ich9: implement strap SPKR pin logic

If the signal is sampled high, this indicates that the system is
strapped to the "No Reboot" mode (ICH9 will disable the TCO Timer system
reboot feature). The status of this strap is readable via the NO_REBOOT
bit (CC: offset 0x3410:bit 5).

The NO_REBOOT bit is set when SPKR pin on ICH9 is sampled high. This bit
may be set or cleared by software if the strap is sampled low but may
not override the strap when it indicates "No Reboot".

This patch implements the logic where hardware has ability to set SPKR
pin through a property named "noreboot" and it's sampled high by
default.

Signed-off-by: Paulo Alcantara <pcacjr@zytor.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

4 files changed, 28 insertions, 3 deletions

diff --git a/hw/acpi/tco.c b/hw/acpi/tco.c
index 1794a54545..7a026c255b 100644
--- a/hw/acpi/tco.c
+++ b/hw/acpi/tco.c
@@ -64,7 +64,7 @@ static void tco_timer_expired(void *opaque)
         tr->tco.sts2 |= TCO_BOOT_STS;
         tr->timeouts_no = 0;
 
-        if (!(gcs & ICH9_CC_GCS_NO_REBOOT)) {
+        if (!lpc->pin_strap.spkr_hi && !(gcs & ICH9_CC_GCS_NO_REBOOT)) {
             watchdog_perform_action();
             tco_timer_stop(tr);
             return;
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index 7af24fa8eb..360699f6fd 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -692,6 +692,11 @@ static const VMStateDescription vmstate_ich9_lpc = {
     }
 };
 
+static Property ich9_lpc_properties[] = {
+    DEFINE_PROP_BOOL("noreboot", ICH9LPCState, pin_strap.spkr_hi, true),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void ich9_lpc_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -703,6 +708,7 @@ static void ich9_lpc_class_init(ObjectClass *klass, void *data)
     dc->reset = ich9_lpc_reset;
     k->init = ich9_lpc_init;
     dc->vmsd = &vmstate_ich9_lpc;
+    dc->props = ich9_lpc_properties;
     k->config_write = ich9_lpc_config_write;
     dc->desc = "ICH9 LPC bridge";
     k->vendor_id = PCI_VENDOR_ID_INTEL;
diff --git a/include/hw/i386/ich9.h b/include/hw/i386/ich9.h
index ecb3b1038c..b9d2b04b6e 100644
--- a/include/hw/i386/ich9.h
+++ b/include/hw/i386/ich9.h
@@ -46,6 +46,11 @@ typedef struct ICH9LPCState {
     ICH9LPCPMRegs pm;
     uint32_t sci_level; /* track sci level */
 
+    /* 2.24 Pin Straps */
+    struct {
+        bool spkr_hi;
+    } pin_strap;
+
     /* 10.1 Chipset Configuration registers(Memory Space)
      which is pointed by RCBA */
     uint8_t chip_config[ICH9_CC_SIZE];
diff --git a/tests/tco-test.c b/tests/tco-test.c
index 1a2fe3de28..6a48188b9d 100644
--- a/tests/tco-test.c
+++ b/tests/tco-test.c
@@ -42,6 +42,7 @@ enum {
 
 typedef struct {
     const char *args;
+    bool noreboot;
     QPCIDevice *dev;
     void *lpc_base;
     void *tco_io_base;
@@ -53,7 +54,9 @@ static void test_init(TestData *d)
     QTestState *qs;
     char *s;
 
-    s = g_strdup_printf("-machine q35 %s", !d->args ? "" : d->args);
+    s = g_strdup_printf("-machine q35 %s %s",
+                        d->noreboot ? "" : "-global ICH9-LPC.noreboot=false",
+                        !d->args ? "" : d->args);
     qs = qtest_start(s);
     qtest_irq_intercept_in(qs, "ioapic");
     g_free(s);
@@ -135,6 +138,7 @@ static void test_tco_defaults(void)
     TestData d;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
     g_assert_cmpint(qpci_io_readw(d.dev, d.tco_io_base + TCO_RLD), ==,
                     TCO_RLD_DEFAULT);
@@ -167,6 +171,7 @@ static void test_tco_timeout(void)
     int ret;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     stop_tco(&d);
@@ -210,6 +215,7 @@ static void test_tco_max_timeout(void)
     int ret;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     stop_tco(&d);
@@ -253,6 +259,7 @@ static void test_tco_second_timeout_pause(void)
     QDict *ad;
 
     td.args = "-watchdog-action pause";
+    td.noreboot = false;
     test_init(&td);
 
     stop_tco(&td);
@@ -277,6 +284,7 @@ static void test_tco_second_timeout_reset(void)
     QDict *ad;
 
     td.args = "-watchdog-action reset";
+    td.noreboot = false;
     test_init(&td);
 
     stop_tco(&td);
@@ -301,6 +309,7 @@ static void test_tco_second_timeout_shutdown(void)
     QDict *ad;
 
     td.args = "-watchdog-action shutdown";
+    td.noreboot = false;
     test_init(&td);
 
     stop_tco(&td);
@@ -325,6 +334,7 @@ static void test_tco_second_timeout_none(void)
     QDict *ad;
 
     td.args = "-watchdog-action none";
+    td.noreboot = false;
     test_init(&td);
 
     stop_tco(&td);
@@ -349,6 +359,7 @@ static void test_tco_ticks_counter(void)
     uint16_t rld;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     stop_tco(&d);
@@ -375,6 +386,7 @@ static void test_tco1_control_bits(void)
     uint16_t val;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     val = TCO_LOCK;
@@ -394,6 +406,7 @@ static void test_tco1_status_bits(void)
     int ret;
 
     d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     stop_tco(&d);
@@ -421,7 +434,8 @@ static void test_tco2_status_bits(void)
     uint16_t val;
     int ret;
 
-    d.args = "-watchdog-action none";
+    d.args = NULL;
+    d.noreboot = true;
     test_init(&d);
 
     stop_tco(&d);