From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B596522EE4 for ; Mon, 13 Nov 2023 17:43:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pmRBNJGa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 155D5C433D9; Mon, 13 Nov 2023 17:43:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699897425; bh=mDtW4Z8A35acA1VEGJf/ya9n7T6SEZP2HzCfuJMDHcI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pmRBNJGaEz3mol0snFfXEoLkMTBJswLqCDKrxZtBJUiEv2rACqT8qmOEN8mN1i1ED DYVTpxNgudYABtA1xDC4lP8HiPRqlOykBnvANzBqPhn/7UtJtPRsqSJpaIHT0CQXs7 BV8FCmBH4TVkGc/dDbNRC2JtnVVJAEZvT40Y+4h/vBb9Uptcj0bmd7jV06cYx8yauE sMiraiHjkpkyjWO3Bh0JvjnD9la3AAILFGTrb3y1Xe4OaIgzPmguNoTkmHYuYSIjQt YMOHragIFmf7ZkJ25PN+nAvut5WLGXqnBV69U8bEU9quJO4ZrRZfOceVOip7G+9U8o ITHrFmZBmeB1A== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1r2ayN-00CkQ4-68; Mon, 13 Nov 2023 17:43:43 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Catalin Marinas , Will Deacon , Mark Rutland , James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH 07/12] arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is non-zero Date: Mon, 13 Nov 2023 17:42:39 +0000 Message-Id: <20231113174244.3026520-8-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231113174244.3026520-1-maz@kernel.org> References: <20231113174244.3026520-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false For CPUs that have ID_AA64MMFR4_EL1.E2H0 as non-zero, it is important to avoid the boot path that sets HCR_EL2.E2H=0. Fortunately, we already have this path to cope with fruity CPUs. Tweak init_el2 to look at ID_AA64MMFR4_EL1.E2H0 first. Signed-off-by: Marc Zyngier --- arch/arm64/kernel/head.S | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 7b236994f0e1..5853540f7809 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -584,25 +584,34 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL) mov_q x1, INIT_SCTLR_EL1_MMU_OFF /* - * Fruity CPUs seem to have HCR_EL2.E2H set to RES1, - * making it impossible to start in nVHE mode. Is that - * compliant with the architecture? Absolutely not! + * Compliant CPUs advertise their VHE-onlyness with + * ID_AA64MMFR4_EL1.E2H0=0b111x. HCR_EL2.E2H can be + * RES1 in that case. + * + * Fruity CPUs seem to have HCR_EL2.E2H set to RES1, but + * don't advertise it (they predate this relaxation). */ + mrs_s x0, SYS_ID_AA64MMFR4_EL1 + ubfx x0, x0, #ID_AA64MMFR4_EL1_E2H0_SHIFT, #ID_AA64MMFR4_EL1_E2H0_WIDTH + and x0, x0, #0b1110 + cmp x0, #0b1110 + b.eq 1f + mrs x0, hcr_el2 and x0, x0, #HCR_E2H - cbz x0, 1f - + cbz x0, 2f +1: /* Set a sane SCTLR_EL1, the VHE way */ pre_disable_mmu_workaround msr_s SYS_SCTLR_EL12, x1 mov x2, #BOOT_CPU_FLAG_E2H - b 2f + b 3f -1: +2: pre_disable_mmu_workaround msr sctlr_el1, x1 mov x2, xzr -2: +3: __init_el2_nvhe_prepare_eret mov w0, #BOOT_CPU_MODE_EL2 -- 2.39.2