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=-13.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 63336C4727E for ; Tue, 6 Oct 2020 09:51:05 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1A91B20639 for ; Tue, 6 Oct 2020 09:51:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="GGYQjK0/"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="OyZvsOBP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A91B20639 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3PimPmzkB7duEozwWJ2imdSr9vtExxkCZjWHPUZRVCk=; b=GGYQjK0/ocsELfpqeCj7RWpHaH JAuJlDQDjOx8C44pE69qlptI1mX8L8AitoT+rpl9brfO40aw5yCAPsIfv1qBa+YjsQhRSjeFGC+f4 5+yEzcaHqj4iws4uczqQMP8gikdOCQfFGOc/V+3/g6Up9Iv2N5vvFiJUh3LUIhZ1ZzMFUXRq9pmui 7JLBElUV+dng9bz4nC3Afb72sv64KUV657lgKHbxZC38HDask0MipFI9UTWMjTHcQvwusdutj/ReH /Gl++b/HDClr+fZYFl5ilt1EYFSZkos/OV6aMYXsbLLdWnl4nvAgGCnqKx9oRTvp0QN1FgT4nSkf2 qoN+KFaA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPjbB-0000Sx-Dl; Tue, 06 Oct 2020 09:49:33 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPjb7-0000S1-Jy for linux-arm-kernel@lists.infradead.org; Tue, 06 Oct 2020 09:49:31 +0000 Received: from e123331-lin.nice.arm.com (lfbn-nic-1-188-42.w2-15.abo.wanadoo.fr [2.15.37.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E2FDA20853; Tue, 6 Oct 2020 09:49:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601977768; bh=oJMT+P6M4tWW/eFz1GvMdIEFd7ld/LGGaAyvZm8E2PI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OyZvsOBPHIjKD5Ypl7KOyAp//fTN0z5MoOr/OydQy0SvFG5Pol8O1gRuJyov44mBw nFl5HpGbCZW5x7wOtLH+4xuvF4H0r9HerNC29RwKNO4QUCxS9fW4i19Ke24hVzez5F X4D2inMgd4pCdc/PGXQUbMpya9LirSs1UuMnB6Hw= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 2/2] ARM: move device tree mapping out of linear region Date: Tue, 6 Oct 2020 11:49:18 +0200 Message-Id: <20201006094918.9819-3-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201006094918.9819-1-ardb@kernel.org> References: <20201006094918.9819-1-ardb@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201006_054929_849172_4F794A00 X-CRM114-Status: GOOD ( 23.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Florian Fainelli , Nicolas Pitre , Linus Walleij , Russell King , Rob Herring , Ard Biesheuvel MIME-Version: 1.0 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 On ARM, setting up the linear region is tricky, given the constraints around placement and alignment of the memblocks, and how the kernel itself as well as the DT are placed in physical memory. Let's simplify matters a bit, by moving the device tree mapping to the top of the address space, right below the fixmap region, and create a read-only mapping for it that is independent of the size of the linear region, and how it is organized. Signed-off-by: Ard Biesheuvel --- arch/arm/include/asm/memory.h | 5 +++++ arch/arm/kernel/head.S | 5 ++--- arch/arm/kernel/setup.c | 11 ++++++++--- arch/arm/mm/init.c | 1 - arch/arm/mm/mmu.c | 20 ++++++++++++++------ arch/arm/mm/pv-fixup-asm.S | 4 ++-- 6 files changed, 31 insertions(+), 15 deletions(-) diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index 99035b5891ef..ad9dcf4f751d 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -67,6 +67,10 @@ */ #define XIP_VIRT_ADDR(physaddr) (MODULES_VADDR + ((physaddr) & 0x000fffff)) +#define FDT_FIXED_BASE UL(0xff800000) +#define FDT_FIXED_SIZE (2 * PMD_SIZE) +#define FDT_VIRT_ADDR(physaddr) ((void *)(FDT_FIXED_BASE | (physaddr) % PMD_SIZE)) + #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) /* * Allow 16MB-aligned ioremap pages @@ -107,6 +111,7 @@ extern unsigned long vectors_base; #define MODULES_VADDR PAGE_OFFSET #define XIP_VIRT_ADDR(physaddr) (physaddr) +#define FDT_VIRT_ADDR(physaddr) (physaddr) #endif /* !CONFIG_MMU */ diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index f8904227e7fd..9b18d8c66129 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -275,9 +275,8 @@ __create_page_tables: */ mov r0, r2, lsr #SECTION_SHIFT movs r0, r0, lsl #SECTION_SHIFT - subne r3, r0, r8 - addne r3, r3, #PAGE_OFFSET - addne r3, r4, r3, lsr #(SECTION_SHIFT - PMD_ORDER) + ldrne r3, =FDT_FIXED_BASE >> (SECTION_SHIFT - PMD_ORDER) + addne r3, r3, r4 orrne r6, r7, r0 strne r6, [r3], #1 << PMD_ORDER addne r6, r6, #1 << SECTION_SHIFT diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 0ea0172d0c6d..bdba280a569d 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -89,7 +90,6 @@ unsigned int cacheid __read_mostly; EXPORT_SYMBOL(cacheid); unsigned int __atags_pointer __initdata; -void *atags_vaddr __initdata; unsigned int system_rev; EXPORT_SYMBOL(system_rev); @@ -1077,13 +1077,18 @@ void __init hyp_mode_check(void) void __init setup_arch(char **cmdline_p) { const struct machine_desc *mdesc = NULL; + void *atags_vaddr; if (__atags_pointer) - atags_vaddr = phys_to_virt(__atags_pointer); + atags_vaddr = FDT_VIRT_ADDR(__atags_pointer); setup_processor(); - if (atags_vaddr) + if (atags_vaddr) { mdesc = setup_machine_fdt(atags_vaddr); + if (mdesc) + memblock_reserve(__atags_pointer, + fdt_totalsize(atags_vaddr)); + } if (!mdesc) mdesc = setup_machine_tags(atags_vaddr, __machine_arch_type); if (!mdesc) { diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 000c1b48e973..652a87bd065c 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -223,7 +223,6 @@ void __init arm_memblock_init(const struct machine_desc *mdesc) if (mdesc->reserve) mdesc->reserve(); - early_init_fdt_reserve_self(); early_init_fdt_scan_reserved_mem(); /* reserve memory for DMA contiguous allocations */ diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 0665a0dbd040..59fe24eb23c6 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -40,6 +40,8 @@ #include "mm.h" #include "tcm.h" +extern unsigned long __atags_pointer; + /* * empty_zero_page is a special page that is used for * zero-initialized data and COW. @@ -947,7 +949,7 @@ static void __init create_mapping(struct map_desc *md) return; } - if ((md->type == MT_DEVICE || md->type == MT_ROM) && + if (md->type == MT_DEVICE && md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START && (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) { pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n", @@ -1343,6 +1345,15 @@ static void __init devicemaps_init(const struct machine_desc *mdesc) for (addr = VMALLOC_START; addr < (FIXADDR_TOP & PMD_MASK); addr += PMD_SIZE) pmd_clear(pmd_off_k(addr)); + if (__atags_pointer) { + /* create a read-only mapping of the device tree or ATAGS data */ + map.pfn = __phys_to_pfn(__atags_pointer & SECTION_MASK); + map.virtual = FDT_FIXED_BASE; + map.length = FDT_FIXED_SIZE; + map.type = MT_ROM; + create_mapping(&map); + } + /* * Map the kernel if it is XIP. * It is always first in the modulearea. @@ -1503,8 +1514,7 @@ static void __init map_lowmem(void) } #ifdef CONFIG_ARM_PV_FIXUP -extern void *atags_vaddr; -typedef void pgtables_remap(long long offset, unsigned long pgd, void *bdata); +typedef void pgtables_remap(long long offset, unsigned long pgd); pgtables_remap lpae_pgtables_remap_asm; /* @@ -1517,7 +1527,6 @@ static void __init early_paging_init(const struct machine_desc *mdesc) unsigned long pa_pgd; unsigned int cr, ttbcr; long long offset; - void *boot_data; if (!mdesc->pv_fixup) return; @@ -1534,7 +1543,6 @@ static void __init early_paging_init(const struct machine_desc *mdesc) */ lpae_pgtables_remap = (pgtables_remap *)(unsigned long)__pa(lpae_pgtables_remap_asm); pa_pgd = __pa(swapper_pg_dir); - boot_data = atags_vaddr; barrier(); pr_info("Switching physical address space to 0x%08llx\n", @@ -1570,7 +1578,7 @@ static void __init early_paging_init(const struct machine_desc *mdesc) * needs to be assembly. It's fairly simple, as we're using the * temporary tables setup by the initial assembly code. */ - lpae_pgtables_remap(offset, pa_pgd, boot_data); + lpae_pgtables_remap(offset, pa_pgd); /* Re-enable the caches and cacheable TLB walks */ asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr)); diff --git a/arch/arm/mm/pv-fixup-asm.S b/arch/arm/mm/pv-fixup-asm.S index 8eade0416739..5c5e1952000a 100644 --- a/arch/arm/mm/pv-fixup-asm.S +++ b/arch/arm/mm/pv-fixup-asm.S @@ -39,8 +39,8 @@ ENTRY(lpae_pgtables_remap_asm) /* Update level 2 entries for the boot data */ add r7, r2, #0x1000 - add r7, r7, r3, lsr #SECTION_SHIFT - L2_ORDER - bic r7, r7, #(1 << L2_ORDER) - 1 + movw r3, #FDT_FIXED_BASE >> (SECTION_SHIFT - L2_ORDER) + add r7, r7, r3 ldrd r4, r5, [r7] adds r4, r4, r0 adc r5, r5, r1 -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel