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[PATCH v4 3/5] tty/serial: Add RISC-V SBI debug console based earlycon

Anup Patel posted 5 patches 2 years, 1 month ago
There is a newer version of this series
[PATCH v4 3/5] tty/serial: Add RISC-V SBI debug console based earlycon
Posted by Anup Patel 2 years, 1 month ago 
We extend the existing RISC-V SBI earlycon support to use the new
RISC-V SBI debug console extension.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 drivers/tty/serial/Kconfig              |  2 +-
 drivers/tty/serial/earlycon-riscv-sbi.c | 24 ++++++++++++++++++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 732c893c8d16..1f2594b8ab9d 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -87,7 +87,7 @@ config SERIAL_EARLYCON_SEMIHOST
 
 config SERIAL_EARLYCON_RISCV_SBI
 	bool "Early console using RISC-V SBI"
-	depends on RISCV_SBI_V01
+	depends on RISCV_SBI
 	select SERIAL_CORE
 	select SERIAL_CORE_CONSOLE
 	select SERIAL_EARLYCON
diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c
index 27afb0b74ea7..5351e1e31f45 100644
--- a/drivers/tty/serial/earlycon-riscv-sbi.c
+++ b/drivers/tty/serial/earlycon-riscv-sbi.c
@@ -15,17 +15,33 @@ static void sbi_putc(struct uart_port *port, unsigned char c)
 	sbi_console_putchar(c);
 }
 
-static void sbi_console_write(struct console *con,
-			      const char *s, unsigned n)
+static void sbi_0_1_console_write(struct console *con,
+				  const char *s, unsigned int n)
 {
 	struct earlycon_device *dev = con->data;
 	uart_console_write(&dev->port, s, n, sbi_putc);
 }
 
+static void sbi_dbcn_console_write(struct console *con,
+				   const char *s, unsigned int n)
+{
+	sbi_debug_console_write(n, __pa(s));
+}
+
 static int __init early_sbi_setup(struct earlycon_device *device,
 				  const char *opt)
 {
-	device->con->write = sbi_console_write;
-	return 0;
+	int ret = 0;
+
+	if (sbi_debug_console_available) {
+		device->con->write = sbi_dbcn_console_write;
+	} else {
+		if (IS_ENABLED(CONFIG_RISCV_SBI_V01))
+			device->con->write = sbi_0_1_console_write;
+		else
+			ret = -ENODEV;
+	}
+
+	return ret;
 }
 EARLYCON_DECLARE(sbi, early_sbi_setup);
-- 
2.34.1
Re: [PATCH v4 3/5] tty/serial: Add RISC-V SBI debug console based earlycon
Posted by Samuel Holland 2 years, 1 month ago 
Hi Anup,

On 2023-11-17 9:38 PM, Anup Patel wrote:
> We extend the existing RISC-V SBI earlycon support to use the new
> RISC-V SBI debug console extension.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> ---
>  drivers/tty/serial/Kconfig              |  2 +-
>  drivers/tty/serial/earlycon-riscv-sbi.c | 24 ++++++++++++++++++++----
>  2 files changed, 21 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> index 732c893c8d16..1f2594b8ab9d 100644
> --- a/drivers/tty/serial/Kconfig
> +++ b/drivers/tty/serial/Kconfig
> @@ -87,7 +87,7 @@ config SERIAL_EARLYCON_SEMIHOST
>  
>  config SERIAL_EARLYCON_RISCV_SBI
>  	bool "Early console using RISC-V SBI"
> -	depends on RISCV_SBI_V01
> +	depends on RISCV_SBI
>  	select SERIAL_CORE
>  	select SERIAL_CORE_CONSOLE
>  	select SERIAL_EARLYCON
> diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c
> index 27afb0b74ea7..5351e1e31f45 100644
> --- a/drivers/tty/serial/earlycon-riscv-sbi.c
> +++ b/drivers/tty/serial/earlycon-riscv-sbi.c
> @@ -15,17 +15,33 @@ static void sbi_putc(struct uart_port *port, unsigned char c)
>  	sbi_console_putchar(c);
>  }
>  
> -static void sbi_console_write(struct console *con,
> -			      const char *s, unsigned n)
> +static void sbi_0_1_console_write(struct console *con,
> +				  const char *s, unsigned int n)
>  {
>  	struct earlycon_device *dev = con->data;
>  	uart_console_write(&dev->port, s, n, sbi_putc);
>  }
>  
> +static void sbi_dbcn_console_write(struct console *con,
> +				   const char *s, unsigned int n)
> +{
> +	sbi_debug_console_write(n, __pa(s));

This only works for strings in the linear mapping or the kernel mapping (not
vmalloc, which includes the stack). So I don't think we can use __pa() here.

> +}
> +
>  static int __init early_sbi_setup(struct earlycon_device *device,
>  				  const char *opt)
>  {
> -	device->con->write = sbi_console_write;
> -	return 0;
> +	int ret = 0;
> +
> +	if (sbi_debug_console_available) {
> +		device->con->write = sbi_dbcn_console_write;
> +	} else {
> +		if (IS_ENABLED(CONFIG_RISCV_SBI_V01))

"else if", no need for the extra block/indentation.

Regards,
Samuel

> +			device->con->write = sbi_0_1_console_write;
> +		else
> +			ret = -ENODEV;
> +	}
> +
> +	return ret;
>  }
>  EARLYCON_DECLARE(sbi, early_sbi_setup);
Re: [PATCH v4 3/5] tty/serial: Add RISC-V SBI debug console based earlycon
Posted by Anup Patel 2 years, 1 month ago 
On Wed, Nov 22, 2023 at 4:11 AM Samuel Holland
<samuel.holland@sifive.com> wrote:
>
> Hi Anup,
>
> On 2023-11-17 9:38 PM, Anup Patel wrote:
> > We extend the existing RISC-V SBI earlycon support to use the new
> > RISC-V SBI debug console extension.
> >
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> > ---
> >  drivers/tty/serial/Kconfig              |  2 +-
> >  drivers/tty/serial/earlycon-riscv-sbi.c | 24 ++++++++++++++++++++----
> >  2 files changed, 21 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> > index 732c893c8d16..1f2594b8ab9d 100644
> > --- a/drivers/tty/serial/Kconfig
> > +++ b/drivers/tty/serial/Kconfig
> > @@ -87,7 +87,7 @@ config SERIAL_EARLYCON_SEMIHOST
> >
> >  config SERIAL_EARLYCON_RISCV_SBI
> >       bool "Early console using RISC-V SBI"
> > -     depends on RISCV_SBI_V01
> > +     depends on RISCV_SBI
> >       select SERIAL_CORE
> >       select SERIAL_CORE_CONSOLE
> >       select SERIAL_EARLYCON
> > diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c
> > index 27afb0b74ea7..5351e1e31f45 100644
> > --- a/drivers/tty/serial/earlycon-riscv-sbi.c
> > +++ b/drivers/tty/serial/earlycon-riscv-sbi.c
> > @@ -15,17 +15,33 @@ static void sbi_putc(struct uart_port *port, unsigned char c)
> >       sbi_console_putchar(c);
> >  }
> >
> > -static void sbi_console_write(struct console *con,
> > -                           const char *s, unsigned n)
> > +static void sbi_0_1_console_write(struct console *con,
> > +                               const char *s, unsigned int n)
> >  {
> >       struct earlycon_device *dev = con->data;
> >       uart_console_write(&dev->port, s, n, sbi_putc);
> >  }
> >
> > +static void sbi_dbcn_console_write(struct console *con,
> > +                                const char *s, unsigned int n)
> > +{
> > +     sbi_debug_console_write(n, __pa(s));
>
> This only works for strings in the linear mapping or the kernel mapping (not
> vmalloc, which includes the stack). So I don't think we can use __pa() here.

In which case, we need extend sbi_debug_console_write() to
do the va-to-pa conversion for both earlycon-riscv-sbi.c and
hvc_riscv_sbi.c

>
> > +}
> > +
> >  static int __init early_sbi_setup(struct earlycon_device *device,
> >                                 const char *opt)
> >  {
> > -     device->con->write = sbi_console_write;
> > -     return 0;
> > +     int ret = 0;
> > +
> > +     if (sbi_debug_console_available) {
> > +             device->con->write = sbi_dbcn_console_write;
> > +     } else {
> > +             if (IS_ENABLED(CONFIG_RISCV_SBI_V01))
>
> "else if", no need for the extra block/indentation.

Okay, I will update.

>
> Regards,
> Samuel
>
> > +                     device->con->write = sbi_0_1_console_write;
> > +             else
> > +                     ret = -ENODEV;
> > +     }
> > +
> > +     return ret;
> >  }
> >  EARLYCON_DECLARE(sbi, early_sbi_setup);
>

Regards,
Anup

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