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

Anup Patel
2021-06-07T03:45:22Z

> -----Original Message-----
> From: guoren@kernel.org <guoren@kernel.org>
> Sent: 06 June 2021 14:34
> To: guoren@kernel.org; Anup Patel <Anup.Patel@wdc.com>;
> palmerdabbelt@google.com; arnd@arndb.de; wens@csie.org;
> maxime@cerno.tech; drew@beagleboard.org; liush@allwinnertech.com;
> lazyparser@gmail.com; wefu@redhat.com
> Cc: linux-riscv@lists.infradead.org; linux-kernel@vger.kernel.org; linux-
> arch@vger.kernel.org; linux-sunxi@lists.linux.dev; Guo Ren
> <guoren@linux.alibaba.com>
> Subject: [RFC PATCH v2 00/11] riscv: Add DMA_COHERENT support for
> Allwinner D1
>
> 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]
>
> 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

The series cover letter says DMA_COHERENT support but
it is doing lot of stuff not related to DMA.

Please keep the first three patches separate. They belong
to your ASID series.

I also dislike the fact that you are continuously sending
SBI DMA sync patches without any discussion on the
UnixPlatform mailing list for SBI spec changes.

Regards,
Anup

>
> 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
>
> --
> 2.7.4