kdb, kms: Save and restore the LUT on atomic KMS enter/exit

When changing VTs non-atomically the kernel works in conjunction with
the Xserver in user space and receives the LUT information from the
Xserver via a system call.  When changing modes atomically for kdb,
this information must be saved and restored without disturbing user
space as if nothing ever happened.

There is a short cut used by this patch where gamma_store is used as
the save space.  If this turns out to be a problem in the future a
pre-allocated chunk of memory will be required for each crtc to save
and restore the LUT information.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: David Airlie <airlied@linux.ie>
CC: dri-devel@lists.freedesktop.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Jason Wessel 2010-10-13 14:09:43 -05:00 committed by Dave Airlie
parent 38ed0fcacd
commit 99231028ff
1 changed files with 26 additions and 0 deletions

View File

@ -242,6 +242,30 @@ static int drm_fb_helper_parse_command_line(struct drm_fb_helper *fb_helper)
return 0;
}
static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
{
uint16_t *r_base, *g_base, *b_base;
int i;
r_base = crtc->gamma_store;
g_base = r_base + crtc->gamma_size;
b_base = g_base + crtc->gamma_size;
for (i = 0; i < crtc->gamma_size; i++)
helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
}
static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
{
uint16_t *r_base, *g_base, *b_base;
r_base = crtc->gamma_store;
g_base = r_base + crtc->gamma_size;
b_base = g_base + crtc->gamma_size;
crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
}
int drm_fb_helper_debug_enter(struct fb_info *info)
{
struct drm_fb_helper *helper = info->par;
@ -260,6 +284,7 @@ int drm_fb_helper_debug_enter(struct fb_info *info)
continue;
funcs = mode_set->crtc->helper_private;
drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
funcs->mode_set_base_atomic(mode_set->crtc,
mode_set->fb,
mode_set->x,
@ -309,6 +334,7 @@ int drm_fb_helper_debug_leave(struct fb_info *info)
continue;
}
drm_fb_helper_restore_lut_atomic(mode_set->crtc);
funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
crtc->y, 0);
}