/*
   * Intel 5100 Memory Controllers kernel module
   *
   * This file may be distributed under the terms of the
   * GNU General Public License.
   *
   * This module is based on the following document:
   *
   * Intel 5100X Chipset Memory Controller Hub (MCH) - Datasheet
   *      http://download.intel.com/design/chipsets/datashts/318378.pdf
   *
   * The intel 5100 has two independent channels. EDAC core currently
   * can not reflect this configuration so instead the chip-select
   * rows for each respective channel are laid out one after another,
   * the first half belonging to channel 0, the second half belonging
   * to channel 1.
   *
   * This driver is for DDR2 DIMMs, and it uses chip select to select among the
   * several ranks. However, instead of showing memories as ranks, it outputs
   * them as DIMM's. An internal table creates the association between ranks
   * and DIMM's.
   */
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/pci.h>
  #include <linux/pci_ids.h>
  #include <linux/edac.h>
  #include <linux/delay.h>
  #include <linux/mmzone.h>
  #include <linux/debugfs.h>
  
  #include "edac_core.h"
  
  /* register addresses */
  
  /* device 16, func 1 */
  #define I5100_MC		0x40	/* Memory Control Register */
  #define 	I5100_MC_SCRBEN_MASK	(1 << 7)
  #define 	I5100_MC_SCRBDONE_MASK	(1 << 4)
  #define I5100_MS		0x44	/* Memory Status Register */
  #define I5100_SPDDATA		0x48	/* Serial Presence Detect Status Reg */
  #define I5100_SPDCMD		0x4c	/* Serial Presence Detect Command Reg */
  #define I5100_TOLM		0x6c	/* Top of Low Memory */
  #define I5100_MIR0		0x80	/* Memory Interleave Range 0 */
  #define I5100_MIR1		0x84	/* Memory Interleave Range 1 */
  #define I5100_AMIR_0		0x8c	/* Adjusted Memory Interleave Range 0 */
  #define I5100_AMIR_1		0x90	/* Adjusted Memory Interleave Range 1 */
  #define I5100_FERR_NF_MEM	0xa0	/* MC First Non Fatal Errors */
  #define		I5100_FERR_NF_MEM_M16ERR_MASK	(1 << 16)
  #define		I5100_FERR_NF_MEM_M15ERR_MASK	(1 << 15)
  #define		I5100_FERR_NF_MEM_M14ERR_MASK	(1 << 14)
  #define		I5100_FERR_NF_MEM_M12ERR_MASK	(1 << 12)
  #define		I5100_FERR_NF_MEM_M11ERR_MASK	(1 << 11)
  #define		I5100_FERR_NF_MEM_M10ERR_MASK	(1 << 10)
  #define		I5100_FERR_NF_MEM_M6ERR_MASK	(1 << 6)
  #define		I5100_FERR_NF_MEM_M5ERR_MASK	(1 << 5)
  #define		I5100_FERR_NF_MEM_M4ERR_MASK	(1 << 4)
  #define		I5100_FERR_NF_MEM_M1ERR_MASK	(1 << 1)
  #define		I5100_FERR_NF_MEM_ANY_MASK	\
  			(I5100_FERR_NF_MEM_M16ERR_MASK | \
  			I5100_FERR_NF_MEM_M15ERR_MASK | \
  			I5100_FERR_NF_MEM_M14ERR_MASK | \
  			I5100_FERR_NF_MEM_M12ERR_MASK | \
  			I5100_FERR_NF_MEM_M11ERR_MASK | \
  			I5100_FERR_NF_MEM_M10ERR_MASK | \
  			I5100_FERR_NF_MEM_M6ERR_MASK | \
  			I5100_FERR_NF_MEM_M5ERR_MASK | \
  			I5100_FERR_NF_MEM_M4ERR_MASK | \
  			I5100_FERR_NF_MEM_M1ERR_MASK)
  #define	I5100_NERR_NF_MEM	0xa4	/* MC Next Non-Fatal Errors */
  #define I5100_EMASK_MEM		0xa8	/* MC Error Mask Register */
  #define I5100_MEM0EINJMSK0	0x200	/* Injection Mask0 Register Channel 0 */
  #define I5100_MEM1EINJMSK0	0x208	/* Injection Mask0 Register Channel 1 */
  #define		I5100_MEMXEINJMSK0_EINJEN	(1 << 27)
  #define I5100_MEM0EINJMSK1	0x204	/* Injection Mask1 Register Channel 0 */
  #define I5100_MEM1EINJMSK1	0x206	/* Injection Mask1 Register Channel 1 */
  
  /* Device 19, Function 0 */
  #define I5100_DINJ0 0x9a
  
  /* device 21 and 22, func 0 */
  #define I5100_MTR_0	0x154	/* Memory Technology Registers 0-3 */
  #define I5100_DMIR	0x15c	/* DIMM Interleave Range */
  #define	I5100_VALIDLOG	0x18c	/* Valid Log Markers */
  #define	I5100_NRECMEMA	0x190	/* Non-Recoverable Memory Error Log Reg A */
  #define	I5100_NRECMEMB	0x194	/* Non-Recoverable Memory Error Log Reg B */
  #define	I5100_REDMEMA	0x198	/* Recoverable Memory Data Error Log Reg A */
  #define	I5100_REDMEMB	0x19c	/* Recoverable Memory Data Error Log Reg B */
  #define	I5100_RECMEMA	0x1a0	/* Recoverable Memory Error Log Reg A */
  #define	I5100_RECMEMB	0x1a4	/* Recoverable Memory Error Log Reg B */
  #define I5100_MTR_4	0x1b0	/* Memory Technology Registers 4,5 */
  
  /* bit field accessors */
  
  static inline u32 i5100_mc_scrben(u32 mc)
  {
  	return mc >> 7 & 1;
  }
  
  static inline u32 i5100_mc_errdeten(u32 mc)
  {
  	return mc >> 5 & 1;
  }
  
  static inline u32 i5100_mc_scrbdone(u32 mc)
  {
  	return mc >> 4 & 1;
  }
  
  static inline u16 i5100_spddata_rdo(u16 a)
  {
  	return a >> 15 & 1;
  }
  
  static inline u16 i5100_spddata_sbe(u16 a)
  {
  	return a >> 13 & 1;
  }
  
  static inline u16 i5100_spddata_busy(u16 a)
  {
  	return a >> 12 & 1;
  }
  
  static inline u16 i5100_spddata_data(u16 a)
  {
  	return a & ((1 << 8) - 1);
  }
  
  static inline u32 i5100_spdcmd_create(u32 dti, u32 ckovrd, u32 sa, u32 ba,
  				      u32 data, u32 cmd)
  {
  	return	((dti & ((1 << 4) - 1))  << 28) |
  		((ckovrd & 1)            << 27) |
  		((sa & ((1 << 3) - 1))   << 24) |
  		((ba & ((1 << 8) - 1))   << 16) |
  		((data & ((1 << 8) - 1)) <<  8) |
  		(cmd & 1);
  }
  
  static inline u16 i5100_tolm_tolm(u16 a)
  {
  	return a >> 12 & ((1 << 4) - 1);
  }
  
  static inline u16 i5100_mir_limit(u16 a)
  {
  	return a >> 4 & ((1 << 12) - 1);
  }
  
  static inline u16 i5100_mir_way1(u16 a)
  {
  	return a >> 1 & 1;
  }
  
  static inline u16 i5100_mir_way0(u16 a)
  {
  	return a & 1;
  }
  
  static inline u32 i5100_ferr_nf_mem_chan_indx(u32 a)
  {
  	return a >> 28 & 1;
  }
  
  static inline u32 i5100_ferr_nf_mem_any(u32 a)
  {
  	return a & I5100_FERR_NF_MEM_ANY_MASK;
  }
  
  static inline u32 i5100_nerr_nf_mem_any(u32 a)
  {
  	return i5100_ferr_nf_mem_any(a);
  }
  
  static inline u32 i5100_dmir_limit(u32 a)
  {
  	return a >> 16 & ((1 << 11) - 1);
  }
  
  static inline u32 i5100_dmir_rank(u32 a, u32 i)
  {
  	return a >> (4 * i) & ((1 << 2) - 1);
  }
  
  static inline u16 i5100_mtr_present(u16 a)
  {
  	return a >> 10 & 1;
  }
  
  static inline u16 i5100_mtr_ethrottle(u16 a)
  {
  	return a >> 9 & 1;
  }
  
  static inline u16 i5100_mtr_width(u16 a)
  {
  	return a >> 8 & 1;
  }
  
  static inline u16 i5100_mtr_numbank(u16 a)
  {
  	return a >> 6 & 1;
  }
  
  static inline u16 i5100_mtr_numrow(u16 a)
  {
  	return a >> 2 & ((1 << 2) - 1);
  }
  
  static inline u16 i5100_mtr_numcol(u16 a)
  {
  	return a & ((1 << 2) - 1);
  }
  
  
  static inline u32 i5100_validlog_redmemvalid(u32 a)
  {
  	return a >> 2 & 1;
  }
  
  static inline u32 i5100_validlog_recmemvalid(u32 a)
  {
  	return a >> 1 & 1;
  }
  
  static inline u32 i5100_validlog_nrecmemvalid(u32 a)
  {
  	return a & 1;
  }
  
  static inline u32 i5100_nrecmema_merr(u32 a)
  {
  	return a >> 15 & ((1 << 5) - 1);
  }
  
  static inline u32 i5100_nrecmema_bank(u32 a)
  {
  	return a >> 12 & ((1 << 3) - 1);
  }
  
  static inline u32 i5100_nrecmema_rank(u32 a)
  {
  	return a >>  8 & ((1 << 3) - 1);
  }
  
  static inline u32 i5100_nrecmema_dm_buf_id(u32 a)
  {
  	return a & ((1 << 8) - 1);
  }
  
  static inline u32 i5100_nrecmemb_cas(u32 a)
  {
  	return a >> 16 & ((1 << 13) - 1);
  }
  
  static inline u32 i5100_nrecmemb_ras(u32 a)
  {
  	return a & ((1 << 16) - 1);
  }
  
  static inline u32 i5100_redmemb_ecc_locator(u32 a)
  {
  	return a & ((1 << 18) - 1);
  }
  
  static inline u32 i5100_recmema_merr(u32 a)
  {
  	return i5100_nrecmema_merr(a);
  }
  
  static inline u32 i5100_recmema_bank(u32 a)
  {
  	return i5100_nrecmema_bank(a);
  }
  
  static inline u32 i5100_recmema_rank(u32 a)
  {
  	return i5100_nrecmema_rank(a);
  }
  
  static inline u32 i5100_recmema_dm_buf_id(u32 a)
  {
  	return i5100_nrecmema_dm_buf_id(a);
  }
  
  static inline u32 i5100_recmemb_cas(u32 a)
  {
  	return i5100_nrecmemb_cas(a);
  }
  
  static inline u32 i5100_recmemb_ras(u32 a)
  {
  	return i5100_nrecmemb_ras(a);
  }
  
  /* some generic limits */
  #define I5100_MAX_RANKS_PER_CHAN	6
  #define I5100_CHANNELS			    2
  #define I5100_MAX_RANKS_PER_DIMM	4
  #define I5100_DIMM_ADDR_LINES		(6 - 3)	/* 64 bits / 8 bits per byte */
  #define I5100_MAX_DIMM_SLOTS_PER_CHAN	4
  #define I5100_MAX_RANK_INTERLEAVE	4
  #define I5100_MAX_DMIRS			5
  #define I5100_SCRUB_REFRESH_RATE	(5 * 60 * HZ)
  
  struct i5100_priv {
  	/* ranks on each dimm -- 0 maps to not present -- obtained via SPD */
  	int dimm_numrank[I5100_CHANNELS][I5100_MAX_DIMM_SLOTS_PER_CHAN];
  
  	/*
  	 * mainboard chip select map -- maps i5100 chip selects to
  	 * DIMM slot chip selects.  In the case of only 4 ranks per
  	 * channel, the mapping is fairly obvious but not unique.
  	 * we map -1 -> NC and assume both channels use the same
  	 * map...
  	 *
  	 */
  	int dimm_csmap[I5100_MAX_DIMM_SLOTS_PER_CHAN][I5100_MAX_RANKS_PER_DIMM];
  
  	/* memory interleave range */
  	struct {
  		u64	 limit;
  		unsigned way[2];
  	} mir[I5100_CHANNELS];
  
  	/* adjusted memory interleave range register */
  	unsigned amir[I5100_CHANNELS];
  
  	/* dimm interleave range */
  	struct {
  		unsigned rank[I5100_MAX_RANK_INTERLEAVE];
  		u64	 limit;
  	} dmir[I5100_CHANNELS][I5100_MAX_DMIRS];
  
  	/* memory technology registers... */
  	struct {
  		unsigned present;	/* 0 or 1 */
  		unsigned ethrottle;	/* 0 or 1 */
  		unsigned width;		/* 4 or 8 bits  */
  		unsigned numbank;	/* 2 or 3 lines */
  		unsigned numrow;	/* 13 .. 16 lines */
  		unsigned numcol;	/* 11 .. 12 lines */
  	} mtr[I5100_CHANNELS][I5100_MAX_RANKS_PER_CHAN];
  
  	u64 tolm;		/* top of low memory in bytes */
  	unsigned ranksperchan;	/* number of ranks per channel */
  
  	struct pci_dev *mc;	/* device 16 func 1 */
  	struct pci_dev *einj;	/* device 19 func 0 */
  	struct pci_dev *ch0mm;	/* device 21 func 0 */
  	struct pci_dev *ch1mm;	/* device 22 func 0 */
  
  	struct delayed_work i5100_scrubbing;
  	int scrub_enable;
  
  	/* Error injection */
  	u8 inject_channel;
  	u8 inject_hlinesel;
  	u8 inject_deviceptr1;
  	u8 inject_deviceptr2;
  	u16 inject_eccmask1;
  	u16 inject_eccmask2;
  
  	struct dentry *debugfs;
  };
  
  static struct dentry *i5100_debugfs;
  
  /* map a rank/chan to a slot number on the mainboard */
  static int i5100_rank_to_slot(const struct mem_ctl_info *mci,
  			      int chan, int rank)
  {
  	const struct i5100_priv *priv = mci->pvt_info;
  	int i;
  
  	for (i = 0; i < I5100_MAX_DIMM_SLOTS_PER_CHAN; i++) {
  		int j;
  		const int numrank = priv->dimm_numrank[chan][i];
  
  		for (j = 0; j < numrank; j++)
  			if (priv->dimm_csmap[i][j] == rank)
  				return i * 2 + chan;
  	}
  
  	return -1;
  }
  
  static const char *i5100_err_msg(unsigned err)
  {
  	static const char *merrs[] = {
  		"unknown", /* 0 */
  		"uncorrectable data ECC on replay", /* 1 */
  		"unknown", /* 2 */
  		"unknown", /* 3 */
  		"aliased uncorrectable demand data ECC", /* 4 */
  		"aliased uncorrectable spare-copy data ECC", /* 5 */
  		"aliased uncorrectable patrol data ECC", /* 6 */
  		"unknown", /* 7 */
  		"unknown", /* 8 */
  		"unknown", /* 9 */
  		"non-aliased uncorrectable demand data ECC", /* 10 */
  		"non-aliased uncorrectable spare-copy data ECC", /* 11 */
  		"non-aliased uncorrectable patrol data ECC", /* 12 */
  		"unknown", /* 13 */
  		"correctable demand data ECC", /* 14 */
  		"correctable spare-copy data ECC", /* 15 */
  		"correctable patrol data ECC", /* 16 */
  		"unknown", /* 17 */
  		"SPD protocol error", /* 18 */
  		"unknown", /* 19 */
  		"spare copy initiated", /* 20 */
  		"spare copy completed", /* 21 */
  	};
  	unsigned i;
  
  	for (i = 0; i < ARRAY_SIZE(merrs); i++)
  		if (1 << i & err)
  			return merrs[i];
  
  	return "none";
  }
  
  /* convert csrow index into a rank (per channel -- 0..5) */
  static int i5100_csrow_to_rank(const struct mem_ctl_info *mci, int csrow)
  {
  	const struct i5100_priv *priv = mci->pvt_info;
  
  	return csrow % priv->ranksperchan;
  }
  
  /* convert csrow index into a channel (0..1) */
  static int i5100_csrow_to_chan(const struct mem_ctl_info *mci, int csrow)
  {
  	const struct i5100_priv *priv = mci->pvt_info;
  
  	return csrow / priv->ranksperchan;
  }
  
  static void i5100_handle_ce(struct mem_ctl_info *mci,
  			    int chan,
  			    unsigned bank,
  			    unsigned rank,
  			    unsigned long syndrome,
  			    unsigned cas,
  			    unsigned ras,
  			    const char *msg)
  {
  	char detail[80];
  
  	/* Form out message */
  	snprintf(detail, sizeof(detail),
  		 "bank %u, cas %u, ras %u
  ",
  		 bank, cas, ras);
  
  	edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
  			     0, 0, syndrome,
  			     chan, rank, -1,
  			     msg, detail);
  }
  
  static void i5100_handle_ue(struct mem_ctl_info *mci,
  			    int chan,
  			    unsigned bank,
  			    unsigned rank,
  			    unsigned long syndrome,
  			    unsigned cas,
  			    unsigned ras,
  			    const char *msg)
  {
  	char detail[80];
  
  	/* Form out message */
  	snprintf(detail, sizeof(detail),
  		 "bank %u, cas %u, ras %u
  ",
  		 bank, cas, ras);
  
  	edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
  			     0, 0, syndrome,
  			     chan, rank, -1,
  			     msg, detail);
  }
  
  static void i5100_read_log(struct mem_ctl_info *mci, int chan,
  			   u32 ferr, u32 nerr)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	struct pci_dev *pdev = (chan) ? priv->ch1mm : priv->ch0mm;
  	u32 dw;
  	u32 dw2;
  	unsigned syndrome = 0;
  	unsigned ecc_loc = 0;
  	unsigned merr;
  	unsigned bank;
  	unsigned rank;
  	unsigned cas;
  	unsigned ras;
  
  	pci_read_config_dword(pdev, I5100_VALIDLOG, &dw);
  
  	if (i5100_validlog_redmemvalid(dw)) {
  		pci_read_config_dword(pdev, I5100_REDMEMA, &dw2);
  		syndrome = dw2;
  		pci_read_config_dword(pdev, I5100_REDMEMB, &dw2);
  		ecc_loc = i5100_redmemb_ecc_locator(dw2);
  	}
  
  	if (i5100_validlog_recmemvalid(dw)) {
  		const char *msg;
  
  		pci_read_config_dword(pdev, I5100_RECMEMA, &dw2);
  		merr = i5100_recmema_merr(dw2);
  		bank = i5100_recmema_bank(dw2);
  		rank = i5100_recmema_rank(dw2);
  
  		pci_read_config_dword(pdev, I5100_RECMEMB, &dw2);
  		cas = i5100_recmemb_cas(dw2);
  		ras = i5100_recmemb_ras(dw2);
  
  		/* FIXME:  not really sure if this is what merr is...
  		 */
  		if (!merr)
  			msg = i5100_err_msg(ferr);
  		else
  			msg = i5100_err_msg(nerr);
  
  		i5100_handle_ce(mci, chan, bank, rank, syndrome, cas, ras, msg);
  	}
  
  	if (i5100_validlog_nrecmemvalid(dw)) {
  		const char *msg;
  
  		pci_read_config_dword(pdev, I5100_NRECMEMA, &dw2);
  		merr = i5100_nrecmema_merr(dw2);
  		bank = i5100_nrecmema_bank(dw2);
  		rank = i5100_nrecmema_rank(dw2);
  
  		pci_read_config_dword(pdev, I5100_NRECMEMB, &dw2);
  		cas = i5100_nrecmemb_cas(dw2);
  		ras = i5100_nrecmemb_ras(dw2);
  
  		/* FIXME:  not really sure if this is what merr is...
  		 */
  		if (!merr)
  			msg = i5100_err_msg(ferr);
  		else
  			msg = i5100_err_msg(nerr);
  
  		i5100_handle_ue(mci, chan, bank, rank, syndrome, cas, ras, msg);
  	}
  
  	pci_write_config_dword(pdev, I5100_VALIDLOG, dw);
  }
  
  static void i5100_check_error(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	u32 dw, dw2;
  
  	pci_read_config_dword(priv->mc, I5100_FERR_NF_MEM, &dw);
  	if (i5100_ferr_nf_mem_any(dw)) {
  
  		pci_read_config_dword(priv->mc, I5100_NERR_NF_MEM, &dw2);
  
  		i5100_read_log(mci, i5100_ferr_nf_mem_chan_indx(dw),
  			       i5100_ferr_nf_mem_any(dw),
  			       i5100_nerr_nf_mem_any(dw2));
  
  		pci_write_config_dword(priv->mc, I5100_NERR_NF_MEM, dw2);
  	}
  	pci_write_config_dword(priv->mc, I5100_FERR_NF_MEM, dw);
  }
  
  /* The i5100 chipset will scrub the entire memory once, then
   * set a done bit. Continuous scrubbing is achieved by enqueing
   * delayed work to a workqueue, checking every few minutes if
   * the scrubbing has completed and if so reinitiating it.
   */
  
  static void i5100_refresh_scrubbing(struct work_struct *work)
  {
  	struct delayed_work *i5100_scrubbing = container_of(work,
  							    struct delayed_work,
  							    work);
  	struct i5100_priv *priv = container_of(i5100_scrubbing,
  					       struct i5100_priv,
  					       i5100_scrubbing);
  	u32 dw;
  
  	pci_read_config_dword(priv->mc, I5100_MC, &dw);
  
  	if (priv->scrub_enable) {
  
  		pci_read_config_dword(priv->mc, I5100_MC, &dw);
  
  		if (i5100_mc_scrbdone(dw)) {
  			dw |= I5100_MC_SCRBEN_MASK;
  			pci_write_config_dword(priv->mc, I5100_MC, dw);
  			pci_read_config_dword(priv->mc, I5100_MC, &dw);
  		}
  
  		schedule_delayed_work(&(priv->i5100_scrubbing),
  				      I5100_SCRUB_REFRESH_RATE);
  	}
  }
  /*
   * The bandwidth is based on experimentation, feel free to refine it.
   */
  static int i5100_set_scrub_rate(struct mem_ctl_info *mci, u32 bandwidth)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	u32 dw;
  
  	pci_read_config_dword(priv->mc, I5100_MC, &dw);
  	if (bandwidth) {
  		priv->scrub_enable = 1;
  		dw |= I5100_MC_SCRBEN_MASK;
  		schedule_delayed_work(&(priv->i5100_scrubbing),
  				      I5100_SCRUB_REFRESH_RATE);
  	} else {
  		priv->scrub_enable = 0;
  		dw &= ~I5100_MC_SCRBEN_MASK;
  		cancel_delayed_work(&(priv->i5100_scrubbing));
  	}
  	pci_write_config_dword(priv->mc, I5100_MC, dw);
  
  	pci_read_config_dword(priv->mc, I5100_MC, &dw);
  
  	bandwidth = 5900000 * i5100_mc_scrben(dw);
  
  	return bandwidth;
  }
  
  static int i5100_get_scrub_rate(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	u32 dw;
  
  	pci_read_config_dword(priv->mc, I5100_MC, &dw);
  
  	return 5900000 * i5100_mc_scrben(dw);
  }
  
  static struct pci_dev *pci_get_device_func(unsigned vendor,
  					   unsigned device,
  					   unsigned func)
  {
  	struct pci_dev *ret = NULL;
  
  	while (1) {
  		ret = pci_get_device(vendor, device, ret);
  
  		if (!ret)
  			break;
  
  		if (PCI_FUNC(ret->devfn) == func)
  			break;
  	}
  
  	return ret;
  }
  
  static unsigned long i5100_npages(struct mem_ctl_info *mci, int csrow)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	const unsigned chan_rank = i5100_csrow_to_rank(mci, csrow);
  	const unsigned chan = i5100_csrow_to_chan(mci, csrow);
  	unsigned addr_lines;
  
  	/* dimm present? */
  	if (!priv->mtr[chan][chan_rank].present)
  		return 0ULL;
  
  	addr_lines =
  		I5100_DIMM_ADDR_LINES +
  		priv->mtr[chan][chan_rank].numcol +
  		priv->mtr[chan][chan_rank].numrow +
  		priv->mtr[chan][chan_rank].numbank;
  
  	return (unsigned long)
  		((unsigned long long) (1ULL << addr_lines) / PAGE_SIZE);
  }
  
  static void i5100_init_mtr(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	struct pci_dev *mms[2] = { priv->ch0mm, priv->ch1mm };
  	int i;
  
  	for (i = 0; i < I5100_CHANNELS; i++) {
  		int j;
  		struct pci_dev *pdev = mms[i];
  
  		for (j = 0; j < I5100_MAX_RANKS_PER_CHAN; j++) {
  			const unsigned addr =
  				(j < 4) ? I5100_MTR_0 + j * 2 :
  					  I5100_MTR_4 + (j - 4) * 2;
  			u16 w;
  
  			pci_read_config_word(pdev, addr, &w);
  
  			priv->mtr[i][j].present = i5100_mtr_present(w);
  			priv->mtr[i][j].ethrottle = i5100_mtr_ethrottle(w);
  			priv->mtr[i][j].width = 4 + 4 * i5100_mtr_width(w);
  			priv->mtr[i][j].numbank = 2 + i5100_mtr_numbank(w);
  			priv->mtr[i][j].numrow = 13 + i5100_mtr_numrow(w);
  			priv->mtr[i][j].numcol = 10 + i5100_mtr_numcol(w);
  		}
  	}
  }
  
  /*
   * FIXME: make this into a real i2c adapter (so that dimm-decode
   * will work)?
   */
  static int i5100_read_spd_byte(const struct mem_ctl_info *mci,
  			       u8 ch, u8 slot, u8 addr, u8 *byte)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	u16 w;
  	unsigned long et;
  
  	pci_read_config_word(priv->mc, I5100_SPDDATA, &w);
  	if (i5100_spddata_busy(w))
  		return -1;
  
  	pci_write_config_dword(priv->mc, I5100_SPDCMD,
  			       i5100_spdcmd_create(0xa, 1, ch * 4 + slot, addr,
  						   0, 0));
  
  	/* wait up to 100ms */
  	et = jiffies + HZ / 10;
  	udelay(100);
  	while (1) {
  		pci_read_config_word(priv->mc, I5100_SPDDATA, &w);
  		if (!i5100_spddata_busy(w))
  			break;
  		udelay(100);
  	}
  
  	if (!i5100_spddata_rdo(w) || i5100_spddata_sbe(w))
  		return -1;
  
  	*byte = i5100_spddata_data(w);
  
  	return 0;
  }
  
  /*
   * fill dimm chip select map
   *
   * FIXME:
   *   o not the only way to may chip selects to dimm slots
   *   o investigate if there is some way to obtain this map from the bios
   */
  static void i5100_init_dimm_csmap(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	int i;
  
  	for (i = 0; i < I5100_MAX_DIMM_SLOTS_PER_CHAN; i++) {
  		int j;
  
  		for (j = 0; j < I5100_MAX_RANKS_PER_DIMM; j++)
  			priv->dimm_csmap[i][j] = -1; /* default NC */
  	}
  
  	/* only 2 chip selects per slot... */
  	if (priv->ranksperchan == 4) {
  		priv->dimm_csmap[0][0] = 0;
  		priv->dimm_csmap[0][1] = 3;
  		priv->dimm_csmap[1][0] = 1;
  		priv->dimm_csmap[1][1] = 2;
  		priv->dimm_csmap[2][0] = 2;
  		priv->dimm_csmap[3][0] = 3;
  	} else {
  		priv->dimm_csmap[0][0] = 0;
  		priv->dimm_csmap[0][1] = 1;
  		priv->dimm_csmap[1][0] = 2;
  		priv->dimm_csmap[1][1] = 3;
  		priv->dimm_csmap[2][0] = 4;
  		priv->dimm_csmap[2][1] = 5;
  	}
  }
  
  static void i5100_init_dimm_layout(struct pci_dev *pdev,
  				   struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	int i;
  
  	for (i = 0; i < I5100_CHANNELS; i++) {
  		int j;
  
  		for (j = 0; j < I5100_MAX_DIMM_SLOTS_PER_CHAN; j++) {
  			u8 rank;
  
  			if (i5100_read_spd_byte(mci, i, j, 5, &rank) < 0)
  				priv->dimm_numrank[i][j] = 0;
  			else
  				priv->dimm_numrank[i][j] = (rank & 3) + 1;
  		}
  	}
  
  	i5100_init_dimm_csmap(mci);
  }
  
  static void i5100_init_interleaving(struct pci_dev *pdev,
  				    struct mem_ctl_info *mci)
  {
  	u16 w;
  	u32 dw;
  	struct i5100_priv *priv = mci->pvt_info;
  	struct pci_dev *mms[2] = { priv->ch0mm, priv->ch1mm };
  	int i;
  
  	pci_read_config_word(pdev, I5100_TOLM, &w);
  	priv->tolm = (u64) i5100_tolm_tolm(w) * 256 * 1024 * 1024;
  
  	pci_read_config_word(pdev, I5100_MIR0, &w);
  	priv->mir[0].limit = (u64) i5100_mir_limit(w) << 28;
  	priv->mir[0].way[1] = i5100_mir_way1(w);
  	priv->mir[0].way[0] = i5100_mir_way0(w);
  
  	pci_read_config_word(pdev, I5100_MIR1, &w);
  	priv->mir[1].limit = (u64) i5100_mir_limit(w) << 28;
  	priv->mir[1].way[1] = i5100_mir_way1(w);
  	priv->mir[1].way[0] = i5100_mir_way0(w);
  
  	pci_read_config_word(pdev, I5100_AMIR_0, &w);
  	priv->amir[0] = w;
  	pci_read_config_word(pdev, I5100_AMIR_1, &w);
  	priv->amir[1] = w;
  
  	for (i = 0; i < I5100_CHANNELS; i++) {
  		int j;
  
  		for (j = 0; j < 5; j++) {
  			int k;
  
  			pci_read_config_dword(mms[i], I5100_DMIR + j * 4, &dw);
  
  			priv->dmir[i][j].limit =
  				(u64) i5100_dmir_limit(dw) << 28;
  			for (k = 0; k < I5100_MAX_RANKS_PER_DIMM; k++)
  				priv->dmir[i][j].rank[k] =
  					i5100_dmir_rank(dw, k);
  		}
  	}
  
  	i5100_init_mtr(mci);
  }
  
  static void i5100_init_csrows(struct mem_ctl_info *mci)
  {
  	int i;
  	struct i5100_priv *priv = mci->pvt_info;
  
  	for (i = 0; i < mci->tot_dimms; i++) {
  		struct dimm_info *dimm;
  		const unsigned long npages = i5100_npages(mci, i);
  		const unsigned chan = i5100_csrow_to_chan(mci, i);
  		const unsigned rank = i5100_csrow_to_rank(mci, i);
  
  		if (!npages)
  			continue;
  
  		dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms, mci->n_layers,
  			       chan, rank, 0);
  
  		dimm->nr_pages = npages;
  		if (npages) {
  			dimm->grain = 32;
  			dimm->dtype = (priv->mtr[chan][rank].width == 4) ?
  					DEV_X4 : DEV_X8;
  			dimm->mtype = MEM_RDDR2;
  			dimm->edac_mode = EDAC_SECDED;
  			snprintf(dimm->label, sizeof(dimm->label),
  				"DIMM%u",
  				i5100_rank_to_slot(mci, chan, rank));
  		}
  
  		edac_dbg(2, "dimm channel %d, rank %d, size %ld
  ",
  			 chan, rank, (long)PAGES_TO_MiB(npages));
  	}
  }
  
  /****************************************************************************
   *                       Error injection routines
   ****************************************************************************/
  
  static void i5100_do_inject(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  	u32 mask0;
  	u16 mask1;
  
  	/* MEM[1:0]EINJMSK0
  	 * 31    - ADDRMATCHEN
  	 * 29:28 - HLINESEL
  	 *         00 Reserved
  	 *         01 Lower half of cache line
  	 *         10 Upper half of cache line
  	 *         11 Both upper and lower parts of cache line
  	 * 27    - EINJEN
  	 * 25:19 - XORMASK1 for deviceptr1
  	 * 9:5   - SEC2RAM for deviceptr2
  	 * 4:0   - FIR2RAM for deviceptr1
  	 */
  	mask0 = ((priv->inject_hlinesel & 0x3) << 28) |
  		I5100_MEMXEINJMSK0_EINJEN |
  		((priv->inject_eccmask1 & 0xffff) << 10) |
  		((priv->inject_deviceptr2 & 0x1f) << 5) |
  		(priv->inject_deviceptr1 & 0x1f);
  
  	/* MEM[1:0]EINJMSK1
  	 * 15:0  - XORMASK2 for deviceptr2
  	 */
  	mask1 = priv->inject_eccmask2;
  
  	if (priv->inject_channel == 0) {
  		pci_write_config_dword(priv->mc, I5100_MEM0EINJMSK0, mask0);
  		pci_write_config_word(priv->mc, I5100_MEM0EINJMSK1, mask1);
  	} else {
  		pci_write_config_dword(priv->mc, I5100_MEM1EINJMSK0, mask0);
  		pci_write_config_word(priv->mc, I5100_MEM1EINJMSK1, mask1);
  	}
  
  	/* Error Injection Response Function
  	 * Intel 5100 Memory Controller Hub Chipset (318378) datasheet
  	 * hints about this register but carry no data about them. All
  	 * data regarding device 19 is based on experimentation and the
  	 * Intel 7300 Chipset Memory Controller Hub (318082) datasheet
  	 * which appears to be accurate for the i5100 in this area.
  	 *
  	 * The injection code don't work without setting this register.
  	 * The register needs to be flipped off then on else the hardware
  	 * will only preform the first injection.
  	 *
  	 * Stop condition bits 7:4
  	 * 1010 - Stop after one injection
  	 * 1011 - Never stop injecting faults
  	 *
  	 * Start condition bits 3:0
  	 * 1010 - Never start
  	 * 1011 - Start immediately
  	 */
  	pci_write_config_byte(priv->einj, I5100_DINJ0, 0xaa);
  	pci_write_config_byte(priv->einj, I5100_DINJ0, 0xab);
  }
  
  #define to_mci(k) container_of(k, struct mem_ctl_info, dev)
  static ssize_t inject_enable_write(struct file *file, const char __user *data,
  		size_t count, loff_t *ppos)
  {
  	struct device *dev = file->private_data;
  	struct mem_ctl_info *mci = to_mci(dev);
  
  	i5100_do_inject(mci);
  
  	return count;
  }
  
  static const struct file_operations i5100_inject_enable_fops = {
  	.open = simple_open,
  	.write = inject_enable_write,
  	.llseek = generic_file_llseek,
  };
  
  static int i5100_setup_debugfs(struct mem_ctl_info *mci)
  {
  	struct i5100_priv *priv = mci->pvt_info;
  
  	if (!i5100_debugfs)
  		return -ENODEV;
  
  	priv->debugfs = debugfs_create_dir(mci->bus->name, i5100_debugfs);
  
  	if (!priv->debugfs)
  		return -ENOMEM;
  
  	debugfs_create_x8("inject_channel", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_channel);
  	debugfs_create_x8("inject_hlinesel", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_hlinesel);
  	debugfs_create_x8("inject_deviceptr1", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_deviceptr1);
  	debugfs_create_x8("inject_deviceptr2", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_deviceptr2);
  	debugfs_create_x16("inject_eccmask1", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_eccmask1);
  	debugfs_create_x16("inject_eccmask2", S_IRUGO | S_IWUSR, priv->debugfs,
  			&priv->inject_eccmask2);
  	debugfs_create_file("inject_enable", S_IWUSR, priv->debugfs,
  			&mci->dev, &i5100_inject_enable_fops);
  
  	return 0;
  
  }
  
  static int i5100_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
  {
  	int rc;
  	struct mem_ctl_info *mci;
  	struct edac_mc_layer layers[2];
  	struct i5100_priv *priv;
  	struct pci_dev *ch0mm, *ch1mm, *einj;
  	int ret = 0;
  	u32 dw;
  	int ranksperch;
  
  	if (PCI_FUNC(pdev->devfn) != 1)
  		return -ENODEV;
  
  	rc = pci_enable_device(pdev);
  	if (rc < 0) {
  		ret = rc;
  		goto bail;
  	}
  
  	/* ECC enabled? */
  	pci_read_config_dword(pdev, I5100_MC, &dw);
  	if (!i5100_mc_errdeten(dw)) {
  		printk(KERN_INFO "i5100_edac: ECC not enabled.
  ");
  		ret = -ENODEV;
  		goto bail_pdev;
  	}
  
  	/* figure out how many ranks, from strapped state of 48GB_Mode input */
  	pci_read_config_dword(pdev, I5100_MS, &dw);
  	ranksperch = !!(dw & (1 << 8)) * 2 + 4;
  
  	/* enable error reporting... */
  	pci_read_config_dword(pdev, I5100_EMASK_MEM, &dw);
  	dw &= ~I5100_FERR_NF_MEM_ANY_MASK;
  	pci_write_config_dword(pdev, I5100_EMASK_MEM, dw);
  
  	/* device 21, func 0, Channel 0 Memory Map, Error Flag/Mask, etc... */
  	ch0mm = pci_get_device_func(PCI_VENDOR_ID_INTEL,
  				    PCI_DEVICE_ID_INTEL_5100_21, 0);
  	if (!ch0mm) {
  		ret = -ENODEV;
  		goto bail_pdev;
  	}
  
  	rc = pci_enable_device(ch0mm);
  	if (rc < 0) {
  		ret = rc;
  		goto bail_ch0;
  	}
  
  	/* device 22, func 0, Channel 1 Memory Map, Error Flag/Mask, etc... */
  	ch1mm = pci_get_device_func(PCI_VENDOR_ID_INTEL,
  				    PCI_DEVICE_ID_INTEL_5100_22, 0);
  	if (!ch1mm) {
  		ret = -ENODEV;
  		goto bail_disable_ch0;
  	}
  
  	rc = pci_enable_device(ch1mm);
  	if (rc < 0) {
  		ret = rc;
  		goto bail_ch1;
  	}
  
  	layers[0].type = EDAC_MC_LAYER_CHANNEL;
  	layers[0].size = 2;
  	layers[0].is_virt_csrow = false;
  	layers[1].type = EDAC_MC_LAYER_SLOT;
  	layers[1].size = ranksperch;
  	layers[1].is_virt_csrow = true;
  	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
  			    sizeof(*priv));
  	if (!mci) {
  		ret = -ENOMEM;
  		goto bail_disable_ch1;
  	}
  
  
  	/* device 19, func 0, Error injection */
  	einj = pci_get_device_func(PCI_VENDOR_ID_INTEL,
  				    PCI_DEVICE_ID_INTEL_5100_19, 0);
  	if (!einj) {
  		ret = -ENODEV;
  		goto bail_einj;
  	}
  
  	rc = pci_enable_device(einj);
  	if (rc < 0) {
  		ret = rc;
  		goto bail_disable_einj;
  	}
  
  
  	mci->pdev = &pdev->dev;
  
  	priv = mci->pvt_info;
  	priv->ranksperchan = ranksperch;
  	priv->mc = pdev;
  	priv->ch0mm = ch0mm;
  	priv->ch1mm = ch1mm;
  	priv->einj = einj;
  
  	INIT_DELAYED_WORK(&(priv->i5100_scrubbing), i5100_refresh_scrubbing);
  
  	/* If scrubbing was already enabled by the bios, start maintaining it */
  	pci_read_config_dword(pdev, I5100_MC, &dw);
  	if (i5100_mc_scrben(dw)) {
  		priv->scrub_enable = 1;
  		schedule_delayed_work(&(priv->i5100_scrubbing),
  				      I5100_SCRUB_REFRESH_RATE);
  	}
  
  	i5100_init_dimm_layout(pdev, mci);
  	i5100_init_interleaving(pdev, mci);
  
  	mci->mtype_cap = MEM_FLAG_FB_DDR2;
  	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
  	mci->edac_cap = EDAC_FLAG_SECDED;
  	mci->mod_name = "i5100_edac.c";
  	mci->mod_ver = "not versioned";
  	mci->ctl_name = "i5100";
  	mci->dev_name = pci_name(pdev);
  	mci->ctl_page_to_phys = NULL;
  
  	mci->edac_check = i5100_check_error;
  	mci->set_sdram_scrub_rate = i5100_set_scrub_rate;
  	mci->get_sdram_scrub_rate = i5100_get_scrub_rate;
  
  	priv->inject_channel = 0;
  	priv->inject_hlinesel = 0;
  	priv->inject_deviceptr1 = 0;
  	priv->inject_deviceptr2 = 0;
  	priv->inject_eccmask1 = 0;
  	priv->inject_eccmask2 = 0;
  
  	i5100_init_csrows(mci);
  
  	/* this strange construction seems to be in every driver, dunno why */
  	switch (edac_op_state) {
  	case EDAC_OPSTATE_POLL:
  	case EDAC_OPSTATE_NMI:
  		break;
  	default:
  		edac_op_state = EDAC_OPSTATE_POLL;
  		break;
  	}
  
  	if (edac_mc_add_mc(mci)) {
  		ret = -ENODEV;
  		goto bail_scrub;
  	}
  
  	i5100_setup_debugfs(mci);
  
  	return ret;
  
  bail_scrub:
  	priv->scrub_enable = 0;
  	cancel_delayed_work_sync(&(priv->i5100_scrubbing));
  	edac_mc_free(mci);
  
  bail_disable_einj:
  	pci_disable_device(einj);
  
  bail_einj:
  	pci_dev_put(einj);
  
  bail_disable_ch1:
  	pci_disable_device(ch1mm);
  
  bail_ch1:
  	pci_dev_put(ch1mm);
  
  bail_disable_ch0:
  	pci_disable_device(ch0mm);
  
  bail_ch0:
  	pci_dev_put(ch0mm);
  
  bail_pdev:
  	pci_disable_device(pdev);
  
  bail:
  	return ret;
  }
  
  static void i5100_remove_one(struct pci_dev *pdev)
  {
  	struct mem_ctl_info *mci;
  	struct i5100_priv *priv;
  
  	mci = edac_mc_del_mc(&pdev->dev);
  
  	if (!mci)
  		return;
  
  	priv = mci->pvt_info;
  
  	debugfs_remove_recursive(priv->debugfs);
  
  	priv->scrub_enable = 0;
  	cancel_delayed_work_sync(&(priv->i5100_scrubbing));
  
  	pci_disable_device(pdev);
  	pci_disable_device(priv->ch0mm);
  	pci_disable_device(priv->ch1mm);
  	pci_disable_device(priv->einj);
  	pci_dev_put(priv->ch0mm);
  	pci_dev_put(priv->ch1mm);
  	pci_dev_put(priv->einj);
  
  	edac_mc_free(mci);
  }
  
  static const struct pci_device_id i5100_pci_tbl[] = {
  	/* Device 16, Function 0, Channel 0 Memory Map, Error Flag/Mask, ... */
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5100_16) },
  	{ 0, }
  };
  MODULE_DEVICE_TABLE(pci, i5100_pci_tbl);
  
  static struct pci_driver i5100_driver = {
  	.name = KBUILD_BASENAME,
  	.probe = i5100_init_one,
  	.remove = i5100_remove_one,
  	.id_table = i5100_pci_tbl,
  };
  
  static int __init i5100_init(void)
  {
  	int pci_rc;
  
  	i5100_debugfs = debugfs_create_dir("i5100_edac", NULL);
  
  	pci_rc = pci_register_driver(&i5100_driver);
  	return (pci_rc < 0) ? pci_rc : 0;
  }
  
  static void __exit i5100_exit(void)
  {
  	debugfs_remove(i5100_debugfs);
  
  	pci_unregister_driver(&i5100_driver);
  }
  
  module_init(i5100_init);
  module_exit(i5100_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR
      ("Arthur Jones <ajones@riverbed.com>");
  MODULE_DESCRIPTION("MC Driver for Intel I5100 memory controllers");