From 81218e2fd9442ce2cbc901b7f6d2b3df3f705bba Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Wed, 3 May 2023 10:31:23 +0200
Subject: [PATCH] add hwerr_printf function for threads

RH-Author: Gerd Hoffmann <None>
RH-MergeRequest: 6: log error message to screen when booting with (unsupported) 4k sectors
RH-Jira: RHEL-7110
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [1/2] 37f3d1b45b289e4efb18817c265be2bff2606ebb (kraxel.rh/centos-src-seabios)

Printing to the screen from threads doesn't work, because that involves
a switch to real mode for using int10h services.

Add a string buffer and hwerr_printf() helper functions to store error
messages. Print the buffer later, after device initialization, from main
thread in case it is not empty.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

Patch-name: seabios-add-hwerr_printf-function-for-threads.patch
Patch-id: 1
Patch-present-in-specfile: True
---
 src/output.c | 17 +++++++++++++++++
 src/output.h |  5 +++++
 src/post.c   |  4 ++++
 3 files changed, 26 insertions(+)

diff --git a/src/output.c b/src/output.c
index 0184444c..8c9d6b8f 100644
--- a/src/output.c
+++ b/src/output.c
@@ -419,6 +419,23 @@ snprintf(char *str, size_t size, const char *fmt, ...)
     return end - str;
 }
 
+char hwerror_str[512];
+struct snprintfinfo hwerror_info = {
+    .info  = { putc_str },
+    .str   = hwerror_str,
+    .end   = hwerror_str + sizeof(hwerror_str) - 1,
+};
+
+void
+hwerr_printf(const char *fmt, ...)
+{
+    ASSERT32FLAT();
+    va_list args;
+    va_start(args, fmt);
+    bvprintf(&hwerror_info.info, fmt, args);
+    va_end(args);
+}
+
 // Build a formatted string - malloc'ing the memory.
 char *
 znprintf(size_t size, const char *fmt, ...)
diff --git a/src/output.h b/src/output.h
index 14288cf5..4548d2d4 100644
--- a/src/output.h
+++ b/src/output.h
@@ -16,6 +16,11 @@ char * znprintf(size_t size, const char *fmt, ...)
     __attribute__ ((format (printf, 2, 3)));
 void __dprintf(const char *fmt, ...)
     __attribute__ ((format (printf, 1, 2)));
+
+extern char hwerror_str[512];
+void hwerr_printf(const char *fmt, ...)
+    __attribute__ ((format (printf, 1, 2)));
+
 struct bregs;
 void __debug_enter(struct bregs *regs, const char *fname);
 void __debug_isr(const char *fname);
diff --git a/src/post.c b/src/post.c
index f93106a1..3e85da43 100644
--- a/src/post.c
+++ b/src/post.c
@@ -216,6 +216,10 @@ maininit(void)
         device_hardware_setup();
         wait_threads();
     }
+    if (hwerror_str[0])
+        printf("\n"
+               "hardware setup errors:\n"
+               "%s", hwerror_str);
 
     // Run option roms
     optionrom_setup();