On Wed, 2010-11-10 at 16:32 -0500, Andy Lutomirski wrote:
> The old code generated an interrupt storm bad enough to completely
> take down my system.
>
> This only fixes the bits that are defined nouveau_regs.h. Newer hardware
> uses another register that isn't described, and I don't have that hardware
> to test.
Thanks for looking at this. I'll take a closer look at the problem
today and see what I can come up with too, that'll work with the newer
hardware too.
Ben.
>
> Signed-off-by: Andy Lutomirski <luto at mit.edu>
> Cc: <stable at kernel.org>
> ---
> drivers/gpu/drm/nouveau/nouveau_drv.h | 5 +++++
> drivers/gpu/drm/nouveau/nouveau_irq.c | 1 +
> drivers/gpu/drm/nouveau/nv50_display.c | 17 +++++++++++++----
> 3 files changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h
> b/drivers/gpu/drm/nouveau/nouveau_drv.h
> index b1be617..b6c62cc 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_drv.h
> +++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
> @@ -531,6 +531,11 @@ struct drm_nouveau_private {
> struct work_struct irq_work;
> struct work_struct hpd_work;
>
> + struct {
> + spinlock_t lock;
> + uint32_t hpd0_bits;
> + } hpd_state;
> +
> struct list_head vbl_waiting;
>
> struct {
> diff --git a/drivers/gpu/drm/nouveau/nouveau_irq.c
> b/drivers/gpu/drm/nouveau/nouveau_irq.c
> index 794b0ee..b62a601 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_irq.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_irq.c
> @@ -52,6 +52,7 @@ nouveau_irq_preinstall(struct drm_device *dev)
> if (dev_priv->card_type >= NV_50) {
> INIT_WORK(&dev_priv->irq_work, nv50_display_irq_handler_bh);
> INIT_WORK(&dev_priv->hpd_work, nv50_display_irq_hotplug_bh);
> + spin_lock_init(&dev_priv->hpd_state.lock);
> INIT_LIST_HEAD(&dev_priv->vbl_waiting);
> }
> }
> diff --git a/drivers/gpu/drm/nouveau/nv50_display.c
> b/drivers/gpu/drm/nouveau/nv50_display.c
> index 83a7d27..0df08e3 100644
> --- a/drivers/gpu/drm/nouveau/nv50_display.c
> +++ b/drivers/gpu/drm/nouveau/nv50_display.c
> @@ -1014,7 +1014,12 @@ nv50_display_irq_hotplug_bh(struct work_struct *work)
> uint32_t unplug_mask, plug_mask, change_mask;
> uint32_t hpd0, hpd1 = 0;
>
> - hpd0 = nv_rd32(dev, NV50_PCONNECTOR_HOTPLUG_CTRL) & nv_rd32(dev,
> NV50_PCONNECTOR_HOTPLUG_INTR);
> + spin_lock_irq(&dev_priv->hpd_state.lock);
> + hpd0 = dev_priv->hpd_state.hpd0_bits;
> + dev_priv->hpd_state.hpd0_bits = 0;
> + spin_unlock_irq(&dev_priv->hpd_state.lock);
> +
> + hpd0 &= nv_rd32(dev, NV50_PCONNECTOR_HOTPLUG_INTR);
> if (dev_priv->chipset >= 0x90)
> hpd1 = nv_rd32(dev, 0xe074) & nv_rd32(dev, 0xe070);
>
> @@ -1058,7 +1063,6 @@ nv50_display_irq_hotplug_bh(struct work_struct *work)
> helper->dpms(connector->encoder, DRM_MODE_DPMS_OFF);
> }
>
> - nv_wr32(dev, NV50_PCONNECTOR_HOTPLUG_CTRL, nv_rd32(dev,
> NV50_PCONNECTOR_HOTPLUG_CTRL));
> if (dev_priv->chipset >= 0x90)
> nv_wr32(dev, 0xe074, nv_rd32(dev, 0xe074));
>
> @@ -1072,8 +1076,13 @@ nv50_display_irq_handler(struct drm_device *dev)
> uint32_t delayed = 0;
>
> if (nv_rd32(dev, NV50_PMC_INTR_0) & NV50_PMC_INTR_0_HOTPLUG) {
> - if (!work_pending(&dev_priv->hpd_work))
> - queue_work(dev_priv->wq, &dev_priv->hpd_work);
> + uint32_t hpd0_bits = nv_rd32(dev, NV50_PCONNECTOR_HOTPLUG_CTRL);
> + nv_wr32(dev, NV50_PCONNECTOR_HOTPLUG_CTRL, hpd0_bits);
> + spin_lock(&dev_priv->hpd_state.lock);
> + dev_priv->hpd_state.hpd0_bits |= hpd0_bits;
> + spin_unlock(&dev_priv->hpd_state.lock);
> +
> + queue_work(dev_priv->wq, &dev_priv->hpd_work);
> }
>
> while (nv_rd32(dev, NV50_PMC_INTR_0) & NV50_PMC_INTR_0_DISPLAY) {
