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2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-20openrisc: Fix broken paths to arch/or32Geert Uytterhoeven1-1/+1
OpenRISC was mainlined as "openrisc", not "or32". vmlinux.lds is generated from vmlinux.lds.S. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Stafford Horne <shorne@gmail.com>
2018-07-01openrisc: entry: Fix delay slot exception detectionStafford Horne1-3/+6
Originally in patch e6d20c55a4 ("openrisc: entry: Fix delay slot detection") I fixed delay slot detection, but only for QEMU. We missed that hardware delay slot detection using delay slot exception flag (DSX) was still broken. This was because QEMU set the DSX flag in both pre-exception supervision register (ESR) and supervision register (SR) register, but on real hardware the DSX flag is only set on the SR register during exceptions. Fix this by carrying the DSX flag into the SR register during exception. We also update the DSX flag read locations to read the value from the SR register not the pt_regs SR register which represents ESR. The ESR should never have the DSX flag set. In the process I updated/removed a few comments to match the current state. Including removing a comment saying that the DSX detection logic was inefficient and needed to be rewritten. I have tested this on QEMU with a patch ensuring it matches the hardware specification. Link: https://lists.gnu.org/archive/html/qemu-devel/2018-07/msg00000.html Fixes: e6d20c55a4 ("openrisc: entry: Fix delay slot detection") Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-11-03openrisc: sleep instead of spin on secondary waitStafford Horne1-2/+49
Currently we do a spin on secondary cpus when waiting to boot. This theoretically causes issues with power consumption and does cause issues with qemu cycle burning (it starves cpu 0 from actually being able to boot.) This change puts each secondary cpu to sleep if they have a power management unit, then signals them to wake via IPI when its time to boot. If the cpus have no power management unit they will loop as before. Note: The wakeup IPI requires a special interrupt handler as on secondary cpu's the interrupt infrastructure is not yet established. This interrupt handler is set and reset by updating SPR_EVBAR. Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-11-03openrisc: initial SMP supportStefan Kristiansson1-5/+92
This patch introduces the SMP support for the OpenRISC architecture. The SMP architecture requires cores which have multi-core features which have been introduced a few years back including: - New SPRS SPR_COREID SPR_NUMCORES - Shadow SPRs - Atomic Instructions - Cache Coherency - A wired in IPI controller This patch adds all of the SMP specific changes to core infrastructure, it looks big but it needs to go all together as its hard to split this one up. Boot loader spinning of second cpu is not supported yet, it's assumed that Linux is booted straight after cpu reset. The bulk of these changes are trivial changes to refactor to use per cpu data structures throughout. The addition of the smp.c and changes in time.c are the changes. Some specific notes: MM changes ---------- The reason why this is created as an array, and not with DEFINE_PER_CPU is that doing it this way, we'll save a load in the tlb-miss handler (the load from __per_cpu_offset). TLB Flush --------- The SMP implementation of flush_tlb_* works by sending out a function-call IPI to all the non-local cpus by using the generic on_each_cpu() function. Currently, all flush_tlb_* functions will result in a flush_tlb_all(), which has always been the behaviour in the UP case. CPU INFO -------- This creates a per cpu cpuinfo struct and fills it out accordingly for each activated cpu. show_cpuinfo is also updated to reflect new version information in later versions of the spec. SMP API ------- This imitates the arm64 implementation by having a smp_cross_call callback that can be set by set_smp_cross_call to initiate an IPI and a handle_IPI function that is expected to be called from an IPI irqchip driver. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> [shorne@gmail.com: added cpu stop, checkpatch fixes, wrote commit message] Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-11-03openrisc: use shadow registers to save regs on exceptionStefan Kristiansson1-26/+69
Previously, the area between 0x0-0x100 have been used as a "scratch" memory area to temporarily store regs during exception entry. In a multi-core environment, this will not work. This change is to use shadow registers for nested context. Currently only the "critical" temp load/stores are covered, the EMERGENCY_PRINT ones are left as is (when they are used, it's game over anyway), they need to be handled as well in the future. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-27scripts/spelling.txt: add "aligment" pattern and fix typo instancesMasahiro Yamada1-3/+3
Fix typos and add the following to the scripts/spelling.txt: aligment||alignment I did not touch the "N_BYTE_ALIGMENT" macro in drivers/net/wireless/realtek/rtlwifi/wifi.h to avoid unpredictable impact. I fixed "_aligment_handler" in arch/openrisc/kernel/entry.S because it is surrounded by #if 0 ... #endif. It is surely safe and I confirmed "_alignment_handler" is correct. I also fixed the "controler" I found in the same hunk in arch/openrisc/kernel/head.S. Link: http://lkml.kernel.org/r/1481573103-11329-8-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-25openrisc: head: Init r0 to 0 on startStafford Horne1-1/+4
Originally openrisc spec 0 specified that r0 would be wired to ground. This is no longer the case. r0 is not guaranteed to be 0 at init, so we need to initialize it to 0 before using it. Also, if we are clearing r0 we cant use r0 to clear itself. Change the the CLEAR_GPR macro to use movhi for clearing. Reported-by: Jakob Viketoft <jakob.viketoft@aacmicrotec.com> Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-25openrisc: head: Remove unused stringsStafford Horne1-11/+0
These string definitions are no longer used removed them. Noticed this while working on a CONFIG_DEBUG_INFO build issue. Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-25openrisc: head: Move init strings to rodata sectionStafford Horne1-0/+1
The strings used during the head/init phase of openrisc bootup were stored in the executable section of the binary. This causes compilation to fail when using CONFIG_DEBUG_INFO with error: Error: unaligned opcodes detected in executable segment Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-06openrisc: head: refactor out tlb flush into it's own functionStefan Kristiansson1-16/+22
This brings it inline with the other setup oprations done like the cache enables _ic_enable and _dc_enable. Also, this is going to make it easier to initialize additional cpu's when smp is introduced. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> [shorne@gmail.com: Added commit body] Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-06openrisc: head: use THREAD_SIZE instead of magic constantStefan Kristiansson1-1/+3
The stack size was hard coded to 0x2000, use the standard THREAD_SIZE definition loaded from thread_info.h. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> [shorne@gmail.com: Added body to the commit message] Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-06openrisc: tlb miss handler optimizationsStefan Kristiansson1-95/+46
By slightly reorganizing the code, the number of registers used in the tlb miss handlers can be reduced by two, thus removing the need to save them to memory. Also, some dead and commented out code is removed. No functional change. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Jonas Bonn <jonas@southpole.se> Signed-off-by: Stafford Horne <shorne@gmail.com>
2015-02-10openrisc: drop _PAGE_FILE and pte_file()-related helpersKirill A. Shutemov1-5/+0
We've replaced remap_file_pages(2) implementation with emulation. Nobody creates non-linear mapping anymore. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Jonas Bonn <jonas@southpole.se> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-26openrisc: add missing header inclusionStefan Kristiansson1-0/+1
Prevents build issue with updated toolchain Reported-by: Jack Thomasson <jkt@moonlitsw.com> Tested-by: Christian Svensson <blue@cmd.nu> Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Jonas Bonn <jonas@southpole.se>
2013-02-14openrisc: fix up vmalloc page table loadingJonas Bonn1-4/+2
vmalloc'ed pages are faulted into a process' page tables on demand. In order to facilitate this, do_page_fault needs to know whether it was called via a page fault exception or a TLB-miss exception. This patch adds a wrapper around the _x_page_fault_handler entry points that the TLB-miss exceptions can call into in order to have the relevant parameter set to satisfy do_page_fault. This fixes a bug and is "good enough" for now. That said, this whole handling of vmalloc needs to be audited for correctness at some point. Signed-off-by: Jonas Bonn <jonas@southpole.se>
2013-02-10openrisc: avoid using function parameter regs in reset vectorStefan Kristiansson1-3/+3
The kernel might be invoked through the reset vector, so to preserve parameters passed to it, temp regs that are not in the function parameter range needs to be used. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-02-17openrisc: enable passing of flattened device tree pointerStefan Kristiansson1-1/+16
This patch enables passing a fdt pointer to the kernel. This makes for the kernel parameter API: void kernel(unsigned int fdt); which, in accordance with the OpenRISC ABI results in: r3 = pointer to fdt Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Jonas Bonn <jonas@southpole.se>
2011-07-22OpenRISC: Boot codeJonas Bonn1-0/+1607
Architecture code and early setup routines for booting Linux. Signed-off-by: Jonas Bonn <jonas@southpole.se> Reviewed-by: Arnd Bergmann <arnd@arndb.de>