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path: root/drivers/edac/i3200_edac.c
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/*
 * Intel 3200/3210 Memory Controller kernel module
 * Copyright (C) 2008-2009 Akamai Technologies, Inc.
 * Portions by Hitoshi Mitake <h.mitake@gmail.com>.
 *
 * This file may be distributed under the terms of the
 * GNU General Public License.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/edac.h>
#include <linux/io.h>
#include "edac_core.h"

#define I3200_REVISION        "1.1"

#define EDAC_MOD_STR        "i3200_edac"

#define PCI_DEVICE_ID_INTEL_3200_HB    0x29f0

#define I3200_RANKS		8
#define I3200_RANKS_PER_CHANNEL	4
#define I3200_CHANNELS		2

/* Intel 3200 register addresses - device 0 function 0 - DRAM Controller */

#define I3200_MCHBAR_LOW	0x48	/* MCH Memory Mapped Register BAR */
#define I3200_MCHBAR_HIGH	0x4c
#define I3200_MCHBAR_MASK	0xfffffc000ULL	/* bits 35:14 */
#define I3200_MMR_WINDOW_SIZE	16384

#define I3200_TOM		0xa0	/* Top of Memory (16b)
		 *
		 * 15:10 reserved
		 *  9:0  total populated physical memory
		 */
#define I3200_TOM_MASK		0x3ff	/* bits 9:0 */
#define I3200_TOM_SHIFT		26	/* 64MiB grain */

#define I3200_ERRSTS		0xc8	/* Error Status Register (16b)
		 *
		 * 15    reserved
		 * 14    Isochronous TBWRR Run Behind FIFO Full
		 *       (ITCV)
		 * 13    Isochronous TBWRR Run Behind FIFO Put
		 *       (ITSTV)
		 * 12    reserved
		 * 11    MCH Thermal Sensor Event
		 *       for SMI/SCI/SERR (GTSE)
		 * 10    reserved
		 *  9    LOCK to non-DRAM Memory Flag (LCKF)
		 *  8    reserved
		 *  7    DRAM Throttle Flag (DTF)
		 *  6:2  reserved
		 *  1    Multi-bit DRAM ECC Error Flag (DMERR)
		 *  0    Single-bit DRAM ECC Error Flag (DSERR)
		 */
#define I3200_ERRSTS_UE		0x0002
#define I3200_ERRSTS_CE		0x0001
#define I3200_ERRSTS_BITS	(I3200_ERRSTS_UE | I3200_ERRSTS_CE)


/* Intel  MMIO register space - device 0 function 0 - MMR space */

#define I3200_C0DRB	0x200	/* Channel 0 DRAM Rank Boundary (16b x 4)
		 *
		 * 15:10 reserved
		 *  9:0  Channel 0 DRAM Rank Boundary Address
		 */
#define I3200_C1DRB	0x600	/* Channel 1 DRAM Rank Boundary (16b x 4) */
#define I3200_DRB_MASK	0x3ff	/* bits 9:0 */
#define I3200_DRB_SHIFT	26	/* 64MiB grain */

#define I3200_C0ECCERRLOG	0x280	/* Channel 0 ECC Error Log (64b)
		 *
		 * 63:48 Error Column Address (ERRCOL)
		 * 47:32 Error Row Address (ERRROW)
		 * 31:29 Error Bank Address (ERRBANK)
		 * 28:27 Error Rank Address (ERRRANK)
		 * 26:24 reserved
		 * 23:16 Error Syndrome (ERRSYND)
		 * 15: 2 reserved
		 *    1  Multiple Bit Error Status (MERRSTS)
		 *    0  Correctable Error Status (CERRSTS)
		 */
#define I3200_C1ECCERRLOG		0x680	/* Chan 1 ECC Error Log (64b) */
#define I3200_ECCERRLOG_CE		0x1
#define I3200_ECCERRLOG_UE		0x2
#define I3200_ECCERRLOG_RANK_BITS	0x18000000
#define I3200_ECCERRLOG_RANK_SHIFT	27
#define I3200_ECCERRLOG_SYNDROME_BITS	0xff0000
#define I3200_ECCERRLOG_SYNDROME_SHIFT	16
#define I3200_CAPID0			0xe0	/* P.95 of spec for details */

struct i3200_priv {
	void __iomem *window;
};

static int nr_channels;

#ifndef readq
static inline __u64 readq(const volatile void __iomem *addr)
{
	const volatile u32 __iomem *p = addr;
	u32 low, high;

	low = readl(p);
	high = readl(p + 1);

	return low + ((u64)high << 32);
}
#endif

static int how_many_channels(struct pci_dev *pdev)
{
	unsigned char capid0_8b; /* 8th byte of CAPID0 */

	pci_read_config_byte(pdev, I3200_CAPID0 + 8, &capid0_8b);
	if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
		debugf0("In single channel mode.\n");
		return 1;
	} else {
		debugf0("In dual channel mode.\n");
		return 2;
	}
}

static unsigned long eccerrlog_syndrome(u64 log)
{
	return (log & I3200_ECCERRLOG_SYNDROME_BITS) >>
		I3200_ECCERRLOG_SYNDROME_SHIFT;
}

static int eccerrlog_row(int channel, u64 log)
{
	u64 rank = ((log & I3200_ECCERRLOG_RANK_BITS) >>
		I3200_ECCERRLOG_RANK_SHIFT);
	return rank | (channel * I3200_RANKS_PER_CHANNEL);
}

enum i3200_chips {
	I3200 = 0,
};

struct i3200_dev_info {
	const char *ctl_name;
};

struct i3200_error_info {
	u16 errsts;
	u16 errsts2;
	u64 eccerrlog[I3200_CHANNELS];
};

static const struct i3200_dev_info i3200_devs[] = {
	[I3200] = {
		.ctl_name = "i3200"
	},
};

static struct pci_dev *mci_pdev;
static int i3200_registered = 1;


static void i3200_clear_error_info(struct mem_ctl_info *mci)
{
	struct pci_dev *pdev;

	pdev = to_pci_dev(mci->dev);

	/*
	 * Clear any error bits.
	 * (Yes, we really clear bits by writing 1 to them.)
	 */
	pci_write_bits16(pdev, I3200_ERRSTS, I3200_ERRSTS_BITS,
		I3200_ERRSTS_BITS);
}

static void i3200_get_and_clear_error_info(struct mem_ctl_info *mci,
		struct i3200_error_info *info)
{
	struct pci_dev *pdev;
	struct i3200_priv *priv = mci->pvt_info;
	void __iomem *window = priv->window;

	pdev = to_pci_dev(mci->dev);

	/*
	 * This is a mess because there is no atomic way to read all the
	 * registers at once and the registers can transition from CE being
	 * overwritten by UE.
	 */
	pci_read_config_word(pdev, I3200_ERRSTS, &info->errsts);
	if (!(info->errsts & I3200_ERRSTS_BITS))
		return;

	info->eccerrlog[0] = readq(window + I3200_C0ECCERRLOG);
	if (nr_channels == 2)
		info->eccerrlog[1] = readq(window + I3200_C1ECCERRLOG);

	pci_read_config_word(pdev, I3200_ERRSTS, &info->errsts2);

	/*
	 * If the error is the same for both reads then the first set
	 * of reads is valid.  If there is a change then there is a CE
	 * with no info and the second set of reads is valid and
	 * should be UE info.
	 */
	if ((info->errsts ^ info->errsts2) & I3200_ERRSTS_BITS) {
		info->eccerrlog[0] = readq(window + I3200_C0ECCERRLOG);
		if (nr_channels == 2)
			info->eccerrlog[1] = readq(window + I3200_C1ECCERRLOG);
	}

	i3200_clear_error_info(mci);
}

static void i3200_process_error_info(struct mem_ctl_info *mci,
		struct i3200_error_info *info)
{
	int channel;
	u64 log;

	if (!(info->errsts & I3200_ERRSTS_BITS))
		return;

	if ((info->errsts ^ info->errsts2) & I3200_ERRSTS_BITS) {
		edac_mc_handle_ce_no_info(mci, "UE overwrote CE");
		info->errsts = info->errsts2;
	}

	for (channel = 0; channel < nr_channels; channel++) {
		log = info->eccerrlog[channel];
		if (log & I3200_ECCERRLOG_UE) {
			edac_mc_handle_ue(mci, 0, 0,
				eccerrlog_row(channel, log),
				"i3200 UE");
		} else if (log & I3200_ECCERRLOG_CE) {
			edac_mc_handle_ce(mci, 0, 0,
				eccerrlog_syndrome(log),
				eccerrlog_row(channel, log), 0,="hl opt">;
	return tmp;
}
EXPORT_SYMBOL(strcpy);
#endif

#ifndef __HAVE_ARCH_STRNCPY
/**
 * strncpy - Copy a length-limited, %NUL-terminated string
 * @dest: Where to copy the string to
 * @src: Where to copy the string from
 * @count: The maximum number of bytes to copy
 *
 * The result is not %NUL-terminated if the source exceeds
 * @count bytes.
 *
 * In the case where the length of @src is less than  that  of
 * count, the remainder of @dest will be padded with %NUL.
 *
 */
char *strncpy(char *dest, const char *src, size_t count)
{
	char *tmp = dest;

	while (count) {
		if ((*tmp = *src) != 0)
			src++;
		tmp++;
		count--;
	}
	return dest;
}
EXPORT_SYMBOL(strncpy);
#endif

#ifndef __HAVE_ARCH_STRLCPY
/**
 * strlcpy - Copy a %NUL terminated string into a sized buffer
 * @dest: Where to copy the string to
 * @src: Where to copy the string from
 * @size: size of destination buffer
 *
 * Compatible with *BSD: the result is always a valid
 * NUL-terminated string that fits in the buffer (unless,
 * of course, the buffer size is zero). It does not pad
 * out the result like strncpy() does.
 */
size_t strlcpy(char *dest, const char *src, size_t size)
{
	size_t ret = strlen(src);

	if (size) {
		size_t len = (ret >= size) ? size - 1 : ret;
		memcpy(dest, src, len);
		dest[len] = '\0';
	}
	return ret;
}
EXPORT_SYMBOL(strlcpy);
#endif

#ifndef __HAVE_ARCH_STRCAT
/**
 * strcat - Append one %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 */
#undef strcat
char *strcat(char *dest, const char *src)
{
	char *tmp = dest;

	while (*dest)
		dest++;
	while ((*dest++ = *src++) != '\0')
		;
	return tmp;
}
EXPORT_SYMBOL(strcat);
#endif

#ifndef __HAVE_ARCH_STRNCAT
/**
 * strncat - Append a length-limited, %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 * @count: The maximum numbers of bytes to copy
 *
 * Note that in contrast to strncpy(), strncat() ensures the result is
 * terminated.
 */
char *strncat(char *dest, const char *src, size_t count)
{
	char *tmp = dest;

	if (count) {
		while (*dest)
			dest++;
		while ((*dest++ = *src++) != 0) {
			if (--count == 0) {
				*dest = '\0';
				break;
			}
		}
	}
	return tmp;
}
EXPORT_SYMBOL(strncat);
#endif

#ifndef __HAVE_ARCH_STRLCAT
/**
 * strlcat - Append a length-limited, %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 * @count: The size of the destination buffer.
 */
size_t strlcat(char *dest, const char *src, size_t count)
{
	size_t dsize = strlen(dest);
	size_t len = strlen(src);
	size_t res = dsize + len;

	/* This would be a bug */
	BUG_ON(dsize >= count);

	dest += dsize;
	count -= dsize;
	if (len >= count)
		len = count-1;
	memcpy(dest, src, len);
	dest[len] = 0;
	return res;
}
EXPORT_SYMBOL(strlcat);
#endif

#ifndef __HAVE_ARCH_STRCMP
/**
 * strcmp - Compare two strings
 * @cs: One string
 * @ct: Another string
 */
#undef strcmp
int strcmp(const char *cs, const char *ct)
{
	unsigned char c1, c2;

	while (1) {
		c1 = *cs++;
		c2 = *ct++;
		if (c1 != c2)
			return c1 < c2 ? -1 : 1;
		if (!c1)
			break;
	}
	return 0;
}
EXPORT_SYMBOL(strcmp);
#endif

#ifndef __HAVE_ARCH_STRNCMP
/**
 * strncmp - Compare two length-limited strings
 * @cs: One string
 * @ct: Another string
 * @count: The maximum number of bytes to compare
 */
int strncmp(const char *cs, const char *ct, size_t count)
{
	unsigned char c1, c2;

	while (count) {
		c1 = *cs++;
		c2 = *ct++;
		if (c1 != c2)
			return c1 < c2 ? -1 : 1;
		if (!c1)
			break;
		count--;
	}
	return 0;
}
EXPORT_SYMBOL(strncmp);
#endif

#ifndef __HAVE_ARCH_STRCHR
/**
 * strchr - Find the first occurrence of a character in a string
 * @s: The string to be searched
 * @c: The character to search for
 */
char *strchr(const char *s, int c)
{
	for (; *s != (char)c; ++s)
		if (*s == '\0')
			return NULL;
	return (char *)s;
}
EXPORT_SYMBOL(strchr);
#endif

#ifndef __HAVE_ARCH_STRRCHR
/**
 * strrchr - Find the last occurrence of a character in a string
 * @s: The string to be searched
 * @c: The character to search for
 */
char *strrchr(const char *s, int c)
{
       const char *p = s + strlen(s);
       do {
           if (*p == (char)c)
               return (char *)p;
       } while (--p >= s);
       return NULL;
}
EXPORT_SYMBOL(strrchr);
#endif

#ifndef __HAVE_ARCH_STRNCHR
/**
 * strnchr - Find a character in a length limited string
 * @s: The string to be searched
 * @count: The number of characters to be searched
 * @c: The character to search for
 */
char *strnchr(const char *s, size_t count, int c)
{
	for (; count-- && *s != '\0'; ++s)
		if (*s == (char)c)
			return (char *)s;
	return NULL;
}
EXPORT_SYMBOL(strnchr);
#endif

/**
 * skip_spaces - Removes leading whitespace from @str.
 * @str: The string to be stripped.
 *
 * Returns a pointer to the first non-whitespace character in @str.
 */
char *skip_spaces(const char *str)
{
	while (isspace(*str))
		++str;
	return (char *)str;
}
EXPORT_SYMBOL(skip_spaces);

/**
 * strim - Removes leading and trailing whitespace from @s.
 * @s: The string to be stripped.
 *
 * Note that the first trailing whitespace is replaced with a %NUL-terminator
 * in the given string @s. Returns a pointer to the first non-whitespace
 * character in @s.
 */
char *strim(char *s)
{
	size_t size;
	char *end;

	s = skip_spaces(s);
	size = strlen(s);
	if (!size)
		return s;

	end = s + size - 1;
	while (end >= s && isspace(*end))
		end--;
	*(end + 1) = '\0';

	return s;
}
EXPORT_SYMBOL(strim);

#ifndef __HAVE_ARCH_STRLEN
/**
 * strlen - Find the length of a string
 * @s: The string to be sized
 */
size_t strlen(const char *s)
{
	const char *sc;

	for (sc = s; *sc != '\0'; ++sc)
		/* nothing */;
	return sc - s;
}
EXPORT_SYMBOL(strlen);
#endif

#ifndef __HAVE_ARCH_STRNLEN
/**
 * strnlen - Find the length of a length-limited string
 * @s: The string to be sized
 * @count: The maximum number of bytes to search
 */
size_t strnlen(const char *s, size_t count)
{
	const char *sc;

	for (sc = s; count-- && *sc != '\0'; ++sc)
		/* nothing */;
	return sc - s;
}
EXPORT_SYMBOL(strnlen);
#endif

#ifndef __HAVE_ARCH_STRSPN
/**
 * strspn - Calculate the length of the initial substring of @s which only contain letters in @accept
 * @s: The string to be searched
 * @accept: The string to search for
 */
size_t strspn(const char *s, const char *accept)
{
	const char *p;
	const char *a;
	size_t count = 0;

	for (p = s; *p != '\0'; ++p) {
		for (a = accept; *a != '\0'; ++a) {
			if (*p == *a)
				break;
		}
		if (*a == '\0')
			return count;
		++count;
	}
	return count;
}

EXPORT_SYMBOL(strspn);
#endif

#ifndef __HAVE_ARCH_STRCSPN
/**
 * strcspn - Calculate the length of the initial substring of @s which does not contain letters in @reject
 * @s: The string to be searched
 * @reject: The string to avoid
 */
size_t strcspn(const char *s, const char *reject)
{
	const char *p;
	const char *r;
	size_t count = 0;

	for (p = s; *p != '\0'; ++p) {
		for (r = reject; *r != '\0'; ++r) {
			if (*p == *r)
				return count;
		}
		++count;
	}
	return count;
}
EXPORT_SYMBOL(strcspn);
#endif

#ifndef __HAVE_ARCH_STRPBRK
/**
 * strpbrk - Find the first occurrence of a set of characters
 * @cs: The string to be searched
 * @ct: The characters to search for
 */
char *strpbrk(const char *cs, const char *ct)
{
	const char *sc1, *sc2;

	for (sc1 = cs; *sc1 != '\0'; ++sc1) {
		for (sc2 = ct; *sc2 != '\0'; ++sc2) {
			if (*sc1 == *sc2)
				return (char *)sc1;
		}
	}
	return NULL;
}
EXPORT_SYMBOL(strpbrk);
#endif

#ifndef __HAVE_ARCH_STRSEP
/**
 * strsep - Split a string into tokens
 * @s: The string to be searched
 * @ct: The characters to search for
 *
 * strsep() updates @s to point after the token, ready for the next call.
 *
 * It returns empty tokens, too, behaving exactly like the libc function
 * of that name. In fact, it was stolen from glibc2 and de-fancy-fied.
 * Same semantics, slimmer shape. ;)
 */
char *strsep(char **s, const char *ct)
{
	char *sbegin = *s;
	char *end;

	if (sbegin == NULL)
		return NULL;

	end = strpbrk(sbegin, ct);
	if (end)
		*end++ = '\0';
	*s = end;
	return sbegin;
}
EXPORT_SYMBOL(strsep);
#endif

/**
 * sysfs_streq - return true if strings are equal, modulo trailing newline
 * @s1: one string
 * @s2: another string
 *
 * This routine returns true iff two strings are equal, treating both
 * NUL and newline-then-NUL as equivalent string terminations.  It's
 * geared for use with sysfs input strings, which generally terminate
 * with newlines but are compared against values without newlines.
 */
bool sysfs_streq(const char *s1, const char *s2)
{
	while (*s1 && *s1 == *s2) {
		s1++;
		s2++;
	}

	if (*s1 == *s2)
		return true;
	if (!*s1 && *s2 == '\n' && !s2[1])
		return true;
	if (*s1 == '\n' && !s1[1] && !*s2)
		return true;
	return false;
}
EXPORT_SYMBOL(sysfs_streq);

#ifndef __HAVE_ARCH_MEMSET
/**
 * memset - Fill a region of memory with the given value
 * @s: Pointer to the start of the area.
 * @c: The byte to fill the area with
 * @count: The size of the area.
 *
 * Do not use memset() to access IO space, use memset_io() instead.
 */
void *memset(void *s, int c, size_t count)
{
	char *xs = s;

	while (count--)
		*xs++ = c;
	return s;
}
EXPORT_SYMBOL(memset);
#endif

#ifndef __HAVE_ARCH_MEMCPY
/**
 * memcpy - Copy one area of memory to another
 * @dest: Where to copy to
 * @src: Where to copy from
 * @count: The size of the area.
 *
 * You should not use this function to access IO space, use memcpy_toio()
 * or memcpy_fromio() instead.
 */
void *memcpy(void *dest, const void *src, size_t count)
{
	char *tmp = dest;
	const char *s = src;

	while (count--)
		*tmp++ = *s++;
	return dest;
}
EXPORT_SYMBOL(memcpy);
#endif

#ifndef __HAVE_ARCH_MEMMOVE
/**
 * memmove - Copy one area of memory to another
 * @dest: Where to copy to
 * @src: Where to copy from
 * @count: The size of the area.
 *
 * Unlike memcpy(), memmove() copes with overlapping areas.
 */
void *memmove(void *dest, const void *src, size_t count)
{
	char *tmp;
	const char *s;

	if (dest <= src) {
		tmp = dest;
		s = src;
		while (count--)
			*tmp++ = *s++;
	} else {
		tmp = dest;
		tmp += count;
		s = src;
		s += count;
		while (count--)
			*--tmp = *--s;
	}
	return dest;
}
EXPORT_SYMBOL(memmove);
#endif

#ifndef __HAVE_ARCH_MEMCMP
/**
 * memcmp - Compare two areas of memory
 * @cs: One area of memory
 * @ct: Another area of memory
 * @count: The size of the area.
 */
#undef memcmp
int memcmp(const void *cs, const void *ct, size_t count)
{
	const unsigned char *su1, *su2;
	int res = 0;

	for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
		if ((res = *su1 - *su2) != 0)
			break;
	return res;
}
EXPORT_SYMBOL(memcmp);
#endif

#ifndef __HAVE_ARCH_MEMSCAN
/**
 * memscan - Find a character in an area of memory.
 * @addr: The memory area
 * @c: The byte to search for
 * @size: The size of the area.
 *
 * returns the address of the first occurrence of @c, or 1 byte past
 * the area if @c is not found
 */
void *memscan(void *addr, int c, size_t size)
{
	unsigned char *p = addr;

	while (size) {
		if (*p == c)
			return (void *)p;
		p++;
		size--;
	}
  	return (void *)p;
}
EXPORT_SYMBOL(memscan);
#endif

#ifndef __HAVE_ARCH_STRSTR
/**
 * strstr - Find the first substring in a %NUL terminated string
 * @s1: The string to be searched
 * @s2: The string to search for
 */
char *strstr(const char *s1, const char *s2)
{
	size_t l1, l2;

	l2 = strlen(s2);
	if (!l2)
		return (char *)s1;
	l1 = strlen(s1);
	while (l1 >= l2) {
		l1--;
		if (!memcmp(s1, s2, l2))
			return (char *)s1;
		s1++;
	}
	return NULL;
}
EXPORT_SYMBOL(strstr);
#endif

#ifndef __HAVE_ARCH_STRNSTR
/**
 * strnstr - Find the first substring in a length-limited string
 * @s1: The string to be searched
 * @s2: The string to search for
 * @len: the maximum number of characters to search
 */
char *strnstr(const char *s1, const char *s2, size_t len)
{
	size_t l2;

	l2 = strlen(s2);
	if (!l2)
		return (char *)s1;
	while (len >= l2) {
		len--;
		if (!memcmp(s1, s2, l2))
			return (char *)s1;
		s1++;
	}
	return NULL;
}
EXPORT_SYMBOL(strnstr);
#endif

#ifndef __HAVE_ARCH_MEMCHR
/**
 * memchr - Find a character in an area of memory.
 * @s: The memory area
 * @c: The byte to search for
 * @n: The size of the area.
 *
 * returns the address of the first occurrence of @c, or %NULL
 * if @c is not found
 */
void *memchr(const void *s, int c, size_t n)
{
	const unsigned char *p = s;
	while (n-- != 0) {
        	if ((unsigned char)c == *p++) {
			return (void *)(p - 1);
		}
	}
	return NULL;
}
EXPORT_SYMBOL(memchr);
#endif