diff mbox series

[v2] drm/xe/fbdev: Limit the usage of stolen for LNL+

Message ID 20240714205659.3672665-1-uma.shankar@intel.com (mailing list archive)
State New, archived
Headers show
Series [v2] drm/xe/fbdev: Limit the usage of stolen for LNL+ | expand

Commit Message

Shankar, Uma July 14, 2024, 8:56 p.m. UTC
As per recommendation in the workarounds:
WA_22019338487

There is an issue with accessing Stolen memory pages due a
hardware limitation. Limit the usage of stolen memory for
fbdev for LNL+. Don't use BIOS FB from stolen on LNL+ and
assign the same from system memory.

v2: Corrected the WA Number, limited WA to LNL and
    Adopted XE_WA framework as suggested by Lucas and Matt.

Signed-off-by: Uma Shankar <uma.shankar@intel.com>
---
 drivers/gpu/drm/xe/display/intel_fbdev_fb.c   | 20 ++++++++++++++++++-
 drivers/gpu/drm/xe/display/xe_plane_initial.c | 12 +++++++++++
 drivers/gpu/drm/xe/xe_wa_oob.rules            |  1 +
 3 files changed, 32 insertions(+), 1 deletion(-)

Comments

Lucas De Marchi July 15, 2024, 1:22 p.m. UTC | #1
On Mon, Jul 15, 2024 at 02:26:59AM GMT, Uma Shankar wrote:
>As per recommendation in the workarounds:
>WA_22019338487
>
>There is an issue with accessing Stolen memory pages due a
>hardware limitation. Limit the usage of stolen memory for
>fbdev for LNL+. Don't use BIOS FB from stolen on LNL+ and
>assign the same from system memory.
>
>v2: Corrected the WA Number, limited WA to LNL and
>    Adopted XE_WA framework as suggested by Lucas and Matt.
>
>Signed-off-by: Uma Shankar <uma.shankar@intel.com>
>---
> drivers/gpu/drm/xe/display/intel_fbdev_fb.c   | 20 ++++++++++++++++++-
> drivers/gpu/drm/xe/display/xe_plane_initial.c | 12 +++++++++++
> drivers/gpu/drm/xe/xe_wa_oob.rules            |  1 +
> 3 files changed, 32 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
>index 816ad13821a8..9c70c9158108 100644
>--- a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
>+++ b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
>@@ -10,6 +10,8 @@
> #include "xe_bo.h"
> #include "xe_gt.h"
> #include "xe_ttm_stolen_mgr.h"
>+#include "xe_wa.h"

missing newline

>+#include <generated/xe_wa_oob.h>
>
> struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> 					       struct drm_fb_helper_surface_size *sizes)
>@@ -20,6 +22,9 @@ struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> 	struct drm_mode_fb_cmd2 mode_cmd = {};
> 	struct drm_i915_gem_object *obj;
> 	int size;
>+	bool wa_22019338487 = false;
>+	struct xe_gt *gt;
>+	u8 id;
>
> 	/* we don't do packed 24bpp */
> 	if (sizes->surface_bpp == 24)
>@@ -37,7 +42,19 @@ struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> 	size = PAGE_ALIGN(size);
> 	obj = ERR_PTR(-ENODEV);
>
>-	if (!IS_DGFX(xe)) {
>+	/*
>+	 * WA_22019338487:
>+	 * There is an issue with accessing Stolen memory pages
>+	 * due a hardware limitation. Limit the usage of stolen
>+	 * memory for fbdev for LNL+. Don't use BIOS FB from
>+	 * stolen on LNL+ and assign the same from system memory
>+	 */
>+	for_each_gt(gt, xe, id) {

why do you loop here, but in the other path you use main_gt of tile0?

I think at this point it's pretty safe to just do:

	if (XE_WA(xe_root_mmio_gt(xe), 22019338487))

Also, no need for the comment above, the commit message and WA
documentation is sufficient.

>+		if (XE_WA(gt, 22019338487))
>+			wa_22019338487 = true;
>+	}
>+
>+	if (!IS_DGFX(xe) && !wa_22019338487) {
> 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe),
> 					   NULL, size,
> 					   ttm_bo_type_kernel, XE_BO_FLAG_SCANOUT |
>@@ -48,6 +65,7 @@ struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> 		else
> 			drm_info(&xe->drm, "Allocated fbdev into stolen failed: %li\n", PTR_ERR(obj));
> 	}
>+
> 	if (IS_ERR(obj)) {
> 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL, size,
> 					   ttm_bo_type_kernel, XE_BO_FLAG_SCANOUT |
>diff --git a/drivers/gpu/drm/xe/display/xe_plane_initial.c b/drivers/gpu/drm/xe/display/xe_plane_initial.c
>index 5eccd6abb3ef..7e93ddad6df8 100644
>--- a/drivers/gpu/drm/xe/display/xe_plane_initial.c
>+++ b/drivers/gpu/drm/xe/display/xe_plane_initial.c
>@@ -18,6 +18,8 @@
> #include "intel_frontbuffer.h"
> #include "intel_plane_initial.h"
> #include "xe_bo.h"
>+#include "xe_wa.h"
>+#include <generated/xe_wa_oob.h>
>
> static bool
> intel_reuse_initial_plane_obj(struct intel_crtc *this,
>@@ -104,6 +106,16 @@ initial_plane_bo(struct xe_device *xe,
> 		phys_base = base;
> 		flags |= XE_BO_FLAG_STOLEN;
>
>+		/*
>+		 * WA_22019338487:
>+		 * There is an issue with accessing Stolen memory pages
>+		 * due a hardware limitation. Limit the usage of stolen
>+		 * memory for fbdev for LNL+. Don't use BIOS FB from
>+		 * stolen on LNL+ and assign the same from system memory
>+		 */
>+		if (XE_WA(tile0->primary_gt, 22019338487))

just use the same xe_root_mmio_gt() as suggested above.

>+			return NULL;
>+
> 		/*
> 		 * If the FB is too big, just don't use it since fbdev is not very
> 		 * important and we should probably use that space with FBC or other
>diff --git a/drivers/gpu/drm/xe/xe_wa_oob.rules b/drivers/gpu/drm/xe/xe_wa_oob.rules
>index 08f7336881e3..9b08fedbf85c 100644
>--- a/drivers/gpu/drm/xe/xe_wa_oob.rules
>+++ b/drivers/gpu/drm/xe/xe_wa_oob.rules
>@@ -29,4 +29,5 @@
> 13011645652	GRAPHICS_VERSION(2004)
> 22019338487	MEDIA_VERSION(2000)
> 		GRAPHICS_VERSION(2001)
>+		GRAPHICS_VERSION(2004)

This will end up matching the graphics GT in LNL for other paths it was
not previously taking. Looking at the code, main change will be:

drivers/gpu/drm/xe/xe_guc_pc.c:pc_max_freq_cap()
drivers/gpu/drm/xe/xe_gt.c:xe_gt_sanitize_freq()

about the freq handling for the GT. And the change will be wrong

I think we could just make this a new entry with:

	22019338487_display GRAPHICS_VERSION(2024)
or
	22019338487_display PLATFORM(LUNARLAKE)

I like the second more as then it doesn't matter what gt you use in the
code. Matt Roper, thoughts?

Lucas De Marchi

> 16023588340	GRAPHICS_VERSION(2001)
>-- 
>2.42.0
>
Shankar, Uma July 15, 2024, 6:47 p.m. UTC | #2
> -----Original Message-----
> From: De Marchi, Lucas <lucas.demarchi@intel.com>
> Sent: Monday, July 15, 2024 6:53 PM
> To: Shankar, Uma <uma.shankar@intel.com>
> Cc: intel-gfx@lists.freedesktop.org; intel-xe@lists.freedesktop.org;
> ville.syrjala@linux.intel.com; Ceraolo Spurio, Daniele
> <daniele.ceraolospurio@intel.com>; Belgaumkar, Vinay
> <vinay.belgaumkar@intel.com>; Roper, Matthew D
> <matthew.d.roper@intel.com>
> Subject: Re: [v2] drm/xe/fbdev: Limit the usage of stolen for LNL+
> 
> On Mon, Jul 15, 2024 at 02:26:59AM GMT, Uma Shankar wrote:
> >As per recommendation in the workarounds:
> >WA_22019338487
> >
> >There is an issue with accessing Stolen memory pages due a hardware
> >limitation. Limit the usage of stolen memory for fbdev for LNL+. Don't
> >use BIOS FB from stolen on LNL+ and assign the same from system memory.
> >
> >v2: Corrected the WA Number, limited WA to LNL and
> >    Adopted XE_WA framework as suggested by Lucas and Matt.
> >
> >Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> >---
> > drivers/gpu/drm/xe/display/intel_fbdev_fb.c   | 20 ++++++++++++++++++-
> > drivers/gpu/drm/xe/display/xe_plane_initial.c | 12 +++++++++++
> > drivers/gpu/drm/xe/xe_wa_oob.rules            |  1 +
> > 3 files changed, 32 insertions(+), 1 deletion(-)
> >
> >diff --git a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
> >b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
> >index 816ad13821a8..9c70c9158108 100644
> >--- a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
> >+++ b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
> >@@ -10,6 +10,8 @@
> > #include "xe_bo.h"
> > #include "xe_gt.h"
> > #include "xe_ttm_stolen_mgr.h"
> >+#include "xe_wa.h"
> 
> missing newline
> 
> >+#include <generated/xe_wa_oob.h>
> >
> > struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> > 					       struct drm_fb_helper_surface_size
> *sizes) @@ -20,6 +22,9
> >@@ struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper
> *helper,
> > 	struct drm_mode_fb_cmd2 mode_cmd = {};
> > 	struct drm_i915_gem_object *obj;
> > 	int size;
> >+	bool wa_22019338487 = false;
> >+	struct xe_gt *gt;
> >+	u8 id;
> >
> > 	/* we don't do packed 24bpp */
> > 	if (sizes->surface_bpp == 24)
> >@@ -37,7 +42,19 @@ struct intel_framebuffer *intel_fbdev_fb_alloc(struct
> drm_fb_helper *helper,
> > 	size = PAGE_ALIGN(size);
> > 	obj = ERR_PTR(-ENODEV);
> >
> >-	if (!IS_DGFX(xe)) {
> >+	/*
> >+	 * WA_22019338487:
> >+	 * There is an issue with accessing Stolen memory pages
> >+	 * due a hardware limitation. Limit the usage of stolen
> >+	 * memory for fbdev for LNL+. Don't use BIOS FB from
> >+	 * stolen on LNL+ and assign the same from system memory
> >+	 */
> >+	for_each_gt(gt, xe, id) {
> 
> why do you loop here, but in the other path you use main_gt of tile0?
> 
> I think at this point it's pretty safe to just do:
> 
> 	if (XE_WA(xe_root_mmio_gt(xe), 22019338487))

Yeah this sound a better choice here. Will drop the for loop and use this.
Thanks for pointing out.

> Also, no need for the comment above, the commit message and WA
> documentation is sufficient.

Sure, will do.
 
> >+		if (XE_WA(gt, 22019338487))
> >+			wa_22019338487 = true;
> >+	}
> >+
> >+	if (!IS_DGFX(xe) && !wa_22019338487) {
> > 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe),
> > 					   NULL, size,
> > 					   ttm_bo_type_kernel,
> XE_BO_FLAG_SCANOUT | @@ -48,6 +65,7 @@
> >struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
> > 		else
> > 			drm_info(&xe->drm, "Allocated fbdev into stolen failed:
> %li\n", PTR_ERR(obj));
> > 	}
> >+
> > 	if (IS_ERR(obj)) {
> > 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe),
> NULL, size,
> > 					   ttm_bo_type_kernel,
> XE_BO_FLAG_SCANOUT | diff --git
> >a/drivers/gpu/drm/xe/display/xe_plane_initial.c
> >b/drivers/gpu/drm/xe/display/xe_plane_initial.c
> >index 5eccd6abb3ef..7e93ddad6df8 100644
> >--- a/drivers/gpu/drm/xe/display/xe_plane_initial.c
> >+++ b/drivers/gpu/drm/xe/display/xe_plane_initial.c
> >@@ -18,6 +18,8 @@
> > #include "intel_frontbuffer.h"
> > #include "intel_plane_initial.h"
> > #include "xe_bo.h"
> >+#include "xe_wa.h"
> >+#include <generated/xe_wa_oob.h>
> >
> > static bool
> > intel_reuse_initial_plane_obj(struct intel_crtc *this, @@ -104,6
> >+106,16 @@ initial_plane_bo(struct xe_device *xe,
> > 		phys_base = base;
> > 		flags |= XE_BO_FLAG_STOLEN;
> >
> >+		/*
> >+		 * WA_22019338487:
> >+		 * There is an issue with accessing Stolen memory pages
> >+		 * due a hardware limitation. Limit the usage of stolen
> >+		 * memory for fbdev for LNL+. Don't use BIOS FB from
> >+		 * stolen on LNL+ and assign the same from system memory
> >+		 */
> >+		if (XE_WA(tile0->primary_gt, 22019338487))
> 
> just use the same xe_root_mmio_gt() as suggested above.
>
> >+			return NULL;
> >+
> > 		/*
> > 		 * If the FB is too big, just don't use it since fbdev is not very
> > 		 * important and we should probably use that space with FBC or
> other
> >diff --git a/drivers/gpu/drm/xe/xe_wa_oob.rules
> >b/drivers/gpu/drm/xe/xe_wa_oob.rules
> >index 08f7336881e3..9b08fedbf85c 100644
> >--- a/drivers/gpu/drm/xe/xe_wa_oob.rules
> >+++ b/drivers/gpu/drm/xe/xe_wa_oob.rules
> >@@ -29,4 +29,5 @@
> > 13011645652	GRAPHICS_VERSION(2004)
> > 22019338487	MEDIA_VERSION(2000)
> > 		GRAPHICS_VERSION(2001)
> >+		GRAPHICS_VERSION(2004)
> 
> This will end up matching the graphics GT in LNL for other paths it was not
> previously taking. Looking at the code, main change will be:
> 
> drivers/gpu/drm/xe/xe_guc_pc.c:pc_max_freq_cap()
> drivers/gpu/drm/xe/xe_gt.c:xe_gt_sanitize_freq()
> 
> about the freq handling for the GT. And the change will be wrong
> 
> I think we could just make this a new entry with:
> 
> 	22019338487_display GRAPHICS_VERSION(2024) or
> 	22019338487_display PLATFORM(LUNARLAKE)
> 
> I like the second more as then it doesn't matter what gt you use in the code. Matt
> Roper, thoughts?

Thanks Lucas, for pointing this out. Yes indeed it can cause that. I will adopt your 2nd option
and send a new version.

Thanks for all the valuable feedback and suggestions.

Regards,
Uma Shankar
 
> Lucas De Marchi
> 
> > 16023588340	GRAPHICS_VERSION(2001)
> >--
> >2.42.0
> >
diff mbox series

Patch

diff --git a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
index 816ad13821a8..9c70c9158108 100644
--- a/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
+++ b/drivers/gpu/drm/xe/display/intel_fbdev_fb.c
@@ -10,6 +10,8 @@ 
 #include "xe_bo.h"
 #include "xe_gt.h"
 #include "xe_ttm_stolen_mgr.h"
+#include "xe_wa.h"
+#include <generated/xe_wa_oob.h>
 
 struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
 					       struct drm_fb_helper_surface_size *sizes)
@@ -20,6 +22,9 @@  struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
 	struct drm_mode_fb_cmd2 mode_cmd = {};
 	struct drm_i915_gem_object *obj;
 	int size;
+	bool wa_22019338487 = false;
+	struct xe_gt *gt;
+	u8 id;
 
 	/* we don't do packed 24bpp */
 	if (sizes->surface_bpp == 24)
@@ -37,7 +42,19 @@  struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
 	size = PAGE_ALIGN(size);
 	obj = ERR_PTR(-ENODEV);
 
-	if (!IS_DGFX(xe)) {
+	/*
+	 * WA_22019338487:
+	 * There is an issue with accessing Stolen memory pages
+	 * due a hardware limitation. Limit the usage of stolen
+	 * memory for fbdev for LNL+. Don't use BIOS FB from
+	 * stolen on LNL+ and assign the same from system memory
+	 */
+	for_each_gt(gt, xe, id) {
+		if (XE_WA(gt, 22019338487))
+			wa_22019338487 = true;
+	}
+
+	if (!IS_DGFX(xe) && !wa_22019338487) {
 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe),
 					   NULL, size,
 					   ttm_bo_type_kernel, XE_BO_FLAG_SCANOUT |
@@ -48,6 +65,7 @@  struct intel_framebuffer *intel_fbdev_fb_alloc(struct drm_fb_helper *helper,
 		else
 			drm_info(&xe->drm, "Allocated fbdev into stolen failed: %li\n", PTR_ERR(obj));
 	}
+
 	if (IS_ERR(obj)) {
 		obj = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL, size,
 					   ttm_bo_type_kernel, XE_BO_FLAG_SCANOUT |
diff --git a/drivers/gpu/drm/xe/display/xe_plane_initial.c b/drivers/gpu/drm/xe/display/xe_plane_initial.c
index 5eccd6abb3ef..7e93ddad6df8 100644
--- a/drivers/gpu/drm/xe/display/xe_plane_initial.c
+++ b/drivers/gpu/drm/xe/display/xe_plane_initial.c
@@ -18,6 +18,8 @@ 
 #include "intel_frontbuffer.h"
 #include "intel_plane_initial.h"
 #include "xe_bo.h"
+#include "xe_wa.h"
+#include <generated/xe_wa_oob.h>
 
 static bool
 intel_reuse_initial_plane_obj(struct intel_crtc *this,
@@ -104,6 +106,16 @@  initial_plane_bo(struct xe_device *xe,
 		phys_base = base;
 		flags |= XE_BO_FLAG_STOLEN;
 
+		/*
+		 * WA_22019338487:
+		 * There is an issue with accessing Stolen memory pages
+		 * due a hardware limitation. Limit the usage of stolen
+		 * memory for fbdev for LNL+. Don't use BIOS FB from
+		 * stolen on LNL+ and assign the same from system memory
+		 */
+		if (XE_WA(tile0->primary_gt, 22019338487))
+			return NULL;
+
 		/*
 		 * If the FB is too big, just don't use it since fbdev is not very
 		 * important and we should probably use that space with FBC or other
diff --git a/drivers/gpu/drm/xe/xe_wa_oob.rules b/drivers/gpu/drm/xe/xe_wa_oob.rules
index 08f7336881e3..9b08fedbf85c 100644
--- a/drivers/gpu/drm/xe/xe_wa_oob.rules
+++ b/drivers/gpu/drm/xe/xe_wa_oob.rules
@@ -29,4 +29,5 @@ 
 13011645652	GRAPHICS_VERSION(2004)
 22019338487	MEDIA_VERSION(2000)
 		GRAPHICS_VERSION(2001)
+		GRAPHICS_VERSION(2004)
 16023588340	GRAPHICS_VERSION(2001)