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2014-04-08Merge tag 'arm64-upstream' of ↵Linus Torvalds1-2/+8
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull second set of arm64 updates from Catalin Marinas: "A second pull request for this merging window, mainly with fixes and docs clarification: - Documentation clarification on CPU topology and booting requirements - Additional cache flushing during boot (needed in the presence of external caches or under virtualisation) - DMA range invalidation fix for non cache line aligned buffers - Build failure fix with !COMPAT - Kconfig update for STRICT_DEVMEM" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Fix DMA range invalidation for cache line unaligned buffers arm64: Add missing Kconfig for CONFIG_STRICT_DEVMEM arm64: fix !CONFIG_COMPAT build failures Revert "arm64: virt: ensure visibility of __boot_cpu_mode" arm64: Relax the kernel cache requirements for boot arm64: Update the TCR_EL1 translation granule definitions for 16K pages ARM: topology: Make it clear that all CPUs need to be described
2014-04-07arm64: add early_ioremap supportMark Salter1-2/+2
Add support for early IO or memory mappings which are needed before the normal ioremap() is usable. This also adds fixmap support for permanent fixed mappings such as that used by the earlyprintk device register region. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Will Deacon <will.deacon@arm.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>
2014-04-05arm64: Relax the kernel cache requirements for bootCatalin Marinas1-2/+8
With system caches for the host OS or architected caches for guest OS we cannot easily guarantee that there are no dirty or stale cache lines for the areas of memory written by the kernel during boot with the MMU off (therefore non-cacheable accesses). This patch adds the necessary cache maintenance during boot and relaxes the booting requirements. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-26arm64: Extend the PCI I/O space to 16MBCatalin Marinas1-6/+10
The patch moves the PCI I/O space (currently at 64K) before the earlyprintk mapping and extends it to 16MB. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-11-05arm64: Use 42-bit address space with 64K pagesCatalin Marinas1-1/+26
This patch expands the VA_BITS to 42 when the 64K page configuration is enabled allowing 2TB kernel linear mapping. Linux still uses 2 levels of page tables in this configuration with pgd now being a full page. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2013-10-24Docs: arm64: booting: clarify boot requirementsMark Rutland1-14/+31
There are a few points in the arm64 booting document which are unclear (such as the initial state of secondary CPUs), and/or have not been documented (PSCI is a supported mechanism for booting secondary CPUs). This patch amends the arm64 boot document to better express the (existing) requirements, and to describe PSCI as a supported booting mechanism. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Fu Wei <tekkamanninja@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-24arm64: Fix memory layout typoCatalin Marinas1-1/+1
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-09-20arm64: documentation: tighten up tagged pointer documentationWill Deacon1-7/+7
Commit d50240a5f6ce ("arm64: mm: permit use of tagged pointers at EL0") added support for tagged pointers in userspace, but the corresponding update to Documentation/ contained some imprecise statements. This patch fixes up some minor ambiguities in the text, hopefully making it more clear about exactly what the kernel expects from user virtual addresses. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-09-05Documentation/arm64: clarify requirements for DTB placementMark Salter1-3/+3
The current description of DTB placement requirements does not quite match the kernel code in head.S: __vet_fdt and __create_page_tables. This patch tweaks the text to match the actual requirements placed on it by the code. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-09-03arm64: mm: permit use of tagged pointers at EL0Will Deacon1-0/+34
TCR.TBI0 can be used to cause hardware address translation to ignore the top byte of userspace virtual addresses. Whilst not especially useful in standard C programs, this can be used by JITs to `tag' pointers with various pieces of metadata. This patch enables this bit for AArch64 Linux, and adds a new file to Documentation/arm64/ which describes some potential caveats when using tagged virtual addresses. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-08-22arm64: Expand arm64 image headerRoy Franz1-3/+13
Expand the arm64 image header to allow for co-existance with PE/COFF header required by the EFI stub. The PE/COFF format requires the "MZ" header to be at offset 0, and the offset to the PE/COFF header to be at offset 0x3c. The image header is expanded to allow 2 instructions at the beginning to accommodate a benign intruction at offset 0 that includes the "MZ" header, a magic number, and the offset to the PE/COFF header. Signed-off-by: Roy Franz <roy.franz@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-06-12arm64: KVM: document kernel object mappings in HYPMarc Zyngier1-0/+7
HYP mode has access to some of the kernel pages. Document the memory mapping and the offset between kernel VA and HYP VA. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-22arm64: Add simple earlyprintk supportCatalin Marinas1-0/+2
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>
2012-11-29Documentation: Fixes a word in Documentation/arm64/memory.txtTekkaman Ninja1-1/+1
Fixes a term in Documentation/arm64/memory.txt The modification is based on Catalin Marinas <catalin.marinas@arm.com>'s suggestion: "memory" in "ffffffc000000000 ffffffffffffffff 256GB memory" should be treated as "kernel logical memory map". Signed-off-by: Fu Wei <tekkamanninja@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-10-23arm64: Move PCI_IOBASE closer to MODULES_VADDRCatalin Marinas1-6/+6
This is to reuse the same pmd table that is sparsely populated with the modules space. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-09-17arm64: MMU definitionsCatalin Marinas1-0/+73
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>
2012-09-17arm64: Kernel booting and initialisationCatalin Marinas1-0/+152
The patch adds the kernel booting and the initial setup code. Documentation/arm64/booting.txt describes the booting protocol on the AArch64 Linux kernel. This is subject to change following the work on boot standardisation, ACPI. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>