EMIF
The DDR2/3/mDDR memory controller starts servicing new memory accesses after Refresh Release level
is cleared. If any of the commands in the Command FIFO have class of service latency counters that are
expired, the DDR2/3/mDDR memory controller will not wait for Refresh Release level to be cleared but will
only perform one refresh command and exit the refresh state.
7.3.3.5.6 Performance Counter Configuration
shows the possible filter configurations for the two performance counters (REG_CNTR1_CFG
and REG_CNTR2_CFG). These filter configurations can be used in conjunction with an OCP connection
ID and/or an external chip select to obtain performance statistics for a particular OCP master and/or an
external chip select.
Table 7-109. Filter Configurations for Performance Counters
cntrN_cfg
(1)
cntrN_region_en
cntrN_mconnid_en
Description
0x0
0x0
0x0 or 0x1
Count total SDRAM accesses.
0x1
0x0
0x0 or 0x1
Count total SDRAM activations.
0x2
0x0 or 0x1
0x0 or 0x1
Count total reads.
0x3
0x0 or 0x1
0x0 or 0x1
Count total writes.
Count number of DDR clock cycles OCP
0x4
0x0
0x0
Command FIFO is full.
Count number of DDR clock cycles OCP
0x5
0x0
0x0
Write Data FIFO is full.
Count number of DDR clock cycles OCP
0x6
0x0
0x0
Read Data FIFO is full.
Count number of DDR clock cycles OCP
0x7
0x0
0x0
Return Command FIFO is full.
0x8
0x0 or 0x1
0x0 or 0x1
Count number of priority elevations.
Count number of DDR clock cycles that a
0x9
0x0
0x0
command was pending.
Count number of DDR clock cycles for
0xA
0x0
0x0
which the memory data bus was
transferring data.
0xB - 0xF
0x0
0x0
Reserved for future use.
(1)
When MReqDebug is set to a 1 for a particular OCP command, the performance counters will not be incremented for that
particular command if the cntrN_cfg values are equal to 0x0, 0x1, 0x2, 0x3, or 0xA.
7.3.3.6
DDR3 Read-Write Leveling
The DDR2/3/mDDR memory controller supports read-write leveling in conjunction with the DDR PHY. The
DDR2/3/mDDR memory controller supports two types of write/read leveling:
1. Full leveling
2. Incremental leveling
NOTE:
Please refer the device specific data sheet to know the type of leveling supported.
Each leveling type has three parts:
1. Write leveling
2. Read DQS gate training
3. Read data eye training
Read and write leveling is only supported to DDR3 memory.
417
SPRUH73H – October 2011 – Revised April 2013
Memory Subsystem
Copyright © 2011–2013, Texas Instruments Incorporated