diff mbox series

[2/3] net: lwip: add sntp command

Message ID 20250521151516.16729-3-jerome.forissier@linaro.org
State New
Headers show
Series sntp for NET_LWIP | expand

Commit Message

Jerome Forissier May 21, 2025, 3:14 p.m. UTC 
Implement the sntp command when NET_LWIP=y.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
---

 cmd/Kconfig                |  13 ++--
 cmd/net-lwip.c             |   5 ++
 include/net-common.h       |  11 ++++
 lib/lwip/Makefile          |   1 +
 lib/lwip/u-boot/arch/cc.h  |   4 ++
 lib/lwip/u-boot/lwipopts.h |   4 ++
 net/lwip/Makefile          |   1 +
 net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
 8 files changed, 161 insertions(+), 6 deletions(-)
 create mode 100644 net/lwip/sntp.c

Comments

Heinrich Schuchardt June 2, 2025, 9:23 p.m. UTC | #1 
Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
>Implement the sntp command when NET_LWIP=y.
>
>Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
>---
>
> cmd/Kconfig                |  13 ++--
> cmd/net-lwip.c             |   5 ++
> include/net-common.h       |  11 ++++
> lib/lwip/Makefile          |   1 +
> lib/lwip/u-boot/arch/cc.h  |   4 ++
> lib/lwip/u-boot/lwipopts.h |   4 ++
> net/lwip/Makefile          |   1 +
> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
> 8 files changed, 161 insertions(+), 6 deletions(-)
> create mode 100644 net/lwip/sntp.c
>
>diff --git a/cmd/Kconfig b/cmd/Kconfig
>index f21d27cb27f..58f629e1c34 100644
>--- a/cmd/Kconfig
>+++ b/cmd/Kconfig
>@@ -2061,12 +2061,6 @@ config CMD_CDP
> 	  and to retrieve configuration data including the VLAN id using the
> 	  proprietary Cisco Discovery Protocol (CDP).
> 
>-config CMD_SNTP
>-	bool "sntp"
>-	select PROT_UDP
>-	help
>-	  Synchronize RTC via network
>-
> config CMD_LINK_LOCAL
> 	bool "linklocal"
> 	depends on (LIB_RAND || LIB_HW_RAND)
>@@ -2144,6 +2138,13 @@ config CMD_PING
> 	help
> 	  Send ICMP ECHO_REQUEST to network host
> 
>+config CMD_SNTP

The command should depend on RTC support.

>+	bool "sntp"
>+	select PROT_UDP if NET
>+	select PROT_UDP_LWIP if NET_LWIP
>+	help
>+	  Synchronize RTC via network
>+
> config CMD_TFTPBOOT
> 	bool "tftp"
> 	select PROT_UDP_LWIP if NET_LWIP
>diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
>index cecf8d02555..2ffee64f97e 100644
>--- a/cmd/net-lwip.c
>+++ b/cmd/net-lwip.c

Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.

>@@ -21,6 +21,11 @@ U_BOOT_CMD(tftpboot, 3, 0, do_tftpb,
> 	   "[loadAddress] [[hostIPaddr:]bootfilename]");
> #endif
> 
>+#if defined(CONFIG_CMD_SNTP)
>+U_BOOT_CMD(sntp, 2, 1, do_sntp, "synchronize RTC via network",
>+	   "[NTP server IP]");
>+#endif

Why wouldn't we support server names ( e.g.  0.de.pool.ntp.org) here if we have DNS enabled?

Please, add the missing documentation change for the commands.

Best regards

Heinrich


>+
> #if defined(CONFIG_CMD_DNS)
> U_BOOT_CMD(dns, 3, 1, do_dns, "lookup the IP of a hostname",
> 	   "hostname [envvar]");
>diff --git a/include/net-common.h b/include/net-common.h
>index a021bf503ff..b06cafb497e 100644
>--- a/include/net-common.h
>+++ b/include/net-common.h
>@@ -505,6 +505,17 @@ int dhcp_run(ulong addr, const char *fname, bool autoload);
>  */
> int do_ping(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
> 
>+/**
>+ * do_sntp - Run the sntp command
>+ *
>+ * @cmdtp: Unused
>+ * @flag: Command flags (CMD_FLAG_...)
>+ * @argc: Number of arguments
>+ * @argv: List of arguments
>+ * Return: result (see enum command_ret_t)
>+ */
>+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
>+
> /**
>  * do_tftpb - Run the tftpboot command
>  *
>diff --git a/lib/lwip/Makefile b/lib/lwip/Makefile
>index e9e8caee93a..c3f0e916f66 100644
>--- a/lib/lwip/Makefile
>+++ b/lib/lwip/Makefile
>@@ -13,6 +13,7 @@ obj-y += \
> 	lwip/src/api/sockets.o \
> 	lwip/src/api/tcpip.o \
> 	lwip/src/apps/http/http_client.o \
>+	lwip/src/apps/sntp/sntp.o \
> 	lwip/src/apps/tftp/tftp.o \
> 	lwip/src/core/altcp_alloc.o \
> 	lwip/src/core/altcp.o \
>diff --git a/lib/lwip/u-boot/arch/cc.h b/lib/lwip/u-boot/arch/cc.h
>index 6104c296f6f..f91127ac565 100644
>--- a/lib/lwip/u-boot/arch/cc.h
>+++ b/lib/lwip/u-boot/arch/cc.h
>@@ -43,4 +43,8 @@
> #define BYTE_ORDER BIG_ENDIAN
> #endif
> 
>+#define SNTP_STARTUP_DELAY 0
>+void sntp_set_system_time(uint32_t sec);
>+#define SNTP_SET_SYSTEM_TIME(sec) sntp_set_system_time(sec)
>+
> #endif /* LWIP_ARCH_CC_H */
>diff --git a/lib/lwip/u-boot/lwipopts.h b/lib/lwip/u-boot/lwipopts.h
>index edac74ff7a2..14ba7bd7ae2 100644
>--- a/lib/lwip/u-boot/lwipopts.h
>+++ b/lib/lwip/u-boot/lwipopts.h
>@@ -162,4 +162,8 @@
> #define LWIP_ALTCP_TLS_MBEDTLS          1
> #endif
> 
>+#if defined(CONFIG_CMD_SNTP)
>+#define LWIP_DHCP_GET_NTP_SRV 1
>+#endif
>+
> #endif /* LWIP_UBOOT_LWIPOPTS_H */
>diff --git a/net/lwip/Makefile b/net/lwip/Makefile
>index 5df222589b8..5bb98dc4d98 100644
>--- a/net/lwip/Makefile
>+++ b/net/lwip/Makefile
>@@ -4,6 +4,7 @@ obj-$(CONFIG_$(PHASE_)DM_ETH) += net-lwip.o
> obj-$(CONFIG_CMD_DHCP) += dhcp.o
> obj-$(CONFIG_CMD_DNS) += dns.o
> obj-$(CONFIG_CMD_PING) += ping.o
>+obj-$(CONFIG_CMD_SNTP) += sntp.o
> obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
> obj-$(CONFIG_WGET) += wget.o
> 
>diff --git a/net/lwip/sntp.c b/net/lwip/sntp.c
>new file mode 100644
>index 00000000000..3b2bc3c679d
>--- /dev/null
>+++ b/net/lwip/sntp.c
>@@ -0,0 +1,128 @@
>+// SPDX-License-Identifier: GPL-2.0+
>+/* Copyright (C) 2025 Linaro Ltd. */
>+
>+#include <command.h>
>+#include <console.h>
>+#include <dm/device.h>
>+#include <lwip/apps/sntp.h>
>+#include <lwip/timeouts.h>
>+#include <net.h>
>+
>+#define SNTP_TIMEOUT 10000
>+
>+static enum done_state {
>+	NOT_DONE = 0,
>+	SUCCESS,
>+	ABORTED,
>+	TIMED_OUT
>+} sntp_state;
>+
>+static void no_response(void *arg)
>+{
>+	sntp_state = TIMED_OUT;
>+}
>+
>+/* Called by lwIP via the SNTP_SET_SYSTEM_TIME() macro */
>+void sntp_set_system_time(uint32_t seconds)
>+{
>+	char *toff;
>+	int net_ntp_time_offset = 0;
>+
>+	toff = env_get("timeoffset");
>+	if (toff)
>+		net_ntp_time_offset = simple_strtol(toff, NULL, 10);
>+
>+	net_sntp_set_rtc(seconds + net_ntp_time_offset);
>+	sntp_state = SUCCESS;
>+}
>+
>+static bool ntp_server_known(void)
>+{
>+	int i;
>+
>+	for (i = 0; i < SNTP_MAX_SERVERS; i++) {
>+		const ip_addr_t *ip = sntp_getserver(i);
>+
>+		if (ip && ip->addr)
>+			return true;
>+	}
>+
>+	return false;
>+}
>+
>+static int sntp_loop(struct udevice *udev, ip_addr_t *srvip)
>+{
>+	struct netif *netif;
>+
>+	netif = net_lwip_new_netif(udev);
>+	if (!netif)
>+		return -1;
>+
>+	sntp_state = NOT_DONE;
>+
>+	sntp_setoperatingmode(SNTP_OPMODE_POLL);
>+	sntp_servermode_dhcp(CONFIG_IS_ENABLED(CMD_DHCP));
>+	if (srvip) {
>+		sntp_setserver(0, srvip);
>+	} else {
>+		if (!ntp_server_known()) {
>+			log_err("error: ntpserverip not set\n");
>+			return -1;
>+		}
>+	}
>+	sntp_init();
>+
>+	sys_timeout(SNTP_TIMEOUT, no_response, NULL);
>+	while (sntp_state == NOT_DONE) {
>+		net_lwip_rx(udev, netif);
>+		sys_check_timeouts();
>+		if (ctrlc()) {
>+			printf("\nAbort\n");
>+			sntp_state = ABORTED;
>+			break;
>+		}
>+	}
>+	sys_untimeout(no_response, NULL);
>+
>+	sntp_stop();
>+	net_lwip_remove_netif(netif);
>+
>+	if (sntp_state == SUCCESS)
>+		return 0;
>+
>+	return -1;
>+}
>+
>+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
>+{
>+	ip_addr_t *srvip = NULL;
>+	char *server_ip = NULL;
>+	ip_addr_t ipaddr;
>+
>+	switch (argc) {
>+	case 1:
>+		server_ip = env_get("ntpserverip");
>+		break;
>+	case 2:
>+		server_ip = argv[1];
>+		break;
>+	default:
>+		return CMD_RET_USAGE;
>+	}
>+
>+	if (server_ip) {
>+		if (!ipaddr_aton(server_ip, &ipaddr)) {
>+			log_err("error: ipaddr_aton\n");
>+			return CMD_RET_FAILURE;
>+		}
>+		srvip = &ipaddr;
>+	}
>+
>+	if (net_lwip_eth_start() < 0)
>+		return CMD_RET_FAILURE;
>+
>+	if (sntp_loop(eth_get_dev(), srvip) < 0)
>+		return CMD_RET_FAILURE;
>+
>+	return CMD_RET_SUCCESS;
>+}
Heinrich Schuchardt June 3, 2025, 5:51 a.m. UTC | #2 
Am 2. Juni 2025 23:23:08 MESZ schrieb Heinrich Schuchardt <xypron.glpk@gmx.de>:
>Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
>>Implement the sntp command when NET_LWIP=y.

https://datatracker.ietf.org/doc/rfc5905/ describes that on Feb 7th, 2036 the 32 bit seconds field wraps around and era 1 starts.

Does our code consider this?

Best regards 

Heinrich



>>
>>Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
>>---
>>
>> cmd/Kconfig                |  13 ++--
>> cmd/net-lwip.c             |   5 ++
>> include/net-common.h       |  11 ++++
>> lib/lwip/Makefile          |   1 +
>> lib/lwip/u-boot/arch/cc.h  |   4 ++
>> lib/lwip/u-boot/lwipopts.h |   4 ++
>> net/lwip/Makefile          |   1 +
>> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
>> 8 files changed, 161 insertions(+), 6 deletions(-)
>> create mode 100644 net/lwip/sntp.c
>>
>>diff --git a/cmd/Kconfig b/cmd/Kconfig
>>index f21d27cb27f..58f629e1c34 100644
>>--- a/cmd/Kconfig
>>+++ b/cmd/Kconfig
>>@@ -2061,12 +2061,6 @@ config CMD_CDP
>> 	  and to retrieve configuration data including the VLAN id using the
>> 	  proprietary Cisco Discovery Protocol (CDP).
>> 
>>-config CMD_SNTP
>>-	bool "sntp"
>>-	select PROT_UDP
>>-	help
>>-	  Synchronize RTC via network
>>-
>> config CMD_LINK_LOCAL
>> 	bool "linklocal"
>> 	depends on (LIB_RAND || LIB_HW_RAND)
>>@@ -2144,6 +2138,13 @@ config CMD_PING
>> 	help
>> 	  Send ICMP ECHO_REQUEST to network host
>> 
>>+config CMD_SNTP
>
>The command should depend on RTC support.
>
>>+	bool "sntp"
>>+	select PROT_UDP if NET
>>+	select PROT_UDP_LWIP if NET_LWIP
>>+	help
>>+	  Synchronize RTC via network
>>+
>> config CMD_TFTPBOOT
>> 	bool "tftp"
>> 	select PROT_UDP_LWIP if NET_LWIP
>>diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
>>index cecf8d02555..2ffee64f97e 100644
>>--- a/cmd/net-lwip.c
>>+++ b/cmd/net-lwip.c
>
>Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.
>
>>@@ -21,6 +21,11 @@ U_BOOT_CMD(tftpboot, 3, 0, do_tftpb,
>> 	   "[loadAddress] [[hostIPaddr:]bootfilename]");
>> #endif
>> 
>>+#if defined(CONFIG_CMD_SNTP)
>>+U_BOOT_CMD(sntp, 2, 1, do_sntp, "synchronize RTC via network",
>>+	   "[NTP server IP]");
>>+#endif
>
>Why wouldn't we support server names ( e.g.  0.de.pool.ntp.org) here if we have DNS enabled?
>
>Please, add the missing documentation change for the commands.
>
>Best regards
>
>Heinrich
>
>
>>+
>> #if defined(CONFIG_CMD_DNS)
>> U_BOOT_CMD(dns, 3, 1, do_dns, "lookup the IP of a hostname",
>> 	   "hostname [envvar]");
>>diff --git a/include/net-common.h b/include/net-common.h
>>index a021bf503ff..b06cafb497e 100644
>>--- a/include/net-common.h
>>+++ b/include/net-common.h
>>@@ -505,6 +505,17 @@ int dhcp_run(ulong addr, const char *fname, bool autoload);
>>  */
>> int do_ping(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
>> 
>>+/**
>>+ * do_sntp - Run the sntp command
>>+ *
>>+ * @cmdtp: Unused
>>+ * @flag: Command flags (CMD_FLAG_...)
>>+ * @argc: Number of arguments
>>+ * @argv: List of arguments
>>+ * Return: result (see enum command_ret_t)
>>+ */
>>+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
>>+
>> /**
>>  * do_tftpb - Run the tftpboot command
>>  *
>>diff --git a/lib/lwip/Makefile b/lib/lwip/Makefile
>>index e9e8caee93a..c3f0e916f66 100644
>>--- a/lib/lwip/Makefile
>>+++ b/lib/lwip/Makefile
>>@@ -13,6 +13,7 @@ obj-y += \
>> 	lwip/src/api/sockets.o \
>> 	lwip/src/api/tcpip.o \
>> 	lwip/src/apps/http/http_client.o \
>>+	lwip/src/apps/sntp/sntp.o \
>> 	lwip/src/apps/tftp/tftp.o \
>> 	lwip/src/core/altcp_alloc.o \
>> 	lwip/src/core/altcp.o \
>>diff --git a/lib/lwip/u-boot/arch/cc.h b/lib/lwip/u-boot/arch/cc.h
>>index 6104c296f6f..f91127ac565 100644
>>--- a/lib/lwip/u-boot/arch/cc.h
>>+++ b/lib/lwip/u-boot/arch/cc.h
>>@@ -43,4 +43,8 @@
>> #define BYTE_ORDER BIG_ENDIAN
>> #endif
>> 
>>+#define SNTP_STARTUP_DELAY 0
>>+void sntp_set_system_time(uint32_t sec);
>>+#define SNTP_SET_SYSTEM_TIME(sec) sntp_set_system_time(sec)
>>+
>> #endif /* LWIP_ARCH_CC_H */
>>diff --git a/lib/lwip/u-boot/lwipopts.h b/lib/lwip/u-boot/lwipopts.h
>>index edac74ff7a2..14ba7bd7ae2 100644
>>--- a/lib/lwip/u-boot/lwipopts.h
>>+++ b/lib/lwip/u-boot/lwipopts.h
>>@@ -162,4 +162,8 @@
>> #define LWIP_ALTCP_TLS_MBEDTLS          1
>> #endif
>> 
>>+#if defined(CONFIG_CMD_SNTP)
>>+#define LWIP_DHCP_GET_NTP_SRV 1
>>+#endif
>>+
>> #endif /* LWIP_UBOOT_LWIPOPTS_H */
>>diff --git a/net/lwip/Makefile b/net/lwip/Makefile
>>index 5df222589b8..5bb98dc4d98 100644
>>--- a/net/lwip/Makefile
>>+++ b/net/lwip/Makefile
>>@@ -4,6 +4,7 @@ obj-$(CONFIG_$(PHASE_)DM_ETH) += net-lwip.o
>> obj-$(CONFIG_CMD_DHCP) += dhcp.o
>> obj-$(CONFIG_CMD_DNS) += dns.o
>> obj-$(CONFIG_CMD_PING) += ping.o
>>+obj-$(CONFIG_CMD_SNTP) += sntp.o
>> obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
>> obj-$(CONFIG_WGET) += wget.o
>> 
>>diff --git a/net/lwip/sntp.c b/net/lwip/sntp.c
>>new file mode 100644
>>index 00000000000..3b2bc3c679d
>>--- /dev/null
>>+++ b/net/lwip/sntp.c
>>@@ -0,0 +1,128 @@
>>+// SPDX-License-Identifier: GPL-2.0+
>>+/* Copyright (C) 2025 Linaro Ltd. */
>>+
>>+#include <command.h>
>>+#include <console.h>
>>+#include <dm/device.h>
>>+#include <lwip/apps/sntp.h>
>>+#include <lwip/timeouts.h>
>>+#include <net.h>
>>+
>>+#define SNTP_TIMEOUT 10000
>>+
>>+static enum done_state {
>>+	NOT_DONE = 0,
>>+	SUCCESS,
>>+	ABORTED,
>>+	TIMED_OUT
>>+} sntp_state;
>>+
>>+static void no_response(void *arg)
>>+{
>>+	sntp_state = TIMED_OUT;
>>+}
>>+
>>+/* Called by lwIP via the SNTP_SET_SYSTEM_TIME() macro */
>>+void sntp_set_system_time(uint32_t seconds)
>>+{
>>+	char *toff;
>>+	int net_ntp_time_offset = 0;
>>+
>>+	toff = env_get("timeoffset");
>>+	if (toff)
>>+		net_ntp_time_offset = simple_strtol(toff, NULL, 10);
>>+
>>+	net_sntp_set_rtc(seconds + net_ntp_time_offset);
>>+	sntp_state = SUCCESS;
>>+}
>>+
>>+static bool ntp_server_known(void)
>>+{
>>+	int i;
>>+
>>+	for (i = 0; i < SNTP_MAX_SERVERS; i++) {
>>+		const ip_addr_t *ip = sntp_getserver(i);
>>+
>>+		if (ip && ip->addr)
>>+			return true;
>>+	}
>>+
>>+	return false;
>>+}
>>+
>>+static int sntp_loop(struct udevice *udev, ip_addr_t *srvip)
>>+{
>>+	struct netif *netif;
>>+
>>+	netif = net_lwip_new_netif(udev);
>>+	if (!netif)
>>+		return -1;
>>+
>>+	sntp_state = NOT_DONE;
>>+
>>+	sntp_setoperatingmode(SNTP_OPMODE_POLL);
>>+	sntp_servermode_dhcp(CONFIG_IS_ENABLED(CMD_DHCP));
>>+	if (srvip) {
>>+		sntp_setserver(0, srvip);
>>+	} else {
>>+		if (!ntp_server_known()) {
>>+			log_err("error: ntpserverip not set\n");
>>+			return -1;
>>+		}
>>+	}
>>+	sntp_init();
>>+
>>+	sys_timeout(SNTP_TIMEOUT, no_response, NULL);
>>+	while (sntp_state == NOT_DONE) {
>>+		net_lwip_rx(udev, netif);
>>+		sys_check_timeouts();
>>+		if (ctrlc()) {
>>+			printf("\nAbort\n");
>>+			sntp_state = ABORTED;
>>+			break;
>>+		}
>>+	}
>>+	sys_untimeout(no_response, NULL);
>>+
>>+	sntp_stop();
>>+	net_lwip_remove_netif(netif);
>>+
>>+	if (sntp_state == SUCCESS)
>>+		return 0;
>>+
>>+	return -1;
>>+}
>>+
>>+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
>>+{
>>+	ip_addr_t *srvip = NULL;
>>+	char *server_ip = NULL;
>>+	ip_addr_t ipaddr;
>>+
>>+	switch (argc) {
>>+	case 1:
>>+		server_ip = env_get("ntpserverip");
>>+		break;
>>+	case 2:
>>+		server_ip = argv[1];
>>+		break;
>>+	default:
>>+		return CMD_RET_USAGE;
>>+	}
>>+
>>+	if (server_ip) {
>>+		if (!ipaddr_aton(server_ip, &ipaddr)) {
>>+			log_err("error: ipaddr_aton\n");
>>+			return CMD_RET_FAILURE;
>>+		}
>>+		srvip = &ipaddr;
>>+	}
>>+
>>+	if (net_lwip_eth_start() < 0)
>>+		return CMD_RET_FAILURE;
>>+
>>+	if (sntp_loop(eth_get_dev(), srvip) < 0)
>>+		return CMD_RET_FAILURE;
>>+
>>+	return CMD_RET_SUCCESS;
>>+}
>
Jerome Forissier June 3, 2025, 1:49 p.m. UTC | #3 
Hi Heinrich,

On 6/2/25 23:23, Heinrich Schuchardt wrote:
> Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
>> Implement the sntp command when NET_LWIP=y.
>>
>> Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
>> ---
>>
>> cmd/Kconfig                |  13 ++--
>> cmd/net-lwip.c             |   5 ++
>> include/net-common.h       |  11 ++++
>> lib/lwip/Makefile          |   1 +
>> lib/lwip/u-boot/arch/cc.h  |   4 ++
>> lib/lwip/u-boot/lwipopts.h |   4 ++
>> net/lwip/Makefile          |   1 +
>> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
>> 8 files changed, 161 insertions(+), 6 deletions(-)
>> create mode 100644 net/lwip/sntp.c
>>
>> diff --git a/cmd/Kconfig b/cmd/Kconfig
>> index f21d27cb27f..58f629e1c34 100644
>> --- a/cmd/Kconfig
>> +++ b/cmd/Kconfig
>> @@ -2061,12 +2061,6 @@ config CMD_CDP
>> 	  and to retrieve configuration data including the VLAN id using the
>> 	  proprietary Cisco Discovery Protocol (CDP).
>>
>> -config CMD_SNTP
>> -	bool "sntp"
>> -	select PROT_UDP
>> -	help
>> -	  Synchronize RTC via network
>> -
>> config CMD_LINK_LOCAL
>> 	bool "linklocal"
>> 	depends on (LIB_RAND || LIB_HW_RAND)
>> @@ -2144,6 +2138,13 @@ config CMD_PING
>> 	help
>> 	  Send ICMP ECHO_REQUEST to network host
>>
>> +config CMD_SNTP
> 
> The command should depend on RTC support.
> 
>> +	bool "sntp"
>> +	select PROT_UDP if NET
>> +	select PROT_UDP_LWIP if NET_LWIP
>> +	help
>> +	  Synchronize RTC via network
>> +
>> config CMD_TFTPBOOT
>> 	bool "tftp"
>> 	select PROT_UDP_LWIP if NET_LWIP
>> diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
>> index cecf8d02555..2ffee64f97e 100644
>> --- a/cmd/net-lwip.c
>> +++ b/cmd/net-lwip.c
> 
> Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.

While I agree that cmd/net.c is painful re. #ifdef's, I believe
cmd/net-lwip.c is not bad at all. In fact I took care of having only the
command wrappers in there (U_BOOT_CMD(...)), so it's just 55 lines at
the moment. The implementations are in
net/lwip/{dhcp,dns,ping,sntp,tftp,wget}.c. So I don't think there is
a need to change that. Or I could move the U_BOOT_CMD(...) into
net/lwip/*.c as well, leaving only the non-net commands under cmd/ (apart
from the legacy NET stuff).

Any opinions on that?


> 
>> @@ -21,6 +21,11 @@ U_BOOT_CMD(tftpboot, 3, 0, do_tftpb,
>> 	   "[loadAddress] [[hostIPaddr:]bootfilename]");
>> #endif
>>
>> +#if defined(CONFIG_CMD_SNTP)
>> +U_BOOT_CMD(sntp, 2, 1, do_sntp, "synchronize RTC via network",
>> +	   "[NTP server IP]");
>> +#endif
> 
> Why wouldn't we support server names ( e.g.  0.de.pool.ntp.org) here if we have DNS enabled?

Good idea. I will add support for server names to v2.

> 
> Please, add the missing documentation change for the commands.

Sure.

> Best regards
> 
> Heinrich
> 
> 
>> +
>> #if defined(CONFIG_CMD_DNS)
>> U_BOOT_CMD(dns, 3, 1, do_dns, "lookup the IP of a hostname",
>> 	   "hostname [envvar]");
>> diff --git a/include/net-common.h b/include/net-common.h
>> index a021bf503ff..b06cafb497e 100644
>> --- a/include/net-common.h
>> +++ b/include/net-common.h
>> @@ -505,6 +505,17 @@ int dhcp_run(ulong addr, const char *fname, bool autoload);
>>  */
>> int do_ping(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
>>
>> +/**
>> + * do_sntp - Run the sntp command
>> + *
>> + * @cmdtp: Unused
>> + * @flag: Command flags (CMD_FLAG_...)
>> + * @argc: Number of arguments
>> + * @argv: List of arguments
>> + * Return: result (see enum command_ret_t)
>> + */
>> +int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
>> +
>> /**
>>  * do_tftpb - Run the tftpboot command
>>  *
>> diff --git a/lib/lwip/Makefile b/lib/lwip/Makefile
>> index e9e8caee93a..c3f0e916f66 100644
>> --- a/lib/lwip/Makefile
>> +++ b/lib/lwip/Makefile
>> @@ -13,6 +13,7 @@ obj-y += \
>> 	lwip/src/api/sockets.o \
>> 	lwip/src/api/tcpip.o \
>> 	lwip/src/apps/http/http_client.o \
>> +	lwip/src/apps/sntp/sntp.o \
>> 	lwip/src/apps/tftp/tftp.o \
>> 	lwip/src/core/altcp_alloc.o \
>> 	lwip/src/core/altcp.o \
>> diff --git a/lib/lwip/u-boot/arch/cc.h b/lib/lwip/u-boot/arch/cc.h
>> index 6104c296f6f..f91127ac565 100644
>> --- a/lib/lwip/u-boot/arch/cc.h
>> +++ b/lib/lwip/u-boot/arch/cc.h
>> @@ -43,4 +43,8 @@
>> #define BYTE_ORDER BIG_ENDIAN
>> #endif
>>
>> +#define SNTP_STARTUP_DELAY 0
>> +void sntp_set_system_time(uint32_t sec);
>> +#define SNTP_SET_SYSTEM_TIME(sec) sntp_set_system_time(sec)
>> +
>> #endif /* LWIP_ARCH_CC_H */
>> diff --git a/lib/lwip/u-boot/lwipopts.h b/lib/lwip/u-boot/lwipopts.h
>> index edac74ff7a2..14ba7bd7ae2 100644
>> --- a/lib/lwip/u-boot/lwipopts.h
>> +++ b/lib/lwip/u-boot/lwipopts.h
>> @@ -162,4 +162,8 @@
>> #define LWIP_ALTCP_TLS_MBEDTLS          1
>> #endif
>>
>> +#if defined(CONFIG_CMD_SNTP)
>> +#define LWIP_DHCP_GET_NTP_SRV 1
>> +#endif
>> +
>> #endif /* LWIP_UBOOT_LWIPOPTS_H */
>> diff --git a/net/lwip/Makefile b/net/lwip/Makefile
>> index 5df222589b8..5bb98dc4d98 100644
>> --- a/net/lwip/Makefile
>> +++ b/net/lwip/Makefile
>> @@ -4,6 +4,7 @@ obj-$(CONFIG_$(PHASE_)DM_ETH) += net-lwip.o
>> obj-$(CONFIG_CMD_DHCP) += dhcp.o
>> obj-$(CONFIG_CMD_DNS) += dns.o
>> obj-$(CONFIG_CMD_PING) += ping.o
>> +obj-$(CONFIG_CMD_SNTP) += sntp.o
>> obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
>> obj-$(CONFIG_WGET) += wget.o
>>
>> diff --git a/net/lwip/sntp.c b/net/lwip/sntp.c
>> new file mode 100644
>> index 00000000000..3b2bc3c679d
>> --- /dev/null
>> +++ b/net/lwip/sntp.c
>> @@ -0,0 +1,128 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/* Copyright (C) 2025 Linaro Ltd. */
>> +
>> +#include <command.h>
>> +#include <console.h>
>> +#include <dm/device.h>
>> +#include <lwip/apps/sntp.h>
>> +#include <lwip/timeouts.h>
>> +#include <net.h>
>> +
>> +#define SNTP_TIMEOUT 10000
>> +
>> +static enum done_state {
>> +	NOT_DONE = 0,
>> +	SUCCESS,
>> +	ABORTED,
>> +	TIMED_OUT
>> +} sntp_state;
>> +
>> +static void no_response(void *arg)
>> +{
>> +	sntp_state = TIMED_OUT;
>> +}
>> +
>> +/* Called by lwIP via the SNTP_SET_SYSTEM_TIME() macro */
>> +void sntp_set_system_time(uint32_t seconds)
>> +{
>> +	char *toff;
>> +	int net_ntp_time_offset = 0;
>> +
>> +	toff = env_get("timeoffset");
>> +	if (toff)
>> +		net_ntp_time_offset = simple_strtol(toff, NULL, 10);
>> +
>> +	net_sntp_set_rtc(seconds + net_ntp_time_offset);
>> +	sntp_state = SUCCESS;
>> +}
>> +
>> +static bool ntp_server_known(void)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < SNTP_MAX_SERVERS; i++) {
>> +		const ip_addr_t *ip = sntp_getserver(i);
>> +
>> +		if (ip && ip->addr)
>> +			return true;
>> +	}
>> +
>> +	return false;
>> +}
>> +
>> +static int sntp_loop(struct udevice *udev, ip_addr_t *srvip)
>> +{
>> +	struct netif *netif;
>> +
>> +	netif = net_lwip_new_netif(udev);
>> +	if (!netif)
>> +		return -1;
>> +
>> +	sntp_state = NOT_DONE;
>> +
>> +	sntp_setoperatingmode(SNTP_OPMODE_POLL);
>> +	sntp_servermode_dhcp(CONFIG_IS_ENABLED(CMD_DHCP));
>> +	if (srvip) {
>> +		sntp_setserver(0, srvip);
>> +	} else {
>> +		if (!ntp_server_known()) {
>> +			log_err("error: ntpserverip not set\n");
>> +			return -1;
>> +		}
>> +	}
>> +	sntp_init();
>> +
>> +	sys_timeout(SNTP_TIMEOUT, no_response, NULL);
>> +	while (sntp_state == NOT_DONE) {
>> +		net_lwip_rx(udev, netif);
>> +		sys_check_timeouts();
>> +		if (ctrlc()) {
>> +			printf("\nAbort\n");
>> +			sntp_state = ABORTED;
>> +			break;
>> +		}
>> +	}
>> +	sys_untimeout(no_response, NULL);
>> +
>> +	sntp_stop();
>> +	net_lwip_remove_netif(netif);
>> +
>> +	if (sntp_state == SUCCESS)
>> +		return 0;
>> +
>> +	return -1;
>> +}
>> +
>> +int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
>> +{
>> +	ip_addr_t *srvip = NULL;
>> +	char *server_ip = NULL;
>> +	ip_addr_t ipaddr;
>> +
>> +	switch (argc) {
>> +	case 1:
>> +		server_ip = env_get("ntpserverip");
>> +		break;
>> +	case 2:
>> +		server_ip = argv[1];
>> +		break;
>> +	default:
>> +		return CMD_RET_USAGE;
>> +	}
>> +
>> +	if (server_ip) {
>> +		if (!ipaddr_aton(server_ip, &ipaddr)) {
>> +			log_err("error: ipaddr_aton\n");
>> +			return CMD_RET_FAILURE;
>> +		}
>> +		srvip = &ipaddr;
>> +	}
>> +
>> +	if (net_lwip_eth_start() < 0)
>> +		return CMD_RET_FAILURE;
>> +
>> +	if (sntp_loop(eth_get_dev(), srvip) < 0)
>> +		return CMD_RET_FAILURE;
>> +
>> +	return CMD_RET_SUCCESS;
>> +}
>
Tom Rini June 3, 2025, 2:06 p.m. UTC | #4 
On Tue, Jun 03, 2025 at 03:49:05PM +0200, Jerome Forissier wrote:
> Hi Heinrich,
> 
> On 6/2/25 23:23, Heinrich Schuchardt wrote:
> > Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
> >> Implement the sntp command when NET_LWIP=y.
> >>
> >> Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
> >> ---
> >>
> >> cmd/Kconfig                |  13 ++--
> >> cmd/net-lwip.c             |   5 ++
> >> include/net-common.h       |  11 ++++
> >> lib/lwip/Makefile          |   1 +
> >> lib/lwip/u-boot/arch/cc.h  |   4 ++
> >> lib/lwip/u-boot/lwipopts.h |   4 ++
> >> net/lwip/Makefile          |   1 +
> >> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
> >> 8 files changed, 161 insertions(+), 6 deletions(-)
> >> create mode 100644 net/lwip/sntp.c
> >>
> >> diff --git a/cmd/Kconfig b/cmd/Kconfig
> >> index f21d27cb27f..58f629e1c34 100644
> >> --- a/cmd/Kconfig
> >> +++ b/cmd/Kconfig
> >> @@ -2061,12 +2061,6 @@ config CMD_CDP
> >> 	  and to retrieve configuration data including the VLAN id using the
> >> 	  proprietary Cisco Discovery Protocol (CDP).
> >>
> >> -config CMD_SNTP
> >> -	bool "sntp"
> >> -	select PROT_UDP
> >> -	help
> >> -	  Synchronize RTC via network
> >> -
> >> config CMD_LINK_LOCAL
> >> 	bool "linklocal"
> >> 	depends on (LIB_RAND || LIB_HW_RAND)
> >> @@ -2144,6 +2138,13 @@ config CMD_PING
> >> 	help
> >> 	  Send ICMP ECHO_REQUEST to network host
> >>
> >> +config CMD_SNTP
> > 
> > The command should depend on RTC support.
> > 
> >> +	bool "sntp"
> >> +	select PROT_UDP if NET
> >> +	select PROT_UDP_LWIP if NET_LWIP
> >> +	help
> >> +	  Synchronize RTC via network
> >> +
> >> config CMD_TFTPBOOT
> >> 	bool "tftp"
> >> 	select PROT_UDP_LWIP if NET_LWIP
> >> diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
> >> index cecf8d02555..2ffee64f97e 100644
> >> --- a/cmd/net-lwip.c
> >> +++ b/cmd/net-lwip.c
> > 
> > Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.
> 
> While I agree that cmd/net.c is painful re. #ifdef's, I believe
> cmd/net-lwip.c is not bad at all. In fact I took care of having only the
> command wrappers in there (U_BOOT_CMD(...)), so it's just 55 lines at
> the moment. The implementations are in
> net/lwip/{dhcp,dns,ping,sntp,tftp,wget}.c. So I don't think there is
> a need to change that. Or I could move the U_BOOT_CMD(...) into
> net/lwip/*.c as well, leaving only the non-net commands under cmd/ (apart
> from the legacy NET stuff).
> 
> Any opinions on that?

While there are commands outside of cmd/ they are the exception (and
generally ought to be moved) so if we go the route of breaking up
cmd/net-lwip.c I'd rather see cmd/lwip/${cmd}.c instead.
Jerome Forissier June 3, 2025, 2:13 p.m. UTC | #5 
On 6/3/25 16:06, Tom Rini wrote:
> On Tue, Jun 03, 2025 at 03:49:05PM +0200, Jerome Forissier wrote:
>> Hi Heinrich,
>>
>> On 6/2/25 23:23, Heinrich Schuchardt wrote:
>>> Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
>>>> Implement the sntp command when NET_LWIP=y.
>>>>
>>>> Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
>>>> ---
>>>>
>>>> cmd/Kconfig                |  13 ++--
>>>> cmd/net-lwip.c             |   5 ++
>>>> include/net-common.h       |  11 ++++
>>>> lib/lwip/Makefile          |   1 +
>>>> lib/lwip/u-boot/arch/cc.h  |   4 ++
>>>> lib/lwip/u-boot/lwipopts.h |   4 ++
>>>> net/lwip/Makefile          |   1 +
>>>> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
>>>> 8 files changed, 161 insertions(+), 6 deletions(-)
>>>> create mode 100644 net/lwip/sntp.c
>>>>
>>>> diff --git a/cmd/Kconfig b/cmd/Kconfig
>>>> index f21d27cb27f..58f629e1c34 100644
>>>> --- a/cmd/Kconfig
>>>> +++ b/cmd/Kconfig
>>>> @@ -2061,12 +2061,6 @@ config CMD_CDP
>>>> 	  and to retrieve configuration data including the VLAN id using the
>>>> 	  proprietary Cisco Discovery Protocol (CDP).
>>>>
>>>> -config CMD_SNTP
>>>> -	bool "sntp"
>>>> -	select PROT_UDP
>>>> -	help
>>>> -	  Synchronize RTC via network
>>>> -
>>>> config CMD_LINK_LOCAL
>>>> 	bool "linklocal"
>>>> 	depends on (LIB_RAND || LIB_HW_RAND)
>>>> @@ -2144,6 +2138,13 @@ config CMD_PING
>>>> 	help
>>>> 	  Send ICMP ECHO_REQUEST to network host
>>>>
>>>> +config CMD_SNTP
>>>
>>> The command should depend on RTC support.
>>>
>>>> +	bool "sntp"
>>>> +	select PROT_UDP if NET
>>>> +	select PROT_UDP_LWIP if NET_LWIP
>>>> +	help
>>>> +	  Synchronize RTC via network
>>>> +
>>>> config CMD_TFTPBOOT
>>>> 	bool "tftp"
>>>> 	select PROT_UDP_LWIP if NET_LWIP
>>>> diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
>>>> index cecf8d02555..2ffee64f97e 100644
>>>> --- a/cmd/net-lwip.c
>>>> +++ b/cmd/net-lwip.c
>>>
>>> Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.
>>
>> While I agree that cmd/net.c is painful re. #ifdef's, I believe
>> cmd/net-lwip.c is not bad at all. In fact I took care of having only the
>> command wrappers in there (U_BOOT_CMD(...)), so it's just 55 lines at
>> the moment. The implementations are in
>> net/lwip/{dhcp,dns,ping,sntp,tftp,wget}.c. So I don't think there is
>> a need to change that. Or I could move the U_BOOT_CMD(...) into
>> net/lwip/*.c as well, leaving only the non-net commands under cmd/ (apart
>> from the legacy NET stuff).
>>
>> Any opinions on that?
> 
> While there are commands outside of cmd/ they are the exception (and
> generally ought to be moved) so if we go the route of breaking up
> cmd/net-lwip.c I'd rather see cmd/lwip/${cmd}.c instead.

To be clear, you mean moving net/lwip/${cmd}.c into cmd/lwip/ in addition to
splitting cmd/net-lwip.c?

Thanks,
Tom Rini June 3, 2025, 2:19 p.m. UTC | #6 
On Tue, Jun 03, 2025 at 04:13:32PM +0200, Jerome Forissier wrote:
> 
> 
> On 6/3/25 16:06, Tom Rini wrote:
> > On Tue, Jun 03, 2025 at 03:49:05PM +0200, Jerome Forissier wrote:
> >> Hi Heinrich,
> >>
> >> On 6/2/25 23:23, Heinrich Schuchardt wrote:
> >>> Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
> >>>> Implement the sntp command when NET_LWIP=y.
> >>>>
> >>>> Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
> >>>> ---
> >>>>
> >>>> cmd/Kconfig                |  13 ++--
> >>>> cmd/net-lwip.c             |   5 ++
> >>>> include/net-common.h       |  11 ++++
> >>>> lib/lwip/Makefile          |   1 +
> >>>> lib/lwip/u-boot/arch/cc.h  |   4 ++
> >>>> lib/lwip/u-boot/lwipopts.h |   4 ++
> >>>> net/lwip/Makefile          |   1 +
> >>>> net/lwip/sntp.c            | 128 +++++++++++++++++++++++++++++++++++++
> >>>> 8 files changed, 161 insertions(+), 6 deletions(-)
> >>>> create mode 100644 net/lwip/sntp.c
> >>>>
> >>>> diff --git a/cmd/Kconfig b/cmd/Kconfig
> >>>> index f21d27cb27f..58f629e1c34 100644
> >>>> --- a/cmd/Kconfig
> >>>> +++ b/cmd/Kconfig
> >>>> @@ -2061,12 +2061,6 @@ config CMD_CDP
> >>>> 	  and to retrieve configuration data including the VLAN id using the
> >>>> 	  proprietary Cisco Discovery Protocol (CDP).
> >>>>
> >>>> -config CMD_SNTP
> >>>> -	bool "sntp"
> >>>> -	select PROT_UDP
> >>>> -	help
> >>>> -	  Synchronize RTC via network
> >>>> -
> >>>> config CMD_LINK_LOCAL
> >>>> 	bool "linklocal"
> >>>> 	depends on (LIB_RAND || LIB_HW_RAND)
> >>>> @@ -2144,6 +2138,13 @@ config CMD_PING
> >>>> 	help
> >>>> 	  Send ICMP ECHO_REQUEST to network host
> >>>>
> >>>> +config CMD_SNTP
> >>>
> >>> The command should depend on RTC support.
> >>>
> >>>> +	bool "sntp"
> >>>> +	select PROT_UDP if NET
> >>>> +	select PROT_UDP_LWIP if NET_LWIP
> >>>> +	help
> >>>> +	  Synchronize RTC via network
> >>>> +
> >>>> config CMD_TFTPBOOT
> >>>> 	bool "tftp"
> >>>> 	select PROT_UDP_LWIP if NET_LWIP
> >>>> diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
> >>>> index cecf8d02555..2ffee64f97e 100644
> >>>> --- a/cmd/net-lwip.c
> >>>> +++ b/cmd/net-lwip.c
> >>>
> >>> Please, put every command into a separate file instead of duplicating the #ifdef chaos of the old network stack.
> >>
> >> While I agree that cmd/net.c is painful re. #ifdef's, I believe
> >> cmd/net-lwip.c is not bad at all. In fact I took care of having only the
> >> command wrappers in there (U_BOOT_CMD(...)), so it's just 55 lines at
> >> the moment. The implementations are in
> >> net/lwip/{dhcp,dns,ping,sntp,tftp,wget}.c. So I don't think there is
> >> a need to change that. Or I could move the U_BOOT_CMD(...) into
> >> net/lwip/*.c as well, leaving only the non-net commands under cmd/ (apart
> >> from the legacy NET stuff).
> >>
> >> Any opinions on that?
> > 
> > While there are commands outside of cmd/ they are the exception (and
> > generally ought to be moved) so if we go the route of breaking up
> > cmd/net-lwip.c I'd rather see cmd/lwip/${cmd}.c instead.
> 
> To be clear, you mean moving net/lwip/${cmd}.c into cmd/lwip/ in addition to
> splitting cmd/net-lwip.c?

Yes and I think that will make things clearer overall, thanks.
Jerome Forissier June 3, 2025, 2:27 p.m. UTC | #7 
On 6/3/25 07:51, Heinrich Schuchardt wrote:
> Am 2. Juni 2025 23:23:08 MESZ schrieb Heinrich Schuchardt <xypron.glpk@gmx.de>:
>> Am 21. Mai 2025 17:14:42 MESZ schrieb Jerome Forissier <jerome.forissier@linaro.org>:
>>> Implement the sntp command when NET_LWIP=y.
> 
> https://datatracker.ietf.org/doc/rfc5905/ describes that on Feb 7th, 2036 the 32 bit seconds field wraps around and era 1 starts.
> 
> Does our code consider this?

I don't know. The lwIP code seems to somewhat take care of the year 2036
issue [1] but I need to spend more time understanding what's happening
here to be certain.

[1] https://github.com/u-boot/u-boot/blob/d1555de5fa21c06118540dcd4a627a1af29bbb40/lib/lwip/lwip/src/apps/sntp/sntp.c#L141

Thanks,
diff mbox series

Patch

diff --git a/cmd/Kconfig b/cmd/Kconfig
index f21d27cb27f..58f629e1c34 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -2061,12 +2061,6 @@  config CMD_CDP
 	  and to retrieve configuration data including the VLAN id using the
 	  proprietary Cisco Discovery Protocol (CDP).
 
-config CMD_SNTP
-	bool "sntp"
-	select PROT_UDP
-	help
-	  Synchronize RTC via network
-
 config CMD_LINK_LOCAL
 	bool "linklocal"
 	depends on (LIB_RAND || LIB_HW_RAND)
@@ -2144,6 +2138,13 @@  config CMD_PING
 	help
 	  Send ICMP ECHO_REQUEST to network host
 
+config CMD_SNTP
+	bool "sntp"
+	select PROT_UDP if NET
+	select PROT_UDP_LWIP if NET_LWIP
+	help
+	  Synchronize RTC via network
+
 config CMD_TFTPBOOT
 	bool "tftp"
 	select PROT_UDP_LWIP if NET_LWIP
diff --git a/cmd/net-lwip.c b/cmd/net-lwip.c
index cecf8d02555..2ffee64f97e 100644
--- a/cmd/net-lwip.c
+++ b/cmd/net-lwip.c
@@ -21,6 +21,11 @@  U_BOOT_CMD(tftpboot, 3, 0, do_tftpb,
 	   "[loadAddress] [[hostIPaddr:]bootfilename]");
 #endif
 
+#if defined(CONFIG_CMD_SNTP)
+U_BOOT_CMD(sntp, 2, 1, do_sntp, "synchronize RTC via network",
+	   "[NTP server IP]");
+#endif
+
 #if defined(CONFIG_CMD_DNS)
 U_BOOT_CMD(dns, 3, 1, do_dns, "lookup the IP of a hostname",
 	   "hostname [envvar]");
diff --git a/include/net-common.h b/include/net-common.h
index a021bf503ff..b06cafb497e 100644
--- a/include/net-common.h
+++ b/include/net-common.h
@@ -505,6 +505,17 @@  int dhcp_run(ulong addr, const char *fname, bool autoload);
  */
 int do_ping(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
 
+/**
+ * do_sntp - Run the sntp command
+ *
+ * @cmdtp: Unused
+ * @flag: Command flags (CMD_FLAG_...)
+ * @argc: Number of arguments
+ * @argv: List of arguments
+ * Return: result (see enum command_ret_t)
+ */
+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]);
+
 /**
  * do_tftpb - Run the tftpboot command
  *
diff --git a/lib/lwip/Makefile b/lib/lwip/Makefile
index e9e8caee93a..c3f0e916f66 100644
--- a/lib/lwip/Makefile
+++ b/lib/lwip/Makefile
@@ -13,6 +13,7 @@  obj-y += \
 	lwip/src/api/sockets.o \
 	lwip/src/api/tcpip.o \
 	lwip/src/apps/http/http_client.o \
+	lwip/src/apps/sntp/sntp.o \
 	lwip/src/apps/tftp/tftp.o \
 	lwip/src/core/altcp_alloc.o \
 	lwip/src/core/altcp.o \
diff --git a/lib/lwip/u-boot/arch/cc.h b/lib/lwip/u-boot/arch/cc.h
index 6104c296f6f..f91127ac565 100644
--- a/lib/lwip/u-boot/arch/cc.h
+++ b/lib/lwip/u-boot/arch/cc.h
@@ -43,4 +43,8 @@ 
 #define BYTE_ORDER BIG_ENDIAN
 #endif
 
+#define SNTP_STARTUP_DELAY 0
+void sntp_set_system_time(uint32_t sec);
+#define SNTP_SET_SYSTEM_TIME(sec) sntp_set_system_time(sec)
+
 #endif /* LWIP_ARCH_CC_H */
diff --git a/lib/lwip/u-boot/lwipopts.h b/lib/lwip/u-boot/lwipopts.h
index edac74ff7a2..14ba7bd7ae2 100644
--- a/lib/lwip/u-boot/lwipopts.h
+++ b/lib/lwip/u-boot/lwipopts.h
@@ -162,4 +162,8 @@ 
 #define LWIP_ALTCP_TLS_MBEDTLS          1
 #endif
 
+#if defined(CONFIG_CMD_SNTP)
+#define LWIP_DHCP_GET_NTP_SRV 1
+#endif
+
 #endif /* LWIP_UBOOT_LWIPOPTS_H */
diff --git a/net/lwip/Makefile b/net/lwip/Makefile
index 5df222589b8..5bb98dc4d98 100644
--- a/net/lwip/Makefile
+++ b/net/lwip/Makefile
@@ -4,6 +4,7 @@  obj-$(CONFIG_$(PHASE_)DM_ETH) += net-lwip.o
 obj-$(CONFIG_CMD_DHCP) += dhcp.o
 obj-$(CONFIG_CMD_DNS) += dns.o
 obj-$(CONFIG_CMD_PING) += ping.o
+obj-$(CONFIG_CMD_SNTP) += sntp.o
 obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
 obj-$(CONFIG_WGET) += wget.o
 
diff --git a/net/lwip/sntp.c b/net/lwip/sntp.c
new file mode 100644
index 00000000000..3b2bc3c679d
--- /dev/null
+++ b/net/lwip/sntp.c
@@ -0,0 +1,128 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2025 Linaro Ltd. */
+
+#include <command.h>
+#include <console.h>
+#include <dm/device.h>
+#include <lwip/apps/sntp.h>
+#include <lwip/timeouts.h>
+#include <net.h>
+
+#define SNTP_TIMEOUT 10000
+
+static enum done_state {
+	NOT_DONE = 0,
+	SUCCESS,
+	ABORTED,
+	TIMED_OUT
+} sntp_state;
+
+static void no_response(void *arg)
+{
+	sntp_state = TIMED_OUT;
+}
+
+/* Called by lwIP via the SNTP_SET_SYSTEM_TIME() macro */
+void sntp_set_system_time(uint32_t seconds)
+{
+	char *toff;
+	int net_ntp_time_offset = 0;
+
+	toff = env_get("timeoffset");
+	if (toff)
+		net_ntp_time_offset = simple_strtol(toff, NULL, 10);
+
+	net_sntp_set_rtc(seconds + net_ntp_time_offset);
+	sntp_state = SUCCESS;
+}
+
+static bool ntp_server_known(void)
+{
+	int i;
+
+	for (i = 0; i < SNTP_MAX_SERVERS; i++) {
+		const ip_addr_t *ip = sntp_getserver(i);
+
+		if (ip && ip->addr)
+			return true;
+	}
+
+	return false;
+}
+
+static int sntp_loop(struct udevice *udev, ip_addr_t *srvip)
+{
+	struct netif *netif;
+
+	netif = net_lwip_new_netif(udev);
+	if (!netif)
+		return -1;
+
+	sntp_state = NOT_DONE;
+
+	sntp_setoperatingmode(SNTP_OPMODE_POLL);
+	sntp_servermode_dhcp(CONFIG_IS_ENABLED(CMD_DHCP));
+	if (srvip) {
+		sntp_setserver(0, srvip);
+	} else {
+		if (!ntp_server_known()) {
+			log_err("error: ntpserverip not set\n");
+			return -1;
+		}
+	}
+	sntp_init();
+
+	sys_timeout(SNTP_TIMEOUT, no_response, NULL);
+	while (sntp_state == NOT_DONE) {
+		net_lwip_rx(udev, netif);
+		sys_check_timeouts();
+		if (ctrlc()) {
+			printf("\nAbort\n");
+			sntp_state = ABORTED;
+			break;
+		}
+	}
+	sys_untimeout(no_response, NULL);
+
+	sntp_stop();
+	net_lwip_remove_netif(netif);
+
+	if (sntp_state == SUCCESS)
+		return 0;
+
+	return -1;
+}
+
+int do_sntp(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
+{
+	ip_addr_t *srvip = NULL;
+	char *server_ip = NULL;
+	ip_addr_t ipaddr;
+
+	switch (argc) {
+	case 1:
+		server_ip = env_get("ntpserverip");
+		break;
+	case 2:
+		server_ip = argv[1];
+		break;
+	default:
+		return CMD_RET_USAGE;
+	}
+
+	if (server_ip) {
+		if (!ipaddr_aton(server_ip, &ipaddr)) {
+			log_err("error: ipaddr_aton\n");
+			return CMD_RET_FAILURE;
+		}
+		srvip = &ipaddr;
+	}
+
+	if (net_lwip_eth_start() < 0)
+		return CMD_RET_FAILURE;
+
+	if (sntp_loop(eth_get_dev(), srvip) < 0)
+		return CMD_RET_FAILURE;
+
+	return CMD_RET_SUCCESS;
+}