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2018-11-19MIPS: Loongson: Add Loongson-3A R2.1 basic supportHuacai Chen
Loongson-3A R2.1 is the bugfix revision of Loongson-3A R2. All Loongson-3 CPU family: Code-name Brand-name PRId Loongson-3A R1 Loongson-3A1000 0x6305 Loongson-3A R2 Loongson-3A2000 0x6308 Loongson-3A R2.1 Loongson-3A2000 0x630c Loongson-3A R3 Loongson-3A3000 0x6309 Loongson-3A R3.1 Loongson-3A3000 0x630d Loongson-3B R1 Loongson-3B1000 0x6306 Loongson-3B R2 Loongson-3B1500 0x6307 Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/21128/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <james.hogan@mips.com> Cc: Steven J . Hill <Steven.Hill@cavium.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com>
2018-11-09MIPS: Avoid using .set mips0 to restore ISAPaul Burton
We currently have 2 commonly used methods for switching ISA within assembly code, then restoring the original ISA. 1) Using a pair of .set push & .set pop directives. For example: .set push .set mips32r2 <some_insn> .set pop 2) Using .set mips0 to restore the ISA originally specified on the command line. For example: .set mips32r2 <some_insn> .set mips0 Unfortunately method 2 does not work with nanoMIPS toolchains, where the assembler rejects the .set mips0 directive like so: Error: cannot change ISA from nanoMIPS to mips0 In preparation for supporting nanoMIPS builds, switch all instances of method 2 in generic non-platform-specific code to use push & pop as in method 1 instead. The .set push & .set pop is arguably cleaner anyway, and if nothing else it's good to consistently use one method. Signed-off-by: Paul Burton <paul.burton@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/21037/ Cc: linux-mips@linux-mips.org
2018-06-28MIPS: Annotate cpu_wait implementations with __cpuidlePaul Burton
Annotate cpu_wait implementations using the __cpuidle macro which places these functions in the .cpuidle.text section. This allows cpu_in_idle() to return true for PC values which fall within these functions, allowing nmi_backtrace() to produce cleaner output for CPUs running idle functions. For example: # echo l >/proc/sysrq-trigger [ 38.587170] sysrq: SysRq : Show backtrace of all active CPUs [ 38.593657] NMI backtrace for cpu 1 [ 38.597611] CPU: 1 PID: 161 Comm: sh Not tainted 4.18.0-rc1+ #27 [ 38.604306] Stack : 00000000 00000004 00000006 80486724 00000000 00000000 00000000 00000000 [ 38.613647] 80e17eda 00000034 00000000 00000000 80d20000 80b67e98 8e559c90 0ffe1e88 [ 38.622986] 00000000 00000000 80e70000 00000000 8f61db18 38312e34 722d302e 202b3163 [ 38.632324] 8e559d3c 8e559adc 00000001 6b636162 80d20000 80000000 00000000 80d1cfa4 [ 38.641664] 00000001 80d20000 80d19520 00000000 00000003 80836724 00000004 80e10004 [ 38.650993] ... [ 38.653724] Call Trace: [ 38.656499] [<8040cdd0>] show_stack+0xa0/0x144 [ 38.661475] [<80b67e98>] dump_stack+0xe8/0x120 [ 38.666455] [<80b6f6d4>] nmi_cpu_backtrace+0x1b4/0x1cc [ 38.672189] [<80b6f81c>] nmi_trigger_cpumask_backtrace+0x130/0x1e4 [ 38.679081] [<808295d8>] __handle_sysrq+0xc0/0x180 [ 38.684421] [<80829b84>] write_sysrq_trigger+0x50/0x64 [ 38.690176] [<8061c984>] proc_reg_write+0xd0/0xfc [ 38.695447] [<805aac1c>] __vfs_write+0x54/0x194 [ 38.700500] [<805aaf24>] vfs_write+0xe0/0x18c [ 38.705360] [<805ab190>] ksys_write+0x7c/0xf0 [ 38.710238] [<80416018>] syscall_common+0x34/0x58 [ 38.715558] Sending NMI from CPU 1 to CPUs 0,2-3: [ 38.720916] NMI backtrace for cpu 0 skipped: idling at r4k_wait_irqoff+0x2c/0x34 [ 38.729186] NMI backtrace for cpu 3 skipped: idling at r4k_wait_irqoff+0x2c/0x34 [ 38.737449] NMI backtrace for cpu 2 skipped: idling at r4k_wait_irqoff+0x2c/0x34 Without this we get register value & backtrace output from all CPUs, which is generally useless for those running the idle function & serves only to overwhelm & obfuscate the meaningful output from non-idle CPUs. Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Huacai Chen <chenhc@lemote.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/19598/
2017-08-29MIPS: Include linux/cpu.h for arch_cpu_idle()Paul Burton
arch/mips/kernel/idle.c provides our implementation of the arch_cpu_idle() function, but doesn't include the linux/cpu.h header which declares it. This leads to a warning from sparse: arch/mips/kernel/idle.c:256:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static? Fix this by including linux/cpu.h to get the declaration of arch_cpu_idle(). Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: trivial@kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17169/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Loongson: Add Loongson-3A R2 basic supportHuacai Chen
Loongson-3 CPU family: Code-name Brand-name PRId Loongson-3A R1 Loongson-3A1000 0x6305 Loongson-3A R2 Loongson-3A2000 0x6308 Loongson-3B R1 Loongson-3B1000 0x6306 Loongson-3B R2 Loongson-3B1500 0x6307 Features of R2 revision of Loongson-3A: - Primary cache includes I-Cache, D-Cache and V-Cache (Victim Cache). - I-Cache, D-Cache and V-Cache are 16-way set-associative, linesize is 64 bytes. - 64 entries of VTLB (classic TLB), 1024 entries of FTLB (8-way set-associative). - Supports DSP/DSPv2 instructions, UserLocal register and Read-Inhibit/ Execute-Inhibit. [ralf@linux-mips.org: Resolved merge conflicts.] Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Steven J . Hill <sjhill@realitydiluted.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12751/ Patchwork: https://patchwork.linux-mips.org/patch/13136/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-11-12Merge branch '4.3-fixes' into mips-for-linux-nextRalf Baechle
2015-11-12MIPS: idle: add case for CPU_5KEAurelien Jarno
While the 5KE processors have never been taped out, they exists though a CP0.PRId and experimental RTLs or QEMU implementations. Add a case entry in the idle code, as they can use the standard idle loop like the 5K processors. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11099/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-11-11MIPS: Always use r4k_wait_irqoff for MIPSr6Paul Burton
Prior to release 6 of the MIPS architecture it has been implementation dependent whether masked interrupts cause a wait instruction to return, so the kernel has effectively had to maintain a whitelist of cores upon which it is safe to use the r4k_wait_irqoff cpu_wait implementation. With MIPSr6 this is no longer implementation dependent and r4k_wait_irqoff can always be used. Remove the existing I6400 case which will no longer ever be hit, and was incorrect anyway since I6400 & r6 in general doesn't have the WII bit. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: linux-kernel@vger.kernel.org Cc: James Hogan <james.hogan@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/11210/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-11-09MIPS: Switch BMIPS5000 to use r4k_wait_irqoff()Petri Gynther
BCM7425 CPU Interface Zephyr Processor, pages 5-309 and 5-310 BCM7428B0 CPU Interface Zephyr Processor, pages 5-337 and 5-338 WAIT instruction: Thread enters wait state. No instructions are executed until an interrupt occurs. The processor's clocks are stopped if both threads are in idle mode. Description: Execution of this instruction puts the thread into wait state, an idle mode in which no instructions are fetched or executed. The thread remains in wait state until an interrupt occurs that is not masked by the interrupt mask field in the Status register. Then, if interrupts are enabled by the IE bit in the Status register, the interrupt is serviced. The ERET instruction returns to the instruction following the WAIT instruction. If interrupts are disabled, the processor resumes executing instructions with the next sequential instruction. Programming notes: The WAIT instruction should be executed while interrupts are disabled by the IE bit in the Status register. This avoids a potential timing hazard, which occurs if an interrupt is taken between testing the counter and executing the WAIT instruction. In this hazard case, the interrupt will have been completed before the WAIT instruction is executed, so the processor will remain indefinitely in wait state until the next interrupt. Signed-off-by: Petri Gynther <pgynther@google.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Cc: cernekee@gmail.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11322/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-08-26MIPS: Add cases for CPU_I6400Markos Chandras
Add a CPU_I6400 case to various switch statements, doing the same thing as for CPU_P5600. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10635/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31MIPS: idle: Workaround wait + FDC problemsJames Hogan
On certain cores (namely proAptiv and P5600) incoming data via a Fast Debug Channel (FDC) while the core is blocked on a wait instruction will cause the wait not to wake up even when another interrupt is received. This makes an idle target stop as soon as you send FDC data to it, until the debug probe interrupts it and restarts the wait instruction. This is worked around by avoiding using r4k_wait on these cores if CONFIG_MIPS_EJTAG_FDC_TTY is enabled (which would imply the user intends to use the FDC). [ralf@linux-mips.org: Fix conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9144/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-16MIPS: Add cases for CPU_QEMU_GENERICLeonid Yegoshin
Add a CPU_QEMU_GENERIC case to various switch statements. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2014-10-23MIPS: idle: Remove leftover __pastwait symbol and its referencesMarkos Chandras
The __pastwait symbol was only used by the address_is_in_r4k_wait_irqoff function but this is no longer used since the SMTC removal in commit b633648c5ad3 ('MIPS: MT: Remove SMTC support'). That symbol also led to build failures under certain random configuration due to the way the compiler compiled the r4k_wait_irqoff function. If that function was called multiple times, the __pastwait symbol was redefined breaking the build like this: CHK include/generated/compile.h CC arch/mips/kernel/idle.o {standard input}: Assembler messages: {standard input}:527: Error: symbol `__pastwait' is already defined Link: http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=1244879922.24479.30.camel%40falcon Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Markos Chandras <markos.chandras@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/7791/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-29Merge branch 'wip-mips-pm' of https://github.com/paulburton/linux into ↵Ralf Baechle
mips-for-linux-next
2014-05-28MIPS: cpuidle wait instruction statePaul Burton
Defines a macro intended to allow trivial use of the regular MIPS wait instruction from cpuidle drivers, which may simply invoke the macro within their array of states. Signed-off-by: Paul Burton <paul.burton@imgtec.com>
2014-05-24MIPS: MT: Remove SMTC supportRalf Baechle
Nobody is maintaining SMTC anymore and there also seems to be no userbase. Which is a pity - the SMTC technology primarily developed by Kevin D. Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT ASE's power and elegance. Based on Markos Chandras <Markos.Chandras@imgtec.com> patch https://patchwork.linux-mips.org/patch/6719/ which while very similar did no longer apply cleanly when I tried to merge it plus some additional post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to merge once upon a time. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-23MIPS: RM9000: Remove support for idle loop.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-31MIPS: Fix gigaton of warning building with microMIPS.Ralf Baechle
With binutils 2.24 the attempt to switch with microMIPS mode to MIPS III mode through .set mips3 results in *lots* of warnings like {standard input}: Assembler messages: {standard input}:397: Warning: the 64-bit MIPS architecture does not support the `smartmips' extension during a kernel build. Fixed by using .set arch=r4000 instead. This breaks support for building the kernel with binutils 2.13 which was supported for 32 bit kernels only anyway and 2.14 which was a bad vintage for MIPS anyway. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-26MIPS: Add support for the M5150 processorLeonid Yegoshin
The M5150 core is a 32-bit MIPS RISC which implements the MIPS Architecture Release-5 in a 5-stage pipeline. In addition, it includes the MIPS Architecture Virtualization Module that enables virtualization of operating systems, which provides a scalable, trusted, and secure execution environment. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6596/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-26MIPS: Add cases for CPU_P5600James Hogan
Add a CPU_P5600 case to various switch statements, doing the same thing as for CPU_PROAPTIV. Signed-off-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6408/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-06MIPS: Add 1074K CPU support explicitly.Steven J. Hill
The 1074K is a multiprocessing coherent processing system (CPS) based on modified 74K cores. This patch makes the 1074K an actual unique CPU type, instead of a 74K derivative, which it is not. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com> Reviewed-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6389/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-01-22MIPS: Add support for interAptiv coresLeonid Yegoshin
The interAptiv is a power-efficient multi-core microprocessor for use in system-on-chip (SoC) applications. The interAptiv combines a multi-threading pipeline with a coherence manager to deliver improved computational throughput and power efficiency. The interAptiv can contain one to four MIPS32R3 interAptiv cores, system level coherence manager with L2 cache, optional coherent I/O port, and optional floating point unit. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6163/
2014-01-22MIPS: Add support for the proAptiv coresLeonid Yegoshin
The proAptiv Multiprocessing System is a power efficient multi-core microprocessor for use in system-on-chip (SoC) applications. The proAptiv Multiprocessing System combines a deep pipeline with multi-issue out of order execution for improved computational throughput. The proAptiv Multiprocessing System can contain one to six MIPS32r3 proAptiv cores, system level coherence manager with L2 cache, optional coherent I/O port, and optional floating point unit. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6134/
2013-09-17MIPS: Optimize current_cpu_type() for better code.Ralf Baechle
o Move current_cpu_type() to a separate header file o #ifdefing on supported CPU types lets modern GCC know that certain code in callers may be discarded ideally turning current_cpu_type() into a function returning a constant. o Use current_cpu_type() rather than direct access to struct cpuinfo_mips. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5833/
2013-08-26MIPS: Use r4k_wait for OCTEON3 CPUs.David Daney
Signed-off-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5636/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10MIPS: Alchemy: fix wait functionManuel Lauss
Only an interrupt can wake the core from 'wait', enable interrupts locally before executing 'wait'. [ralf@linux-mips.org: This leave the race between an interrupt that's setting TIF_NEED_RESCHEd and entering the WAIT status. but at least it's going to bring Alchemy back from the dead, so I'm going to apply this patch.] Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com> Cc: Linux-MIPS <linux-mips@linux-mips.org> Cc: Maciej W. Rozycki <macro@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/5408/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Break r4k_wait into two functions and fix it.Ralf Baechle
local_irq_enable() may expand into very different code, so it rather should stay in C. Also this keeps the assembler code size constant which keeps the rollback code simple. So it's best to split r4k_wait into two parts, one C and one assembler. Finally add the local_irq_enable() to r4k_wait to ensure the WAIT instruction in __r4k_wait() will work properly. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Consolidate all declarations in <asm/idle.h>.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Don't call local_irq_disable() in cpu_wait() implementations.Ralf Baechle
The generic idle loop has already disabled interrupts so this is redundant. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Re-enable irqs at the end of r3081, au1k and loongson2 cpu_wait.Ralf Baechle
Without this, the WARN_ON_ONCE(irqs_disabled()); in the idle loop will be triggered. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Make call of function pointer readable.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: Consistently reformat inline assembler.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Idle: cleaup SMTC idle hook as per Linux coding style.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-05-22MIPS: Consolidate idle loop / WAIT instruction support in a single file.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>