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2017-12-17xtensa: add support for KASANMax Filippov1-0/+6
Cover kernel addresses above 0x90000000 by the shadow map. Enable HAVE_ARCH_KASAN when MMU is enabled. Provide kasan_early_init that fills shadow map with writable copies of kasan_zero_page. Call kasan_early_init right after mmu initialization in the setup_arch. Provide kasan_init that allocates proper shadow map pages from the memblock and puts these pages into the shadow map for addresses from VMALLOC area to the end of KSEG. Call kasan_init right after memblock initialization. Don't use KASAN for the boot code, MMU and KASAN initialization and page fault handler. Make kernel stack size 4 times larger when KASAN is enabled to avoid stack overflows. GCC 7.3, 8 or newer is required to build the xtensa kernel with KASAN. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-12-17xtensa: move fixmap and kmap just above the KSEGMax Filippov1-36/+36
The virtual address space between the page table and the VMALLOC region is big enough to host KASAN shadow map and there's enough space between the VMALLOC area and KSEG for the fixmap and kmap. Move fixmap and kmap to the gap between VMALLOC area and KSEG, just above the KSEG. Reorder entries in the kernel memory layout printing code. Drop duplicate PGTABLE_START definition, use XCHAL_PAGE_TABLE_VADDR instead. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-06-22of: update ePAPR references to point to Devicetree SpecificationFrank Rowand1-3/+3
The Devicetree Specification has superseded the ePAPR as the base specification for bindings. Update files in Documentation to reference the new document. First reference to ePAPR in Documentation/devicetree/bindings/arm/cci.txt is generic, remove it. Some files are not updated because there is no hypervisor chapter in the Devicetree Specification: Documentation/devicetree/bindings/powerpc/fsl/msi-pic.txt Documenation/virtual/kvm/api.txt Documenation/virtual/kvm/ppc-pv.txt Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2016-07-24xtensa: cleanup MMU setup and kernel layout macrosMax Filippov1-27/+22
Make kernel load address explicit, independent of the selected MMU configuration and configurable from Kconfig. Do not restrict it to the first 512MB of the physical address space. Cleanup kernel memory layout macros: - rename VECBASE_RESET_VADDR to VECBASE_VADDR, XC_VADDR to VECTOR_VADDR; - drop VIRTUAL_MEMORY_ADDRESS and LOAD_MEMORY_ADDRESS; - introduce PHYS_OFFSET and use it in __va and __pa definitions; - synchronize MMU/noMMU vectors, drop unused NMI vector; - replace hardcoded vectors offset of 0x3000 with Kconfig symbol. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-07-24xtensa: add alternative kernel memory layoutsMax Filippov1-0/+124
MMUv3 is able to support low memory bigger than 128MB. Implement 256MB and 512MB KSEG layouts: - add Kconfig selector for KSEG layout; - add KSEG base address, size and alignment definitions to arch/xtensa/include/asm/kmem_layout.h; - use new definitions in TLB initialization; - add build time memory map consistency checks. See Documentation/xtensa/mmu.txt for the details of new memory layouts. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2014-01-15xtensa: remap io area defined in device treeBaruch Siach1-0/+18
Use the simple-bus node to discover the io area, and remap the cached and bypass io ranges. The parent-bus-address value of the first triplet in the "ranges" property is used. This value is rounded down to the nearest 256MB boundary. The length of the io area is fixed at 256MB; the "ranges" property length value is ignored. Other limitations: (1) only the first simple-bus node is considered, and (2) only the first triplet of the "ranges" property is considered. See ePAPR 1.1 §6.5 for the simple-bus node description, and §2.3.8 for the "ranges" property description. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2014-01-15xtensa: fix ATOMCTL register documentationBaruch Siach1-1/+1
Make the WT entry match table 4-52 of the Xtensa ISA RM (RD-2012.5). Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2013-05-09xtensa: document MMUv3 setup sequenceMax Filippov1-0/+46
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net>
2012-12-19xtensa: initialize atomctl SRMax Filippov1-0/+44
In order to use S32C1I instruction on cores with ATOMCTL SR the register must be properly initialized. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net>