libpayload/x86/exception: Add ability to handle user defined interrupts

I need to setup the APIC timer to fire interrupts. I would like to reuse
the existing interrupt table. So I extended it to support user defined
interrupts. I just added all 255 vectors so there wouldn't need to be
any additional build time configuration.

I'm going to deprecate exception_install_hook and remove it in a follow
up. It will be replaced with set_interrupt_handler. This way the
exception lookup does not have to manage a list of callbacks, or have to
worry about the order they are processed.

BUG=b:109749762
TEST=Wrote an interrupt handler and fired an APIC timer interrupt and
verified that vector 32 was returned.

Change-Id: Id9c2583c7c3d9be4a06a25e546e64399f2b0620c
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://review.coreboot.org/28100
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
This commit is contained in:
Raul E Rangel 2018-08-22 10:03:05 -06:00 committed by Patrick Georgi
parent 28cee59ca2
commit 80d5c19590
3 changed files with 47 additions and 1 deletions

View File

@ -37,6 +37,9 @@
u32 exception_stack[0x400] __attribute__((aligned(8)));
static exception_hook hook;
static interrupt_handler handlers[256];
static const char *names[EXC_COUNT] = {
[EXC_DE] = "Divide by Zero",
[EXC_DB] = "Debug",
@ -163,7 +166,16 @@ static void dump_exception_state(void)
void exception_dispatch(void)
{
u32 vec = exception_state->vector;
die_if(vec >= EXC_COUNT || !names[vec], "Bad exception vector %u", vec);
die_if(vec >= ARRAY_SIZE(handlers), "Invalid vector %u\n", vec);
if (handlers[vec]) {
handlers[vec](vec);
return;
}
die_if(vec >= EXC_COUNT || !names[vec], "Bad exception vector %u\n",
vec);
if (hook && hook(vec))
return;
@ -185,6 +197,11 @@ void exception_install_hook(exception_hook h)
hook = h;
}
void set_interrupt_handler(u8 vector, interrupt_handler handler)
{
handlers[vector] = handler;
}
static uint32_t eflags(void)
{
uint32_t eflags;

View File

@ -68,6 +68,14 @@ exception_stub_\num:
jmp exception_common
.endm
.altmacro
.macro user_defined_stubs from, to
stub \from
.if \to-\from
user_defined_stubs %(from+1),\to
.endif
.endm
stub 0
stub 1
stub 2
@ -100,6 +108,11 @@ exception_stub_\num:
stub 29
stub_err 30
stub 31
/* Split the macro so we avoid a stack overflow. */
user_defined_stubs 32, 63
user_defined_stubs 64, 127
user_defined_stubs 128, 191
user_defined_stubs 192, 255
exception_common:
/*
@ -215,6 +228,14 @@ gdt_ptr:
.long \target
.endm
.altmacro
.macro user_defined_gates from, to
interrupt_gate exception_stub_\from
.if \to-\from
user_defined_gates %(from+1),\to
.endif
.endm
.align 8
.global idt
idt:
@ -250,6 +271,10 @@ idt:
interrupt_gate exception_stub_29
interrupt_gate exception_stub_30
interrupt_gate exception_stub_31
user_defined_gates 32, 63
user_defined_gates 64, 127
user_defined_gates 128, 191
user_defined_gates 192, 255
idt_end:
/* IDT pointer for use with lidt */

View File

@ -36,6 +36,10 @@
typedef int (*exception_hook)(u32 type);
void exception_init(void);
/* Deprecated, use set_interrupt_handler. */
void exception_install_hook(exception_hook h);
typedef void (*interrupt_handler)(u8 vector);
void set_interrupt_handler(u8 vector, interrupt_handler handler);
#endif