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2011-02-10ARM: fixup SMP alternatives in modulesRussell King
With certain configurations, we inline the unlock functions in modules, which results in SMP alternatives being created in modules. We need to fix those up when loading a module to prevent undefined instruction faults. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-31ARM: smp_on_up: allow non-ARM SMP processorsRussell King
Allow non-ARM SMP processors to use the SMP_ON_UP feature. CPUs supporting SMP must have the new CPU ID format, so check for this first. Then check for ARM11MPCore, which fails the MPIDR check. Lastly check the MPIDR reports multiprocessing extensions and that the CPU is part of a multiprocessing system. Cc: <stable@kernel.org> Reported-and-Tested-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-06Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig arch/arm/common/Makefile arch/arm/kernel/Makefile arch/arm/kernel/smp.c
2010-12-20ARM: 6516/1: Allow SMP_ON_UP to work with Thumb-2 kernels.Dave Martin
* __fixup_smp_on_up has been modified with support for the THUMB2_KERNEL case. For THUMB2_KERNEL only, fixups are split into halfwords in case of misalignment, since we can't rely on unaligned accesses working before turning the MMU on. No attempt is made to optimise the aligned case, since the number of fixups is typically small, and it seems best to keep the code as simple as possible. * Add a rotate in the fixup_smp code in order to support CPU_BIG_ENDIAN, as suggested by Nicolas Pitre. * Add an assembly-time sanity-check to ALT_UP() to ensure that the content really is the right size (4 bytes). (No check is done for ALT_SMP(). Possibly, this could be fixed by splitting the two uses ot ALT_SMP() (ALT_SMP...SMP_UP versus ALT_SMP...SMP_UP_B) into two macros. In the first case, ALT_SMP needs to expand to >= 4 bytes, not == 4.) * smp_mpidr.h (which implements ALT_SMP()/ALT_UP() manually due to macro limitations) has not been modified: the affected instruction (mov) has no 16-bit encoding, so the correct instruction size is satisfied in this case. * A "mode" parameter has been added to smp_dmb: smp_dmb arm @ assumes 4-byte instructions (for ARM code, e.g. kuser) smp_dmb @ uses W() to ensure 4-byte instructions for ALT_SMP() This avoids assembly failures due to use of W() inside smp_dmb, when assembling pure-ARM code in the vectors page. There might be a better way to achieve this. * Kconfig: make SMP_ON_UP depend on (!THUMB2_KERNEL || !BIG_ENDIAN) i.e., THUMB2_KERNEL is now supported, but only if !BIG_ENDIAN (The fixup code for Thumb-2 currently assumes little-endian order.) Tested using a single generic realview kernel on: ARM RealView PB-A8 (CONFIG_THUMB2_KERNEL={n,y}) ARM RealView PBX-A9 (SMP) 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>
2010-12-20ARM: SMP: use more sane register allocation for __fixup_smp_on_upRussell King
Use r0,r3-r6 rather than r0,r3,r4,r6,r7, which makes it easier to understand which registers can be modified. Also document which registers hold values which must be preserved. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-30ARM: 6504/1: Thumb-2: Fix long-distance conditional branches in head.S for ↵Dave Martin
Thumb-2. The 32-bit conditional branches in Thumb-2 have a shorter range (+/-512K) than their ARM counterparts (+/-32MB). The linker does not currently generate trampolines to extend the range of these Thumb-2 conditional branches, resulting in link errors when vmlinux is sufficiently large, e.g.: head.o:(.text+0x464): relocation truncated to fit: R_ARM_THM_JUMP19 This patch forces the longer-range, unconditional branch encoding by use of an explicit IT instruction. The resulting branches are triggered on the same conditions as before. Signed-off-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-30ARM: 6500/1: Thumb-2: Correct data alignment for CONFIG_THUMB2_KERNEL in ↵Dave Martin
kernel/head.S Directives such as .long and .word do not magically cause the assembler location counter to become aligned in gas. As a result, using these directives in code sections can result in misaligned data words when building a Thumb-2 kernel (CONFIG_THUMB2_KERNEL). This is a Bad Thing, since the ABI permits the compiler to assume that fundamental types of word size or above are word- aligned when accessing them from C. If the data is not really word-aligned, this can cause impaired performance and stray alignment faults in some circumstances. In general, the following rules should be applied when using data word declaration directives inside code sections: * .quad and .double: .align 3 * .long, .word, .single, .float: .align (or .align 2) * .short: No explicit alignment required, since Thumb-2 instructions are always 2 or 4 bytes in size. immediately after an instruction. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-20arm: use addruart macro to establish debug mappingsJeremy Kerr
Since we can get both physical and virtual addresses from the addruart macro, we can use this to establish the debug mappings. In the case of CONFIG_DEBUG_ICEDCC, we don't need any mappings, but may still need to setup r7 correctly. Incorporating ASM changes from Nicolas Pitre <npitre@fluxnic.net>. Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com> Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
2010-10-18Merge branch 'hotplug' into develRussell King
Conflicts: arch/arm/kernel/head-common.S
2010-10-08ARM: add register documentation for __enable_mmuRussell King
Add some additional documentation on register usage in __enable_mmu to help complete the overall picture. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08ARM: hotplug cpu: move secondary_startup, __enable_mmu to cpuinitRussell King
Move these two functions, both of which are required for secondary CPU booting, into the cpuinit section. Ensure bad processors call __error_p for better diagnostics, rather than just __error. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08ARM: hotplug cpu: ensure that __enable_mmu is identity mappedRussell King
__enable_mmu is required to be executed in an identity mapped region to ensure that variances in CPUs do not cause a crash. We currently achieve this by assuming that it will be co-located with __create_page_tables. With hotplug CPU support, this assumption becomes invalid. Implement a better solution which ensures that it will be appropriately mapped no matter where it is placed. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08ARM: cleanup boot cpu calling __mmap_switchedRussell King
This allows us to relocate __mmap_switched and associated data away from the head section. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-04ARM: Allow SMP kernels to boot on UP systemsRussell King
UP systems do not implement all the instructions that SMP systems have, so in order to boot a SMP kernel on a UP system, we need to rewrite parts of the kernel. Do this using an 'alternatives' scheme, where the kernel code and data is modified prior to initialization to replace the SMP instructions, thereby rendering the problematical code ineffectual. We use the linker to generate a list of 32-bit word locations and their replacement values, and run through these replacements when we detect a UP system. 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>
2009-07-24Thumb-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>
2008-03-06[ARM] 4849/1: move ATAGS asm definitionsGreg Ungerer
Move the definitions of ATAG_CORE and ATAG_CORE_SIZE in head.S to head-common.S. There is no use of these in head.S itself, but they are used in head-common.S. When building for the !CONFIG_MMU case these were not defined when compiling head-nommu.S (which includes head-common.S). Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-07-12[ARM] 4423/1: add ATAGS supportBill Gatliff
Examines the ATAGS pointer (r2) at boot, and interprets a nonzero value as a reference to an ATAGS structure. A suitable ATAGS structure replaces the kernel's command line. Signed-off-by: Bill Gatliff <bgat@billgatliff.com> 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>
2007-05-03[ARM] 4227/1: minor head.S fixupsNicolas Pitre
Let's surround constructs like: orr r3, r3, #(KERNEL_RAM_PADDR & 0x00f00000) between .if .endif since (KERNEL_RAM_PADDR & 0x00f00000) is 0 in 99% of all cases. Also let's mask PHYS_OFFSET with 0x00f00000 instead of 0x00e00000. Section mappings are really 1MB not 2MB and the 2MB groupping is a higher level issue already much better enforced with #if (PHYS_OFFSET & 0x001fffff) #error "PHYS_OFFSET must be at an even 2MiB boundary!" #endif at the top of the file. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-25[ARM] 4226/1: initial .data and .bss mappings of XIP kernel should be ↵Nicolas Pitre
TEXT_OFFSET aware Since TEXT_OFFSET is meant to determine RAM location for kernel use, itshould affect .data and .bss initial mapping in the XIP case. Otherwise a XIP kernel would crash if TEXT_OFFSET gets somewhat larger than 2MB. Corresponding code is also moved up a bit to be near the similar .text mapping code making the whole a bit more straight forward to understand. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-25[ARM] 4224/2: allow XIP kernel to boot againNicolas Pitre
Since commit 2552fc27ff79b10b9678d92bcaef21df38bb7bb6 XIP kernels failed to boot because (_end - PAGE_OFFSET - 1) is much smaller than the size of the kernel text and data in the XIP case, causing the kernel not to be entirely mapped. Even in the non-XIP case, the use of (_end - PAGE_OFFSET - 1) is wrong because it produces a too large value if TEXT_OFFSET is larger than 1MB. Finally the original code was performing one loop too many. Let's break the loop when the section pointer has passed the last byte of the kernel instead. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-01-24[ARM] 4102/1: Allow for PHYS_OFFSET on any valid 2MiB addressLinus Walleij
This patchs allows the offset to the first page of physical memory to be on any 2MB boundary whereas the previous code could only handle psysical offset to any 16MB boundary (0xNN000000) or any 1MB boundary below 0x01000000 (e.g. 0x00N00000). The problem is a consequence of the orr one-byte syntax, so we fix this and we can place the first bank of memory at 0x28e00000. I have also included an explicit check that disallow compilation when PHYS_OFFSET is not on a 2MiB boundary. head.S would be the proper place to have this at since this is the first file that attempts to use PHYS_OFFSET during compile. Signed-off-by: Linus Walleij <triad@df.lth.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-12-11[ARM] Clean up KERNEL_RAM_ADDRRussell King
Clean up the KERNEL_RAM_ADDR stuff in arch/arm/kernel/head.S to make it clearer what's referring to what. In doing so, remove the usage of __virt_to_phys(), which is not guaranteed to be something that the assembler can parse. 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>
2006-09-30[ARM] 3809/3: get rid of 4 megabyte kernel image size limitLennert Buytenhek
We currently have a hardcoded 4 megabyte uncompressed kernel image size limit, which is easily exceeded by, for example, enabling some of the various kernel debugging options. When setting up the initial page tables (which is where this 4M limit is hardcoded), it's actually relatively easy to find out the true size of the uncompressed kernel image and create enough page table entries for things to fit, so this patch makes it so. In the decompressor, we also need to know the size of the uncompressed kernel image, to figure out whether there is any chance that uncompressing the kernel might overwrite the compressed kernel image stored elsewhere in memory. We don't have that info at this boot stage, though, so we approximate the size of the uncompressed kernel by taking the compressed kernel image size and allowing for a maximum 4x expansion. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-08-18[ARM] 3757/1: Use PROCINFO_INITFUNC in head.SCatalin Marinas
Patch from Catalin Marinas This is instead of a magic number. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-26[ARM] Fix SMP bootingRussell King
Processor support files now use r6 in their CPU setup code, so we can't rely on r6 being preserved. Use r7 instead. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-02Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (44 commits) [ARM] 3541/2: workaround for PXA27x erratum E7 [ARM] nommu: provide a way for correct control register value selection [ARM] 3705/1: add supersection support to ioremap() [ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructure [ARM] 3706/2: ep93xx: add cirrus logic edb9315a support [ARM] 3704/1: format IOP Kconfig with tabs, create more consistency [ARM] 3703/1: Add help description for ARCH_EP80219 [ARM] 3678/1: MMC: Make OMAP MMC work [ARM] 3677/1: OMAP: Update H2 defconfig [ARM] 3676/1: ARM: OMAP: Fix dmtimers and timer32k to compile on OMAP1 [ARM] Add section support to ioremap [ARM] Fix sa11x0 SDRAM selection [ARM] Set bit 4 on section mappings correctly depending on CPU [ARM] 3666/1: TRIZEPS4 [1/5] core ARM: OMAP: Multiplexing for 24xx GPMC wait pin monitoring ARM: OMAP: Fix SRAM to use MT_MEMORY instead of MT_DEVICE ARM: OMAP: Update dmtimers ARM: OMAP: Make clock variables static ARM: OMAP: Fix GPMC compilation when DEBUG is defined ARM: OMAP: Mux updates for external DMA and GPIO ...
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>
2006-06-29[ARM] Set bit 4 on section mappings correctly depending on CPURussell King
On some CPUs, bit 4 of section mappings means "update the cache when written to". On others, this bit is required to be one, and others it's required to be zero. Finally, on ARMv6 and above, setting it turns on "no execute" and prevents speculative prefetches. With all these combinations, no one value fits all CPUs, so we have to pick a value depending on the CPU type, and the area we're mapping. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-25[ARM] Remove MODE_(SVC|IRQ|FIQ|USR) and DEFAULT_FIQRussell King
DEFAULT_FIQ was entirely unused. MODE_* are just redefinitions of *_MODE. Use *_MODE instead. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-05[ARM] 3496/1: more constants for asm-offsets.hUwe Zeisberger
Patch from Uwe Zeisberger added the following constants: - MACHINFO_TYPE - MACHINFO_NAME - MACHINFO_PHYSIO - MACHINFO_PGOFFIO - PROCINFO_INITFUNC - PROCINFO_MMUFLAGS and removed their definition from head.S and head-nommu.S Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-28Merge nommu treeRussell King
2006-03-27[ARM] nommu: start-up codeHyok S. Choi
This patch adds nommu version start-up code head-nommu.S. The common part of the start-up codes is moved to head-common.S. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-25Merge nommu treeRussell King
Fix merge conflict in arch/arm/mm/proc-xscale.S Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-21[ARM] 3261/2: remove phys_ram from struct machine_desc (part 3)Nicolas Pitre
Patch from Nicolas Pitre This field is redundent since it must be equal to PHYS_OFFSET anyway. There is no reference to it anymore so remove it at last. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-21[ARM] Move read of processor ID out of lookup_processor_type()Russell King
Read the processor ID at boot, and save it in "processor_id" as we did before. Later, when we re-parse the CPU type in the setup.c code, re-use the value stored in "processor_id". This allows a cleaner work-around for noMMU devices without CP#15. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-13[ARM] 3259/1: remove phys_ram from struct machine_desc (part 1)Nicolas Pitre
Patch from Nicolas Pitre This field is redundent since it must be equal to PHYS_OFFSET anyway. First, let's use PHYS_OFFSET directly instead. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-03[ARM] Make kernel link address depend on PAGE_OFFSETRussell King
We are coding the kernel link address into the makefiles, which is invisibly dependent on PAGE_OFFSET. If PAGE_OFFSET is changed, the makefiles also need to be changed. Make adjustments such that the makefiles encode just the offset from PAGE_OFFSET for the kernel link address, and use PAGE_OFFSET in the linker scripts directly. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-25[ARM] Remove mach-types.h from head.SRussell King
We don't really need to check whether the machine type is Netwinder or CATS before setting up the PCI IO mapping for debugging. This allows us to eliminate asm/mach-types.h from head.S Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-29[ARM] 3061/1: cleanup the XIP link address messNicolas Pitre
Patch from Nicolas Pitre Since vmlinux.lds.S is preprocessed, we can use the defines already present in asm/memory.h (allowed by patch #3060) for the XIP kernel link address instead of relying on a duplicated Makefile hardcoded value, and also get rid of its dependency on awk to handle it at the same time. While at it let's clean XIP stuff even further and make things clearer in head.S with a nice code reduction. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-29[ARM] 3060/1: allow constants found in asm/memory.h to be used in asm codeNicolas Pitre
Patch from Nicolas Pitre This patch allows for assorted type of cleanups by letting assembly code use the same set of defines for constant values and avoid duplicated definitions that might not always be in sync, or that might simply be confusing due to the different names for the same thing. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-09-09kbuild: arm - use generic asm-offsets.h supportSam Ravnborg
Delete obsoleted stuff from arch Makefile and rename constants.h to asm-offsets.h Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-01[PATCH] ARM: Make the magic values in head.S more obviousRussell King
Make the magic address values in head.S more obvious as to where they came from. Wrap all debug code in CONFIG_DEBUG_LL. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-18[PATCH] ARM SMP: Add support for startup of secondary processorsRussell King
Create a temporary page table to startup secondary processors. This page table must have a 1:1 virtual/physical mapping for the kernel in addition to the standard mappings to ensure that the secondary CPU can enable its MMU safely. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-05-05[PATCH] ARM: Fix kernel stack offset calculationsRussell King
Various places in the ARM kernel implicitly assumed that kernel stacks are always 8K due to hard coded constants. Replace these constants with definitions. Correct the allowable range of kernel stack pointer values within the allocation. Arrange for the entire kernel stack to be zeroed, not just the upper 4K if CONFIG_DEBUG_STACK_USAGE is set. Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!