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2023-05-29ARM: mm: Make virt_to_pfn() a static inlineLinus Walleij
Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. Doing this is a bit intrusive: virt_to_pfn() requires PHYS_PFN_OFFSET and PAGE_SHIFT to be defined, and this is defined in <asm/page.h>, so this must be included *before* <asm/memory.h>. The use of macros were obscuring the unclear inclusion order here, as the macros would eventually be resolved, but a static inline like this cannot be compiled with unresolved macros. The naive solution to include <asm/page.h> at the top of <asm/memory.h> does not work, because <asm/memory.h> sometimes includes <asm/page.h> at the end of itself, which would create a confusing inclusion loop. So instead, take the approach to always unconditionally include <asm/page.h> at the end of <asm/memory.h> arch/arm uses <asm/memory.h> explicitly in a lot of places, however it turns out that if we just unconditionally include <asm/memory.h> into <asm/page.h> and switch all inclusions of <asm/memory.h> to <asm/page.h> instead, we enforce the right order and <asm/memory.h> will always have access to the definitions. Put an inclusion guard in place making it impossible to include <asm/memory.h> explicitly. Link: https://lore.kernel.org/linux-mm/20220701160004.2ffff4e5ab59a55499f4c736@linux-foundation.org/ Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-12-17ARM: 9160/1: NOMMU: Reload __secondary_data after PROCINFO_INITFUNCVladimir Murzin
__secondary_data used to reside in r7 around call to PROCINFO_INITFUNC. After commit 95731b8ee63e ("ARM: 9059/1: cache-v7: get rid of mini-stack") r7 is used as a scratch register, so we have to reload __secondary_data before we setup the stack pointer. Fixes: 95731b8ee63e ("ARM: 9059/1: cache-v7: get rid of mini-stack") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-09-27ARM: smp: Pass task to secondary_start_kernelKeith Packard
This avoids needing to compute the task pointer in this function, which will no longer be possible once we move thread_info off the stack. Signed-off-by: Keith Packard <keithpac@amazon.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
2019-10-10ARM: 8914/1: NOMMU: Fix exc_ret for XIPVladimir Murzin
It was reported that 72cd4064fcca "NOMMU: Toggle only bits in EXC_RETURN we are really care of" breaks NOMMU+XIP combination. It happens because saved EXC_RETURN gets overwritten when data section is relocated. The fix is to propagate EXC_RETURN via register and let relocation code to commit that value into memory. Fixes: 72cd4064fcca ("ARM: 8830/1: NOMMU: Toggle only bits in EXC_RETURN we are really care of") Reported-by: afzal mohammed <afzal.mohd.ma@gmail.com> Tested-by: afzal mohammed <afzal.mohd.ma@gmail.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-23ARM: 8856/1: NOMMU: Fix CCR register faulty initialization when MPU is disabledTigran Tadevosyan
When CONFIG_ARM_MPU is not defined, the base address of v7M SCB register is not initialized with correct value. This prevents enabling I/D caches when the L1 cache poilcy is applied in kernel. Fixes: 3c24121039c9da14692eb48f6e39565b28c0f3cf ("ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init") Signed-off-by: Tigran Tadevosyan <tigran.tadevosyan@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-26ARM: 8849/1: NOMMU: Fix encodings for PMSAv8's PRBAR4/PRLAR4Vladimir Murzin
To access PRBARn, where n is referenced as a binary number: MRC p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0] ; Read PRBARn into Rt MCR p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0] ; Write Rt into PRBARn To access PRLARn, where n is referenced as a binary number: MRC p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0]+1 ; Read PRLARn into Rt MCR p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0]+1 ; Write Rt into PRLARn For PR{B,L}AR4, n is 4, n[0] is 0, n[3:1] is 2, while current encoding done with n[0] set to 1 which is wrong. Use proper encoding instead. Fixes: 046835b4aa22b9ab6aa0bb274e3b71047c4b887d ("ARM: 8757/1: NOMMU: Support PMSAv8 MPU") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-13Merge branches 'fixes', 'misc' and 'spectre' into for-linusRussell King
Conflicts: arch/arm/include/asm/uaccess.h Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-07-30ARM: 8784/1: NOMMU: Allow enter in Hyp modeVladimir Murzin
ARMv8R adds support for virtualisation extension (with some deviation from v8A). With this patch hyp-unaware boot code can offload to kernel setting up HYP stuff in a sane state. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-07-11ARM: 8775/1: NOMMU: Use instr_sync instead of plain isb in common codeVladimir Murzin
Greg reported that commit 3c24121039c9d ("ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init") is causing breakage for the old Versatile platform in no-MMU mode (with out-of-tree patches): AS arch/arm/kernel/head-nommu.o arch/arm/kernel/head-nommu.S: Assembler messages: arch/arm/kernel/head-nommu.S:180: Error: selected processor does not support `isb' in ARM mode scripts/Makefile.build:417: recipe for target 'arch/arm/kernel/head-nommu.o' failed make[2]: *** [arch/arm/kernel/head-nommu.o] Error 1 Makefile:1034: recipe for target 'arch/arm/kernel' failed make[1]: *** [arch/arm/kernel] Error 2 Since the code is common for all NOMMU builds usage of the isb was a bad idea (please, note that isb also used in MPU related code which is fine because MPU has dependency on CPU_V7/CPU_V7M), instead use more robust instr_sync assembler macro. Fixes: 3c24121039c9 ("ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init") Reported-by: Greg Ungerer <gerg@kernel.org> Tested-by: Greg Ungerer <gerg@kernel.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-19ARM: 8757/1: NOMMU: Support PMSAv8 MPUVladimir Murzin
ARMv8R/M architecture defines new memory protection scheme - PMSAv8 which is not compatible with PMSAv7. Key differences to PMSAv7 are: - Region geometry is defined by base and limit addresses - Addresses need to be either 32 or 64 byte aligned - No region priority due to overlapping regions are not allowed - It is unified, i.e. no distinction between data/instruction regions - Memory attributes are controlled via MAIR This patch implements support for PMSAv8 MPU defined by ARMv8R/M architecture. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-19ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_initVladimir Murzin
This patch postpone MPU activation till __after_proc_init (which is placed in .text section) rather than doing it in __setup_mpu. It allows us ignore used-only-once .head.text section while programming PMSAv8 MPU (for PMSAv7 it stays covered anyway). Tested-by: Szemz? András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-19ARM: 8755/1: NOMMU: Reorganise __setup_mpuVladimir Murzin
Currently, we have mixed code placement between .head.text and .text depends on configuration we are building: _text M R(UP) R(SMP) ====================================================== __setup_mpu __HEAD __HEAD text __after_proc_init __HEAD __HEAD text __mmap_switched text text text We are going to support another variant of MPU which is different to PMSAv7 in sense overlapping MPU regions are not allowed, so this patch makes boundaries between these sections precise and consistent: _text M R(UP) R(SMP) ====================================================== __setup_mpu __HEAD __HEAD __HEAD __after_proc_init text text text __mmap_switched text text text Additionally, it paves a path to postpone MPU activation till __after_proc_init where we do set SCTLR anyway and can return directly to __mmap_switched. Tested-by: Szemz? András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-19ARM: 8754/1: NOMMU: Move PMSAv7 MPU under it's own namespaceVladimir Murzin
We are going to support different MPU which programming model is not compatible to PMSAv7, so move PMSAv7 MPU under it's own namespace. Tested-by: Szemz? András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-10-23ARM: 8713/1: NOMMU: Support MPU in XIP configurationVladimir Murzin
Currently, there is assumption in early MPU setup code that kernel image is located in RAM, which is obviously not true for XIP. To run code from ROM we need to make sure that it is covered by MPU. However, due to we allocate regions (semi-)dynamically we can run into issue of trimming region we are running from in case ROM spawns several MPU regions. To help deal with that we enforce minimum alignments for start end end of XIP address space as 1MB and 128Kb correspondingly. Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-10-23ARM: 8711/1: V7M: Add support for MPU to M-classVladimir Murzin
This patch makes it possible to use MPU with v7M cores. Tested-by: Szemző András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-10-23ARM: 8708/1: NOMMU: Rework MPU to be mostly done in CVladimir Murzin
Currently, there are several issues with how MPU is setup: 1. We won't boot if MPU is missing 2. We won't boot if use XIP 3. Further extension of MPU setup requires asm skills The 1st point can be relaxed, so we can continue with boot CPU even if MPU is missed and fail boot for secondaries only. To address the 2nd point we could create region covering CONFIG_XIP_PHYS_ADDR - _end and that might work for the first stage of MPU enable, but due to MPU's alignment requirement we could cover too much, IOW we need more flexibility in how we're partitioning memory regions... and it'd be hardly possible to archive because of the 3rd point. This patch is trying to address 1st and 3rd issues and paves the path for 2nd and further improvements. The most visible change introduced with this patch is that we start using mpu_rgn_info array (as it was supposed?), so change in MPU setup done by boot CPU is recorded there and feed to secondaries. It allows us to keep minimal region setup for boot CPU and do the rest in C. Since we start programming MPU regions in C evaluation of MPU constrains (number of regions supported and minimal region order) can be done once, which in turn open possibility to free-up "probe" region early. Tested-by: Szemző András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-02-28ARM: 8649/2: nommu: remove Hivecs configuration is asmAfzal Mohammed
Now that exception based address is handled dynamically for processors with CP15, remove Hivecs configuration in assembly. Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-09-06ARM: 8607/1: V7M: Wire up caches for V7M processors with cache support.Jonathan Austin
This patch does the plumbing required to invoke the V7M cache code added in earlier patches in this series, although there is no users for that yet. In order to honour the I/D cache disable config options, this patch changes the mechanism by which the CCR is set on boot, to be more like V7A/R. Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Tested-by: Andras Szemzo <sza@esh.hu> Tested-by: Joachim Eastwood <manabian@gmail.com> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-05-05ARM: 8572/1: nommu: change memory reserve for the vectorsJean-Philippe Brucker
Commit 19accfd3 (ARM: move vector stubs) moved the vector stubs in an additional page above the base vector one. This change wasn't taken into account by the nommu memreserve. This patch ensures that the kernel won't overwrite any vector stub on nommu. [changed the MPU side too] Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-12ARM: 8383/1: nommu: avoid deprecated source register on movStefan Agner
In Thumb2 mode, the stack register r13 is deprecated if the destination register is the program counter (r15). Similar to head.S, head-nommu.S uses r13 to store the return address used after configuring the CPU's CP15 register. However, since we do not enable a MMU, there will be no address switch and it is possible to use branch with link instruction to call __after_proc_init. Avoid using r13 completely by using bl to call __after_proc_init and get rid of __secondary_switched. Beside removing unnecessary complexity, this also fixes a compiler warning when compiling a !MMU kernel: Warning: Use of r13 as a source register is deprecated when r15 is the destination register. Tested-?by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-12Merge branch 'bsym' into for-nextRussell King
Conflicts: arch/arm/kernel/head.S
2015-06-01ARM: redo TTBR setup code for LPAERussell King
Re-engineer the LPAE TTBR setup code. Rather than passing some shifted address in order to fit in a CPU register, pass either a full physical address (in the case of r4, r5 for TTBR0) or a PFN (for TTBR1). This removes the ARCH_PGD_SHIFT hack, and the last dangerous user of cpu_set_ttbr() in the secondary CPU startup code path (which was there to re-set TTBR1 to the appropriate high physical address space on Keystone2.) Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-08ARM: replace BSYM() with badr assembly macroRussell King
BSYM() was invented to allow us to work around a problem with the assembler, where local symbols resolved by the assembler for the 'adr' instruction did not take account of their ISA. Since we don't want BSYM() used elsewhere, replace BSYM() with a new macro 'badr', which is like the 'adr' pseudo-op, but with the BSYM() mechanics integrated into it. This ensures that the BSYM()-ification is only used in conjunction with 'adr'. Acked-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-21ARM: Fix nommu bootingRussell King
Commit bf35706f3d09 ("ARM: 8314/1: replace PROCINFO embedded branch with relative offset") broke booting on nommu platforms as it didn't update the nommu boot code. This patch fixes that oversight. Fixes: bf35706f3d09 ("ARM: 8314/1: replace PROCINFO embedded branch with relative offset") Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+Russell King
ARMv6 and greater introduced a new instruction ("bx") which can be used to return from function calls. Recent CPUs perform better when the "bx lr" instruction is used rather than the "mov pc, lr" instruction, and this sequence is strongly recommended to be used by the ARM architecture manual (section A.4.1.1). We provide a new macro "ret" with all its variants for the condition code which will resolve to the appropriate instruction. Rather than doing this piecemeal, and miss some instances, change all the "mov pc" instances to use the new macro, with the exception of the "movs" instruction and the kprobes code. This allows us to detect the "mov pc, lr" case and fix it up - and also gives us the possibility of deploying this for other registers depending on the CPU selection. Reported-by: Will Deacon <will.deacon@arm.com> Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1 Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood Tested-by: Shawn Guo <shawn.guo@freescale.com> Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385 Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-13ARM: fix asm/memory.h build errorRussell King
Jason Gunthorpe reports a build failure when ARM_PATCH_PHYS_VIRT is not defined: In file included from arch/arm/include/asm/page.h:163:0, from include/linux/mm_types.h:16, from include/linux/sched.h:24, from arch/arm/kernel/asm-offsets.c:13: arch/arm/include/asm/memory.h: In function '__virt_to_phys': arch/arm/include/asm/memory.h:244:40: error: 'PHYS_OFFSET' undeclared (first use in this function) arch/arm/include/asm/memory.h:244:40: note: each undeclared identifier is reported only once for each function it appears in arch/arm/include/asm/memory.h: In function '__phys_to_virt': arch/arm/include/asm/memory.h:249:13: error: 'PHYS_OFFSET' undeclared (first use in this function) Fixes: ca5a45c06cd4 ("ARM: mm: use phys_addr_t appropriately in p2v and v2p conversions") Tested-By: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-08-01ARM: Add .text annotations where required after __CPUINIT removalRussell King
Commit 8bd26e3a7 (arm: delete __cpuinit/__CPUINIT usage from all ARM users) caused some code to leak into sections which are discarded through the removal of __CPUINIT annotations. Add appropriate .text annotations to bring these back into the kernel text. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-07-14arm: delete __cpuinit/__CPUINIT usage from all ARM usersPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-17ARM: mpu: protect the vectors page with an MPU regionJonathan Austin
Without an MMU it is possible for userspace programs to start executing code in places that they have no business executing. The MPU allows some level of protection against this. This patch protects the vectors page from access by userspace processes. Userspace tasks that dereference a null pointer are already protected by an svc at 0x0 that kills them. However when tasks use an offset from a null pointer (eg a function in a null struct) they miss this carefully placed svc and enter the exception vectors in user mode, ending up in the kernel. This patch causes programs that do this to receive a SEGV instead of happily entering the kernel in user-mode, and hence avoid a 'Bad Mode' panic. As part of this change it is necessary to make sigreturn happen via the stack when there is not an sa_restorer function. This change is invisible to userspace, and irrelevant to code compiled using a uClibc toolchain, which always uses an sa_restorer function. Because we don't get to remap the vectors in !MMU kuser_helpers are not in a defined location, and hence aren't usable. This means we don't need to worry about keeping them accessible from PL0 Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> CC: Nicolas Pitre <nico@linaro.org> CC: Catalin Marinas <catalin.marinas@arm.com>
2013-06-07ARM: mpu: add MPU initialisation for secondary coresJonathan Austin
The MPU initialisation on the primary core is performed in two stages, one minimal stage to ensure the CPU can boot and a second one after sanity_check_meminfo. As the memory configuration is known by the time we boot secondary cores only a single step is necessary, provided the values for DRSR are passed to secondaries. This patch implements this arrangement. The configuration generated for the MPU regions is made available to the secondary core, which can then use the asm MPU intialisation code to program a complete region configuration. This is necessary for SMP configurations without an MMU, as the MPU initialisation is the only way to ensure that memory is specified as 'shared'. Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> CC: Nicolas Pitre <nico@linaro.org>
2013-06-07ARM: mpu: add early bring-up code for the ARMv7 PMSA-compliant MPUJonathan Austin
This patch adds initial support for using the MPU, which is necessary for SMP operation on PMSAv7 processors because it is the only way to ensure memory is shared. This is an initial patch and full SMP support is added later in this series. The setup of the MPU is performed in a way analagous to that for the MMU: Very early initialisation before the C environment is brought up, followed by a sanity check and more complete initialisation in C. This patch provides the simplest possible memory region configuration: MPU_PROBE_REGION: Reserved for probing MPU details, not enabled MPU_BG_REGION: A 'background' region that specifies all memory strongly ordered MPU_RAM_REGION: A single shared, cacheable, normal region for the valid RAM. In this early initialisation code we simply map the whole of the address space with the BG_REGION and (at least) the kernel with the RAM_REGION. The MPU has region alignment constraints that require us to round past the end of the kernel. As region 2 has a higher priority than region 1, it overrides the strongly- ordered behaviour for RAM only. Subsequent patches will add more complete initialisation from the C-world and support for bringing up secondary CPUs. Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> CC: Hyok S. Choi <hyok.choi@samsung.com>
2013-06-07ARM: nommu: add entry point for secondary CPUs to head-nommu.SWill Deacon
This patch adds a secondary_startup entry point to head-nommu.S so that we can boot secondary CPUs on an SMP nommu configuration. Signed-off-by: Will Deacon <will.deacon@arm.com> CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> CC: Nicolas Pitre <nico@linaro.org>
2013-04-17ARM: Add base support for ARMv7-MCatalin Marinas
This patch adds the base support for the ARMv7-M architecture. It consists of the corresponding arch/arm/mm/ files and various #ifdef's around the kernel. Exception handling is implemented by a subsequent patch. [ukleinek: squash in some changes originating from commit b5717ba (Cortex-M3: Add support for the Microcontroller Prototyping System) from the v2.6.33-arm1 patch stack, port to post 3.6, drop zImage support, drop reorganisation of pt_regs, assert CONFIG_CPU_V7M doesn't leak into installed headers and a few cosmetic changes] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Jonathan Austin <jonathan.austin@arm.com> Tested-by: Jonathan Austin <jonathan.austin@arm.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2013-01-31ARM: let CPUs not being able to run in ARM mode enter in THUMB modeUwe Kleine-König
Some ARM cores are not capable to run in ARM mode (e.g. Cortex-M3). So obviously these cannot enter the kernel in ARM mode. Make an exception for them and let them enter in THUMB mode. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Message-Id: 1358162123-30113-1-git-send-email-u.kleine-koenig@pengutronix.de Acked-by: Nicolas Pitre <nico@linaro.org>
2012-12-07ARM: 7591/1: nommu: Enable the strict alignment (CR_A) bit only if ARCH < v6Armando Visconti
This patch keeps disabled the strict alignment CP15 bit for all armv6 and armv7 processor without the mmu. This behaviour is now same as in the mmu case. Signed-off-by: Armando Visconti <armando.visconti@st.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-28ARM: move CP15 definitions to separate header fileRussell King
Avoid namespace conflicts with drivers over the CP15 definitions by moving CP15 related prototypes and definitions to a private header file. Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> [Tegra] Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com> [EP93xx] Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com>
2011-07-19ARM: 6999/1: head, zImage: Always Enter the kernel in ARM stateDave Martin
Currently, the documented kernel entry requirements are not explicit about whether the kernel should be entered in ARM or Thumb, leading to an ambiguitity about how to enter Thumb-2 kernels. As a result, the kernel is reliant on the zImage decompressor to enter the kernel proper in the correct instruction set state. This patch changes the boot entry protocol for head.S and Image to be the same as for zImage: in all cases, the kernel is now entered in ARM. Documentation/arm/Booting is updated to reflect this new policy. A different rule will be needed for Cortex-M class CPUs as and when support for those lands in mainline, since these CPUs don't support the ARM instruction set at all: a note is added to the effect that the kernel must be entered in Thumb on such systems. Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-15ARM: Defer lookup of machine_type to setup.cRussell King
Since the debug macros no longer depend on the machine type information, the machine type lookup can be deferred to setup_arch() in setup.c which simplifies the code somewhat. We also move the __error_a functionality into setup.c for displaying a message when a bad machine ID is passed to the kernel via the LL debug code. We also log this into the kernel ring buffer which makes it possible to retrieve the message via a debugger. Original idea from Grant Likely. Acked-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08ARM: no need for nommu to jump through the hoops that mmu doesRussell King
nommu can jump directly to __mmap_switched without the absolute address branching which the mmuful kernel does. Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-23ARM: convert to use __HEAD and HEAD_TEXT macros.Tim Abbott
This has the consequence of changing the section name used for head code from ".text.head" to ".head.text". Since this commit changes all users in the architecture, this change should be harmless. The .text.head output section is eliminated and the head text code is included at the start of the .init output section. Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-07-24nommu: Do not override the CP15 control reg value returned from initfuncCatalin Marinas
The patch removes the "mrc" instruction in head-nommu.S overriding the r0 register containing the value to be written in the CP15 system control register. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24Thumb-2: Implementation of the unified start-up and exceptions codeCatalin Marinas
This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2008-09-01[ARM] 5227/1: Add the ENDPROC declarations to the .S filesCatalin Marinas
This declaration specifies the "function" type and size for various assembly functions, mainly needed for generating the correct branch instructions in Thumb-2. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07[ARM] Eliminate useless includes of asm/mach-types.hRussell King
There are 43 includes of asm/mach-types.h by files that don't reference anything from that file. Remove these unnecessary includes. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-05-08[ARM] Ensure head text is always placed at the start of kernelRussell King
Commit 86c0baf123e474b6eb404798926ecf62b426bf3a highlighted that we may end up with the head text placed elsewhere in the kernel image. Introduce a new .text.head section to contain the initial kernel startup code, and always place this section at the beginning of the kernel image. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-11-30[ARM] Include asm/elf.h instead of asm/procinfo.hRussell King
These files want to provide/access ELF hwcap information, so should be including asm/elf.h rather than asm/procinfo.h Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-28[ARM] nommu: confirms the CR_V bit in nommu modeHyok S. Choi
In nommu mode, the exception vector location depends on the platforms. Some of the implementations may have some special exception control forwarding method in their ROM/flash and for some of them has its own re-mapping mechanism by the h/w. This patch introduces a special configuration CONFIG_CPU_HIGH_VECTOR which turns on the CR_V bit in nommu mode. The CR_V bit is turned off by default. This feature depends on CP15 and does not supported by ARM740. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-27[ARM] nommu: manage the CP15 thingsHyok S. Choi
All the current CP15 access codes in ARM arch can be categorized and conditioned by the defines as follows: Related operation Safe condition a. any CP15 access !CPU_CP15 b. alignment trap CPU_CP15_MMU c. D-cache(C-bit) CPU_CP15 d. I-cache CPU_CP15 && !( CPU_ARM610 || CPU_ARM710 || CPU_ARM720 || CPU_ARM740 || CPU_XSCALE || CPU_XSC3 ) e. alternate vector CPU_CP15 && !CPU_ARM740 f. TTB CPU_CP15_MMU g. Domain CPU_CP15_MMU h. FSR/FAR CPU_CP15_MMU For example, alternate vector is supported if and only if "CPU_CP15 && !CPU_ARM740" is satisfied. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>