From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ACF6CC07E96 for ; Wed, 14 Jul 2021 02:21:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9691861361 for ; Wed, 14 Jul 2021 02:21:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237616AbhGNCYX (ORCPT ); Tue, 13 Jul 2021 22:24:23 -0400 Received: from foss.arm.com ([217.140.110.172]:55810 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237611AbhGNCYX (ORCPT ); Tue, 13 Jul 2021 22:24:23 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 00DA91FB; Tue, 13 Jul 2021 19:21:32 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.65.222]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8FA033F7D8; Tue, 13 Jul 2021 19:21:28 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: akpm@linux-foundation.org, suzuki.poulose@arm.com, mark.rutland@arm.com, will@kernel.org, catalin.marinas@arm.com, maz@kernel.org, james.morse@arm.com, steven.price@arm.com, Anshuman Khandual Subject: [RFC 07/10] arm64/mm: Detect and enable FEAT_LPA2 Date: Wed, 14 Jul 2021 07:51:28 +0530 Message-Id: <1626229291-6569-8-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1626229291-6569-1-git-send-email-anshuman.khandual@arm.com> References: <1626229291-6569-1-git-send-email-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Detect FEAT_LPA2 implementation early enough during boot when requested via CONFIG_ARM64_PA_BITS_52_LPA2 and remember in a variable arm64_lpa2_enabled. This variable could then be used to turn on TCR_EL1.TCR_DS effecting the 52 bits PA range or fall back to default 48 bits PA range if FEAT_LPA2 feature was requested but found not to be implemented. Signed-off-by: Anshuman Khandual --- arch/arm64/include/asm/memory.h | 1 + arch/arm64/kernel/head.S | 15 +++++++++++++++ arch/arm64/mm/mmu.c | 3 +++ arch/arm64/mm/proc.S | 9 +++++++++ 4 files changed, 28 insertions(+) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 824a365..d0ca002 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -178,6 +178,7 @@ #include extern u64 vabits_actual; +extern u64 arm64_lpa2_enabled; extern s64 memstart_addr; /* PHYS_OFFSET - the physical address of the start of memory. */ diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 6444147..9cf79ea 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -94,6 +94,21 @@ SYM_CODE_START(primary_entry) adrp x23, __PHYS_OFFSET and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0 bl set_cpu_boot_mode_flag + +#ifdef CONFIG_ARM64_PA_BITS_52_LPA2 + mrs x10, ID_AA64MMFR0_EL1 + ubfx x10, x10, #ID_AA64MMFR0_TGRAN_SHIFT, 4 + cmp x10, #ID_AA64MMFR0_TGRAN_LPA2 + b.ne 1f + + mov x10, #1 + adr_l x11, arm64_lpa2_enabled + str x10, [x11] + dmb sy + dc ivac, x11 +1: +#endif /* CONFIG_ARM64_PA_BITS_52_LPA2 */ + bl __create_page_tables /* * The following calls CPU setup code, see arch/arm64/mm/proc.S for diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index d745865..00b7595 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -48,6 +48,9 @@ u64 idmap_ptrs_per_pgd = PTRS_PER_PGD; u64 __section(".mmuoff.data.write") vabits_actual; EXPORT_SYMBOL(vabits_actual); +u64 __section(".mmuoff.data.write") arm64_lpa2_enabled; +EXPORT_SYMBOL(arm64_lpa2_enabled); + u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 1ae0c2b..672880c 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -423,6 +423,15 @@ SYM_FUNC_START(__cpu_setup) TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \ TCR_TBI0 | TCR_A1 | TCR_KASAN_SW_FLAGS +#ifdef CONFIG_ARM64_PA_BITS_52_LPA2 + ldr_l x10, arm64_lpa2_enabled + cmp x10, #1 + b.ne 1f + mov_q x10, TCR_DS + orr tcr, tcr, x10 +1: +#endif /* CONFIG_ARM64_PA_BITS_52_LPA2 */ + #ifdef CONFIG_ARM64_MTE /* * Update MAIR_EL1, GCR_EL1 and TFSR*_EL1 if MTE is supported -- 2.7.4