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path: root/arch/arm/mach-tegra/arm64-mmu.c
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2019-01-24arm64: zynqmp: Move SoC sources to mach-zynqmpMichal Simek
Similar changes was done for Zynq in past and this patch just follow this pattern to separate cpu code from SoC code. Move arch/arm/cpu/armv8/zynqmp/* -> arch/arm/mach-zynqmp/* And also fix references to these files. Based on "ARM: zynq: move SoC sources to mach-zynq" (sha1: 0107f2403669f764ab726d0d404e35bb9447bbcc) Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2018-05-07SPDX: Convert all of our single license tags to Linux Kernel styleTom Rini
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
2018-01-12ARM: Tegra186: don't map memory not in RAM banksStephen Warren
Tegra186 currently restricts its DRAM usage to entries in the /memory node in the DTB passed to it. However, the MMU configuration always maps the entire first 2GB of RAM. This could allow the CPU to speculatively access RAM that isn't part of the in-use banks. This patch switches to runtime construction of the table that's used to construct the MMU translation tables, and thus prevents access to RAM that's not part of a valid bank. Note: This patch is intended to prevent access to RAM regions which U-Boot does not need to access, with the primary purpose of avoiding theoretical speculative access to physical regions for which the HW will throw errors (e.g. carve-outs that the CPU has no permission to access at a bus level, bad ECC pages, etc.). In particular, this patch is not deliberately related to the speculation-related security issues that were recently announced. The apparent similarity is a coincidence. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-10-10ARM: tegra: reduce DRAM size mapped into MMU on ARM64Stephen Warren
ARM CPUs can architecturally (speculatively) prefetch completely arbitrary normal memory locations, as defined by the current translation tables. The current MMU configuration for 64-bit Tegras maps an extremely large range of addresses as DRAM, well beyond the actual physical maximum DRAM window, even though U-Boot only needs access to the first 2GB of DRAM; the Tegra port of U-Boot deliberately limits itself to 2GB of RAM since some HW modules on at least some 64-bit Tegra SoCs can only access a 32-bit physical address space. This change reduces the amount of RAM mapped via the MMU to disallow the CPU from ever speculatively accessing RAM that U-Boot will definitely not access. This avoids the possibility of the HW raising SError due to accesses to always-invalid physical addresses. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Tom Warren <twarren@nvidia.com>
2016-07-15armv8: mmu: Add support of non-identical mappingYork Sun
Introduce virtual and physical addresses in the mapping table. This change have no impact on existing boards because they all use idential mapping. Signed-off-by: York Sun <york.sun@nxp.com>
2016-03-15tegra: Replace home grown mmu code with generic table approachAlexander Graf
Now that we have nice table driven page table creating code that gives us everything we need, move to that. Signed-off-by: Alexander Graf <agraf@suse.de>
2015-11-10ARM: tegra: add custom MMU setup on ARMv8Stephen Warren
This sets up a fine-grained page table, which is a requirement for noncached_init() to operate correctly. MMU setup code currently exists in a number of places: - A version in the core ARMv8 support code that sets up page tables that use very large block sizes that CONFIG_SYS_NONCACHED_MEMORY doesn't support. - Enhanced versions for fsl-lsch3 and zynmq that set up finer grained page tables. Ideally, rather than duplicating the MMU setup code yet again this patch would instead consolidate all the different routines into the core ARMv8 code so that it supported all use-cases. However, this will require significant effort since there appear to be a number of discrepancies[1] between different versions of the code, and between the defines/values by some copies of the MMU setup code use and the architectural MMU documentation. Some reverse engineering will be required to determine the intent of the current code. [1] For example, in the core ARMv8 MMU setup code, three defines named TCR_EL[123]_IPS_BITS exist, but only one of them sets the IPS field and the others set a different field (T1SZ) in the page tables. As far as I can tell so far, there should be no need to set different values per exception level nor to modify the T1SZ field at all, since TTBR1 shouldn't be enabled anyway. Another example is inconsistent values for *_VA_BITS between the current core ARMv8 MMU setup code and the various SoC- specific MMU setup code. Another example is that asm/armv8/mmu.h's value for SECTION_SHIFT doesn't match asm/system.h's MMU_SECTION_SHIFT; research is needed to determine which code relies on which of those values and why, and whether fixing the incorrect value will cause any regression. Signed-off-by: Stephen Warren <swarren@nvidia.com>