feat(kernel): screen=boot keeps the console on the screen until login -- for watching a PC boot

KernelArgs gains screen_boot; cmdline.c parses screen=boot (with or without --; any other value:
off). With it, the v4 boot keeps the console mirrored to the framebuffer after POST, with the TTF
font, and says 'Screen: the console stays on until login (screen=boot)'; login and logout work as
without it, and nothing can be typed without Zuse. Without it, unchanged. For the SER5, which has
no known serial port (ruled 2026-10-28). BRINGUP.md: the smoke test's stick and starforth.cfg.

Tests: screen_boot (new) failed on amd64 and aarch64 before, passes on all three ISAs after;
screen_dark_until_login, screen_dark_after_logout, zuse pass. Acceptance: amd64, aarch64, riscv64 to
[zuse@Hera] ok>, POST 538/538, dict_hash 0xfec8c47cfc6f437f; v4 suite and test-32 0 failures.

Plan: docs/v4.0.0/plans/2026-10-27-stick-4-one-disk.md, Task 5.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
rajames
2026-10-28 17:50:10 -04:00
co-authored by Claude Opus 5.5
parent 1e8a6fed34
commit 954b4d5f70
27 changed files with 1784 additions and 4 deletions
+11
View File
@@ -187,6 +187,7 @@ void cmdline_parse_ascii(const char *cmdline, KernelArgs *args) {
args->run_doe = KARGS_DEFAULT_RUN_DOE;
args->log_level = KARGS_DEFAULT_LOG_LEVEL;
args->system = KARGS_SYSTEM_DEFAULT;
args->screen_boot = 0;
args->raw[0] = '\0';
if (!cmdline || !*cmdline) return;
@@ -216,6 +217,16 @@ void cmdline_parse_ascii(const char *cmdline, KernelArgs *args) {
if (v == '3') args->system = KARGS_SYSTEM_V3;
else if (v == '4') args->system = KARGS_SYSTEM_V4;
/* screen=boot, with or without "--": the console stays on the
* screen from POST until the first login, for watching a PC boot
* that has no serial port (2026-10-28; plan
* 2026-10-27-stick-4-one-disk.md, Task 5). Any other value: off. */
} else if ((tok_len >= 7 && sf_strncmp(tok, "screen=", 7) == 0) ||
(tok_len >= 9 && sf_strncmp(tok, "--screen=", 9) == 0)) {
const char *v = tok[0] == '-' ? tok + 9 : tok + 7;
unsigned int vlen = tok_len - (unsigned int)(v - tok);
args->screen_boot = vlen == 4 && sf_strncmp(v, "boot", 4) == 0;
/* --log-level=<level> (prefix = 12 chars) */
} else if (tok_len > 12 && sf_strncmp(tok, "--log-level=", 12) == 0) {
args->log_level = parse_log_level(tok + 12);