[igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[priyanka.dandamudi]

From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>

New test named resize bar has been added which tests whether
bar gets resized with different supported sizes.

Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
---
 tests/i915/i915_module_load.c | 64 +++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
index f5f98acc2..b334ef612 100644
--- a/tests/i915/i915_module_load.c
+++ b/tests/i915/i915_module_load.c
@@ -37,6 +37,9 @@
 #include "igt_sysfs.h"
 #include "igt_core.h"
 
+#define BAR_SIZE_SHIFT 20
+#define BYTE 1024
+
 IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
 
 static void store_all(int i915)
@@ -236,6 +239,28 @@ hda_dynamic_debug(bool enable)
 	fclose(fp);
 }
 
+static int driver_load_unload(struct drm_i915_query_memory_regions **regions, uint32_t lmem_bar_size)
+{
+	int i915 = -1;
+	char lmem_bar[64];
+
+	igt_i915_driver_unload();
+	if (lmem_bar_size == 0)
+		igt_assert_eq(igt_i915_driver_load(NULL), 0);
+	else {
+		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
+		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
+	}
+
+	i915 = __drm_open_driver(DRIVER_INTEL);
+	igt_require_fd(i915);
+	igt_require(gem_has_lmem(i915));
+	*regions = gem_get_query_memory_regions(i915);
+	igt_require(*regions);
+
+	return i915;
+}
+
 igt_main
 {
 	igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
@@ -286,5 +311,44 @@ igt_main
 		/* inject_fault() leaves the module unloaded */
 	}
 
+	igt_subtest("resize-bar") {
+		struct drm_i915_query_memory_regions *regions;
+		struct drm_i915_memory_region_info *region;
+		uint32_t lmem_bar_size;
+		uint32_t small_bar;
+		bool bar_check = false;
+		int i915 = -1;
+
+		i915 = driver_load_unload(&regions, 0);
+
+		for (unsigned int i = 0; i < (regions)->num_regions; i++)
+			for_each_if(((region) = &(regions)->regions[i])->region.memory_class == I915_MEMORY_CLASS_DEVICE) {
+				lmem_bar_size = ceil((float)(region->probed_size >> BAR_SIZE_SHIFT)/BYTE)*BYTE;
+				small_bar = (region->rsvd1[0] >> BAR_SIZE_SHIFT);
+				if (small_bar < lmem_bar_size)
+					bar_check = true;
+			}
+		while (lmem_bar_size >= 256) {
+
+			close(i915);
+
+			i915 = driver_load_unload(&regions, lmem_bar_size);
+
+			for (unsigned int i = 0; i < (regions)->num_regions; i++)
+				for_each_if(((region) = &(regions)->regions[i])->region.memory_class == I915_MEMORY_CLASS_DEVICE) {
+					igt_assert_f(((region->probed_size >> BAR_SIZE_SHIFT) == lmem_bar_size),
+							 "Failed to set bar size");
+					if (bar_check)
+						igt_assert_f((small_bar == (region->rsvd1[0] >> BAR_SIZE_SHIFT)),
+								 "Small bar is not set properly");
+					else
+						igt_assert_f(region->probed_size == region->rsvd1[0], "Small bar and"
+								" lmem bar values need to be same");
+			}
+		lmem_bar_size = lmem_bar_size >> 1;
+		}
+		igt_i915_driver_unload();
+	}
+
 	/* Subtests should unload the module themselves if they use modparams */
 }
-- 
2.27.0

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Petri Latvala]

On Wed, Jun 15, 2022 at 11:11:46AM +0530, priyanka.dandamudi@intel.com wrote:
> From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> 
> New test named resize bar has been added which tests whether
> bar gets resized with different supported sizes.
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> ---
>  tests/i915/i915_module_load.c | 64 +++++++++++++++++++++++++++++++++++
>  1 file changed, 64 insertions(+)
> 
> diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
> index f5f98acc2..b334ef612 100644
> --- a/tests/i915/i915_module_load.c
> +++ b/tests/i915/i915_module_load.c
> @@ -37,6 +37,9 @@
>  #include "igt_sysfs.h"
>  #include "igt_core.h"
>  
> +#define BAR_SIZE_SHIFT 20
> +#define BYTE 1024
> +
>  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
>  
>  static void store_all(int i915)
> @@ -236,6 +239,28 @@ hda_dynamic_debug(bool enable)
>  	fclose(fp);
>  }
>  
> +static int driver_load_unload(struct drm_i915_query_memory_regions **regions, uint32_t lmem_bar_size)
> +{
> +	int i915 = -1;
> +	char lmem_bar[64];
> +
> +	igt_i915_driver_unload();
> +	if (lmem_bar_size == 0)
> +		igt_assert_eq(igt_i915_driver_load(NULL), 0);
> +	else {
> +		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> +		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> +	}
> +
> +	i915 = __drm_open_driver(DRIVER_INTEL);
> +	igt_require_fd(i915);
> +	igt_require(gem_has_lmem(i915));
> +	*regions = gem_get_query_memory_regions(i915);
> +	igt_require(*regions);
> +
> +	return i915;
> +}
> +
>  igt_main
>  {
>  	igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
> @@ -286,5 +311,44 @@ igt_main
>  		/* inject_fault() leaves the module unloaded */
>  	}
>  
> +	igt_subtest("resize-bar") {
> +		struct drm_i915_query_memory_regions *regions;
> +		struct drm_i915_memory_region_info *region;
> +		uint32_t lmem_bar_size;
> +		uint32_t small_bar;
> +		bool bar_check = false;
> +		int i915 = -1;
> +
> +		i915 = driver_load_unload(&regions, 0);

Before the unload, do this:

i915 = drm_open_driver(DRIVER_INTEL);
igt_require(gem_has_lmem(i915);
close(i915);

That way we can avoid an unnecessary reload cycle on integrated.

Which kernel version has the lmem_bar_size parameter? You might want
to check its existence too. gem_lmem_swapping has an example of how
it's done, with the param "lmem_size".


-- 
Petri Latvala



> +
> +		for (unsigned int i = 0; i < (regions)->num_regions; i++)
> +			for_each_if(((region) = &(regions)->regions[i])->region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> +				lmem_bar_size = ceil((float)(region->probed_size >> BAR_SIZE_SHIFT)/BYTE)*BYTE;
> +				small_bar = (region->rsvd1[0] >> BAR_SIZE_SHIFT);
> +				if (small_bar < lmem_bar_size)
> +					bar_check = true;
> +			}
> +		while (lmem_bar_size >= 256) {
> +
> +			close(i915);
> +
> +			i915 = driver_load_unload(&regions, lmem_bar_size);
> +
> +			for (unsigned int i = 0; i < (regions)->num_regions; i++)
> +				for_each_if(((region) = &(regions)->regions[i])->region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> +					igt_assert_f(((region->probed_size >> BAR_SIZE_SHIFT) == lmem_bar_size),
> +							 "Failed to set bar size");
> +					if (bar_check)
> +						igt_assert_f((small_bar == (region->rsvd1[0] >> BAR_SIZE_SHIFT)),
> +								 "Small bar is not set properly");
> +					else
> +						igt_assert_f(region->probed_size == region->rsvd1[0], "Small bar and"
> +								" lmem bar values need to be same");
> +			}
> +		lmem_bar_size = lmem_bar_size >> 1;
> +		}
> +		igt_i915_driver_unload();
> +	}
> +
>  	/* Subtests should unload the module themselves if they use modparams */
>  }
> -- 
> 2.27.0
> 

[igt-dev] ✗ Fi.CI.BUILD: failure for tests/i915/i915_module_load: Test resizable bar support

[Patchwork]

== Series Details ==

Series: tests/i915/i915_module_load: Test resizable bar support
URL   : https://patchwork.freedesktop.org/series/105141/
State : failure

== Summary ==

Applying: tests/i915/i915_module_load: Test resizable bar support
Using index info to reconstruct a base tree...
M	tests/i915/i915_module_load.c
Falling back to patching base and 3-way merge...
Auto-merging tests/i915/i915_module_load.c
CONFLICT (content): Merge conflict in tests/i915/i915_module_load.c
Patch failed at 0001 tests/i915/i915_module_load: Test resizable bar support
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Dandamudi, Priyanka]

> -----Original Message-----
> From: Latvala, Petri <petri.latvala@intel.com>
> Sent: 15 June 2022 12:09 PM
> To: Dandamudi, Priyanka <priyanka.dandamudi@intel.com>
> Cc: Auld, Matthew <matthew.auld@intel.com>; igt-dev@lists.freedesktop.org
> Subject: Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar
> support
> 
> On Wed, Jun 15, 2022 at 11:11:46AM +0530, priyanka.dandamudi@intel.com
> wrote:
> > From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> >
> > New test named resize bar has been added which tests whether bar gets
> > resized with different supported sizes.
> >
> > Cc: Matthew Auld <matthew.auld@intel.com>
> > Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > ---
> >  tests/i915/i915_module_load.c | 64
> > +++++++++++++++++++++++++++++++++++
> >  1 file changed, 64 insertions(+)
> >
> > diff --git a/tests/i915/i915_module_load.c
> > b/tests/i915/i915_module_load.c index f5f98acc2..b334ef612 100644
> > --- a/tests/i915/i915_module_load.c
> > +++ b/tests/i915/i915_module_load.c
> > @@ -37,6 +37,9 @@
> >  #include "igt_sysfs.h"
> >  #include "igt_core.h"
> >
> > +#define BAR_SIZE_SHIFT 20
> > +#define BYTE 1024
> > +
> >  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
> >
> >  static void store_all(int i915)
> > @@ -236,6 +239,28 @@ hda_dynamic_debug(bool enable)
> >  	fclose(fp);
> >  }
> >
> > +static int driver_load_unload(struct drm_i915_query_memory_regions
> > +**regions, uint32_t lmem_bar_size) {
> > +	int i915 = -1;
> > +	char lmem_bar[64];
> > +
> > +	igt_i915_driver_unload();
> > +	if (lmem_bar_size == 0)
> > +		igt_assert_eq(igt_i915_driver_load(NULL), 0);
> > +	else {
> > +		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> > +		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> > +	}
> > +
> > +	i915 = __drm_open_driver(DRIVER_INTEL);
> > +	igt_require_fd(i915);
> > +	igt_require(gem_has_lmem(i915));
> > +	*regions = gem_get_query_memory_regions(i915);
> > +	igt_require(*regions);
> > +
> > +	return i915;
> > +}
> > +
> >  igt_main
> >  {
> >  	igt_describe("Verify the basic functionality of i915 driver after
> > it's reloaded."); @@ -286,5 +311,44 @@ igt_main
> >  		/* inject_fault() leaves the module unloaded */
> >  	}
> >
> > +	igt_subtest("resize-bar") {
> > +		struct drm_i915_query_memory_regions *regions;
> > +		struct drm_i915_memory_region_info *region;
> > +		uint32_t lmem_bar_size;
> > +		uint32_t small_bar;
> > +		bool bar_check = false;
> > +		int i915 = -1;
> > +
> > +		i915 = driver_load_unload(&regions, 0);
> 
> Before the unload, do this:
> 
> i915 = drm_open_driver(DRIVER_INTEL);
> igt_require(gem_has_lmem(i915);
> close(i915);
> 
[Dandamudi, Priyanka] 
The above work iam doing in driver_load_unload method.

> That way we can avoid an unnecessary reload cycle on integrated.
> 
> Which kernel version has the lmem_bar_size parameter? You might want to
> check its existence too. gem_lmem_swapping has an example of how it's done,
> with the param "lmem_size".
> 
> 
> --
> Petri Latvala
> 
[Dandamudi, Priyanka] 
lmem_size will also allow to resize the bar eg:62MB which is not expected as 256MB is the minimum size.
lmem_bar_size is a new modparam which is being added from the driver side to test different supported sizes.
> 
> 
> > +
> > +		for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > +			for_each_if(((region) = &(regions)->regions[i])-
> >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > +				lmem_bar_size = ceil((float)(region-
> >probed_size >> BAR_SIZE_SHIFT)/BYTE)*BYTE;
> > +				small_bar = (region->rsvd1[0] >>
> BAR_SIZE_SHIFT);
> > +				if (small_bar < lmem_bar_size)
> > +					bar_check = true;
> > +			}
> > +		while (lmem_bar_size >= 256) {
> > +
> > +			close(i915);
> > +
> > +			i915 = driver_load_unload(&regions, lmem_bar_size);
> > +
> > +			for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > +				for_each_if(((region) = &(regions)->regions[i])-
> >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > +					igt_assert_f(((region->probed_size >>
> BAR_SIZE_SHIFT) == lmem_bar_size),
> > +							 "Failed to set bar
> size");
> > +					if (bar_check)
> > +						igt_assert_f((small_bar ==
> (region->rsvd1[0] >> BAR_SIZE_SHIFT)),
> > +								 "Small bar is
> not set properly");
> > +					else
> > +						igt_assert_f(region-
> >probed_size == region->rsvd1[0], "Small bar and"
> > +								" lmem bar
> values need to be same");
> > +			}
> > +		lmem_bar_size = lmem_bar_size >> 1;
> > +		}
> > +		igt_i915_driver_unload();
> > +	}
> > +
> >  	/* Subtests should unload the module themselves if they use
> modparams */
> >  }
> > --
> > 2.27.0
> >

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Petri Latvala]

On Wed, Jun 15, 2022 at 02:20:17PM +0300, Dandamudi, Priyanka wrote:
> 
> 
> > -----Original Message-----
> > From: Latvala, Petri <petri.latvala@intel.com>
> > Sent: 15 June 2022 12:09 PM
> > To: Dandamudi, Priyanka <priyanka.dandamudi@intel.com>
> > Cc: Auld, Matthew <matthew.auld@intel.com>; igt-dev@lists.freedesktop.org
> > Subject: Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar
> > support
> >
> > On Wed, Jun 15, 2022 at 11:11:46AM +0530, priyanka.dandamudi@intel.com
> > wrote:
> > > From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > >
> > > New test named resize bar has been added which tests whether bar gets
> > > resized with different supported sizes.
> > >
> > > Cc: Matthew Auld <matthew.auld@intel.com>
> > > Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > > ---
> > >  tests/i915/i915_module_load.c | 64
> > > +++++++++++++++++++++++++++++++++++
> > >  1 file changed, 64 insertions(+)
> > >
> > > diff --git a/tests/i915/i915_module_load.c
> > > b/tests/i915/i915_module_load.c index f5f98acc2..b334ef612 100644
> > > --- a/tests/i915/i915_module_load.c
> > > +++ b/tests/i915/i915_module_load.c
> > > @@ -37,6 +37,9 @@
> > >  #include "igt_sysfs.h"
> > >  #include "igt_core.h"
> > >
> > > +#define BAR_SIZE_SHIFT 20
> > > +#define BYTE 1024
> > > +
> > >  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
> > >
> > >  static void store_all(int i915)
> > > @@ -236,6 +239,28 @@ hda_dynamic_debug(bool enable)
> > >     fclose(fp);
> > >  }
> > >
> > > +static int driver_load_unload(struct drm_i915_query_memory_regions
> > > +**regions, uint32_t lmem_bar_size) {
> > > +   int i915 = -1;
> > > +   char lmem_bar[64];
> > > +
> > > +   igt_i915_driver_unload();
> > > +   if (lmem_bar_size == 0)
> > > +           igt_assert_eq(igt_i915_driver_load(NULL), 0);
> > > +   else {
> > > +           sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> > > +           igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> > > +   }
> > > +
> > > +   i915 = __drm_open_driver(DRIVER_INTEL);
> > > +   igt_require_fd(i915);
> > > +   igt_require(gem_has_lmem(i915));
> > > +   *regions = gem_get_query_memory_regions(i915);
> > > +   igt_require(*regions);
> > > +
> > > +   return i915;
> > > +}
> > > +
> > >  igt_main
> > >  {
> > >     igt_describe("Verify the basic functionality of i915 driver after
> > > it's reloaded."); @@ -286,5 +311,44 @@ igt_main
> > >             /* inject_fault() leaves the module unloaded */
> > >     }
> > >
> > > +   igt_subtest("resize-bar") {
> > > +           struct drm_i915_query_memory_regions *regions;
> > > +           struct drm_i915_memory_region_info *region;
> > > +           uint32_t lmem_bar_size;
> > > +           uint32_t small_bar;
> > > +           bool bar_check = false;
> > > +           int i915 = -1;
> > > +
> > > +           i915 = driver_load_unload(&regions, 0);
> >
> > Before the unload, do this:
> >
> > i915 = drm_open_driver(DRIVER_INTEL);
> > igt_require(gem_has_lmem(i915);
> > close(i915);
> >
> [Dandamudi, Priyanka]
> The above work iam doing in driver_load_unload method.

There the check is done after the unload. What I want is checking for
lmem before unload so we can avoid the unload, on integrated.

> 
> > That way we can avoid an unnecessary reload cycle on integrated.
> >
> > Which kernel version has the lmem_bar_size parameter? You might want to
> > check its existence too. gem_lmem_swapping has an example of how it's done,
> > with the param "lmem_size".
> >
> >
> > --
> > Petri Latvala
> >
> [Dandamudi, Priyanka]
> lmem_size will also allow to resize the bar eg:62MB which is not expected as 256MB is the minimum size.
> lmem_bar_size is a new modparam which is being added from the driver side to test different supported sizes.

Yes, I didn't mean to use the same modparam. I meant to handle
checking for existence in the same way it's done for that other param.


-- 
Petri Latvala


> >
> >
> > > +
> > > +           for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > > +                   for_each_if(((region) = &(regions)->regions[i])-
> > >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > > +                           lmem_bar_size = ceil((float)(region-
> > >probed_size >> BAR_SIZE_SHIFT)/BYTE)*BYTE;
> > > +                           small_bar = (region->rsvd1[0] >>
> > BAR_SIZE_SHIFT);
> > > +                           if (small_bar < lmem_bar_size)
> > > +                                   bar_check = true;
> > > +                   }
> > > +           while (lmem_bar_size >= 256) {
> > > +
> > > +                   close(i915);
> > > +
> > > +                   i915 = driver_load_unload(&regions, lmem_bar_size);
> > > +
> > > +                   for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > > +                           for_each_if(((region) = &(regions)->regions[i])-
> > >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > > +                                   igt_assert_f(((region->probed_size >>
> > BAR_SIZE_SHIFT) == lmem_bar_size),
> > > +                                                    "Failed to set bar
> > size");
> > > +                                   if (bar_check)
> > > +                                           igt_assert_f((small_bar ==
> > (region->rsvd1[0] >> BAR_SIZE_SHIFT)),
> > > +                                                            "Small bar is
> > not set properly");
> > > +                                   else
> > > +                                           igt_assert_f(region-
> > >probed_size == region->rsvd1[0], "Small bar and"
> > > +                                                           " lmem bar
> > values need to be same");
> > > +                   }
> > > +           lmem_bar_size = lmem_bar_size >> 1;
> > > +           }
> > > +           igt_i915_driver_unload();
> > > +   }
> > > +
> > >     /* Subtests should unload the module themselves if they use
> > modparams */
> > >  }
> > > --
> > > 2.27.0
> > >

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Dandamudi, Priyanka]

> -----Original Message-----
> From: Latvala, Petri <petri.latvala@intel.com>
> Sent: 15 June 2022 07:57 PM
> To: Dandamudi, Priyanka <priyanka.dandamudi@intel.com>
> Cc: igt-dev@lists.freedesktop.org
> Subject: Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable
> bar support
> 
> On Wed, Jun 15, 2022 at 02:20:17PM +0300, Dandamudi, Priyanka wrote:
> >
> >
> > > -----Original Message-----
> > > From: Latvala, Petri <petri.latvala@intel.com>
> > > Sent: 15 June 2022 12:09 PM
> > > To: Dandamudi, Priyanka <priyanka.dandamudi@intel.com>
> > > Cc: Auld, Matthew <matthew.auld@intel.com>;
> > > igt-dev@lists.freedesktop.org
> > > Subject: Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test
> > > resizable bar support
> > >
> > > On Wed, Jun 15, 2022 at 11:11:46AM +0530,
> > > priyanka.dandamudi@intel.com
> > > wrote:
> > > > From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > > >
> > > > New test named resize bar has been added which tests whether bar
> > > > gets resized with different supported sizes.
> > > >
> > > > Cc: Matthew Auld <matthew.auld@intel.com>
> > > > Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> > > > ---
> > > >  tests/i915/i915_module_load.c | 64
> > > > +++++++++++++++++++++++++++++++++++
> > > >  1 file changed, 64 insertions(+)
> > > >
> > > > diff --git a/tests/i915/i915_module_load.c
> > > > b/tests/i915/i915_module_load.c index f5f98acc2..b334ef612 100644
> > > > --- a/tests/i915/i915_module_load.c
> > > > +++ b/tests/i915/i915_module_load.c
> > > > @@ -37,6 +37,9 @@
> > > >  #include "igt_sysfs.h"
> > > >  #include "igt_core.h"
> > > >
> > > > +#define BAR_SIZE_SHIFT 20
> > > > +#define BYTE 1024
> > > > +
> > > >  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
> > > >
> > > >  static void store_all(int i915)
> > > > @@ -236,6 +239,28 @@ hda_dynamic_debug(bool enable)
> > > >     fclose(fp);
> > > >  }
> > > >
> > > > +static int driver_load_unload(struct
> > > > +drm_i915_query_memory_regions **regions, uint32_t
> lmem_bar_size) {
> > > > +   int i915 = -1;
> > > > +   char lmem_bar[64];
> > > > +
> > > > +   igt_i915_driver_unload();
> > > > +   if (lmem_bar_size == 0)
> > > > +           igt_assert_eq(igt_i915_driver_load(NULL), 0);
> > > > +   else {
> > > > +           sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> > > > +           igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> > > > +   }
> > > > +
> > > > +   i915 = __drm_open_driver(DRIVER_INTEL);
> > > > +   igt_require_fd(i915);
> > > > +   igt_require(gem_has_lmem(i915));
> > > > +   *regions = gem_get_query_memory_regions(i915);
> > > > +   igt_require(*regions);
> > > > +
> > > > +   return i915;
> > > > +}
> > > > +
> > > >  igt_main
> > > >  {
> > > >     igt_describe("Verify the basic functionality of i915 driver
> > > > after it's reloaded."); @@ -286,5 +311,44 @@ igt_main
> > > >             /* inject_fault() leaves the module unloaded */
> > > >     }
> > > >
> > > > +   igt_subtest("resize-bar") {
> > > > +           struct drm_i915_query_memory_regions *regions;
> > > > +           struct drm_i915_memory_region_info *region;
> > > > +           uint32_t lmem_bar_size;
> > > > +           uint32_t small_bar;
> > > > +           bool bar_check = false;
> > > > +           int i915 = -1;
> > > > +
> > > > +           i915 = driver_load_unload(&regions, 0);
> > >
> > > Before the unload, do this:
> > >
> > > i915 = drm_open_driver(DRIVER_INTEL);
> > > igt_require(gem_has_lmem(i915); close(i915);
> > >
> > [Dandamudi, Priyanka]
> > The above work iam doing in driver_load_unload method.
> 
> There the check is done after the unload. What I want is checking for lmem
> before unload so we can avoid the unload, on integrated.
> 
> >
> > > That way we can avoid an unnecessary reload cycle on integrated.
> > >
> > > Which kernel version has the lmem_bar_size parameter? You might want
> > > to check its existence too. gem_lmem_swapping has an example of how
> > > it's done, with the param "lmem_size".
> > >
> > >
> > > --
> > > Petri Latvala
> > >
> > [Dandamudi, Priyanka]
> > lmem_size will also allow to resize the bar eg:62MB which is not expected
> as 256MB is the minimum size.
> > lmem_bar_size is a new modparam which is being added from the driver
> side to test different supported sizes.
> 
> Yes, I didn't mean to use the same modparam. I meant to handle checking
> for existence in the same way it's done for that other param.
> 
> 
> --
> Petri Latvala
[Dandamudi, Priyanka] 
Will incorporate the suggested changes in next version. Thanks
> 
> 
> > >
> > >
> > > > +
> > > > +           for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > > > +                   for_each_if(((region) = &(regions)->regions[i])-
> > > >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > > > +                           lmem_bar_size = ceil((float)(region-
> > > >probed_size >> BAR_SIZE_SHIFT)/BYTE)*BYTE;
> > > > +                           small_bar = (region->rsvd1[0] >>
> > > BAR_SIZE_SHIFT);
> > > > +                           if (small_bar < lmem_bar_size)
> > > > +                                   bar_check = true;
> > > > +                   }
> > > > +           while (lmem_bar_size >= 256) {
> > > > +
> > > > +                   close(i915);
> > > > +
> > > > +                   i915 = driver_load_unload(&regions, lmem_bar_size);
> > > > +
> > > > +                   for (unsigned int i = 0; i < (regions)->num_regions; i++)
> > > > +                           for_each_if(((region) = &(regions)->regions[i])-
> > > >region.memory_class == I915_MEMORY_CLASS_DEVICE) {
> > > > +                                   igt_assert_f(((region->probed_size >>
> > > BAR_SIZE_SHIFT) == lmem_bar_size),
> > > > +                                                    "Failed to set bar
> > > size");
> > > > +                                   if (bar_check)
> > > > +                                           igt_assert_f((small_bar ==
> > > (region->rsvd1[0] >> BAR_SIZE_SHIFT)),
> > > > +                                                            "Small bar is
> > > not set properly");
> > > > +                                   else
> > > > +                                           igt_assert_f(region-
> > > >probed_size == region->rsvd1[0], "Small bar and"
> > > > +                                                           " lmem bar
> > > values need to be same");
> > > > +                   }
> > > > +           lmem_bar_size = lmem_bar_size >> 1;
> > > > +           }
> > > > +           igt_i915_driver_unload();
> > > > +   }
> > > > +
> > > >     /* Subtests should unload the module themselves if they use
> > > modparams */
> > > >  }
> > > > --
> > > > 2.27.0
> > > >

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Matthew Auld]

On Thu, 16 Jun 2022 at 13:16, <priyanka.dandamudi@intel.com> wrote:
>
> From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
>
> New test named resize bar has been added which tests whether
> bar gets resized with different supported sizes.
>
> v2: Added code to check for bad bar sizes.
> Modified code to check for support of lmem_bar_size modparam.(Petri)
>
> Note:Test gets executed when
> 1. modparam lmem_bar_size gets added.
> 2. small bar bits gets enabled.
>
> Cc: Matthew Auld <matthew.auld@intel.com>
> Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> ---
>  tests/i915/i915_module_load.c | 89 +++++++++++++++++++++++++++++++++++
>  1 file changed, 89 insertions(+)
>
> diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
> index f5f98acc2..5a653711b 100644
> --- a/tests/i915/i915_module_load.c
> +++ b/tests/i915/i915_module_load.c
> @@ -31,12 +31,17 @@
>  #include <fcntl.h>
>
>  #include "i915/gem_create.h"
> +#include "i915/gem.h"
>  #include "igt_debugfs.h"
>  #include "igt_aux.h"
>  #include "igt_kmod.h"
>  #include "igt_sysfs.h"
>  #include "igt_core.h"
>
> +#define BAR_SIZE_SHIFT 20
> +#define MIN_BAR_SIZE 256
> +#define BYTE 1024
> +
>  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
>
>  static void store_all(int i915)
> @@ -236,6 +241,48 @@ hda_dynamic_debug(bool enable)
>         fclose(fp);
>  }
>
> +static uint32_t  driver_load_unload(uint32_t lmem_bar_size, bool check_support)

driver_load_with_lmem_bar_size(size_mb, check_support)

?

> +{
> +       struct drm_i915_query_memory_regions *regions;
> +       struct drm_i915_memory_region_info *region;
> +       int i915 = -1;
> +       char lmem_bar[64];
> +
> +       igt_i915_driver_unload();
> +       if (lmem_bar_size == 0)
> +               igt_assert_eq(igt_i915_driver_load(NULL), 0);
> +       else {
> +               sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> +               igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> +       }
> +
> +       i915 = __drm_open_driver(DRIVER_INTEL);
> +       igt_require_fd(i915);
> +       igt_require_gem(i915);
> +       igt_require(gem_has_lmem(i915));
> +
> +       if (check_support) {
> +               char *tmp;
> +
> +               tmp = __igt_params_get(i915, "lmem_bar_size");
> +               if (!tmp)
> +                       igt_skip("lmem_bar_size modparam not supported on this kernel."
> +                                       "Skipping the test.");

We don't normally split long lines if it's just a string.

> +               free(tmp);
> +       }
> +
> +       regions = gem_get_query_memory_regions(i915);
> +       igt_require(regions);
> +
> +       for (unsigned int i = 0; i < (regions)->num_regions; i++)
> +               for_each_if(((region) = &(regions)->regions[i])->region.memory_class ==
> +                               I915_MEMORY_CLASS_DEVICE)

I guess we need to add a skip here if the cpu_size is zero, which
would indicate an older kernel?

Also for_each_memory_region() is a lot nicer here.

You just need: https://patchwork.freedesktop.org/patch/490396/?series=104368&rev=2

> +                       lmem_bar_size = (region->rsvd1[0] >> BAR_SIZE_SHIFT);

It's a bit unclear how lmem_bar_size would work on multi-tile,
assuming we even care. One of the tiles would have
probed_cpu_visible_size = 0, which likely leads to failing to load the
module, since I assume we always require at least some amount of
per-tile lmem that can be accessed by the CPU during initialization. I
think for now make the test skip if we detect more than a single lmem
instance?

> +       close(i915);
> +
> +       return lmem_bar_size;
> +}
> +
>  igt_main
>  {
>         igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
> @@ -285,6 +332,48 @@ igt_main
>
>                 /* inject_fault() leaves the module unloaded */
>         }
> +       igt_subtest("resize-bar") {
> +               uint32_t result_bar_size;
> +               uint32_t lmem_bar_size;
> +               int i915 = -1;
> +
> +               if (igt_kmod_is_loaded("i915")) {
> +                       i915 = __drm_open_driver(DRIVER_INTEL);
> +                       igt_require_fd(i915);
> +                       igt_require_gem(i915);
> +                       igt_require(gem_has_lmem(i915));
> +                       close(i915);
> +               }
> +
> +               /* Test for lmem_bar_size modparam support */
> +               lmem_bar_size = driver_load_unload(MIN_BAR_SIZE, true);
> +               igt_assert_eq(lmem_bar_size, MIN_BAR_SIZE);
> +
> +               lmem_bar_size = driver_load_unload(0, false);
> +
> +               lmem_bar_size = ceil((float)(lmem_bar_size)/BYTE)*BYTE;

Shouldn't this be rounddown_pow_of_two() ?

> +
> +               igt_skip_on_f(lmem_bar_size == MIN_BAR_SIZE, "Bar is already set to minimum size.");
> +
> +               while (lmem_bar_size > MIN_BAR_SIZE) {
> +                       lmem_bar_size = lmem_bar_size >> 1;
> +
> +                       result_bar_size = driver_load_unload(lmem_bar_size, false);
> +
> +                       igt_assert_f(lmem_bar_size == result_bar_size, "Bar couldn't be resized.");
> +               }
> +
> +               /* Test with unsupported sizes */
> +               lmem_bar_size = 80;
> +               result_bar_size = driver_load_unload(lmem_bar_size, false);
> +               igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
> +
> +               lmem_bar_size = 16400;
> +               result_bar_size = driver_load_unload(lmem_bar_size, false);
> +               igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
> +
> +               igt_i915_driver_unload();
> +       }
>
>         /* Subtests should unload the module themselves if they use modparams */
>  }
> --
> 2.27.0
>

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Kamil Konieczny]

Hi Priyanka,

On 2022-06-16 at 17:35:58 +0530, priyanka.dandamudi@intel.com wrote:
> From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> 
> New test named resize bar has been added which tests whether
> bar gets resized with different supported sizes.
> 
> v2: Added code to check for bad bar sizes.
> Modified code to check for support of lmem_bar_size modparam.(Petri)
> 
> Note:Test gets executed when
> 1. modparam lmem_bar_size gets added.
> 2. small bar bits gets enabled.
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> ---
>  tests/i915/i915_module_load.c | 89 +++++++++++++++++++++++++++++++++++
>  1 file changed, 89 insertions(+)
> 
> diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
> index f5f98acc2..5a653711b 100644
> --- a/tests/i915/i915_module_load.c
> +++ b/tests/i915/i915_module_load.c
> @@ -31,12 +31,17 @@
>  #include <fcntl.h>
>  
>  #include "i915/gem_create.h"
> +#include "i915/gem.h"
>  #include "igt_debugfs.h"
>  #include "igt_aux.h"
>  #include "igt_kmod.h"
>  #include "igt_sysfs.h"
>  #include "igt_core.h"
>  
> +#define BAR_SIZE_SHIFT 20
> +#define MIN_BAR_SIZE 256
> +#define BYTE 1024
> +
>  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
>  
>  static void store_all(int i915)
> @@ -236,6 +241,48 @@ hda_dynamic_debug(bool enable)
>  	fclose(fp);
>  }
>  
> +static uint32_t  driver_load_unload(uint32_t lmem_bar_size, bool check_support)
> +{
> +	struct drm_i915_query_memory_regions *regions;
> +	struct drm_i915_memory_region_info *region;
> +	int i915 = -1;
> +	char lmem_bar[64];
> +
> +	igt_i915_driver_unload();
> +	if (lmem_bar_size == 0)
> +		igt_assert_eq(igt_i915_driver_load(NULL), 0);
> +	else {
> +		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> +		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> +	}
> +
> +	i915 = __drm_open_driver(DRIVER_INTEL);
> +	igt_require_fd(i915);
> +	igt_require_gem(i915);
> +	igt_require(gem_has_lmem(i915));
> +
> +	if (check_support) {
> +		char *tmp;
> +
> +		tmp = __igt_params_get(i915, "lmem_bar_size");
> +		if (!tmp)
> +			igt_skip("lmem_bar_size modparam not supported on this kernel."
> +					"Skipping the test.");
> +		free(tmp);
> +	}
> +
> +	regions = gem_get_query_memory_regions(i915);
> +	igt_require(regions);
> +
> +	for (unsigned int i = 0; i < (regions)->num_regions; i++)
> +		for_each_if(((region) = &(regions)->regions[i])->region.memory_class ==
> +				I915_MEMORY_CLASS_DEVICE)
> +			lmem_bar_size = (region->rsvd1[0] >> BAR_SIZE_SHIFT);
> +	close(i915);
> +
> +	return lmem_bar_size;
> +}
> +
>  igt_main
>  {
>  	igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
> @@ -285,6 +332,48 @@ igt_main
>  
>  		/* inject_fault() leaves the module unloaded */
>  	}

Please add newline here and also add description to each new
test you add.

Regards,
Kamil

> +	igt_subtest("resize-bar") {
> +		uint32_t result_bar_size;
> +		uint32_t lmem_bar_size;
> +		int i915 = -1;
> +
> +		if (igt_kmod_is_loaded("i915")) {
> +			i915 = __drm_open_driver(DRIVER_INTEL);
> +			igt_require_fd(i915);
> +			igt_require_gem(i915);
> +			igt_require(gem_has_lmem(i915));
> +			close(i915);
> +		}
> +
> +		/* Test for lmem_bar_size modparam support */
> +		lmem_bar_size = driver_load_unload(MIN_BAR_SIZE, true);
> +		igt_assert_eq(lmem_bar_size, MIN_BAR_SIZE);
> +
> +		lmem_bar_size = driver_load_unload(0, false);
> +
> +		lmem_bar_size = ceil((float)(lmem_bar_size)/BYTE)*BYTE;
> +
> +		igt_skip_on_f(lmem_bar_size == MIN_BAR_SIZE, "Bar is already set to minimum size.");
> +
> +		while (lmem_bar_size > MIN_BAR_SIZE) {
> +			lmem_bar_size = lmem_bar_size >> 1;
> +
> +			result_bar_size = driver_load_unload(lmem_bar_size, false);
> +
> +			igt_assert_f(lmem_bar_size == result_bar_size, "Bar couldn't be resized.");
> +		}
> +
> +		/* Test with unsupported sizes */
> +		lmem_bar_size = 80;
> +		result_bar_size = driver_load_unload(lmem_bar_size, false);
> +		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
> +
> +		lmem_bar_size = 16400;
> +		result_bar_size = driver_load_unload(lmem_bar_size, false);
> +		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
> +
> +		igt_i915_driver_unload();
> +	}
>  
>  	/* Subtests should unload the module themselves if they use modparams */
>  }
> -- 
> 2.27.0
> 

Re: [igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[Petri Latvala]

On Thu, Jun 16, 2022 at 05:35:58PM +0530, priyanka.dandamudi@intel.com wrote:
> From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> 
> New test named resize bar has been added which tests whether
> bar gets resized with different supported sizes.
> 
> v2: Added code to check for bad bar sizes.
> Modified code to check for support of lmem_bar_size modparam.(Petri)
> 
> Note:Test gets executed when
> 1. modparam lmem_bar_size gets added.
> 2. small bar bits gets enabled.
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> ---
>  tests/i915/i915_module_load.c | 89 +++++++++++++++++++++++++++++++++++
>  1 file changed, 89 insertions(+)
> 
> diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
> index f5f98acc2..5a653711b 100644
> --- a/tests/i915/i915_module_load.c
> +++ b/tests/i915/i915_module_load.c
> @@ -31,12 +31,17 @@
>  #include <fcntl.h>
>  
>  #include "i915/gem_create.h"
> +#include "i915/gem.h"
>  #include "igt_debugfs.h"
>  #include "igt_aux.h"
>  #include "igt_kmod.h"
>  #include "igt_sysfs.h"
>  #include "igt_core.h"
>  
> +#define BAR_SIZE_SHIFT 20
> +#define MIN_BAR_SIZE 256
> +#define BYTE 1024
> +
>  IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
>  
>  static void store_all(int i915)
> @@ -236,6 +241,48 @@ hda_dynamic_debug(bool enable)
>  	fclose(fp);
>  }
>  
> +static uint32_t  driver_load_unload(uint32_t lmem_bar_size, bool check_support)
> +{
> +	struct drm_i915_query_memory_regions *regions;
> +	struct drm_i915_memory_region_info *region;
> +	int i915 = -1;
> +	char lmem_bar[64];
> +
> +	igt_i915_driver_unload();
> +	if (lmem_bar_size == 0)
> +		igt_assert_eq(igt_i915_driver_load(NULL), 0);
> +	else {
> +		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
> +		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
> +	}
> +
> +	i915 = __drm_open_driver(DRIVER_INTEL);
> +	igt_require_fd(i915);
> +	igt_require_gem(i915);
> +	igt_require(gem_has_lmem(i915));
> +
> +	if (check_support) {
> +		char *tmp;
> +
> +		tmp = __igt_params_get(i915, "lmem_bar_size");
> +		if (!tmp)
> +			igt_skip("lmem_bar_size modparam not supported on this kernel."
> +					"Skipping the test.");
> +		free(tmp);
> +	}
> +
> +	regions = gem_get_query_memory_regions(i915);
> +	igt_require(regions);
> +
> +	for (unsigned int i = 0; i < (regions)->num_regions; i++)
> +		for_each_if(((region) = &(regions)->regions[i])->region.memory_class ==
> +				I915_MEMORY_CLASS_DEVICE)
> +			lmem_bar_size = (region->rsvd1[0] >> BAR_SIZE_SHIFT);
> +	close(i915);
> +
> +	return lmem_bar_size;
> +}
> +
>  igt_main
>  {
>  	igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
> @@ -285,6 +332,48 @@ igt_main
>  
>  		/* inject_fault() leaves the module unloaded */
>  	}
> +	igt_subtest("resize-bar") {
> +		uint32_t result_bar_size;
> +		uint32_t lmem_bar_size;
> +		int i915 = -1;
> +
> +		if (igt_kmod_is_loaded("i915")) {
> +			i915 = __drm_open_driver(DRIVER_INTEL);
> +			igt_require_fd(i915);
> +			igt_require_gem(i915);
> +			igt_require(gem_has_lmem(i915));
> +			close(i915);
> +		}
> +
> +		/* Test for lmem_bar_size modparam support */
> +		lmem_bar_size = driver_load_unload(MIN_BAR_SIZE, true);
> +		igt_assert_eq(lmem_bar_size, MIN_BAR_SIZE);
> +
> +		lmem_bar_size = driver_load_unload(0, false);
> +
> +		lmem_bar_size = ceil((float)(lmem_bar_size)/BYTE)*BYTE;
> +
> +		igt_skip_on_f(lmem_bar_size == MIN_BAR_SIZE, "Bar is already set to minimum size.");
> +
> +		while (lmem_bar_size > MIN_BAR_SIZE) {
> +			lmem_bar_size = lmem_bar_size >> 1;
> +
> +			result_bar_size = driver_load_unload(lmem_bar_size, false);
> +
> +			igt_assert_f(lmem_bar_size == result_bar_size, "Bar couldn't be resized.");
> +		}
> +
> +		/* Test with unsupported sizes */
> +		lmem_bar_size = 80;
> +		result_bar_size = driver_load_unload(lmem_bar_size, false);
> +		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
> +
> +		lmem_bar_size = 16400;
> +		result_bar_size = driver_load_unload(lmem_bar_size, false);
> +		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");

All these assert and skip messages need to end in \n


-- 
Petri Latvala



> +
> +		igt_i915_driver_unload();
> +	}
>  
>  	/* Subtests should unload the module themselves if they use modparams */
>  }
> -- 
> 2.27.0
> 

[igt-dev] [PATCH] tests/i915/i915_module_load: Test resizable bar support

[priyanka.dandamudi]

From: Priyanka Dandamudi <priyanka.dandamudi@intel.com>

New test named resize bar has been added which tests whether
bar gets resized with different supported sizes.

v2: Added code to check for bad bar sizes.
Modified code to check for support of lmem_bar_size modparam.(Petri)

Note:Test gets executed when
1. modparam lmem_bar_size gets added.
2. small bar bits gets enabled.

Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
---
 tests/i915/i915_module_load.c | 89 +++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
index f5f98acc2..5a653711b 100644
--- a/tests/i915/i915_module_load.c
+++ b/tests/i915/i915_module_load.c
@@ -31,12 +31,17 @@
 #include <fcntl.h>
 
 #include "i915/gem_create.h"
+#include "i915/gem.h"
 #include "igt_debugfs.h"
 #include "igt_aux.h"
 #include "igt_kmod.h"
 #include "igt_sysfs.h"
 #include "igt_core.h"
 
+#define BAR_SIZE_SHIFT 20
+#define MIN_BAR_SIZE 256
+#define BYTE 1024
+
 IGT_TEST_DESCRIPTION("Tests the i915 module loading.");
 
 static void store_all(int i915)
@@ -236,6 +241,48 @@ hda_dynamic_debug(bool enable)
 	fclose(fp);
 }
 
+static uint32_t  driver_load_unload(uint32_t lmem_bar_size, bool check_support)
+{
+	struct drm_i915_query_memory_regions *regions;
+	struct drm_i915_memory_region_info *region;
+	int i915 = -1;
+	char lmem_bar[64];
+
+	igt_i915_driver_unload();
+	if (lmem_bar_size == 0)
+		igt_assert_eq(igt_i915_driver_load(NULL), 0);
+	else {
+		sprintf(lmem_bar, "lmem_bar_size=%u", lmem_bar_size);
+		igt_assert_eq(igt_i915_driver_load(lmem_bar), 0);
+	}
+
+	i915 = __drm_open_driver(DRIVER_INTEL);
+	igt_require_fd(i915);
+	igt_require_gem(i915);
+	igt_require(gem_has_lmem(i915));
+
+	if (check_support) {
+		char *tmp;
+
+		tmp = __igt_params_get(i915, "lmem_bar_size");
+		if (!tmp)
+			igt_skip("lmem_bar_size modparam not supported on this kernel."
+					"Skipping the test.");
+		free(tmp);
+	}
+
+	regions = gem_get_query_memory_regions(i915);
+	igt_require(regions);
+
+	for (unsigned int i = 0; i < (regions)->num_regions; i++)
+		for_each_if(((region) = &(regions)->regions[i])->region.memory_class ==
+				I915_MEMORY_CLASS_DEVICE)
+			lmem_bar_size = (region->rsvd1[0] >> BAR_SIZE_SHIFT);
+	close(i915);
+
+	return lmem_bar_size;
+}
+
 igt_main
 {
 	igt_describe("Verify the basic functionality of i915 driver after it's reloaded.");
@@ -285,6 +332,48 @@ igt_main
 
 		/* inject_fault() leaves the module unloaded */
 	}
+	igt_subtest("resize-bar") {
+		uint32_t result_bar_size;
+		uint32_t lmem_bar_size;
+		int i915 = -1;
+
+		if (igt_kmod_is_loaded("i915")) {
+			i915 = __drm_open_driver(DRIVER_INTEL);
+			igt_require_fd(i915);
+			igt_require_gem(i915);
+			igt_require(gem_has_lmem(i915));
+			close(i915);
+		}
+
+		/* Test for lmem_bar_size modparam support */
+		lmem_bar_size = driver_load_unload(MIN_BAR_SIZE, true);
+		igt_assert_eq(lmem_bar_size, MIN_BAR_SIZE);
+
+		lmem_bar_size = driver_load_unload(0, false);
+
+		lmem_bar_size = ceil((float)(lmem_bar_size)/BYTE)*BYTE;
+
+		igt_skip_on_f(lmem_bar_size == MIN_BAR_SIZE, "Bar is already set to minimum size.");
+
+		while (lmem_bar_size > MIN_BAR_SIZE) {
+			lmem_bar_size = lmem_bar_size >> 1;
+
+			result_bar_size = driver_load_unload(lmem_bar_size, false);
+
+			igt_assert_f(lmem_bar_size == result_bar_size, "Bar couldn't be resized.");
+		}
+
+		/* Test with unsupported sizes */
+		lmem_bar_size = 80;
+		result_bar_size = driver_load_unload(lmem_bar_size, false);
+		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
+
+		lmem_bar_size = 16400;
+		result_bar_size = driver_load_unload(lmem_bar_size, false);
+		igt_assert_f(lmem_bar_size != result_bar_size, "Bar resized to unsupported size.");
+
+		igt_i915_driver_unload();
+	}
 
 	/* Subtests should unload the module themselves if they use modparams */
 }
-- 
2.27.0