On 18/10/2024 23:50, Lyude Paul wrote:
On Fri, 2024-09-13 at 09:03 +0200, Jocelyn Falempe wrote:
Add drm_panic support, for nv50+ cards.
It's enough to get the panic screen while running Gnome/Wayland on a
GTX 1650.
It doesn't support multi-plane or compressed format.
Support for other formats and older cards will come later.
Tiling is only tested on GTX1650, and might be wrong for other cards.
Signed-off-by: Jocelyn Falempe <jfale...@redhat.com>
---
v2:
* Rebase and drop already merged patches.
* Rework the tiling algorithm, using "swizzle" to compute the offset
inside the block.
v3:
* Fix support for Tesla GPU, which have simpler tiling.
* Use nouveau_framebuffer_get_layout() to get the tiling parameters.
* Have 2 set_pixel() functions, depending on GPU family.
drivers/gpu/drm/nouveau/dispnv50/wndw.c | 139 +++++++++++++++++++++++-
1 file changed, 137 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/dispnv50/wndw.c
b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
index 7a2cceaee6e9..419c5f359711 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/wndw.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
@@ -30,11 +30,16 @@
#include <nvhw/class/cl507e.h>
#include <nvhw/class/clc37e.h>
+#include <linux/iosys-map.h>
+
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_blend.h>
-#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_panic.h>
+#include <drm/ttm/ttm_bo.h>
#include "nouveau_bo.h"
#include "nouveau_gem.h"
@@ -577,6 +582,125 @@ nv50_wndw_prepare_fb(struct drm_plane *plane, struct
drm_plane_state *state)
return 0;
}
+#define NV_TILE_BLK_BASE_HEIGHT_TESLA 4 /* In pixel */
+#define NV_TILE_BLK_BASE_HEIGHT 8 /* In pixel */
+#define NV_TILE_GOB_SIZE 64 /* In bytes */
+#define NV_TILE_BLK_WIDTH (NV_TILE_GOB_SIZE / 4) /* For 32 bits pixel */
This was a bit confusing to look at so I had to go and review how some of this
works. I think it might be better to name this something like:
NV_TILE_GOB_WIDTH_BYTES
Since -technically- the size of a gob is much larger (from nouveau_display.c):
if (drm->client.device.info.family < NV_DEVICE_INFO_V0_FERMI)
gob_size = 256;
else
gob_size = 512;
It's just you're only concerned about the width here.
Ah thanks, actually I wasn't sure why my gob size was different.
The corresponding define in nouveau_display.c is
https://elixir.bootlin.com/linux/v6.11.4/source/drivers/gpu/drm/nouveau/nouveau_display.c#L229
+
+/* Only used by drm_panic get_scanout_buffer() and set_pixel(), so it is
+ * protected by the drm panic spinlock
+ */
+static u32 nv50_panic_blk_h;
+
+/* Return the framebuffer offset of the start of the block where pixel(x,y) is
*/
+static u32
+nv50_get_block_off(unsigned int x, unsigned int y, unsigned int width)
+{
+ u32 blk_x, blk_y, blk_columns;
+
+ blk_columns = DIV_ROUND_UP(width, NV_TILE_BLK_WIDTH);
+ blk_x = x / NV_TILE_BLK_WIDTH;
+ blk_y = y / nv50_panic_blk_h;
+
+ return ((blk_y * blk_columns) + blk_x) * NV_TILE_GOB_SIZE *
nv50_panic_blk_h;
+}
+
+/* Turing and later have 2 level of tiles inside the block */
+static void
+nv50_set_pixel_swizzle(struct drm_scanout_buffer *sb, unsigned int x,
+ unsigned int y, u32 color)
+{
+ u32 blk_off, off, swizzle;
+
+ blk_off = nv50_get_block_off(x, y, sb->width);
+
+ y = y % nv50_panic_blk_h;
+
+ /* Inside the block, use the fast address swizzle to compute the offset
+ * For nvidia blocklinear, bit order is yn..y3 x3 y2 x2 y1 y0 x1 x0
+ */
+ swizzle = (x & 3) | (y & 3) << 2 | (x & 4) << 2 | (y & 4) << 3;
+ swizzle |= (x & 8) << 3 | (y >> 3) << 7;
+ off = blk_off + swizzle * 4;
+
+ iosys_map_wr(&sb->map[0], off, u32, color);
+}
+
+static void
+nv50_set_pixel(struct drm_scanout_buffer *sb, unsigned int x, unsigned int y,
+ u32 color)
+{
+ u32 blk_off, off;
+
+ blk_off = nv50_get_block_off(x, y, sb->width);
+
+ x = x % NV_TILE_BLK_WIDTH;
+ y = y % nv50_panic_blk_h;
+ off = blk_off + (x + y * NV_TILE_BLK_WIDTH) * 4;
+
+ iosys_map_wr(&sb->map[0], off, u32, color);
+}
+
+static u32
+nv50_get_block_height(u32 tile_mode, u16 chipset)
+{
+ if (chipset < 0xc0)
+ return NV_TILE_BLK_BASE_HEIGHT_TESLA * (1 << tile_mode);
+ else
+ return NV_TILE_BLK_BASE_HEIGHT * (1 << (tile_mode >> 4));
I see this is mentioned above around the definition of NV_TILE_BLK_BASE* - but
we might want to leave a comment (or rename it) to make it more clear that
this returns a size in pixels. Since we already have some functions in
nouveau_display.c regarding similar but different calculations (like
nouveau_get_height_in_blocks()).
Sure, I will add a comment here.
I was also going to ask if you might be able to reuse some of those functions
- or have nouveau_display.c reuse some of your code where we verify
framebuffer sizes. Mainly since we have some functions already for calculating
width/height of a framebuffer in blocks. But I'm having a bit of trouble
figuring out if that's possible/relevant, so I'll leave that to you to decide.
Yes, there are some duplicates between the two, and I can't reuse
directly the functions from nouveau_display.c, because they don't fit
what I need here.
If I try to share some code, is it ok to create a dispnv50/tile.[ch] ?
or is there a better place ?
+}
+
+static int
+nv50_wndw_get_scanout_buffer(struct drm_plane *plane, struct
drm_scanout_buffer *sb)
+{
+ struct drm_framebuffer *fb;
+ struct nouveau_bo *nvbo;
+ struct nouveau_drm *drm = nouveau_drm(plane->dev);
+ u16 chipset = drm->client.device.info.chipset;
+ u32 tile_mode;
+ u8 kind;
+
+ if (!plane->state || !plane->state->fb)
+ return -EINVAL;
+
+ fb = plane->state->fb;
+ nvbo = nouveau_gem_object(fb->obj[0]);
+
+ /* Don't support compressed format, or multiplane yet. */
+ if (nvbo->comp || fb->format->num_planes != 1)
+ return -EOPNOTSUPP;
+
+ if (nouveau_bo_map(nvbo)) {
+ pr_warn("nouveau bo map failed, panic won't be displayed\n");
I think we would want drm_warn() here
sure I will change that.
With the above changes handled/considered -
Reviewed-by: Lyude Paul <ly...@redhat.com>
Thanks a lot, I will send a v4 later this week.
Would be good to have james take another look at this if he's got the time,
but I think this looks alright :)
+ return -ENOMEM;
+ }
+
+ if (nvbo->kmap.bo_kmap_type & TTM_BO_MAP_IOMEM_MASK)
+ iosys_map_set_vaddr_iomem(&sb->map[0], (void __iomem *)
nvbo->kmap.virtual);
+ else
+ iosys_map_set_vaddr(&sb->map[0], nvbo->kmap.virtual);
+
+ sb->height = fb->height;
+ sb->width = fb->width;
+ sb->pitch[0] = fb->pitches[0];
+ sb->format = fb->format;
+
+ nouveau_framebuffer_get_layout(fb, &tile_mode, &kind);
+ if (kind) {
+ /* If tiling is enabled, use set_pixel() to display correctly.
+ * Only handle 32bits format for now.
+ */
+ if (fb->format->cpp[0] != 4)
+ return -EOPNOTSUPP;
+ nv50_panic_blk_h = nv50_get_block_height(tile_mode, chipset);
+ if (chipset >= 0x160)
+ sb->set_pixel = nv50_set_pixel_swizzle;
+ else
+ sb->set_pixel = nv50_set_pixel;
+ }
+ return 0;
+}
+
static const struct drm_plane_helper_funcs
nv50_wndw_helper = {
.prepare_fb = nv50_wndw_prepare_fb,
@@ -584,6 +708,14 @@ nv50_wndw_helper = {
.atomic_check = nv50_wndw_atomic_check,
};
+static const struct drm_plane_helper_funcs
+nv50_wndw_primary_helper = {
+ .prepare_fb = nv50_wndw_prepare_fb,
+ .cleanup_fb = nv50_wndw_cleanup_fb,
+ .atomic_check = nv50_wndw_atomic_check,
+ .get_scanout_buffer = nv50_wndw_get_scanout_buffer,
+};
+
static void
nv50_wndw_atomic_destroy_state(struct drm_plane *plane,
struct drm_plane_state *state)
@@ -732,7 +864,10 @@ nv50_wndw_new_(const struct nv50_wndw_func *func, struct
drm_device *dev,
return ret;
}
- drm_plane_helper_add(&wndw->plane, &nv50_wndw_helper);
+ if (type == DRM_PLANE_TYPE_PRIMARY)
+ drm_plane_helper_add(&wndw->plane, &nv50_wndw_primary_helper);
+ else
+ drm_plane_helper_add(&wndw->plane, &nv50_wndw_helper);
if (wndw->func->ilut) {
ret = nv50_lut_init(disp, mmu, &wndw->ilut);
