[PATCH v2 20/21] arm64: VHE: Add support for running Linux in EL2 mode
From: Suzuki.Poulose@arm.com (Suzuki K. Poulose)
Date: 2016-01-26 14:05:06
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On 25/01/16 15:53, Marc Zyngier wrote:
With ARMv8.1 VHE, the architecture is able to (almost) transparently run the kernel at EL2, despite being written for EL1. This patch takes care of the "almost" part, mostly preventing the kernel from dropping from EL2 to EL1, and setting up the HYP configuration.
quoted hunk ↗ jump to hunk
#ifdef CONFIG_COMPAT@@ -521,6 +542,15 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems /* Stage-2 translation */ msr vttbr_el2, xzr + cbz x2, install_el2_stub
Though it is apparent, may be its worth adding a comment here that we don't drop to EL1 here ?
+ + setup_vtcr x4, x5 + + mov w20, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 + isb + ret
+ +install_el2_stub:
And a comment here mentioning, install the hyp stub and drops to EL1 ?
/* Hypervisor stub */ adrp x0, __hyp_stub_vectors add x0, x0, #:lo12:__hyp_stub_vectors
Cheers Suzuki