On Wed, 26 Aug 2020 at 02:52, Lyude Paul lyude@redhat.com wrote:
On Tue, 2020-08-25 at 08:28 +1000, Ben Skeggs wrote:
On Tue, 25 Aug 2020 at 04:33, Lyude Paul lyude@redhat.com wrote:
Not entirely sure why this never came up when I originally tested this (maybe some BIOSes already have this setup?) but the ->caps_init vfunc appears to cause the display engine to throw an exception on driver init, at least on my ThinkPad P72:
nouveau 0000:01:00.0: disp: chid 0 mthd 008c data 00000000 0000508c 0000102b
This is magic nvidia speak for "You need to have the DMA notifier offset programmed before you can call NV507D_GET_CAPABILITIES." So, let's fix this by doing that, and also perform an update afterwards to prevent racing with the GPU when reading capabilities.
Changes since v1:
- Don't just program the DMA notifier offset, make sure to actually perform an update
I'm not sure there's a need to send an Update() method here, I believe GetCapabilities() is an action method on its own right?
I'm not entirely sure about this part tbh. I do know that we need to call GetCapabilities() _after_ the DMA notifier offset is programmed. But, my assumption was that if GetCapabilities() requires a DMA notifier offset to store its results in, we'd probably want to fire an update or something to make sure that we're not reading before it finishes writing capabilities?
We definitely want to *wait* on GetCapabilities() finishing, I believe it should also update the notifier the same (or similar) way Update() does. But I don't think we want to send an Update() here, it'll actually trigger a modeset (which, on earlier HW, will tear down the boot mode. Not sure about current HW, it might preserve state), and we may not want that to happen there.
Ben.
Ben.
Signed-off-by: Lyude Paul lyude@redhat.com Fixes: 4a2cb4181b07 ("drm/nouveau/kms/nv50-: Probe SOR and PIOR caps for DP interlacing support") Cc: stable@vger.kernel.org # v5.8+
drivers/gpu/drm/nouveau/dispnv50/core507d.c | 25 ++++++++++++++++----- 1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/dispnv50/core507d.c b/drivers/gpu/drm/nouveau/dispnv50/core507d.c index e341f572c2696..5e86feec3b720 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/core507d.c +++ b/drivers/gpu/drm/nouveau/dispnv50/core507d.c @@ -65,13 +65,26 @@ core507d_ntfy_init(struct nouveau_bo *bo, u32 offset) int core507d_caps_init(struct nouveau_drm *drm, struct nv50_disp *disp) {
u32 *push = evo_wait(&disp->core->chan, 2);
struct nv50_core *core = disp->core;u32 interlock[NV50_DISP_INTERLOCK__SIZE] = {0};u32 *push;
if (push) {evo_mthd(push, 0x008c, 1);evo_data(push, 0x0);evo_kick(push, &disp->core->chan);}
core->func->ntfy_init(disp->sync, NV50_DISP_CORE_NTFY);push = evo_wait(&core->chan, 4);if (!push)return 0;evo_mthd(push, 0x0084, 1);evo_data(push, 0x80000000 | NV50_DISP_CORE_NTFY);evo_mthd(push, 0x008c, 1);evo_data(push, 0x0);evo_kick(push, &core->chan);core->func->update(core, interlock, false);if (core->func->ntfy_wait_done(disp->sync, NV50_DISP_CORE_NTFY,core->chan.base.device))NV_ERROR(drm, "core notifier timeout\n"); return 0;}
2.26.2
Nouveau mailing list Nouveau@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/nouveau
-- Sincerely, Lyude Paul (she/her) Software Engineer at Red Hat