jedec_ddr.h

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/*
 * Definitions for DDR memories based on JEDEC specs
 *
 * Copyright (C) 2012 Texas Instruments, Inc.
 *
 * Aneesh V <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef __LINUX_JEDEC_DDR_H
#define __LINUX_JEDEC_DDR_H

#include <linux/types.h>

/* DDR Densities */
#define DDR_DENSITY_64Mb    1
#define DDR_DENSITY_128Mb   2
#define DDR_DENSITY_256Mb   3
#define DDR_DENSITY_512Mb   4
#define DDR_DENSITY_1Gb     5
#define DDR_DENSITY_2Gb     6
#define DDR_DENSITY_4Gb     7
#define DDR_DENSITY_8Gb     8
#define DDR_DENSITY_16Gb    9
#define DDR_DENSITY_32Gb    10

/* DDR type */
#define DDR_TYPE_DDR2       1
#define DDR_TYPE_DDR3       2
#define DDR_TYPE_LPDDR2_S4  3
#define DDR_TYPE_LPDDR2_S2  4
#define DDR_TYPE_LPDDR2_NVM 5

/* DDR IO width */
#define DDR_IO_WIDTH_4      1
#define DDR_IO_WIDTH_8      2
#define DDR_IO_WIDTH_16     3
#define DDR_IO_WIDTH_32     4

/* Number of Row bits */
#define R9          9
#define R10         10
#define R11         11
#define R12         12
#define R13         13
#define R14         14
#define R15         15
#define R16         16

/* Number of Column bits */
#define C7          7
#define C8          8
#define C9          9
#define C10         10
#define C11         11
#define C12         12

/* Number of Banks */
#define B1          0
#define B2          1
#define B4          2
#define B8          3

/* Refresh rate in nano-seconds */
#define T_REFI_15_6     15600
#define T_REFI_7_8      7800
#define T_REFI_3_9      3900

/* tRFC values */
#define T_RFC_90        90000
#define T_RFC_110       110000
#define T_RFC_130       130000
#define T_RFC_160       160000
#define T_RFC_210       210000
#define T_RFC_300       300000
#define T_RFC_350       350000

/* Mode register numbers */
#define DDR_MR0         0
#define DDR_MR1         1
#define DDR_MR2         2
#define DDR_MR3         3
#define DDR_MR4         4
#define DDR_MR5         5
#define DDR_MR6         6
#define DDR_MR7         7
#define DDR_MR8         8
#define DDR_MR9         9
#define DDR_MR10        10
#define DDR_MR11        11
#define DDR_MR16        16
#define DDR_MR17        17
#define DDR_MR18        18

/*
 * LPDDR2 related defines
 */

/* MR4 register fields */
#define MR4_SDRAM_REF_RATE_SHIFT            0
#define MR4_SDRAM_REF_RATE_MASK             7
#define MR4_TUF_SHIFT                   7
#define MR4_TUF_MASK                    (1 << 7)

/* MR4 SDRAM Refresh Rate field values */
#define SDRAM_TEMP_NOMINAL              0x3
#define SDRAM_TEMP_RESERVED_4               0x4
#define SDRAM_TEMP_HIGH_DERATE_REFRESH          0x5
#define SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS  0x6
#define SDRAM_TEMP_VERY_HIGH_SHUTDOWN           0x7

#define NUM_DDR_ADDR_TABLE_ENTRIES          11
#define NUM_DDR_TIMING_TABLE_ENTRIES            4

/* Structure for DDR addressing info from the JEDEC spec */
struct lpddr2_addressing {
    u32 num_banks;
    u32 tREFI_ns;
    u32 tRFCab_ps;
};

/*
 * Structure for timings from the LPDDR2 datasheet
 * All parameters are in pico seconds(ps) unless explicitly indicated
 * with a suffix like tRAS_max_ns below
 */
struct lpddr2_timings {
    u32 max_freq;
    u32 min_freq;
    u32 tRPab;
    u32 tRCD;
    u32 tWR;
    u32 tRAS_min;
    u32 tRRD;
    u32 tWTR;
    u32 tXP;
    u32 tRTP;
    u32 tCKESR;
    u32 tDQSCK_max;
    u32 tDQSCK_max_derated;
    u32 tFAW;
    u32 tZQCS;
    u32 tZQCL;
    u32 tZQinit;
    u32 tRAS_max_ns;
};

/*
 * Min value for some parameters in terms of number of tCK cycles(nCK)
 * Please set to zero parameters that are not valid for a given memory
 * type
 */
struct lpddr2_min_tck {
    u32 tRPab;
    u32 tRCD;
    u32 tWR;
    u32 tRASmin;
    u32 tRRD;
    u32 tWTR;
    u32 tXP;
    u32 tRTP;
    u32 tCKE;
    u32 tCKESR;
    u32 tFAW;
};

extern const struct lpddr2_addressing
    lpddr2_jedec_addressing_table[NUM_DDR_ADDR_TABLE_ENTRIES];
extern const struct lpddr2_timings
    lpddr2_jedec_timings[NUM_DDR_TIMING_TABLE_ENTRIES];
extern const struct lpddr2_min_tck lpddr2_jedec_min_tck;

#endif /* __LINUX_JEDEC_DDR_H */