linux/drivers/edac/amd64_edac.h
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   1/*
   2 * AMD64 class Memory Controller kernel module
   3 *
   4 * Copyright (c) 2009 SoftwareBitMaker.
   5 * Copyright (c) 2009-15 Advanced Micro Devices, Inc.
   6 *
   7 * This file may be distributed under the terms of the
   8 * GNU General Public License.
   9 */
  10
  11#include <linux/module.h>
  12#include <linux/ctype.h>
  13#include <linux/init.h>
  14#include <linux/pci.h>
  15#include <linux/pci_ids.h>
  16#include <linux/slab.h>
  17#include <linux/mmzone.h>
  18#include <linux/edac.h>
  19#include <asm/cpu_device_id.h>
  20#include <asm/msr.h>
  21#include "edac_module.h"
  22#include "mce_amd.h"
  23
  24#define amd64_info(fmt, arg...) \
  25        edac_printk(KERN_INFO, "amd64", fmt, ##arg)
  26
  27#define amd64_warn(fmt, arg...) \
  28        edac_printk(KERN_WARNING, "amd64", "Warning: " fmt, ##arg)
  29
  30#define amd64_err(fmt, arg...) \
  31        edac_printk(KERN_ERR, "amd64", "Error: " fmt, ##arg)
  32
  33#define amd64_mc_warn(mci, fmt, arg...) \
  34        edac_mc_chipset_printk(mci, KERN_WARNING, "amd64", fmt, ##arg)
  35
  36#define amd64_mc_err(mci, fmt, arg...) \
  37        edac_mc_chipset_printk(mci, KERN_ERR, "amd64", fmt, ##arg)
  38
  39/*
  40 * Throughout the comments in this code, the following terms are used:
  41 *
  42 *      SysAddr, DramAddr, and InputAddr
  43 *
  44 *  These terms come directly from the amd64 documentation
  45 * (AMD publication #26094).  They are defined as follows:
  46 *
  47 *     SysAddr:
  48 *         This is a physical address generated by a CPU core or a device
  49 *         doing DMA.  If generated by a CPU core, a SysAddr is the result of
  50 *         a virtual to physical address translation by the CPU core's address
  51 *         translation mechanism (MMU).
  52 *
  53 *     DramAddr:
  54 *         A DramAddr is derived from a SysAddr by subtracting an offset that
  55 *         depends on which node the SysAddr maps to and whether the SysAddr
  56 *         is within a range affected by memory hoisting.  The DRAM Base
  57 *         (section 3.4.4.1) and DRAM Limit (section 3.4.4.2) registers
  58 *         determine which node a SysAddr maps to.
  59 *
  60 *         If the DRAM Hole Address Register (DHAR) is enabled and the SysAddr
  61 *         is within the range of addresses specified by this register, then
  62 *         a value x from the DHAR is subtracted from the SysAddr to produce a
  63 *         DramAddr.  Here, x represents the base address for the node that
  64 *         the SysAddr maps to plus an offset due to memory hoisting.  See
  65 *         section 3.4.8 and the comments in amd64_get_dram_hole_info() and
  66 *         sys_addr_to_dram_addr() below for more information.
  67 *
  68 *         If the SysAddr is not affected by the DHAR then a value y is
  69 *         subtracted from the SysAddr to produce a DramAddr.  Here, y is the
  70 *         base address for the node that the SysAddr maps to.  See section
  71 *         3.4.4 and the comments in sys_addr_to_dram_addr() below for more
  72 *         information.
  73 *
  74 *     InputAddr:
  75 *         A DramAddr is translated to an InputAddr before being passed to the
  76 *         memory controller for the node that the DramAddr is associated
  77 *         with.  The memory controller then maps the InputAddr to a csrow.
  78 *         If node interleaving is not in use, then the InputAddr has the same
  79 *         value as the DramAddr.  Otherwise, the InputAddr is produced by
  80 *         discarding the bits used for node interleaving from the DramAddr.
  81 *         See section 3.4.4 for more information.
  82 *
  83 *         The memory controller for a given node uses its DRAM CS Base and
  84 *         DRAM CS Mask registers to map an InputAddr to a csrow.  See
  85 *         sections 3.5.4 and 3.5.5 for more information.
  86 */
  87
  88#define EDAC_AMD64_VERSION              "3.5.0"
  89#define EDAC_MOD_STR                    "amd64_edac"
  90
  91/* Extended Model from CPUID, for CPU Revision numbers */
  92#define K8_REV_D                        1
  93#define K8_REV_E                        2
  94#define K8_REV_F                        4
  95
  96/* Hardware limit on ChipSelect rows per MC and processors per system */
  97#define NUM_CHIPSELECTS                 8
  98#define DRAM_RANGES                     8
  99#define NUM_CONTROLLERS                 12
 100
 101#define ON true
 102#define OFF false
 103
 104/*
 105 * PCI-defined configuration space registers
 106 */
 107#define PCI_DEVICE_ID_AMD_15H_NB_F1     0x1601
 108#define PCI_DEVICE_ID_AMD_15H_NB_F2     0x1602
 109#define PCI_DEVICE_ID_AMD_15H_M30H_NB_F1 0x141b
 110#define PCI_DEVICE_ID_AMD_15H_M30H_NB_F2 0x141c
 111#define PCI_DEVICE_ID_AMD_15H_M60H_NB_F1 0x1571
 112#define PCI_DEVICE_ID_AMD_15H_M60H_NB_F2 0x1572
 113#define PCI_DEVICE_ID_AMD_16H_NB_F1     0x1531
 114#define PCI_DEVICE_ID_AMD_16H_NB_F2     0x1532
 115#define PCI_DEVICE_ID_AMD_16H_M30H_NB_F1 0x1581
 116#define PCI_DEVICE_ID_AMD_16H_M30H_NB_F2 0x1582
 117#define PCI_DEVICE_ID_AMD_17H_DF_F0     0x1460
 118#define PCI_DEVICE_ID_AMD_17H_DF_F6     0x1466
 119#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F0 0x15e8
 120#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F6 0x15ee
 121#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F0 0x1490
 122#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F6 0x1496
 123#define PCI_DEVICE_ID_AMD_17H_M60H_DF_F0 0x1448
 124#define PCI_DEVICE_ID_AMD_17H_M60H_DF_F6 0x144e
 125#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F0 0x1440
 126#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F6 0x1446
 127#define PCI_DEVICE_ID_AMD_19H_DF_F0     0x1650
 128#define PCI_DEVICE_ID_AMD_19H_DF_F6     0x1656
 129#define PCI_DEVICE_ID_AMD_19H_M10H_DF_F0 0x14ad
 130#define PCI_DEVICE_ID_AMD_19H_M10H_DF_F6 0x14b3
 131#define PCI_DEVICE_ID_AMD_19H_M50H_DF_F0 0x166a
 132#define PCI_DEVICE_ID_AMD_19H_M50H_DF_F6 0x1670
 133
 134/*
 135 * Function 1 - Address Map
 136 */
 137#define DRAM_BASE_LO                    0x40
 138#define DRAM_LIMIT_LO                   0x44
 139
 140/*
 141 * F15 M30h D18F1x2[1C:00]
 142 */
 143#define DRAM_CONT_BASE                  0x200
 144#define DRAM_CONT_LIMIT                 0x204
 145
 146/*
 147 * F15 M30h D18F1x2[4C:40]
 148 */
 149#define DRAM_CONT_HIGH_OFF              0x240
 150
 151#define dram_rw(pvt, i)                 ((u8)(pvt->ranges[i].base.lo & 0x3))
 152#define dram_intlv_sel(pvt, i)          ((u8)((pvt->ranges[i].lim.lo >> 8) & 0x7))
 153#define dram_dst_node(pvt, i)           ((u8)(pvt->ranges[i].lim.lo & 0x7))
 154
 155#define DHAR                            0xf0
 156#define dhar_mem_hoist_valid(pvt)       ((pvt)->dhar & BIT(1))
 157#define dhar_base(pvt)                  ((pvt)->dhar & 0xff000000)
 158#define k8_dhar_offset(pvt)             (((pvt)->dhar & 0x0000ff00) << 16)
 159
 160                                        /* NOTE: Extra mask bit vs K8 */
 161#define f10_dhar_offset(pvt)            (((pvt)->dhar & 0x0000ff80) << 16)
 162
 163#define DCT_CFG_SEL                     0x10C
 164
 165#define DRAM_LOCAL_NODE_BASE            0x120
 166#define DRAM_LOCAL_NODE_LIM             0x124
 167
 168#define DRAM_BASE_HI                    0x140
 169#define DRAM_LIMIT_HI                   0x144
 170
 171
 172/*
 173 * Function 2 - DRAM controller
 174 */
 175#define DCSB0                           0x40
 176#define DCSB1                           0x140
 177#define DCSB_CS_ENABLE                  BIT(0)
 178
 179#define DCSM0                           0x60
 180#define DCSM1                           0x160
 181
 182#define csrow_enabled(i, dct, pvt)      ((pvt)->csels[(dct)].csbases[(i)]     & DCSB_CS_ENABLE)
 183#define csrow_sec_enabled(i, dct, pvt)  ((pvt)->csels[(dct)].csbases_sec[(i)] & DCSB_CS_ENABLE)
 184
 185#define DRAM_CONTROL                    0x78
 186
 187#define DBAM0                           0x80
 188#define DBAM1                           0x180
 189
 190/* Extract the DIMM 'type' on the i'th DIMM from the DBAM reg value passed */
 191#define DBAM_DIMM(i, reg)               ((((reg) >> (4*(i)))) & 0xF)
 192
 193#define DBAM_MAX_VALUE                  11
 194
 195#define DCLR0                           0x90
 196#define DCLR1                           0x190
 197#define REVE_WIDTH_128                  BIT(16)
 198#define WIDTH_128                       BIT(11)
 199
 200#define DCHR0                           0x94
 201#define DCHR1                           0x194
 202#define DDR3_MODE                       BIT(8)
 203
 204#define DCT_SEL_LO                      0x110
 205#define dct_high_range_enabled(pvt)     ((pvt)->dct_sel_lo & BIT(0))
 206#define dct_interleave_enabled(pvt)     ((pvt)->dct_sel_lo & BIT(2))
 207
 208#define dct_ganging_enabled(pvt)        ((boot_cpu_data.x86 == 0x10) && ((pvt)->dct_sel_lo & BIT(4)))
 209
 210#define dct_data_intlv_enabled(pvt)     ((pvt)->dct_sel_lo & BIT(5))
 211#define dct_memory_cleared(pvt)         ((pvt)->dct_sel_lo & BIT(10))
 212
 213#define SWAP_INTLV_REG                  0x10c
 214
 215#define DCT_SEL_HI                      0x114
 216
 217#define F15H_M60H_SCRCTRL               0x1C8
 218#define F17H_SCR_BASE_ADDR              0x48
 219#define F17H_SCR_LIMIT_ADDR             0x4C
 220
 221/*
 222 * Function 3 - Misc Control
 223 */
 224#define NBCTL                           0x40
 225
 226#define NBCFG                           0x44
 227#define NBCFG_CHIPKILL                  BIT(23)
 228#define NBCFG_ECC_ENABLE                BIT(22)
 229
 230/* F3x48: NBSL */
 231#define F10_NBSL_EXT_ERR_ECC            0x8
 232#define NBSL_PP_OBS                     0x2
 233
 234#define SCRCTRL                         0x58
 235
 236#define F10_ONLINE_SPARE                0xB0
 237#define online_spare_swap_done(pvt, c)  (((pvt)->online_spare >> (1 + 2 * (c))) & 0x1)
 238#define online_spare_bad_dramcs(pvt, c) (((pvt)->online_spare >> (4 + 4 * (c))) & 0x7)
 239
 240#define F10_NB_ARRAY_ADDR               0xB8
 241#define F10_NB_ARRAY_DRAM               BIT(31)
 242
 243/* Bits [2:1] are used to select 16-byte section within a 64-byte cacheline  */
 244#define SET_NB_ARRAY_ADDR(section)      (((section) & 0x3) << 1)
 245
 246#define F10_NB_ARRAY_DATA               0xBC
 247#define F10_NB_ARR_ECC_WR_REQ           BIT(17)
 248#define SET_NB_DRAM_INJECTION_WRITE(inj)  \
 249                                        (BIT(((inj.word) & 0xF) + 20) | \
 250                                        F10_NB_ARR_ECC_WR_REQ | inj.bit_map)
 251#define SET_NB_DRAM_INJECTION_READ(inj)  \
 252                                        (BIT(((inj.word) & 0xF) + 20) | \
 253                                        BIT(16) |  inj.bit_map)
 254
 255
 256#define NBCAP                           0xE8
 257#define NBCAP_CHIPKILL                  BIT(4)
 258#define NBCAP_SECDED                    BIT(3)
 259#define NBCAP_DCT_DUAL                  BIT(0)
 260
 261#define EXT_NB_MCA_CFG                  0x180
 262
 263/* MSRs */
 264#define MSR_MCGCTL_NBE                  BIT(4)
 265
 266/* F17h */
 267
 268/* F0: */
 269#define DF_DHAR                         0x104
 270
 271/* UMC CH register offsets */
 272#define UMCCH_BASE_ADDR                 0x0
 273#define UMCCH_BASE_ADDR_SEC             0x10
 274#define UMCCH_ADDR_MASK                 0x20
 275#define UMCCH_ADDR_MASK_SEC             0x28
 276#define UMCCH_ADDR_MASK_SEC_DDR5        0x30
 277#define UMCCH_ADDR_CFG                  0x30
 278#define UMCCH_ADDR_CFG_DDR5             0x40
 279#define UMCCH_DIMM_CFG                  0x80
 280#define UMCCH_DIMM_CFG_DDR5             0x90
 281#define UMCCH_UMC_CFG                   0x100
 282#define UMCCH_SDP_CTRL                  0x104
 283#define UMCCH_ECC_CTRL                  0x14C
 284#define UMCCH_ECC_BAD_SYMBOL            0xD90
 285#define UMCCH_UMC_CAP                   0xDF0
 286#define UMCCH_UMC_CAP_HI                0xDF4
 287
 288/* UMC CH bitfields */
 289#define UMC_ECC_CHIPKILL_CAP            BIT(31)
 290#define UMC_ECC_ENABLED                 BIT(30)
 291
 292#define UMC_SDP_INIT                    BIT(31)
 293
 294enum amd_families {
 295        K8_CPUS = 0,
 296        F10_CPUS,
 297        F15_CPUS,
 298        F15_M30H_CPUS,
 299        F15_M60H_CPUS,
 300        F16_CPUS,
 301        F16_M30H_CPUS,
 302        F17_CPUS,
 303        F17_M10H_CPUS,
 304        F17_M30H_CPUS,
 305        F17_M60H_CPUS,
 306        F17_M70H_CPUS,
 307        F19_CPUS,
 308        F19_M10H_CPUS,
 309        F19_M50H_CPUS,
 310        NUM_FAMILIES,
 311};
 312
 313/* Error injection control structure */
 314struct error_injection {
 315        u32      section;
 316        u32      word;
 317        u32      bit_map;
 318};
 319
 320/* low and high part of PCI config space regs */
 321struct reg_pair {
 322        u32 lo, hi;
 323};
 324
 325/*
 326 * See F1x[1, 0][7C:40] DRAM Base/Limit Registers
 327 */
 328struct dram_range {
 329        struct reg_pair base;
 330        struct reg_pair lim;
 331};
 332
 333/* A DCT chip selects collection */
 334struct chip_select {
 335        u32 csbases[NUM_CHIPSELECTS];
 336        u32 csbases_sec[NUM_CHIPSELECTS];
 337        u8 b_cnt;
 338
 339        u32 csmasks[NUM_CHIPSELECTS];
 340        u32 csmasks_sec[NUM_CHIPSELECTS];
 341        u8 m_cnt;
 342};
 343
 344struct amd64_umc {
 345        u32 dimm_cfg;           /* DIMM Configuration reg */
 346        u32 umc_cfg;            /* Configuration reg */
 347        u32 sdp_ctrl;           /* SDP Control reg */
 348        u32 ecc_ctrl;           /* DRAM ECC Control reg */
 349        u32 umc_cap_hi;         /* Capabilities High reg */
 350
 351        /* cache the dram_type */
 352        enum mem_type dram_type;
 353};
 354
 355struct amd64_pvt {
 356        struct low_ops *ops;
 357
 358        /* pci_device handles which we utilize */
 359        struct pci_dev *F0, *F1, *F2, *F3, *F6;
 360
 361        u16 mc_node_id;         /* MC index of this MC node */
 362        u8 fam;                 /* CPU family */
 363        u8 model;               /* ... model */
 364        u8 stepping;            /* ... stepping */
 365
 366        int ext_model;          /* extended model value of this node */
 367        int channel_count;
 368
 369        /* Raw registers */
 370        u32 dclr0;              /* DRAM Configuration Low DCT0 reg */
 371        u32 dclr1;              /* DRAM Configuration Low DCT1 reg */
 372        u32 dchr0;              /* DRAM Configuration High DCT0 reg */
 373        u32 dchr1;              /* DRAM Configuration High DCT1 reg */
 374        u32 nbcap;              /* North Bridge Capabilities */
 375        u32 nbcfg;              /* F10 North Bridge Configuration */
 376        u32 ext_nbcfg;          /* Extended F10 North Bridge Configuration */
 377        u32 dhar;               /* DRAM Hoist reg */
 378        u32 dbam0;              /* DRAM Base Address Mapping reg for DCT0 */
 379        u32 dbam1;              /* DRAM Base Address Mapping reg for DCT1 */
 380
 381        /* one for each DCT/UMC */
 382        struct chip_select csels[NUM_CONTROLLERS];
 383
 384        /* DRAM base and limit pairs F1x[78,70,68,60,58,50,48,40] */
 385        struct dram_range ranges[DRAM_RANGES];
 386
 387        u64 top_mem;            /* top of memory below 4GB */
 388        u64 top_mem2;           /* top of memory above 4GB */
 389
 390        u32 dct_sel_lo;         /* DRAM Controller Select Low */
 391        u32 dct_sel_hi;         /* DRAM Controller Select High */
 392        u32 online_spare;       /* On-Line spare Reg */
 393
 394        /* x4, x8, or x16 syndromes in use */
 395        u8 ecc_sym_sz;
 396
 397        /* place to store error injection parameters prior to issue */
 398        struct error_injection injection;
 399
 400        /*
 401         * cache the dram_type
 402         *
 403         * NOTE: Don't use this for Family 17h and later.
 404         *       Use dram_type in struct amd64_umc instead.
 405         */
 406        enum mem_type dram_type;
 407
 408        struct amd64_umc *umc;  /* UMC registers */
 409};
 410
 411enum err_codes {
 412        DECODE_OK       =  0,
 413        ERR_NODE        = -1,
 414        ERR_CSROW       = -2,
 415        ERR_CHANNEL     = -3,
 416        ERR_SYND        = -4,
 417        ERR_NORM_ADDR   = -5,
 418};
 419
 420struct err_info {
 421        int err_code;
 422        struct mem_ctl_info *src_mci;
 423        int csrow;
 424        int channel;
 425        u16 syndrome;
 426        u32 page;
 427        u32 offset;
 428};
 429
 430static inline u32 get_umc_base(u8 channel)
 431{
 432        /* chY: 0xY50000 */
 433        return 0x50000 + (channel << 20);
 434}
 435
 436static inline u64 get_dram_base(struct amd64_pvt *pvt, u8 i)
 437{
 438        u64 addr = ((u64)pvt->ranges[i].base.lo & 0xffff0000) << 8;
 439
 440        if (boot_cpu_data.x86 == 0xf)
 441                return addr;
 442
 443        return (((u64)pvt->ranges[i].base.hi & 0x000000ff) << 40) | addr;
 444}
 445
 446static inline u64 get_dram_limit(struct amd64_pvt *pvt, u8 i)
 447{
 448        u64 lim = (((u64)pvt->ranges[i].lim.lo & 0xffff0000) << 8) | 0x00ffffff;
 449
 450        if (boot_cpu_data.x86 == 0xf)
 451                return lim;
 452
 453        return (((u64)pvt->ranges[i].lim.hi & 0x000000ff) << 40) | lim;
 454}
 455
 456static inline u16 extract_syndrome(u64 status)
 457{
 458        return ((status >> 47) & 0xff) | ((status >> 16) & 0xff00);
 459}
 460
 461static inline u8 dct_sel_interleave_addr(struct amd64_pvt *pvt)
 462{
 463        if (pvt->fam == 0x15 && pvt->model >= 0x30)
 464                return (((pvt->dct_sel_hi >> 9) & 0x1) << 2) |
 465                        ((pvt->dct_sel_lo >> 6) & 0x3);
 466
 467        return  ((pvt)->dct_sel_lo >> 6) & 0x3;
 468}
 469/*
 470 * per-node ECC settings descriptor
 471 */
 472struct ecc_settings {
 473        u32 old_nbctl;
 474        bool nbctl_valid;
 475
 476        struct flags {
 477                unsigned long nb_mce_enable:1;
 478                unsigned long nb_ecc_prev:1;
 479        } flags;
 480};
 481
 482/*
 483 * Each of the PCI Device IDs types have their own set of hardware accessor
 484 * functions and per device encoding/decoding logic.
 485 */
 486struct low_ops {
 487        int (*early_channel_count)      (struct amd64_pvt *pvt);
 488        void (*map_sysaddr_to_csrow)    (struct mem_ctl_info *mci, u64 sys_addr,
 489                                         struct err_info *);
 490        int (*dbam_to_cs)               (struct amd64_pvt *pvt, u8 dct,
 491                                         unsigned cs_mode, int cs_mask_nr);
 492};
 493
 494struct amd64_family_flags {
 495        /*
 496         * Indicates that the system supports the new register offsets, etc.
 497         * first introduced with Family 19h Model 10h.
 498         */
 499        __u64 zn_regs_v2        : 1,
 500
 501              __reserved        : 63;
 502};
 503
 504struct amd64_family_type {
 505        const char *ctl_name;
 506        u16 f0_id, f1_id, f2_id, f6_id;
 507        /* Maximum number of memory controllers per die/node. */
 508        u8 max_mcs;
 509        struct amd64_family_flags flags;
 510        struct low_ops ops;
 511};
 512
 513int __amd64_read_pci_cfg_dword(struct pci_dev *pdev, int offset,
 514                               u32 *val, const char *func);
 515int __amd64_write_pci_cfg_dword(struct pci_dev *pdev, int offset,
 516                                u32 val, const char *func);
 517
 518#define amd64_read_pci_cfg(pdev, offset, val)   \
 519        __amd64_read_pci_cfg_dword(pdev, offset, val, __func__)
 520
 521#define amd64_write_pci_cfg(pdev, offset, val)  \
 522        __amd64_write_pci_cfg_dword(pdev, offset, val, __func__)
 523
 524#define to_mci(k) container_of(k, struct mem_ctl_info, dev)
 525
 526/* Injection helpers */
 527static inline void disable_caches(void *dummy)
 528{
 529        write_cr0(read_cr0() | X86_CR0_CD);
 530        wbinvd();
 531}
 532
 533static inline void enable_caches(void *dummy)
 534{
 535        write_cr0(read_cr0() & ~X86_CR0_CD);
 536}
 537
 538static inline u8 dram_intlv_en(struct amd64_pvt *pvt, unsigned int i)
 539{
 540        if (pvt->fam == 0x15 && pvt->model >= 0x30) {
 541                u32 tmp;
 542                amd64_read_pci_cfg(pvt->F1, DRAM_CONT_LIMIT, &tmp);
 543                return (u8) tmp & 0xF;
 544        }
 545        return (u8) (pvt->ranges[i].base.lo >> 8) & 0x7;
 546}
 547
 548static inline u8 dhar_valid(struct amd64_pvt *pvt)
 549{
 550        if (pvt->fam == 0x15 && pvt->model >= 0x30) {
 551                u32 tmp;
 552                amd64_read_pci_cfg(pvt->F1, DRAM_CONT_BASE, &tmp);
 553                return (tmp >> 1) & BIT(0);
 554        }
 555        return (pvt)->dhar & BIT(0);
 556}
 557
 558static inline u32 dct_sel_baseaddr(struct amd64_pvt *pvt)
 559{
 560        if (pvt->fam == 0x15 && pvt->model >= 0x30) {
 561                u32 tmp;
 562                amd64_read_pci_cfg(pvt->F1, DRAM_CONT_BASE, &tmp);
 563                return (tmp >> 11) & 0x1FFF;
 564        }
 565        return (pvt)->dct_sel_lo & 0xFFFFF800;
 566}
 567