mb,sb,soc/intel: Drop useless IO trap handlers

There are four requirements for the SMI to hit a printk()
this commit now removes.

Build must have DEBUG_SMI=y, otherwise any printk() is a no-op
inside SMM.
ASL must have a TRAP() with argument 0x99 or 0x32 for SMIF value.
Platform needs to have IO Trap #3 enabled at IO 0x800.
The SMI monitor must call io_trap_handler for IO Trap #3.

At the moment, only getac/p470 would meet the above criteria
with TRAP(0x32) in its DSDT _INI method. The ASL ignores any
return value of TRAP() calls made.

A mainboard IO trap handler should have precedence over
a southbridge IO trap handler. At the moment we seem to have
no cases of the latter to support, so remove the latter.

Change-Id: I3a3298c8d9814db8464fbf7444c6e0e6ac6ac008
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70365
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

src/southbridge/intel/bd82x6x/smihandler.c

@@ -19,23 +19,6 @@
 
 #include "pch.h"
 
-int southbridge_io_trap_handler(int smif)
-{
-	switch (smif) {
-	case 0x32:
-		printk(BIOS_DEBUG, "OS Init\n");
-		/* gnvs->smif:
-		 *  On success, the IO Trap Handler returns 0
-		 *  On failure, the IO Trap Handler returns a value != 0
-		 */
-		gnvs->smif = 0;
-		return 1; /* IO trap handled */
-	}
-
-	/* Not handled */
-	return 0;
-}
-
 static void southbridge_gate_memory_reset_real(int offset,
 					       u16 use, u16 io, u16 lvl)
 {

src/southbridge/intel/i82801gx/smihandler.c

@@ -19,23 +19,6 @@
 /* While we read PMBASE dynamically in case it changed, let's initialize it with a sane value */
 u16 pmbase = DEFAULT_PMBASE;
 
-int southbridge_io_trap_handler(int smif)
-{
-	switch (smif) {
-	case 0x32:
-		printk(BIOS_DEBUG, "OS Init\n");
-		/* gnvs->smif:
-		 *  On success, the IO Trap Handler returns 0
-		 *  On failure, the IO Trap Handler returns a value != 0
-		 */
-		gnvs->smif = 0;
-		return 1; /* IO trap handled */
-	}
-
-	/* Not handled */
-	return 0;
-}
-
 void southbridge_smi_monitor(void)
 {
 #define IOTRAP(x) (trap_sts & (1 << x))

src/southbridge/intel/i82801ix/smihandler.c

@@ -9,23 +9,6 @@
 
 #include <soc/nvs.h>
 
-int southbridge_io_trap_handler(int smif)
-{
-	switch (smif) {
-	case 0x32:
-		printk(BIOS_DEBUG, "OS Init\n");
-		/* gnvs->smif:
-		 *  On success, the IO Trap Handler returns 0
-		 *  On failure, the IO Trap Handler returns a value != 0
-		 */
-		gnvs->smif = 0;
-		return 1; /* IO trap handled */
-	}
-
-	/* Not handled */
-	return 0;
-}
-
 void southbridge_smi_monitor(void)
 {
 #define IOTRAP(x) (trap_sts & (1 << x))

src/southbridge/intel/lynxpoint/smihandler.c

@@ -19,23 +19,6 @@
 #include "me.h"
 #include "pch.h"
 
-int southbridge_io_trap_handler(int smif)
-{
-	switch (smif) {
-	case 0x32:
-		printk(BIOS_DEBUG, "OS Init\n");
-		/* gnvs->smif:
-		 *  On success, the IO Trap Handler returns 0
-		 *  On failure, the IO Trap Handler returns a value != 0
-		 */
-		gnvs->smif = 0;
-		return 1; /* IO trap handled */
-	}
-
-	/* Not handled */
-	return 0;
-}
-
 /**
  * @brief Set the EOS bit
  */