On 9/4/23 11:30, Chanho Park wrote:
Hi,
-----Original Message-----
From: U-Boot <u-boot-boun...@lists.denx.de> On Behalf Of Heinrich
Schuchardt
Sent: Saturday, August 19, 2023 10:13 PM
To: Rick Chen <r...@andestech.com>; Leo <ycli...@andestech.com>
Cc: Bin Meng <bmeng...@gmail.com>; Anup Patel <apa...@ventanamicro.com>;
u-boot@lists.denx.de; Heinrich Schuchardt
<heinrich.schucha...@canonical.com>
Subject: [PATCH 2/2] risc-v: implement DBCN based debug console
Use the DBCN SBI extension to implement a debug console.
Make it the default for S-mode RISC-V.
Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com>
---
drivers/serial/Kconfig | 3 ++-
drivers/serial/serial_sbi.c | 19 +++++++++++++++++++
2 files changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index
a1e089962a..8421c5c047 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -218,6 +218,7 @@ config DEBUG_UART
choice
prompt "Select which UART will provide the debug UART"
depends on DEBUG_UART
+ default DEBUG_SBI_CONSOLE if RISCV_SMODE
default DEBUG_UART_NS16550
config DEBUG_UART_ALTERA_JTAGUART
@@ -289,7 +290,7 @@ config DEBUG_EFI_CONSOLE
config DEBUG_SBI_CONSOLE
bool "SBI"
- depends on SBI_V01
+ depends on RISCV_SMODE
help
Select this to enable a debug console which calls back to SBI to
output to the console. This can be useful for early debugging of
diff --git a/drivers/serial/serial_sbi.c b/drivers/serial/serial_sbi.c
index b9f35ed36e..093c7309d3 100644
--- a/drivers/serial/serial_sbi.c
+++ b/drivers/serial/serial_sbi.c
@@ -3,6 +3,8 @@
#include <debug_uart.h>
#include <asm/sbi.h>
+#ifdef CONFIG_SBI_V01
+
static inline void _debug_uart_init(void) { } @@ -13,4 +15,21 @@ static
inline void _debug_uart_putc(int c)
sbi_console_putchar(c);
}
+#else
+
+static int sbi_dbcn_available;
+
+static inline void _debug_uart_init(void) {
+ sbi_dbcn_available = sbi_probe_extension(SBI_EXT_DBCN);
+}
+
+static inline void _debug_uart_putc(int ch) {
+ if (sbi_dbcn_available)
+ sbi_dbcn_write_byte(ch);
+}
+
+#endif
+
DEBUG_UART_FUNCS
--
2.40.1
I've got below error when I tried to build it with VisionFive2 board
configuration(starfive_visionfive2_defconfig).
To test this patch, I enabled CONFIG_DEBUG_SBI_CONSOLE. Seems like spl also
includes the driver when DEBUG_SBI_CONSOLE is enabled.
Do I need to do any more configurations to test this?
LD spl/u-boot-spl
riscv64-unknown-linux-gnu-ld.bfd: drivers/serial/serial_sbi.o: in function
`_debug_uart_putc':
/data/risc-v/vf2/mainline/u-boot/drivers/serial/serial_sbi.c:30: undefined
reference to `sbi_dbcn_write_byte'
riscv64-unknown-linux-gnu-ld.bfd:
/data/risc-v/vf2/mainline/u-boot/drivers/serial/serial_sbi.c:30: undefined
reference to `sbi_dbcn_write_byte'
riscv64-unknown-linux-gnu-ld.bfd: drivers/serial/serial_sbi.o: in function
`_debug_uart_init':
/data/risc-v/vf2/mainline/u-boot/drivers/serial/serial_sbi.c:24: undefined
reference to `sbi_probe_extension'
make[2]: *** [/data/risc-v/vf2/mainline/u-boot/scripts/Makefile.spl:527:
spl/u-boot-spl] Error 1
Best Regards,
Chanho Park
Hello Chanho,
thanks for reporting the issue. SBI is not available in M-mode. We need
a check in the driver like
if (!CONFIG_IS_ENABLED(RISCV_MMODE))
I will send a new version of the series.
Best regards
Heinrich
