- This patch supports debug serial and console from SBI syscall.
Signed-off-by: Kongou Hikari <hik...@nucleisys.com>
---
drivers/serial/Kconfig | 17 +++++
drivers/serial/Makefile | 1 +
drivers/serial/serial_riscv_sbi.c | 104 ++++++++++++++++++++++++++++++
3 files changed, 122 insertions(+)
create mode 100644 drivers/serial/serial_riscv_sbi.c
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 90e3983170..60dcf9bc9a 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -388,12 +388,20 @@ config DEBUG_UART_MTK
driver will be available until the real driver model serial is
running.
+
+config DEBUG_UART_RISCV_SBI
+ bool "RISC-V SBI CONSOLE"
+ depends on RISCV_SBI_CONSOLE
+ help
+ Select this to enable a debug UART using RISC-V SBI console driver.
+
endchoice
config DEBUG_UART_BASE
hex "Base address of UART"
depends on DEBUG_UART
default 0 if DEBUG_UART_SANDBOX
+ default 0 if DEBUG_UART_RISCV_SBI
help
This is the base address of your UART for memory-mapped UARTs.
@@ -404,6 +412,7 @@ config DEBUG_UART_CLOCK
int "UART input clock"
depends on DEBUG_UART
default 0 if DEBUG_UART_SANDBOX
+ default 0 if DEBUG_UART_RISCV_SBI
help
The UART input clock determines the speed of the internal UART
circuitry. The baud rate is derived from this by dividing the input
@@ -481,6 +490,14 @@ config ALTERA_JTAG_UART_BYPASS
output will wait forever until a JTAG terminal is connected. If you
not are sure, say Y.
+config RISCV_SBI_CONSOLE
+ bool "RISC-V SBI console support"
+ depends on RISCV
+ help
+ This enables support for console via RISC-V SBI calls.
+
+ If you don't know what do to here, say Y.
+
config ALTERA_UART
bool "Altera UART support"
depends on DM_SERIAL
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index e4a92bbbb7..15b2a3ea6f 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -46,6 +46,7 @@ obj-$(CONFIG_MXC_UART) += serial_mxc.o
obj-$(CONFIG_PXA_SERIAL) += serial_pxa.o
obj-$(CONFIG_MESON_SERIAL) += serial_meson.o
obj-$(CONFIG_INTEL_MID_SERIAL) += serial_intel_mid.o
+obj-$(CONFIG_RISCV_SBI_CONSOLE) += serial_riscv_sbi.o
ifdef CONFIG_SPL_BUILD
obj-$(CONFIG_ROCKCHIP_SERIAL) += serial_rockchip.o
endif
diff --git a/drivers/serial/serial_riscv_sbi.c
b/drivers/serial/serial_riscv_sbi.c
new file mode 100644
index 0000000000..add11be04e
--- /dev/null
+++ b/drivers/serial/serial_riscv_sbi.c
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2008 David Gibson, IBM Corporation
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2020 Nuclei System Technologies
+ * Copyright (C) 2020 Ruigang Wan <rg...@nucleisys.com>
+ */
+
+#include <common.h>
+#include <serial.h>
+#include <errno.h>
+#include <dm.h>
+#include <fdtdec.h>
+
+#include <asm/sbi.h>
+
+
+#ifdef CONFIG_DEBUG_UART_RISCV_SBI
+
+#include <debug_uart.h>
+
+
+static inline void _debug_uart_init(void)
+{
+ //Nothing
+}
+
+static inline void _debug_uart_putc(int ch)
+{
+ sbi_console_putchar(ch);
+}
+
+DEBUG_UART_FUNCS
+
+#endif
+
+static int sbi_tty_pending_char = -1;
+
+static int sbi_tty_put(struct udevice *dev, const char ch)
+{
+
+ sbi_console_putchar(ch);
+
+ return 0;
+}
+
+static int sbi_tty_get(struct udevice *dev)
+{
+ int c;
+ if (sbi_tty_pending_char != -1)
+ {
+ c = sbi_tty_pending_char;
+ sbi_tty_pending_char = -1;
+ }
+ else
+ {
+ c = sbi_console_getchar();
+ if (c < 0)
+ return -EAGAIN;
+ }
+
+ return c;
+}
+
+static int sbi_tty_setbrg(struct udevice *dev, int baudrate)
+{
+ return 0;
+}
+
+static int sbi_tty_pending(struct udevice *dev, bool input)
+{
+ int c;
+ if (input)
+ {
+ if (sbi_tty_pending_char != -1)
+ return 1;
+
+ c = sbi_console_getchar();
+ if(c < 0)
+ return 0;
+ sbi_tty_pending_char = c;
+ return 1;
+ }
+ return 0;
+}
+
+static const struct udevice_id serial_riscv_sbi_ids[] = {
+ { .compatible = "sbi,console" },
+ { }
+};
+
+const struct dm_serial_ops serial_riscv_sbi_ops = {
+ .putc = sbi_tty_put,
+ .pending = sbi_tty_pending,
+ .getc = sbi_tty_get,
+ .setbrg = sbi_tty_setbrg,
+};
+
+U_BOOT_DRIVER(serial_riscv_sbi) = {
+ .name = "serial_riscv_sbi",
+ .id = UCLASS_SERIAL,
+ .of_match = serial_riscv_sbi_ids,
+ .ops = &serial_riscv_sbi_ops,
+};
--
2.17.1
