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/*
* AMD64 class Memory Controller kernel module
*
* Copyright ( c ) 2009 SoftwareBitMaker .
* Copyright ( c ) 2009 Advanced Micro Devices , Inc .
*
* This file may be distributed under the terms of the
* GNU General Public License .
*
* Originally Written by Thayne Harbaugh
*
* Changes by Douglas " norsk " Thompson < dougthompson @ xmission . com > :
* - K8 CPU Revision D and greater support
*
* Changes by Dave Peterson < dsp @ llnl . gov > < dave_peterson @ pobox . com > :
* - Module largely rewritten , with new ( and hopefully correct )
* code for dealing with node and chip select interleaving ,
* various code cleanup , and bug fixes
* - Added support for memory hoisting using DRAM hole address
* register
*
* Changes by Douglas " norsk " Thompson < dougthompson @ xmission . com > :
* - K8 Rev ( 1207 ) revision support added , required Revision
* specific mini - driver code to support Rev F as well as
* prior revisions
*
* Changes by Douglas " norsk " Thompson < dougthompson @ xmission . com > :
* - Family 10 h revision support added . New PCI Device IDs ,
* indicating new changes . Actual registers modified
* were slight , less than the Rev E to Rev F transition
* but changing the PCI Device ID was the proper thing to
* do , as it provides for almost automactic family
* detection . The mods to Rev F required more family
* information detection .
*
* Changes / Fixes by Borislav Petkov < borislav . petkov @ amd . com > :
* - misc fixes and code cleanups
*
* This module is based on the following documents
* ( available from http : //www.amd.com/):
*
* Title : BIOS and Kernel Developer ' s Guide for AMD Athlon 64 and AMD
* Opteron Processors
* AMD publication # : 26094
* ` Revision : 3.26
*
* Title : BIOS and Kernel Developer ' s Guide for AMD NPT Family 0F h
* Processors
* AMD publication # : 32559
* Revision : 3.00
* Issue Date : May 2006
*
* Title : BIOS and Kernel Developer ' s Guide ( BKDG ) For AMD Family 10 h
* Processors
* AMD publication # : 31116
* Revision : 3.00
* Issue Date : September 07 , 2007
*
* Sections in the first 2 documents are no longer in sync with each other .
* The Family 10 h BKDG was totally re - written from scratch with a new
* presentation model .
* Therefore , comments that refer to a Document section might be off .
*/
# include <linux/module.h>
# include <linux/ctype.h>
# include <linux/init.h>
# include <linux/pci.h>
# include <linux/pci_ids.h>
# include <linux/slab.h>
# include <linux/mmzone.h>
# include <linux/edac.h>
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# include <asm/msr.h>
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# include "edac_core.h"
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# include "mce_amd.h"
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# define amd64_debug(fmt, arg...) \
edac_printk ( KERN_DEBUG , " amd64 " , fmt , # # arg )
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# define amd64_info(fmt, arg...) \
edac_printk ( KERN_INFO , " amd64 " , fmt , # # arg )
# define amd64_notice(fmt, arg...) \
edac_printk ( KERN_NOTICE , " amd64 " , fmt , # # arg )
# define amd64_warn(fmt, arg...) \
edac_printk ( KERN_WARNING , " amd64 " , fmt , # # arg )
# define amd64_err(fmt, arg...) \
edac_printk ( KERN_ERR , " amd64 " , fmt , # # arg )
# define amd64_mc_warn(mci, fmt, arg...) \
edac_mc_chipset_printk ( mci , KERN_WARNING , " amd64 " , fmt , # # arg )
# define amd64_mc_err(mci, fmt, arg...) \
edac_mc_chipset_printk ( mci , KERN_ERR , " amd64 " , fmt , # # arg )
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/*
* Throughout the comments in this code , the following terms are used :
*
* SysAddr , DramAddr , and InputAddr
*
* These terms come directly from the amd64 documentation
* ( AMD publication # 26094 ) . They are defined as follows :
*
* SysAddr :
* This is a physical address generated by a CPU core or a device
* doing DMA . If generated by a CPU core , a SysAddr is the result of
* a virtual to physical address translation by the CPU core ' s address
* translation mechanism ( MMU ) .
*
* DramAddr :
* A DramAddr is derived from a SysAddr by subtracting an offset that
* depends on which node the SysAddr maps to and whether the SysAddr
* is within a range affected by memory hoisting . The DRAM Base
* ( section 3.4 .4 .1 ) and DRAM Limit ( section 3.4 .4 .2 ) registers
* determine which node a SysAddr maps to .
*
* If the DRAM Hole Address Register ( DHAR ) is enabled and the SysAddr
* is within the range of addresses specified by this register , then
* a value x from the DHAR is subtracted from the SysAddr to produce a
* DramAddr . Here , x represents the base address for the node that
* the SysAddr maps to plus an offset due to memory hoisting . See
* section 3.4 .8 and the comments in amd64_get_dram_hole_info ( ) and
* sys_addr_to_dram_addr ( ) below for more information .
*
* If the SysAddr is not affected by the DHAR then a value y is
* subtracted from the SysAddr to produce a DramAddr . Here , y is the
* base address for the node that the SysAddr maps to . See section
* 3.4 .4 and the comments in sys_addr_to_dram_addr ( ) below for more
* information .
*
* InputAddr :
* A DramAddr is translated to an InputAddr before being passed to the
* memory controller for the node that the DramAddr is associated
* with . The memory controller then maps the InputAddr to a csrow .
* If node interleaving is not in use , then the InputAddr has the same
* value as the DramAddr . Otherwise , the InputAddr is produced by
* discarding the bits used for node interleaving from the DramAddr .
* See section 3.4 .4 for more information .
*
* The memory controller for a given node uses its DRAM CS Base and
* DRAM CS Mask registers to map an InputAddr to a csrow . See
* sections 3.5 .4 and 3.5 .5 for more information .
*/
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# define EDAC_AMD64_VERSION "v3.3.0"
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# define EDAC_MOD_STR "amd64_edac"
/* Extended Model from CPUID, for CPU Revision numbers */
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# define K8_REV_D 1
# define K8_REV_E 2
# define K8_REV_F 4
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/* Hardware limit on ChipSelect rows per MC and processors per system */
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# define NUM_CHIPSELECTS 8
# define DRAM_RANGES 8
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# define ON true
# define OFF false
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/*
* Create a contiguous bitmask starting at bit position @ lo and ending at
* position @ hi . For example
*
* GENMASK ( 21 , 39 ) gives us the 64 bit vector 0x000000ffffe00000 .
*/
# define GENMASK(lo, hi) (((1ULL << ((hi) - (lo) + 1)) - 1) << (lo))
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/*
* PCI - defined configuration space registers
*/
/*
* Function 1 - Address Map
*/
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# define DRAM_BASE_LO 0x40
# define DRAM_LIMIT_LO 0x44
# define dram_intlv_en(pvt, i) ((pvt->ranges[i].base.lo >> 8) & 0x7)
# define dram_rw(pvt, i) (pvt->ranges[i].base.lo & 0x3)
# define dram_intlv_sel(pvt, i) ((pvt->ranges[i].lim.lo >> 8) & 0x7)
# define dram_dst_node(pvt, i) (pvt->ranges[i].lim.lo & 0x7)
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# define DHAR 0xf0
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# define dhar_valid(pvt) ((pvt)->dhar & BIT(0))
# define dhar_mem_hoist_valid(pvt) ((pvt)->dhar & BIT(1))
# define dhar_base(pvt) ((pvt)->dhar & 0xff000000)
# define k8_dhar_offset(pvt) (((pvt)->dhar & 0x0000ff00) << 16)
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/* NOTE: Extra mask bit vs K8 */
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# define f10_dhar_offset(pvt) (((pvt)->dhar & 0x0000ff80) << 16)
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# define DCT_CFG_SEL 0x10C
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# define DRAM_BASE_HI 0x140
# define DRAM_LIMIT_HI 0x144
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/*
* Function 2 - DRAM controller
*/
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# define DCSB0 0x40
# define DCSB1 0x140
# define DCSB_CS_ENABLE BIT(0)
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# define DCSM0 0x60
# define DCSM1 0x160
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# define csrow_enabled(i, dct, pvt) ((pvt)->csels[(dct)].csbases[(i)] & DCSB_CS_ENABLE)
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# define DBAM0 0x80
# define DBAM1 0x180
/* Extract the DIMM 'type' on the i'th DIMM from the DBAM reg value passed */
# define DBAM_DIMM(i, reg) ((((reg) >> (4*i))) & 0xF)
# define DBAM_MAX_VALUE 11
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# define DCLR0 0x90
# define DCLR1 0x190
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# define REVE_WIDTH_128 BIT(16)
# define F10_WIDTH_128 BIT(11)
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# define DCHR0 0x94
# define DCHR1 0x194
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# define DDR3_MODE BIT(8)
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# define DCT_SEL_LO 0x110
# define dct_sel_baseaddr(pvt) ((pvt)->dct_sel_lo & 0xFFFFF800)
# define dct_sel_interleave_addr(pvt) (((pvt)->dct_sel_lo >> 6) & 0x3)
# define dct_high_range_enabled(pvt) ((pvt)->dct_sel_lo & BIT(0))
# define dct_interleave_enabled(pvt) ((pvt)->dct_sel_lo & BIT(2))
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# define dct_ganging_enabled(pvt) ((boot_cpu_data.x86 == 0x10) && ((pvt)->dct_sel_lo & BIT(4)))
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# define dct_data_intlv_enabled(pvt) ((pvt)->dct_sel_lo & BIT(5))
# define dct_dram_enabled(pvt) ((pvt)->dct_sel_lo & BIT(8))
# define dct_memory_cleared(pvt) ((pvt)->dct_sel_lo & BIT(10))
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# define DCT_SEL_HI 0x114
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/*
* Function 3 - Misc Control
*/
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# define NBCTL 0x40
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# define NBCFG 0x44
# define NBCFG_CHIPKILL BIT(23)
# define NBCFG_ECC_ENABLE BIT(22)
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# define K8_NBSL 0x48
/* Family F10h: Normalized Extended Error Codes */
# define F10_NBSL_EXT_ERR_RES 0x0
# define F10_NBSL_EXT_ERR_ECC 0x8
/* Next two are overloaded values */
# define F10_NBSL_EXT_ERR_LINK_PROTO 0xB
# define F10_NBSL_EXT_ERR_L3_PROTO 0xB
# define F10_NBSL_EXT_ERR_NB_ARRAY 0xC
# define F10_NBSL_EXT_ERR_DRAM_PARITY 0xD
# define F10_NBSL_EXT_ERR_LINK_RETRY 0xE
/* Next two are overloaded values */
# define F10_NBSL_EXT_ERR_GART_WALK 0xF
# define F10_NBSL_EXT_ERR_DEV_WALK 0xF
/* 0x10 to 0x1B: Reserved */
# define F10_NBSL_EXT_ERR_L3_DATA 0x1C
# define F10_NBSL_EXT_ERR_L3_TAG 0x1D
# define F10_NBSL_EXT_ERR_L3_LRU 0x1E
/* K8: Normalized Extended Error Codes */
# define K8_NBSL_EXT_ERR_ECC 0x0
# define K8_NBSL_EXT_ERR_CRC 0x1
# define K8_NBSL_EXT_ERR_SYNC 0x2
# define K8_NBSL_EXT_ERR_MST 0x3
# define K8_NBSL_EXT_ERR_TGT 0x4
# define K8_NBSL_EXT_ERR_GART 0x5
# define K8_NBSL_EXT_ERR_RMW 0x6
# define K8_NBSL_EXT_ERR_WDT 0x7
# define K8_NBSL_EXT_ERR_CHIPKILL_ECC 0x8
# define K8_NBSL_EXT_ERR_DRAM_PARITY 0xD
/*
* The following are for BUS type errors AFTER values have been normalized by
* shifting right
*/
# define K8_NBSL_PP_SRC 0x0
# define K8_NBSL_PP_RES 0x1
# define K8_NBSL_PP_OBS 0x2
# define K8_NBSL_PP_GENERIC 0x3
# define EXTRACT_ERR_CPU_MAP(x) ((x) & 0xF)
# define K8_NBEAL 0x50
# define K8_NBEAH 0x54
# define K8_SCRCTRL 0x58
# define F10_NB_CFG_LOW 0x88
# define F10_ONLINE_SPARE 0xB0
# define F10_ONLINE_SPARE_SWAPDONE0(x) ((x) & BIT(1))
# define F10_ONLINE_SPARE_SWAPDONE1(x) ((x) & BIT(3))
# define F10_ONLINE_SPARE_BADDRAM_CS0(x) (((x) >> 4) & 0x00000007)
# define F10_ONLINE_SPARE_BADDRAM_CS1(x) (((x) >> 8) & 0x00000007)
# define F10_NB_ARRAY_ADDR 0xB8
# define F10_NB_ARRAY_DRAM_ECC 0x80000000
/* Bits [2:1] are used to select 16-byte section within a 64-byte cacheline */
# define SET_NB_ARRAY_ADDRESS(section) (((section) & 0x3) << 1)
# define F10_NB_ARRAY_DATA 0xBC
# define SET_NB_DRAM_INJECTION_WRITE(word, bits) \
( BIT ( ( ( word ) & 0xF ) + 20 ) | \
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BIT ( 17 ) | bits )
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# define SET_NB_DRAM_INJECTION_READ(word, bits) \
( BIT ( ( ( word ) & 0xF ) + 20 ) | \
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BIT ( 16 ) | bits )
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# define K8_NBCAP 0xE8
# define K8_NBCAP_CORES (BIT(12)|BIT(13))
# define K8_NBCAP_CHIPKILL BIT(4)
# define K8_NBCAP_SECDED BIT(3)
# define K8_NBCAP_DCT_DUAL BIT(0)
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# define EXT_NB_MCA_CFG 0x180
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/* MSRs */
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# define K8_MSR_MCGCTL_NBE BIT(4)
# define K8_MSR_MC4CTL 0x0410
# define K8_MSR_MC4STAT 0x0411
# define K8_MSR_MC4ADDR 0x0412
/* AMD sets the first MC device at device ID 0x18. */
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static inline int get_node_id ( struct pci_dev * pdev )
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{
return PCI_SLOT ( pdev - > devfn ) - 0x18 ;
}
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enum amd_families {
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K8_CPUS = 0 ,
F10_CPUS ,
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F15_CPUS ,
NUM_FAMILIES ,
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} ;
/* Error injection control structure */
struct error_injection {
u32 section ;
u32 word ;
u32 bit_map ;
} ;
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/* low and high part of PCI config space regs */
struct reg_pair {
u32 lo , hi ;
} ;
/*
* See F1x [ 1 , 0 ] [ 7 C : 40 ] DRAM Base / Limit Registers
*/
struct dram_range {
struct reg_pair base ;
struct reg_pair lim ;
} ;
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/* A DCT chip selects collection */
struct chip_select {
u32 csbases [ NUM_CHIPSELECTS ] ;
u8 b_cnt ;
u32 csmasks [ NUM_CHIPSELECTS ] ;
u8 m_cnt ;
} ;
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struct amd64_pvt {
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struct low_ops * ops ;
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/* pci_device handles which we utilize */
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struct pci_dev * F1 , * F2 , * F3 ;
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int mc_node_id ; /* MC index of this MC node */
int ext_model ; /* extended model value of this node */
int channel_count ;
/* Raw registers */
u32 dclr0 ; /* DRAM Configuration Low DCT0 reg */
u32 dclr1 ; /* DRAM Configuration Low DCT1 reg */
u32 dchr0 ; /* DRAM Configuration High DCT0 reg */
u32 dchr1 ; /* DRAM Configuration High DCT1 reg */
u32 nbcap ; /* North Bridge Capabilities */
u32 nbcfg ; /* F10 North Bridge Configuration */
u32 ext_nbcfg ; /* Extended F10 North Bridge Configuration */
u32 dhar ; /* DRAM Hoist reg */
u32 dbam0 ; /* DRAM Base Address Mapping reg for DCT0 */
u32 dbam1 ; /* DRAM Base Address Mapping reg for DCT1 */
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/* one for each DCT */
struct chip_select csels [ 2 ] ;
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/* DRAM base and limit pairs F1x[78,70,68,60,58,50,48,40] */
struct dram_range ranges [ DRAM_RANGES ] ;
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u64 top_mem ; /* top of memory below 4GB */
u64 top_mem2 ; /* top of memory above 4GB */
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u32 dct_sel_lo ; /* DRAM Controller Select Low */
u32 dct_sel_hi ; /* DRAM Controller Select High */
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u32 online_spare ; /* On-Line spare Reg */
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/* x4 or x8 syndromes in use */
u8 syn_type ;
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/* place to store error injection parameters prior to issue */
struct error_injection injection ;
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/* DCT per-family scrubrate setting */
u32 min_scrubrate ;
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/* family name this instance is running on */
const char * ctl_name ;
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} ;
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static inline u64 get_dram_base ( struct amd64_pvt * pvt , unsigned i )
{
u64 addr = ( ( u64 ) pvt - > ranges [ i ] . base . lo & 0xffff0000 ) < < 8 ;
if ( boot_cpu_data . x86 = = 0xf )
return addr ;
return ( ( ( u64 ) pvt - > ranges [ i ] . base . hi & 0x000000ff ) < < 40 ) | addr ;
}
static inline u64 get_dram_limit ( struct amd64_pvt * pvt , unsigned i )
{
u64 lim = ( ( ( u64 ) pvt - > ranges [ i ] . lim . lo & 0xffff0000 ) < < 8 ) | 0x00ffffff ;
if ( boot_cpu_data . x86 = = 0xf )
return lim ;
return ( ( ( u64 ) pvt - > ranges [ i ] . lim . hi & 0x000000ff ) < < 40 ) | lim ;
}
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/*
* per - node ECC settings descriptor
*/
struct ecc_settings {
u32 old_nbctl ;
bool nbctl_valid ;
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struct flags {
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unsigned long nb_mce_enable : 1 ;
unsigned long nb_ecc_prev : 1 ;
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} flags ;
} ;
extern const char * tt_msgs [ 4 ] ;
extern const char * ll_msgs [ 4 ] ;
extern const char * rrrr_msgs [ 16 ] ;
extern const char * to_msgs [ 2 ] ;
extern const char * pp_msgs [ 4 ] ;
extern const char * ii_msgs [ 4 ] ;
extern const char * htlink_msgs [ 8 ] ;
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# ifdef CONFIG_EDAC_DEBUG
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# define NUM_DBG_ATTRS 5
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# else
# define NUM_DBG_ATTRS 0
# endif
# ifdef CONFIG_EDAC_AMD64_ERROR_INJECTION
# define NUM_INJ_ATTRS 5
# else
# define NUM_INJ_ATTRS 0
# endif
extern struct mcidev_sysfs_attribute amd64_dbg_attrs [ NUM_DBG_ATTRS ] ,
amd64_inj_attrs [ NUM_INJ_ATTRS ] ;
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/*
* Each of the PCI Device IDs types have their own set of hardware accessor
* functions and per device encoding / decoding logic .
*/
struct low_ops {
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int ( * early_channel_count ) ( struct amd64_pvt * pvt ) ;
u64 ( * get_error_address ) ( struct mem_ctl_info * mci ,
struct err_regs * info ) ;
void ( * read_dram_ctl_register ) ( struct amd64_pvt * pvt ) ;
void ( * map_sysaddr_to_csrow ) ( struct mem_ctl_info * mci ,
struct err_regs * info , u64 SystemAddr ) ;
int ( * dbam_to_cs ) ( struct amd64_pvt * pvt , int cs_mode ) ;
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int ( * read_dct_pci_cfg ) ( struct amd64_pvt * pvt , int offset ,
u32 * val , const char * func ) ;
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} ;
struct amd64_family_type {
const char * ctl_name ;
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u16 f1_id , f3_id ;
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struct low_ops ops ;
} ;
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int __amd64_write_pci_cfg_dword ( struct pci_dev * pdev , int offset ,
u32 val , const char * func ) ;
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# define amd64_read_pci_cfg(pdev, offset, val) \
__amd64_read_pci_cfg_dword ( pdev , offset , val , __func__ )
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# define amd64_write_pci_cfg(pdev, offset, val) \
__amd64_write_pci_cfg_dword ( pdev , offset , val , __func__ )
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# define amd64_read_dct_pci_cfg(pvt, offset, val) \
pvt - > ops - > read_dct_pci_cfg ( pvt , offset , val , __func__ )
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/*
* For future CPU versions , verify the following as new ' slow ' rates appear and
* modify the necessary skip values for the supported CPU .
*/
# define K8_MIN_SCRUB_RATE_BITS 0x0
# define F10_MIN_SCRUB_RATE_BITS 0x5
int amd64_get_dram_hole_info ( struct mem_ctl_info * mci , u64 * hole_base ,
u64 * hole_offset , u64 * hole_size ) ;