aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm64/include/asm/mmu.h (follow)
AgeCommit message (Collapse)AuthorFilesLines
2019-08-23arm64: map FDT as RW for early_init_dt_scan()Hsin-Yi Wang1-1/+1
Currently in arm64, FDT is mapped to RO before it's passed to early_init_dt_scan(). However, there might be some codes (eg. commit "fdt: add support for rng-seed") that need to modify FDT during init. Map FDT to RO after early fixups are done. Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner1-12/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-21arm64: Remove asm/memblock.hWill Deacon1-0/+1
The arm64 asm/memblock.h header exists only to provide a function prototype for arm64_memblock_init(), which is called only from setup_arch(). Move the declaration into mmu.h, where it can live alongside other init functions such as paging_init() and bootmem_init() without the need for its own special header file. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-01-16arm64: kpti: Update arm64_kernel_use_ng_mappings() when forced onJames Morse1-1/+4
Since commit b89d82ef01b3 ("arm64: kpti: Avoid rewriting early page tables when KASLR is enabled"), a kernel built with CONFIG_RANDOMIZE_BASE can decide early whether to use non-global mappings by checking the kaslr_offset(). A kernel built without CONFIG_RANDOMIZE_BASE, instead checks the cpufeature static-key. This leaves a gap where CONFIG_RANDOMIZE_BASE was enabled, no kaslr seed was provided, but kpti was forced on using the cmdline option. When the decision is made late, kpti_install_ng_mappings() will re-write the page tables, but arm64_kernel_use_ng_mappings()'s value does not change as it only tests the cpufeature static-key if CONFIG_RANDOMIZE_BASE is disabled. This function influences PROT_DEFAULT via PTE_MAYBE_NG, and causes pgattr_change_is_safe() to catch nG->G transitions when the unchanged PROT_DEFAULT is used as part of PAGE_KERNEL_RO: [ 1.942255] alternatives: patching kernel code [ 1.998288] ------------[ cut here ]------------ [ 2.000693] kernel BUG at arch/arm64/mm/mmu.c:165! [ 2.019215] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 2.020257] Modules linked in: [ 2.020807] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc2 #51 [ 2.021917] Hardware name: linux,dummy-virt (DT) [ 2.022790] pstate: 40000005 (nZcv daif -PAN -UAO) [ 2.023742] pc : __create_pgd_mapping+0x508/0x6d0 [ 2.024671] lr : __create_pgd_mapping+0x500/0x6d0 [ 2.058059] Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____)) [ 2.059369] Call trace: [ 2.059845] __create_pgd_mapping+0x508/0x6d0 [ 2.060684] update_mapping_prot+0x48/0xd0 [ 2.061477] mark_linear_text_alias_ro+0xdc/0xe4 [ 2.070502] smp_cpus_done+0x90/0x98 [ 2.071216] smp_init+0x100/0x114 [ 2.071878] kernel_init_freeable+0xd4/0x220 [ 2.072750] kernel_init+0x10/0x100 [ 2.073455] ret_from_fork+0x10/0x18 [ 2.075414] ---[ end trace 3572f3a7782292de ]--- [ 2.076389] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b If arm64_kernel_unmapped_at_el0() is true, arm64_kernel_use_ng_mappings() should also be true. Signed-off-by: James Morse <james.morse@arm.com> CC: Ard Biesheuvel <ard.biesheuvel@linaro.org> CC: John Garry <john.garry@huawei.com> CC: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-01-10arm64: kpti: Avoid rewriting early page tables when KASLR is enabledWill Deacon1-0/+41
A side effect of commit c55191e96caa ("arm64: mm: apply r/o permissions of VM areas to its linear alias as well") is that the linear map is created with page granularity, which means that transitioning the early page table from global to non-global mappings when enabling kpti can take a significant amount of time during boot. Given that most CPU implementations do not require kpti, this mainly impacts KASLR builds where kpti is forcefully enabled. However, in these situations we know early on that non-global mappings are required and can avoid the use of global mappings from the beginning. The only gotcha is Cavium erratum #27456, which we must detect based on the MIDR value of the boot CPU. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reported-by: John Garry <john.garry@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-09-25arm64/mm: Separate boot-time page tables from swapper_pg_dirJun Yao1-0/+3
Since the address of swapper_pg_dir is fixed for a given kernel image, it is an attractive target for manipulation via an arbitrary write. To mitigate this we'd like to make it read-only by moving it into the rodata section. We require that swapper_pg_dir is at a fixed offset from tramp_pg_dir and reserved_ttbr0, so these will also need to move into rodata. However, swapper_pg_dir is allocated along with some transient page tables used for boot which we do not want to move into rodata. As a step towards this, this patch separates the boot-time page tables into a new init_pg_dir, and reduces swapper_pg_dir to the single page it needs to be. This allows us to retain the relationship between swapper_pg_dir, tramp_pg_dir, and swapper_pg_dir, while cleanly separating these from the boot-time page tables. The init_pg_dir holds all of the pgd/pud/pmd/pte levels needed during boot, and all of these levels will be freed when we switch to the swapper_pg_dir, which is initialized by the existing code in paging_init(). Since we start off on the init_pg_dir, we no longer need to allocate a transient page table in paging_init() in order to ensure that swapper_pg_dir isn't live while we initialize it. There should be no functional change as a result of this patch. Signed-off-by: Jun Yao <yaojun8558363@gmail.com> Reviewed-by: James Morse <james.morse@arm.com> [Mark: place init_pg_dir after BSS, fold mm changes, commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-03-19arm64: KVM: Allow mapping of vectors outside of the RAM regionMarc Zyngier1-1/+4
We're now ready to map our vectors in weird and wonderful locations. On enabling ARM64_HARDEN_EL2_VECTORS, a vector slot gets allocated if this hasn't been already done via ARM64_HARDEN_BRANCH_PREDICTOR and gets mapped outside of the normal RAM region, next to the idmap. That way, being able to obtain VBAR_EL2 doesn't reveal the mapping of the rest of the hypervisor code. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19arm64: Make BP hardening slot counter availableMarc Zyngier1-0/+3
We're about to need to allocate hardening slots from other parts of the kernel (in order to support ARM64_HARDEN_EL2_VECTORS). Turn the counter into an atomic_t and make it available to the rest of the kernel. Also add BP_HARDEN_EL2_SLOTS as the number of slots instead of the hardcoded 4... Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-01-14arm64: sdei: Add trampoline code for remapping the kernelJames Morse1-1/+2
When CONFIG_UNMAP_KERNEL_AT_EL0 is set the SDEI entry point and the rest of the kernel may be unmapped when we take an event. If this may be the case, use an entry trampoline that can switch to the kernel page tables. We can't use the provided PSTATE to determine whether to switch page tables as we may have interrupted the kernel's entry trampoline, (or a normal-priority event that interrupted the kernel's entry trampoline). Instead test for a user ASID in ttbr1_el1. Save a value in regs->addr_limit to indicate whether we need to restore the original ASID when returning from this event. This value is only used by do_page_fault(), which we don't call with the SDEI regs. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-08arm64: Add skeleton to harden the branch predictor against aliasing attacksWill Deacon1-0/+37
Aliasing attacks against CPU branch predictors can allow an attacker to redirect speculative control flow on some CPUs and potentially divulge information from one context to another. This patch adds initial skeleton code behind a new Kconfig option to enable implementation-specific mitigations against these attacks for CPUs that are affected. Co-developed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-11arm64: mm: Introduce TTBR_ASID_MASK for getting at the ASID in the TTBRWill Deacon1-0/+1
There are now a handful of open-coded masks to extract the ASID from a TTBR value, so introduce a TTBR_ASID_MASK and use that instead. Suggested-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Tested-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-11arm64: entry: Add fake CPU feature for unmapping the kernel at EL0Will Deacon1-1/+2
Allow explicit disabling of the entry trampoline on the kernel command line (kpti=off) by adding a fake CPU feature (ARM64_UNMAP_KERNEL_AT_EL0) that can be used to toggle the alternative sequences in our entry code and avoid use of the trampoline altogether if desired. This also allows us to make use of a static key in arm64_kernel_unmapped_at_el0(). Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Tested-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-11arm64: mm: Add arm64_kernel_unmapped_at_el0 helperWill Deacon1-0/+8
In order for code such as TLB invalidation to operate efficiently when the decision to map the kernel at EL0 is determined at runtime, this patch introduces a helper function, arm64_kernel_unmapped_at_el0, to determine whether or not the kernel is mapped whilst running in userspace. Currently, this just reports the value of CONFIG_UNMAP_KERNEL_AT_EL0, but will later be hooked up to a fake CPU capability using a static key. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Tested-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-11arm64: mm: Allocate ASIDs in pairsWill Deacon1-0/+1
In preparation for separate kernel/user ASIDs, allocate them in pairs for each mm_struct. The bottom bit distinguishes the two: if it is set, then the ASID will map only userspace. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Tested-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-22arm64: introduce separated bits for mm_context_t flagsYury Norov1-0/+2
Currently mm->context.flags field uses thread_info flags which is not the best idea for many reasons. For example, mm_context_t doesn't need most of thread_info flags. And it would be difficult to add new mm-related flag if needed because it may easily interfere with TIF ones. To deal with it, the new MMCF_AARCH32 flag is introduced for mm_context_t->flags, where MMCF prefix stands for mm_context_t flags. Also, mm_context_t flag doesn't require atomicity and ordering of the access, so using set/clear_bit() is replaced with simple masks. Signed-off-by: Yury Norov <ynorov@caviumnetworks.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-23arm64: alternatives: apply boot time fixups via the linear mappingArd Biesheuvel1-0/+1
One important rule of thumb when desiging a secure software system is that memory should never be writable and executable at the same time. We mostly adhere to this rule in the kernel, except at boot time, when regions may be mapped RWX until after we are done applying alternatives or making other one-off changes. For the alternative patching, we can improve the situation by applying the fixups via the linear mapping, which is never mapped with executable permissions. So map the linear alias of .text with RW- permissions initially, and remove the write permissions as soon as alternative patching has completed. Reviewed-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-07arm64: introduce mm context flag to keep 32 bit task informationPratyush Anand1-0/+1
We need to decide in some cases like uprobe instruction analysis that whether the current mm context belongs to a 32 bit task or 64 bit. This patch has introduced an unsigned flag variable in mm_context_t. Currently, we set and clear TIF_32BIT depending on the condition that whether an elf binary load sets personality for 32 bit or 64 bit respectively. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-07arm64: mm: replace 'block_mappings_allowed' with 'page_mappings_only'Ard Biesheuvel1-1/+1
In preparation of adding support for contiguous PTE and PMD mappings, let's replace 'block_mappings_allowed' with 'page_mappings_only', which will be a more accurate description of the nature of the setting once we add such contiguous mappings into the mix. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01arm64: mm: add param to force create_pgd_mapping() to use page mappingsArd Biesheuvel1-1/+1
Add a bool parameter 'allow_block_mappings' to create_pgd_mapping() and the various helper functions that it descends into, to give the caller control over whether block entries may be used to create the mapping. The UEFI runtime mapping routines will use this to avoid creating block entries that would need to split up into page entries when applying the permissions listed in the Memory Attributes firmware table. This also replaces the block_mappings_allowed() helper function that was added for DEBUG_PAGEALLOC functionality, but the resulting code is functionally equivalent (given that debug_page_alloc does not operate on EFI page table entries anyway) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-04-15arm64: Move unflatten_device_tree() call earlier.David Daney1-0/+1
In order to extract NUMA information from the device tree, we need to have the tree in its unflattened form. Move the call to bootmem_init() in the tail of paging_init() into setup_arch, and adjust header files so that its declaration is visible. Move the unflatten_device_tree() call between the calls to paging_init() and bootmem_init(). Follow on patches add NUMA handling to bootmem_init(). Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-07arm64: mm: rewrite ASID allocator and MM context-switching codeWill Deacon1-7/+8
Our current switch_mm implementation suffers from a number of problems: (1) The ASID allocator relies on IPIs to synchronise the CPUs on a rollover event (2) Because of (1), we cannot allocate ASIDs with interrupts disabled and therefore make use of a TIF_SWITCH_MM flag to postpone the actual switch to finish_arch_post_lock_switch (3) We run context switch with a reserved (invalid) TTBR0 value, even though the ASID and pgd are updated atomically (4) We take a global spinlock (cpu_asid_lock) during context-switch (5) We use h/w broadcast TLB operations when they are not required (e.g. in flush_context) This patch addresses these problems by rewriting the ASID algorithm to match the bitmap-based arch/arm/ implementation more closely. This in turn allows us to remove much of the complications surrounding switch_mm, including the ugly thread flag. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-27arm64: remove dead codeMark Salter1-1/+0
Commit 68234df4ea79 ("arm64: kill flush_cache_all()") removed soft_reset() from the kernel. This was the only caller of setup_mm_for_reboot(), so remove that also. Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-06-02arm64: use fixmap region for permanent FDT mappingArd Biesheuvel1-0/+1
Currently, the FDT blob needs to be in the same 512 MB region as the kernel, so that it can be mapped into the kernel virtual memory space very early on using a minimal set of statically allocated translation tables. Now that we have early fixmap support, we can relax this restriction, by moving the permanent FDT mapping to the fixmap region instead. This way, the FDT blob may be anywhere in memory. This also moves the vetting of the FDT to mmu.c, since the early init code in head.S does not handle mapping of the FDT anymore. At the same time, fix up some comments in head.S that have gone stale. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-12arm64/efi: remove idmap manipulations from UEFI codeArd Biesheuvel1-2/+0
Now that we have moved the call to SetVirtualAddressMap() to the stub, UEFI has no use for the ID map, so we can drop the code that installs ID mappings for UEFI memory regions. Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12arm64/mm: add create_pgd_mapping() to create private page tablesArd Biesheuvel1-0/+3
For UEFI, we need to install the memory mappings used for Runtime Services in a dedicated set of page tables. Add create_pgd_mapping(), which allows us to allocate and install those page table entries early. Reviewed-by: Will Deacon <will.deacon@arm.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-06-05Merge branch 'arm64-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into nextLinus Torvalds1-0/+2
Pull ARM64 EFI update from Peter Anvin: "By agreement with the ARM64 EFI maintainers, we have agreed to make -tip the upstream for all EFI patches. That is why this patchset comes from me :) This patchset enables EFI stub support for ARM64, like we already have on x86" * 'arm64-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arm64: efi: only attempt efi map setup if booting via EFI efi/arm64: ignore dtb= when UEFI SecureBoot is enabled doc: arm64: add description of EFI stub support arm64: efi: add EFI stub doc: arm: add UEFI support documentation arm64: add EFI runtime services efi: Add shared FDT related functions for ARM/ARM64 arm64: Add function to create identity mappings efi: add helper function to get UEFI params from FDT doc: efi-stub.txt updates for ARM lib: add fdt_empty_tree.c
2014-04-30arm64: Add function to create identity mappingsMark Salter1-0/+2
At boot time, before switching to a virtual UEFI memory map, firmware expects UEFI memory and IO regions to be identity mapped whenever kernel makes runtime services calls. The existing early boot code creates an identity map of kernel text/data but this is not sufficient for UEFI. This patch adds a create_id_mapping() function which reuses the core code of the existing create_mapping(). Signed-off-by: Mark Salter <msalter@redhat.com> [ Fixed error message formatting (%pa). ] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-25arm64: initialize spinlock for init_mm's contextLeo Yan1-0/+3
ARM64 has defined the spinlock for init_mm's context, so need initialize the spinlock structure; otherwise during the suspend flow it will dump the info for spinlock's bad magic warning as below: [ 39.084394] Disabling non-boot CPUs ... [ 39.092871] BUG: spinlock bad magic on CPU#1, swapper/1/0 [ 39.092896] lock: init_mm+0x338/0x3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 [ 39.092907] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G O 3.10.33 #125 [ 39.092912] Call trace: [ 39.092927] [<ffffffc000087e64>] dump_backtrace+0x0/0x16c [ 39.092934] [<ffffffc000087fe0>] show_stack+0x10/0x1c [ 39.092947] [<ffffffc000765334>] dump_stack+0x1c/0x28 [ 39.092953] [<ffffffc0007653b8>] spin_dump+0x78/0x88 [ 39.092960] [<ffffffc0007653ec>] spin_bug+0x24/0x34 [ 39.092971] [<ffffffc000300a28>] do_raw_spin_lock+0x98/0x17c [ 39.092979] [<ffffffc00076cf08>] _raw_spin_lock_irqsave+0x4c/0x60 [ 39.092990] [<ffffffc000094044>] set_mm_context+0x1c/0x6c [ 39.092996] [<ffffffc0000941c8>] __new_context+0x94/0x10c [ 39.093007] [<ffffffc0000d63d4>] idle_task_exit+0x104/0x1b0 [ 39.093014] [<ffffffc00008d91c>] cpu_die+0x14/0x74 [ 39.093021] [<ffffffc000084f74>] arch_cpu_idle_dead+0x8/0x14 [ 39.093030] [<ffffffc0000e7f18>] cpu_startup_entry+0x1ec/0x258 [ 39.093036] [<ffffffc00008d810>] secondary_start_kernel+0x114/0x124 Signed-off-by: Leo Yan <leoy@marvell.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-04-07arm64: initialize pgprot info earlier in bootMark Salter1-0/+1
Presently, paging_init() calls init_mem_pgprot() to initialize pgprot values used by macros such as PAGE_KERNEL, PAGE_KERNEL_EXEC, etc. The new fixmap and early_ioremap support also needs to use these macros before paging_init() is called. This patch moves the init_mem_pgprot() call out of paging_init() and into setup_arch() so that pgprot_default gets initialized in time for fixmap and early_ioremap. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-22arm64: Add simple earlyprintk supportCatalin Marinas1-0/+1
This patch adds support for "earlyprintk=" parameter on the kernel command line. The format is: earlyprintk=<name>[,<addr>][,<options>] where <name> is the name of the (UART) device, e.g. "pl011", <addr> is the I/O address. The <options> aren't currently used. The mapping of the earlyprintk device is done very early during kernel boot and there are restrictions on which functions it can call. A special early_io_map() function is added which creates the mapping from the pre-defined EARLY_IOBASE to the device I/O address passed via the kernel parameter. The pgd entry corresponding to EARLY_IOBASE is pre-populated in head.S during kernel boot. Only PL011 is currently supported and it is assumed that the interface is already initialised by the boot loader before the kernel is started. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-09-17arm64: MMU definitionsCatalin Marinas1-0/+30
The virtual memory layout is described in Documentation/arm64/memory.txt. This patch adds the MMU definitions for the 4KB and 64KB translation table configurations. The SECTION_SIZE is 2MB with 4KB page and 512MB with 64KB page configuration. PHYS_OFFSET is calculated at run-time and stored in a variable (no run-time code patching at this stage). On the current implementation, both user and kernel address spaces are 512G (39-bit) each with a maximum of 256G for the RAM linear mapping. Linux uses 3 levels of translation tables with the 4K page configuration and 2 levels with the 64K configuration. Extending the memory space beyond 39-bit with the 4K pages or 42-bit with 64K pages requires an additional level of translation tables. The SPARSEMEM configuration is global to all AArch64 platforms and allows for 1GB sections with SPARSEMEM_VMEMMAP enabled by default. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>