On 06/20/2016 04:07 PM, Alexander Graf wrote:
Some boards decided not to run ATF or other secure firmware in EL3, so they instead run U-Boot there. The uEFI spec doesn't know what EL3 is though - it only knows about EL2 and EL1. So if we see that we're running in EL3, let's get into EL2 to make payloads happy.
Signed-off-by: Alexander Graf agraf@suse.de
arch/arm/include/asm/armv8/mmu.h | 19 ++++++++++++------- cmd/bootefi.c | 11 +++++++++++ 2 files changed, 23 insertions(+), 7 deletions(-)
diff --git a/arch/arm/include/asm/armv8/mmu.h b/arch/arm/include/asm/armv8/mmu.h index 0d08ed3..876a2b2 100644 --- a/arch/arm/include/asm/armv8/mmu.h +++ b/arch/arm/include/asm/armv8/mmu.h @@ -116,19 +116,24 @@ static inline void set_ttbr_tcr_mair(int el, u64 table, u64 tcr, u64 attr) { asm volatile("dsb sy");
- if (el == 1) {
- switch (el) {
- case 1: asm volatile("msr ttbr0_el1, %0" : : "r" (table) : "memory"); asm volatile("msr tcr_el1, %0" : : "r" (tcr) : "memory"); asm volatile("msr mair_el1, %0" : : "r" (attr) : "memory");
- } else if (el == 2) {
asm volatile("msr ttbr0_el2, %0" : : "r" (table) : "memory");asm volatile("msr tcr_el2, %0" : : "r" (tcr) : "memory");asm volatile("msr mair_el2, %0" : : "r" (attr) : "memory");- } else if (el == 3) {
break;- case 3: asm volatile("msr ttbr0_el3, %0" : : "r" (table) : "memory"); asm volatile("msr tcr_el3, %0" : : "r" (tcr) : "memory"); asm volatile("msr mair_el3, %0" : : "r" (attr) : "memory");
- } else {
/* We may switch to EL2 later, so set those too; fall through */- case 2:
asm volatile("msr ttbr0_el2, %0" : : "r" (table) : "memory");asm volatile("msr tcr_el2, %0" : : "r" (tcr) : "memory");asm volatile("msr mair_el2, %0" : : "r" (attr) : "memory");break;
This may be problematic. If we use secure memory for EL3, the MMU tables have to be within the secure memory. But EL2 will not be able to access it. I believe you have verified this patch set actually work. I am curious how it work.
York