CTTE Demonstrator - a recorded bring-up session, replayed live

The CTTE bring-up dashboard replaying a recorded two-hart RISC-V^® Linux^® boot in your browser: real console, real trace bytes, no board, no server.

What you are looking at

The panel above is not a mock-up. It is the bring-up dashboard we use at the board, embedded unchanged, fed by a recording of one demo run per scenario. Press Run on the left core card and the recorded Linux^® boot plays back in real time: the console follows the kernel’s own timestamps, the byte counters and the bits-per-instruction chart follow the recorded time series, and the register panel answers from a memory image of the real register map.

From the lab to this page: the bring-up chain feeds one recorded run, and this page replays it in the browser. Click the OpenSBI console window to read the full recorded boot log.

Recorded console - Rocket64t2 SMP Linux boot

OpenSBI v1.6
   ____                    _____ ____ _____
  / __ \                  / ____|  _ \_   _|
 | |  | |_ __   ___ _ __ | (___ | |_) || |
 | |  | | '_ \ / _ \ '_ \ \___ \|  _ < | |
 | |__| | |_) |  __/ | | |____) | |_) || |_
  \____/| .__/ \___|_| |_|_____/|____/_____|
        | |
        |_|

Platform Name               : Accemic Rocket64t2 RV64 CTTE Demonstrator, 2 Harts (KV260 PL)
Platform Features           : medeleg
Platform HART Count         : 2
Platform IPI Device         : aclint-mswi
Platform Timer Device       : aclint-mtimer @ 750000Hz
Platform Console Device     : uart8250
Platform HSM Device         : ---
Platform PMU Device         : ---
Platform Reboot Device      : ---
Platform Shutdown Device    : ---
Platform Suspend Device     : ---
Platform CPPC Device        : ---
Firmware Base               : 0x80000000
Firmware Size               : 337 KB
Firmware RW Offset          : 0x40000
Firmware RW Size            : 81 KB
Firmware Heap Offset        : 0x4a000
Firmware Heap Size          : 41 KB (total), 2 KB (reserved), 13 KB (used), 25 KB (free)
Firmware Scratch Size       : 4096 B (total), 440 B (used), 3656 B (free)
Runtime SBI Version         : 2.0
Standard SBI Extensions     : time,rfnc,ipi,base,hsm,pmu,dbcn,legacy
Experimental SBI Extensions : fwft,dbtr,sse

Domain0 Name                : root
Domain0 Boot HART           : 0
Domain0 HARTs               : 0*,1*
Domain0 Region00            : 0x0000000060010000-0x0000000060010fff M: (I,R,W) S/U: (R,W)
Domain0 Region01            : 0x0000000002000000-0x000000000200ffff M: (I,R,W) S/U: ()
Domain0 Region02            : 0x0000000080040000-0x000000008005ffff M: (R,W) S/U: ()
Domain0 Region03            : 0x0000000080000000-0x000000008003ffff M: (R,X) S/U: ()
Domain0 Region04            : 0x000000000c000000-0x000000000fffffff M: (I,R,W) S/U: (R,W)
Domain0 Region05            : 0x0000000000000000-0xffffffffffffffff M: () S/U: (R,W,X)
Domain0 Next Address        : 0x0000000080200000
Domain0 Next Arg1           : 0x0000000082200000
Domain0 Next Mode           : S-mode
Domain0 SysReset            : yes
Domain0 SysSuspend          : yes

Boot HART ID                : 0
Boot HART Domain            : root
Boot HART Priv Version      : v1.12
Boot HART Base ISA          : rv64imacx
Boot HART ISA Extensions    : sdtrig
Boot HART PMP Count         : 8
Boot HART PMP Granularity   : 2 bits
Boot HART PMP Address Bits  : 32
Boot HART MHPM Info         : 0 (0x00000000)
Boot HART Debug Triggers    : 8 triggers
Boot HART MIDELEG           : 0x0000000000000222
Boot HART MEDELEG           : 0x000000000000b109
[    0.000000] Linux version 6.12.19 (aweiss@panama) (riscv64-buildroot-linux-gnu-gcc.br_real (Buildroot 2025.02) 13.3.0, GNU ld (GNU Binutils) 2.43.1) #6 SMP Sun Aug  9 16:15:17 CEST 2026
[    0.000000] Machine model: Accemic Rocket64t2 RV64 CTTE Demonstrator, 2 Harts (KV260 PL)
[    0.000000] SBI specification v2.0 detected
[    0.000000] SBI implementation ID=0x1 Version=0x10006
[    0.000000] SBI TIME extension detected
[    0.000000] SBI IPI extension detected
[    0.000000] SBI RFENCE extension detected
[    0.000000] SBI DBCN extension detected
[    0.000000] earlycon: uart8250 at MMIO32 0x0000000060010000 (options '')
[    0.000000] printk: legacy bootconsole [uart8250] enabled
[    0.000000] printk: debug: skip boot console de-registration..
[    0.000000] Disabled 4-level and 5-level paging
[    0.000000] OF: reserved mem: 0x0000000080000000..0x000000008003ffff (256 KiB) nomap non-reusable mmode_resv1@80000000
[    0.000000] OF: reserved mem: 0x0000000080040000..0x000000008005ffff (128 KiB) nomap non-reusable mmode_resv0@80040000
[    0.000000] Zone ranges:
[    0.000000]   DMA32    [mem 0x0000000080000000-0x000000008bffffff]
[    0.000000]   Normal   empty
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000080000000-0x000000008005ffff]
[    0.000000]   node   0: [mem 0x0000000080060000-0x000000008bffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000008bffffff]
[    0.000000] On node 0, zone DMA32: 16384 pages in unavailable ranges
[    0.000000] SBI HSM extension detected
[    0.000000] riscv: base ISA extensions acim
[    0.000000] riscv: ELF capabilities acim
[    0.000000] percpu: Embedded 21 pages/cpu s48872 r8192 d28952 u86016
[    0.000000] Kernel command line: earlycon=uart8250,mmio32,0x60010000 keep_bootcon console=ttyS0 no4lvl rdinit=/sbin/init
[    0.000000] Dentry cache hash table entries: 32768 (order: 6, 262144 bytes, linear)
[    0.000000] Inode-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 49152
[    0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
[    0.000000] Virtual kernel memory layout:
[    0.000000]       fixmap : 0xffffffc4fea00000 - 0xffffffc4ff000000   (6144 kB)
[    0.000000]       pci io : 0xffffffc4ff000000 - 0xffffffc500000000   (  16 MB)
[    0.000000]      vmemmap : 0xffffffc500000000 - 0xffffffc600000000   (4096 MB)
[    0.000000]      vmalloc : 0xffffffc600000000 - 0xffffffd600000000   (  64 GB)
[    0.000000]      modules : 0xffffffff01f8a000 - 0xffffffff80000000   (2016 MB)
[    0.000000]       lowmem : 0xffffffd600000000 - 0xffffffd60c000000   ( 192 MB)
[    0.000000]       kernel : 0xffffffff80000000 - 0xffffffffffffffff   (2047 MB)
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1
[    0.000000] rcu: Hierarchical RCU implementation..
[    0.000000] rcu: .RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=2..
[    0.000000] rcu: .RCU debug extended QS entry/exit..
[    0.000000] .Tracing variant of Tasks RCU enabled..
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies..
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2
[    0.000000] RCU Tasks Trace: Setting shift to 1 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=2..
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] riscv-intc: 64 local interrupts mapped
[    0.000000] riscv: providing IPIs using SBI IPI extension
[    0.000000] rcu: srcu_init: Setting srcu_struct sizes based on contention..
[    0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x1623fa770, max_idle_ns: 3526361617904 ns
[    0.000034] sched_clock: 64 bits at 750kHz, resolution 1333ns, wraps every 4398046510524ns
[    0.003650] Console: colour dummy device 80x25
[    0.005023] Calibrating delay loop (skipped), value calculated using timer frequency.. 1.50 BogoMIPS (lpj=3000)
[    0.005686] pid_max: default: 32768 minimum: 301
[    0.007667] LSM: initializing lsm=capability
[    0.011774] Mount-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[    0.012403] Mountpoint-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
[    0.083258] riscv: ELF compat mode unsupported
[    0.083491] ASID allocator disabled (0 bits)
[    0.092565] rcu: Hierarchical SRCU implementation..
[    0.092947] rcu: .Max phase no-delay instances is 1000..
[    0.104523] Timer migration: 1 hierarchy levels; 8 children per group; 1 crossnode level
[    0.118241] smp: Bringing up secondary CPUs ....
[    0.142123] smp: Brought up 1 node, 2 CPUs
[    0.155791] Memory: 140304K/196608K available (9655K kernel code, 5038K rwdata, 4096K rodata, 12443K init, 473K bss, 54228K reserved, 0K cma-reserved)
[    0.167413] devtmpfs: initialized
[    0.204161] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[    0.204867] futex hash table entries: 512 (order: 3, 32768 bytes, linear)
[    0.211874] pinctrl core: initialized pinctrl subsystem
[    0.243477] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[    0.251286] DMA: preallocated 128 KiB GFP_KERNEL pool for atomic allocations
[    0.252615] DMA: preallocated 128 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
[    0.253958] audit: initializing netlink subsys (disabled)
[    0.260095] audit: type=2000 audit(0.240:1): state=initialized audit_enabled=0 res=1
[    0.271941] thermal_sys: Registered thermal governor 'step_wise'
[    0.273898] cpuidle: using governor menu
[    0.343495] cpu1: Ratio of byte access time to unaligned word access is 0.01, unaligned accesses are slow
[    0.402999] cpu0: Ratio of byte access time to unaligned word access is 0.01, unaligned accesses are slow
[    0.448095] HugeTLB: registered 2.00 MiB page size, pre-allocated 0 pages
[    0.448522] HugeTLB: 28 KiB vmemmap can be freed for a 2.00 MiB page
[    0.471537] iommu: Default domain type: Translated
[    0.471933] iommu: DMA domain TLB invalidation policy: strict mode
[    0.486763] SCSI subsystem initialized
[    0.497833] usbcore: registered new interface driver usbfs
[    0.499065] usbcore: registered new interface driver hub
[    0.500433] usbcore: registered new device driver usb
[    0.518014] Advanced Linux Sound Architecture Driver Initialized..
[    0.536761] vgaarb: loaded
[    0.546155] clocksource: Switched to clocksource riscv_clocksource
[    0.902470] NET: Registered PF_INET protocol family
[    0.907187] IP idents hash table entries: 4096 (order: 3, 32768 bytes, linear)
[    0.930749] tcp_listen_portaddr_hash hash table entries: 128 (order: 0, 4096 bytes, linear)
[    0.931534] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear)
[    0.932377] TCP established hash table entries: 2048 (order: 2, 16384 bytes, linear)
[    0.934041] TCP bind hash table entries: 2048 (order: 5, 131072 bytes, linear)
[    0.938603] TCP: Hash tables configured (established 2048 bind 2048)
[    0.940945] UDP hash table entries: 256 (order: 2, 24576 bytes, linear)
[    0.942849] UDP-Lite hash table entries: 256 (order: 2, 24576 bytes, linear)
[    0.947679] NET: Registered PF_UNIX/PF_LOCAL protocol family
[    0.963981] RPC: Registered named UNIX socket transport module..
[    0.964418] RPC: Registered udp transport module..
[    0.964734] RPC: Registered tcp transport module..
[    0.965029] RPC: Registered tcp-with-tls transport module..
[    0.965337] RPC: Registered tcp NFSv4.1 backchannel transport module..
[    0.966321] PCI: CLS 0 bytes, default 64
[    0.991770] workingset: timestamp_bits=46 max_order=16 bucket_order=0
[    1.020150] NFS: Registering the id_resolver key type
[    1.022294] Key type id_resolver registered
[    1.022710] Key type id_legacy registered
[    1.023953] nfs4filelayout_init: NFSv4 File Layout Driver Registering....
[    1.024418] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering....
[    1.038890] 9p: Installing v9fs 9p2000 file system support
[    1.045287] NET: Registered PF_ALG protocol family
[    1.047975] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 245)
[    1.054423] io scheduler mq-deadline registered
[    1.054861] io scheduler kyber registered
[    1.056434] io scheduler bfq registered
[    1.094555] riscv-plic: interrupt-controller@c000000: mapped 8 interrupts with 2 handlers for 4 contexts..
[    3.051354] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[    3.093922] of_serial 60010000.serial: error -ENXIO: IRQ index 0 not found
[    3.102142] printk: legacy console [ttyS0] disabled
[    3.111492] 60010000.serial: ttyS0 at MMIO 0x60010000 (irq = 0, base_baud = 4687500) is a 16550A
[    3.112328] printk: legacy console [ttyS0] enabled
[    3.304437] loop: module loaded
[    3.383757] e1000e: Intel(R) PRO/1000 Network Driver
[    3.384370] e1000e: Copyright(c) 1999 - 2015 Intel Corporation..
[    3.400480] usbcore: registered new interface driver uas
[    3.402661] usbcore: registered new interface driver usb-storage
[    3.408625] mousedev: PS/2 mouse device common for all mice
[    3.428426] sdhci: Secure Digital Host Controller Interface driver
[    3.429105] sdhci: Copyright(c) Pierre Ossman
[    3.431158] Synopsys Designware Multimedia Card Interface Driver
[    3.435436] sdhci-pltfm: SDHCI platform and OF driver helper
[    3.443049] usbcore: registered new interface driver usbhid
[    3.443733] usbhid: USB HID core driver
[    3.449310] riscv-pmu-sbi: SBI PMU extension is available
[    3.450856] riscv-pmu-sbi: 16 firmware and 2 hardware counters
[    3.451526] riscv-pmu-sbi: Perf sampling/filtering is not supported as sscof extension is not available
[    3.485136] NET: Registered PF_INET6 protocol family
[    3.514918] Segment Routing with IPv6
[    3.517160] In-situ OAM (IOAM) with IPv6
[    3.519766] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
[    3.534369] NET: Registered PF_PACKET protocol family
[    3.537177] 9pnet: Installing 9P2000 support
[    3.540004] Key type dns_resolver registered
[    4.135445] debug_vm_pgtable: [debug_vm_pgtable         ]: Validating architecture page table helpers
[    4.159368] clk: Disabling unused clocks
[    4.159982] PM: genpd: Disabling unused power domains
[    4.160802] ALSA device list:
[    4.161292]   No soundcards found..
[   16.187606] Freeing unused kernel image (initmem) memory: 12440K
[   16.189440] Run /sbin/init as init process
can't open /dev/null: No such file or directory
can't open /dev/null: No such file or directory
Saving 256 bits of non-creditable seed for next boot
Starting syslogd: OK
Starting klogd: OK
Running sysctl: OK
Starting network: OK
Starting crond: OK
..
Welcome to Buildroot
buildroot login:

Two scenarios are recorded: a two-hart Rocket RV64 system booting SMP Linux (the default), and a CVA6 RV32 system booting Linux 6.12 - on the CVA6 the replay includes the login and a first command on the recorded console. Switching scenarios resets the replay to its known starting point, and board controls that would change the flow are visibly disabled: this page talks to no board, no server and no network.

For the encoder behind this - protocols, compressions, resource figures and the verification story - see the CTTE overview.

Accemic Technologies GmbH is not affiliated with, endorsed by, or certified by RISC-V International. RISC-V is a trademark of RISC-V International. The other marks named on this page are attributed on our trademarks page.