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