Patrick Georgi (pgeorgi@google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9088
-gerrit
commit d0254d5c92fbd27701220c97eca58028a2b92c37 Author: Aaron Durbin adurbin@chromium.org Date: Tue Sep 16 22:23:57 2014 -0500
arm64: exception handler registration
In order to build upon the arm64 exception handlers need to be registered. This provides very basic support to register a handler for a specific exception vector.
BUG=chrome-os-partner:30785 BRANCH=None TEST=Built and booted into kernel.
Change-Id: If046f0736765a2efeb23201c1d2d1f7f7db47dd2 Signed-off-by: Patrick Georgi pgeorgi@chromium.org Original-Commit-Id: a82e5e8d5900ebef16abdb68701be6beeb9ca13a Original-Change-Id: I0f68a48101ff48d582f5422871b9e7e5164357e4 Original-Signed-off-by: Aaron Durbin adurbin@chromium.org Original-Reviewed-on: https://chromium-review.googlesource.com/218650 Original-Reviewed-by: Furquan Shaikh furquan@chromium.org --- src/arch/arm64/armv8/exception.c | 191 +++++++++++++++++--------- src/arch/arm64/include/arch/transition.h | 18 +++ src/arch/arm64/include/armv8/arch/exception.h | 31 +++++ src/arch/arm64/transition_asm.S | 32 ++--- 4 files changed, 189 insertions(+), 83 deletions(-)
diff --git a/src/arch/arm64/armv8/exception.c b/src/arch/arm64/armv8/exception.c index 0aef0e5..a633e3a 100644 --- a/src/arch/arm64/armv8/exception.c +++ b/src/arch/arm64/armv8/exception.c @@ -29,56 +29,30 @@
#include <stdint.h> #include <types.h> +#include <arch/barrier.h> #include <arch/cache.h> #include <arch/exception.h> #include <arch/transition.h> #include <console/console.h> #include <arch/lib_helpers.h>
-static unsigned int test_exc; - -struct exception_handler_info -{ - const char *name; -}; - -enum { - EXC_SYNC_SP0 = 0, - EXC_IRQ_SP0, - EXC_FIQ_SP0, - EXC_SERROR_SP0, - EXC_SYNC_SP3, - EXC_IRQ_SP3, - EXC_FIQ_SP3, - EXC_SERROR_SP3, - EXC_SYNC_ELX_64, - EXC_IRQ_ELX_64, - EXC_FIQ_ELX_64, - EXC_SERROR_ELX_64, - EXC_SYNC_ELX_32, - EXC_IRQ_ELX_32, - EXC_FIQ_ELX_32, - EXC_SERROR_ELX_32, - EXC_COUNT -}; - -static struct exception_handler_info exceptions[EXC_COUNT] = { - [EXC_SYNC_SP0] = { "_sync_sp_el0" }, - [EXC_IRQ_SP0] = { "_irq_sp_el0" }, - [EXC_FIQ_SP0] = { "_fiq_sp_el0" }, - [EXC_SERROR_SP0] = {"_serror_sp_el0"}, - [EXC_SYNC_SP3] = { "_sync_sp_el3" }, - [EXC_IRQ_SP3] = { "_irq_sp_el3" }, - [EXC_FIQ_SP3] = { "_fiq_sp_el3" }, - [EXC_SERROR_SP3] = {"_serror_sp_el3"}, - [EXC_SYNC_ELX_64] = { "_sync_elx_64" }, - [EXC_IRQ_ELX_64] = { "_irq_elx_64" }, - [EXC_FIQ_ELX_64] = { "_fiq_elx_64" }, - [EXC_SERROR_ELX_64] = {"_serror_elx_64"}, - [EXC_SYNC_ELX_32] = { "_sync_elx_32" }, - [EXC_IRQ_ELX_32] = { "_irq_elx_32" }, - [EXC_FIQ_ELX_32] = { "_fiq_elx_32" }, - [EXC_SERROR_ELX_32] = {"_serror_elx_32"}, +static const char *exception_names[NUM_EXC_VIDS] = { + [EXC_VID_CUR_SP_EL0_SYNC] = "_sync_sp_el0", + [EXC_VID_CUR_SP_EL0_IRQ] = "_irq_sp_el0", + [EXC_VID_CUR_SP_EL0_FIRQ] = "_fiq_sp_el0", + [EXC_VID_CUR_SP_EL0_SERR] = "_serror_sp_el0", + [EXC_VID_CUR_SP_ELX_SYNC] = "_sync_sp_el3", + [EXC_VID_CUR_SP_ELX_IRQ] = "_irq_sp_el3", + [EXC_VID_CUR_SP_ELX_FIQ] = "_fiq_sp_el3", + [EXC_VID_CUR_SP_ELX_SERR] = "_serror_sp_el3", + [EXC_VID_LOW64_SYNC] = "_sync_elx_64", + [EXC_VID_LOW64_IRQ] = "_irq_elx_64", + [EXC_VID_LOW64_FIQ] = "_fiq_elx_64", + [EXC_VID_LOW64_SERR] = "_serror_elx_64", + [EXC_VID_LOW32_SYNC] = "_sync_elx_32", + [EXC_VID_LOW32_IRQ] = "_irq_elx_32", + [EXC_VID_LOW32_FIQ] = "_fiq_elx_32", + [EXC_VID_LOW32_SERR] = "_serror_elx_32" };
static void print_regs(struct exc_state *exc_state) @@ -98,39 +72,122 @@ static void print_regs(struct exc_state *exc_state) printk(BIOS_DEBUG, "X%02d = 0x%016llx\n", i, regs->x[i]); }
-void exc_dispatch(struct exc_state *exc_state, uint64_t idx) + +static struct exception_handler *handlers[NUM_EXC_VIDS]; + + +int exception_handler_register(uint64_t vid, struct exception_handler *h) { - if (idx >= EXC_COUNT) { - printk(BIOS_DEBUG, "Bad exception index %lx.\n", - (unsigned long)idx); - } else { - struct exception_handler_info *info = &exceptions[idx]; - - if (info->name) - printk(BIOS_DEBUG, "exception %s\n", info->name); - else - printk(BIOS_DEBUG, "exception _not_used.\n"); + if (vid >= NUM_EXC_VIDS) + return -1; + + /* Just place at head of queue. */ + h->next = handlers[vid]; + store_release(&handlers[vid], h); + + return 0; +} + +int exception_handler_unregister(uint64_t vid, struct exception_handler *h) +{ + struct exception_handler *cur; + struct exception_handler **prev; + + if (vid >= NUM_EXC_VIDS) + return -1; + + prev = &handlers[vid]; + + for (cur = handlers[vid]; cur != NULL; cur = cur->next) { + if (cur != h) + continue; + /* Update previous pointer. */ + store_release(prev, cur->next); + return 0; } - print_regs(exc_state);
- if (test_exc) { - exc_state->elx.elr += 4; - raw_write_elr_current(exc_state->elx.elr); - test_exc = 0; - printk(BIOS_DEBUG, "new ELR = 0x%016llx\n", exc_state->elx.elr); - } else - die("exception"); + /* Not found */ + return -1; +} + +static void print_exception_info(struct exc_state *state, uint64_t idx) +{ + if (idx < NUM_EXC_VIDS) + printk(BIOS_DEBUG, "exception %s\n", exception_names[idx]); + + print_regs(state); +}
- exc_exit(&exc_state->regs); +static void print_exception_and_die(struct exc_state *state, uint64_t idx) +{ + print_exception_info(state, idx); + die("exception death"); +} + + +static int handle_exception(struct exc_state *state, uint64_t idx) +{ + int ret = EXC_RET_ABORT; + + struct exception_handler *h; + + for (h = handlers[idx]; h != NULL; h = h->next) { + int hret; + + hret = h->handler(state, idx); + + if (hret > ret) + ret = hret; + } + + return ret; +} + +void exc_dispatch(struct exc_state *state, uint64_t idx) +{ + int ret; + + if (idx >= NUM_EXC_VIDS) { + printk(BIOS_DEBUG, "Bad exception index %x.\n", (int)idx); + print_exception_and_die(state, idx); + } + + ret = handle_exception(state, idx); + + if (ret == EXC_RET_ABORT) + print_exception_and_die(state, idx); + + if (ret == EXC_RET_IGNORED || ret == EXC_RET_HANDLED_DUMP_STATE) + print_exception_info(state, idx); + + exc_exit(&state->regs); +} + + +static int test_exception_handler(struct exc_state *state, uint64_t vector_id) +{ + /* Update instruction pointer to next instrution. */ + state->elx.elr += sizeof(uint32_t); + raw_write_elr_current(state->elx.elr); + return EXC_RET_HANDLED; }
static uint64_t test_exception(void) { - uint64_t *a = (uint64_t *)0xfffffffff0000000ULL; + struct exception_handler sync_elx; + struct exception_handler sync_el0; + unsigned long long *a = (void *)0xffffffff00000000ULL; + + sync_elx.handler = &test_exception_handler; + sync_el0.handler = &test_exception_handler; + + exception_handler_register(EXC_VID_CUR_SP_ELX_SYNC, &sync_elx); + exception_handler_register(EXC_VID_CUR_SP_EL0_SYNC, &sync_el0);
- test_exc = 1; + force_read(*a);
- printk(BIOS_DEBUG, "%llx\n", *a); + exception_handler_unregister(EXC_VID_CUR_SP_ELX_SYNC, &sync_elx); + exception_handler_unregister(EXC_VID_CUR_SP_EL0_SYNC, &sync_el0);
return 0; } diff --git a/src/arch/arm64/include/arch/transition.h b/src/arch/arm64/include/arch/transition.h index e8ded5f..9da6b36 100644 --- a/src/arch/arm64/include/arch/transition.h +++ b/src/arch/arm64/include/arch/transition.h @@ -42,6 +42,24 @@ #define STACK_POP_BYTES 16 #define STACK_PUSH_BYTES -16
+#define EXC_VID_CUR_SP_EL0_SYNC 0 +#define EXC_VID_CUR_SP_EL0_IRQ 1 +#define EXC_VID_CUR_SP_EL0_FIRQ 2 +#define EXC_VID_CUR_SP_EL0_SERR 3 +#define EXC_VID_CUR_SP_ELX_SYNC 4 +#define EXC_VID_CUR_SP_ELX_IRQ 5 +#define EXC_VID_CUR_SP_ELX_FIQ 6 +#define EXC_VID_CUR_SP_ELX_SERR 7 +#define EXC_VID_LOW64_SYNC 8 +#define EXC_VID_LOW64_IRQ 9 +#define EXC_VID_LOW64_FIQ 10 +#define EXC_VID_LOW64_SERR 11 +#define EXC_VID_LOW32_SYNC 12 +#define EXC_VID_LOW32_IRQ 13 +#define EXC_VID_LOW32_FIQ 14 +#define EXC_VID_LOW32_SERR 15 +#define NUM_EXC_VIDS 16 + #ifndef __ASSEMBLY__
#include <stdint.h> diff --git a/src/arch/arm64/include/armv8/arch/exception.h b/src/arch/arm64/include/armv8/arch/exception.h index 11ffcb6..49ea747 100644 --- a/src/arch/arm64/include/armv8/arch/exception.h +++ b/src/arch/arm64/include/armv8/arch/exception.h @@ -30,8 +30,39 @@ #ifndef _ARCH_EXCEPTION_H #define _ARCH_EXCEPTION_H
+#include <arch/transition.h> + /* Initialize the exception handling on the current CPU. */ void exception_hwinit(void); void exception_init(void);
+/* + * Order matters for handling return values. The larger the value the higher + * the precedence. + */ +enum { + EXC_RET_IGNORED, + EXC_RET_ABORT, + EXC_RET_HANDLED, + EXC_RET_HANDLED_DUMP_STATE, +}; + +struct exception_handler { + int (*handler)(struct exc_state *state, uint64_t vector_id); + struct exception_handler *next; +}; + + +/* + * Register a handler provided with the associated vector id. Returns 0 on + * sucess, < 0 on error. Note that registration is not thread/interrupt safe. + */ +int exception_handler_register(uint64_t vid, struct exception_handler *h); + +/* + * Unregister a handler from the vector id. Return 0 on success, < 0 on error. + * Note that the unregistration is not thread/interrupt safe. + */ +int exception_handler_unregister(uint64_t vid, struct exception_handler *h); + #endif diff --git a/src/arch/arm64/transition_asm.S b/src/arch/arm64/transition_asm.S index 9f48549..111efe0 100644 --- a/src/arch/arm64/transition_asm.S +++ b/src/arch/arm64/transition_asm.S @@ -77,22 +77,22 @@ */ ENTRY_WITH_ALIGN(exc_vectors, 11)
-eentry sync_curr_sp0,#0 -eentry irq_curr_sp0,#1 -eentry fiq_curr_sp0,#2 -eentry serror_curr_sp0,#3 -eentry sync_curr_spx,#4 -eentry irq_curr_spx,#5 -eentry fiq_curr_spx,#6 -eentry serror_curr_spx,#7 -eentry sync_lower_64,#8 -eentry irq_lower_64,#9 -eentry fiq_lower_64,#10 -eentry serror_lower_64,#11 -eentry sync_lower_32,#12 -eentry irq_lower_32,#13 -eentry fiq_lower_32,#14 -eentry serror_lower_32,#15 +eentry sync_curr_sp0, #EXC_VID_CUR_SP_EL0_SYNC +eentry irq_curr_sp0, #EXC_VID_CUR_SP_EL0_IRQ +eentry fiq_curr_sp0, #EXC_VID_CUR_SP_EL0_FIRQ +eentry serror_curr_sp0, #EXC_VID_CUR_SP_EL0_SERR +eentry sync_curr_spx, #EXC_VID_CUR_SP_ELX_SYNC +eentry irq_curr_spx, #EXC_VID_CUR_SP_ELX_IRQ +eentry fiq_curr_spx, #EXC_VID_CUR_SP_ELX_FIQ +eentry serror_curr_spx, #EXC_VID_CUR_SP_ELX_SERR +eentry sync_lower_64, #EXC_VID_LOW64_SYNC +eentry irq_lower_64, #EXC_VID_LOW64_IRQ +eentry fiq_lower_64, #EXC_VID_LOW64_FIQ +eentry serror_lower_64, #EXC_VID_LOW64_SERR +eentry sync_lower_32, #EXC_VID_LOW32_SYNC +eentry irq_lower_32, #EXC_VID_LOW32_IRQ +eentry fiq_lower_32, #EXC_VID_LOW32_FIQ +eentry serror_lower_32, #EXC_VID_LOW32_SERR
ENDPROC(exc_vectors)