From 510e379c49ba8e0d90960d8cbc2ffb91091e229a Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Wed, 26 Sep 2018 06:55:21 -0700 Subject: [PATCH] riscv: Add QEMU virt board support This adds QEMU RISC-V 'virt' board target support, with the hope of helping people easily test U-Boot on RISC-V. The QEMU virt machine models a generic RISC-V virtual machine with support for the VirtIO standard networking and block storage devices. It has CLINT, PLIC, 16550A UART devices in addition to VirtIO and it also uses device-tree to pass configuration information to guest software. It implements RISC-V privileged architecture spec v1.10. Both 32-bit and 64-bit builds are supported. Support is pretty much preliminary, only booting to U-Boot shell with the UART driver on a single core. Booting Linux is not supported yet. Signed-off-by: Bin Meng Reviewed-by: Lukas Auer --- arch/riscv/Kconfig | 4 +++ arch/riscv/cpu/qemu/Makefile | 6 +++++ arch/riscv/cpu/qemu/cpu.c | 29 +++++++++++++++++++++ arch/riscv/cpu/qemu/dram.c | 17 ++++++++++++ board/emulation/qemu-riscv/Kconfig | 22 ++++++++++++++++ board/emulation/qemu-riscv/MAINTAINERS | 7 +++++ board/emulation/qemu-riscv/Makefile | 5 ++++ board/emulation/qemu-riscv/qemu-riscv.c | 23 +++++++++++++++++ configs/qemu-riscv32_defconfig | 6 +++++ configs/qemu-riscv64_defconfig | 7 +++++ doc/README.qemu-riscv | 46 +++++++++++++++++++++++++++++++++ include/configs/qemu-riscv.h | 21 +++++++++++++++ 12 files changed, 193 insertions(+) create mode 100644 arch/riscv/cpu/qemu/Makefile create mode 100644 arch/riscv/cpu/qemu/cpu.c create mode 100644 arch/riscv/cpu/qemu/dram.c create mode 100644 board/emulation/qemu-riscv/Kconfig create mode 100644 board/emulation/qemu-riscv/MAINTAINERS create mode 100644 board/emulation/qemu-riscv/Makefile create mode 100644 board/emulation/qemu-riscv/qemu-riscv.c create mode 100644 configs/qemu-riscv32_defconfig create mode 100644 configs/qemu-riscv64_defconfig create mode 100644 doc/README.qemu-riscv create mode 100644 include/configs/qemu-riscv.h diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 49f87de..168ca3d 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -11,9 +11,13 @@ choice config TARGET_AX25_AE350 bool "Support ax25-ae350" +config TARGET_QEMU_VIRT + bool "Support QEMU Virt Board" + endchoice source "board/AndesTech/ax25-ae350/Kconfig" +source "board/emulation/qemu-riscv/Kconfig" choice prompt "CPU selection" diff --git a/arch/riscv/cpu/qemu/Makefile b/arch/riscv/cpu/qemu/Makefile new file mode 100644 index 0000000..258e462 --- /dev/null +++ b/arch/riscv/cpu/qemu/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2018, Bin Meng + +obj-y += dram.o +obj-y += cpu.o diff --git a/arch/riscv/cpu/qemu/cpu.c b/arch/riscv/cpu/qemu/cpu.c new file mode 100644 index 0000000..a064639 --- /dev/null +++ b/arch/riscv/cpu/qemu/cpu.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2018, Bin Meng + */ + +#include +#include + +/* + * cleanup_before_linux() is called just before we call linux + * it prepares the processor for linux + * + * we disable interrupt and caches. + */ +int cleanup_before_linux(void) +{ + disable_interrupts(); + + /* turn off I/D-cache */ + + return 0; +} + +int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + printf("reset unsupported yet\n"); + + return 0; +} diff --git a/arch/riscv/cpu/qemu/dram.c b/arch/riscv/cpu/qemu/dram.c new file mode 100644 index 0000000..84d87d2 --- /dev/null +++ b/arch/riscv/cpu/qemu/dram.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2018, Bin Meng + */ + +#include +#include + +int dram_init(void) +{ + return fdtdec_setup_mem_size_base(); +} + +int dram_init_banksize(void) +{ + return fdtdec_setup_memory_banksize(); +} diff --git a/board/emulation/qemu-riscv/Kconfig b/board/emulation/qemu-riscv/Kconfig new file mode 100644 index 0000000..af23363 --- /dev/null +++ b/board/emulation/qemu-riscv/Kconfig @@ -0,0 +1,22 @@ +if TARGET_QEMU_VIRT + +config SYS_BOARD + default "qemu-riscv" + +config SYS_VENDOR + default "emulation" + +config SYS_CPU + default "qemu" + +config SYS_CONFIG_NAME + default "qemu-riscv" + +config SYS_TEXT_BASE + default 0x80000000 + +config BOARD_SPECIFIC_OPTIONS # dummy + def_bool y + imply SYS_NS16550 + +endif diff --git a/board/emulation/qemu-riscv/MAINTAINERS b/board/emulation/qemu-riscv/MAINTAINERS new file mode 100644 index 0000000..3c6eb4f --- /dev/null +++ b/board/emulation/qemu-riscv/MAINTAINERS @@ -0,0 +1,7 @@ +QEMU RISC-V 'VIRT' BOARD +M: Bin Meng +S: Maintained +F: board/emulation/qemu-riscv/ +F: include/configs/qemu-riscv.h +F: configs/qemu-riscv32_defconfig +F: configs/qemu-riscv64_defconfig diff --git a/board/emulation/qemu-riscv/Makefile b/board/emulation/qemu-riscv/Makefile new file mode 100644 index 0000000..3f29b90 --- /dev/null +++ b/board/emulation/qemu-riscv/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2018, Bin Meng + +obj-y += qemu-riscv.o diff --git a/board/emulation/qemu-riscv/qemu-riscv.c b/board/emulation/qemu-riscv/qemu-riscv.c new file mode 100644 index 0000000..041e716 --- /dev/null +++ b/board/emulation/qemu-riscv/qemu-riscv.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2018, Bin Meng + */ + +#include +#include + +#define MROM_FDT_ADDR 0x1020 + +int board_init(void) +{ + return 0; +} + +void *board_fdt_blob_setup(void) +{ + /* + * QEMU loads a generated DTB for us immediately + * after the reset vectors in the MROM + */ + return (void *)MROM_FDT_ADDR; +} diff --git a/configs/qemu-riscv32_defconfig b/configs/qemu-riscv32_defconfig new file mode 100644 index 0000000..ff1fb1f --- /dev/null +++ b/configs/qemu-riscv32_defconfig @@ -0,0 +1,6 @@ +CONFIG_RISCV=y +CONFIG_TARGET_QEMU_VIRT=y +CONFIG_NR_DRAM_BANKS=1 +CONFIG_DISPLAY_CPUINFO=y +CONFIG_DISPLAY_BOARDINFO=y +CONFIG_OF_BOARD=y diff --git a/configs/qemu-riscv64_defconfig b/configs/qemu-riscv64_defconfig new file mode 100644 index 0000000..d6c1a5d --- /dev/null +++ b/configs/qemu-riscv64_defconfig @@ -0,0 +1,7 @@ +CONFIG_RISCV=y +CONFIG_TARGET_QEMU_VIRT=y +CONFIG_CPU_RISCV_64=y +CONFIG_NR_DRAM_BANKS=1 +CONFIG_DISPLAY_CPUINFO=y +CONFIG_DISPLAY_BOARDINFO=y +CONFIG_OF_BOARD=y diff --git a/doc/README.qemu-riscv b/doc/README.qemu-riscv new file mode 100644 index 0000000..e2e4804 --- /dev/null +++ b/doc/README.qemu-riscv @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2018, Bin Meng + +U-Boot on QEMU's 'virt' machine on RISC-V +========================================= + +QEMU for RISC-V supports a special 'virt' machine designed for emulation and +virtualization purposes. This document describes how to run U-Boot under it. +Both 32-bit 64-bit targets are supported. + +The QEMU virt machine models a generic RISC-V virtual machine with support for +the VirtIO standard networking and block storage devices. It has CLINT, PLIC, +16550A UART devices in addition to VirtIO and it also uses device-tree to pass +configuration information to guest software. It implements RISC-V privileged +architecture spec v1.10. + +Building U-Boot +--------------- +Set the CROSS_COMPILE environment variable as usual, and run: + +- For 32-bit RISC-V: + make qemu-riscv32_defconfig + make + +- For 64-bit RISC-V: + make qemu-riscv64_defconfig + make + +Running U-Boot +-------------- +The minimal QEMU command line to get U-Boot up and running is: + +- For 32-bit RISC-V: + qemu-system-riscv32 -nographic -machine virt -kernel u-boot + +- For 64-bit RISC-V: + qemu-system-riscv64 -nographic -machine virt -kernel u-boot + +The commands above create targets with 128MiB memory by default. +A freely configurable amount of RAM can be created via the '-m' +parameter. For example, '-m 2G' creates 2GiB memory for the target, +and the memory node in the embedded DTB created by QEMU reflects +the new setting. + +These have been tested in QEMU 3.0.0. diff --git a/include/configs/qemu-riscv.h b/include/configs/qemu-riscv.h new file mode 100644 index 0000000..d279c23 --- /dev/null +++ b/include/configs/qemu-riscv.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (C) 2018, Bin Meng + */ + +#ifndef __CONFIG_H +#define __CONFIG_H + +#include + +#define CONFIG_SYS_SDRAM_BASE 0x80000000 +#define CONFIG_SYS_INIT_SP_ADDR (CONFIG_SYS_SDRAM_BASE + SZ_2M) + +#define CONFIG_SYS_LOAD_ADDR (CONFIG_SYS_SDRAM_BASE + SZ_2M) + +#define CONFIG_SYS_MALLOC_LEN SZ_8M + +/* Environment options */ +#define CONFIG_ENV_SIZE SZ_4K + +#endif /* __CONFIG_H */