kernel.git/arch/mips/include/asm/cpu-info.h, branch linux-4.10.y

MIPS: Add probing & defs for VZ & guest features

2016-05-13T13:30:25Z

Add a few new cpu-features.h definitions for VZ sub-features, namely the existence of the CP0_GuestCtl0Ext, CP0_GuestCtl1, and CP0_GuestCtl2 registers, and support for GuestID to dialias TLB entries belonging to different guests. Also add certain features present in the guest, with the naming scheme cpu_guest_has_*. These are added separately to the main options bitfield since they generally parallel similar features in the root context. A few of these (FPU, MSA, watchpoints, perf counters, CP0_[X]ContextConfig registers, MAAR registers, and probably others in future) can be dynamically configured in the guest context, for which the cpu_guest_has_dyn_* macros are added. [ralf@linux-mips.org: Resolve merge conflict.] Signed-off-by: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13231/ Signed-off-by: Ralf Baechle

MIPS: Support extended ASIDs

2016-05-13T12:02:20Z

Add support for extended ASIDs as determined by the Config4.AE bit. Since the only supported CPUs known to implement this are Netlogic XLP and MIPS I6400, select this variable ASID support based upon CONFIG_CPU_XLP and CONFIG_CPU_MIPSR6. Signed-off-by: Paul Burton Signed-off-by: James Hogan Cc: Jayachandran C. Cc: Paolo Bonzini Cc: Radim Krčmář Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13211/ Signed-off-by: Ralf Baechle

MIPS: Retrieve ASID masks using function accepting struct cpuinfo_mips

2016-05-13T12:02:20Z

In preparation for supporting variable ASID masks, retrieve ASID masks using functions in asm/cpu-info.h which accept struct cpuinfo_mips. This will allow those functions to determine the ASID mask based upon the CPU in a later patch. This also allows for the r3k & r8k cases to be handled in Kconfig, which is arguably cleaner than the previous #ifdefs. Signed-off-by: Paul Burton Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: Radim Krčmář Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13210/ Signed-off-by: Ralf Baechle

MIPS: Loongson: Add Loongson-3A R2 basic support

2016-05-13T12:02:14Z

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 Cc: Aurelien Jarno Cc: Steven J . Hill Cc: Fuxin Zhang Cc: Zhangjin Wu 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

MIPS: smp-cps: Support MIPSr6 Virtual Processors

2016-05-13T12:01:50Z

Introduce support for bringing up Virtual Processors in MIPSr6 systems as CPUs, much like their VPE parallel from the now-deprecated MT ASE. The existing mips_cps_boot_vpes function fits the MIPSr6 architecture pretty well - it can now simply write the mask of running VPs to the VC_RUN register, rather than looping through each & starting or stopping as appropriate as is done for VPEs from the MT ASE. Thus the VP support is in general an extension & simplification of the existing MT ASE VPE (aka SMVP) support. Signed-off-by: Paul Burton Cc: Matt Redfearn Cc: Rusty Russell Cc: Maciej W. Rozycki Cc: Niklas Cassel Cc: Ezequiel Garcia Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12339/ Signed-off-by: Ralf Baechle

MIPS: cpu_name_string: Use raw_smp_processor_id().

2016-03-29T21:56:36Z

If cpu_name_string() is used in non-atomic context when preemption is enabled, it can trigger a BUG such as this one: BUG: using smp_processor_id() in preemptible [00000000] code: unaligned/156 caller is __show_regs+0x1e4/0x330 CPU: 2 PID: 156 Comm: unaligned Tainted: G W 4.3.0-00366-ga3592179816d-dirty #1501 Stack : ffffffff80900000 ffffffff8019bc18 000000000000005f ffffffff80a20000 0000000000000000 0000000000000009 ffffffff8019c0e0 ffffffff80835648 a8000000ff2bdec0 ffffffff80a1e628 000000000000009c 0000000000000002 ffffffff80840000 a8000000fff2ffb0 0000000000000020 ffffffff8020e43c a8000000fff2fcf8 ffffffff80a20000 0000000000000000 ffffffff808f2607 ffffffff8082b138 ffffffff8019cd1c 0000000000000030 ffffffff8082b138 0000000000000002 000000000000009c 0000000000000000 0000000000000000 0000000000000000 a8000000fff2fc40 0000000000000000 ffffffff8044dbf4 0000000000000000 0000000000000000 0000000000000000 ffffffff8010c400 ffffffff80855bb0 ffffffff8010d008 0000000000000000 ffffffff8044dbf4 ... Call Trace: [] show_stack+0x90/0xb0 [] dump_stack+0x84/0xe0 [] check_preemption_disabled+0x10c/0x110 [] __show_regs+0x1e4/0x330 [] show_registers+0x28/0xc0 [] do_ade+0xcc8/0xce0 [] resume_userspace_check+0x0/0x10 This is possible because cpu_name_string() is used by __show_regs(), which is used by both show_regs() and show_registers(). These two functions are used by various exception handling functions, only some of which ensure that interrupts or preemption is disabled. However the following have interrupts explicitly enabled or not explicitly disabled: - do_reserved() (irqs enabled) - do_ade() (irqs not disabled) This can be hit by setting /sys/kernel/debug/mips/unaligned_action to 2, and triggering an address error exception, e.g. an unaligned access or access to kernel segment from user mode. To fix the above cases, use raw_smp_processor_id() instead. It is unusual for CPU names to be different in the same system, and even if they were, its possible the process has migrated between the exception of interest and the cpu_name_string() call anyway. Signed-off-by: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12212/ Signed-off-by: Ralf Baechle

MIPS: Respect the ISA level in FCSR handling

2015-04-07T23:10:37Z

Define the central place the default FCSR value is set from, initialised in `cpu_probe'. Determine the FCSR mask applied to values written to the register with CTC1 in the full emulation mode and via ptrace(2), according to the ISA level of processor hardware or the writability of bits 31:18 if actual FPU hardware is used. Software may rely on FCSR bits whose functions our emulator does not implement, so it should not allow them to be set or software may get confused. For ptrace(2) it's just sanity. [ralf@linux-mips.org: Fixed double inclusion of .] Signed-off-by: Maciej W. Rozycki Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9711/ Signed-off-by: Ralf Baechle

MIPS: HTW: Prevent accidental HTW start due to nested htw_{start, stop}

2015-02-16T09:55:26Z

activate_mm() and switch_mm() call get_new_mmu_context() which in turn can enable the HTW before the entryhi is changed with the new ASID. Since the latter will enable the HTW in local_flush_tlb_all(), then there is a small timing window where the HTW is running with the new ASID but with an old pgd since the TLBMISS_HANDLER_SETUP_PGD hasn't assigned a new one yet. In order to prevent that, we introduce a simple htw counter to avoid starting HTW accidentally due to nested htw_{start,stop}() sequences. Moreover, since various IPI calls can enforce TLB flushing operations on a different core, such an operation may interrupt another htw_{stop,start} in progress leading inconsistent updates of the htw_seq variable. In order to avoid that, we disable the interrupts whenever we update that variable. Signed-off-by: Markos Chandras Cc: # 3.17+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9118/ Signed-off-by: Ralf Baechle

MIPS: cpu-probe: Set the write-combine CCA value on per core basis

2014-09-22T11:35:53Z

Different cores use different CCA values to achieve write-combine memory writes. For cores that do not support write-combine we set the default value to CCA:2 (uncached, non-coherent) which is the default value as set by the kernel. Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7402/ Signed-off-by: Ralf Baechle

MIPS: cpu-info: Change the cpu options variable to unsigned long long

2014-08-01T22:06:38Z

Long integers which are 4 bytes in MIPS32 can't hold new CPU options anymore, so the type of the 'options' variable is changed to unsigned long long which allows 32 more cpu options to be defined for MIPS32 Also, re-arrange the 'options' struct member to avoid potential 4-byte alignment gap in the middle of the struct. Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7324/ Signed-off-by: Ralf Baechle