| Message ID | 20220302101925.210810-1-woodylin@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | serial: samsung: Add samsung_early_read to support early kgdboc | expand |
On 02/03/2022 11:19, Woody Lin wrote: > The 'kgdboc_earlycon_init' looks for boot console that has both .read > and .write callbacks. Adds 'samsung_early_read' to samsung_tty.c's early > console to support kgdboc. > > Signed-off-by: Woody Lin <woodylin@google.com> > --- > drivers/tty/serial/samsung_tty.c | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c > index d002a4e48ed9..eeb30d016ff1 100644 > --- a/drivers/tty/serial/samsung_tty.c > +++ b/drivers/tty/serial/samsung_tty.c > @@ -2949,6 +2949,7 @@ static void wr_reg_barrier(struct uart_port *port, u32 reg, u32 val) > > struct samsung_early_console_data { > u32 txfull_mask; > + u32 rxfifo_mask; > }; > > static void samsung_early_busyuart(struct uart_port *port) > @@ -2983,6 +2984,26 @@ static void samsung_early_write(struct console *con, const char *s, > uart_console_write(&dev->port, s, n, samsung_early_putc); > } > > +static int samsung_early_read(struct console *con, char *s, unsigned int n) > +{ > + struct earlycon_device *dev = con->data; > + struct samsung_early_console_data *data = dev->port.private_data; This can be const. Rest looks ok. Best regards, Krzysztof
On Wed, Mar 2, 2022 at 7:14 PM Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> wrote: > > On 02/03/2022 11:19, Woody Lin wrote: > > The 'kgdboc_earlycon_init' looks for boot console that has both .read > > and .write callbacks. Adds 'samsung_early_read' to samsung_tty.c's early > > console to support kgdboc. > > > > Signed-off-by: Woody Lin <woodylin@google.com> > > --- > > drivers/tty/serial/samsung_tty.c | 25 +++++++++++++++++++++++++ > > 1 file changed, 25 insertions(+) > > > > diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c > > index d002a4e48ed9..eeb30d016ff1 100644 > > --- a/drivers/tty/serial/samsung_tty.c > > +++ b/drivers/tty/serial/samsung_tty.c > > @@ -2949,6 +2949,7 @@ static void wr_reg_barrier(struct uart_port *port, u32 reg, u32 val) > > > > struct samsung_early_console_data { > > u32 txfull_mask; > > + u32 rxfifo_mask; > > }; > > > > static void samsung_early_busyuart(struct uart_port *port) > > @@ -2983,6 +2984,26 @@ static void samsung_early_write(struct console *con, const char *s, > > uart_console_write(&dev->port, s, n, samsung_early_putc); > > } > > > > +static int samsung_early_read(struct console *con, char *s, unsigned int n) > > +{ > > + struct earlycon_device *dev = con->data; > > + struct samsung_early_console_data *data = dev->port.private_data; > > This can be const. > > Rest looks ok. > Thanks, PATCH v2 is uploaded. Regards, Woody > > Best regards, > Krzysztof
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index d002a4e48ed9..eeb30d016ff1 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -2949,6 +2949,7 @@ static void wr_reg_barrier(struct uart_port *port, u32 reg, u32 val) struct samsung_early_console_data { u32 txfull_mask; + u32 rxfifo_mask; }; static void samsung_early_busyuart(struct uart_port *port) @@ -2983,6 +2984,26 @@ static void samsung_early_write(struct console *con, const char *s, uart_console_write(&dev->port, s, n, samsung_early_putc); } +static int samsung_early_read(struct console *con, char *s, unsigned int n) +{ + struct earlycon_device *dev = con->data; + struct samsung_early_console_data *data = dev->port.private_data; + int ch, ufstat, num_read = 0; + + while (num_read < n) { + ufstat = rd_regl(&dev->port, S3C2410_UFSTAT); + if (!(ufstat & data->rxfifo_mask)) + break; + ch = rd_reg(&dev->port, S3C2410_URXH); + if (ch == NO_POLL_CHAR) + break; + + s[num_read++] = ch; + } + + return num_read; +} + static int __init samsung_early_console_setup(struct earlycon_device *device, const char *opt) { @@ -2990,12 +3011,14 @@ static int __init samsung_early_console_setup(struct earlycon_device *device, return -ENODEV; device->con->write = samsung_early_write; + device->con->read = samsung_early_read; return 0; } /* S3C2410 */ static struct samsung_early_console_data s3c2410_early_console_data = { .txfull_mask = S3C2410_UFSTAT_TXFULL, + .rxfifo_mask = S3C2410_UFSTAT_RXFULL | S3C2410_UFSTAT_RXMASK, }; static int __init s3c2410_early_console_setup(struct earlycon_device *device, @@ -3011,6 +3034,7 @@ OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart", /* S3C2412, S3C2440, S3C64xx */ static struct samsung_early_console_data s3c2440_early_console_data = { .txfull_mask = S3C2440_UFSTAT_TXFULL, + .rxfifo_mask = S3C2440_UFSTAT_RXFULL | S3C2440_UFSTAT_RXMASK, }; static int __init s3c2440_early_console_setup(struct earlycon_device *device, @@ -3030,6 +3054,7 @@ OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart", /* S5PV210, Exynos */ static struct samsung_early_console_data s5pv210_early_console_data = { .txfull_mask = S5PV210_UFSTAT_TXFULL, + .rxfifo_mask = S5PV210_UFSTAT_RXFULL | S5PV210_UFSTAT_RXMASK, }; static int __init s5pv210_early_console_setup(struct earlycon_device *device,
The 'kgdboc_earlycon_init' looks for boot console that has both .read and .write callbacks. Adds 'samsung_early_read' to samsung_tty.c's early console to support kgdboc. Signed-off-by: Woody Lin <woodylin@google.com> --- drivers/tty/serial/samsung_tty.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)