From 80d5c195901d7fa1a442b36d697f9f0f3f063379 Mon Sep 17 00:00:00 2001 From: Raul E Rangel Date: Wed, 22 Aug 2018 10:03:05 -0600 Subject: 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 Reviewed-on: https://review.coreboot.org/28100 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth --- payloads/libpayload/arch/x86/exception.c | 19 ++++++++++++++++++- payloads/libpayload/arch/x86/exception_asm.S | 25 +++++++++++++++++++++++++ payloads/libpayload/include/exception.h | 4 ++++ 3 files changed, 47 insertions(+), 1 deletion(-) diff --git a/payloads/libpayload/arch/x86/exception.c b/payloads/libpayload/arch/x86/exception.c index fe50d09c51..d70d942a05 100644 --- a/payloads/libpayload/arch/x86/exception.c +++ b/payloads/libpayload/arch/x86/exception.c @@ -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; diff --git a/payloads/libpayload/arch/x86/exception_asm.S b/payloads/libpayload/arch/x86/exception_asm.S index a8f9a1d254..00dc888207 100644 --- a/payloads/libpayload/arch/x86/exception_asm.S +++ b/payloads/libpayload/arch/x86/exception_asm.S @@ -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 */ diff --git a/payloads/libpayload/include/exception.h b/payloads/libpayload/include/exception.h index 67923ea9af..7a7bc46d26 100644 --- a/payloads/libpayload/include/exception.h +++ b/payloads/libpayload/include/exception.h @@ -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 -- cgit v1.2.3