From 092cac58dee8fb87e0615d060a9de0f7ec693ee4 Mon Sep 17 00:00:00 2001 From: Julius Werner Date: Thu, 15 May 2014 19:41:52 -0700 Subject: libpayload: Rework exception hook interface This patch makes some slight changes to the exception hook interface. The old code provides a different handler hook for every exception type... however, in practice all those hook functions often need to look very similar, so this creates more boilerplate than it removes. The new interface just allows for a single hook with the exception type passed as an argument, and the consumer can signal whether the exception was handled through the return value. (Right now this still only supports one consumer, but it could easily be extended to walk through a list of hooks if the need arises.) Also move the excepton state from an argument to a global. This avoids a lot of boilerplate since some consumers need to change the state from many places, so they would have to pass the same pointer around many times. It also removes the false suggestion that the exception state was not global and you could have multiple copies of it (which the exception core doesn't support for any architecture). On the ARM side, the exception state is separated from the exception stack for easier access. (This requires some assembly changes, and I threw in a few comments and corrected the immediate sigils from '$' to the official '#' while I'm there.) Since the exception state is now both stored and loaded through an indirection pointer, this allows for some very limited reentrance (you could point it to a different struct while handling an exception, and while you still won't be able to return to the outer-level exception from there, you could at least swap out the pointer and return back to System Mode in one go). BUG=chrome-os-partner:18390 TEST=Made sure normal exceptions still get dumped correctly on both archs. Original-Change-Id: I5d9a934fab7c14ccb2c9d7ee4b3465c825521fa2 Original-Signed-off-by: Julius Werner Original-Reviewed-on: https://chromium-review.googlesource.com/202562 Original-Reviewed-by: Stefan Reinauer (cherry picked from commit 97542110f0b385b9b8d89675866e65db8ca32aeb) Signed-off-by: Marc Jones *** Squashed to prevent build failures. *** libpayload: align arm64 with new exception handling model The exception handling was previously updated, however the arm64 changes raced with hat one. Make the arm64 align with the new model. Without these changes compilation will fail. BUG=None BRANCH=None TEST=Can build libpayload for rush. Original-Change-Id: I320b39a57b985d1f87446ea7757955664f8dba8f Original-Signed-off-by: Aaron Durbin Original-Reviewed-on: https://chromium-review.googlesource.com/204402 Original-Reviewed-by: Furquan Shaikh Original-Commit-Queue: Furquan Shaikh (cherry picked from commit 0080df41b311ef20f9214b386fa4e38ee54aa1a1) Signed-off-by: Marc Jones Change-Id: I9a0bb3848cf5286f9f4bb08172a9f4a15278348e Reviewed-on: http://review.coreboot.org/8117 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer --- payloads/libpayload/arch/arm64/exception.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'payloads/libpayload/arch/arm64') diff --git a/payloads/libpayload/arch/arm64/exception.c b/payloads/libpayload/arch/arm64/exception.c index 988bef9ed4..226f5ca27d 100644 --- a/payloads/libpayload/arch/arm64/exception.c +++ b/payloads/libpayload/arch/arm64/exception.c @@ -36,9 +36,10 @@ extern unsigned int test_exc; struct exception_handler_info { const char *name; - exception_hook hook; }; +static exception_hook hook; +struct exception_state *exception_state; static struct exception_handler_info exceptions[EXC_COUNT] = { [EXC_INV] = { "_invalid_exception" }, [EXC_SYNC] = { "_sync" }, @@ -61,14 +62,14 @@ static void print_regs(struct exception_state *state) void exception_dispatch(struct exception_state *state, int idx); void exception_dispatch(struct exception_state *state, int idx) { + exception_state = state; + if (idx >= EXC_COUNT) { printf("Bad exception index %d.\n", idx); } else { struct exception_handler_info *info = &exceptions[idx]; - if (info->hook) { - info->hook(idx, state); + if (hook && hook(idx)) return; - } if (info->name) printf("exception %s\n", info->name); @@ -89,8 +90,8 @@ void exception_init(void) set_vbar(exception_table); } -void exception_install_hook(int type, exception_hook hook) +void exception_install_hook(exception_hook h) { - die_if(type >= EXC_COUNT, "Out of bounds exception index %d.\n", type); - exceptions[type].hook = hook; + die_if(hook, "Implement support for a list of hooks if you need it."); + hook = h; } -- cgit v1.2.3