drm/nouveau/pbus: add a PBUS subdev that hands IRQs to the right subdevs

We are going to use PTHERM's IRQs for thermal monitoring but we need to route
them first.

On nv31-50, PBUS's IRQ line is shared with GPIOs IRQs.

It seems like nv10-31 GPIO interruptions aren't well handled. I kept the
original behaviour but it is wrong and may lead to an IRQ storm.

Since we enable all PBUS IRQs, we need a way to avoid being stormed if we
don't handle them. The solution I used was to mask the IRQs that have not been
handled. This will also print one message in the logs to let us know.

v2: drop the shared intr handler because of was racy
v3: style fixes
v4: drop a useless construct in the chipset-dependent INTR
v5: add BUS to the disable mask
v6 (Ben Skeggs):
- general tidy to match the rest of the driver's style
- nva3->nvc0, nva3 can be serviced just fine with nv50.c, rnndb even notes
  that the THERM_ALARM bit got left in the hw until fermi anyway.. so, it's
  not going to conflict
- removed the peephole and user stuff, for the moment.. will handle them
  later if we find a good reason to actually care..
- limited INTR_EN to just what we can handle for now, mostly to prevent
  spam of unknown status bits (seen on at least nv4x)

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Martin Peres <martin.peres@labri.fr>

4 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpu/drm/nouveau/core/subdev/mc/nv04.c b/drivers/gpu/drm/nouveau/core/subdev/mc/nv04.c
index 23ebe47..89da8fa 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/mc/nv04.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mc/nv04.c
@@ -37,7 +37,7 @@ nv04_mc_intr[] = {
 	{ 0x00100000, NVDEV_SUBDEV_TIMER },
 	{ 0x01000000, NVDEV_ENGINE_DISP },	/* NV04- PCRTC0 */
 	{ 0x02000000, NVDEV_ENGINE_DISP },	/* NV11- PCRTC1 */
-	{ 0x10000000, NVDEV_SUBDEV_GPIO },	/* PBUS */
+	{ 0x10000000, NVDEV_SUBDEV_BUS },
 	{ 0x80000000, NVDEV_ENGINE_SW },
 	{}
 };
diff --git a/drivers/gpu/drm/nouveau/core/subdev/mc/nv50.c b/drivers/gpu/drm/nouveau/core/subdev/mc/nv50.c
index 8d759f8..5965add 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/mc/nv50.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mc/nv50.c
@@ -38,6 +38,7 @@ nv50_mc_intr[] = {
 	{ 0x00100000, NVDEV_SUBDEV_TIMER },
 	{ 0x00200000, NVDEV_SUBDEV_GPIO },
 	{ 0x04000000, NVDEV_ENGINE_DISP },
+	{ 0x10000000, NVDEV_SUBDEV_BUS },
 	{ 0x80000000, NVDEV_ENGINE_SW },
 	{ 0x0000d101, NVDEV_SUBDEV_FB },
 	{},
diff --git a/drivers/gpu/drm/nouveau/core/subdev/mc/nv98.c b/drivers/gpu/drm/nouveau/core/subdev/mc/nv98.c
index ceb5c83..b93fd09 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/mc/nv98.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mc/nv98.c
@@ -39,6 +39,7 @@ nv98_mc_intr[] = {
 	{ 0x00200000, NVDEV_SUBDEV_GPIO },
 	{ 0x00400000, NVDEV_ENGINE_COPY0 },	/* NVA3-     */
 	{ 0x04000000, NVDEV_ENGINE_DISP },
+	{ 0x10000000, NVDEV_SUBDEV_BUS },
 	{ 0x80000000, NVDEV_ENGINE_SW },
 	{ 0x0040d101, NVDEV_SUBDEV_FB },
 	{},
diff --git a/drivers/gpu/drm/nouveau/core/subdev/mc/nvc0.c b/drivers/gpu/drm/nouveau/core/subdev/mc/nvc0.c
index 9279668..42bbf72 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/mc/nvc0.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mc/nvc0.c
@@ -36,11 +36,13 @@ nvc0_mc_intr[] = {
 	{ 0x00000100, NVDEV_ENGINE_FIFO },
 	{ 0x00001000, NVDEV_ENGINE_GR },
 	{ 0x00008000, NVDEV_ENGINE_BSP },
+	{ 0x00040000, NVDEV_SUBDEV_THERM },
 	{ 0x00020000, NVDEV_ENGINE_VP },
 	{ 0x00100000, NVDEV_SUBDEV_TIMER },
 	{ 0x00200000, NVDEV_SUBDEV_GPIO },
 	{ 0x02000000, NVDEV_SUBDEV_LTCG },
 	{ 0x04000000, NVDEV_ENGINE_DISP },
+	{ 0x10000000, NVDEV_SUBDEV_BUS },
 	{ 0x40000000, NVDEV_SUBDEV_IBUS },
 	{ 0x80000000, NVDEV_ENGINE_SW },
 	{},