From 43abaf518f00c38415e08b7c96941d192316208f Mon Sep 17 00:00:00 2001 From: Neha Agarwal Date: Sun, 23 Mar 2014 11:11:56 -0400 Subject: [PATCH] mem: DDR3 config for comparing with DRAMSim2 This patch adds a new DDR3 configuration to match with the parameters that are specified in one of the DDR3 configs used in DRAMSim2. --- src/mem/SimpleDRAM.py | 52 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/src/mem/SimpleDRAM.py b/src/mem/SimpleDRAM.py index 0404af99b..7b8e506ac 100644 --- a/src/mem/SimpleDRAM.py +++ b/src/mem/SimpleDRAM.py @@ -205,6 +205,58 @@ class DDR3_1600_x64(SimpleDRAM): activation_limit = 4 +# A single DDR3 x64 interface (one command and address bus), with +# default timings based on DDR3-1333 4 Gbit parts in an 8x8 +# configuration, which would amount to 4 GByte of memory. This +# configuration is primarily for comparing with DRAMSim2, and all the +# parameters except ranks_per_channel are based on the DRAMSim2 config +# file DDR3_micron_32M_8B_x8_sg15.ini. Note that ranks_per_channel has +# to be manually set, depending on size of the memory to be +# simulated. By default DRAMSim2 has 2048MB of memory with a single +# rank. Therefore for 4 GByte memory, set ranks_per_channel = 2 +class DDR3_1333_x64_DRAMSim2(SimpleDRAM): + # 8x8 configuration, 8 devices each with an 8-bit interface + device_bus_width = 8 + + # DDR3 is a BL8 device + burst_length = 8 + + # Each device has a page (row buffer) size of 1KB + # (this depends on the memory density) + device_rowbuffer_size = '1kB' + + # 8x8 configuration, so 8 devices + devices_per_rank = 8 + + # Use two ranks + ranks_per_channel = 2 + + # DDR3 has 8 banks in all configurations + banks_per_rank = 8 + + tRCD = '15ns' + tCL = '15ns' + tRP = '15ns' + tRAS = '36ns' + + # 8 beats across an x64 interface translates to 4 clocks @ 666.66 MHz. + # Note this is a BL8 DDR device. + tBURST = '6ns' + + tRFC = '160ns' + + # DDR3, <=85C, half for >85C + tREFI = '7.8us' + + # Greater of 4 CK or 7.5 ns, 4 CK @ 666.66 MHz = 6 ns + tWTR = '7.5ns' + + tRRD = '6.0ns' + + tXAW = '30ns' + activation_limit = 4 + + # A single LPDDR2-S4 x32 interface (one command/address bus), with # default timings based on a LPDDR2-1066 4 Gbit part in a 1x32 # configuration. -- 2.30.2