| Message ID | 20210515084519.167343-1-shorne@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | serial/liteuart; Add support for earlycon | expand |
I pulled the trigger a bit early, the subject needs a bit better/consistent formatting. It should be: serial: liteuart: Add support for earlycon On Sat, May 15, 2021 at 05:45:18PM +0900, Stafford Horne wrote: > Most litex boards using RISC-V soft cores us the sbi earlycon, however > this is not available for non RISC-V litex SoC. This patch enables > earlycon for liteuart which is available on all Litex SoC's making > support for earycon debugging more widely available. > > Signed-off-by: Stafford Horne <shorne@gmail.com> > Cc: Florent Kermarrec <florent@enjoy-digital.fr> > Cc: Mateusz Holenko <mholenko@antmicro.com> > Cc: Joel Stanley <joel@jms.id.au> > Cc: Gabriel L. Somlo <gsomlo@gmail.com> > --- > .../admin-guide/kernel-parameters.txt | 5 +++ > drivers/tty/serial/Kconfig | 1 + > drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ > 3 files changed, 37 insertions(+) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 04545725f187..2d4a43af8de2 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -1084,6 +1084,11 @@ > the driver will use only 32-bit accessors to read/write > the device registers. > > + liteuart,<addr> > + Start an early console on a litex serial port at the > + specified address. The serial port must already be > + setup and configured. Options are not yet supported. > + > meson,<addr> > Start an early, polled-mode console on a meson serial > port at the specified address. The serial port must > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index 0c4cd4a348f4..9ceffe6ab6fd 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART > depends on OF || COMPILE_TEST > depends on LITEX > select SERIAL_CORE > + select SERIAL_EARLYCON > help > This driver is for the FPGA-based LiteUART serial controller from LiteX > SoC builder. > diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c > index 64842f3539e1..38c472487e68 100644 > --- a/drivers/tty/serial/liteuart.c > +++ b/drivers/tty/serial/liteuart.c > @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) > console_initcall(liteuart_console_init); > #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ > > +#ifdef CONFIG_SERIAL_EARLYCON > +static void early_liteuart_putc(struct uart_port *port, int c) > +{ > + while (litex_read8(port->membase + OFF_TXFULL)) > + cpu_relax(); > + > + litex_write8(port->membase + OFF_RXTX, c); > +} > + > +static void early_liteuart_write(struct console *console, const char *s, > + unsigned int count) > +{ > + struct earlycon_device *device = console->data; > + struct uart_port *port = &device->port; > + > + uart_console_write(port, s, count, early_liteuart_putc); > +} > + > +static int __init early_liteuart_setup(struct earlycon_device *device, > + const char *options) > +{ > + if (!device->port.membase) > + return -ENODEV; > + > + device->con->write = early_liteuart_write; > + return 0; > +} > + > +OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup); > +#endif /* CONFIG_SERIAL_EARLYCON */ > + > static int __init liteuart_init(void) > { > int res; > -- > 2.31.1 >
On 15. 05. 21, 10:45, Stafford Horne wrote: > Most litex boards using RISC-V soft cores us the sbi earlycon, however > this is not available for non RISC-V litex SoC. This patch enables > earlycon for liteuart which is available on all Litex SoC's making > support for earycon debugging more widely available. > > Signed-off-by: Stafford Horne <shorne@gmail.com> > Cc: Florent Kermarrec <florent@enjoy-digital.fr> > Cc: Mateusz Holenko <mholenko@antmicro.com> > Cc: Joel Stanley <joel@jms.id.au> > Cc: Gabriel L. Somlo <gsomlo@gmail.com> > --- > .../admin-guide/kernel-parameters.txt | 5 +++ > drivers/tty/serial/Kconfig | 1 + > drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ > 3 files changed, 37 insertions(+) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 04545725f187..2d4a43af8de2 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -1084,6 +1084,11 @@ > the driver will use only 32-bit accessors to read/write > the device registers. > > + liteuart,<addr> > + Start an early console on a litex serial port at the > + specified address. The serial port must already be > + setup and configured. Options are not yet supported. > + > meson,<addr> > Start an early, polled-mode console on a meson serial > port at the specified address. The serial port must > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index 0c4cd4a348f4..9ceffe6ab6fd 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART > depends on OF || COMPILE_TEST > depends on LITEX > select SERIAL_CORE > + select SERIAL_EARLYCON > help > This driver is for the FPGA-based LiteUART serial controller from LiteX > SoC builder. > diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c > index 64842f3539e1..38c472487e68 100644 > --- a/drivers/tty/serial/liteuart.c > +++ b/drivers/tty/serial/liteuart.c > @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) > console_initcall(liteuart_console_init); > #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ > > +#ifdef CONFIG_SERIAL_EARLYCON > +static void early_liteuart_putc(struct uart_port *port, int c) > +{ > + while (litex_read8(port->membase + OFF_TXFULL)) > + cpu_relax(); > + > + litex_write8(port->membase + OFF_RXTX, c); Hi, am I missing something or this doesn't differ to liteuart_putchar? > +} > + > +static void early_liteuart_write(struct console *console, const char *s, > + unsigned int count) > +{ > + struct earlycon_device *device = console->data; > + struct uart_port *port = &device->port; > + > + uart_console_write(port, s, count, early_liteuart_putc); > +} > + > +static int __init early_liteuart_setup(struct earlycon_device *device, > + const char *options) > +{ > + if (!device->port.membase) > + return -ENODEV; > + > + device->con->write = early_liteuart_write; > + return 0; > +} > + > +OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup); > +#endif /* CONFIG_SERIAL_EARLYCON */ > + > static int __init liteuart_init(void) > { > int res; > -- js suse labs
On Mon, May 17, 2021 at 10:16:43AM +0200, Jiri Slaby wrote: > On 15. 05. 21, 10:45, Stafford Horne wrote: > > Most litex boards using RISC-V soft cores us the sbi earlycon, however > > this is not available for non RISC-V litex SoC. This patch enables > > earlycon for liteuart which is available on all Litex SoC's making > > support for earycon debugging more widely available. > > > > Signed-off-by: Stafford Horne <shorne@gmail.com> > > Cc: Florent Kermarrec <florent@enjoy-digital.fr> > > Cc: Mateusz Holenko <mholenko@antmicro.com> > > Cc: Joel Stanley <joel@jms.id.au> > > Cc: Gabriel L. Somlo <gsomlo@gmail.com> > > --- > > .../admin-guide/kernel-parameters.txt | 5 +++ > > drivers/tty/serial/Kconfig | 1 + > > drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ > > 3 files changed, 37 insertions(+) > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > index 04545725f187..2d4a43af8de2 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -1084,6 +1084,11 @@ > > the driver will use only 32-bit accessors to read/write > > the device registers. > > + liteuart,<addr> > > + Start an early console on a litex serial port at the > > + specified address. The serial port must already be > > + setup and configured. Options are not yet supported. > > + > > meson,<addr> > > Start an early, polled-mode console on a meson serial > > port at the specified address. The serial port must > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > > index 0c4cd4a348f4..9ceffe6ab6fd 100644 > > --- a/drivers/tty/serial/Kconfig > > +++ b/drivers/tty/serial/Kconfig > > @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART > > depends on OF || COMPILE_TEST > > depends on LITEX > > select SERIAL_CORE > > + select SERIAL_EARLYCON > > help > > This driver is for the FPGA-based LiteUART serial controller from LiteX > > SoC builder. > > diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c > > index 64842f3539e1..38c472487e68 100644 > > --- a/drivers/tty/serial/liteuart.c > > +++ b/drivers/tty/serial/liteuart.c > > @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) > > console_initcall(liteuart_console_init); > > #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ > > +#ifdef CONFIG_SERIAL_EARLYCON > > +static void early_liteuart_putc(struct uart_port *port, int c) > > +{ > > + while (litex_read8(port->membase + OFF_TXFULL)) > > + cpu_relax(); > > + > > + litex_write8(port->membase + OFF_RXTX, c); > > Hi, > > am I missing something or this doesn't differ to liteuart_putchar? Hi, No you are right, I missed that thanks for catching it. I should be able to remove this function and use putchar below. -Stafford > > +} > > + > > +static void early_liteuart_write(struct console *console, const char *s, > > + unsigned int count) > > +{ > > + struct earlycon_device *device = console->data; > > + struct uart_port *port = &device->port; > > + > > + uart_console_write(port, s, count, early_liteuart_putc); > > +} > > + > > +static int __init early_liteuart_setup(struct earlycon_device *device, > > + const char *options) > > +{ > > + if (!device->port.membase) > > + return -ENODEV; > > + > > + device->con->write = early_liteuart_write; > > + return 0; > > +} > > + > > +OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup); > > +#endif /* CONFIG_SERIAL_EARLYCON */ > > + > > static int __init liteuart_init(void) > > { > > int res; > > > > > -- > js > suse labs
On 17. 05. 21, 10:23, Stafford Horne wrote: > On Mon, May 17, 2021 at 10:16:43AM +0200, Jiri Slaby wrote: >> On 15. 05. 21, 10:45, Stafford Horne wrote: >>> Most litex boards using RISC-V soft cores us the sbi earlycon, however >>> this is not available for non RISC-V litex SoC. This patch enables >>> earlycon for liteuart which is available on all Litex SoC's making >>> support for earycon debugging more widely available. >>> >>> Signed-off-by: Stafford Horne <shorne@gmail.com> >>> Cc: Florent Kermarrec <florent@enjoy-digital.fr> >>> Cc: Mateusz Holenko <mholenko@antmicro.com> >>> Cc: Joel Stanley <joel@jms.id.au> >>> Cc: Gabriel L. Somlo <gsomlo@gmail.com> >>> --- >>> .../admin-guide/kernel-parameters.txt | 5 +++ >>> drivers/tty/serial/Kconfig | 1 + >>> drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ >>> 3 files changed, 37 insertions(+) >>> >>> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >>> index 04545725f187..2d4a43af8de2 100644 >>> --- a/Documentation/admin-guide/kernel-parameters.txt >>> +++ b/Documentation/admin-guide/kernel-parameters.txt >>> @@ -1084,6 +1084,11 @@ >>> the driver will use only 32-bit accessors to read/write >>> the device registers. >>> + liteuart,<addr> >>> + Start an early console on a litex serial port at the >>> + specified address. The serial port must already be >>> + setup and configured. Options are not yet supported. >>> + >>> meson,<addr> >>> Start an early, polled-mode console on a meson serial >>> port at the specified address. The serial port must >>> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig >>> index 0c4cd4a348f4..9ceffe6ab6fd 100644 >>> --- a/drivers/tty/serial/Kconfig >>> +++ b/drivers/tty/serial/Kconfig >>> @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART >>> depends on OF || COMPILE_TEST >>> depends on LITEX >>> select SERIAL_CORE >>> + select SERIAL_EARLYCON >>> help >>> This driver is for the FPGA-based LiteUART serial controller from LiteX >>> SoC builder. >>> diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c >>> index 64842f3539e1..38c472487e68 100644 >>> --- a/drivers/tty/serial/liteuart.c >>> +++ b/drivers/tty/serial/liteuart.c >>> @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) >>> console_initcall(liteuart_console_init); >>> #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ >>> +#ifdef CONFIG_SERIAL_EARLYCON >>> +static void early_liteuart_putc(struct uart_port *port, int c) >>> +{ >>> + while (litex_read8(port->membase + OFF_TXFULL)) >>> + cpu_relax(); >>> + >>> + litex_write8(port->membase + OFF_RXTX, c); >> >> Hi, >> >> am I missing something or this doesn't differ to liteuart_putchar? > > Hi, No you are right, I missed that thanks for catching it. > > I should be able to remove this function and use putchar below. OK. I've just noticed you add an ifdef CONFIG_SERIAL_EARLYCON here, but you select SERIAL_EARLYCON in Kconfig above. So the ifdef is sort of pointless? (Or you shouldn't select SERIAL_EARLYCON.) thanks, -- js suse labs
On Mon, May 17, 2021 at 10:25:46AM +0200, Jiri Slaby wrote: > On 17. 05. 21, 10:23, Stafford Horne wrote: > > On Mon, May 17, 2021 at 10:16:43AM +0200, Jiri Slaby wrote: > > > On 15. 05. 21, 10:45, Stafford Horne wrote: > > > > Most litex boards using RISC-V soft cores us the sbi earlycon, however > > > > this is not available for non RISC-V litex SoC. This patch enables > > > > earlycon for liteuart which is available on all Litex SoC's making > > > > support for earycon debugging more widely available. > > > > > > > > Signed-off-by: Stafford Horne <shorne@gmail.com> > > > > Cc: Florent Kermarrec <florent@enjoy-digital.fr> > > > > Cc: Mateusz Holenko <mholenko@antmicro.com> > > > > Cc: Joel Stanley <joel@jms.id.au> > > > > Cc: Gabriel L. Somlo <gsomlo@gmail.com> > > > > --- > > > > .../admin-guide/kernel-parameters.txt | 5 +++ > > > > drivers/tty/serial/Kconfig | 1 + > > > > drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ > > > > 3 files changed, 37 insertions(+) > > > > > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > > > index 04545725f187..2d4a43af8de2 100644 > > > > --- a/Documentation/admin-guide/kernel-parameters.txt > > > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > > > @@ -1084,6 +1084,11 @@ > > > > the driver will use only 32-bit accessors to read/write > > > > the device registers. > > > > + liteuart,<addr> > > > > + Start an early console on a litex serial port at the > > > > + specified address. The serial port must already be > > > > + setup and configured. Options are not yet supported. > > > > + > > > > meson,<addr> > > > > Start an early, polled-mode console on a meson serial > > > > port at the specified address. The serial port must > > > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > > > > index 0c4cd4a348f4..9ceffe6ab6fd 100644 > > > > --- a/drivers/tty/serial/Kconfig > > > > +++ b/drivers/tty/serial/Kconfig > > > > @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART > > > > depends on OF || COMPILE_TEST > > > > depends on LITEX > > > > select SERIAL_CORE > > > > + select SERIAL_EARLYCON > > > > help > > > > This driver is for the FPGA-based LiteUART serial controller from LiteX > > > > SoC builder. > > > > diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c > > > > index 64842f3539e1..38c472487e68 100644 > > > > --- a/drivers/tty/serial/liteuart.c > > > > +++ b/drivers/tty/serial/liteuart.c > > > > @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) > > > > console_initcall(liteuart_console_init); > > > > #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ > > > > +#ifdef CONFIG_SERIAL_EARLYCON > > > > +static void early_liteuart_putc(struct uart_port *port, int c) > > > > +{ > > > > + while (litex_read8(port->membase + OFF_TXFULL)) > > > > + cpu_relax(); > > > > + > > > > + litex_write8(port->membase + OFF_RXTX, c); > > > > > > Hi, > > > > > > am I missing something or this doesn't differ to liteuart_putchar? > > > > Hi, No you are right, I missed that thanks for catching it. > > > > I should be able to remove this function and use putchar below. > > OK. > > I've just noticed you add an ifdef CONFIG_SERIAL_EARLYCON here, but you > select SERIAL_EARLYCON in Kconfig above. So the ifdef is sort of pointless? > (Or you shouldn't select SERIAL_EARLYCON.) Ah yes, this I thought might have been wrong when I wrote it. I think my problem here is I was just copying how some other patches implemented earlycon. omap-serial - has ifdefs, doesn't select SERIAL_EARLYCON - looks ok sifive - has ifdefs + select SERIAL_EARLYCON - maybe needs cleanup too -Stafford
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 04545725f187..2d4a43af8de2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1084,6 +1084,11 @@ the driver will use only 32-bit accessors to read/write the device registers. + liteuart,<addr> + Start an early console on a litex serial port at the + specified address. The serial port must already be + setup and configured. Options are not yet supported. + meson,<addr> Start an early, polled-mode console on a meson serial port at the specified address. The serial port must diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 0c4cd4a348f4..9ceffe6ab6fd 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1531,6 +1531,7 @@ config SERIAL_LITEUART depends on OF || COMPILE_TEST depends on LITEX select SERIAL_CORE + select SERIAL_EARLYCON help This driver is for the FPGA-based LiteUART serial controller from LiteX SoC builder. diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c index 64842f3539e1..38c472487e68 100644 --- a/drivers/tty/serial/liteuart.c +++ b/drivers/tty/serial/liteuart.c @@ -372,6 +372,37 @@ static int __init liteuart_console_init(void) console_initcall(liteuart_console_init); #endif /* CONFIG_SERIAL_LITEUART_CONSOLE */ +#ifdef CONFIG_SERIAL_EARLYCON +static void early_liteuart_putc(struct uart_port *port, int c) +{ + while (litex_read8(port->membase + OFF_TXFULL)) + cpu_relax(); + + litex_write8(port->membase + OFF_RXTX, c); +} + +static void early_liteuart_write(struct console *console, const char *s, + unsigned int count) +{ + struct earlycon_device *device = console->data; + struct uart_port *port = &device->port; + + uart_console_write(port, s, count, early_liteuart_putc); +} + +static int __init early_liteuart_setup(struct earlycon_device *device, + const char *options) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = early_liteuart_write; + return 0; +} + +OF_EARLYCON_DECLARE(liteuart, "litex,liteuart", early_liteuart_setup); +#endif /* CONFIG_SERIAL_EARLYCON */ + static int __init liteuart_init(void) { int res;
Most litex boards using RISC-V soft cores us the sbi earlycon, however this is not available for non RISC-V litex SoC. This patch enables earlycon for liteuart which is available on all Litex SoC's making support for earycon debugging more widely available. Signed-off-by: Stafford Horne <shorne@gmail.com> Cc: Florent Kermarrec <florent@enjoy-digital.fr> Cc: Mateusz Holenko <mholenko@antmicro.com> Cc: Joel Stanley <joel@jms.id.au> Cc: Gabriel L. Somlo <gsomlo@gmail.com> --- .../admin-guide/kernel-parameters.txt | 5 +++ drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/liteuart.c | 31 +++++++++++++++++++ 3 files changed, 37 insertions(+)