Additional details of each parameter
of this section can be found in the list below:
- Board Project Name:
- Description: This
parameter is not used in version 0.10.0 or earlier of the Jacinto 7
DDRSS Register Configuration Tool.
- Valid Values: NA
- Recommended Value:
NA
- TI System-on-Chip (SoC) Part
Number:
- Description: Defines the
TI processor part number used in the system.
- Valid Values: Defined by
a drop-down menu list, matching the supported TI processors by the
tool.
- Recommended Value: This
parameter must be selected to match the TI processor part number being
used in the system. The output of the tool could vary depending on
the selected SoC, so it is imperative that the correct part number
is used!
- DDR Controllers Utilized in
System:
- Description: Defines
which DDRSS instances of the TI SoC are connected to external memory and
should be configured by software.
- Valid Values: Defined by
a drop-down menu list, matching the supported combination of DDR
sub-systems that can be enabled for the selected TI SoC.
- Recommended Value:
N/A
Note: The
drop-down list for this parameter is dependent on the user input of
the 'TI SoC Part Number.
- DDR Memory Type:
- Description: Defines the
type of DDR memory used in the system.
- Valid Values: Defined by
a drop-down menu list, matching the supported DDR memory types by the
tool.
- Recommended Value: Only
one option, "LPDDR4", is supported by the tool.
- DDR Memory Boot Frequency
(Frequency Set 0):
- Description: Defines the
DDR memory clock frequency during the DRAM initialization, or
tCKb as defined in the specific DDR component data
sheet.
- Valid Values: For
supported tCKb frequencies, see the specific DDR component
data sheet.
- Recommended Value: It is
recommended to match the TI default value.
Note: The usage of this
parameter has different impact depending on the versions of SDK and Jacinto
7 DDRSS Register Configuration Tool being used. Prior to SDK8.0 and Jacinto
7 DDRSS Register Configuration Tool version 0.6.0, this parameter impacted
the *_F0 timing parameters but did NOT control the actual LPDDR4 boot
frequency. Rather, the LPDDR4 boot frequency is 2x the PLL12 bypass clock,
or 2x the oscillator frequency, in SDKs released prior to SDK8.0. Starting
with SDK8.0 and Jacinto 7 DDRSS Register Configuration Tool version 0.6.0,
this parameter impacts both the *_F0 timing parameters and the LPDDR4 boot
frequency.
- DDR Memory Frequency
(Frequency Set 1):
- Description: Defines the
target DDR memory clock frequency during normal operation when the
LPDDR4 is configured for frequency set point 0.
- Valid Values: Not
configurable. As the tool does not support different frequency set
points, this value must match input parameter DDR Memory Frequency
(Frequency Set 2), and automatically updates in the tool to reflect this
requirement.
- Recommended Value:
NA
- DDR Memory Frequency
(Frequency Set 2):
- Description: Defines the
target DDR memory clock frequency during normal operation when the
LPDDR4 is configured for frequency set point 1.
- Valid Values: For
supported frequencies, see the TI device-specific data sheet, as well as
the specific DDR component data sheet. Note that this parameter should
be set to the clock rate, and not the data rate.
- Recommended Value: Value
must be within the min/max supported limits of both the TI processor
DDRSS and DDR.
- DDR Data Bus Width:
- Description: Defines the
bus width utilized by the DDR interface.
- Valid Values: Defined by
a drop-down menu list, matching the supported bus widths by the
tool.
- Recommended Value: Value
should be set to match the number of physical data (DQ) IO pins which
are connected between the processor's DDRSS and the LPDDR4 memory on the
printed circuit board (PCB).
- DDR Density:
- Description: Defines the
density of a single channel from a single rank of the LPDDR4 memory. As
an example, if the LPDDR4 memory has total density of 32Gb across 2
channels and 2 ranks, then this parameter should be set to 8Gb. Or if
the LPDDR4 memory has total density of 8Gb across 2 channels and 1 rank,
then this parameter should be set to 4Gb.
- Valid Values: Defined by
a drop-down menu list, matching the supported densities by the
tool.
- Recommended Value: Value
should be set to match the density, as described by this parameter's
description, of the LPDDR4 used in the system.
- Chip Selects / Ranks:
- Description: Defines the
number of ranks, or chip selects, utilized for the DDR interface.
Although the LPDDR4 interface has a unique chip select for each channel,
usage of CS0_A and CS0_B should be considered 1 rank. Usage of CS0_A and
CS1_A should be considered 2 ranks. In other words, this parameter
defines the number of chip selects per channel.
- Valid Values: Defined by
a drop-down menu list, matching the supported ranks by the tool.
- Recommended Value: Value
should be set to match the number of ranks, as described by this
parameter's description, utilized by the DDR interface.
- Enable DRAM Temperature
Polling:
- Description: This
parameter enables or disables LPDDR4 temperature polling during normal
operation. When enabled, the controller will periodically send a Mode
Register Read request to the LPDDR4 to read MR4. The purpose of enabling
DRAM temperature polling would be to dynamically change the refresh rate
depending on the temperature of the LPDDR4.
- Valid Values: Defined by
a drop-down menu list.
- Recommended Value: Usage
of this feature will be system dependent, and could be impacted by the
temperatures the LPDDR4 may be subject to in the end application, as
well as by throughput requirements of the system.
Note: Enabling this
parameter ONLY allows the controller to periodically read MR4 of the LPDDR4.
It does NOT change the refresh rate. A software interrupt service routine is
required to service the changes in temperature.
If the refresh rate is
not changed dynamically, you should ensure that the fastest refresh rate
required by the LPDDR4 is programmed in the corresponding timing
parameters in the "DRAMTiming" worksheet.
Temperature de-rating
must be accounted for in the "DRAMTiming" worksheet, regardless of the
configuration of this parameter.
- System Temperature
Gradient:
- Description: Defines the
maximum temperature gradient the system, specifically the DDR, will be
subject to in the target end application. In other words, this parameter
defines how quickly the temperature of the DDR will change.
- Valid Values: Any decimal
value greater than zero.
- Recommended Value: NA,
this parameter is system dependent and must be defined by the end
user.
Note: This parameter is not
used when DRAM temperature polling is disabled.
- Multi DDRSS Interleave Hybrid
Config
- Description: Determines
how the DDR subsystems are interleaved when multiple DDR subsystems are
in use.
- Valid Values: Defined by
a drop-down menu list, matching the supported configurations for the
selected TI SOC and number of DDR subsystems in use.
- Multi DDRSS Interleave Memory
Size
- Description: Determines
the size of the interleaved memory region.
- Valid Values: Defined by
a drop-down menu list, matching the supported configurations based on
the number of DDR subsystems in use and the corresponding LP4 memories
connected.
- Multi DDRSS Interleave
Granularity
- Description: Determines
the granularity at which the DDR subsystems are interleaved within the
interleaved memory region.
- Valid Values: Defined by
a drop-down menu list, matching the supported configurations based on
the number of DDR subsystems in use and the interleaved memory region
size.