The DBCN extension provides a Console Write Byte call. Implement function sbi_dbcn_write_byte to invoke it.
Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com --- arch/riscv/include/asm/sbi.h | 1 + arch/riscv/lib/sbi.c | 16 ++++++++++++++++ 2 files changed, 17 insertions(+)
diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h index 009a26885c..bf4c9af622 100644 --- a/arch/riscv/include/asm/sbi.h +++ b/arch/riscv/include/asm/sbi.h @@ -170,5 +170,6 @@ int sbi_get_mvendorid(long *mvendorid); int sbi_get_marchid(long *marchid); int sbi_get_mimpid(long *mimpid); void sbi_srst_reset(unsigned long type, unsigned long reason); +int sbi_dbcn_write_byte(unsigned char ch);
#endif diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c index 8724e3a460..55a3bc3b5c 100644 --- a/arch/riscv/lib/sbi.c +++ b/arch/riscv/lib/sbi.c @@ -204,6 +204,22 @@ void sbi_srst_reset(unsigned long type, unsigned long reason) 0, 0, 0, 0); }
+/** + * sbi_dbcn_write_byte() - write byte to debug console + * + * @ch: byte to be written + * Return: SBI error code (SBI_SUCCESS = 0 on success) + */ +int sbi_dbcn_write_byte(unsigned char ch) +{ + struct sbiret ret; + + ret = sbi_ecall(SBI_EXT_DBCN, + SBI_EXT_DBCN_CONSOLE_WRITE_BYTE, + ch, 0, 0, 0, 0, 0); + return ret.error; +} + #ifdef CONFIG_SBI_V01
/**