Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

[cris-mirror.git] / arch / powerpc / platforms / pseries / eeh_pseries.c

/*
 * The file intends to implement the platform dependent EEH operations on pseries.
 * Actually, the pseries platform is built based on RTAS heavily. That means the
 * pseries platform dependent EEH operations will be built on RTAS calls. The functions
 * are derived from arch/powerpc/platforms/pseries/eeh.c and necessary cleanup has
 * been done.
 *
 * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2011.
 * Copyright IBM Corporation 2001, 2005, 2006
 * Copyright Dave Engebretsen & Todd Inglett 2001
 * Copyright Linas Vepstas 2005, 2006
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/atomic.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/of.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <linux/rbtree.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>

#include <asm/eeh.h>
#include <asm/eeh_event.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
#include <asm/rtas.h>

/* RTAS tokens */
static int ibm_set_eeh_option;
static int ibm_set_slot_reset;
static int ibm_read_slot_reset_state;
static int ibm_read_slot_reset_state2;
static int ibm_slot_error_detail;
static int ibm_get_config_addr_info;
static int ibm_get_config_addr_info2;
static int ibm_configure_pe;

#ifdef CONFIG_PCI_IOV
void pseries_pcibios_bus_add_device(struct pci_dev *pdev)
{
        struct pci_dn *pdn = pci_get_pdn(pdev);
        struct pci_dn *physfn_pdn;
        struct eeh_dev *edev;

        if (!pdev->is_virtfn)
                return;

        pdn->device_id  =  pdev->device;
        pdn->vendor_id  =  pdev->vendor;
        pdn->class_code =  pdev->class;
        /*
         * Last allow unfreeze return code used for retrieval
         * by user space in eeh-sysfs to show the last command
         * completion from platform.
         */
        pdn->last_allow_rc =  0;
        physfn_pdn      =  pci_get_pdn(pdev->physfn);
        pdn->pe_number  =  physfn_pdn->pe_num_map[pdn->vf_index];
        edev = pdn_to_eeh_dev(pdn);

        /*
         * The following operations will fail if VF's sysfs files
         * aren't created or its resources aren't finalized.
         */
        eeh_add_device_early(pdn);
        eeh_add_device_late(pdev);
        edev->pe_config_addr =  (pdn->busno << 16) | (pdn->devfn << 8);
        eeh_rmv_from_parent_pe(edev); /* Remove as it is adding to bus pe */
        eeh_add_to_parent_pe(edev);   /* Add as VF PE type */
        eeh_sysfs_add_device(pdev);

}
#endif

/*
 * Buffer for reporting slot-error-detail rtas calls. Its here
 * in BSS, and not dynamically alloced, so that it ends up in
 * RMO where RTAS can access it.
 */
static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX];
static DEFINE_SPINLOCK(slot_errbuf_lock);
static int eeh_error_buf_size;

/**
 * pseries_eeh_init - EEH platform dependent initialization
 *
 * EEH platform dependent initialization on pseries.
 */
static int pseries_eeh_init(void)
{
        /* figure out EEH RTAS function call tokens */
        ibm_set_eeh_option              = rtas_token("ibm,set-eeh-option");
        ibm_set_slot_reset              = rtas_token("ibm,set-slot-reset");
        ibm_read_slot_reset_state2      = rtas_token("ibm,read-slot-reset-state2");
        ibm_read_slot_reset_state       = rtas_token("ibm,read-slot-reset-state");
        ibm_slot_error_detail           = rtas_token("ibm,slot-error-detail");
        ibm_get_config_addr_info2       = rtas_token("ibm,get-config-addr-info2");
        ibm_get_config_addr_info        = rtas_token("ibm,get-config-addr-info");
        ibm_configure_pe                = rtas_token("ibm,configure-pe");

        /*
         * ibm,configure-pe and ibm,configure-bridge have the same semantics,
         * however ibm,configure-pe can be faster.  If we can't find
         * ibm,configure-pe then fall back to using ibm,configure-bridge.
         */
        if (ibm_configure_pe == RTAS_UNKNOWN_SERVICE)
                ibm_configure_pe        = rtas_token("ibm,configure-bridge");

        /*
         * Necessary sanity check. We needn't check "get-config-addr-info"
         * and its variant since the old firmware probably support address
         * of domain/bus/slot/function for EEH RTAS operations.
         */
        if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE          ||
            ibm_set_slot_reset == RTAS_UNKNOWN_SERVICE          ||
            (ibm_read_slot_reset_state2 == RTAS_UNKNOWN_SERVICE &&
             ibm_read_slot_reset_state == RTAS_UNKNOWN_SERVICE) ||
            ibm_slot_error_detail == RTAS_UNKNOWN_SERVICE       ||
            ibm_configure_pe == RTAS_UNKNOWN_SERVICE) {
                pr_info("EEH functionality not supported\n");
                return -EINVAL;
        }

        /* Initialize error log lock and size */
        spin_lock_init(&slot_errbuf_lock);
        eeh_error_buf_size = rtas_token("rtas-error-log-max");
        if (eeh_error_buf_size == RTAS_UNKNOWN_SERVICE) {
                pr_info("%s: unknown EEH error log size\n",
                        __func__);
                eeh_error_buf_size = 1024;
        } else if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) {
                pr_info("%s: EEH error log size %d exceeds the maximal %d\n",
                        __func__, eeh_error_buf_size, RTAS_ERROR_LOG_MAX);
                eeh_error_buf_size = RTAS_ERROR_LOG_MAX;
        }

        /* Set EEH probe mode */
        eeh_add_flag(EEH_PROBE_MODE_DEVTREE | EEH_ENABLE_IO_FOR_LOG);

#ifdef CONFIG_PCI_IOV
        /* Set EEH machine dependent code */
        ppc_md.pcibios_bus_add_device = pseries_pcibios_bus_add_device;
#endif

        return 0;
}

static int pseries_eeh_cap_start(struct pci_dn *pdn)
{
        u32 status;

        if (!pdn)
                return 0;

        rtas_read_config(pdn, PCI_STATUS, 2, &status);
        if (!(status & PCI_STATUS_CAP_LIST))
                return 0;

        return PCI_CAPABILITY_LIST;
}


static int pseries_eeh_find_cap(struct pci_dn *pdn, int cap)
{
        int pos = pseries_eeh_cap_start(pdn);
        int cnt = 48;   /* Maximal number of capabilities */
        u32 id;

        if (!pos)
                return 0;

        while (cnt--) {
                rtas_read_config(pdn, pos, 1, &pos);
                if (pos < 0x40)
                        break;
                pos &= ~3;
                rtas_read_config(pdn, pos + PCI_CAP_LIST_ID, 1, &id);
                if (id == 0xff)
                        break;
                if (id == cap)
                        return pos;
                pos += PCI_CAP_LIST_NEXT;
        }

        return 0;
}

static int pseries_eeh_find_ecap(struct pci_dn *pdn, int cap)
{
        struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
        u32 header;
        int pos = 256;
        int ttl = (4096 - 256) / 8;

        if (!edev || !edev->pcie_cap)
                return 0;
        if (rtas_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
                return 0;
        else if (!header)
                return 0;

        while (ttl-- > 0) {
                if (PCI_EXT_CAP_ID(header) == cap && pos)
                        return pos;

                pos = PCI_EXT_CAP_NEXT(header);
                if (pos < 256)
                        break;

                if (rtas_read_config(pdn, pos, 4, &header) != PCIBIOS_SUCCESSFUL)
                        break;
        }

        return 0;
}

/**
 * pseries_eeh_probe - EEH probe on the given device
 * @pdn: PCI device node
 * @data: Unused
 *
 * When EEH module is installed during system boot, all PCI devices
 * are checked one by one to see if it supports EEH. The function
 * is introduced for the purpose.
 */
static void *pseries_eeh_probe(struct pci_dn *pdn, void *data)
{
        struct eeh_dev *edev;
        struct eeh_pe pe;
        u32 pcie_flags;
        int enable = 0;
        int ret;

        /* Retrieve OF node and eeh device */
        edev = pdn_to_eeh_dev(pdn);
        if (!edev || edev->pe)
                return NULL;

        /* Check class/vendor/device IDs */
        if (!pdn->vendor_id || !pdn->device_id || !pdn->class_code)
                return NULL;

        /* Skip for PCI-ISA bridge */
        if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_ISA)
                return NULL;

        /*
         * Update class code and mode of eeh device. We need
         * correctly reflects that current device is root port
         * or PCIe switch downstream port.
         */
        edev->class_code = pdn->class_code;
        edev->pcix_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
        edev->pcie_cap = pseries_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
        edev->aer_cap = pseries_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
        edev->mode &= 0xFFFFFF00;
        if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
                edev->mode |= EEH_DEV_BRIDGE;
                if (edev->pcie_cap) {
                        rtas_read_config(pdn, edev->pcie_cap + PCI_EXP_FLAGS,
                                         2, &pcie_flags);
                        pcie_flags = (pcie_flags & PCI_EXP_FLAGS_TYPE) >> 4;
                        if (pcie_flags == PCI_EXP_TYPE_ROOT_PORT)
                                edev->mode |= EEH_DEV_ROOT_PORT;
                        else if (pcie_flags == PCI_EXP_TYPE_DOWNSTREAM)
                                edev->mode |= EEH_DEV_DS_PORT;
                }
        }

        /* Initialize the fake PE */
        memset(&pe, 0, sizeof(struct eeh_pe));
        pe.phb = pdn->phb;
        pe.config_addr = (pdn->busno << 16) | (pdn->devfn << 8);

        /* Enable EEH on the device */
        ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
        if (!ret) {
                /* Retrieve PE address */
                edev->pe_config_addr = eeh_ops->get_pe_addr(&pe);
                pe.addr = edev->pe_config_addr;

                /* Some older systems (Power4) allow the ibm,set-eeh-option
                 * call to succeed even on nodes where EEH is not supported.
                 * Verify support explicitly.
                 */
                ret = eeh_ops->get_state(&pe, NULL);
                if (ret > 0 && ret != EEH_STATE_NOT_SUPPORT)
                        enable = 1;

                if (enable) {
                        eeh_add_flag(EEH_ENABLED);
                        eeh_add_to_parent_pe(edev);

                        pr_debug("%s: EEH enabled on %02x:%02x.%01x PHB#%x-PE#%x\n",
                                __func__, pdn->busno, PCI_SLOT(pdn->devfn),
                                PCI_FUNC(pdn->devfn), pe.phb->global_number,
                                pe.addr);
                } else if (pdn->parent && pdn_to_eeh_dev(pdn->parent) &&
                           (pdn_to_eeh_dev(pdn->parent))->pe) {
                        /* This device doesn't support EEH, but it may have an
                         * EEH parent, in which case we mark it as supported.
                         */
                        edev->pe_config_addr = pdn_to_eeh_dev(pdn->parent)->pe_config_addr;
                        eeh_add_to_parent_pe(edev);
                }
        }

        /* Save memory bars */
        eeh_save_bars(edev);

        return NULL;
}

/**
 * pseries_eeh_set_option - Initialize EEH or MMIO/DMA reenable
 * @pe: EEH PE
 * @option: operation to be issued
 *
 * The function is used to control the EEH functionality globally.
 * Currently, following options are support according to PAPR:
 * Enable EEH, Disable EEH, Enable MMIO and Enable DMA
 */
static int pseries_eeh_set_option(struct eeh_pe *pe, int option)
{
        int ret = 0;
        int config_addr;

        /*
         * When we're enabling or disabling EEH functioality on
         * the particular PE, the PE config address is possibly
         * unavailable. Therefore, we have to figure it out from
         * the FDT node.
         */
        switch (option) {
        case EEH_OPT_DISABLE:
        case EEH_OPT_ENABLE:
        case EEH_OPT_THAW_MMIO:
        case EEH_OPT_THAW_DMA:
                config_addr = pe->config_addr;
                if (pe->addr)
                        config_addr = pe->addr;
                break;
        case EEH_OPT_FREEZE_PE:
                /* Not support */
                return 0;
        default:
                pr_err("%s: Invalid option %d\n",
                        __func__, option);
                return -EINVAL;
        }

        ret = rtas_call(ibm_set_eeh_option, 4, 1, NULL,
                        config_addr, BUID_HI(pe->phb->buid),
                        BUID_LO(pe->phb->buid), option);

        return ret;
}

/**
 * pseries_eeh_get_pe_addr - Retrieve PE address
 * @pe: EEH PE
 *
 * Retrieve the assocated PE address. Actually, there're 2 RTAS
 * function calls dedicated for the purpose. We need implement
 * it through the new function and then the old one. Besides,
 * you should make sure the config address is figured out from
 * FDT node before calling the function.
 *
 * It's notable that zero'ed return value means invalid PE config
 * address.
 */
static int pseries_eeh_get_pe_addr(struct eeh_pe *pe)
{
        int ret = 0;
        int rets[3];

        if (ibm_get_config_addr_info2 != RTAS_UNKNOWN_SERVICE) {
                /*
                 * First of all, we need to make sure there has one PE
                 * associated with the device. Otherwise, PE address is
                 * meaningless.
                 */
                ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
                                pe->config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid), 1);
                if (ret || (rets[0] == 0))
                        return 0;

                /* Retrieve the associated PE config address */
                ret = rtas_call(ibm_get_config_addr_info2, 4, 2, rets,
                                pe->config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid), 0);
                if (ret) {
                        pr_warn("%s: Failed to get address for PHB#%x-PE#%x\n",
                                __func__, pe->phb->global_number, pe->config_addr);
                        return 0;
                }

                return rets[0];
        }

        if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) {
                ret = rtas_call(ibm_get_config_addr_info, 4, 2, rets,
                                pe->config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid), 0);
                if (ret) {
                        pr_warn("%s: Failed to get address for PHB#%x-PE#%x\n",
                                __func__, pe->phb->global_number, pe->config_addr);
                        return 0;
                }

                return rets[0];
        }

        return ret;
}

/**
 * pseries_eeh_get_state - Retrieve PE state
 * @pe: EEH PE
 * @state: return value
 *
 * Retrieve the state of the specified PE. On RTAS compliant
 * pseries platform, there already has one dedicated RTAS function
 * for the purpose. It's notable that the associated PE config address
 * might be ready when calling the function. Therefore, endeavour to
 * use the PE config address if possible. Further more, there're 2
 * RTAS calls for the purpose, we need to try the new one and back
 * to the old one if the new one couldn't work properly.
 */
static int pseries_eeh_get_state(struct eeh_pe *pe, int *state)
{
        int config_addr;
        int ret;
        int rets[4];
        int result;

        /* Figure out PE config address if possible */
        config_addr = pe->config_addr;
        if (pe->addr)
                config_addr = pe->addr;

        if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) {
                ret = rtas_call(ibm_read_slot_reset_state2, 3, 4, rets,
                                config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid));
        } else if (ibm_read_slot_reset_state != RTAS_UNKNOWN_SERVICE) {
                /* Fake PE unavailable info */
                rets[2] = 0;
                ret = rtas_call(ibm_read_slot_reset_state, 3, 3, rets,
                                config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid));
        } else {
                return EEH_STATE_NOT_SUPPORT;
        }

        if (ret)
                return ret;

        /* Parse the result out */
        if (!rets[1])
                return EEH_STATE_NOT_SUPPORT;

        switch(rets[0]) {
        case 0:
                result = EEH_STATE_MMIO_ACTIVE |
                         EEH_STATE_DMA_ACTIVE;
                break;
        case 1:
                result = EEH_STATE_RESET_ACTIVE |
                         EEH_STATE_MMIO_ACTIVE  |
                         EEH_STATE_DMA_ACTIVE;
                break;
        case 2:
                result = 0;
                break;
        case 4:
                result = EEH_STATE_MMIO_ENABLED;
                break;
        case 5:
                if (rets[2]) {
                        if (state) *state = rets[2];
                        result = EEH_STATE_UNAVAILABLE;
                } else {
                        result = EEH_STATE_NOT_SUPPORT;
                }
                break;
        default:
                result = EEH_STATE_NOT_SUPPORT;
        }

        return result;
}

/**
 * pseries_eeh_reset - Reset the specified PE
 * @pe: EEH PE
 * @option: reset option
 *
 * Reset the specified PE
 */
static int pseries_eeh_reset(struct eeh_pe *pe, int option)
{
        int config_addr;
        int ret;

        /* Figure out PE address */
        config_addr = pe->config_addr;
        if (pe->addr)
                config_addr = pe->addr;

        /* Reset PE through RTAS call */
        ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
                        config_addr, BUID_HI(pe->phb->buid),
                        BUID_LO(pe->phb->buid), option);

        /* If fundamental-reset not supported, try hot-reset */
        if (option == EEH_RESET_FUNDAMENTAL &&
            ret == -8) {
                option = EEH_RESET_HOT;
                ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
                                config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid), option);
        }

        /* We need reset hold or settlement delay */
        if (option == EEH_RESET_FUNDAMENTAL ||
            option == EEH_RESET_HOT)
                msleep(EEH_PE_RST_HOLD_TIME);
        else
                msleep(EEH_PE_RST_SETTLE_TIME);

        return ret;
}

/**
 * pseries_eeh_wait_state - Wait for PE state
 * @pe: EEH PE
 * @max_wait: maximal period in millisecond
 *
 * Wait for the state of associated PE. It might take some time
 * to retrieve the PE's state.
 */
static int pseries_eeh_wait_state(struct eeh_pe *pe, int max_wait)
{
        int ret;
        int mwait;

        /*
         * According to PAPR, the state of PE might be temporarily
         * unavailable. Under the circumstance, we have to wait
         * for indicated time determined by firmware. The maximal
         * wait time is 5 minutes, which is acquired from the original
         * EEH implementation. Also, the original implementation
         * also defined the minimal wait time as 1 second.
         */
#define EEH_STATE_MIN_WAIT_TIME (1000)
#define EEH_STATE_MAX_WAIT_TIME (300 * 1000)

        while (1) {
                ret = pseries_eeh_get_state(pe, &mwait);

                /*
                 * If the PE's state is temporarily unavailable,
                 * we have to wait for the specified time. Otherwise,
                 * the PE's state will be returned immediately.
                 */
                if (ret != EEH_STATE_UNAVAILABLE)
                        return ret;

                if (max_wait <= 0) {
                        pr_warn("%s: Timeout when getting PE's state (%d)\n",
                                __func__, max_wait);
                        return EEH_STATE_NOT_SUPPORT;
                }

                if (mwait <= 0) {
                        pr_warn("%s: Firmware returned bad wait value %d\n",
                                __func__, mwait);
                        mwait = EEH_STATE_MIN_WAIT_TIME;
                } else if (mwait > EEH_STATE_MAX_WAIT_TIME) {
                        pr_warn("%s: Firmware returned too long wait value %d\n",
                                __func__, mwait);
                        mwait = EEH_STATE_MAX_WAIT_TIME;
                }

                max_wait -= mwait;
                msleep(mwait);
        }

        return EEH_STATE_NOT_SUPPORT;
}

/**
 * pseries_eeh_get_log - Retrieve error log
 * @pe: EEH PE
 * @severity: temporary or permanent error log
 * @drv_log: driver log to be combined with retrieved error log
 * @len: length of driver log
 *
 * Retrieve the temporary or permanent error from the PE.
 * Actually, the error will be retrieved through the dedicated
 * RTAS call.
 */
static int pseries_eeh_get_log(struct eeh_pe *pe, int severity, char *drv_log, unsigned long len)
{
        int config_addr;
        unsigned long flags;
        int ret;

        spin_lock_irqsave(&slot_errbuf_lock, flags);
        memset(slot_errbuf, 0, eeh_error_buf_size);

        /* Figure out the PE address */
        config_addr = pe->config_addr;
        if (pe->addr)
                config_addr = pe->addr;

        ret = rtas_call(ibm_slot_error_detail, 8, 1, NULL, config_addr,
                        BUID_HI(pe->phb->buid), BUID_LO(pe->phb->buid),
                        virt_to_phys(drv_log), len,
                        virt_to_phys(slot_errbuf), eeh_error_buf_size,
                        severity);
        if (!ret)
                log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
        spin_unlock_irqrestore(&slot_errbuf_lock, flags);

        return ret;
}

/**
 * pseries_eeh_configure_bridge - Configure PCI bridges in the indicated PE
 * @pe: EEH PE
 *
 * The function will be called to reconfigure the bridges included
 * in the specified PE so that the mulfunctional PE would be recovered
 * again.
 */
static int pseries_eeh_configure_bridge(struct eeh_pe *pe)
{
        int config_addr;
        int ret;
        /* Waiting 0.2s maximum before skipping configuration */
        int max_wait = 200;

        /* Figure out the PE address */
        config_addr = pe->config_addr;
        if (pe->addr)
                config_addr = pe->addr;

        while (max_wait > 0) {
                ret = rtas_call(ibm_configure_pe, 3, 1, NULL,
                                config_addr, BUID_HI(pe->phb->buid),
                                BUID_LO(pe->phb->buid));

                if (!ret)
                        return ret;

                /*
                 * If RTAS returns a delay value that's above 100ms, cut it
                 * down to 100ms in case firmware made a mistake.  For more
                 * on how these delay values work see rtas_busy_delay_time
                 */
                if (ret > RTAS_EXTENDED_DELAY_MIN+2 &&
                    ret <= RTAS_EXTENDED_DELAY_MAX)
                        ret = RTAS_EXTENDED_DELAY_MIN+2;

                max_wait -= rtas_busy_delay_time(ret);

                if (max_wait < 0)
                        break;

                rtas_busy_delay(ret);
        }

        pr_warn("%s: Unable to configure bridge PHB#%x-PE#%x (%d)\n",
                __func__, pe->phb->global_number, pe->addr, ret);
        return ret;
}

/**
 * pseries_eeh_read_config - Read PCI config space
 * @pdn: PCI device node
 * @where: PCI address
 * @size: size to read
 * @val: return value
 *
 * Read config space from the speicifed device
 */
static int pseries_eeh_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
{
        return rtas_read_config(pdn, where, size, val);
}

/**
 * pseries_eeh_write_config - Write PCI config space
 * @pdn: PCI device node
 * @where: PCI address
 * @size: size to write
 * @val: value to be written
 *
 * Write config space to the specified device
 */
static int pseries_eeh_write_config(struct pci_dn *pdn, int where, int size, u32 val)
{
        return rtas_write_config(pdn, where, size, val);
}

static int pseries_eeh_restore_config(struct pci_dn *pdn)
{
        struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
        s64 ret = 0;

        if (!edev)
                return -EEXIST;

        /*
         * FIXME: The MPS, error routing rules, timeout setting are worthy
         * to be exported by firmware in extendible way.
         */
        if (edev->physfn)
                ret = eeh_restore_vf_config(pdn);

        if (ret) {
                pr_warn("%s: Can't reinit PCI dev 0x%x (%lld)\n",
                        __func__, edev->pe_config_addr, ret);
                return -EIO;
        }

        return ret;
}

#ifdef CONFIG_PCI_IOV
int pseries_send_allow_unfreeze(struct pci_dn *pdn,
                                u16 *vf_pe_array, int cur_vfs)
{
        int rc;
        int ibm_allow_unfreeze = rtas_token("ibm,open-sriov-allow-unfreeze");
        unsigned long buid, addr;

        addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
        buid = pdn->phb->buid;
        spin_lock(&rtas_data_buf_lock);
        memcpy(rtas_data_buf, vf_pe_array, RTAS_DATA_BUF_SIZE);
        rc = rtas_call(ibm_allow_unfreeze, 5, 1, NULL,
                       addr,
                       BUID_HI(buid),
                       BUID_LO(buid),
                       rtas_data_buf, cur_vfs * sizeof(u16));
        spin_unlock(&rtas_data_buf_lock);
        if (rc)
                pr_warn("%s: Failed to allow unfreeze for PHB#%x-PE#%lx, rc=%x\n",
                        __func__,
                        pdn->phb->global_number, addr, rc);
        return rc;
}

static int pseries_call_allow_unfreeze(struct eeh_dev *edev)
{
        struct pci_dn *pdn, *tmp, *parent, *physfn_pdn;
        int cur_vfs = 0, rc = 0, vf_index, bus, devfn;
        u16 *vf_pe_array;

        vf_pe_array = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
        if (!vf_pe_array)
                return -ENOMEM;
        if (pci_num_vf(edev->physfn ? edev->physfn : edev->pdev)) {
                if (edev->pdev->is_physfn) {
                        cur_vfs = pci_num_vf(edev->pdev);
                        pdn = eeh_dev_to_pdn(edev);
                        parent = pdn->parent;
                        for (vf_index = 0; vf_index < cur_vfs; vf_index++)
                                vf_pe_array[vf_index] =
                                        cpu_to_be16(pdn->pe_num_map[vf_index]);
                        rc = pseries_send_allow_unfreeze(pdn, vf_pe_array,
                                                         cur_vfs);
                        pdn->last_allow_rc = rc;
                        for (vf_index = 0; vf_index < cur_vfs; vf_index++) {
                                list_for_each_entry_safe(pdn, tmp,
                                                         &parent->child_list,
                                                         list) {
                                        bus = pci_iov_virtfn_bus(edev->pdev,
                                                                 vf_index);
                                        devfn = pci_iov_virtfn_devfn(edev->pdev,
                                                                     vf_index);
                                        if (pdn->busno != bus ||
                                            pdn->devfn != devfn)
                                                continue;
                                        pdn->last_allow_rc = rc;
                                }
                        }
                } else {
                        pdn = pci_get_pdn(edev->pdev);
                        vf_pe_array[0] = cpu_to_be16(pdn->pe_number);
                        physfn_pdn = pci_get_pdn(edev->physfn);
                        rc = pseries_send_allow_unfreeze(physfn_pdn,
                                                         vf_pe_array, 1);
                        pdn->last_allow_rc = rc;
                }
        }

        kfree(vf_pe_array);
        return rc;
}

static int pseries_notify_resume(struct pci_dn *pdn)
{
        struct eeh_dev *edev = pdn_to_eeh_dev(pdn);

        if (!edev)
                return -EEXIST;

        if (rtas_token("ibm,open-sriov-allow-unfreeze")
            == RTAS_UNKNOWN_SERVICE)
                return -EINVAL;

        if (edev->pdev->is_physfn || edev->pdev->is_virtfn)
                return pseries_call_allow_unfreeze(edev);

        return 0;
}
#endif

static struct eeh_ops pseries_eeh_ops = {
        .name                   = "pseries",
        .init                   = pseries_eeh_init,
        .probe                  = pseries_eeh_probe,
        .set_option             = pseries_eeh_set_option,
        .get_pe_addr            = pseries_eeh_get_pe_addr,
        .get_state              = pseries_eeh_get_state,
        .reset                  = pseries_eeh_reset,
        .wait_state             = pseries_eeh_wait_state,
        .get_log                = pseries_eeh_get_log,
        .configure_bridge       = pseries_eeh_configure_bridge,
        .err_inject             = NULL,
        .read_config            = pseries_eeh_read_config,
        .write_config           = pseries_eeh_write_config,
        .next_error             = NULL,
        .restore_config         = pseries_eeh_restore_config,
#ifdef CONFIG_PCI_IOV
        .notify_resume          = pseries_notify_resume
#endif
};

/**
 * eeh_pseries_init - Register platform dependent EEH operations
 *
 * EEH initialization on pseries platform. This function should be
 * called before any EEH related functions.
 */
static int __init eeh_pseries_init(void)
{
        int ret;

        ret = eeh_ops_register(&pseries_eeh_ops);
        if (!ret)
                pr_info("EEH: pSeries platform initialized\n");
        else
                pr_info("EEH: pSeries platform initialization failure (%d)\n",
                        ret);

        return ret;
}
machine_early_initcall(pseries, eeh_pseries_init);