support for platform devices

Upcoming mobile Kepler GPUs (such as GK20A) use the platform bus instead
of PCI to which Nouveau is tightly dependent. This patch allows Nouveau
to handle platform devices by:

- abstracting PCI-dependent functions that were typically used for
  resource querying and page mapping,
- introducing a nv_device_is_pci() function that allows to make
  PCI-dependent code conditional,
- providing a nouveau_drm_platform_probe() function that takes a GPU
  platform device to be probed.

Core code as well as engine/subdev drivers are updated wherever possible
to make use of these functions. Some older drivers are too dependent on
PCI to be properly updated, but all newer code on which future chips may
depend should at least be runnable with platform devices.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Author: Gnurou

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

@@ -131,8 +131,8 @@ nouveau_devobj_ctor(struct nouveau_object *parent,
 	if (ret)
 		return ret;
 
-	mmio_base = pci_resource_start(device->pdev, 0);
-	mmio_size = pci_resource_len(device->pdev, 0);
+	mmio_base = nv_device_resource_start(device, 0);
+	mmio_size = nv_device_resource_len(device, 0);
 
 	/* translate api disable mask into internal mapping */
 	disable = args->debug0;
@@ -448,6 +448,72 @@ nouveau_device_dtor(struct nouveau_object *object)
 	nouveau_engine_destroy(&device->base);
 }
 
+resource_size_t
+nv_device_resource_start(struct nouveau_device *device, unsigned int bar)
+{
+	if (nv_device_is_pci(device)) {
+		return pci_resource_start(device->pdev, bar);
+	} else {
+		struct resource *res;
+		res = platform_get_resource(device->platformdev,
+					    IORESOURCE_MEM, bar);
+		if (!res)
+			return 0;
+		return res->start;
+	}
+}
+
+resource_size_t
+nv_device_resource_len(struct nouveau_device *device, unsigned int bar)
+{
+	if (nv_device_is_pci(device)) {
+		return pci_resource_len(device->pdev, bar);
+	} else {
+		struct resource *res;
+		res = platform_get_resource(device->platformdev,
+					    IORESOURCE_MEM, bar);
+		if (!res)
+			return 0;
+		return resource_size(res);
+	}
+}
+
+dma_addr_t
+nv_device_map_page(struct nouveau_device *device, struct page *page)
+{
+	dma_addr_t ret;
+
+	if (nv_device_is_pci(device)) {
+		ret = pci_map_page(device->pdev, page, 0, PAGE_SIZE,
+				   PCI_DMA_BIDIRECTIONAL);
+		if (pci_dma_mapping_error(device->pdev, ret))
+			ret = 0;
+	} else {
+		ret = page_to_phys(page);
+	}
+
+	return ret;
+}
+
+void
+nv_device_unmap_page(struct nouveau_device *device, dma_addr_t addr)
+{
+	if (nv_device_is_pci(device))
+		pci_unmap_page(device->pdev, addr, PAGE_SIZE,
+			       PCI_DMA_BIDIRECTIONAL);
+}
+
+int
+nv_device_get_irq(struct nouveau_device *device, bool stall)
+{
+	if (nv_device_is_pci(device)) {
+		return device->pdev->irq;
+	} else {
+		return platform_get_irq_byname(device->platformdev,
+					       stall ? "stall" : "nonstall");
+	}
+}
+
 static struct nouveau_oclass
 nouveau_device_oclass = {
 	.handle = NV_ENGINE(DEVICE, 0x00),
@@ -459,8 +525,8 @@ nouveau_device_oclass = {
 };
 
 int
-nouveau_device_create_(struct pci_dev *pdev, u64 name, const char *sname,
-		       const char *cfg, const char *dbg,
+nouveau_device_create_(void *dev, enum nv_bus_type type, u64 name,
+		       const char *sname, const char *cfg, const char *dbg,
 		       int length, void **pobject)
 {
 	struct nouveau_device *device;
@@ -478,7 +544,14 @@ nouveau_device_create_(struct pci_dev *pdev, u64 name, const char *sname,
 	if (ret)
 		goto done;
 
-	device->pdev = pdev;
+	switch (type) {
+	case NOUVEAU_BUS_PCI:
+		device->pdev = dev;
+		break;
+	case NOUVEAU_BUS_PLATFORM:
+		device->platformdev = dev;
+		break;
+	}
 	device->handle = name;
 	device->cfgopt = cfg;
 	device->dbgopt = dbg;

drivers/gpu/drm/nouveau/core/engine/falcon.c

@@ -119,7 +119,7 @@ _nouveau_falcon_init(struct nouveau_object *object)
 		snprintf(name, sizeof(name), "nouveau/nv%02x_fuc%03x",
 			 device->chipset, falcon->addr >> 12);
 
-		ret = request_firmware(&fw, name, &device->pdev->dev);
+		ret = request_firmware(&fw, name, nv_device_base(device));
 		if (ret == 0) {
 			falcon->code.data = vmemdup(fw->data, fw->size);
 			falcon->code.size = fw->size;
@@ -138,7 +138,7 @@ _nouveau_falcon_init(struct nouveau_object *object)
 		snprintf(name, sizeof(name), "nouveau/nv%02x_fuc%03xd",
 			 device->chipset, falcon->addr >> 12);
 
-		ret = request_firmware(&fw, name, &device->pdev->dev);
+		ret = request_firmware(&fw, name, nv_device_base(device));
 		if (ret) {
 			nv_error(falcon, "unable to load firmware data\n");
 			return ret;
@@ -153,7 +153,7 @@ _nouveau_falcon_init(struct nouveau_object *object)
 		snprintf(name, sizeof(name), "nouveau/nv%02x_fuc%03xc",
 			 device->chipset, falcon->addr >> 12);
 
-		ret = request_firmware(&fw, name, &device->pdev->dev);
+		ret = request_firmware(&fw, name, nv_device_base(device));
 		if (ret) {
 			nv_error(falcon, "unable to load firmware code\n");
 			return ret;

drivers/gpu/drm/nouveau/core/engine/fifo/base.c

@@ -86,7 +86,7 @@ nouveau_fifo_channel_create_(struct nouveau_object *parent,
 	}
 
 	/* map fifo control registers */
-	chan->user = ioremap(pci_resource_start(device->pdev, bar) + addr +
+	chan->user = ioremap(nv_device_resource_start(device, bar) + addr +
 			     (chan->chid * size), size);
 	if (!chan->user)
 		return -EFAULT;

drivers/gpu/drm/nouveau/core/engine/graph/nv20.c

@@ -349,7 +349,7 @@ nv20_graph_init(struct nouveau_object *object)
 	nv_wr32(priv, NV10_PGRAPH_SURFACE, tmp);
 
 	/* begin RAM config */
-	vramsz = pci_resource_len(nv_device(priv)->pdev, 0) - 1;
+	vramsz = nv_device_resource_len(nv_device(priv), 0) - 1;
 	nv_wr32(priv, 0x4009A4, nv_rd32(priv, 0x100200));
 	nv_wr32(priv, 0x4009A8, nv_rd32(priv, 0x100204));
 	nv_wr32(priv, NV10_PGRAPH_RDI_INDEX, 0x00EA0000);

drivers/gpu/drm/nouveau/core/engine/graph/nv40.c

@@ -484,7 +484,7 @@ nv40_graph_init(struct nouveau_object *object)
 		engine->tile_prog(engine, i);
 
 	/* begin RAM config */
-	vramsz = pci_resource_len(nv_device(priv)->pdev, 0) - 1;
+	vramsz = nv_device_resource_len(nv_device(priv), 0) - 1;
 	switch (nv_device(priv)->chipset) {
 	case 0x40:
 		nv_wr32(priv, 0x4009A4, nv_rd32(priv, 0x100200));

drivers/gpu/drm/nouveau/core/engine/graph/nvc0.c

@@ -1091,10 +1091,10 @@ nvc0_graph_ctor_fw(struct nvc0_graph_priv *priv, const char *fwname,
 	int ret;
 
 	snprintf(f, sizeof(f), "nouveau/nv%02x_%s", device->chipset, fwname);
-	ret = request_firmware(&fw, f, &device->pdev->dev);
+	ret = request_firmware(&fw, f, nv_device_base(device));
 	if (ret) {
 		snprintf(f, sizeof(f), "nouveau/%s", fwname);
-		ret = request_firmware(&fw, f, &device->pdev->dev);
+		ret = request_firmware(&fw, f, nv_device_base(device));
 		if (ret) {
 			nv_error(priv, "failed to load %s\n", fwname);
 			return ret;

drivers/gpu/drm/nouveau/core/engine/xtensa.c

@@ -112,7 +112,7 @@ _nouveau_xtensa_init(struct nouveau_object *object)
 		snprintf(name, sizeof(name), "nouveau/nv84_xuc%03x",
 			 xtensa->addr >> 12);
 
-		ret = request_firmware(&fw, name, &device->pdev->dev);
+		ret = request_firmware(&fw, name, nv_device_base(device));
 		if (ret) {
 			nv_warn(xtensa, "unable to load firmware %s\n", name);
 			return ret;

drivers/gpu/drm/nouveau/core/include/core/device.h

@@ -66,6 +66,7 @@ struct nouveau_device {
 	struct list_head head;
 
 	struct pci_dev *pdev;
+	struct platform_device *platformdev;
 	u64 handle;
 
 	const char *cfgopt;
@@ -142,4 +143,32 @@ nv_device_match(struct nouveau_object *object, u16 dev, u16 ven, u16 sub)
 	       device->pdev->subsystem_device == sub;
 }
 
+static inline bool
+nv_device_is_pci(struct nouveau_device *device)
+{
+	return device->pdev != NULL;
+}
+
+static inline struct device *
+nv_device_base(struct nouveau_device *device)
+{
+	return nv_device_is_pci(device) ? &device->pdev->dev :
+					  &device->platformdev->dev;
+}
+
+resource_size_t
+nv_device_resource_start(struct nouveau_device *device, unsigned int bar);
+
+resource_size_t
+nv_device_resource_len(struct nouveau_device *device, unsigned int bar);
+
+dma_addr_t
+nv_device_map_page(struct nouveau_device *device, struct page *page);
+
+void
+nv_device_unmap_page(struct nouveau_device *device, dma_addr_t addr);
+
+int
+nv_device_get_irq(struct nouveau_device *device, bool stall);
+
 #endif

drivers/gpu/drm/nouveau/core/include/engine/device.h

@@ -3,11 +3,20 @@
 
 #include <core/device.h>
 
-#define nouveau_device_create(p,n,s,c,d,u)                                     \
-	nouveau_device_create_((p), (n), (s), (c), (d), sizeof(**u), (void **)u)
+struct platform_device;
 
-int  nouveau_device_create_(struct pci_dev *, u64 name, const char *sname,
-			    const char *cfg, const char *dbg, int, void **);
+enum nv_bus_type {
+	NOUVEAU_BUS_PCI,
+	NOUVEAU_BUS_PLATFORM,
+};
+
+#define nouveau_device_create(p,t,n,s,c,d,u)                                   \
+	nouveau_device_create_((void *)(p), (t), (n), (s), (c), (d),           \
+			       sizeof(**u), (void **)u)
+
+int  nouveau_device_create_(void *, enum nv_bus_type type, u64 name,
+			    const char *sname, const char *cfg, const char *dbg,
+			    int, void **);
 
 int nv04_identify(struct nouveau_device *);
 int nv10_identify(struct nouveau_device *);

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

@@ -12,6 +12,7 @@ struct nouveau_mc_intr {
 struct nouveau_mc {
 	struct nouveau_subdev base;
 	bool use_msi;
+	unsigned int irq;
 };
 
 static inline struct nouveau_mc *