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The Qualcomm Dragonwing IQ-8275 features an advanced memory subsystem designed for high-performance computing applications.

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Specifications

SpecificationDetails
Memory TypeLPDDR5X / LPDDR5 SDRAM
ConfigurationSix-channel non-PoP
Maximum Density36 GB
Clock SpeedUp to 3200 MHz
Data Width6 × 16-bit (96-bit total)
StandardsJEDEC LPDDR5X/LPDDR5 compliant

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Architecture

The IQ-8275 memory controller supports high-bandwidth, low-latency operations across six independent 16-bit channels with dynamic frequency scaling for power optimization.

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Supported DRAM Components

All DRAM components must be selected from the Qualcomm Preferred Vendor List (PVL).
1

Access the PVL database

Navigate to the Qualcomm PVL and sign in with your Qualcomm account.
2

Download the PVL file

Download the QRD Hardware - Preferred Vendor List (PVL) Excel file.
3

Filter for IQ-8275 memory

Filter by Type: Memory and Chipset: IQ-8275.

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Initialization

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Setup and Configuration

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Prerequisites

  • IQ-8275 development board with PVL-compliant LPDDR5X or LPDDR5 DRAM
  • Canonical Ubuntu software package
  • XBL bootloader with DSF (DDR System Firmware)
  • UART debug cable and SSH access

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Initial Setup

1

Verify DRAM component

Confirm your DRAM part number is listed in the Qualcomm PVL for IQ-8275.
2

Flash the software package

fastboot flash xbl xbl.elf
fastboot flashall
3

Boot and verify detection

Connect UART console (115200 baud, 8N1) and watch for initialization messages:
  • sbl1_ddr_init, Start
  • LP5 DDR detected
  • Manufacturer ID = XXXX, Device Type = XXXX
  • Max enabled DDR Freq = 3200 MHz

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Frequency Scaling

cat /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/cur_freq
cat /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/available_frequencies
echo <frequency> > /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/userspace/set_freq

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Debugging

dmesg | grep -i ddr
cat /proc/meminfo
cat /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/cur_freq

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Troubleshooting

Symptoms: No DRAM detection in UART logs; boot hangs at XBL stage.
  • Verify DRAM modules are properly seated
  • Measure VDD and VDDQ voltages — ensure they meet JEDEC specifications
  • Contact Qualcomm support if hardware is verified
Symptoms: Boot hangs after DRAM detection; training/calibration failures.
  • Check temperature and voltage stability
  • Verify signal quality on all channels
  • Try booting at a lower frequency
cat /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/cur_freq
cat /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/governor
cat /sys/class/thermal/thermal_zone*/temp
Set performance governor:
echo performance > /sys/class/devfreq/soc:qcom,cpu-llcc-ddr-bw/governor

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Resources

ResourceURL
JEDEC LPDDR Standardshttps://www.jedec.org/category/technology-focus-area/mobile-memory-lpddr-wide-io-memory-mcp
Qualcomm PVLhttps://www.qualcomm.com/preferred-vendor-list
Qualcomm Software Centerhttps://softwarecenter.qualcomm.com/#/