linux/include/linux/edac.h

/*
 * Generic EDAC defs
 *
 * Author: Dave Jiang <djiang@mvista.com>
 *
 * 2006-2008 (c) MontaVista Software, Inc. This file is licensed under
 * the terms of the GNU General Public License version 2. This program
 * is licensed "as is" without any warranty of any kind, whether express
 * or implied.
 *
 */
#ifndef _LINUX_EDAC_H_
#define _LINUX_EDAC_H_

#include <linux/atomic.h>
#include <linux/device.h>

#define EDAC_OPSTATE_INVAL	-1
#define EDAC_OPSTATE_POLL	0
#define EDAC_OPSTATE_NMI	1
#define EDAC_OPSTATE_INT	2

extern int edac_op_state;
extern int edac_err_assert;
extern atomic_t edac_handlers;
extern struct bus_type edac_subsys;

extern int edac_handler_set(void);
extern void edac_atomic_assert_error(void);
extern struct bus_type *edac_get_sysfs_subsys(void);
extern void edac_put_sysfs_subsys(void);

static inline void opstate_init(void)
{
	switch (edac_op_state) {
	case EDAC_OPSTATE_POLL:
	case EDAC_OPSTATE_NMI:
		break;
	default:
		edac_op_state = EDAC_OPSTATE_POLL;
	}
	return;
}

#define EDAC_MC_LABEL_LEN	31
#define MC_PROC_NAME_MAX_LEN	7

/* memory devices */
enum dev_type {
	DEV_UNKNOWN = 0,
	DEV_X1,
	DEV_X2,
	DEV_X4,
	DEV_X8,
	DEV_X16,
	DEV_X32,		/* Do these parts exist? */
	DEV_X64			/* Do these parts exist? */
};

#define DEV_FLAG_UNKNOWN	BIT(DEV_UNKNOWN)
#define DEV_FLAG_X1		BIT(DEV_X1)
#define DEV_FLAG_X2		BIT(DEV_X2)
#define DEV_FLAG_X4		BIT(DEV_X4)
#define DEV_FLAG_X8		BIT(DEV_X8)
#define DEV_FLAG_X16		BIT(DEV_X16)
#define DEV_FLAG_X32		BIT(DEV_X32)
#define DEV_FLAG_X64		BIT(DEV_X64)

/* memory types */
enum mem_type {
	MEM_EMPTY = 0,		/* Empty csrow */
	MEM_RESERVED,		/* Reserved csrow type */
	MEM_UNKNOWN,		/* Unknown csrow type */
	MEM_FPM,		/* Fast page mode */
	MEM_EDO,		/* Extended data out */
	MEM_BEDO,		/* Burst Extended data out */
	MEM_SDR,		/* Single data rate SDRAM */
	MEM_RDR,		/* Registered single data rate SDRAM */
	MEM_DDR,		/* Double data rate SDRAM */
	MEM_RDDR,		/* Registered Double data rate SDRAM */
	MEM_RMBS,		/* Rambus DRAM */
	MEM_DDR2,		/* DDR2 RAM */
	MEM_FB_DDR2,		/* fully buffered DDR2 */
	MEM_RDDR2,		/* Registered DDR2 RAM */
	MEM_XDR,		/* Rambus XDR */
	MEM_DDR3,		/* DDR3 RAM */
	MEM_RDDR3,		/* Registered DDR3 RAM */
};

#define MEM_FLAG_EMPTY		BIT(MEM_EMPTY)
#define MEM_FLAG_RESERVED	BIT(MEM_RESERVED)
#define MEM_FLAG_UNKNOWN	BIT(MEM_UNKNOWN)
#define MEM_FLAG_FPM		BIT(MEM_FPM)
#define MEM_FLAG_EDO		BIT(MEM_EDO)
#define MEM_FLAG_BEDO		BIT(MEM_BEDO)
#define MEM_FLAG_SDR		BIT(MEM_SDR)
#define MEM_FLAG_RDR		BIT(MEM_RDR)
#define MEM_FLAG_DDR		BIT(MEM_DDR)
#define MEM_FLAG_RDDR		BIT(MEM_RDDR)
#define MEM_FLAG_RMBS		BIT(MEM_RMBS)
#define MEM_FLAG_DDR2           BIT(MEM_DDR2)
#define MEM_FLAG_FB_DDR2        BIT(MEM_FB_DDR2)
#define MEM_FLAG_RDDR2          BIT(MEM_RDDR2)
#define MEM_FLAG_XDR            BIT(MEM_XDR)
#define MEM_FLAG_DDR3		 BIT(MEM_DDR3)
#define MEM_FLAG_RDDR3		 BIT(MEM_RDDR3)

/* chipset Error Detection and Correction capabilities and mode */
enum edac_type {
	EDAC_UNKNOWN = 0,	/* Unknown if ECC is available */
	EDAC_NONE,		/* Doesn't support ECC */
	EDAC_RESERVED,		/* Reserved ECC type */
	EDAC_PARITY,		/* Detects parity errors */
	EDAC_EC,		/* Error Checking - no correction */
	EDAC_SECDED,		/* Single bit error correction, Double detection */
	EDAC_S2ECD2ED,		/* Chipkill x2 devices - do these exist? */
	EDAC_S4ECD4ED,		/* Chipkill x4 devices */
	EDAC_S8ECD8ED,		/* Chipkill x8 devices */
	EDAC_S16ECD16ED,	/* Chipkill x16 devices */
};

#define EDAC_FLAG_UNKNOWN	BIT(EDAC_UNKNOWN)
#define EDAC_FLAG_NONE		BIT(EDAC_NONE)
#define EDAC_FLAG_PARITY	BIT(EDAC_PARITY)
#define EDAC_FLAG_EC		BIT(EDAC_EC)
#define EDAC_FLAG_SECDED	BIT(EDAC_SECDED)
#define EDAC_FLAG_S2ECD2ED	BIT(EDAC_S2ECD2ED)
#define EDAC_FLAG_S4ECD4ED	BIT(EDAC_S4ECD4ED)
#define EDAC_FLAG_S8ECD8ED	BIT(EDAC_S8ECD8ED)
#define EDAC_FLAG_S16ECD16ED	BIT(EDAC_S16ECD16ED)

/* scrubbing capabilities */
enum scrub_type {
	SCRUB_UNKNOWN = 0,	/* Unknown if scrubber is available */
	SCRUB_NONE,		/* No scrubber */
	SCRUB_SW_PROG,		/* SW progressive (sequential) scrubbing */
	SCRUB_SW_SRC,		/* Software scrub only errors */
	SCRUB_SW_PROG_SRC,	/* Progressive software scrub from an error */
	SCRUB_SW_TUNABLE,	/* Software scrub frequency is tunable */
	SCRUB_HW_PROG,		/* HW progressive (sequential) scrubbing */
	SCRUB_HW_SRC,		/* Hardware scrub only errors */
	SCRUB_HW_PROG_SRC,	/* Progressive hardware scrub from an error */
	SCRUB_HW_TUNABLE	/* Hardware scrub frequency is tunable */
};

#define SCRUB_FLAG_SW_PROG	BIT(SCRUB_SW_PROG)
#define SCRUB_FLAG_SW_SRC	BIT(SCRUB_SW_SRC)
#define SCRUB_FLAG_SW_PROG_SRC	BIT(SCRUB_SW_PROG_SRC)
#define SCRUB_FLAG_SW_TUN	BIT(SCRUB_SW_SCRUB_TUNABLE)
#define SCRUB_FLAG_HW_PROG	BIT(SCRUB_HW_PROG)
#define SCRUB_FLAG_HW_SRC	BIT(SCRUB_HW_SRC)
#define SCRUB_FLAG_HW_PROG_SRC	BIT(SCRUB_HW_PROG_SRC)
#define SCRUB_FLAG_HW_TUN	BIT(SCRUB_HW_TUNABLE)

/* FIXME - should have notify capabilities: NMI, LOG, PROC, etc */

/* EDAC internal operation states */
#define	OP_ALLOC		0x100
#define OP_RUNNING_POLL		0x201
#define OP_RUNNING_INTERRUPT	0x202
#define OP_RUNNING_POLL_INTR	0x203
#define OP_OFFLINE		0x300

/*
 * There are several things to be aware of that aren't at all obvious:
 *
 *
 * SOCKETS, SOCKET SETS, BANKS, ROWS, CHIP-SELECT ROWS, CHANNELS, etc..
 *
 * These are some of the many terms that are thrown about that don't always
 * mean what people think they mean (Inconceivable!).  In the interest of
 * creating a common ground for discussion, terms and their definitions
 * will be established.
 *
 * Memory devices:	The individual chip on a memory stick.  These devices
 *			commonly output 4 and 8 bits each.  Grouping several
 *			of these in parallel provides 64 bits which is common
 *			for a memory stick.
 *
 * Memory Stick:	A printed circuit board that aggregates multiple
 *			memory devices in parallel.  This is the atomic
 *			memory component that is purchaseable by Joe consumer
 *			and loaded into a memory socket.
 *
 * Socket:		A physical connector on the motherboard that accepts
 *			a single memory stick.
 *
 * Channel:		Set of memory devices on a memory stick that must be
 *			grouped in parallel with one or more additional
 *			channels from other memory sticks.  This parallel
 *			grouping of the output from multiple channels are
 *			necessary for the smallest granularity of memory access.
 *			Some memory controllers are capable of single channel -
 *			which means that memory sticks can be loaded
 *			individually.  Other memory controllers are only
 *			capable of dual channel - which means that memory
 *			sticks must be loaded as pairs (see "socket set").
 *
 * Chip-select row:	All of the memory devices that are selected together.
 *			for a single, minimum grain of memory access.
 *			This selects all of the parallel memory devices across
 *			all of the parallel channels.  Common chip-select rows
 *			for single channel are 64 bits, for dual channel 128
 *			bits.
 *
 * Single-Ranked stick:	A Single-ranked stick has 1 chip-select row of memory.
 *			Motherboards commonly drive two chip-select pins to
 *			a memory stick. A single-ranked stick, will occupy
 *			only one of those rows. The other will be unused.
 *
 * Double-Ranked stick:	A double-ranked stick has two chip-select rows which
 *			access different sets of memory devices.  The two
 *			rows cannot be accessed concurrently.
 *
 * Double-sided stick:	DEPRECATED TERM, see Double-Ranked stick.
 *			A double-sided stick has two chip-select rows which
 *			access different sets of memory devices.  The two
 *			rows cannot be accessed concurrently.  "Double-sided"
 *			is irrespective of the memory devices being mounted
 *			on both sides of the memory stick.
 *
 * Socket set:		All of the memory sticks that are required for
 *			a single memory access or all of the memory sticks
 *			spanned by a chip-select row.  A single socket set
 *			has two chip-select rows and if double-sided sticks
 *			are used these will occupy those chip-select rows.
 *
 * Bank:		This term is avoided because it is unclear when
 *			needing to distinguish between chip-select rows and
 *			socket sets.
 *
 * Controller pages:
 *
 * Physical pages:
 *
 * Virtual pages:
 *
 *
 * STRUCTURE ORGANIZATION AND CHOICES
 *
 *
 *
 * PS - I enjoyed writing all that about as much as you enjoyed reading it.
 */

struct channel_info {
	int chan_idx;		/* channel index */
	u32 ce_count;		/* Correctable Errors for this CHANNEL */
	char label[EDAC_MC_LABEL_LEN + 1];	/* DIMM label on motherboard */
	struct csrow_info *csrow;	/* the parent */
};

struct csrow_info {
	unsigned long first_page;	/* first page number in dimm */
	unsigned long last_page;	/* last page number in dimm */
	unsigned long page_mask;	/* used for interleaving -
					 * 0UL for non intlv
					 */
	u32 nr_pages;		/* number of pages in csrow */
	u32 grain;		/* granularity of reported error in bytes */
	int csrow_idx;		/* the chip-select row */
	enum dev_type dtype;	/* memory device type */
	u32 ue_count;		/* Uncorrectable Errors for this csrow */
	u32 ce_count;		/* Correctable Errors for this csrow */
	enum mem_type mtype;	/* memory csrow type */
	enum edac_type edac_mode;	/* EDAC mode for this csrow */
	struct mem_ctl_info *mci;	/* the parent */

	struct kobject kobj;	/* sysfs kobject for this csrow */

	/* channel information for this csrow */
	u32 nr_channels;
	struct channel_info *channels;
};

struct mcidev_sysfs_group {
	const char *name;				/* group name */
	const struct mcidev_sysfs_attribute *mcidev_attr; /* group attributes */
};

struct mcidev_sysfs_group_kobj {
	struct list_head list;		/* list for all instances within a mc */

	struct kobject kobj;		/* kobj for the group */

	const struct mcidev_sysfs_group *grp;	/* group description table */
	struct mem_ctl_info *mci;	/* the parent */
};

/* mcidev_sysfs_attribute structure
 *	used for driver sysfs attributes and in mem_ctl_info
 * 	sysfs top level entries
 */
struct mcidev_sysfs_attribute {
	/* It should use either attr or grp */
	struct attribute attr;
	const struct mcidev_sysfs_group *grp;	/* Points to a group of attributes */

	/* Ops for show/store values at the attribute - not used on group */
        ssize_t (*show)(struct mem_ctl_info *,char *);
        ssize_t (*store)(struct mem_ctl_info *, const char *,size_t);
};

/* MEMORY controller information structure
 */
struct mem_ctl_info {
	struct list_head link;	/* for global list of mem_ctl_info structs */

	struct module *owner;	/* Module owner of this control struct */

	unsigned long mtype_cap;	/* memory types supported by mc */
	unsigned long edac_ctl_cap;	/* Mem controller EDAC capabilities */
	unsigned long edac_cap;	/* configuration capabilities - this is
				 * closely related to edac_ctl_cap.  The
				 * difference is that the controller may be
				 * capable of s4ecd4ed which would be listed
				 * in edac_ctl_cap, but if channels aren't
				 * capable of s4ecd4ed then the edac_cap would
				 * not have that capability.
				 */
	unsigned long scrub_cap;	/* chipset scrub capabilities */
	enum scrub_type scrub_mode;	/* current scrub mode */

	/* Translates sdram memory scrub rate given in bytes/sec to the
	   internal representation and configures whatever else needs
	   to be configured.
	 */
	int (*set_sdram_scrub_rate) (struct mem_ctl_info * mci, u32 bw);

	/* Get the current sdram memory scrub rate from the internal
	   representation and converts it to the closest matching
	   bandwidth in bytes/sec.
	 */
	int (*get_sdram_scrub_rate) (struct mem_ctl_info * mci);


	/* pointer to edac checking routine */
	void (*edac_check) (struct mem_ctl_info * mci);

	/*
	 * Remaps memory pages: controller pages to physical pages.
	 * For most MC's, this will be NULL.
	 */
	/* FIXME - why not send the phys page to begin with? */
	unsigned long (*ctl_page_to_phys) (struct mem_ctl_info * mci,
					   unsigned long page);
	int mc_idx;
	int nr_csrows;
	struct csrow_info *csrows;
	/*
	 * FIXME - what about controllers on other busses? - IDs must be
	 * unique.  dev pointer should be sufficiently unique, but
	 * BUS:SLOT.FUNC numbers may not be unique.
	 */
	struct device *dev;
	const char *mod_name;
	const char *mod_ver;
	const char *ctl_name;
	const char *dev_name;
	char proc_name[MC_PROC_NAME_MAX_LEN + 1];
	void *pvt_info;
	u32 ue_noinfo_count;	/* Uncorrectable Errors w/o info */
	u32 ce_noinfo_count;	/* Correctable Errors w/o info */
	u32 ue_count;		/* Total Uncorrectable Errors for this MC */
	u32 ce_count;		/* Total Correctable Errors for this MC */
	unsigned long start_time;	/* mci load start time (in jiffies) */

	struct completion complete;

	/* edac sysfs device control */
	struct kobject edac_mci_kobj;

	/* list for all grp instances within a mc */
	struct list_head grp_kobj_list;

	/* Additional top controller level attributes, but specified
	 * by the low level driver.
	 *
	 * Set by the low level driver to provide attributes at the
	 * controller level, same level as 'ue_count' and 'ce_count' above.
	 * An array of structures, NULL terminated
	 *
	 * If attributes are desired, then set to array of attributes
	 * If no attributes are desired, leave NULL
	 */
	const struct mcidev_sysfs_attribute *mc_driver_sysfs_attributes;

	/* work struct for this MC */
	struct delayed_work work;

	/* the internal state of this controller instance */
	int op_state;
};

#endif