RISC-V

Today, I would disclose RISC-V. Let's save my word and dive into it directly. As of today, December 18, 2023, MOST of RISC-V chips are designed and manufactured by Chinese companies.

1. Related Companies

• Andes Tech - headquarter in Taiwan
• SiFive - headquarter in Santa Clara, USA
• StarFive - headquarter in Shanghai, China
• Canaan - headquarter in Beijing, China
• Microchip - headquarter in Arizona, USA
• All Winner Tech - headquarter in Zhuhai, China
• T-Head - headquarter in Hangzhou, China. An Alibaba company

2. U-Boot

➜  u-boot git:(master) ✗ ls arch
arc  arm  Kconfig  Kconfig.nxp  m68k  microblaze  mips  nios2  powerpc  riscv  sandbox  sh  u-boot-elf.lds  x86  xtensa
➜  u-boot git:(master) ✗ cd arch/riscv 
➜  riscv git:(master) ✗ ls cpu
andesv5     cpu.c  cpu.su  fu740    jh7110    mtrap.o  start.o  u-boot.lds
built-in.o  cpu.o  fu540   generic  Makefile  mtrap.S  start.S  u-boot-spl.lds
➜  riscv git:(master) ✗ ls dts
ae350_32.dts                         hifive-unmatched-a00.dts                  mpfs-icicle-kit.dts
ae350_64.dts                         hifive-unmatched-a00-u-boot.dtsi          mpfs-icicle-kit-fabric.dtsi
ae350-u-boot.dtsi                    jh7110.dtsi                               mpfs-icicle-kit-u-boot.dtsi
binman.dtsi                          jh7110-starfive-visionfive-2.dtb          openpiton-riscv64.dts
fu540-c000.dtsi                      jh7110-starfive-visionfive-2.dts          qemu-virt32.dts
fu540-c000-u-boot.dtsi               jh7110-starfive-visionfive-2.dtsi         qemu-virt64.dts
fu540-hifive-unleashed-a00-ddr.dtsi  jh7110-starfive-visionfive-2-u-boot.dtsi  sunxi-d1s-t113.dtsi
fu740-c000.dtsi                      jh7110-u-boot.dtsi                        sunxi-d1-t113.dtsi
fu740-c000-u-boot.dtsi               k210.dtsi                                 th1520.dtsi
fu740-hifive-unmatched-a00-ddr.dtsi  k210-maix-bit.dts                         th1520-lichee-module-4a.dtsi
hifive-unleashed-a00.dts             Makefile                                  th1520-lichee-pi-4a.dts
hifive-unleashed-a00-u-boot.dtsi     mpfs.dtsi
➜  riscv git:(master) ✗ 

2.1 CPU

Let's simple analyze all 5 folders under subfolder cpu.

• andesv5 - designed by Andes Tech
• fu540 - designed by SiFive
• fu740 - designed by SiFive
• jh7110 - designed by StarFive
• generic

2.2 DTS

Let's further analyze all device trees under subfolder dts.

• ae350 - designed by Andes Tech
• fu540 - designed by SiFive
• fu740 - designed by SiFive
• hifive - designed by SiFive
• jh7110 - designed by StarFive
• k210 - designed by Canaan
• mpfs - designed by Microchip
• openpiton - designed by Princeton OpenPiton
• sunxi - designed by All Winner Tech
• th1520 - designed by T-Head, it's just Xuantie C910

3. Linux Kernel

➜  linux ls arch
alpha  arm    csky     ia64     loongarch  microblaze  nios2     parisc   riscv  sh     um   xtensa
arc    arm64  hexagon  Kconfig  m68k       mips        openrisc  powerpc  s390   sparc  x86
➜  linux cd arch/riscv 
➜  riscv ls configs
32-bit.config  defconfig             nommu_k210_sdcard_defconfig  rv32_defconfig
64-bit.config  nommu_k210_defconfig  nommu_virt_defconfig
➜  riscv ls boot/dts 
allwinner  canaan  Makefile  microchip  renesas  sifive  starfive  thead

3.1 DTS

Again, let's analyze all 5 folders under subfolder dts.

• allwinner - All Winner Tech
• canaan - Canaan
• microchip - Microchip
• renesas - Renesas
• sifive - SiFive
• starfive - StarFive
• thead - T-Head

By the way: recent Arduino UNO R4 uses a Renesas RA4M1, a 32-bit Arm® Cortex®-M4 MCU.

Conclusion: MOST of recent RISC-V chips are supported, designed, and manufactured by China.