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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2067BC433EF for ; Fri, 14 Jan 2022 10:59:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=gGqZljt2ZJ2B0QO/b9QcTTEahgDvNn/tlM2XSot4LT4=; b=oTQ2KWBHZBX+As C3fZC9CA97FR93RUXumnJ4CBVaGTrizXrtJs1xzl6vmFkUYNDiXbiGSxiMmm/5qTHZmH4vff+I9fR m3mlOiCSr/rj6BpBUdI8wrFgYrIF7pOgqUeNjbxHwFb9PN3rJVVwIc9kLQuUvZP3wtTSIF53+9RTQ Ji/SoQqkbDbVTCllMXFiMTI+6bfAtOBI0x0MekkqTO7dzHOrfs5dT8we2rULaxlt3vER94LCJ15L5 KkfAyoWCaQJMY4xjFvf4Ld99CcsENd4MnZE7tRzqBjp+aneiP848AET6EORMGmJNBmN67WNzSQgcp BTT0VNZUsDcQ9i0flDNw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n8KHu-008oi1-Te; Fri, 14 Jan 2022 10:58:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n8KGf-008o5v-Ck for linux-arm-kernel@lists.infradead.org; Fri, 14 Jan 2022 10:57:15 +0000 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 A61C711B3; Fri, 14 Jan 2022 02:57:12 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A09CA3F766; Fri, 14 Jan 2022 02:57:11 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: andre.przywara@arm.com, Jaxson.Han@arm.com, mark.rutland@arm.com, robin.murphy@arm.com, vladimir.murzin@arm.com, Wei.Chen@arm.com Subject: [bootwrapper PATCH v2 06/13] aarch64: initialize SCTLR_ELx for the boot-wrapper Date: Fri, 14 Jan 2022 10:56:46 +0000 Message-Id: <20220114105653.3003399-7-mark.rutland@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220114105653.3003399-1-mark.rutland@arm.com> References: <20220114105653.3003399-1-mark.rutland@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220114_025713_558741_355B9ED0 X-CRM114-Status: GOOD ( 12.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The SCTLR_ELx registers contain fields which are UNKNOWN or IMPLEMENTATION DEFINED out of reset. This includes SCTLR_ELx.EE, which defines the endianness of memory accesses (e.g. reads from literal pools). Due to this, portions of boot-wrapper code are not guaranteed to work correctly. Rework the startup code to explicitly initialize SCTLR_ELx for the exception level the boot-wrapper was entered at. When entered at EL2 it's necessary to first initialise HCR_EL2.E2H as this affects the RESx behaviour of bits in SCTLR_EL2, and also aliases SCTLR_EL1 to SCTLR_EL2, which would break the initialization performed in jump_kernel. As we plan to eventually support the highest implemented EL being any of EL3/EL2/EL1, code is added to handle all of these exception levels, even though we do not currently support starting at EL1. We'll initialize other registers in subsequent patches. Signed-off-by: Mark Rutland --- arch/aarch64/boot.S | 74 +++++++++++++++++++++++++++------- arch/aarch64/include/asm/cpu.h | 27 ++++++++++++- 2 files changed, 85 insertions(+), 16 deletions(-) diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S index 900b9f8..45a0367 100644 --- a/arch/aarch64/boot.S +++ b/arch/aarch64/boot.S @@ -26,26 +26,26 @@ * PSCI is not supported when entered in this exception level. */ ASM_FUNC(_start) - cpuid x0, x1 - bl find_logical_id - cmp x0, #MPIDR_INVALID - beq err_invalid_id - bl setup_stack - - /* - * EL3 initialisation - */ mrs x0, CurrentEL cmp x0, #CURRENTEL_EL3 - b.eq 1f + b.eq reset_at_el3 + cmp x0, #CURRENTEL_EL2 + b.eq reset_at_el2 + cmp x0, #CURRENTEL_EL1 + b.eq reset_at_el1 - mov w0, #1 - ldr x1, =flag_no_el3 - str w0, [x1] + /* Booting at EL0 is not supported */ + b . - b start_no_el3 + /* + * EL3 initialisation + */ +reset_at_el3: + mov_64 x0, SCTLR_EL3_RESET + msr sctlr_el3, x0 + isb -1: mov x0, #0x30 // RES1 + mov x0, #0x30 // RES1 orr x0, x0, #(1 << 0) // Non-secure EL1 orr x0, x0, #(1 << 8) // HVC enable @@ -135,10 +135,54 @@ ASM_FUNC(_start) ldr x0, =COUNTER_FREQ msr cntfrq_el0, x0 + cpuid x0, x1 + bl find_logical_id + cmp x0, #MPIDR_INVALID + b.eq err_invalid_id + bl setup_stack + bl gic_secure_init b start_el3 + /* + * EL2 initialization + */ +reset_at_el2: + // Ensure E2H is not in use + mov_64 x0, HCR_EL2_RESET + msr hcr_el2, x0 + isb + + mov_64 x0, SCTLR_EL2_RESET + msr sctlr_el2, x0 + isb + + b reset_no_el3 + + /* + * EL1 initialization + */ +reset_at_el1: + mov_64 x0, SCTLR_EL1_RESET + msr sctlr_el1, x0 + isb + + b reset_no_el3 + +reset_no_el3: + cpuid x0, x1 + bl find_logical_id + cmp x0, #MPIDR_INVALID + b.eq err_invalid_id + bl setup_stack + + mov w0, #1 + ldr x1, =flag_no_el3 + str w0, [x1] + + b start_no_el3 + err_invalid_id: b . diff --git a/arch/aarch64/include/asm/cpu.h b/arch/aarch64/include/asm/cpu.h index 1053414..1e9141a 100644 --- a/arch/aarch64/include/asm/cpu.h +++ b/arch/aarch64/include/asm/cpu.h @@ -14,6 +14,32 @@ #define MPIDR_ID_BITS 0xff00ffffff #define CURRENTEL_EL3 (3 << 2) +#define CURRENTEL_EL2 (2 << 2) +#define CURRENTEL_EL1 (1 << 2) + +/* + * RES1 bit definitions definitions as of ARM DDI 0487G.b + * + * These includes bits which are RES1 in some configurations. + */ +#define SCTLR_EL3_RES1 (BIT(29) | BIT(28) | BIT(23) | BIT(22) | \ + BIT(18) | BIT(16) | BIT(11) | BIT(5) | BIT(4)) + +#define SCTLR_EL2_RES1 (BIT(29) | BIT(28) | BIT(23) | BIT(22) | \ + BIT(18) | BIT(16) | BIT(11) | BIT(5) | BIT(4)) + +#define SCTLR_EL1_RES1 (BIT(29) | BIT(28) | BIT(23) | BIT(22) | \ + BIT(11) | BIT(8) | BIT(7) | BIT(4)) + +#define HCR_EL2_RES1 (BIT(1)) + +/* + * Initial register values required for the boot-wrapper to run out-of-reset. + */ +#define SCTLR_EL3_RESET SCTLR_EL3_RES1 +#define SCTLR_EL2_RESET SCTLR_EL2_RES1 +#define SCTLR_EL1_RESET SCTLR_EL1_RES1 +#define HCR_EL2_RESET HCR_EL2_RES1 #define ID_AA64PFR0_EL1_GIC BITS(27, 24) @@ -43,7 +69,6 @@ #define ZCR_EL3_LEN_MASK 0x1ff #define SCTLR_EL1_CP15BEN (1 << 5) -#define SCTLR_EL1_RES1 (3 << 28 | 3 << 22 | 1 << 11) #ifdef KERNEL_32 /* 32-bit kernel decompressor uses CP15 barriers */ -- 2.30.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel