xe_panic.c

  1// SPDX-License-Identifier: MIT
  2/* Copyright © 2025 Intel Corporation */
  3
  4#include <drm/drm_cache.h>
  5#include <drm/drm_panic.h>
  6
  7#include "intel_display_types.h"
  8#include "intel_fb.h"
  9#include "intel_panic.h"
 10#include "xe_bo.h"
 11#include "xe_res_cursor.h"
 12
 13struct intel_panic {
 14	struct xe_res_cursor res;
 15	struct iosys_map vmap;
 16
 17	int page;
 18};
 19
 20static void xe_panic_kunmap(struct intel_panic *panic)
 21{
 22	if (!panic->vmap.is_iomem && iosys_map_is_set(&panic->vmap)) {
 23		drm_clflush_virt_range(panic->vmap.vaddr, PAGE_SIZE);
 24		kunmap_local(panic->vmap.vaddr);
 25	}
 26	iosys_map_clear(&panic->vmap);
 27	panic->page = -1;
 28}
 29
 30/*
 31 * The scanout buffer pages are not mapped, so for each pixel,
 32 * use kmap_local_page_try_from_panic() to map the page, and write the pixel.
 33 * Try to keep the map from the previous pixel, to avoid too much map/unmap.
 34 */
 35static void xe_panic_page_set_pixel(struct drm_scanout_buffer *sb, unsigned int x,
 36				    unsigned int y, u32 color)
 37{
 38	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;
 39	struct intel_panic *panic = fb->panic;
 40	struct xe_bo *bo = gem_to_xe_bo(intel_fb_bo(&fb->base));
 41	unsigned int new_page;
 42	unsigned int offset;
 43
 44	if (fb->panic_tiling)
 45		offset = fb->panic_tiling(sb->width, x, y);
 46	else
 47		offset = y * sb->pitch[0] + x * sb->format->cpp[0];
 48
 49	new_page = offset >> PAGE_SHIFT;
 50	offset = offset % PAGE_SIZE;
 51	if (new_page != panic->page) {
 52		if (xe_bo_is_vram(bo)) {
 53			/* Display is always mapped on root tile */
 54			struct xe_vram_region *vram = xe_bo_device(bo)->mem.vram;
 55
 56			if (panic->page < 0 || new_page < panic->page) {
 57				xe_res_first(bo->ttm.resource, new_page * PAGE_SIZE,
 58					     bo->ttm.base.size - new_page * PAGE_SIZE, &panic->res);
 59			} else {
 60				xe_res_next(&panic->res, PAGE_SIZE * (new_page - panic->page));
 61			}
 62			iosys_map_set_vaddr_iomem(&panic->vmap,
 63						  vram->mapping + panic->res.start);
 64		} else {
 65			xe_panic_kunmap(panic);
 66			iosys_map_set_vaddr(&panic->vmap,
 67					    ttm_bo_kmap_try_from_panic(&bo->ttm,
 68								       new_page));
 69		}
 70		panic->page = new_page;
 71	}
 72
 73	if (iosys_map_is_set(&panic->vmap))
 74		iosys_map_wr(&panic->vmap, offset, u32, color);
 75}
 76
 77struct intel_panic *intel_panic_alloc(void)
 78{
 79	struct intel_panic *panic;
 80
 81	panic = kzalloc(sizeof(*panic), GFP_KERNEL);
 82
 83	return panic;
 84}
 85
 86int intel_panic_setup(struct intel_panic *panic, struct drm_scanout_buffer *sb)
 87{
 88	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;
 89	struct xe_bo *bo = gem_to_xe_bo(intel_fb_bo(&fb->base));
 90
 91	if (xe_bo_is_vram(bo) && !xe_bo_is_visible_vram(bo))
 92		return -ENODEV;
 93
 94	panic->page = -1;
 95	sb->set_pixel = xe_panic_page_set_pixel;
 96	return 0;
 97}
 98
 99void intel_panic_finish(struct intel_panic *panic)
100{
101	xe_panic_kunmap(panic);
102}