From 6fdb223859959c5fe9392c0e5a34d6090cdeebeb Mon Sep 17 00:00:00 2001 From: Kyösti Mälkki Date: Tue, 5 Mar 2019 16:48:25 +0200 Subject: arch/x86: Refactor CAR_GLOBAL quirk for FSP1.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit These platforms return to romstage from FSP only after already having torn CAR down. A copy of the entire CAR region is available and discoverable via HOB. Previously, CBMEM console detected on-the-fly that CAR migration had happened and relocated cbmem_console_p accoringlin with car_sync_var(). However, if the CAR_GLOBAL pointing to another object inside CAR is a relative offset instead, we have a more generic solution that can be used with timestamps code as well. Change-Id: Ica877b47e68d56189e9d998b5630019d4328a419 Signed-off-by: Kyösti Mälkki Reviewed-on: https://review.coreboot.org/c/coreboot/+/35140 Reviewed-by: Aaron Durbin Tested-by: build bot (Jenkins) --- src/cpu/x86/car.c | 49 ++++++++++++++++++++++--------------------------- 1 file changed, 22 insertions(+), 27 deletions(-) (limited to 'src/cpu') diff --git a/src/cpu/x86/car.c b/src/cpu/x86/car.c index 6fc61686df..009ac192cc 100644 --- a/src/cpu/x86/car.c +++ b/src/cpu/x86/car.c @@ -77,41 +77,36 @@ void *car_get_var_ptr(void *var) return &migrated_base[offset]; } +#if CONFIG(PLATFORM_USES_FSP1_0) /* - * Update a CAR_GLOBAL variable var, originally pointing to CAR region, - * with the address in migrated CAR region in DRAM. + * When a CAR_GLOBAL points to target object inside CAR, use relative + * addressing. Such CAR_GLOBAL has to be expicitly accessed using + * car_set_reloc_ptr() and car_get_reloc_ptr() as the stored value is now + * an offset instead of the absolute address (pointer) of the target. + * + * This way discovery of objects that are not CAR_GLOBALs themselves, + * remain discoverable after CAR migration has implicitly happened. */ -void *car_sync_var_ptr(void *var) +void car_set_reloc_ptr(void *var, void *val) { - void **mig_var = car_get_var_ptr(var); - void *_car_start = _car_relocatable_data_start; - void *_car_end = _car_relocatable_data_end; + uintptr_t *offset = car_get_var_ptr(var); + *offset = 0; - /* Not moved or migrated yet. */ - if (mig_var == var) - return mig_var; - - /* - * Migrate the cbmem console pointer for FSP 1.0 platforms. Otherwise, - * keep console buffer in CAR until cbmemc_reinit() moves it. - */ - if (*mig_var == _preram_cbmem_console) { - if (CONFIG(PLATFORM_USES_FSP1_0)) - *mig_var += (char *)mig_var - (char *)var; - return mig_var; - } + if (val) + *offset = (uintptr_t)offset - (uintptr_t)val; +} - /* It's already pointing outside car.global_data. */ - if (*mig_var < _car_start || *mig_var > _car_end) - return mig_var; +void *car_get_reloc_ptr(void *var) +{ + uintptr_t *offset = car_get_var_ptr(var); + void *val = NULL; - /* Move the pointer by the same amount the variable storing it was - * moved by. - */ - *mig_var += (char *)mig_var - (char *)var; + if (*offset) + val = (void *)((uintptr_t)offset - *offset); - return mig_var; + return val; } +#endif int car_active(void) { -- cgit v1.2.3