skylake: fix SMI GPI status handling

The current construction for processing SMI GPI events
didn't allow for the mainboard to query the state of a
particular GPI for the snapshotted SMI event. The
skylake part can route GPIs from any (there are design
limitations) GPIO group. Those status and enable registers
are within the GPIO community so one needs to gather
all the possibilities in order to query the state.

The call chain did this:
southbridge_smi_gpi(
	clear_alt_smi_status() -> reset_alt_smi_status() ->
	print_all_smi_status() -> return 0)

As a replacement the following functions and types are
introduced:

struct gpi_status - represent gpi status.
gpi_status_get() - per gpi query on struct gpi_status
gpi_clear_get_smi_status() - clear and retrieve SMI GPI status
mainboard_smi_gpi_handler() - mainboard handler using gpi_status

Also remove gpio_enable_all_smi() as that construct was never
used, but it also is quite heavy handed in that it would
enable SMI generation for all GPIs.

BUG=chrome-os-partner:43778
BRANCH=None
TEST=Built.

Original-Change-Id: Ief977e60de65d9964b8ee58f2433cae5c93872ca
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/291933
Original-Reviewed-by: Duncan Laurie <dlaurie@chromium.org>

Change-Id: Ida009393c6af88ffe910195dc79a4c0d2a4c029e
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/11208
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/src/soc/intel/skylake/smihandler.c b/src/soc/intel/skylake/smihandler.c
index 6c959555c2..fa5ef0420f 100644
--- a/src/soc/intel/skylake/smihandler.c
+++ b/src/soc/intel/skylake/smihandler.c
@@ -351,12 +351,18 @@ static void southbridge_smi_gpe0(void)
 	clear_gpe_status();
 }
 
+void __attribute__((weak))
+mainboard_smi_gpi_handler(const struct gpi_status *sts) { }
+
 static void southbridge_smi_gpi(void)
 {
-	mainboard_smi_gpi(clear_alt_smi_status());
+	struct gpi_status smi_sts;
+
+	gpi_clear_get_smi_status(&smi_sts);
+	mainboard_smi_gpi_handler(&smi_sts);
 
 	/* Clear again after mainboard handler */
-	clear_alt_smi_status();
+	gpi_clear_get_smi_status(&smi_sts);
 }
 
 static void southbridge_smi_mc(void)