Use CONFIG_CONSOLE_MUX for netconsole. When netconsole is running,
stdin/stdout/stder must be set to some primary console, in addtion to nc.
For example, stdin=serial,nc. Some recent Linux kernels will not boot with
only nc on the stdout list, ie. stdout=nc. When netconsole exits, remove
nc from the list of devices in stdin/stdout/stderr.
Signed-off-by: Tony Dinh <mibo...@gmail.com>
---
Changes in v2:
- Select CONFIG_CONSOLE_MUX if CONFIG_NETCONSOLE is enabled
- Add new functions in netconsole driver to support CONSOLE_MUX
- Add new function to encapsulate the process of stopping netconsole
from bootm
- Remove unecessary net_timeout initial value = 1
boot/bootm.c | 13 ++++++---
drivers/net/Kconfig | 10 +++++++
drivers/net/netconsole.c | 60 ++++++++++++++++++++++++++++++++++++++++
include/stdio_dev.h | 1 +
4 files changed, 80 insertions(+), 4 deletions(-)
diff --git a/boot/bootm.c b/boot/bootm.c
index 2eec60ec7b..11203c01ec 100644
--- a/boot/bootm.c
+++ b/boot/bootm.c
@@ -472,11 +472,16 @@ ulong bootm_disable_interrupts(void)
* recover from any failures any more...
*/
iflag = disable_interrupts();
-#ifdef CONFIG_NETCONSOLE
- /* Stop the ethernet stack if NetConsole could have left it up */
- eth_halt();
-#endif
+ if (IS_ENABLED(CONFIG_NETCONSOLE)) {
+ /*
+ * Make sure that the starting kernel message printed out,
+ * stop netconsole and the ethernet stack
+ */
+ printf("\n\nStarting kernel ...\n\n");
+ drv_nc_stop();
+ eth_halt();
+ }
#if defined(CONFIG_CMD_USB)
/*
* turn off USB to prevent the host controller from writing to the
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index ceadee98a1..0661059dfa 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -945,4 +945,14 @@ config MDIO_MUX_MESON_G12A
This driver is used for the MDIO mux found on the Amlogic G12A &
compatible
SoCs.
+config NETCONSOLE
+ bool "Enable netconsole"
+ select CONSOLE_MUX
+ help
+ NetConsole requires CONSOLE_MUX, i.e. at least one default console
such
+ must be specified in addition to nc console. For example, for boards
that
+ the main console is serial, set each of the envs stdin/stdout/stderr
to serial,nc.
+ See CONFIG_CONSOLE_MUX and CONFIG_SYS_CONSOLE_IS_IN_ENV help for
detailed
+ description of usage.
+
endif # NETDEVICES
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 151bc55e07..bb92d2e130 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -7,6 +7,7 @@
#include <common.h>
#include <command.h>
#include <env.h>
+#include <iomux.h>
#include <log.h>
#include <stdio_dev.h>
#include <net.h>
@@ -33,6 +34,12 @@ static int output_packet_len;
*/
enum proto_t net_loop_last_protocol = BOOTP;
+/*
+ * Net console helpers
+ */
+static void usage(void);
+static void remove_nc_from(const int console);
+
static void nc_wait_arp_handler(uchar *pkt, unsigned dest,
struct in_addr sip, unsigned src,
unsigned len)
@@ -111,6 +118,21 @@ static int refresh_settings_from_env(void)
return 0;
}
+static void remove_nc_from(const int console)
+{
+ int ret;
+
+ ret = iomux_replace_device(console, "nc", "nulldev");
+ if (ret) {
+ printf("\n*** Warning: Cannot remove nc from %s Error=%d\n",
+ stdio_names[console], ret);
+ printf("%s=", stdio_names[console]);
+ iomux_printdevs(console);
+ usage();
+ flush();
+ }
+}
+
/**
* Called from net_loop in net/net.c before each packet
*/
@@ -241,6 +263,29 @@ static int nc_stdio_start(struct stdio_dev *dev)
return 0;
}
+void nc_stdio_stop(void)
+{
+ if (IS_ENABLED(CONFIG_CONSOLE_MUX)) {
+ int ret;
+ struct stdio_dev *sdev;
+
+ /* Remove nc from each stdio file */
+ remove_nc_from(stdin);
+ remove_nc_from(stderr);
+ remove_nc_from(stdout);
+
+ /* Deregister nc device */
+ sdev = stdio_get_by_name("nc");
+ ret = stdio_deregister_dev(sdev, true);
+ if (ret)
+ printf("\nWarning: Cannot deregister nc console
Error=%d\n", ret);
+ } else {
+ printf("\n*** Warning: CONFIG_CONSOLE_MUX must be enabled for
netconsole\n"
+ "to work properly. The nc console will be removed
when\n"
+ "netconsole driver stops\n");
+ }
+}
+
static void nc_stdio_putc(struct stdio_dev *dev, char c)
{
if (output_recursion)
@@ -316,6 +361,16 @@ static int nc_stdio_tstc(struct stdio_dev *dev)
return input_size != 0;
}
+static void usage(void)
+{
+ printf("USAGE:\n"
+ "NetConsole requires CONFIG_CONSOLE_MUX. At least one default
console\n"
+ "must be specified in addition to nc console. For example, for
boards\n"
+ "that the main console is serial, set the each of envs
stdin/stdout/stderr\n"
+ "to serial,nc. Some kernel might fail to boot when nc is the
only device in\n"
+ "stdout list\n");
+}
+
int drv_nc_init(void)
{
struct stdio_dev dev;
@@ -335,3 +390,8 @@ int drv_nc_init(void)
return (rc == 0) ? 1 : rc;
}
+
+void drv_nc_stop(void)
+{
+ nc_stdio_stop();
+}
diff --git a/include/stdio_dev.h b/include/stdio_dev.h
index 3105928970..9d2375a67e 100644
--- a/include/stdio_dev.h
+++ b/include/stdio_dev.h
@@ -112,6 +112,7 @@ int drv_keyboard_init(void);
int drv_usbtty_init(void);
int drv_usbacm_init(void);
int drv_nc_init(void);
+void drv_nc_stop(void);
int drv_jtag_console_init(void);
int cbmemc_init(void);
--
2.30.2
