skylake: add global reset cause registers to power state

Log the global reset causes in the power state structure.
While working in there pack the struct and use width-specific
types as this struct crosses the romstate <-> ramstage boundary.
Lastly, remove hsio version as it wasn't being written or read.

After global reset induced:
PM1_STS:   0000
PM1_EN:    0000
PM1_CNT:   00000000
TCO_STS:   0000 0000
GPE0_STS:  00000000 00000000 00000000 00000000
GPE0_EN:   00000000 00000000 00000000 00000000
GEN_PMCON: d8010200 00003808
GBLRST_CAUSE: 00000000 00040004
Previous Sleep State: S0

BUG=None
BRANCH=None
TEST=Induced global reset on glados using ETR3 register and write
     to cf9.

Change-Id: I97b93de336e74c0e02199241376e74340612f0a7
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: bbc8f1d62131c0381e9d401f3281ee7a17fc2a47
Original-Change-Id: I1a8e5d07c6c0e09c163effe27491d8f198823617
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/286640
Original-Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/11011
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
diff --git a/src/soc/intel/skylake/include/soc/pm.h b/src/soc/intel/skylake/include/soc/pm.h
index 2e722bf..6b75641 100644
--- a/src/soc/intel/skylake/include/soc/pm.h
+++ b/src/soc/intel/skylake/include/soc/pm.h
@@ -129,10 +129,9 @@
 	uint32_t gpe0_en[4];
 	uint32_t gen_pmcon_a;
 	uint32_t gen_pmcon_b;
-	int prev_sleep_state;
-	uint16_t hsio_version;
-	uint16_t hsio_checksum;
-};
+	uint32_t gblrst_cause[0];
+	uint32_t prev_sleep_state;
+} __attribute__ ((packed));
 
 /* PM1_CNT */
 void enable_pm1_control(uint32_t mask);
diff --git a/src/soc/intel/skylake/include/soc/pmc.h b/src/soc/intel/skylake/include/soc/pmc.h
index 72c9a59..699e795 100644
--- a/src/soc/intel/skylake/include/soc/pmc.h
+++ b/src/soc/intel/skylake/include/soc/pmc.h
@@ -57,6 +57,8 @@
 #define  S5AC_GATE_SUS		(1 << 14)
 #define PMSYNC_TPR_CFG		0xc4
 #define  PMSYNC_LOCK		(1 << 31)
+#define GBLRST_CAUSE0		0x124
+#define GBLRST_CAUSE1		0x128
 
 
 /* TCO registers and fields live behind TCOBASE I/O bar in SMBus device. */
diff --git a/src/soc/intel/skylake/romstage/power_state.c b/src/soc/intel/skylake/romstage/power_state.c
index 5c94e89..68a11a4 100644
--- a/src/soc/intel/skylake/romstage/power_state.c
+++ b/src/soc/intel/skylake/romstage/power_state.c
@@ -54,10 +54,10 @@
 ROMSTAGE_CBMEM_INIT_HOOK(migrate_power_state)
 
 /* Return 0, 3, or 5 to indicate the previous sleep state. */
-static int prev_sleep_state(struct chipset_power_state *ps)
+static uint32_t prev_sleep_state(struct chipset_power_state *ps)
 {
 	/* Default to S0. */
-	int prev_sleep_state = SLEEP_STATE_S0;
+	uint32_t prev_sleep_state = SLEEP_STATE_S0;
 
 	if (ps->pm1_sts & WAK_STS) {
 		switch ((ps->pm1_cnt & SLP_TYP) >> SLP_TYP_SHIFT) {
@@ -112,6 +112,9 @@
 	printk(BIOS_DEBUG, "GEN_PMCON: %08x %08x\n",
 	       ps->gen_pmcon_a, ps->gen_pmcon_b);
 
+	printk(BIOS_DEBUG, "GBLRST_CAUSE: %08x %08x\n",
+	       ps->gblrst_cause[0], ps->gblrst_cause[1]);
+
 	printk(BIOS_DEBUG, "Previous Sleep State: S%d\n",
 	       ps->prev_sleep_state);
 }
@@ -120,6 +123,7 @@
 struct chipset_power_state *fill_power_state(void)
 {
 	uint16_t tcobase;
+	uint8_t *pmc;
 	struct chipset_power_state *ps = car_get_var_ptr(&power_state);
 
 	tcobase = pmc_tco_regs();
@@ -141,6 +145,10 @@
 	ps->gen_pmcon_a = pci_read_config32(PCH_DEV_PMC, GEN_PMCON_A);
 	ps->gen_pmcon_b = pci_read_config32(PCH_DEV_PMC, GEN_PMCON_B);
 
+	pmc = pmc_mmio_regs();
+	ps->gblrst_cause[0] = read32(pmc + GBLRST_CAUSE0);
+	ps->gblrst_cause[1] = read32(pmc + GBLRST_CAUSE1);
+
 	ps->prev_sleep_state = prev_sleep_state(ps);
 
 	dump_power_state(ps);