From patchwork Tue Jan 11 13:06:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 12709855 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 2969CC433F5 for ; Tue, 11 Jan 2022 13:09:54 +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=7Kz1t2upLF/ILNdyoKWx4gpFUE1875RM/CAQjQO9aes=; b=a5vbhEXIMAKxe7 kB5M5S2mgj7PS/xLpJzFSlyW2WLiJ7aYu12NNMUThAOesp4JJqeXp573SoLVR+g7xiUAK+JmdwfT0 84Q5OxQgYoGM5OGkH/dyWZzriUUBtXgMGetXFNovOG4BYkjkx1ikStv+PPVHkisk73cwA2cf+0VQV OvqgaCvolzcnds05VLp3cWAvnReAfJPe6gPWjyMcTKsDKf/ie3gfuNoTTVJ3f9Od8r+vzq/0Cva7N znqKNVJyVlWHcEWulD0Yae4RKw+U8D4Yv9QGU5HOpRsU46BxzWd3vfEAfTaTg2yLPk51a83WJgBR9 JTt4qr3WzIvcmwoPAoQQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7Gt4-00GIqu-2t; Tue, 11 Jan 2022 13:08:30 +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 1n7Grq-00GIEU-JN for linux-arm-kernel@lists.infradead.org; Tue, 11 Jan 2022 13:07:16 +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 2DBB2106F; Tue, 11 Jan 2022 05:07:14 -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 62F2B3F774; Tue, 11 Jan 2022 05:07:13 -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, Wei.Chen@arm.com Subject: [bootwrapper PATCH 06/13] aarch64: initialize SCTLR_ELx for the boot-wrapper Date: Tue, 11 Jan 2022 13:06:46 +0000 Message-Id: <20220111130653.2331827-7-mark.rutland@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220111130653.2331827-1-mark.rutland@arm.com> References: <20220111130653.2331827-1-mark.rutland@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220111_050714_748669_71883C88 X-CRM114-Status: GOOD ( 12.37 ) 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: , 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 top 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..f0edd2a 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 (1 << 29 | 1 << 28 | 1 << 23 | 1 << 22 | \ + 1 << 18 | 1 << 16 | 1 << 11 | 1 << 5 | 1 << 4) + +#define SCTLR_EL2_RES1 (1 << 29 | 1 << 28 | 1 << 23 | 1 << 22 | \ + 1 << 18 | 1 << 16 | 1 << 11 | 1 << 5 | 1 << 4) + +#define SCTLR_EL1_RES1 (1 << 29 | 1 << 28 | 1 << 23 | 1 << 22 | \ + 1 << 11 | 1 << 8 | 1 << 7 | 1 << 4) + +#define HCR_EL2_RES1 (1 << 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 */