ARM Cortex-X4 explained
The ARM Cortex-X4 is a high-performance CPU core from Arm, released in 2023 as part of Arm's "total compute solution."[1] It serves as the successor of ARM Cortex-X3. X-series CPU cores generally focus on high performance, and can be grouped with other ARM cores, such as ARM Cortex-A720 or/and ARM Cortex-A520 in a System-on-Chip (SoC).[2] [3] [4] [5]
| ARM Cortex-X4 |
| Produced-Start: | 2023 |
| Designfirm: | ARM Ltd. |
| Address-Width: | 40-bit |
| L1cache: | per core |
| L2cache: | per core |
| Arch: | ARMv9.2-A |
| Microarch: | ARM Cortex-X4 |
| Numcores: | 1–10 per cluster |
| Pcode1: | "Hunter ELP" |
| Variant: | ARM Cortex-A720 |
| Predecessor: | ARM Cortex-X3 |
| Successor: | ARM Cortex-X925 |
The processor implements the following changes:
- micro-op (MOP) cache removed (previously 1.5k entries)
- Decode width: 10
- Rename / Dispatch width: 10 (increased from 8)
- Reorder buffer (ROB): 384 entries (increased from 320)
- Execution ports: 21 (increased from 15)
- Pipeline length: 10 (increased from 9)
- Up to 2 MiB of private L2 cache (increased from 1 MiB)
- DSU-120
- Up to 14 cores (up from 12 cores)
- Up to 32 MiB of shared L3 cache (increased from 16 MiB)
- ARMv9.2
Performance claims:
- 15% peak performance improvement over the Cortex-X3 in smartphones (3.4GHz, 2MB L2, 8MB L3).
- 13% IPC uplift over the Cortex-X3, when based on the same process, clock speed, and L3 cache (but 2 MiB L2 vs 1 MiB L2) setup (also known as ISO-process).
Architecture comparison
| uArch | Cortex-A78 | Cortex-X1 | Cortex-X2 | Cortex-X3 | Cortex-X4 | Cortex-X925 |
|---|
| Peak clock speed | ~3.0 GHz | ~3.25 GHz | ~3.4 GHz | ~3.8 Ghz |
|---|
| Decode Width | 4 | 5 | 6 | 10[6] | 10 |
|---|
| Dispatch | 6/cycle | 8/cycle | 10/cycle | 10/cycle |
|---|
| Max In-flight | 2x160 | 2x224 | 2x288 | 2x320 | 2x384 | 2x768 |
|---|
| L0 (Mops entries) | 1536[7] | 3,072 | 1536 | None | |
|---|
| L1-I + L1-D | 32+32 KiB[8] | 64+64 KiB | 64+64 KiB |
|---|
| L2 | 128–512 KiB | 256KiB – 1 MiB | 0.5 – 2 MiB | 0.5 – 3MiB |
|---|
| L3 | 0–8 MiB | 0–16 MiB | 0–32 MiB | 0–32 MiB |
|---|
| Architecture | ARMv8.2 | ARMv9 | ARMv9.2 | ARMv9.2 | |
|---|
Usage
See also
- ARM Cortex-A720, related efficient sustained performance microarchitecture
- ARM Cortex-A520, related high efficient microarchitecture
- Comparison of ARMv8-A cores
Notes and References
- Web site: Dahad . Nitin . 2023-06-02 . Arm Total Compute Solution 2023 targets premium smartphones . 2024-01-17 . Embedded.com . en-US.
- Web site: 2023-05-29 . Arm Cortex-X4 advances frontiers of CPU performance - Announcements - Arm Community blogs - Arm Community . 2023-09-16 . community.arm.com . en.
- Web site: 2023-05-28 . Arm Introduces The Cortex-X4, Its Newest Flagship Performance Core . 2023-05-30 . WikiChip Fuse . en-US.
- Web site: Bonshor . Gavin . Arm Unveils 2023 Mobile CPU Core Designs: Cortex-X4, A720, and A520 - the Armv9.2 Family . 2023-05-30 . www.anandtech.com.
- Web site: 2023-05-29 . TCS23: The complete platform for consumer computing - Announcements - Arm Community blogs - Arm Community . 2023-09-16 . community.arm.com . en.
- Web site: 2023-05-29 . Arm Cortex-X4, A720, and A520: 2024 smartphone CPUs deep dive . 2023-06-01 . Android Authority . en.
- Web site: Frumusanu . Andrei . Arm's New Cortex-A78 and Cortex-X1 Microarchitectures: An Efficiency and Performance Divergence . 2023-06-01 . www.anandtech.com.
- Web site: Schor . David . 2020-05-26 . Arm Cortex-X1: The First From The Cortex-X Custom Program . 2023-05-30 . WikiChip Fuse . en-US.
- Web site: 2023-05-29 . MediaTek says its Snapdragon 8 Gen 3 rival will be a beast (Updated) . 2023-09-16 . Android Authority . en.
- Web site: 2023-05-29 . Qualcomm Snapdragon Tech Summit Live Blog: Compute Spotlight . 2023-09-16 . Android Authority . en.
- Web site: 2024-06-01 . Latest Pixel 9 leak gives us a look at the Tensor G4 specs and benchmarks . 2024-06-01 . Android Authority . en.
