[S] Change in coreboot[main]: superio/ite: Fix incorrect warnings

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/coreboot/+/81516?usp=email )

Change subject: superio/ite: Fix incorrect warnings
......................................................................

superio/ite: Fix incorrect warnings

Fix warning for disabled thermal inputs.

Fix warning for PECI thermal inputs if one was set up previously.
Depending on the mb, the superio will not go through power-on reset and
retain its registers. Do not trigger a warning if the current register
value aligns with the desired value. Don't return early if some input is
already configured for PECI, simply overwrite the configuration.

Both warnings were observed while porting the "HP Pro 3500 Series" mb.

Change-Id: Ibabe1b1ef55f2acb2074eceb535ec684bffc8155
Signed-off-by: Joel Linn 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81516
Tested-by: build bot (Jenkins) 
Reviewed-by: Matt DeVillier 
Reviewed-by: Nico Huber 
---
M src/superio/ite/common/env_ctrl.c
1 file changed, 9 insertions(+), 4 deletions(-)

Approvals:
  Nico Huber: Looks good to me, approved
  Matt DeVillier: Looks good to me, approved
  build bot (Jenkins): Verified

diff --git a/src/superio/ite/common/env_ctrl.c b/src/superio/ite/common/env_ctrl.c
index 9149c58..d624a92 100644
--- a/src/superio/ite/common/env_ctrl.c
+++ b/src/superio/ite/common/env_ctrl.c
@@ -67,6 +67,8 @@
    reg_extra = pnp_read_hwm5_index(base, ITE_EC_ADC_TEMP_EXTRA_CHANNEL_ENABLE);

switch (conf->mode) {
+	case THERMAL_MODE_DISABLED:
+		return;
    case THERMAL_PECI:
    	/* Some chips can set any TMPIN as the target for PECI readings
    	   while others can only read to TMPIN3. In the latter case a
@@ -78,12 +80,15 @@
    			       "PECI to TMPIN2 not supported on IT8721F\n");
    			return;
    		}
-			if (reg & ITE_EC_ADC_TEMP_EXT_REPORTS_TO_MASK) {
+			u8 reg_new = (reg & ~ITE_EC_ADC_TEMP_EXT_REPORTS_TO_MASK)
+					   | ITE_EC_ADC_TEMP_EXT_REPORTS_TO(tmpin);
+			/* Registers stick on reboot and resume,
+			   don't warn for correct reg values */
+			if (reg & ITE_EC_ADC_TEMP_EXT_REPORTS_TO_MASK && reg != reg_new) {
    			printk(BIOS_WARNING,
-				       "PECI specified for multiple TMPIN\n");
-				return;
+				       "PECI specified for another TMPIN, overwriting\n");
    		}
-			reg |= ITE_EC_ADC_TEMP_EXT_REPORTS_TO(tmpin);
+			reg = reg_new;
    	} else if (tmpin == 3) {
    		reg_extra |= ITE_EC_ADC_TEMP_EXTRA_TMPIN3_EXT;
    		pnp_write_hwm5_index(base, ITE_EC_ADC_TEMP_EXTRA_CHANNEL_ENABLE,