diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S index 2a55373f49bf..0b1e4a93d67e 100644 --- a/arch/arm/kernel/hyp-stub.S +++ b/arch/arm/kernel/hyp-stub.S @@ -17,6 +17,7 @@ */ #include +#include #include #include #include @@ -159,6 +160,29 @@ ARM_BE8(orr r7, r7, #(1 << 25)) @ HSCTLR.EE bic r7, #1 @ Clear ENABLE mcr p15, 0, r7, c14, c3, 1 @ CNTV_CTL 1: +#endif + +#ifdef CONFIG_ARM_GIC_V3 + @ Check whether GICv3 system registers are available + mrc p15, 0, r7, c0, c1, 1 @ ID_PFR1 + ubfx r7, r7, #28, #4 + cmp r7, #1 + bne 2f + + @ Enable system register accesses + mrc p15, 4, r7, c12, c9, 5 @ ICC_HSRE + orr r7, r7, #(ICC_SRE_EL2_ENABLE | ICC_SRE_EL2_SRE) + mcr p15, 4, r7, c12, c9, 5 @ ICC_HSRE + isb + + @ SRE bit could be forced to 0 by firmware. + @ Check whether it sticks before accessing any other sysreg + mrc p15, 4, r7, c12, c9, 5 @ ICC_HSRE + tst r7, #ICC_SRE_EL2_SRE + beq 2f + mov r7, #0 + mcr p15, 4, r7, c12, c11, 0 @ ICH_HCR +2: #endif bx lr @ The boot CPU mode is left in r4.