RE: [PATCH i-g-t 5/5] tests/intel/xe_pat: Validate XA App Transient feature

Dandamudi, Priyanka
2026-03-03T13:11:07Z

> -----Original Message-----
> From: Auld, Matthew <matthew.auld@intel.com>
> Sent: 03 March 2026 04:08 PM
> To: Dandamudi, Priyanka <priyanka.dandamudi@intel.com>; Kempczynski,
> Zbigniew <zbigniew.kempczynski@intel.com>; igt-dev@lists.freedesktop.org
> Subject: Re: [PATCH i-g-t 5/5] tests/intel/xe_pat: Validate XA App Transient
> feature
>
> On 03/03/2026 04:38, priyanka.dandamudi@intel.com wrote:
> > From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> >
> > Test the scenarios when media is on/off.
> > When media is off/on, for xa app transient buffer, data should be
> > coherent between cpu and gpu. Coherency should be maintained from
> KMD
> > side irrespective of media engine on/off.
> >
> > v2: Added comment to explain the reason of forcewaking.
> > Added 2way also in the index along with XA.(Matt) Reordered
> > headers.(Kamil)
> >
> > Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > ---
> > tests/intel/xe_pat.c | 103
> +++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 103 insertions(+)
> >
> > diff --git a/tests/intel/xe_pat.c b/tests/intel/xe_pat.c index
> > aeb84dbb7..dbeb7c7d9 100644
> > --- a/tests/intel/xe_pat.c
> > +++ b/tests/intel/xe_pat.c
> > @@ -16,11 +16,17 @@
> > #include "igt.h"
> > #include "igt_syncobj.h"
> > #include "igt_vgem.h"
> > +#include "igt_configfs.h"
> > +#include "igt_device.h"
> > +#include "igt_fs.h"
> > +#include "igt_kmod.h"
> > +#include "igt_sysfs.h"
> > #include "intel_blt.h"
> > #include "intel_mocs.h"
> > #include "intel_pat.h"
> > #include "linux_scaffold.h"
> >
> > +#include "xe/xe_gt.h"
> > #include "xe/xe_ioctl.h"
> > #include "xe/xe_query.h"
> > #include "xe/xe_util.h"
> > @@ -29,6 +35,8 @@
> > #define XE_COH_AT_LEAST_1WAY 2
> >
> > static bool do_slow_check;
> > +static char bus_addr[NAME_MAX];
> > +static struct pci_device *pci_dev;
> >
> > static uint32_t create_object(int fd, int r, int size, uint16_t coh_mode,
> > bool force_cpu_wc);
> > @@ -1184,6 +1192,12 @@ const struct pat_index_entry
> bmg_g21_pat_index_modes[] = {
> > { NULL, 27, false, "c2-2way", XE_COH_AT_LEAST_1WAY },
> > };
> >
> > +const struct pat_index_entry xe3p_lpg_coherency_pat_index_modes[] = {
> > + { NULL, 18, false, "xa-l3-uc", XE_COH_NONE },
> > + { NULL, 19, false, "xa-l3-2way", XE_COH_AT_LEAST_1WAY },
>
> Nit: there is no 2way+xa, so the string here is not really accurate.
Got it, string name will update to "xa-l3-1way"
>
> > + { NULL, 2, false, "2way", XE_COH_AT_LEAST_1WAY },
> > +};
> > +
> > /*
> > * Depending on 2M/1G GTT pages we might trigger different PTE layouts
> for the
> > * PAT bits, so make sure we test with and without huge-pages. Also
> > ensure we @@ -1248,6 +1262,18 @@ static uint32_t create_object(int fd,
> int r, int size, uint16_t coh_mode,
> > * Description: Check some of the xe2 pat_index modes.
> > */
> >
> > +/**
> > + * SUBTEST: xa-app-transient-media-off
> > + * Test category: functionality test
> > + * Description: Check some of the xe4-lpg pat_index modes with media
> off.
> > + */
> > +
> > +/**
> > + * SUBTEST: xa-app-transient-media-on
> > + * Test category: functionality test
> > + * Description: Check some of the xe3p-lpg pat_index modes with media
> on.
> > + */
> > +
> > static void subtest_pat_index_modes_with_regions(int fd,
> > const struct pat_index_entry
> *modes_arr,
> > int n_modes)
> > @@ -1561,6 +1587,53 @@ static void false_sharing(int fd)
> > }
> > }
> >
> > +static void reset(int sig)
> > +{
> > + int configfs_fd;
> > +
> > + igt_kmod_unbind("xe", bus_addr);
> > +
> > + /* Drop all custom configfs settings from subtests */
> > + configfs_fd = igt_configfs_open("xe");
> > + if (configfs_fd >= 0)
> > + igt_fs_remove_dir(configfs_fd, bus_addr);
> > + close(configfs_fd);
> > +
> > + /* Bind again a clean driver with no custom settings */
> > + igt_kmod_bind("xe", bus_addr);
> > +}
> > +
> > +static void xa_app_transient_test(int configfs_device_fd, bool
> > +media_on) {
> > + int fd, fw_handle, gt;
> > +
> > + igt_kmod_unbind("xe", bus_addr);
> > +
> > + if (media_on)
> > + igt_assert(igt_sysfs_set(configfs_device_fd,
> > + "gt_types_allowed",
> "primary,media"));
> > + else
> > + igt_assert(igt_sysfs_set(configfs_device_fd,
> > + "gt_types_allowed", "primary"));
> > +
> > + igt_kmod_bind("xe", bus_addr);
> > +
> > + fd = drm_open_driver(DRIVER_XE);
> > +
> > + /* To prevent entering into rc6 for the duration of test. */
>
> "Prevent entering C6 for the duration of the test, since this can result in
> randomly flushing the entire device side caches, invalidating our XA testing."
>
Will update the comment like above.
> Reviewed-by: Matthew Auld <matthew.auld@intel.com>
>
> But please do keep an eye on:
> https://patchwork.freedesktop.org/patch/708272/?series=158017&rev=6
>
> Anything which claims to be rejected by uAPI we will want a negative test.
>
>
> > + fw_handle = igt_debugfs_open(fd, "forcewake_all", O_RDONLY);
> > + igt_require(fw_handle >= 0);
> > +
> > + subtest_pat_index_modes_with_regions(fd,
> xe3p_lpg_coherency_pat_index_modes,
> > +
> ARRAY_SIZE(xe3p_lpg_coherency_pat_index_modes));
> > +
> > + /* check status of c state, it should not be in c6 due to forcewake. */
> > + xe_for_each_gt(fd, gt)
> > + igt_assert(!xe_gt_is_in_c6(fd, gt));
> > +
> > + close(fw_handle);
> > +}
> > +
> > static int opt_handler(int opt, int opt_index, void *data)
> > {
> > switch (opt) {
> > @@ -1652,6 +1725,36 @@ int igt_main_args("V", NULL, help_str,
> opt_handler, NULL)
> > false_sharing(fd);
> > }
> >
> > + igt_subtest_group() {
> > + int configfs_fd, configfs_device_fd;
> > +
> > + igt_fixture() {
> > + igt_require(intel_graphics_ver(dev_id) == IP_VER(35,
> 10));
> > +
> > + pci_dev = igt_device_get_pci_device(fd);
> > + snprintf(bus_addr, sizeof(bus_addr),
> "%04x:%02x:%02x.%01x",
> > + pci_dev->domain, pci_dev->bus, pci_dev-
> >dev, pci_dev->func);
> > +
> > + configfs_fd = igt_configfs_open("xe");
> > + igt_require(configfs_fd != -1);
> > + configfs_device_fd = igt_fs_create_dir(configfs_fd,
> bus_addr,
> > + S_IRWXU |
> S_IRGRP | S_IXGRP |
> > + S_IROTH |
> S_IXOTH);
> > + igt_install_exit_handler(reset);
> > + }
> > +
> > + igt_subtest_with_dynamic("xa-app-transient-media-off")
> > + xa_app_transient_test(configfs_device_fd, false);
> > +
> > + igt_subtest_with_dynamic("xa-app-transient-media-on")
> > + xa_app_transient_test(configfs_device_fd, true);
> > +
> > + igt_fixture() {
> > + close(configfs_device_fd);
> > + close(configfs_fd);
> > + }
> > + }
> > +
> > igt_fixture()
> > drm_close_driver(fd);
> > }