Commit 75fb60e5 authored by Jocelyn Falempe's avatar Jocelyn Falempe Committed by Maarten Lankhorst
Browse files

drm/i915: Add intel_bo_panic_setup() and intel_bo_panic_finish() 



Implement both functions for i915 and xe, they prepare the work for
drm_panic support.
They both use kmap_try_from_panic(), and map one page at a time, to
write the panic screen on the framebuffer.

Signed-off-by: default avatarJocelyn Falempe <jfalempe@redhat.com>
Link: https://lore.kernel.org/r/20250624091501.257661-8-jfalempe@redhat.com


Signed-off-by: default avatarMaarten Lankhorst <dev@lankhorst.se>
parent da091afa

drivers/gpu/drm/i915/display/intel_bo.c

+11 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: MIT

/* Copyright © 2024 Intel Corporation */



#include <drm/drm_panic.h>

#include "display/intel_display_types.h"

#include "gem/i915_gem_mman.h"

#include "gem/i915_gem_object.h"
@@ -63,3 +64,13 @@ struct intel_framebuffer *intel_bo_alloc_framebuffer(void) 
{

	return i915_gem_object_alloc_framebuffer();

}



int intel_bo_panic_setup(struct drm_scanout_buffer *sb)

{

	return i915_gem_object_panic_setup(sb);

}



void intel_bo_panic_finish(struct intel_framebuffer *fb)

{

	return i915_gem_object_panic_finish(fb);

}

drivers/gpu/drm/i915/display/intel_bo.h

+3 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#include <linux/types.h>



struct drm_gem_object;

struct drm_scanout_buffer;

struct intel_framebuffer;

struct seq_file;

struct vm_area_struct;
@@ -25,5 +26,7 @@ struct intel_frontbuffer *intel_bo_set_frontbuffer(struct drm_gem_object *obj, 


void intel_bo_describe(struct seq_file *m, struct drm_gem_object *obj);

struct intel_framebuffer *intel_bo_alloc_framebuffer(void);

int intel_bo_panic_setup(struct drm_scanout_buffer *sb);

void intel_bo_panic_finish(struct intel_framebuffer *fb);



#endif /* __INTEL_BO__ */

drivers/gpu/drm/i915/gem/i915_gem_object.h

+4 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include "i915_gem_ww.h"

#include "i915_vma_types.h"



struct drm_scanout_buffer;

enum intel_region_id;

struct intel_framebuffer;
@@ -693,6 +694,9 @@ int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj); 
int i915_gem_object_truncate(struct drm_i915_gem_object *obj);



struct intel_framebuffer *i915_gem_object_alloc_framebuffer(void);

int i915_gem_object_panic_setup(struct drm_scanout_buffer *sb);

void i915_gem_object_panic_finish(struct intel_framebuffer *fb);



/**

 * i915_gem_object_pin_map - return a contiguous mapping of the entire object

 * @obj: the object to map into kernel address space

drivers/gpu/drm/i915/gem/i915_gem_pages.c

+106 −0
Original line number Diff line number Diff line
@@ -4,8 +4,10 @@ 
 */



#include <drm/drm_cache.h>

#include <drm/drm_panic.h>

#include <linux/vmalloc.h>



#include "display/intel_fb.h"

#include "display/intel_display_types.h"

#include "gt/intel_gt.h"

#include "gt/intel_tlb.h"
@@ -366,6 +368,67 @@ struct i915_framebuffer { 
	struct i915_panic_data panic;

};



static inline struct i915_panic_data *to_i915_panic_data(struct intel_framebuffer *fb)

{

	return &container_of_const(fb, struct i915_framebuffer, base)->panic;

}



static void i915_panic_kunmap(struct i915_panic_data *panic)

{

	if (panic->vaddr) {

		drm_clflush_virt_range(panic->vaddr, PAGE_SIZE);

		kunmap_local(panic->vaddr);

		panic->vaddr = NULL;

	}

}



static struct page **i915_gem_object_panic_pages(struct drm_i915_gem_object *obj)

{

	unsigned long n_pages = obj->base.size >> PAGE_SHIFT, i;

	struct page *page;

	struct page **pages;

	struct sgt_iter iter;



	/* For a 3840x2160 32 bits Framebuffer, this should require ~64K */

	pages = kmalloc_array(n_pages, sizeof(*pages), GFP_ATOMIC);

	if (!pages)

		return NULL;



	i = 0;

	for_each_sgt_page(page, iter, obj->mm.pages)

		pages[i++] = page;

	return pages;

}



/*

 * The scanout buffer pages are not mapped, so for each pixel,

 * use kmap_local_page_try_from_panic() to map the page, and write the pixel.

 * Try to keep the map from the previous pixel, to avoid too much map/unmap.

 */

static void i915_gem_object_panic_page_set_pixel(struct drm_scanout_buffer *sb, unsigned int x,

						 unsigned int y, u32 color)

{

	unsigned int new_page;

	unsigned int offset;

	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;

	struct i915_panic_data *panic = to_i915_panic_data(fb);



	offset = y * sb->pitch[0] + x * sb->format->cpp[0];



	new_page = offset >> PAGE_SHIFT;

	offset = offset % PAGE_SIZE;

	if (new_page != panic->page) {

		i915_panic_kunmap(panic);

		panic->page = new_page;

		panic->vaddr =

			kmap_local_page_try_from_panic(panic->pages[panic->page]);

	}

	if (panic->vaddr) {

		u32 *pix = panic->vaddr + offset;

		*pix = color;

	}

}



struct intel_framebuffer *i915_gem_object_alloc_framebuffer(void)

{

	struct i915_framebuffer *i915_fb;
@@ -376,6 +439,49 @@ struct intel_framebuffer *i915_gem_object_alloc_framebuffer(void) 
	return NULL;

}



/*

 * Setup the gem framebuffer for drm_panic access.

 * Use current vaddr if it exists, or setup a list of pages.

 * pfn is not supported yet.

 */

int i915_gem_object_panic_setup(struct drm_scanout_buffer *sb)

{

	enum i915_map_type has_type;

	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;

	struct i915_panic_data *panic = to_i915_panic_data(fb);

	struct drm_i915_gem_object *obj = to_intel_bo(intel_fb_bo(&fb->base));

	void *ptr;



	ptr = page_unpack_bits(obj->mm.mapping, &has_type);

	if (ptr) {

		if (i915_gem_object_has_iomem(obj))

			iosys_map_set_vaddr_iomem(&sb->map[0], (void __iomem *)ptr);

		else

			iosys_map_set_vaddr(&sb->map[0], ptr);



		return 0;

	}

	if (i915_gem_object_has_struct_page(obj)) {

		panic->pages = i915_gem_object_panic_pages(obj);

		if (!panic->pages)

			return -ENOMEM;

		panic->page = -1;

		sb->set_pixel = i915_gem_object_panic_page_set_pixel;

		return 0;

	}

	return -EOPNOTSUPP;

}



void i915_gem_object_panic_finish(struct intel_framebuffer *fb)

{

	struct i915_panic_data *panic = to_i915_panic_data(fb);



	i915_panic_kunmap(panic);

	panic->page = -1;

	kfree(panic->pages);

	panic->pages = NULL;

}



/* get, pin, and map the pages of the object into kernel space */

void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj,

			      enum i915_map_type type)

drivers/gpu/drm/xe/display/intel_bo.c

+64 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: MIT

/* Copyright © 2024 Intel Corporation */



#include <drm/drm_cache.h>

#include <drm/drm_gem.h>

#include <drm/drm_panic.h>



#include "intel_fb.h"

#include "intel_display_types.h"



#include "xe_bo.h"
@@ -73,6 +76,50 @@ struct xe_framebuffer { 
	struct xe_panic_data panic;

};



static inline struct xe_panic_data *to_xe_panic_data(struct intel_framebuffer *fb)

{

	return &container_of_const(fb, struct xe_framebuffer, base)->panic;

}



static void xe_panic_kunmap(struct xe_panic_data *panic)

{

	if (panic->vaddr) {

		drm_clflush_virt_range(panic->vaddr, PAGE_SIZE);

		kunmap_local(panic->vaddr);

		panic->vaddr = NULL;

	}

}



/*

 * The scanout buffer pages are not mapped, so for each pixel,

 * use kmap_local_page_try_from_panic() to map the page, and write the pixel.

 * Try to keep the map from the previous pixel, to avoid too much map/unmap.

 */

static void xe_panic_page_set_pixel(struct drm_scanout_buffer *sb, unsigned int x,

				    unsigned int y, u32 color)

{

	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;

	struct xe_panic_data *panic = to_xe_panic_data(fb);

	struct xe_bo *bo = gem_to_xe_bo(intel_fb_bo(&fb->base));

	unsigned int new_page;

	unsigned int offset;



	offset = y * sb->pitch[0] + x * sb->format->cpp[0];



	new_page = offset >> PAGE_SHIFT;

	offset = offset % PAGE_SIZE;

	if (new_page != panic->page) {

		xe_panic_kunmap(panic);

		panic->page = new_page;

		panic->vaddr = ttm_bo_kmap_try_from_panic(&bo->ttm,

							  panic->page);

	}

	if (panic->vaddr) {

		u32 *pix = panic->vaddr + offset;

		*pix = color;

	}

}



struct intel_framebuffer *intel_bo_alloc_framebuffer(void)

{

	struct xe_framebuffer *xe_fb;
@@ -83,3 +130,20 @@ struct intel_framebuffer *intel_bo_alloc_framebuffer(void) 
	return NULL;

}



int intel_bo_panic_setup(struct drm_scanout_buffer *sb)

{

	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;

	struct xe_panic_data *panic = to_xe_panic_data(fb);



	panic->page = -1;

	sb->set_pixel = xe_panic_page_set_pixel;

	return 0;

}



void intel_bo_panic_finish(struct intel_framebuffer *fb)

{

	struct xe_panic_data *panic = to_xe_panic_data(fb);



	xe_panic_kunmap(panic);

	panic->page = -1;

}