diff mbox

Make auto-loading of therm_pm72 possible

Message ID 1291561537-1943-1-git-send-email-maz@misterjones.org (mailing list archive)
State Accepted, archived
Commit 98b14d6b290d96b24ae993ceaccc59b2aa4b130c
Delegated to: Benjamin Herrenschmidt
Headers show

Commit Message

Marc Zyngier Dec. 5, 2010, 3:05 p.m. UTC 
The therm_pm72 driver, used on the PowerMac G5 range, cannot be
auto-loaded, since the driver itself creates both the device node
and the driver instance.

Moving the device node creation to the platform setup code and
adding the necessary MODULE_DEVICE_TABLE() information allows the
driver to be automatically loaded by udev on any semi-modern
distribution.

It "fixes" a major source of problem on G5 machines where the
driver wasn't explicitely loaded by default, and the system
would automatically shutdown under load.

Tested on an Xserve G5.

Signed-off-by: Marc Zyngier <maz@misterjones.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
 arch/powerpc/platforms/powermac/setup.c |    9 +++++++++
 drivers/macintosh/therm_pm72.c          |   30 +++++-------------------------
 2 files changed, 14 insertions(+), 25 deletions(-)

Comments

kevin diggs Dec. 6, 2010, 6:25 p.m. UTC | #1 
Hi,

On a sort of related issue, if anyone out there has a PowerMac7,3
(dual 2.5 GHz 970Fx, PCI-X), I would appreciate it if you could do me
a favor.

I think this therm_pm72 thing creates the sysfs temperature and
voltage attributes for the cpus. I noticed on my machine that if I use
the cpufreq driver for this thing the frequencies were like 2.0 and
2.5. The problem is that the cpu voltages were something like 1.25 and
1.37 respectively. At 1.37 and 2.5 GHz, cpu 1 would zoom to 110+ under
load.

When I finally managed to get a compiler built that could build a
kernel past 2.6.28, I removed the cpufreq driver. Now this thing runs
at 2.5 GHz all the time. Under load cpu1 tops out at like 74 ish. I
eventually noticed that the voltage was 1.25. Huh? I thought this
voltage scaling business used the high voltage for the high frequency.
How can this thing be running at its high speed at the lower
voltage???

Can someone please confirm this behavior on a different 7,3? I did get
this thing off of ebay and might have myself a franken G5?

Thanks!

kevin

P.S.:  I also don't get the 2.0 GHz low speed? I thought with the FX
the speed would be 2.5 / 2 or 1.25? Does this beast NOT use the FX's
frequency scaling capabilities?
diff mbox

Patch

diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index 9deb274..d5aceb7 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -506,6 +506,15 @@  static int __init pmac_declare_of_platform_devices(void)
 		of_platform_device_create(np, "smu", NULL);
 		of_node_put(np);
 	}
+	np = of_find_node_by_type(NULL, "fcu");
+	if (np == NULL) {
+		/* Some machines have strangely broken device-tree */
+		np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
+	}
+	if (np) {
+		of_platform_device_create(np, "temperature", NULL);
+		of_node_put(np);
+	}
 
 	return 0;
 }
diff --git a/drivers/macintosh/therm_pm72.c b/drivers/macintosh/therm_pm72.c
index 4454927..2e041fd 100644
--- a/drivers/macintosh/therm_pm72.c
+++ b/drivers/macintosh/therm_pm72.c
@@ -2213,6 +2213,9 @@  static void fcu_lookup_fans(struct device_node *fcu_node)
 static int fcu_of_probe(struct platform_device* dev, const struct of_device_id *match)
 {
 	state = state_detached;
+	of_dev = dev;
+
+	dev_info(&dev->dev, "PowerMac G5 Thermal control driver %s\n", VERSION);
 
 	/* Lookup the fans in the device tree */
 	fcu_lookup_fans(dev->dev.of_node);
@@ -2235,6 +2238,7 @@  static const struct of_device_id fcu_match[] =
 	},
 	{},
 };
+MODULE_DEVICE_TABLE(of, fcu_match);
 
 static struct of_platform_driver fcu_of_platform_driver = 
 {
@@ -2252,8 +2256,6 @@  static struct of_platform_driver fcu_of_platform_driver =
  */
 static int __init therm_pm72_init(void)
 {
-	struct device_node *np;
-
 	rackmac = of_machine_is_compatible("RackMac3,1");
 
 	if (!of_machine_is_compatible("PowerMac7,2") &&
@@ -2261,34 +2263,12 @@  static int __init therm_pm72_init(void)
 	    !rackmac)
 	    	return -ENODEV;
 
-	printk(KERN_INFO "PowerMac G5 Thermal control driver %s\n", VERSION);
-
-	np = of_find_node_by_type(NULL, "fcu");
-	if (np == NULL) {
-		/* Some machines have strangely broken device-tree */
-		np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
-		if (np == NULL) {
-			    printk(KERN_ERR "Can't find FCU in device-tree !\n");
-			    return -ENODEV;
-		}
-	}
-	of_dev = of_platform_device_create(np, "temperature", NULL);
-	if (of_dev == NULL) {
-		printk(KERN_ERR "Can't register FCU platform device !\n");
-		return -ENODEV;
-	}
-
-	of_register_platform_driver(&fcu_of_platform_driver);
-	
-	return 0;
+	return of_register_platform_driver(&fcu_of_platform_driver);
 }
 
 static void __exit therm_pm72_exit(void)
 {
 	of_unregister_platform_driver(&fcu_of_platform_driver);
-
-	if (of_dev)
-		of_device_unregister(of_dev);
 }
 
 module_init(therm_pm72_init);