Add support for DT based early console on platforms with the msm
serial hardware.
Cc: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
---
I've tested this on top of Rob's arm-fixmap[1] branch and a cherry-pick
of commit 68252424a7c7 (tty: serial: msm: Support big-endian CPUs, 2014-06-30)
and the merge of commit 45e0f0f56843 (tty/serial: pl011: add DT based earlycon
support, 2014-03-27)
[1] git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git arm-fixmap
drivers/tty/serial/Kconfig | 1 +
drivers/tty/serial/msm_serial.c | 72 ++++++++++++++++++++++++++++++++++-------
2 files changed, 61 insertions(+), 12 deletions(-)
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 26cec64dadd7..903a3277fa60 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1051,6 +1051,7 @@ config SERIAL_MSM_CONSOLE
bool "MSM serial console support"
depends on SERIAL_MSM=y
select SERIAL_CORE_CONSOLE
+ select SERIAL_EARLYCON
config SERIAL_MSM_HS
tristate "MSM UART High Speed: Serial Driver"
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index c549110509bb..d68faa2e7a6c 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -856,22 +856,15 @@ static inline struct uart_port *get_port_from_line(unsigned int line)
}
#ifdef CONFIG_SERIAL_MSM_CONSOLE
-static void msm_console_write(struct console *co, const char *s,
- unsigned int count)
+static void __msm_console_write(struct uart_port *port, const char *s,
+ unsigned int count, bool is_uartdm)
{
int i;
- struct uart_port *port;
- struct msm_port *msm_port;
int num_newlines = 0;
bool replaced = false;
void __iomem *tf;
- BUG_ON(co->index < 0 || co->index >= UART_NR);
-
- port = get_port_from_line(co->index);
- msm_port = UART_TO_MSM(port);
-
- if (msm_port->is_uartdm)
+ if (is_uartdm)
tf = port->membase + UARTDM_TF;
else
tf = port->membase + UART_TF;
@@ -883,7 +876,7 @@ static void msm_console_write(struct console *co, const char *s,
count += num_newlines;
spin_lock(&port->lock);
- if (msm_port->is_uartdm)
+ if (is_uartdm)
reset_dm_count(port, count);
i = 0;
@@ -892,7 +885,7 @@ static void msm_console_write(struct console *co, const char *s,
unsigned int num_chars;
char buf[4] = { 0 };
- if (msm_port->is_uartdm)
+ if (is_uartdm)
num_chars = min(count - i, (unsigned int)sizeof(buf));
else
num_chars = 1;
@@ -921,6 +914,20 @@ static void msm_console_write(struct console *co, const char *s,
spin_unlock(&port->lock);
}
+static void msm_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct uart_port *port;
+ struct msm_port *msm_port;
+
+ BUG_ON(co->index < 0 || co->index >= UART_NR);
+
+ port = get_port_from_line(co->index);
+ msm_port = UART_TO_MSM(port);
+
+ __msm_console_write(port, s, count, msm_port->is_uartdm);
+}
+
static int __init msm_console_setup(struct console *co, char *options)
{
struct uart_port *port;
@@ -963,6 +970,47 @@ static int __init msm_console_setup(struct console *co, char *options)
return uart_set_options(port, co, baud, parity, bits, flow);
}
+static void
+msm_serial_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ __msm_console_write(&dev->port, s, n, false);
+}
+
+static int __init
+msm_serial_early_console_setup(struct earlycon_device *device, const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = msm_serial_early_write;
+ return 0;
+}
+OF_EARLYCON_DECLARE(msm_serial, "qcom,msm-uart",
+ msm_serial_early_console_setup);
+
+static void
+msm_serial_early_write_dm(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ __msm_console_write(&dev->port, s, n, true);
+}
+
+static int __init
+msm_serial_early_console_setup_dm(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = msm_serial_early_write_dm;
+ return 0;
+}
+OF_EARLYCON_DECLARE(msm_serial_dm, "qcom,msm-uartdm",
+ msm_serial_early_console_setup_dm);
+
static struct uart_driver msm_uart_driver;
static struct console msm_console = {
--
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