arch/powerpc/platforms/pseries/eeh_pseries.c - kernel/msm-4.9 - Gitiles

 /*
  * 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 devired 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_bridge;
 static int ibm_configure_pe;

 /*
  * 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_bridge		= rtas_token("ibm,configure-bridge");

 	/* necessary sanity check */
 	if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,set-eeh-option> invalid\n",
 			__func__);
 		return -EINVAL;
 	} else if (ibm_set_slot_reset == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,set-slot-reset> invalid\n",
 			__func__);
 		return -EINVAL;
 	} else if (ibm_read_slot_reset_state2 == RTAS_UNKNOWN_SERVICE &&
 		   ibm_read_slot_reset_state == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,read-slot-reset-state2> and "
 			"<ibm,read-slot-reset-state> invalid\n",
 			__func__);
 		return -EINVAL;
 	} else if (ibm_slot_error_detail == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,slot-error-detail> invalid\n",
 			__func__);
 		return -EINVAL;
 	} else if (ibm_get_config_addr_info2 == RTAS_UNKNOWN_SERVICE &&
 		   ibm_get_config_addr_info == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,get-config-addr-info2> and "
 			"<ibm,get-config-addr-info> invalid\n",
 			__func__);
 		return -EINVAL;
 	} else if (ibm_configure_pe == RTAS_UNKNOWN_SERVICE &&
 		   ibm_configure_bridge == RTAS_UNKNOWN_SERVICE) {
 		pr_warning("%s: RTAS service <ibm,configure-pe> and "
 			"<ibm,configure-bridge> invalid\n",
 			__func__);
 		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_warning("%s: unknown EEH error log size\n",
 			__func__);
 		eeh_error_buf_size = 1024;
 	} else if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) {
 		pr_warning("%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_probe_mode_set(EEH_PROBE_MODE_DEVTREE);

 	return 0;
 }

 /**
  * pseries_eeh_of_probe - EEH probe on the given device
  * @dn: OF node
  * @flag: 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_of_probe(struct device_node *dn, void *flag)
 {
 	struct eeh_dev *edev;
 	struct eeh_pe pe;
 	const u32 *class_code, *vendor_id, *device_id;
 	const u32 *regs;
 	int enable = 0;
 	int ret;

 	/* Retrieve OF node and eeh device */
 	edev = of_node_to_eeh_dev(dn);
 	if (!of_device_is_available(dn))
 		return NULL;

 	/* Retrieve class/vendor/device IDs */
 	class_code = of_get_property(dn, "class-code", NULL);
 	vendor_id  = of_get_property(dn, "vendor-id", NULL);
 	device_id  = of_get_property(dn, "device-id", NULL);

 	/* Skip for bad OF node or PCI-ISA bridge */
 	if (!class_code || !vendor_id || !device_id)
 		return NULL;
 	if (dn->type && !strcmp(dn->type, "isa"))
 		return NULL;

 	/* Update class code and mode of eeh device */
 	edev->class_code = *class_code;
 	edev->mode = 0;

 	/* Retrieve the device address */
 	regs = of_get_property(dn, "reg", NULL);
 	if (!regs) {
 		pr_warning("%s: OF node property %s::reg not found\n",
 			__func__, dn->full_name);
 		return NULL;
 	}

 	/* Initialize the fake PE */
 	memset(&pe, 0, sizeof(struct eeh_pe));
 	pe.phb = edev->phb;
 	pe.config_addr = regs[0];

 	/* Enable EEH on the device */
 	ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
 	if (!ret) {
 		edev->config_addr = regs[0];
 		/* 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_subsystem_enabled = 1;
 			eeh_add_to_parent_pe(edev);

 			pr_debug("%s: EEH enabled on %s PHB#%d-PE#%x, config addr#%x\n",
 				__func__, dn->full_name, pe.phb->global_number,
 				pe.addr, pe.config_addr);
 		} else if (dn->parent && of_node_to_eeh_dev(dn->parent) &&
 			   (of_node_to_eeh_dev(dn->parent))->pe) {
 			/* This device doesn't support EEH, but it may have an
 			 * EEH parent, in which case we mark it as supported.
 			 */
 			edev->config_addr = of_node_to_eeh_dev(dn->parent)->config_addr;
 			edev->pe_config_addr = of_node_to_eeh_dev(dn->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;

 	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_warning("%s: Failed to get address for PHB#%d-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_warning("%s: Failed to get address for PHB#%d-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 */
 	result = 0;
 	if (rets[1]) {
 		switch(rets[0]) {
 		case 0:
 			result &= ~EEH_STATE_RESET_ACTIVE;
 			result |= EEH_STATE_MMIO_ACTIVE;
 			result |= EEH_STATE_DMA_ACTIVE;
 			break;
 		case 1:
 			result |= EEH_STATE_RESET_ACTIVE;
 			result |= EEH_STATE_MMIO_ACTIVE;
 			result |= EEH_STATE_DMA_ACTIVE;
 			break;
 		case 2:
 			result &= ~EEH_STATE_RESET_ACTIVE;
 			result &= ~EEH_STATE_MMIO_ACTIVE;
 			result &= ~EEH_STATE_DMA_ACTIVE;
 			break;
 		case 4:
 			result &= ~EEH_STATE_RESET_ACTIVE;
 			result &= ~EEH_STATE_MMIO_ACTIVE;
 			result &= ~EEH_STATE_DMA_ACTIVE;
 			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;
 			}
 		default:
 			result = EEH_STATE_NOT_SUPPORT;
 		}
 	} else {
 		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) {
 		ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
 				config_addr, BUID_HI(pe->phb->buid),
 				BUID_LO(pe->phb->buid), EEH_RESET_HOT);
 	}

 	return ret;
 }

 /**
  * pseries_eeh_wait_state - Wait for PE state
  * @pe: EEH PE
  * @max_wait: maximal period in microsecond
  *
  * 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_warning("%s: Timeout when getting PE's state (%d)\n",
 				__func__, max_wait);
 			return EEH_STATE_NOT_SUPPORT;
 		}

 		if (mwait <= 0) {
 			pr_warning("%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_warning("%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;

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

 	/* Use new configure-pe function, if supported */
 	if (ibm_configure_pe != RTAS_UNKNOWN_SERVICE) {
 		ret = rtas_call(ibm_configure_pe, 3, 1, NULL,
 				config_addr, BUID_HI(pe->phb->buid),
 				BUID_LO(pe->phb->buid));
 	} else if (ibm_configure_bridge != RTAS_UNKNOWN_SERVICE) {
 		ret = rtas_call(ibm_configure_bridge, 3, 1, NULL,
 				config_addr, BUID_HI(pe->phb->buid),
 				BUID_LO(pe->phb->buid));
 	} else {
 		return -EFAULT;
 	}

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

 	return ret;
 }

 /**
  * pseries_eeh_read_config - Read PCI config space
  * @dn: 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 device_node *dn, int where, int size, u32 *val)
 {
 	struct pci_dn *pdn;

 	pdn = PCI_DN(dn);

 	return rtas_read_config(pdn, where, size, val);
 }

 /**
  * pseries_eeh_write_config - Write PCI config space
  * @dn: 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 device_node *dn, int where, int size, u32 val)
 {
 	struct pci_dn *pdn;

 	pdn = PCI_DN(dn);

 	return rtas_write_config(pdn, where, size, val);
 }

 static struct eeh_ops pseries_eeh_ops = {
 	.name			= "pseries",
 	.init			= pseries_eeh_init,
 	.of_probe		= pseries_eeh_of_probe,
 	.dev_probe		= NULL,
 	.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,
 	.read_config		= pseries_eeh_read_config,
 	.write_config		= pseries_eeh_write_config
 };

 /**
  * 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 = -EINVAL;

 	if (!machine_is(pseries))
 		return 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;
 }

 early_initcall(eeh_pseries_init);
	/*
	* 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 devired 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_bridge;
	static int ibm_configure_pe;

	/*
	* 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_bridge = rtas_token("ibm,configure-bridge");

	/* necessary sanity check */
	if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,set-eeh-option> invalid\n",
	__func__);
	return -EINVAL;
	} else if (ibm_set_slot_reset == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,set-slot-reset> invalid\n",
	__func__);
	return -EINVAL;
	} else if (ibm_read_slot_reset_state2 == RTAS_UNKNOWN_SERVICE &&
	ibm_read_slot_reset_state == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,read-slot-reset-state2> and "
	"<ibm,read-slot-reset-state> invalid\n",
	__func__);
	return -EINVAL;
	} else if (ibm_slot_error_detail == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,slot-error-detail> invalid\n",
	__func__);
	return -EINVAL;
	} else if (ibm_get_config_addr_info2 == RTAS_UNKNOWN_SERVICE &&
	ibm_get_config_addr_info == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,get-config-addr-info2> and "
	"<ibm,get-config-addr-info> invalid\n",
	__func__);
	return -EINVAL;
	} else if (ibm_configure_pe == RTAS_UNKNOWN_SERVICE &&
	ibm_configure_bridge == RTAS_UNKNOWN_SERVICE) {
	pr_warning("%s: RTAS service <ibm,configure-pe> and "
	"<ibm,configure-bridge> invalid\n",
	__func__);
	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_warning("%s: unknown EEH error log size\n",
	__func__);
	eeh_error_buf_size = 1024;
	} else if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) {
	pr_warning("%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_probe_mode_set(EEH_PROBE_MODE_DEVTREE);

	return 0;
	}

	/**
	* pseries_eeh_of_probe - EEH probe on the given device
	* @dn: OF node
	* @flag: 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_of_probe(struct device_node dn, void *flag)
	{
	struct eeh_dev *edev;
	struct eeh_pe pe;
	const u32 class_code, vendor_id, *device_id;
	const u32 *regs;
	int enable = 0;
	int ret;

	/* Retrieve OF node and eeh device */
	edev = of_node_to_eeh_dev(dn);
	if (!of_device_is_available(dn))
	return NULL;

	/* Retrieve class/vendor/device IDs */
	class_code = of_get_property(dn, "class-code", NULL);
	vendor_id = of_get_property(dn, "vendor-id", NULL);
	device_id = of_get_property(dn, "device-id", NULL);

	/* Skip for bad OF node or PCI-ISA bridge */
	if (!class_code \|\| !vendor_id \|\| !device_id)
	return NULL;
	if (dn->type && !strcmp(dn->type, "isa"))
	return NULL;

	/* Update class code and mode of eeh device */
	edev->class_code = *class_code;
	edev->mode = 0;

	/* Retrieve the device address */
	regs = of_get_property(dn, "reg", NULL);
	if (!regs) {
	pr_warning("%s: OF node property %s::reg not found\n",
	__func__, dn->full_name);
	return NULL;
	}

	/* Initialize the fake PE */
	memset(&pe, 0, sizeof(struct eeh_pe));
	pe.phb = edev->phb;
	pe.config_addr = regs[0];

	/* Enable EEH on the device */
	ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
	if (!ret) {
	edev->config_addr = regs[0];
	/* 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_subsystem_enabled = 1;
	eeh_add_to_parent_pe(edev);

	pr_debug("%s: EEH enabled on %s PHB#%d-PE#%x, config addr#%x\n",
	__func__, dn->full_name, pe.phb->global_number,
	pe.addr, pe.config_addr);
	} else if (dn->parent && of_node_to_eeh_dev(dn->parent) &&
	(of_node_to_eeh_dev(dn->parent))->pe) {
	/* This device doesn't support EEH, but it may have an
	* EEH parent, in which case we mark it as supported.
	*/
	edev->config_addr = of_node_to_eeh_dev(dn->parent)->config_addr;
	edev->pe_config_addr = of_node_to_eeh_dev(dn->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;

	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_warning("%s: Failed to get address for PHB#%d-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_warning("%s: Failed to get address for PHB#%d-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 */
	result = 0;
	if (rets[1]) {
	switch(rets[0]) {
	case 0:
	result &= ~EEH_STATE_RESET_ACTIVE;
	result \|= EEH_STATE_MMIO_ACTIVE;
	result \|= EEH_STATE_DMA_ACTIVE;
	break;
	case 1:
	result \|= EEH_STATE_RESET_ACTIVE;
	result \|= EEH_STATE_MMIO_ACTIVE;
	result \|= EEH_STATE_DMA_ACTIVE;
	break;
	case 2:
	result &= ~EEH_STATE_RESET_ACTIVE;
	result &= ~EEH_STATE_MMIO_ACTIVE;
	result &= ~EEH_STATE_DMA_ACTIVE;
	break;
	case 4:
	result &= ~EEH_STATE_RESET_ACTIVE;
	result &= ~EEH_STATE_MMIO_ACTIVE;
	result &= ~EEH_STATE_DMA_ACTIVE;
	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;
	}
	default:
	result = EEH_STATE_NOT_SUPPORT;
	}
	} else {
	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) {
	ret = rtas_call(ibm_set_slot_reset, 4, 1, NULL,
	config_addr, BUID_HI(pe->phb->buid),
	BUID_LO(pe->phb->buid), EEH_RESET_HOT);
	}

	return ret;
	}

	/**
	* pseries_eeh_wait_state - Wait for PE state
	* @pe: EEH PE
	* @max_wait: maximal period in microsecond
	*
	* 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_warning("%s: Timeout when getting PE's state (%d)\n",
	__func__, max_wait);
	return EEH_STATE_NOT_SUPPORT;
	}

	if (mwait <= 0) {
	pr_warning("%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_warning("%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;

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

	/* Use new configure-pe function, if supported */
	if (ibm_configure_pe != RTAS_UNKNOWN_SERVICE) {
	ret = rtas_call(ibm_configure_pe, 3, 1, NULL,
	config_addr, BUID_HI(pe->phb->buid),
	BUID_LO(pe->phb->buid));
	} else if (ibm_configure_bridge != RTAS_UNKNOWN_SERVICE) {
	ret = rtas_call(ibm_configure_bridge, 3, 1, NULL,
	config_addr, BUID_HI(pe->phb->buid),
	BUID_LO(pe->phb->buid));
	} else {
	return -EFAULT;
	}

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

	return ret;
	}

	/**
	* pseries_eeh_read_config - Read PCI config space
	* @dn: 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 device_node dn, int where, int size, u32 val)
	{
	struct pci_dn *pdn;

	pdn = PCI_DN(dn);

	return rtas_read_config(pdn, where, size, val);
	}

	/**
	* pseries_eeh_write_config - Write PCI config space
	* @dn: 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 device_node *dn, int where, int size, u32 val)
	{
	struct pci_dn *pdn;

	pdn = PCI_DN(dn);

	return rtas_write_config(pdn, where, size, val);
	}

	static struct eeh_ops pseries_eeh_ops = {
	.name = "pseries",
	.init = pseries_eeh_init,
	.of_probe = pseries_eeh_of_probe,
	.dev_probe = NULL,
	.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,
	.read_config = pseries_eeh_read_config,
	.write_config = pseries_eeh_write_config
	};

	/**
	* 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 = -EINVAL;

	if (!machine_is(pseries))
	return 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;
	}

	early_initcall(eeh_pseries_init);