SHIFT) |

                 PCI_EXP_LNKCAP_ASPMS_0S |

                 PCI_EXP_LNK_MLW_1 |

                 PCI_EXP_LNK_LS_25);

    pci_set_word(exp_cap + PCI_EXP_LNKSTA,

                 PCI_EXP_LNK_MLW_1 | PCI_EXP_LNK_LS_25);

    pci_set_long(exp_cap + PCI_EXP_DEVCAP2,

                 PCI_EXP_DEVCAP2_EFF | PCI_EXP_DEVCAP2_EETLPP);

    pci_set_word(dev->wmask + pos, PCI_EXP_DEVCTL2_EETLPPB);

    return pos;

}

void pcie_cap_exit(PCIDevice *dev)

{

    pci_del_capability(dev, PCI_CAP_ID_EXP, PCI_EXP_VER2_SIZEOF);

}

uint8_t pcie_cap_get_type(const PCIDevice *dev)

{

    uint32_t pos = dev->exp.exp_cap;

    assert(pos > 0);

    return (pci_get_word(dev->config + pos + PCI_EXP_FLAGS) &

            PCI_EXP_FLAGS_TYPE) >> PCI_EXP_FLAGS_TYPE_SHIFT;

}

/* MSI/MSI-X */

/* pci express interrupt message number */

/* 7.8.2 PCI Express Capabilities Register: Interrupt Message Number */

void pcie_cap_flags_set_vector(PCIDevice *dev, uint8_t vector)

{

    uint8_t *exp_cap = dev->config + dev->exp.exp_cap;

    assert(vector < 32);

    pci_word_test_and_clear_mask(exp_cap + PCI_EXP_FLAGS, PCI_EXP_FLAGS_IRQ);

    pci_word_test_and_set_mask(exp_cap + PCI_EXP_FLAGS,

                               vector << PCI_EXP_FLAGS_IRQ_SHIFT);

}

uint8_t pcie_cap_flags_get_vector(PCIDevice *dev)

{

    return (pci_get_word(dev->config + dev->exp.exp_cap + PCI_EXP_FLAGS) &

            PCI_EXP_FLAGS_IRQ) >> PCI_EXP_FLAGS_IRQ_SHIFT;

}

void pcie_cap_deverr_init(PCIDevice *dev)

{

    uint32_t pos = dev->exp.exp_cap;

    pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP,

                               PCI_EXP_DEVCAP_RBER);

    pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL,

                               PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |

                               PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);

    pci_long_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_DEVSTA,

                               PCI_EXP_DEVSTA_CED | PCI_EXP_DEVSTA_NFED |

                               PCI_EXP_DEVSTA_URD | PCI_EXP_DEVSTA_URD);

}

void pcie_cap_deverr_reset(PCIDevice *dev)

{

    uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;

    pci_long_test_and_clear_mask(devctl,

                                 PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |

                                 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);

}

static void hotplug_event_update_event_status(PCIDevice *dev)

{

    uint32_t pos = dev->exp.exp_cap;

    uint8_t *exp_cap = dev->config + pos;

    uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);

    uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);

    dev->exp.hpev_notified = (sltctl & PCI_EXP_SLTCTL_HPIE) &&

        (sltsta & sltctl & PCI_EXP_HP_EV_SUPPORTED);

}

static void hotplug_event_notify(PCIDevice *dev)

{

    bool prev = dev->exp.hpev_notified;

    hotplug_event_update_event_status(dev);

    if (prev == dev->exp.hpev_notified) {

        return;

    }

    /* Note: the logic above does not take into account whether interrupts

     * are masked. The result is that interrupt will be sent when it is

     * subsequently unmasked. This appears to be legal: Section 6.7.3.4:

     * The Port may optionally send an MSI when there are hot-plug events that

     * occur while interrupt generation is disabled, and interrupt generation is

     * subsequently enabled. */

    if (msix_enabled(dev)) {

        msix_notify(dev, pcie_cap_flags_get_vector(dev));

    } else if (msi_enabled(dev)) {

        msi_notify(dev, pcie_cap_flags_get_vector(dev));

    } else {

        qemu_set_irq(dev->irq[dev->exp.hpev_intx], dev->exp.hpev_notified);

    }

}

static void hotplug_event_clear(PCIDevice *dev)

{

    hotplug_event_update_event_status(dev);

    if (!msix_enabled(dev) && !msi_enabled(dev) && !dev->exp.hpev_notified) {

        qemu_set_irq(dev->irq[dev->exp.hpev_intx], 0);

    }

}

/*

 * A PCI Express Hot-Plug Event has occurred, so update slot status register

 * and notify OS of the event if necessary.

 *

 * 6.7.3 PCI Express Hot-Plug Events

 * 6.7.3.4 Software Notification of Hot-Plug Events

 */

static void pcie_cap_slot_event(PCIDevice *dev, PCIExpressHotPlugEvent event)

{

    /* Minor optimization: if nothing changed - no event is needed. */

    if (pci_word_test_and_set_mask(dev->config + dev->exp.exp_cap +

                                   PCI_EXP_SLTSTA, event)) {

        return;

    }

    hotplug_event_notify(dev);

}

static int pcie_cap_slot_hotplug(DeviceState *qdev,

                                 PCIDevice *pci_dev, PCIHotplugState state)

{

    PCIDevice *d = PCI_DEVICE(qdev);

    uint8_t *exp_cap = d->config + d->exp.exp_cap;

    uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);

    /* 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 (state == PCI_COLDPLUG_ENABLED) {

        pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,

                                   PCI_EXP_SLTSTA_PDS);

        return 0;

    }

    PCIE_DEV_PRINTF(pci_dev, "hotplug state: %d\n", state);

    if (sltsta & PCI_EXP_SLTSTA_EIS) {

        /* the slot is electromechanically locked.

         * This error is propagated up to qdev and then to HMP/QMP.

         */

        return -EBUSY;

    }

    /* TODO: multifunction hot-plug.

     * Right now, only a device of function = 0 is allowed to be

     * hot plugged/unplugged.

     */

    assert(PCI_FUNC(pci_dev->devfn) == 0);

    if (state == PCI_HOTPLUG_ENABLED) {

        pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,

                                   PCI_EXP_SLTSTA_PDS);

        pcie_cap_slot_event(d, PCI_EXP_HP_EV_PDC);

    } else {

        qdev_free(&pci_dev->qdev);

        pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,

                                     PCI_EXP_SLTSTA_PDS);

        pcie_cap_slot_event(d, PCI_EXP_HP_EV_PDC);

    }

    return 0;

}

/* pci express slot for pci express root/downstream port

   PCI express capability slot registers */

void pcie_cap_slot_init(PCIDevice *dev, uint16_t slot)

{

    uint32_t pos = dev->exp.exp_cap;

    pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_FLAGS,

                               PCI_EXP_FLAGS_SLOT);

    pci_long_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCAP,

                                 ~PCI_EXP_SLTCAP_PSN);

    pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,

                               (slot << PCI_EXP_SLTCAP_PSN_SHIFT) |

                               PCI_EXP_SLTCAP_EIP |

                               PCI_EXP_SLTCAP_HPS |

                               PCI_EXP_SLTCAP_HPC |

                               PCI_EXP_SLTCAP_PIP |

                               PCI_EXP_SLTCAP_AIP |

                               PCI_EXP_SLTCAP_ABP);

    pci_word_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCTL,

                                 PCI_EXP_SLTCTL_PIC |

                                 PCI_EXP_SLTCTL_AIC);

    pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCTL,

                               PCI_EXP_SLTCTL_PIC_OFF |

                               PCI_EXP_SLTCTL_AIC_OFF);

    pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,

                               PCI_EXP_SLTCTL_PIC |

                               PCI_EXP_SLTCTL_AIC |

                               PCI_EXP_SLTCTL_HPIE |

                               PCI_EXP_SLTCTL_CCIE |

                               PCI_EXP_SLTCTL_PDCE |

                               PCI_EXP_SLTCTL_ABPE);

    /* Although reading PCI_EXP_SLTCTL_EIC returns always 0,

     * make the bit writable here in order to detect 1b is written.

     * pcie_cap_slot_write_config() test-and-clear the bit, so

     * this bit always returns 0 to the guest.

     */

    pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,

                               PCI_EXP_SLTCTL_EIC);

    pci_word_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_SLTSTA,

                               PCI_EXP_HP_EV_SUPPORTED);

    dev->exp.hpev_notified = false;

    pci_bus_hotplug(pci_bridge_get_sec_bus(DO_UPCAST(PCIBridge, dev, dev)),

                    pcie_cap_slot_hotplug, &dev->qdev);

}

void pcie_cap_slot_reset(PCIDevice *dev)

{

    uint8_t *exp_cap = dev->config + dev->exp.exp_cap;

    PCIE_DEV_PRINTF(dev, "reset\n");

    pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,

                                 PCI_EXP_SLTCTL_EIC |

                                 PCI_EXP_SLTCTL_PIC |

                                 PCI_EXP_SLTCTL_AIC |

                                 PCI_EXP_SLTCTL_HPIE |

                                 PCI_EXP_SLTCTL_CCIE |

                                 PCI_EXP_SLTCTL_PDCE |

                                 PCI_EXP_SLTCTL_ABPE);

    pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL,

                               PCI_EXP_SLTCTL_PIC_OFF |

                               PCI_EXP_SLTCTL_AIC_OFF);

    pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,

                                 PCI_EXP_SLTSTA_EIS |/* on reset,

                                                        the lock is released */

                                 PCI_EXP_SLTSTA_CC |

                                 PCI_EXP_SLTSTA_PDC |

                                 PCI_EXP_SLTSTA_ABP);

    hotplug_event_update_event_status(dev);

}

void pcie_cap_slot_write_config(PCIDevice *dev,

                                uint32_t addr, uint32_t val, int len)

{

    uint32_t pos = dev->exp.exp_cap;

    uint8_t *exp_cap = dev->config + pos;

    uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);

    if (ranges_overlap(addr, len, pos + PCI_EXP_SLTSTA, 2)) {

        hotplug_event_clear(dev);

    }

    if (!ranges_overlap(addr, len, pos + PCI_EXP_SLTCTL, 2)) {

        return;

    }

    if (pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,

                                     PCI_EXP_SLTCTL_EIC)) {

        sltsta ^= PCI_EXP_SLTSTA_EIS; /* toggle PCI_EXP_SLTSTA_EIS bit */

        pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);

        PCIE_DEV_PRINTF(dev, "PCI_EXP_SLTCTL_EIC: "

                        "sltsta -> 0x%02"PRIx16"\n",

                        sltsta);

    }

    hotplug_event_notify(dev);

    /* 

     * 6.7.3.2 Command Completed Events

     *

     * Software issues a command to a hot-plug capable Downstream Port by

     * issuing a write transaction that targets any portion of the Port’s Slot

     * Control register. A single write to the Slot Control register is

     * considered to be a single command, even if the write affects more than

     * one field in the Slot Control register. In response to this transaction,

     * the Port must carry out the requested actions and then set the

     * associated status field for the command completed event. */

    /* Real hardware might take a while to complete requested command because

     * physical movement would be involved like locking the electromechanical

     * lock.  However in our case, command is completed instantaneously above,

     * so send a command completion event right now.

     */

    pcie_cap_slot_event(dev, PCI_EXP_HP_EV_CCI);

}

int pcie_cap_slot_post_load(void *opaque, int version_id)

{

    PCIDevice *dev = opaque;

    hotplug_event_update_event_status(dev);

    return 0;

}

void pcie_cap_slot_push_attention_button(PCIDevice *dev)

{

    pcie_cap_slot_event(dev, PCI_EXP_HP_EV_ABP);

}

/* root control/capabilities/status. PME isn't emulated for now */

void pcie_cap_root_init(PCIDevice *dev)

{

    pci_set_word(dev->wmask + dev->exp.exp_cap + PCI_EXP_RTCTL,

                 PCI_EXP_RTCTL_SECEE | PCI_EXP_RTCTL_SENFEE |

                 PCI_EXP_RTCTL_SEFEE);

}

void pcie_cap_root_reset(PCIDevice *dev)

{

    pci_set_word(dev->config + dev->exp.exp_cap + PCI_EXP_RTCTL, 0);

}

/* function level reset(FLR) */

void pcie_cap_flr_init(PCIDevice *dev)

{

    pci_long_test_and_set_mask(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCAP,

                               PCI_EXP_DEVCAP_FLR);

    /* Although reading BCR_FLR returns always 0,

     * the bit is made writable here in order to detect the 1b is written

     * pcie_cap_flr_write_config() test-and-clear the bit, so

     * this bit always returns 0 to the guest.

     */

    pci_word_test_and_set_mask(dev->wmask + dev->exp.exp_cap + PCI_EXP_DEVCTL,

                               PCI_EXP_DEVCTL_BCR_FLR);

}

void pcie_cap_flr_write_config(PCIDevice *dev,

                               uint32_t addr, uint32_t val, int len)

{

    uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;

    if (pci_get_word(devctl) & PCI_EXP_DEVCTL_BCR_FLR) {

        /* Clear PCI_EXP_DEVCTL_BCR_FLR after invoking the reset handler

           so the handler can detect FLR by looking at this bit. */

        pci_device_reset(dev);

        pci_word_test_and_clear_mask(devctl, PCI_EXP_DEVCTL_BCR_FLR);

    }

}

/* Alternative Routing-ID Interpretation (ARI) */

/* ari forwarding support for down stream port */

void pcie_cap_ari_init(PCIDevice *dev)

{

    uint32_t pos = dev->exp.exp_cap;

    pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP2,

                               PCI_EXP_DEVCAP2_ARI);

    pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL2,

                               PCI_EXP_DEVCTL2_ARI);

}

void pcie_cap_ari_reset(PCIDevice *dev)

{

    uint8_t *devctl2 = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2;

    pci_long_test_and_clear_mask(devctl2, PCI_EXP_DEVCTL2_ARI);

}

bool pcie_cap_is_ari_enabled(const PCIDevice *dev)

{

    if (!pci_is_express(dev)) {

        return false;

    }

    if (!dev->exp.exp_cap) {

        return false;

    }

    return pci_get_long(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2) &

        PCI_EXP_DEVCTL2_ARI;

}

/**************************************************************************

 * pci express extended capability allocation functions

 * uint16_t ext_cap_id (16 bit)

 * uint8_t cap_ver (4 bit)

 * uint16_t cap_offset (12 bit)

 * uint16_t ext_cap_size

 */

static uint16_t pcie_find_capability_list(PCIDevice *dev, uint16_t cap_id,

                                          uint16_t *prev_p)

{

    uint16_t prev = 0;

    uint16_t next;

    uint32_t header = pci_get_long(dev->config + PCI_CONFIG_SPACE_SIZE);

    if (!header) {

        /* no extended capability */

        next = 0;

        goto out;

    }

    for (next = PCI_CONFIG_SPACE_SIZE; next;

         prev = next, next = PCI_EXT_CAP_NEXT(header)) {

        assert(next >= PCI_CONFIG_SPACE_SIZE);

        assert(next <= PCIE_CONFIG_SPACE_SIZE - 8);

        header = pci_get_long(dev->config + next);

        if (PCI_EXT_CAP_ID(header) == cap_id) {

            break;

        }

    }

out:

    if (prev_p) {

        *prev_p = prev;

    }

    return next;

}

uint16_t pcie_find_capability(PCIDevice *dev, uint16_t cap_id)

{

    return pcie_find_capability_list(dev, cap_id, NULL);

}

static void pcie_ext_cap_set_next(PCIDevice *dev, uint16_t pos, uint16_t next)

{

    uint16_t header = pci_get_long(dev->config + pos);

    assert(!(next & (PCI_EXT_CAP_ALIGN - 1)));

    header = (header & ~PCI_EXT_CAP_NEXT_MASK) |

        ((next << PCI_EXT_CAP_NEXT_SHIFT) & PCI_EXT_CAP_NEXT_MASK);

    pci_set_long(dev->config + pos, header);

}

/*

 * caller must supply valid (offset, size) * such that the range shouldn't

 * overlap with other capability or other registers.

 * This function doesn't check it.

 */

void pcie_add_capability(PCIDevice *dev,

                         uint16_t cap_id, uint8_t cap_ver,

                         uint16_t offset, uint16_t size)

{

    uint32_t header;

    uint16_t next;

    assert(offset >= PCI_CONFIG_SPACE_SIZE);

    assert(offset < offset + size);

    assert(offset + size < PCIE_CONFIG_SPACE_SIZE);

    assert(size >= 8);

    assert(pci_is_express(dev));

    if (offset == PCI_CONFIG_SPACE_SIZE) {

        header = pci_get_long(dev->config + offset);

        next = PCI_EXT_CAP_NEXT(header);

    } else {

        uint16_t prev;

        /* 0 is reserved cap id. use internally to find the last capability

           in the linked list */

        next = pcie_find_capability_list(dev, 0, &prev);

        assert(prev >= PCI_CONFIG_SPACE_SIZE);

        assert(next == 0);

        pcie_ext_cap_set_next(dev, prev, offset);

    }

    pci_set_long(dev->config + offset, PCI_EXT_CAP(cap_id, cap_ver, next));

    /* Make capability read-only by default */

    memset(dev->wmask + offset, 0, size);

    memset(dev->w1cmask + offset, 0, size);

    /* Check capability by default */

    memset(dev->cmask + offset, 0xFF, size);

}

/**************************************************************************

 * pci express extended capability helper functions

 */

/* ARI */

void pcie_ari_init(PCIDevice *dev, uint16_t offset, uint16_t nextfn)

{

    pcie_add_capability(dev, PCI_EXT_CAP_ID_ARI, PCI_ARI_VER,

                        offset, PCI_ARI_SIZEOF);

    pci_set_long(dev->config + offset + PCI_ARI_CAP, PCI_ARI_CAP_NFN(nextfn));

}