drm/nouveau/pm: introduce generic handler for on-chip fan controller

The handling of the internal pwm fan controller is similar enough between
current chipsets that it makes sense to share the logic, and bugfixes :)

No hw backends converted yet, will automatically fall-through to the
"old" per-chipset fanspeed hooks for now.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 78 insertions, 16 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_pm.c b/drivers/gpu/drm/nouveau/nouveau_pm.c
index 23b297fd6f61..b94364dbe352 100644
--- a/drivers/gpu/drm/nouveau/nouveau_pm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_pm.c
@@ -35,6 +35,74 @@
 #include <linux/hwmon-sysfs.h>
 
 static int
+nouveau_pwmfan_get(struct drm_device *dev)
+{
+        struct drm_nouveau_private *dev_priv = dev->dev_private;
+        struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
+        struct nouveau_pm_engine *pm = &dev_priv->engine.pm;
+        struct dcb_gpio_entry *gpio;
+        u32 divs, duty;
+        int ret;
+
+        if (!pm->pwm_get) {
+                if (pm->fanspeed_get)
+                        return pm->fanspeed_get(dev);
+                return -ENODEV;
+        }
+
+        gpio = nouveau_bios_gpio_entry(dev, DCB_GPIO_PWM_FAN);
+        if (gpio) {
+                ret = pm->pwm_get(dev, gpio, &divs, &duty);
+                if (ret == 0) {
+                        divs = max(divs, duty);
+                        if (dev_priv->card_type <= NV_40 ||
+                            (gpio->state[0] & 1))
+                                duty = divs - duty;
+                        return (duty * 100) / divs;
+                }
+
+                return pgpio->get(dev, gpio->tag) * 100;
+        }
+
+        return -ENODEV;
+}
+
+static int
+nouveau_pwmfan_set(struct drm_device *dev, int percent)
+{
+        struct drm_nouveau_private *dev_priv = dev->dev_private;
+        struct nouveau_pm_engine *pm = &dev_priv->engine.pm;
+        struct dcb_gpio_entry *gpio;
+        u32 divs, duty;
+
+        if (!pm->pwm_set) {
+                if (pm->fanspeed_set)
+                        return pm->fanspeed_set(dev, percent);
+                return -ENODEV;
+        }
+
+        gpio = nouveau_bios_gpio_entry(dev, DCB_GPIO_PWM_FAN);
+        if (gpio) {
+                divs = pm->pwm_divisor;
+                if (pm->fan.pwm_freq) {
+                        /*XXX: PNVIO clock more than likely... */
+                        divs = 135000 / pm->fan.pwm_freq;
+                        if (dev_priv->chipset < 0xa3)
+                                divs /= 4;
+                }
+
+                duty = ((divs * percent) + 99) / 100;
+                if (dev_priv->card_type <= NV_40 ||
+                    (gpio->state[0] & 1))
+                        duty = divs - duty;
+
+                return pm->pwm_set(dev, gpio, divs, duty);
+        }
+
+        return -ENODEV;
+}
+
+static int
 nouveau_pm_clock_set(struct drm_device *dev, struct nouveau_pm_level *perflvl,
                      u8 id, u32 khz)
 {
@@ -68,9 +136,9 @@ nouveau_pm_perflvl_set(struct drm_device *dev, struct nouveau_pm_level *perflvl)
          *     on recent boards..  or maybe on some other factor we don't
          *     know about?
          */
-        if (pm->fanspeed_set && perflvl->fanspeed) {
-                ret = pm->fanspeed_set(dev, perflvl->fanspeed);
-                if (ret)
+        if (perflvl->fanspeed) {
+                ret = nouveau_pwmfan_set(dev, perflvl->fanspeed);
+                if (ret && ret != -ENODEV)
                         NV_ERROR(dev, "set fanspeed failed: %d\n", ret);
         }
 
@@ -171,11 +239,9 @@ nouveau_pm_perflvl_get(struct drm_device *dev, struct nouveau_pm_level *perflvl)
                 }
         }
 
-        if (pm->fanspeed_get) {
-                ret = pm->fanspeed_get(dev);
-                if (ret > 0)
-                        perflvl->fanspeed = ret;
-        }
+        ret = nouveau_pwmfan_get(dev);
+        if (ret > 0)
+                perflvl->fanspeed = ret;
 
         return 0;
 }
@@ -471,12 +537,9 @@ static ssize_t
 nouveau_hwmon_get_pwm0(struct device *d, struct device_attribute *a, char *buf)
 {
         struct drm_device *dev = dev_get_drvdata(d);
-        struct drm_nouveau_private *dev_priv = dev->dev_private;
-        struct nouveau_pm_engine *pm = &dev_priv->engine.pm;
-        int ret = -ENODEV;
+        int ret;
 
-        if (pm->fanspeed_get)
-                ret = pm->fanspeed_get(dev);
+        ret = nouveau_pwmfan_get(dev);
         if (ret < 0)
                 return ret;
 
@@ -504,8 +567,7 @@ nouveau_hwmon_set_pwm0(struct device *d, struct device_attribute *a,
         if (value > pm->fan.max_duty)
                 value = pm->fan.max_duty;
 
-        if (pm->fanspeed_set)
-                ret = pm->fanspeed_set(dev, value);
+        ret = nouveau_pwmfan_set(dev, value);
         if (ret)
                 return ret;
 
@@ -660,7 +722,7 @@ nouveau_hwmon_init(struct drm_device *dev)
         /*XXX: incorrect, need better detection for this, some boards have
          *     the gpio entries for pwm fan control even when there's no
          *     actual fan connected to it... therm table? */
-        if (pm->fanspeed_get && pm->fanspeed_get(dev) >= 0) {
+        if (nouveau_pwmfan_get(dev) >= 0) {
                 ret = sysfs_create_group(&dev->pdev->dev.kobj,
                                          &hwmon_pwm_fan_attrgroup);
                 if (ret)