1# Copyright (c) 2012-2014 ARM Limited 2# All rights reserved. 3# 4# The license below extends only to copyright in the software and shall 5# not be construed as granting a license to any other intellectual 6# property including but not limited to intellectual property relating 7# to a hardware implementation of the functionality of the software 8# licensed hereunder. You may use the software subject to the license --- 105 unchanged lines hidden (view full) --- 114 banks_per_rank = Param.Unsigned("Number of banks per rank") 115 # only used for the address mapping as the controller by 116 # construction is a single channel and multiple controllers have 117 # to be instantiated for a multi-channel configuration 118 channels = Param.Unsigned(1, "Number of channels") 119 120 # timing behaviour and constraints - all in nanoseconds 121 |
122 # the base clock period of the DRAM 123 tCK = Param.Latency("Clock period") 124 |
125 # the amount of time in nanoseconds from issuing an activate command 126 # to the data being available in the row buffer for a read/write 127 tRCD = Param.Latency("RAS to CAS delay") 128 129 # the time from issuing a read/write command to seeing the actual data 130 tCL = Param.Latency("CAS latency") 131 132 # minimum time between a precharge and subsequent activate --- 60 unchanged lines hidden (view full) --- 193 devices_per_rank = 8 194 195 # Use two ranks 196 ranks_per_channel = 2 197 198 # DDR3 has 8 banks in all configurations 199 banks_per_rank = 8 200 |
201 # 800 MHz 202 tCK = '1.25ns' 203 |
204 # DDR3-1600 11-11-11-28 205 tRCD = '13.75ns' 206 tCL = '13.75ns' 207 tRP = '13.75ns' 208 tRAS = '35ns' 209 tWR = '15ns' 210 tRTP = '7.5ns' 211 --- 45 unchanged lines hidden (view full) --- 257 devices_per_rank = 8 258 259 # Use two ranks 260 ranks_per_channel = 2 261 262 # DDR3 has 8 banks in all configurations 263 banks_per_rank = 8 264 |
265 # 666 MHs 266 tCK = '1.5ns' 267 |
268 tRCD = '15ns' 269 tCL = '15ns' 270 tRP = '15ns' 271 tRAS = '36ns' 272 tWR = '15ns' 273 tRTP = '7.5ns' 274 275 # 8 beats across an x64 interface translates to 4 clocks @ 666.66 MHz. --- 35 unchanged lines hidden (view full) --- 311 devices_per_rank = 1 312 313 # Use a single rank 314 ranks_per_channel = 1 315 316 # LPDDR2-S4 has 8 banks in all configurations 317 banks_per_rank = 8 318 |
319 # 533 MHz 320 tCK = '1.876ns' 321 |
322 # Fixed at 15 ns 323 tRCD = '15ns' 324 325 # 8 CK read latency, 4 CK write latency @ 533 MHz, 1.876 ns cycle time 326 tCL = '15ns' 327 328 # Pre-charge one bank 15 ns (all banks 18 ns) 329 tRP = '15ns' --- 44 unchanged lines hidden (view full) --- 374 devices_per_rank = 1 375 376 # Use one rank for a one-high die stack 377 ranks_per_channel = 1 378 379 # WideIO has 4 banks in all configurations 380 banks_per_rank = 4 381 |
382 # 200 MHz 383 tCK = '5ns' 384 |
385 # WIO-200 386 tRCD = '18ns' 387 tCL = '18ns' 388 tRP = '18ns' 389 tRAS = '42ns' 390 tWR = '15ns' 391 # Read to precharge is same as the burst 392 tRTP = '20ns' --- 38 unchanged lines hidden (view full) --- 431 devices_per_rank = 1 432 433 # Use a single rank 434 ranks_per_channel = 1 435 436 # LPDDR3 has 8 banks in all configurations 437 banks_per_rank = 8 438 |
439 # 800 MHz 440 tCK = '1.25ns' 441 |
442 # Fixed at 15 ns 443 tRCD = '15ns' 444 445 # 12 CK read latency, 6 CK write latency @ 800 MHz, 1.25 ns cycle time 446 tCL = '15ns' 447 448 tRAS = '42ns' 449 tWR = '15ns' --- 29 unchanged lines hidden --- |