net: Add a function to run dhcp

At present this must be done by executing the command. Also it involves
fiddling with the environment to determine the correct autoload behaviour.

Ideally it should be possible to run network operations without even
having the command line present (CONFIG_CMDLINE).

For now, add a function to handle DHCP, so it can be called from a bootdev
more easily.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/cmd/net.c b/cmd/net.c
index dd50930a36..4227321871 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -4,6 +4,8 @@
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  */
 
+#define LOG_CATEGORY	UCLASS_ETH
+
 /*
  * Boot support
  */
@@ -13,6 +15,7 @@
 #include <dm.h>
 #include <env.h>
 #include <image.h>
+#include <log.h>
 #include <net.h>
 #include <net6.h>
 #include <net/udp.h>
@@ -120,6 +123,38 @@ U_BOOT_CMD(
 	"boot image via network using DHCP/TFTP protocol",
 	"[loadAddress] [[hostIPaddr:]bootfilename]"
 );
+
+int dhcp_run(ulong addr, const char *fname, bool autoload)
+{
+	char *dhcp_argv[] = {"dhcp", NULL, (char *)fname, NULL};
+	struct cmd_tbl cmdtp = {};	/* dummy */
+	char file_addr[17];
+	int old_autoload;
+	int ret, result;
+
+	log_debug("addr=%lx, fname=%s, autoload=%d\n", addr, fname, autoload);
+	old_autoload = env_get_yesno("autoload");
+	ret = env_set("autoload", autoload ? "y" : "n");
+	if (ret)
+		return log_msg_ret("en1", -EINVAL);
+
+	if (autoload) {
+		sprintf(file_addr, "%lx", addr);
+		dhcp_argv[1] = file_addr;
+	}
+
+	result = do_dhcp(&cmdtp, 0, !autoload ? 1 : fname ? 3 : 2, dhcp_argv);
+
+	ret = env_set("autoload", old_autoload == -1 ? NULL :
+		      old_autoload ? "y" : "n");
+	if (ret)
+		return log_msg_ret("en2", -EINVAL);
+
+	if (result)
+		return log_msg_ret("res", -ENOENT);
+
+	return 0;
+}
 #endif
 
 #if defined(CONFIG_CMD_NFS)