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=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 DEBBDC4363A for ; Thu, 29 Oct 2020 00:55:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A11A20724 for ; Thu, 29 Oct 2020 00:55:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603932910; bh=+zNrzC58AmTmQdxW/VhUY1K98MXF8eaS6GBLj+PjHAM=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=GeQmTl2zcPCYgEcHsdckNYiKxTeMm7gkMtEv2LkQSvt8R9QhR095wjcoAS5tCXFIL DQ87FJEro/MTe0zOmJsfY/rpj4JB5fCZL3W645WG2iJE2sAi/xnrEztmuT3UUEQQz0 XqJekmWHjd+ZcPR839X4OkziobDFVNO4QcdjNPs4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731726AbgJ1WSB (ORCPT ); Wed, 28 Oct 2020 18:18:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:60520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731731AbgJ1WRo (ORCPT ); Wed, 28 Oct 2020 18:17:44 -0400 Received: from mail-oi1-f179.google.com (mail-oi1-f179.google.com [209.85.167.179]) (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 A19EC24695 for ; Wed, 28 Oct 2020 09:24:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603877096; bh=+zNrzC58AmTmQdxW/VhUY1K98MXF8eaS6GBLj+PjHAM=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=cUCOU0U1fgOwaUpVqDxwZZ0dkw5Jr0ufeRAb0VVaIfUEy0nUouPm86dAtkEpr81YR c/lAe+sexDugUAaFIF2AAy3SLc3uN8SiEzD9JExXmqJIRV4yqLmYWeX3mPGPkraHGB hKfk4HK5gEPrUil3qF9GIkhBv118Ow/Bxi7YRvIY= Received: by mail-oi1-f179.google.com with SMTP id c72so4281423oig.9 for ; Wed, 28 Oct 2020 02:24:56 -0700 (PDT) X-Gm-Message-State: AOAM5304HsiakmZY8UUu0ohUmqVarUOHRBiuIjoWxoBKrK/RASXMxzdL U6giF95RZWrUWUSjnmn6F1qQL5a9c1be9h/lseI= X-Google-Smtp-Source: ABdhPJyyRAmDQMdwC7t6Fqk/Fg6hl0XopTLtmRvhfLrsi/q1dX6Oc8I/m/OT565jJ+lRTC/tLDANpYzSq8aGCRj2gls= X-Received: by 2002:aca:5c82:: with SMTP id q124mr4450009oib.33.1603877095700; Wed, 28 Oct 2020 02:24:55 -0700 (PDT) MIME-Version: 1.0 References: <20201007083944.27910-1-ardb@kernel.org> <20201007083944.27910-3-ardb@kernel.org> <920965b8-6f87-3f82-9fce-d3051fc543ca@samsung.com> In-Reply-To: From: Ard Biesheuvel Date: Wed, 28 Oct 2020 10:24:44 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 2/2] ARM: move device tree mapping out of linear region To: Marek Szyprowski Cc: Linux ARM , Linux Samsung SOC , Krzysztof Kozlowski , Florian Fainelli , Nicolas Pitre , Linus Walleij , Russell King , Rob Herring Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org On Wed, 28 Oct 2020 at 10:22, Ard Biesheuvel wrote: > > On Wed, 28 Oct 2020 at 10:19, Marek Szyprowski wrote: > > > > Hi, > > > > On 07.10.2020 10:39, Ard Biesheuvel wrote: > > > 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 between the end of the vmalloc region > > > and the start of the 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. > > > > > > Since this region was formerly used as a guard region, which will now be > > > populated fully on LPAE builds by this read-only mapping (which will > > > still be able to function as a guard region for stray writes), bump the > > > start of the [underutilized] fixmap region by 512 KB as well, to ensure > > > that there is always a proper guard region here. Doing so still leaves > > > ample room for the fixmap space, even with NR_CPUS set to its maximum > > > value of 32. > > > > > > Tested-by: Linus Walleij > > > Reviewed-by: Linus Walleij > > > Signed-off-by: Ard Biesheuvel > > > > This patch landed in linux-next 20201028 as commit 7a1be318f579 ("ARM: > > 9012/1: move device tree mapping out of linear region"). Sadly it broke > > booting almost all Samsung Exynos-based boards. The only one which > > booted, used an appended device tree. I can provide more information if > > needed, just let me know what to check. "Starting kernel ..." is the > > last message I see here. No output from earlycon. > > > > Thanks for the report. I will have a look later today. > > Do these platforms happen to have any static device mappings that may > collide with this mapping of the FDT? Also, could this be related to > device drivers making changes in memory to the FDT image? Because the > permanent mapping of the FDT is read-only now. > IOW, does using MT_MEMORY_RW instead of MT_ROM for the mapping make a difference? > > > > > --- > > > Documentation/arm/memory.rst | 7 ++++++- > > > arch/arm/include/asm/fixmap.h | 2 +- > > > 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 ++-- > > > 8 files changed, 38 insertions(+), 17 deletions(-) > > > > > > diff --git a/Documentation/arm/memory.rst b/Documentation/arm/memory.rst > > > index 0521b4ce5c96..34bb23c44a71 100644 > > > --- a/Documentation/arm/memory.rst > > > +++ b/Documentation/arm/memory.rst > > > @@ -45,9 +45,14 @@ fffe8000 fffeffff DTCM mapping area for platforms with > > > fffe0000 fffe7fff ITCM mapping area for platforms with > > > ITCM mounted inside the CPU. > > > > > > -ffc00000 ffefffff Fixmap mapping region. Addresses provided > > > +ffc80000 ffefffff Fixmap mapping region. Addresses provided > > > by fix_to_virt() will be located here. > > > > > > +ffc00000 ffc7ffff Guard region > > > + > > > +ff800000 ffbfffff Permanent, fixed read-only mapping of the > > > + firmware provided DT blob > > > + > > > fee00000 feffffff Mapping of PCI I/O space. This is a static > > > mapping within the vmalloc space. > > > > > > diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h > > > index fc56fc3e1931..9575b404019c 100644 > > > --- a/arch/arm/include/asm/fixmap.h > > > +++ b/arch/arm/include/asm/fixmap.h > > > @@ -2,7 +2,7 @@ > > > #ifndef _ASM_FIXMAP_H > > > #define _ASM_FIXMAP_H > > > > > > -#define FIXADDR_START 0xffc00000UL > > > +#define FIXADDR_START 0xffc80000UL > > > #define FIXADDR_END 0xfff00000UL > > > #define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) > > > > > > 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 58e56e23a19a..c08574cad748 100644 > > > --- a/arch/arm/kernel/setup.c > > > +++ b/arch/arm/kernel/setup.c > > > @@ -18,6 +18,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -90,7 +91,6 @@ 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); > > > @@ -1078,13 +1078,18 @@ 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..a7231d151c63 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 */ > > > + 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 > > > > Best regards > > -- > > Marek Szyprowski, PhD > > Samsung R&D Institute Poland > > 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=-10.0 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 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 DF1E2C4363A for ; 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Wed, 28 Oct 2020 02:24:55 -0700 (PDT) MIME-Version: 1.0 References: <20201007083944.27910-1-ardb@kernel.org> <20201007083944.27910-3-ardb@kernel.org> <920965b8-6f87-3f82-9fce-d3051fc543ca@samsung.com> In-Reply-To: From: Ard Biesheuvel Date: Wed, 28 Oct 2020 10:24:44 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 2/2] ARM: move device tree mapping out of linear region To: Marek Szyprowski X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201028_052457_979377_5F597118 X-CRM114-Status: GOOD ( 48.36 ) 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 , Krzysztof Kozlowski , Rob Herring , Linux Samsung SOC , Linux ARM 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 Wed, 28 Oct 2020 at 10:22, Ard Biesheuvel wrote: > > On Wed, 28 Oct 2020 at 10:19, Marek Szyprowski wrote: > > > > Hi, > > > > On 07.10.2020 10:39, Ard Biesheuvel wrote: > > > 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 between the end of the vmalloc region > > > and the start of the 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. > > > > > > Since this region was formerly used as a guard region, which will now be > > > populated fully on LPAE builds by this read-only mapping (which will > > > still be able to function as a guard region for stray writes), bump the > > > start of the [underutilized] fixmap region by 512 KB as well, to ensure > > > that there is always a proper guard region here. Doing so still leaves > > > ample room for the fixmap space, even with NR_CPUS set to its maximum > > > value of 32. > > > > > > Tested-by: Linus Walleij > > > Reviewed-by: Linus Walleij > > > Signed-off-by: Ard Biesheuvel > > > > This patch landed in linux-next 20201028 as commit 7a1be318f579 ("ARM: > > 9012/1: move device tree mapping out of linear region"). Sadly it broke > > booting almost all Samsung Exynos-based boards. The only one which > > booted, used an appended device tree. I can provide more information if > > needed, just let me know what to check. "Starting kernel ..." is the > > last message I see here. No output from earlycon. > > > > Thanks for the report. I will have a look later today. > > Do these platforms happen to have any static device mappings that may > collide with this mapping of the FDT? Also, could this be related to > device drivers making changes in memory to the FDT image? Because the > permanent mapping of the FDT is read-only now. > IOW, does using MT_MEMORY_RW instead of MT_ROM for the mapping make a difference? > > > > > --- > > > Documentation/arm/memory.rst | 7 ++++++- > > > arch/arm/include/asm/fixmap.h | 2 +- > > > 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 ++-- > > > 8 files changed, 38 insertions(+), 17 deletions(-) > > > > > > diff --git a/Documentation/arm/memory.rst b/Documentation/arm/memory.rst > > > index 0521b4ce5c96..34bb23c44a71 100644 > > > --- a/Documentation/arm/memory.rst > > > +++ b/Documentation/arm/memory.rst > > > @@ -45,9 +45,14 @@ fffe8000 fffeffff DTCM mapping area for platforms with > > > fffe0000 fffe7fff ITCM mapping area for platforms with > > > ITCM mounted inside the CPU. > > > > > > -ffc00000 ffefffff Fixmap mapping region. Addresses provided > > > +ffc80000 ffefffff Fixmap mapping region. Addresses provided > > > by fix_to_virt() will be located here. > > > > > > +ffc00000 ffc7ffff Guard region > > > + > > > +ff800000 ffbfffff Permanent, fixed read-only mapping of the > > > + firmware provided DT blob > > > + > > > fee00000 feffffff Mapping of PCI I/O space. This is a static > > > mapping within the vmalloc space. > > > > > > diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h > > > index fc56fc3e1931..9575b404019c 100644 > > > --- a/arch/arm/include/asm/fixmap.h > > > +++ b/arch/arm/include/asm/fixmap.h > > > @@ -2,7 +2,7 @@ > > > #ifndef _ASM_FIXMAP_H > > > #define _ASM_FIXMAP_H > > > > > > -#define FIXADDR_START 0xffc00000UL > > > +#define FIXADDR_START 0xffc80000UL > > > #define FIXADDR_END 0xfff00000UL > > > #define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) > > > > > > 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 58e56e23a19a..c08574cad748 100644 > > > --- a/arch/arm/kernel/setup.c > > > +++ b/arch/arm/kernel/setup.c > > > @@ -18,6 +18,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -90,7 +91,6 @@ 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); > > > @@ -1078,13 +1078,18 @@ 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..a7231d151c63 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 */ > > > + 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 > > > > Best regards > > -- > > Marek Szyprowski, PhD > > Samsung R&D Institute Poland > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel