Merge remote-tracking branch 'asoc/topic/rcar' into asoc-next

[sfrench/cifs-2.6.git] / drivers / thermal / ti-soc-thermal / ti-bandgap.c

diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
index 62a5d449c38805019db7d554e6c0f7f43d215341..bc14dc874594e4d9fd37a68874bb6adb6eb4b562 100644 (file)
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.c
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
@@ -118,6 +118,37 @@ exit:
        return ret;
 }
 
+/**
+ * ti_errata814_bandgap_read_temp() - helper function to read dra7 sensor temperature
+ * @bgp: pointer to ti_bandgap structure
+ * @reg: desired register (offset) to be read
+ *
+ * Function to read dra7 bandgap sensor temperature. This is done separately
+ * so as to workaround the errata "Bandgap Temperature read Dtemp can be
+ * corrupted" - Errata ID: i814".
+ * Read accesses to registers listed below can be corrupted due to incorrect
+ * resynchronization between clock domains.
+ * Read access to registers below can be corrupted :
+ * CTRL_CORE_DTEMP_MPU/GPU/CORE/DSPEVE/IVA_n (n = 0 to 4)
+ * CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA_n
+ *
+ * Return: the register value.
+ */
+static u32 ti_errata814_bandgap_read_temp(struct ti_bandgap *bgp,  u32 reg)
+{
+       u32 val1, val2;
+
+       val1 = ti_bandgap_readl(bgp, reg);
+       val2 = ti_bandgap_readl(bgp, reg);
+
+       /* If both times we read the same value then that is right */
+       if (val1 == val2)
+               return val1;
+
+       /* if val1 and val2 are different read it third time */
+       return ti_bandgap_readl(bgp, reg);
+}
+
 /**
  * ti_bandgap_read_temp() - helper function to read sensor temperature
  * @bgp: pointer to ti_bandgap structure
@@ -148,7 +179,11 @@ static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
        }
 
        /* read temperature */
-       temp = ti_bandgap_readl(bgp, reg);
+       if (TI_BANDGAP_HAS(bgp, ERRATA_814))
+               temp = ti_errata814_bandgap_read_temp(bgp, reg);
+       else
+               temp = ti_bandgap_readl(bgp, reg);
+
        temp &= tsr->bgap_dtemp_mask;
 
        if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
@@ -410,7 +445,7 @@ static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id,
 {
        struct temp_sensor_data *ts_data = bgp->conf->sensors[id].ts_data;
        struct temp_sensor_registers *tsr;
-       u32 thresh_val, reg_val, t_hot, t_cold;
+       u32 thresh_val, reg_val, t_hot, t_cold, ctrl;
        int err = 0;
 
        tsr = bgp->conf->sensors[id].registers;
@@ -442,8 +477,47 @@ static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id,
                  ~(tsr->threshold_thot_mask | tsr->threshold_tcold_mask);
        reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)) |
                   (t_cold << __ffs(tsr->threshold_tcold_mask));
+
+       /**
+        * Errata i813:
+        * Spurious Thermal Alert: Talert can happen randomly while the device
+        * remains under the temperature limit defined for this event to trig.
+        * This spurious event is caused by a incorrect re-synchronization
+        * between clock domains. The comparison between configured threshold
+        * and current temperature value can happen while the value is
+        * transitioning (metastable), thus causing inappropriate event
+        * generation. No spurious event occurs as long as the threshold value
+        * stays unchanged. Spurious event can be generated while a thermal
+        * alert threshold is modified in
+        * CONTROL_BANDGAP_THRESHOLD_MPU/GPU/CORE/DSPEVE/IVA_n.
+        */
+
+       if (TI_BANDGAP_HAS(bgp, ERRATA_813)) {
+               /* Mask t_hot and t_cold events at the IP Level */
+               ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
+
+               if (hot)
+                       ctrl &= ~tsr->mask_hot_mask;
+               else
+                       ctrl &= ~tsr->mask_cold_mask;
+
+               ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
+       }
+
+       /* Write the threshold value */
        ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold);
 
+       if (TI_BANDGAP_HAS(bgp, ERRATA_813)) {
+               /* Unmask t_hot and t_cold events at the IP Level */
+               ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
+               if (hot)
+                       ctrl |= tsr->mask_hot_mask;
+               else
+                       ctrl |= tsr->mask_cold_mask;
+
+               ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
+       }
+
        if (err) {
                dev_err(bgp->dev, "failed to reprogram thot threshold\n");
                err = -EIO;