test: fit: cover mkimage load address overlap detection

Add a test that mkimage rejects a FIT image whose configuration
references a kernel and an FDT with the same load address, and that
the error message names the offending configuration and images.

Also add a companion test for the intended escape hatch: two images
may use the same load address as long as no single configuration
references both of them. Only one configuration is selected at
runtime, so such images never coexist in memory. This mirrors the TI
K3 tispl layout after commit c85bf61b14f9 ("arm: k3: select tifsstub
via board_fit_config_name_match"), where each security state has its
own configuration and all tifsstub variants share one load address.

Signed-off-by: Aristo Chen <aristo.chen@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 136 insertions, 0 deletions

diff --git a/test/py/tests/test_fit_mkimage_validate.py b/test/py/tests/test_fit_mkimage_validate.py
index 5922f071dd8..7c9213b2796 100644
--- a/test/py/tests/test_fit_mkimage_validate.py
+++ b/test/py/tests/test_fit_mkimage_validate.py
@@ -160,3 +160,139 @@ def test_fit_auto_basename_dotted_directory(ubman, dtb_relpath, expected_desc):
     assert desc == expected_desc, (
         f"Expected /images/fdt-1 description {expected_desc!r}, got {desc!r}"
     )
+
+@pytest.mark.boardspec('sandbox')
+@pytest.mark.requiredtool('dtc')
+def test_fit_load_addr_overlap(ubman):
+    """Test that mkimage fails when images in one config overlap in memory"""
+
+    its_fname = fit_util.make_fname(ubman, "overlap.its")
+    itb_fname = fit_util.make_fname(ubman, "overlap.itb")
+    kernel = fit_util.make_kernel(ubman, 'kernel.bin', 'kernel')
+    fdt = fit_util.make_dtb(ubman, '''
+/dts-v1/;
+/ {
+    model = "Test FDT";
+    compatible = "test";
+};
+''', 'test')
+
+    # Write ITS with kernel and FDT sharing the same load address
+    its_text = '''
+/dts-v1/;
+
+/ {
+    images {
+        kernel@1 {
+            description = "Test Kernel";
+            data = /incbin/("kernel.bin");
+            type = "kernel";
+            arch = "sandbox";
+            os = "linux";
+            compression = "none";
+            load = <0x40000>;
+            entry = <0x40000>;
+        };
+        fdt@1 {
+            description = "Test FDT";
+            data = /incbin/("test.dtb");
+            type = "flat_dt";
+            arch = "sandbox";
+            os = "linux";
+            compression = "none";
+            load = <0x40000>;
+            entry = <0x40000>;
+        };
+    };
+
+    configurations {
+        default = "conf@1";
+        conf@1 {
+            kernel = "kernel@1";
+            fdt = "fdt@1";
+        };
+    };
+};
+'''
+
+    with open(its_fname, 'w') as f:
+        f.write(its_text)
+
+    mkimage = os.path.join(ubman.config.build_dir, 'tools/mkimage')
+    cmd = [mkimage, '-f', its_fname, itb_fname]
+
+    result = subprocess.run(cmd, capture_output=True, text=True)
+
+    assert result.returncode != 0, "mkimage should fail due to memory overlap"
+    assert "has overlapping load regions" in result.stderr
+    # Check that it identifies the configuration and the specific
+    # overlapping components
+    assert "conf@1" in result.stderr
+    assert "kernel@1" in result.stderr and "fdt@1" in result.stderr
+
+@pytest.mark.boardspec('sandbox')
+@pytest.mark.requiredtool('dtc')
+def test_fit_same_load_addr_different_configs(ubman):
+    """Test that images may share a load address across configurations
+
+    Only one configuration is selected at runtime, so images that are
+    referenced by different configurations never coexist in memory. This
+    mirrors the TI K3 tispl layout, where each security state has its own
+    configuration and all tifsstub variants use the same load address.
+    """
+
+    its_fname = fit_util.make_fname(ubman, "exclusive.its")
+    itb_fname = fit_util.make_fname(ubman, "exclusive.itb")
+    kernel = fit_util.make_kernel(ubman, 'kernel.bin', 'kernel')
+
+    its_text = '''
+/dts-v1/;
+
+/ {
+    images {
+        kernel@1 {
+            description = "Test Kernel HS";
+            data = /incbin/("kernel.bin");
+            type = "kernel";
+            arch = "sandbox";
+            os = "linux";
+            compression = "none";
+            load = <0x40000>;
+            entry = <0x40000>;
+        };
+        kernel@2 {
+            description = "Test Kernel GP";
+            data = /incbin/("kernel.bin");
+            type = "kernel";
+            arch = "sandbox";
+            os = "linux";
+            compression = "none";
+            load = <0x40000>;
+            entry = <0x40000>;
+        };
+    };
+
+    configurations {
+        default = "conf@1";
+        conf@1 {
+            kernel = "kernel@1";
+        };
+        conf@2 {
+            kernel = "kernel@2";
+        };
+    };
+};
+'''
+
+    with open(its_fname, 'w') as f:
+        f.write(its_text)
+
+    mkimage = os.path.join(ubman.config.build_dir, 'tools/mkimage')
+    cmd = [mkimage, '-f', its_fname, itb_fname]
+
+    result = subprocess.run(cmd, capture_output=True, text=True)
+
+    assert result.returncode == 0, (
+        f"mkimage should accept same load address in different configs:\n"
+        f"stderr:\n{result.stderr}"
+    )