diff options
| author | Bin Meng <bmeng.cn@gmail.com> | 2018-12-12 06:12:38 -0800 |
|---|---|---|
| committer | Andes <uboot@andestech.com> | 2018-12-18 09:56:27 +0800 |
| commit | aef59e5cc450f403478f799bbb0f0647ff28a3c3 (patch) | |
| tree | a8dd18c0e493e9614a4e7331dd832d945ad963de /arch/riscv/cpu | |
| parent | 3967156464282df161f5e4be40999dae47adf799 (diff) | |
riscv: Update supports_extension() to use desc from cpu driver
This updates supports_extension() implementation to use the desc
string from the cpu driver whenever possible, which avoids the
reading of misa CSR for S-mode U-Boot.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
Diffstat (limited to 'arch/riscv/cpu')
| -rw-r--r-- | arch/riscv/cpu/cpu.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c index d3c59da34b..fc7c9b3751 100644 --- a/arch/riscv/cpu/cpu.c +++ b/arch/riscv/cpu/cpu.c @@ -5,8 +5,10 @@ #include <common.h> #include <cpu.h> +#include <dm.h> #include <log.h> #include <asm/csr.h> +#include <dm/uclass-internal.h> /* * prior_stage_fdt_address must be stored in the data section since it is used @@ -16,7 +18,31 @@ phys_addr_t prior_stage_fdt_address __attribute__((section(".data"))); static inline bool supports_extension(char ext) { +#ifdef CONFIG_CPU + struct udevice *dev; + char desc[32]; + + uclass_find_first_device(UCLASS_CPU, &dev); + if (!dev) { + debug("unable to find the RISC-V cpu device\n"); + return false; + } + if (!cpu_get_desc(dev, desc, sizeof(desc))) { + /* skip the first 4 characters (rv32|rv64) */ + if (strchr(desc + 4, ext)) + return true; + } + + return false; +#else /* !CONFIG_CPU */ +#ifdef CONFIG_RISCV_MMODE return csr_read(misa) & (1 << (ext - 'a')); +#else /* !CONFIG_RISCV_MMODE */ +#warning "There is no way to determine the available extensions in S-mode." +#warning "Please convert your board to use the RISC-V CPU driver." + return false; +#endif /* CONFIG_RISCV_MMODE */ +#endif /* CONFIG_CPU */ } static int riscv_cpu_probe(void) |