I have patched kernalemu to provide me with 6502 CPU INSN and cycle
counts during boot. Here is what to expect when you run release
v0.0.2. The two figures at the start of each line are the timings for
the respective previous line, in terms of INSNs and cycles (from the
fake6502 emulator underlying kernalemu):
C-64 SEMU RISC-V EMULATOR
[ 2163 6374] gIT COMMIT: $iD: 3DC721505BDB572B69C70BAB73B62C895D59FB7C $
[ 2637 7797] EMU STATE BEGIN: 86a6, SIZE: 002A
[ 6736 19433] VM STATE BEGIN: 85c8, SIZE: 00C3
[ 10863 31146] [ 0.000000] Linux version 6.1.49 (ok@ryzen) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2023.05.1) 12.3.0, GNU ld (GNU Binutils) 2.39) #1 Mon Aug 28 21:35:13 CEST 2023
[ 308119249 937013361] [ 0.000000] Machine model: semu
[ 310076614 942970684] [ 0.000000] earlycon: ns16550 at MMIO 0xf4000000 (options '')
[ 313056617 952045088] [ 0.000000] printk: bootconsole [ns16550] enabled
[ 317463477 965449118] [ 0.000000] Zone ranges:
[ 500494555 1523601187] [ 0.000000] Normal [mem 0x0000000000000000-0x0000000000bfffff]
[ 506723872 1542547329] [ 0.000000] Movable zone start for each node
[ 510134869 1552923070] [ 0.000000] Early memory node ranges
[ 513226893 1562327771] [ 0.000000] node 0: [mem 0x0000000000000000-0x0000000000bfffff]
[ 518686116 1578931662] [ 0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x0000000000bfffff]
[ 524437533 1596420701] [ 0.000000] SBI specification v0.3 detected
[ 615260388 1871503665] [ 0.000000] SBI implementation ID=0x999 Version=0x1
[ 619686958 1884965960] [ 0.000000] SBI TIME extension detected
[ 622958304 1894917918] [ 0.000000] SBI SRST extension detected
[ 626263105 1904971091] [ 0.000000] riscv: base ISA extensions aim
[ 632514919 1923990035] [ 0.000000] riscv: ELF capabilities aim
[ 636070976 1934805850] [ 0.000000] Built 1 zonelists, mobility grouping off. Total pages: 3048
[ 667308177 2029672815] [ 0.000000] Kernel command line: earlycon console=ttyS0 rootfstype=cramfs root=mtd0 phram.phram=mtd0,0x0c00000,0x400000
[ 674113494 2050376039] [ 0.000000] Dentry cache hash table entries: 2048 (order: 1, 8192 bytes, linear)
[ 707788591 2152743047] [ 0.000000] Inode-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 715481086 2176129529] [ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[ 720679889 2191947335] [ 0.000000] Memory: 7304K/12288K available (3296K kernel code, 336K rwdata, 861K rodata, 159K init, 168K bss, 4984K reserved, 0K cma-reserved)
[ 765920970 2328731289] [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 808979663 2459501377] [ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[ 839443737 2552057319] [ 0.000000] riscv-intc: 32 local interrupts mapped
[ 856182147 2602978194] [ 0.000000] plic: interrupt-controller@0: mapped 31 interrupts with 1 handlers for 1 contexts.
[ 959303980 2913966499] [ 0.000000] riscv-timer: riscv_timer_init_dt: Registering clocksource cpuid [0] hartid [0]
[ 972625781 2954493547] [ 0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0xefdb196da, max_idle_ns: 440795204367 ns
[ 985228669 2992822956] [ 0.000006] sched_clock: 64 bits at 65MHz, resolution 15ns, wraps every 2199023255550ns
[ 996053710 3025739301] [ 0.001222] Console: colour dummy device 80x25
[ 1027528875 3121713752] [ 0.001489] Calibrating delay loop (skipped), value calculated using timer frequency.. 130.00 BogoMIPS (lpj=650000)
[ 1038422333 3154876866] [ 0.001793] pid_max: default: 32768 minimum: 301
[ 1042711182 3167933048] [ 0.002981] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 1075976661 3269161859] [ 0.003247] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 1083439510 3291877850] [ 0.008485] ASID allocator disabled (0 bits)
[ 1227056928 3729316343] [ 0.010509] devtmpfs: initialized
[ 1281963224 3896566877] [ 0.016576] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[ 1460533193 4441386705] [ 0.016877] futex hash table entries: 256 (order: -1, 3072 bytes, linear)
[ 1467212372 4461722771] [ 0.026316] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[ 1693950120 5152197777] [ 0.057511] clocksource: Switched to clocksource riscv_clocksource
[ 2595257873 7902064614] [ 0.116797] NET: Registered PF_INET protocol family
[ 4206335359 12812861918] [ 0.118803] IP idents hash table entries: 2048 (order: 2, 16384 bytes, linear)
[ 4259090315 12973488131] [ 0.126628] tcp_listen_portaddr_hash hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 4460554898 13589261109] [ 0.127063] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear)
[ 4471469986 13622445171] [ 0.127350] TCP established hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 4480992280 13651430671] [ 0.127801] TCP bind hash table entries: 1024 (order: 1, 8192 bytes, linear)
[ 4490929304 13681665551] [ 0.128202] TCP: Hash tables configured (established 1024 bind 1024)
[ 4501562246 13714068668] [ 0.128700] UDP hash table entries: 256 (order: 0, 4096 bytes, linear)
[ 4516752063 13760342473] [ 0.129017] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes, linear)
[ 4525493550 13786944670] [ 0.130168] NET: Registered PF_UNIX/PF_LOCAL protocol family
[ 4554014463 13873779566] [ 0.134920] workingset: timestamp_bits=30 max_order=11 bucket_order=0
[ 4691360730 14292549786] [ 0.542897] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 15854471987 48327993843] [ 0.551164] printk: console [ttyS0] disabled
[ 16088472174 49041516957] [ 0.551466] f4000000.serial: ttyS0 at MMIO 0xf4000000 (irq = 1, base_baud = 312500) is a 16550
[ 16099820106 49076050244] [ 0.551812] printk: console [ttyS0] enabled
[ 16107798178 49100349808] [ 0.551812] printk: console [ttyS0] enabled
[ 16110291560 49107954778] [ 0.552110] printk: bootconsole [ns16550] disabled
[ 16116764036 49127673732] [ 0.552110] printk: bootconsole [ns16550] disabled
[ 16119495876 49136005967] [ 0.559418] phram: mtd0 device: 0x400000 at 0xc00000 for erasesize 0x1000
[ 16326463290 49767066870] [ 0.566120] cramfs: checking physical address 0x00000000 for linear cramfs image
[ 16514952166 50341294365] [ 0.566405] cramfs: linear cramfs image on mtd:mtd0 appears to be 3260 KB in size
[ 16523501654 50367344849] [ 0.566854] VFS: Mounted root (cramfs filesystem) readonly on device 31:0.
[ 16536442679 50406787709] [ 0.567317] devtmpfs: mounted
[ 16545440495 50434234629] [ 0.568472] Freeing unused kernel image (initmem) memory: 156K
[ 16582997299 50548673097] [ 0.568722] Kernel memory protection not selected by kernel config.
[ 16589886400 50569670084] [ 0.569018] Run /sbin/init as init process
[ 16596769491 50590653983] Starting syslogd: OK
[ 25451779402 77619840314] Starting klogd: OK
[ 27151136247 82808624155] Running sysctl: OK
[ 32470315218 99044736342] Starting network: OK
[ 38076669271 116164194512]
[ 41727918869 127302363903] Welcome to Buildroot
[ 41758779219 127396453645] buildroot login: root
[ 43605964984 133030343892] # pwd
[ 46426246175 141637349795] /root
[ 46441150281 141682834802] #
If you press any key during boot, timing might vary slightly due to the input handling. You need to divide the second figure by about a million to get real time in seconds on a C-64. The last part was done manually, of course, so your mileage will vary.
The numbers here are also all somewhat optimistic, as running it through
kernalemu does not count the cycles that the C-64 KERNAL spends in
IRQ handling and the I/O routines.
I uploaded a patched
kernalemu which is likely
the fastest way to boot an emulated Linux on an emulated 6502 for now.