tests: Add acpi/acpigen-test test case

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: Icc128212c1f72beb50caca671b4bada3507d3a1f
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50520
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
diff --git a/tests/Makefile.inc b/tests/Makefile.inc
index a10e9bf..1e260fa 100644
--- a/tests/Makefile.inc
+++ b/tests/Makefile.inc
@@ -59,8 +59,8 @@
 stages+= ramstage rmodule postcar libagesa
 
 alltests:=
-subdirs:= tests/arch tests/commonlib tests/console tests/cpu tests/device
-subdirs+= tests/drivers tests/ec tests/lib tests/mainboard
+subdirs:= tests/arch tests/acpi tests/commonlib tests/console tests/cpu
+subdirs+= tests/device tests/drivers tests/ec tests/lib tests/mainboard
 subdirs+= tests/northbridge tests/security tests/soc tests/southbridge
 subdirs+= tests/superio tests/vendorcode
 
diff --git a/tests/acpi/Makefile.inc b/tests/acpi/Makefile.inc
new file mode 100644
index 0000000..b0ef5fa
--- /dev/null
+++ b/tests/acpi/Makefile.inc
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+tests-y += acpigen-test
+
+acpigen-test-srcs += tests/acpi/acpigen-test.c
+acpigen-test-srcs += src/acpi/acpigen.c
+acpigen-test-srcs += tests/stubs/console.c
diff --git a/tests/acpi/acpigen-test.c b/tests/acpi/acpigen-test.c
new file mode 100644
index 0000000..369ff29
--- /dev/null
+++ b/tests/acpi/acpigen-test.c
@@ -0,0 +1,217 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <stdlib.h>
+#include <types.h>
+#include <tests/test.h>
+#include <acpi/acpigen.h>
+
+#define ACPIGEN_TEST_BUFFER_SZ (16 * KiB)
+
+/* Returns AML package length. Works with normal and extended packages.
+   This implementation is independent from acpigen.c implementation of package length. */
+static u32 decode_package_length(const char *ptr)
+{
+	const u8 *aml = (u8 *)ptr;
+	const u32 offset = (aml[0] == EXT_OP_PREFIX ? 2 : 1);
+	u32 byte_zero_mask = 0x3F;  /* Bits [0:5] */
+	u32 byte_count = aml[offset] >> 6;
+	u32 package_length = 0;
+
+	while (byte_count) {
+		package_length |= aml[offset + byte_count] << ((byte_count << 3) - 4);
+		byte_zero_mask = 0x0F; /* Use bits [0:3] of byte 0 */
+		byte_count--;
+	}
+
+	package_length |= (aml[offset] & byte_zero_mask);
+
+	return package_length;
+}
+
+static u32 get_current_block_length(const char *base)
+{
+	const u32 offset = (base[0] == EXT_OP_PREFIX ? 2 : 1);
+
+	return ((uintptr_t)acpigen_get_current() - ((uintptr_t)base + offset));
+}
+
+static int setup_acpigen(void **state)
+{
+	void *buffer = malloc(ACPIGEN_TEST_BUFFER_SZ);
+
+	if (buffer == NULL)
+		return -1;
+
+	memset(buffer, 0, ACPIGEN_TEST_BUFFER_SZ);
+
+	*state = buffer;
+	return 0;
+}
+
+static int teardown_acpigen(void **state)
+{
+	free(*state);
+	return 0;
+}
+
+static void test_acpigen_single_if(void **state)
+{
+	char *acpigen_buf = *state;
+	u32 if_package_length = 0;
+	u32 block_length = 0;
+
+	acpigen_set_current(acpigen_buf);
+
+	/* Create dummy AML */
+	acpigen_write_if_lequal_op_int(LOCAL0_OP, 64);
+
+	for (int i = 0; i < 20; ++i)
+		acpigen_write_store_ops(ZERO_OP, LOCAL1_OP);
+
+	/* Close if */
+	acpigen_pop_len();
+
+	if_package_length = decode_package_length(acpigen_buf);
+	block_length = get_current_block_length(acpigen_buf);
+	assert_int_equal(if_package_length, block_length);
+}
+
+static void create_nested_ifs_recursive(char *stack_start[], char *stack_end[], u32 i, u32 n)
+{
+	if (i >= n)
+		return;
+
+	stack_start[i] = acpigen_get_current();
+	acpigen_write_if_and(LOCAL0_OP, ZERO_OP);
+
+	for (int k = 0; k < 3; ++k)
+		acpigen_write_store_ops(ZERO_OP, LOCAL1_OP);
+
+	create_nested_ifs_recursive(stack_start, stack_end, i + 1, n);
+
+	acpigen_pop_len();
+	stack_end[i] = acpigen_get_current();
+}
+
+static void test_acpigen_nested_ifs(void **state)
+{
+	char *acpigen_buf = *state;
+	const size_t nesting_level = 8;
+	char *block_start[8] = {0};
+	char *block_end[8] = {0};
+
+	acpigen_set_current(acpigen_buf);
+
+	create_nested_ifs_recursive(block_start, block_end, 0, nesting_level);
+
+	for (int i = 0; i < nesting_level; ++i)
+		assert_int_equal(decode_package_length(block_start[i]),
+				block_end[i] - block_start[i] - 1);
+}
+
+static void test_acpigen_write_package(void **state)
+{
+	char *acpigen_buf = *state;
+	u32 package_length;
+	u32 block_length;
+
+	acpigen_set_current(acpigen_buf);
+	acpigen_write_package(3);
+
+	acpigen_write_return_singleton_buffer(0xA);
+	acpigen_write_return_singleton_buffer(0x7);
+	acpigen_write_return_singleton_buffer(0xF);
+
+	acpigen_pop_len();
+
+	package_length = decode_package_length(acpigen_buf);
+	block_length = get_current_block_length(acpigen_buf);
+	assert_int_equal(package_length, block_length);
+}
+
+static void test_acpigen_scope_with_contents(void **state)
+{
+	char *acpigen_buf = *state;
+	char *block_start[8] = {0};
+	u32 block_counter = 0;
+	u32 package_length;
+	u32 block_length;
+
+	acpigen_set_current(acpigen_buf);
+
+	/* Scope("\_SB") { */
+	block_start[block_counter++] = acpigen_get_current();
+	acpigen_write_scope("\\_SB");
+
+	/* Device("PCI0") { */
+	block_start[block_counter++] = acpigen_get_current();
+	acpigen_write_device("PCI0");
+
+	/* Name(INT1, 0x1234) */
+	acpigen_write_name_integer("INT1", 0x1234);
+
+	/* Name (_HID, EisaId ("PNP0A08")) // PCI Express Bus */
+	acpigen_write_name("_HID");
+	acpigen_emit_eisaid("PNP0A08");
+
+	/* Method(^BN00, 0, NotSerialized) { */
+	block_start[block_counter++] = acpigen_get_current();
+	acpigen_write_method("^BN00", 0);
+
+	/* Return( 0x12 + ^PCI0.INT1 ) */
+	acpigen_write_return_op(AND_OP);
+	acpigen_write_byte(0x12);
+	acpigen_emit_namestring("^PCI0.INT1");
+
+	/* } */
+	acpigen_pop_len();
+	block_counter--;
+	package_length = decode_package_length(block_start[block_counter]);
+	block_length = get_current_block_length(block_start[block_counter]);
+	assert_int_equal(package_length, block_length);
+
+	/* Method (_BBN, 0, NotSerialized) { */
+	block_start[block_counter++] = acpigen_get_current();
+	acpigen_write_method("_BBN", 0);
+
+	/* Return (BN00 ()) */
+	acpigen_write_return_namestr("BN00");
+	acpigen_emit_byte(0x0A);
+
+	/* } */
+	acpigen_pop_len();
+	block_counter--;
+	package_length = decode_package_length(block_start[block_counter]);
+	block_length = get_current_block_length(block_start[block_counter]);
+	assert_int_equal(package_length, block_length);
+
+	/* } */
+	acpigen_pop_len();
+	block_counter--;
+	package_length = decode_package_length(block_start[block_counter]);
+	block_length = get_current_block_length(block_start[block_counter]);
+	assert_int_equal(package_length, block_length);
+
+	/* } */
+	acpigen_pop_len();
+	block_counter--;
+	package_length = decode_package_length(block_start[block_counter]);
+	block_length = get_current_block_length(block_start[block_counter]);
+	assert_int_equal(package_length, block_length);
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test_setup_teardown(test_acpigen_single_if,
+						setup_acpigen, teardown_acpigen),
+		cmocka_unit_test_setup_teardown(test_acpigen_nested_ifs,
+						setup_acpigen, teardown_acpigen),
+		cmocka_unit_test_setup_teardown(test_acpigen_write_package,
+						setup_acpigen, teardown_acpigen),
+		cmocka_unit_test_setup_teardown(test_acpigen_scope_with_contents,
+						setup_acpigen, teardown_acpigen),
+	};
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}