x86: sandbox: Add a PMC emulator and test

Add a simple PMC for sandbox to permit tests to run.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/test/dm/Makefile b/test/dm/Makefile
index 0c2fd5c..10a19a0 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -36,6 +36,7 @@
 obj-$(CONFIG_PCH) += pch.o
 obj-$(CONFIG_PHY) += phy.o
 obj-$(CONFIG_POWER_DOMAIN) += power-domain.o
+obj-$(CONFIG_ACPI_PMC) += pmc.o
 obj-$(CONFIG_DM_PWM) += pwm.o
 obj-$(CONFIG_RAM) += ram.o
 obj-y += regmap.o
diff --git a/test/dm/pmc.c b/test/dm/pmc.c
new file mode 100644
index 0000000..1a22283
--- /dev/null
+++ b/test/dm/pmc.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for power-management controller uclass (PMC)
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <power/acpi_pmc.h>
+#include <dm/test.h>
+#include <test/ut.h>
+
+/* Base test of the PMC uclass */
+static int dm_test_pmc_base(struct unit_test_state *uts)
+{
+	struct acpi_pmc_upriv *upriv;
+	struct udevice *dev;
+
+	ut_assertok(uclass_first_device_err(UCLASS_ACPI_PMC, &dev));
+
+	ut_assertok(pmc_disable_tco(dev));
+	ut_assertok(pmc_init(dev));
+	ut_assertok(pmc_prev_sleep_state(dev));
+
+	/* Check some values to see that I/O works */
+	upriv = dev_get_uclass_priv(dev);
+	ut_asserteq(0x24, upriv->gpe0_sts[1]);
+	ut_asserteq(0x64, upriv->tco1_sts);
+
+	return 0;
+}
+DM_TEST(dm_test_pmc_base, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);