Unverified Commit 88ead68e authored by Atish Patra's avatar Atish Patra Committed by Palmer Dabbelt
Browse files

tty: Add SBI debug console support to HVC SBI driver 



RISC-V SBI specification supports advanced debug console
support via SBI DBCN extension.

Extend the HVC SBI driver to support it.

Signed-off-by: default avatarAtish Patra <atishp@rivosinc.com>
Signed-off-by: default avatarAnup Patel <apatel@ventanamicro.com>
Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20231124070905.1043092-5-apatel@ventanamicro.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent c77bf360

drivers/tty/hvc/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP 


config HVC_RISCV_SBI

	bool "RISC-V SBI console support"

	depends on RISCV_SBI_V01

	depends on RISCV_SBI

	select HVC_DRIVER

	help

	  This enables support for console output via RISC-V SBI calls, which

drivers/tty/hvc/hvc_riscv_sbi.c

+30 −7
Original line number Diff line number Diff line
@@ -39,21 +39,44 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count) 
	return i;

}



static const struct hv_ops hvc_sbi_ops = {

static const struct hv_ops hvc_sbi_v01_ops = {

	.get_chars = hvc_sbi_tty_get,

	.put_chars = hvc_sbi_tty_put,

};



static int __init hvc_sbi_init(void)

static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)

{

	return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));

	return sbi_debug_console_write(buf, count);

}

device_initcall(hvc_sbi_init);



static int __init hvc_sbi_console_init(void)

static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)

{

	hvc_instantiate(0, 0, &hvc_sbi_ops);

	return sbi_debug_console_read(buf, count);

}



static const struct hv_ops hvc_sbi_dbcn_ops = {

	.put_chars = hvc_sbi_dbcn_tty_put,

	.get_chars = hvc_sbi_dbcn_tty_get,

};



static int __init hvc_sbi_init(void)

{

	int err;



	if (sbi_debug_console_available) {

		err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_dbcn_ops, 256));

		if (err)

			return err;

		hvc_instantiate(0, 0, &hvc_sbi_dbcn_ops);

	} else if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) {

		err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_v01_ops, 256));

		if (err)

			return err;

		hvc_instantiate(0, 0, &hvc_sbi_v01_ops);

	} else {

		return -ENODEV;

	}



	return 0;

}

console_initcall(hvc_sbi_console_init);
 
device_initcall(hvc_sbi_init);