Re: [PATCH v4 04/13] mips: Add MIPS Warrior P5600 support

From: Thomas Bogendoerfer
Date: Fri May 22 2020 - 03:31:30 EST


On Thu, May 21, 2020 at 05:07:15PM +0300, Serge Semin wrote:
> This is a MIPS32 Release 5 based IP core with XPA, EVA, dual/quad issue
> exec pipes, MMU with two-levels TLB, UCA, MSA, MDU core level features
> and system level features like up to six P5600 calculation cores, CM2
> with L2 cache, IOCU/IOMMU (though might be unused depending on the
> system-specific IP core configuration), GIC, CPC, virtualisation module,
> eJTAG and PDtrace.
>
> As being MIPS32 Release 5 based core it provides all the features
> available by the CPU_MIPS32_R5 config, while adding a few more like
> UCA attribute support, availability of CPU-freq (by means of L2/CM
> clock ratio setting), EI/VI GIC modes detection at runtime.
>
> In addition to this if P5600 architecture is enabled modern GNU GCC
> provides a specific tuning for P5600 processors with respect to the
> classic MIPS32 Release 5. First of all branch-likely avoidance is
> activated only when the code is compiled with the speed optimization
> (avoidance is always enabled for the pure MIPS32 Release 5
> architecture). Secondly the madd/msub avoidance is enabled since
> madd/msub utilization isn't profitable due to overhead of getting the
> result out of the HI/LO registers. Multiply-accumulate instructions are
> activated and utilized together with the necessary code reorder when
> multiply-add/multiply-subtract statements are met. Finally load/store
> bonding is activated by default. All of these optimizations may make
> the code relatively faster than if just MIP32 release 5 architecture
> was requested.
>
> Co-developed-by: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> Cc: Paul Burton <paulburton@xxxxxxxxxx>
> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> ---
> arch/mips/Kconfig | 37 +++++++++++++++++++++++++++++-----
> arch/mips/Makefile | 1 +
> arch/mips/include/asm/module.h | 2 ++
> 3 files changed, 35 insertions(+), 5 deletions(-)

applied to mips-next.

Thomas.

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