Re: [RFC PATCH v2 00/11] riscv: Add DMA_COHERENT support for Allwinner D1

["Jernej Škrabec" <jernej.skrabec@gmail.com>]

Hi!

Dne nedelja, 06. junij 2021 ob 11:03:55 CEST je guoren@kernel.org napisal(a):
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> The RISC-V ISA doesn't yet specify how to query or modify PMAs, so let
> vendors define the custom properties of memory regions in PTE.
> 
> This patchset helps SOC vendors to support their own custom interconnect
> coherent solution with PTE attributes.
> 
> For example, allwinner D1[1] uses T-HEAD C906 as main processor, C906 has
> two modes in MMU:
>  - Compatible mode, the same as the definitions in spec.
>  - Enhanced mode, add custom DMA_COHERENT attribute bits in PTE which
>    not mentioned in spec.
> 
> Allwinner D1 needs the enhanced mode to support the DMA type device with
> non-coherent interconnect in its SOC. C906 uses BITS(63 - 59) as custom
> attribute bits in PTE.
> 
> The patchset contain 4 parts (asid, pgtable, cmo, soc) which have been
> tested on D1:
>  - asid: T-HEAD C906 of D1 contains full asid hw facilities which has no
>    conflict with RISC-V spec, and hope these patches soon could be
>    approved.
>  - pgtable: Using a image-hdr to pass vendor specific information and
>    setup custom PTE attributes in a global struct variable during boot
>    stage. Also it needs define custom protection_map in linux/mm.
>  - cmo: We need deal with dma_sync & icache_sync & __vdso_icache_sync.
>    In this patchset, I just show you how T-HEAD C9xx work, and seems Atish
>    is working for the DMA infrustructure, please let me know the idea.
>  - soc: Add allwinner gmac driver & dts & Kconfig for sunxi test.
> 
> The patchset could work with linux-5.13-rc4, here is the steps for D1:
>  - Download linux-5.13-rc4 and apply the patchset
>  - make ARCH=riscv CROSS_COMPILE=riscv64-linux- defconfig
>  - make ARCH=riscv CROSS_COMPILE=riscv64-linux- Image modules dtbs
>  - mkimage -A riscv -O linux -T kernel -C none -a 0x00200000 -e 0x00200000
> -n Linux -d arch/riscv/boot/Image uImage - Download newest opensbi [2],
> build with [3], and get fw_dynamic.bin - Copy uImage, fw_dynamic.bin,
> allwinner-d1-nezha-kit.dtb into boot partition of TF card.
>  - Plugin the TF card and power on D1.
> 
> Link: https://linux-sunxi.org/D1 [1]
> Link: https://github.com/riscv/opensbi branch:master [2]
> Link:
> https://github.com/riscv/opensbi/blob/master/docs/platform/thead-c9xx.md
> [3]
> 

Some patches are marked with v2 and some V5. It's very confusing. Mark them 
with same version in next revision.

Best regards,
Jernej

> Changes since v1:
>  - Rebase on linux-5.13-rc4
>  - Support defconfig for different PTE attributes
>  - Support C906 icache_sync
>  - Add Allwinner D1 dts & Kconfig & gmac for testing
>  - Add asid optimization for D1 usage
> 
> Guo Ren (10):
>   riscv: asid: Use global mappings for kernel pages
>   riscv: asid: Add ASID-based tlbflushing methods
>   riscv: asid: Optimize tlbflush coding convention
>   riscv: pgtable: Fixup _PAGE_CHG_MASK usage
>   riscv: pgtable: Add custom protection_map init
>   riscv: pgtable: Add DMA_COHERENT with custom PTE attributes
>   riscv: cmo: Add dma-noncoherency support
>   riscv: cmo: Add vendor custom icache sync
>   riscv: soc: Initial DTS for Allwinner D1 NeZha board
>   riscv: soc: Add Allwinner SoC kconfig option
> 
> liush (1):
>   riscv: soc: Allwinner D1 GMAC driver only for temp use
> 
>  arch/riscv/Kconfig                                 |    9 +
>  arch/riscv/Kconfig.socs                            |   12 +
>  arch/riscv/boot/dts/Makefile                       |    1 +
>  arch/riscv/boot/dts/allwinner/Makefile             |    2 +
>  .../boot/dts/allwinner/allwinner-d1-nezha-kit.dts  |   29 +
>  arch/riscv/boot/dts/allwinner/allwinner-d1.dtsi    |  100 +
>  arch/riscv/configs/defconfig                       |    1 +
>  arch/riscv/include/asm/cacheflush.h                |   48 +-
>  arch/riscv/include/asm/mmu_context.h               |    2 +
>  arch/riscv/include/asm/pgtable-64.h                |    8 +-
>  arch/riscv/include/asm/pgtable-bits.h              |   20 +-
>  arch/riscv/include/asm/pgtable.h                   |   44 +-
>  arch/riscv/include/asm/sbi.h                       |   15 +
>  arch/riscv/include/asm/soc.h                       |    1 +
>  arch/riscv/include/asm/tlbflush.h                  |   22 +
>  arch/riscv/include/asm/vendorid_list.h             |    1 +
>  arch/riscv/kernel/sbi.c                            |   19 +
>  arch/riscv/kernel/soc.c                            |   22 +
>  arch/riscv/kernel/vdso/flush_icache.S              |   33 +-
>  arch/riscv/mm/Makefile                             |    1 +
>  arch/riscv/mm/cacheflush.c                         |    3 +-
>  arch/riscv/mm/context.c                            |    2 +-
>  arch/riscv/mm/dma-mapping.c                        |   53 +
>  arch/riscv/mm/init.c                               |   26 +
>  arch/riscv/mm/tlbflush.c                           |   57 +-
>  drivers/net/ethernet/Kconfig                       |    1 +
>  drivers/net/ethernet/Makefile                      |    1 +
>  drivers/net/ethernet/allwinnertmp/Kconfig          |   17 +
>  drivers/net/ethernet/allwinnertmp/Makefile         |    7 +
>  drivers/net/ethernet/allwinnertmp/sunxi-gmac-ops.c |  690 ++++++
>  drivers/net/ethernet/allwinnertmp/sunxi-gmac.c     | 2240
> ++++++++++++++++++++ drivers/net/ethernet/allwinnertmp/sunxi-gmac.h     | 
> 258 +++
>  drivers/net/phy/realtek.c                          |    2 +-
>  mm/mmap.c                                          |    4 +
>  34 files changed, 3714 insertions(+), 37 deletions(-)
>  create mode 100644 arch/riscv/boot/dts/allwinner/Makefile
>  create mode 100644 arch/riscv/boot/dts/allwinner/allwinner-d1-nezha-kit.dts
> create mode 100644 arch/riscv/boot/dts/allwinner/allwinner-d1.dtsi create
> mode 100644 arch/riscv/mm/dma-mapping.c
>  create mode 100644 drivers/net/ethernet/allwinnertmp/Kconfig
>  create mode 100644 drivers/net/ethernet/allwinnertmp/Makefile
>  create mode 100644 drivers/net/ethernet/allwinnertmp/sunxi-gmac-ops.c
>  create mode 100644 drivers/net/ethernet/allwinnertmp/sunxi-gmac.c
>  create mode 100644 drivers/net/ethernet/allwinnertmp/sunxi-gmac.h