From 6c68e7adfa6255268a80522ea39dfef4aa20ca70 Mon Sep 17 00:00:00 2001 From: Kevin O'Connor Date: Sat, 19 Apr 2014 12:22:22 -0400 Subject: If an int 1587 call is made from an option rom, stay in bigreal mode. Modify the int 1587 handler to check if the POST phase is still running. If it is, use bigreal mode segment limits so that the caller remains in bigreal mode when the 1587 handler completes. This helps with SeaVGABIOS' use of "direct" framebuffer accesses (an option rom may attempt to display text during its option rom execution which can cause SeaVGABIOS to make the int 1587 calls). Signed-off-by: Kevin O'Connor --- src/misc.c | 9 +++++++++ src/post.c | 2 ++ src/resume.c | 3 --- src/system.c | 9 +++++---- src/util.h | 1 + 5 files changed, 17 insertions(+), 7 deletions(-) diff --git a/src/misc.c b/src/misc.c index 191e707..6712355 100644 --- a/src/misc.c +++ b/src/misc.c @@ -14,6 +14,15 @@ #define PORT_MATH_CLEAR 0x00f0 +// Indicator if POST phase has been started (and if it has completed). +int HaveRunPost VARFSEG; + +int +in_post(void) +{ + return GET_GLOBAL(HaveRunPost) == 1; +} + /**************************************************************** * Misc 16bit ISRs diff --git a/src/post.c b/src/post.c index 5fc1968..0d9e66f 100644 --- a/src/post.c +++ b/src/post.c @@ -185,6 +185,8 @@ prepareboot(void) malloc_prepboot(); memmap_prepboot(); + HaveRunPost = 2; + // Setup bios checksum. BiosChecksum -= checksum((u8*)BUILD_BIOS_ADDR, BUILD_BIOS_SIZE); } diff --git a/src/resume.c b/src/resume.c index e2ceef1..1903174 100644 --- a/src/resume.c +++ b/src/resume.c @@ -17,9 +17,6 @@ #include "string.h" // memset #include "util.h" // dma_setup -// Indicator if POST phase has been run. -int HaveRunPost VARFSEG; - // Handler for post calls that look like a resume. void VISIBLE16 handle_resume(void) diff --git a/src/system.c b/src/system.c index 5d10cc8..3cb2228 100644 --- a/src/system.c +++ b/src/system.c @@ -115,12 +115,13 @@ handle_1587(struct bregs *regs) SET_FARVAR(gdt_seg, gdt_far[1], GDT_DATA | GDT_LIMIT((6*sizeof(u64))-1) | GDT_BASE(loc)); // Initialize CS descriptor - SET_FARVAR(gdt_seg, gdt_far[4], GDT_CODE | GDT_LIMIT(BUILD_BIOS_SIZE-1) - | GDT_BASE(BUILD_BIOS_ADDR)); + u64 lim = GDT_LIMIT(0x0ffff); + if (in_post()) + lim = GDT_GRANLIMIT(0xffffffff); + SET_FARVAR(gdt_seg, gdt_far[4], GDT_CODE | lim | GDT_BASE(BUILD_BIOS_ADDR)); // Initialize SS descriptor loc = (u32)MAKE_FLATPTR(GET_SEG(SS), 0); - SET_FARVAR(gdt_seg, gdt_far[5], GDT_DATA | GDT_LIMIT(0x0ffff) - | GDT_BASE(loc)); + SET_FARVAR(gdt_seg, gdt_far[5], GDT_DATA | lim | GDT_BASE(loc)); u16 count = regs->cx; asm volatile( diff --git a/src/util.h b/src/util.h index 9557581..0cbea48 100644 --- a/src/util.h +++ b/src/util.h @@ -178,6 +178,7 @@ void process_key(u8 key); // misc.c extern struct bios_config_table_s BIOS_CONFIG_TABLE __aligned(1); extern u8 BiosChecksum; +int in_post(void); void mathcp_setup(void); // mouse.c -- cgit v1.1