Check if ASSR is correctly disabled or enabled on DP/eDP links.

Signed-off-by: Stylon Wang <redacted>
---
 tests/amdgpu/amd_assr.c  | 266 +++++++++++++++++++++++++++++++++++++++
 tests/amdgpu/meson.build |   1 +
 2 files changed, 267 insertions(+)
 create mode 100644 tests/amdgpu/amd_assr.c

diff --git a/tests/amdgpu/amd_assr.c b/tests/amdgpu/amd_assr.c
new file mode 100644
index 00000000..bcddbaad
--- /dev/null
+++ b/tests/amdgpu/amd_assr.c

@@ -0,0 +1,266 @@
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "igt.h"
+#include "igt_sysfs.h"
+#include <dirent.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+IGT_TEST_DESCRIPTION("Check if ASSR is enabled on eDP links that support"
+                    "the display authentication by changing scrambling sequence."
+                    "The test also covers embedded and non-removable "
+                    "displays that appears as DP.");
+
+/* Common test data. */
+typedef struct data {
+       igt_display_t display;
+       igt_plane_t *primary;
+       int fd;
+} data_t;
+
+/* Common test setup. */
+static void test_init(data_t *data)
+{
+       igt_display_reset(&data->display);
+}
+
+/* Common test cleanup. */
+static void test_fini(data_t *data)
+{
+       igt_display_reset(&data->display);
+}
+
+static char *find_aux_dev(data_t *data, igt_output_t *output)
+{
+       char sysfs_name[PATH_MAX] = { 0 };
+       /* +7 only to get rid of snprintf_chk warning.
+        * Path name cannot exceed the size of PATH_MAX anyway.
+        */
+       char conn_dir_name[PATH_MAX+7] = { 0 };
+       static char aux_name[PATH_MAX] = { 0 };
+       DIR *dir;
+       struct dirent *dirent;
+
+       if(igt_sysfs_path(data->fd, sysfs_name, sizeof(sysfs_name))) {
+                       snprintf(conn_dir_name, sizeof(conn_dir_name),
+                                       "%s%scard0%s%s",
+                                       sysfs_name, "/", "-", output->name);
+       }
+
+       dir = opendir(conn_dir_name);
+       if (!dir)
+               return NULL;
+
+       while((dirent = readdir(dir))) {
+               if (strncmp(dirent->d_name, "drm_dp_aux", sizeof("drm_dp_aux")-1))
+                       continue;
+
+               strncpy(aux_name, dirent->d_name, sizeof(aux_name));
+               break;
+       }
+
+       closedir(dir);
+
+       if (aux_name[0])
+               return aux_name;
+       else
+               return NULL;
+}
+
+static void parse_dpcd(const char *aux_dev, bool *assr_supported, bool *assr_enabled)
+{
+       char aux_name[256];
+       char dpcd[2];
+       int aux_fd;
+
+       snprintf(aux_name, sizeof(aux_name), "/dev/%s", aux_dev);
+
+       igt_assert((aux_fd = open(aux_name, O_RDONLY)) >= 0);
+
+       /* Refer to section 3.5 of VESA eDP standard v1.4b:
+        * Display Authentication and Content Protection Support
+        */
+
+       /* DPCD register 0x0D, eDP_CONFIGURATION_CAP
+        * Bit 0 is ALTERNATE_SCRAMBLER_RESET_CAPABLE,
+        * indicating if eDP device can use ASSR.
+        */
+       igt_assert(lseek(aux_fd, 0x0D, SEEK_SET));
+       igt_assert(read(aux_fd, &dpcd[0], 1) == 1);
+       *assr_supported = dpcd[0] & 0x01;
+
+       /* DPCD register 0x10A, eDP_CONFIGURATION_SET
+        * Bit 0 is ALTERNATE_SCRAMBLER_RESET_ENABLE,
+        * indicating if ASSR is enabled on the eDP device
+        */
+       igt_assert(lseek(aux_fd, 0x10A, SEEK_SET));
+       igt_assert(read(aux_fd, &dpcd[1], 1) == 1);
+       *assr_enabled = dpcd[1] & 0x01;
+
+       close(aux_fd);
+}
+
+static bool get_internal_display_flag(data_t *data, igt_output_t *output)
+{
+       char buf[256];
+       char *start_loc;
+       int fd, res;
+       int internal_flag;
+
+       fd = igt_debugfs_connector_dir(data->fd, output->name, O_RDONLY);
+       if (fd < 0)
+               return false;
+
+       res = igt_debugfs_simple_read(fd, "internal_display", buf, sizeof(buf));
+       if (res <= 0) {
+               close(fd);
+               return false;
+       }
+
+       close(fd);
+
+       igt_assert(start_loc = strstr(buf, "Internal: "));
+       igt_assert_eq(sscanf(start_loc, "Internal: %u", &internal_flag), 1);
+
+       return (bool)internal_flag;
+}
+
+static void present_visual_pattern(data_t *data, igt_output_t *output)
+{
+       igt_plane_t *primary;
+       igt_pipe_t *pipe;
+       drmModeModeInfo *mode;
+       igt_fb_t fb;
+       cairo_t *cr;
+
+       mode = igt_output_get_mode(output);
+       igt_assert(mode);
+
+       pipe = &data->display.pipes[PIPE_A];
+       primary =
+               igt_pipe_get_plane_type(pipe, DRM_PLANE_TYPE_PRIMARY);
+       igt_output_set_pipe(output, PIPE_A);
+
+       igt_create_fb(data->fd, mode->hdisplay, mode->vdisplay, DRM_FORMAT_XRGB8888, 0, &fb);
+       cr = igt_get_cairo_ctx(fb.fd, &fb);
+       igt_paint_test_pattern(cr, fb.width, fb.height);
+
+       igt_put_cairo_ctx(cr);
+
+       igt_plane_set_fb(primary, &fb);
+       igt_display_commit2(&data->display, COMMIT_ATOMIC);
+
+       /* useful for visual inspection on artifacts */
+       igt_debug_wait_for_keypress("assr");
+
+       igt_plane_set_fb(primary, NULL);
+       igt_remove_fb(data->fd, &fb);
+       igt_output_set_pipe(output, PIPE_NONE);
+       igt_display_commit2(&data->display, COMMIT_ATOMIC);
+}
+
+static void test_assr(data_t *data, igt_output_t *output)
+{
+       drmModeConnector *connector = output->config.connector;
+       int connector_type = connector->connector_type;
+       const char *aux_dev;
+       bool assr_supported = false, assr_enabled = false;
+       bool is_internal_display;
+
+       igt_info("Test ASSR on link %s\n", output->name);
+
+       aux_dev = find_aux_dev(data, output);
+       igt_info("Link %s aux %s\n", output->name, aux_dev);
+       igt_require_f(aux_dev, "Cannot find AUX device for link %s\n", output->name);
+
+       parse_dpcd(aux_dev, &assr_supported, &assr_enabled);
+
+       is_internal_display = get_internal_display_flag(data, output);
+
+       igt_info("Link %s internal: %d, ASSR supported: %d, ASSR enabled: %d\n",
+                       output->name,
+                       is_internal_display,
+                       assr_supported, assr_enabled);
+
+       present_visual_pattern(data, output);
+
+       if (connector_type == DRM_MODE_CONNECTOR_eDP ||
+               (connector_type == DRM_MODE_CONNECTOR_DisplayPort &&
+                is_internal_display))
+               igt_assert(assr_supported == assr_enabled);
+       else
+               igt_assert(!assr_enabled);
+}
+
+static void test_assr_links(data_t *data)
+{
+       for (int i = 0; i < data->display.n_outputs; ++i) {
+               drmModeConnector *connector = data->display.outputs[i].config.connector;
+               igt_output_t *output = &data->display.outputs[i];
+
+               if (connector->connection != DRM_MODE_CONNECTED)
+                       continue;
+
+               if (connector->connector_type != DRM_MODE_CONNECTOR_eDP &&
+                       connector->connector_type != DRM_MODE_CONNECTOR_DisplayPort)
+                       continue;
+
+               test_init(data);
+
+               test_assr(data, output);
+
+               test_fini(data);
+       }
+
+}
+
+igt_main
+{
+       data_t data;
+
+       igt_skip_on_simulation();
+
+       memset(&data, 0, sizeof(data));
+
+       igt_fixture
+       {
+               data.fd = drm_open_driver_master(DRIVER_AMDGPU);
+
+               kmstest_set_vt_graphics_mode();
+
+               igt_display_require(&data.display, data.fd);
+               igt_require(data.display.is_atomic);
+               igt_display_require_output(&data.display);
+       }
+
+       igt_describe("Test ASSR on connected DP/eDP links");
+       igt_subtest("assr-links")
+               test_assr_links(&data);
+
+       igt_fixture
+       {
+               igt_display_fini(&data.display);
+       }
+}

diff --git a/tests/amdgpu/meson.build b/tests/amdgpu/meson.build
index 84179410..1752cafb 100644
--- a/tests/amdgpu/meson.build
+++ b/tests/amdgpu/meson.build

@@ -10,6 +10,7 @@ if libdrm_amdgpu.found()
                          'amd_info',
                          'amd_prime',
                          'amd_module_load',
+                         'amd_assr',
                        ]
        amdgpu_deps += libdrm_amdgpu
 endif
--

2.32.0