aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arc/kernel/head.S
Commit message (Collapse)AuthorAge
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2019-06-19
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ARC: u-boot args: check that magic number is correctEugeniy Paltsev2019-02-25
| | | | | | | | | | | | | | | | | | | | In case of devboards we really often disable bootloader and load Linux image in memory via JTAG. Even if kernel tries to verify uboot_tag and uboot_arg there is sill a chance that we treat some garbage in registers as valid u-boot arguments in JTAG case. E.g. it is enough to have '1' in r0 to treat any value in r2 as a boot command line. So check that magic number passed from u-boot is correct and drop u-boot arguments otherwise. That helps to reduce the possibility of using garbage as u-boot arguments in JTAG case. We can safely check U-boot magic value (0x0) in linux passed via r1 register as U-boot pass it from the beginning. So there is no backward-compatibility issues. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: Add explcit unaligned access support (and ability to disable too)Eugeniy Paltsev2019-02-25
| | | | | | | | | | | | | | | | | As of today we enable unaligned access unconditionally on ARCv2. Do this under a Kconfig option to allow disable it for test, benchmarking etc. Also while at it - Select HAVE_EFFICIENT_UNALIGNED_ACCESS - Although gcc defaults to unaligned access (since GNU 2018.03), add the right toggles for enabling or disabling as appropriate - update bootlog to prints both HW feature status (exists, enabled/disabled) and SW status (used / not used). - wire up the relaxed memcpy for unaligned access Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: squashed patches, handle gcc -mno-unaligned-access quick]
* ARC: enable uboot support unconditionallyEugeniy Paltsev2019-02-21
| | | | | | | | | | | | | | | After reworking U-boot args handling code and adding paranoid arguments check we can eliminate CONFIG_ARC_UBOOT_SUPPORT and enable uboot support unconditionally. For JTAG case we can assume that core registers will come up reset value of 0 or in worst case we rely on user passing '-on=clear_regs' to Metaware debugger. Cc: stable@vger.kernel.org Tested-by: Corentin LABBE <clabbe@baylibre.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: U-boot: check arguments paranoidlyEugeniy Paltsev2019-02-21
| | | | | | | | | | | | | | | | | | | | | | | | Handle U-boot arguments paranoidly: * don't allow to pass unknown tag. * try to use external device tree blob only if corresponding tag (TAG_DTB) is set. * don't check uboot_tag if kernel build with no ARC_UBOOT_SUPPORT. NOTE: If U-boot args are invalid we skip them and try to use embedded device tree blob. We can't panic on invalid U-boot args as we really pass invalid args due to bug in U-boot code. This happens if we don't provide external DTB to U-boot and don't set 'bootargs' U-boot environment variable (which is default case at least for HSDK board) In that case we will pass {r0 = 1 (bootargs in r2); r1 = 0; r2 = 0;} to linux which is invalid. While I'm at it refactor U-boot arguments handling code. Cc: stable@vger.kernel.org Tested-by: Corentin LABBE <clabbe@baylibre.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: Enable unaligned access in early ASM codeEugeniy Paltsev2019-02-21
| | | | | | | | | | | It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@vger.kernel.org #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: rewrote changelog]
* ARC: smp-boot: Decouple Non masters waiting API from jump to entry pointVineet Gupta2017-01-24
| | | | | | | | | | | | | | | | | | | | | | For run-on-reset SMP configs, non master cores call a routine which waits until Master gives it a "go" signal (currently using a shared mem flag). The same routine then jumps off the well known entry point of all non Master cores i.e. @first_lines_of_secondary This patch moves out the last part into one single place in early boot code. This is better in terms of absraction (the wait API only waits) and returns, leaving out the "jump off to" part. In actual implementation this requires some restructuring of the early boot code as well as Master now jumps to BSS setup explicitly, vs. falling thru into it before. Technically this patch doesn't cause any functional change, it just moves the ugly #ifdef'ry from assembly code to "C" Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: boot: Non Master cpus only need to call EARLY_CPU_SETUP onceVineet Gupta2015-10-28
| | | | | | | | With prev fixes, all cores now start via common entry point @stext which already calls EARLY_CPU_SETUP for all cores - so no need to invoke it again Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modesVineet Gupta2015-10-28
| | | | | | | | | | | For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: Support for ARCv2 ISA and HS38x coresVineet Gupta2015-06-22
| | | | | | | | | | | | | | | | | | The notable features are: - SMP configurations of upto 4 cores with coherency - Optional L2 Cache and IO-Coherency - Revised Interrupt Architecture (multiple priorites, reg banks, auto stack switch, auto regfile save/restore) - MMUv4 (PIPT dcache, Huge Pages) - Instructions for * 64bit load/store: LDD, STD * Hardware assisted divide/remainder: DIV, REM * Function prologue/epilogue: ENTER_S, LEAVE_S * IRQ enable/disable: CLRI, SETI * pop count: FFS, FLS * SETcc, BMSKN, XBFU... Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: explicit'ify uboot supportVineet Gupta2015-06-19
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: RIP @running_on_hwVineet Gupta2014-10-13
| | | | | | | | | | * No active users of this flag anymore * flag itself was no longer usable with new simualtor which acts just like hardware, not providing the special chip-id = 0xffff which good old ISS used to do. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: optimize kernel bss clearing in early boot codeVineet Gupta2014-06-26
| | | | | | using ARC ZOL which reduces tot num of instructions by half Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Disable caches in early boot if so configuredVineet Gupta2014-06-03
| | | | | Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [SMP] General FixesVineet Gupta2014-04-05
| | | | | | | -Pass the expected arg to non-boot park'ing routine (It worked so far because existing SMP backends don't use the arg) -CONFIG_DEBUG_PREEMPT warning
* ARC: [cmdline] uboot cmdline handling reworkVineet Gupta2014-01-16
| | | | | | | | | | * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* arc: remove '__init' for first_lines_of_secondary()Chen Gang2013-11-06
| | | | | | | | | | | | | | | | | first_lines_of_secondary() is a '__init' function, but it may be called by __cpu_up() by _cpu_up() by cpu_up() which is a normal export symbol function. So recommend to remove '__init'. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x315c): Section mismatch in reference from the function __cpu_up() to the function .init.text:first_lines_of_secondary() The function __cpu_up() references the function __init first_lines_of_secondary(). This is often because __cpu_up lacks a __init annotation or the annotation of first_lines_of_secondary is wrong. Signed-off-by: Chen Gang <gang.chen@asianux.com>
* ARC: SMP failed to boot due to missing IVT setupNoam Camus2013-09-12
| | | | | | | | | | | | | | | | | | | | | Commit 05b016ecf5e7a "ARC: Setup Vector Table Base in early boot" moved the Interrupt vector Table setup out of arc_init_IRQ() which is called for all CPUs, to entry point of boot cpu only, breaking booting of others. Fix by adding the same to entry point of non-boot CPUs too. read_arc_build_cfg_regs() printing IVT Base Register didn't help the casue since it prints a synthetic value if zero which is totally bogus, so fix that to print the exact Register. [vgupta: Remove the now stale comment from header of arc_init_IRQ and also added the commentary for halt-on-reset] Cc: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Cc: <stable@vger.kernel.org> #3.11 Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ARC: Setup Vector Table Base in early bootVineet Gupta2013-06-26
| | | | | | | | Otherwise early boot exceptions such as instructions errors due to configuration mismatch between kernel and hardware go off to la-la land, as opposed to hitting the handler and panic()'ing properly. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: SMP supportVineet Gupta2013-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
* ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem initVineet Gupta2013-02-15
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-24 21:42:50 -0400