drm/gk104/pwr: implement PGOB disable method

As documented at:

ftp://download.nvidia.com/open-gpu-doc/gk104-disable-graphics-power-gating/1/gk104-disable-graphics-power-gating.txt

NVIDIA were not able document the steps necessary to detect whether this
is required or not at this time.  However, they did confirm that this
procedure is safe to perform unconditionally on GK104/6.  GK107 does not
have the power gating feature, and it was recommended that we do not
perform these steps there as the effects were not verified.

The disable path is from observing the binary driver, and not
documented in the link above.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/Makefile

@@ -169,6 +169,7 @@ nouveau-y += core/subdev/pwr/memx.o
 nouveau-y += core/subdev/pwr/nva3.o
 nouveau-y += core/subdev/pwr/nvc0.o
 nouveau-y += core/subdev/pwr/nvd0.o
+nouveau-y += core/subdev/pwr/gk104.o
 nouveau-y += core/subdev/pwr/nv108.o
 nouveau-y += core/subdev/therm/base.o
 nouveau-y += core/subdev/therm/fan.o

drivers/gpu/drm/nouveau/core/engine/device/nve0.c

@@ -75,7 +75,7 @@ nve0_identify(struct nouveau_device *device)
 		device->oclass[NVDEV_SUBDEV_INSTMEM] =  nv50_instmem_oclass;
 		device->oclass[NVDEV_SUBDEV_VM     ] = &nvc0_vmmgr_oclass;
 		device->oclass[NVDEV_SUBDEV_BAR    ] = &nvc0_bar_oclass;
-		device->oclass[NVDEV_SUBDEV_PWR    ] =  nvd0_pwr_oclass;
+		device->oclass[NVDEV_SUBDEV_PWR    ] =  gk104_pwr_oclass;
 		device->oclass[NVDEV_SUBDEV_VOLT   ] = &nv40_volt_oclass;
 		device->oclass[NVDEV_ENGINE_DMAOBJ ] = &nvd0_dmaeng_oclass;
 		device->oclass[NVDEV_ENGINE_FIFO   ] =  nve0_fifo_oclass;
@@ -141,7 +141,7 @@ nve0_identify(struct nouveau_device *device)
 		device->oclass[NVDEV_SUBDEV_INSTMEM] =  nv50_instmem_oclass;
 		device->oclass[NVDEV_SUBDEV_VM     ] = &nvc0_vmmgr_oclass;
 		device->oclass[NVDEV_SUBDEV_BAR    ] = &nvc0_bar_oclass;
-		device->oclass[NVDEV_SUBDEV_PWR    ] =  nvd0_pwr_oclass;
+		device->oclass[NVDEV_SUBDEV_PWR    ] =  gk104_pwr_oclass;
 		device->oclass[NVDEV_SUBDEV_VOLT   ] = &nv40_volt_oclass;
 		device->oclass[NVDEV_ENGINE_DMAOBJ ] = &nvd0_dmaeng_oclass;
 		device->oclass[NVDEV_ENGINE_FIFO   ] =  nve0_fifo_oclass;

drivers/gpu/drm/nouveau/core/include/subdev/pwr.h

@@ -24,6 +24,7 @@ struct nouveau_pwr {
 	} recv;
 
 	int  (*message)(struct nouveau_pwr *, u32[2], u32, u32, u32, u32);
+	void (*pgob)(struct nouveau_pwr *, bool);
 };
 
 static inline struct nouveau_pwr *
@@ -35,6 +36,7 @@ nouveau_pwr(void *obj)
 extern struct nouveau_oclass *nva3_pwr_oclass;
 extern struct nouveau_oclass *nvc0_pwr_oclass;
 extern struct nouveau_oclass *nvd0_pwr_oclass;
+extern struct nouveau_oclass *gk104_pwr_oclass;
 extern struct nouveau_oclass *nv108_pwr_oclass;
 
 /* interface to MEMX process running on PPWR */

drivers/gpu/drm/nouveau/core/subdev/pwr/base.c

@@ -26,6 +26,14 @@
 
 #include "priv.h"
 
+static void
+nouveau_pwr_pgob(struct nouveau_pwr *ppwr, bool enable)
+{
+	const struct nvkm_pwr_impl *impl = (void *)nv_oclass(ppwr);
+	if (impl->pgob)
+		impl->pgob(ppwr, enable);
+}
+
 static int
 nouveau_pwr_send(struct nouveau_pwr *ppwr, u32 reply[2],
 		 u32 process, u32 message, u32 data0, u32 data1)
@@ -188,6 +196,7 @@ _nouveau_pwr_init(struct nouveau_object *object)
 
 	nv_subdev(ppwr)->intr = nouveau_pwr_intr;
 	ppwr->message = nouveau_pwr_send;
+	ppwr->pgob = nouveau_pwr_pgob;
 
 	/* prevent previous ucode from running, wait for idle, reset */
 	nv_wr32(ppwr, 0x10a014, 0x0000ffff); /* INTR_EN_CLR = ALL */

drivers/gpu/drm/nouveau/core/subdev/pwr/gk104.c

+/*
+ * Copyright 2013 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Ben Skeggs
+ */
+
+#include "priv.h"
+
+#define nvd0_pwr_code gk104_pwr_code
+#define nvd0_pwr_data gk104_pwr_data
+#include "fuc/nvd0.fuc.h"
+
+static void
+gk104_pwr_pgob(struct nouveau_pwr *ppwr, bool enable)
+{
+	nv_mask(ppwr, 0x000200, 0x00001000, 0x00000000);
+	nv_rd32(ppwr, 0x000200);
+	nv_mask(ppwr, 0x000200, 0x08000000, 0x08000000);
+	msleep(50);
+
+	nv_mask(ppwr, 0x10a78c, 0x00000002, 0x00000002);
+	nv_mask(ppwr, 0x10a78c, 0x00000001, 0x00000001);
+	nv_mask(ppwr, 0x10a78c, 0x00000001, 0x00000000);
+
+	nv_mask(ppwr, 0x020004, 0xc0000000, enable ? 0xc0000000 : 0x40000000);
+	msleep(50);
+
+	nv_mask(ppwr, 0x10a78c, 0x00000002, 0x00000000);
+	nv_mask(ppwr, 0x10a78c, 0x00000001, 0x00000001);
+	nv_mask(ppwr, 0x10a78c, 0x00000001, 0x00000000);
+
+	nv_mask(ppwr, 0x000200, 0x08000000, 0x00000000);
+	nv_mask(ppwr, 0x000200, 0x00001000, 0x00001000);
+	nv_rd32(ppwr, 0x000200);
+}
+
+struct nouveau_oclass *
+gk104_pwr_oclass = &(struct nvkm_pwr_impl) {
+	.base.handle = NV_SUBDEV(PWR, 0xe4),
+	.base.ofuncs = &(struct nouveau_ofuncs) {
+		.ctor = _nouveau_pwr_ctor,
+		.dtor = _nouveau_pwr_dtor,
+		.init = _nouveau_pwr_init,
+		.fini = _nouveau_pwr_fini,
+	},
+	.code.data = gk104_pwr_code,
+	.code.size = sizeof(gk104_pwr_code),
+	.data.data = gk104_pwr_data,
+	.data.size = sizeof(gk104_pwr_data),
+	.pgob = gk104_pwr_pgob,
+}.base;

drivers/gpu/drm/nouveau/core/subdev/pwr/priv.h

@@ -37,6 +37,8 @@ struct nvkm_pwr_impl {
 		u32 *data;
 		u32  size;
 	} data;
+
+	void (*pgob)(struct nouveau_pwr *, bool);
 };
 
 #endif