1 /* 2 * EMIF programming 3 * 4 * (C) Copyright 2010 5 * Texas Instruments, <www.ti.com> 6 * 7 * Aneesh V <aneesh@ti.com> for OMAP4 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 12 #include <common.h> 13 #include <asm/emif.h> 14 #include <asm/arch/sys_proto.h> 15 #include <asm/utils.h> 16 17 #ifndef CONFIG_SYS_EMIF_PRECALCULATED_TIMING_REGS 18 #define print_timing_reg(reg) debug(#reg" - 0x%08x\n", (reg)) 19 static u32 *const T_num = (u32 *)OMAP_SRAM_SCRATCH_EMIF_T_NUM; 20 static u32 *const T_den = (u32 *)OMAP_SRAM_SCRATCH_EMIF_T_DEN; 21 #endif 22 23 #ifdef CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS 24 /* Base AC Timing values specified by JESD209-2 for 532MHz operation */ 25 static const struct lpddr2_ac_timings timings_jedec_532_mhz = { 26 .max_freq = 532000000, 27 .RL = 8, 28 .tRPab = 21, 29 .tRCD = 18, 30 .tWR = 15, 31 .tRASmin = 42, 32 .tRRD = 10, 33 .tWTRx2 = 15, 34 .tXSR = 140, 35 .tXPx2 = 15, 36 .tRFCab = 130, 37 .tRTPx2 = 15, 38 .tCKE = 3, 39 .tCKESR = 15, 40 .tZQCS = 90, 41 .tZQCL = 360, 42 .tZQINIT = 1000, 43 .tDQSCKMAXx2 = 11, 44 .tRASmax = 70, 45 .tFAW = 50 46 }; 47 48 /* 49 * Min tCK values specified by JESD209-2 50 * Min tCK specifies the minimum duration of some AC timing parameters in terms 51 * of the number of cycles. If the calculated number of cycles based on the 52 * absolute time value is less than the min tCK value, min tCK value should 53 * be used instead. This typically happens at low frequencies. 54 */ 55 static const struct lpddr2_min_tck min_tck_jedec = { 56 .tRL = 3, 57 .tRP_AB = 3, 58 .tRCD = 3, 59 .tWR = 3, 60 .tRAS_MIN = 3, 61 .tRRD = 2, 62 .tWTR = 2, 63 .tXP = 2, 64 .tRTP = 2, 65 .tCKE = 3, 66 .tCKESR = 3, 67 .tFAW = 8 68 }; 69 70 static const struct lpddr2_ac_timings const* 71 jedec_ac_timings[MAX_NUM_SPEEDBINS] = { 72 &timings_jedec_532_mhz 73 }; 74 75 static const struct lpddr2_device_timings jedec_default_timings = { 76 .ac_timings = jedec_ac_timings, 77 .min_tck = &min_tck_jedec 78 }; 79 80 void emif_get_device_timings(u32 emif_nr, 81 const struct lpddr2_device_timings **cs0_device_timings, 82 const struct lpddr2_device_timings **cs1_device_timings) 83 { 84 /* Assume Identical devices on EMIF1 & EMIF2 */ 85 *cs0_device_timings = &jedec_default_timings; 86 *cs1_device_timings = NULL; 87 } 88 #endif /* CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS */ 89