Subject: [PATCH] ethtool: Support arbitrary speeds

From: Ben Hutchings <[email-masked]>
Date: Fri, 09 Jan 2009 13:16:14 +0000

The speed and speed_hi fields of struct ethtool_cmd together represent
a value in units of Mbit/s.  The valid speed settings are hardware-
dependent and should be checked by the driver.  Remove our validation
and allow arbitrary positive values.  Continue to report 0 and -1 as
"Unknown!" since some drivers will report these invalid values when
the link is down.

Signed-off-by: Ben Hutchings <[email-masked]>
---
On Thu, 2009-01-08 at 11:50 -0800, Rick Jones wrote:
> > 
> > I think 0, (u32)(-1) and (u16)(-1) may have to be special-cased as
> > unknown, but everything else can be treated as a number of Mbit/s.  I
> > don't know what a driver should do about an interface that really runs
> > at 65.535 Gbit/s though...
> 
> Something along these lines then? (assuming my mailer doesn't fubar this
> :( - I normally send matches via mailx)

That's kind of incomplete.  Here's my attempt.

In a quick test I found that the tg3 driver *doesn't* validate the speed
setting if autonegotiation is off, and will accept and report back e.g.
99.  But this patch doesn't create a new problem as you could already
set it to the unsupported speeds of 2500 and 10000.

Ben.

 ethtool.8 |    4 ++--
 ethtool.c |   42 ++++++++++--------------------------------
 2 files changed, 12 insertions(+), 34 deletions(-)

diff --git a/ethtool.8 b/ethtool.8
index 1beb387..1504a23 100644
--- a/ethtool.8
+++ b/ethtool.8
@@ -183,7 +183,7 @@ ethtool \- Display or change ethernet card settings
 
 .B ethtool \-s
 .I ethX
-.B4 speed 10 100 1000 2500 10000
+.BI speed \ N
 .B2 duplex half full
 .B4 port tp aui bnc mii fibre
 .B2 autoneg on off
@@ -343,7 +343,7 @@ All following options only apply if
 .B \-s
 was specified.
 .TP
-.A4 speed 10 100 1000 2500 10000
+.BI speed \ N
 Set speed in Mb/s.
 .B ethtool
 with just the device name as an argument will show you the supported device speeds.
diff --git a/ethtool.c b/ethtool.c
index a7c02d0..bcc865e 100644
--- a/ethtool.c
+++ b/ethtool.c
@@ -107,7 +107,7 @@ static struct option {
     char *opthelp;
 } args[] = {
     { "-s", "--change", MODE_SSET, "Change generic options",
-		"		[ speed 10|100|1000|2500|10000 ]\n"
+		"		[ speed %%d ]\n"
 		"		[ duplex half|full ]\n"
 		"		[ port tp|aui|bnc|mii|fibre ]\n"
 		"		[ autoneg on|off ]\n"
@@ -608,17 +608,8 @@ static void parse_cmdline(int argc, char **argp)
 				i += 1;
 				if (i >= argc)
 					show_usage(1);
-				if (!strcmp(argp[i], "10"))
-					speed_wanted = SPEED_10;
-				else if (!strcmp(argp[i], "100"))
-					speed_wanted = SPEED_100;
-				else if (!strcmp(argp[i], "1000"))
-					speed_wanted = SPEED_1000;
-				else if (!strcmp(argp[i], "2500"))
-					speed_wanted = SPEED_2500;
-				else if (!strcmp(argp[i], "10000"))
-					speed_wanted = SPEED_10000;
-				else
+				speed_wanted = strtol(argp[i], NULL, 10);
+				if (speed_wanted <= 0)
 					show_usage(1);
 				break;
 			} else if (!strcmp(argp[i], "duplex")) {
@@ -893,30 +884,17 @@ static void dump_advertised(struct ethtool_cmd *ep)
 
 static int dump_ecmd(struct ethtool_cmd *ep)
 {
+	u32 speed;
+
 	dump_supported(ep);
 	dump_advertised(ep);
 
 	fprintf(stdout, "	Speed: ");
-	switch (ethtool_cmd_speed(ep)) {
-	case SPEED_10:
-		fprintf(stdout, "10Mb/s\n");
-		break;
-	case SPEED_100:
-		fprintf(stdout, "100Mb/s\n");
-		break;
-	case SPEED_1000:
-		fprintf(stdout, "1000Mb/s\n");
-		break;
-	case SPEED_2500:
-		fprintf(stdout, "2500Mb/s\n");
-		break;
-	case SPEED_10000:
-		fprintf(stdout, "10000Mb/s\n");
-		break;
-	default:
-		fprintf(stdout, "Unknown! (%i)\n", ethtool_cmd_speed(ep));
-		break;
-	};
+	speed = ethtool_cmd_speed(ep);
+	if (speed == 0 || speed == (u16)(-1) || speed == (u32)(-1))
+		fprintf(stdout, "Unknown!\n");
+	else
+		fprintf(stdout, "%uMb/s\n", speed);
 
 	fprintf(stdout, "	Duplex: ");
 	switch (ep->duplex) {

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.