diff options
Diffstat (limited to 'drivers/thermal/ti-soc-thermal/ti-bandgap.c')
| -rw-r--r-- | drivers/thermal/ti-soc-thermal/ti-bandgap.c | 78 |
1 files changed, 76 insertions, 2 deletions
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c index 62a5d449c388..bc14dc874594 100644 --- a/drivers/thermal/ti-soc-thermal/ti-bandgap.c +++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c @@ -119,6 +119,37 @@ exit: } /** + * 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 * @id: bandgap sensor id @@ -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; |