From: Peter Hoyes Peter.Hoyes@arm.com
Use the environment variable armv8_switch_to_el1 to determine whether to switch to EL1 at runtime. This is an alternative to the CONFIG_ARMV8_SWITCH_TO_EL1 compile-time option.
The environment variable will be ineffective if the ARMV8_MULTIENTRY config is used.
This is required by the Armv8r64 architecture, which must be able to boot at S-EL1 for Linux but may need to boot at other ELs for other systems.
Signed-off-by: Peter Hoyes Peter.Hoyes@arm.com --- arch/arm/lib/bootm.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-)
diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c index f60ee3a7e6..ea9bfe7570 100644 --- a/arch/arm/lib/bootm.c +++ b/arch/arm/lib/bootm.c @@ -317,7 +317,6 @@ __weak void update_os_arch_secondary_cores(uint8_t os_arch) { }
-#ifdef CONFIG_ARMV8_SWITCH_TO_EL1 static void switch_to_el1(void) { if ((IH_ARCH_DEFAULT == IH_ARCH_ARM64) && @@ -332,7 +331,6 @@ static void switch_to_el1(void) ES_TO_AARCH64); } #endif -#endif
/* Subcommand: GO */ static void boot_jump_linux(bootm_headers_t *images, int flag) @@ -359,21 +357,33 @@ static void boot_jump_linux(bootm_headers_t *images, int flag)
update_os_arch_secondary_cores(images->os.arch);
-#ifdef CONFIG_ARMV8_SWITCH_TO_EL1 - armv8_switch_to_el2((u64)images->ft_addr, 0, 0, 0, - (u64)switch_to_el1, ES_TO_AARCH64); +#ifdef CONFIG_ARMV8_MULTIENTRY + int armv8_switch_to_el1 = -1; #else - if ((IH_ARCH_DEFAULT == IH_ARCH_ARM64) && - (images->os.arch == IH_ARCH_ARM)) - armv8_switch_to_el2(0, (u64)gd->bd->bi_arch_number, - (u64)images->ft_addr, 0, - (u64)images->ep, - ES_TO_AARCH32); - else - armv8_switch_to_el2((u64)images->ft_addr, 0, 0, 0, - images->ep, - ES_TO_AARCH64); + int armv8_switch_to_el1 = env_get_yesno("armv8_switch_to_el1"); #endif +#ifdef CONFIG_ARMV8_SWITCH_TO_EL1 + if (armv8_switch_to_el1 == -1) { + armv8_switch_to_el1 = 1; + } +#endif + if (armv8_switch_to_el1 == 1) { + armv8_switch_to_el2((u64)images->ft_addr, 0, 0, 0, + (u64)switch_to_el1, ES_TO_AARCH64); + } else { + if ((IH_ARCH_DEFAULT == IH_ARCH_ARM64) && + (images->os.arch == IH_ARCH_ARM)) + armv8_switch_to_el2(0, + (u64)gd->bd->bi_arch_number, + (u64)images->ft_addr, 0, + (u64)images->ep, + ES_TO_AARCH32); + else + armv8_switch_to_el2((u64)images->ft_addr, + 0, 0, 0, + images->ep, + ES_TO_AARCH64); + } } #else unsigned long machid = gd->bd->bi_arch_number;