diff mbox series

[v2,08/10] MIPS: SGI-IP27: use generic PCI driver

Message ID 20190219155728.19163-9-tbogendoerfer@suse.de (mailing list archive)
State Changes Requested
Headers show
Series MIPS: SGI-IP27 rework | expand

Commit Message

Thomas Bogendoerfer Feb. 19, 2019, 3:57 p.m. UTC
Converted bridge code to a platform driver using the PCI generic driver
framework and use adding platform devices during xtalk scan. This allows
easier sharing bridge driver for other SGI platforms like IP30 (Octane) and
IP35 (Origin 3k, Fuel, Tezro).

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 arch/mips/Kconfig                                  |   2 +
 arch/mips/include/asm/dma-direct.h                 |   2 +
 arch/mips/include/asm/mach-generic/dma-direct.h    |   7 +
 arch/mips/include/asm/mach-ip27/dma-direct.h       |  20 ++
 arch/mips/include/asm/mach-ip27/topology.h         |  13 +-
 arch/mips/include/asm/pci.h                        |   8 +
 arch/mips/include/asm/pci/bridge.h                 |   6 +-
 arch/mips/include/asm/xtalk/xtalk.h                |   9 -
 arch/mips/pci/Makefile                             |   1 -
 arch/mips/pci/pci-ip27.c                           | 214 ----------------
 arch/mips/sgi-ip27/ip27-init.c                     |   2 +
 arch/mips/sgi-ip27/ip27-xtalk.c                    |  31 ++-
 drivers/pci/controller/Kconfig                     |   3 +
 drivers/pci/controller/Makefile                    |   1 +
 .../pci/controller/pci-xtalk-bridge.c              | 278 +++++++++++++++++----
 include/linux/platform_data/xtalk-bridge.h         |  17 ++
 16 files changed, 312 insertions(+), 302 deletions(-)
 create mode 100644 arch/mips/include/asm/mach-generic/dma-direct.h
 create mode 100644 arch/mips/include/asm/mach-ip27/dma-direct.h
 delete mode 100644 arch/mips/pci/pci-ip27.c
 rename arch/mips/pci/ops-bridge.c => drivers/pci/controller/pci-xtalk-bridge.c (52%)
 create mode 100644 include/linux/platform_data/xtalk-bridge.h

Comments

Christoph Hellwig Feb. 22, 2019, 2:46 p.m. UTC | #1
> diff --git a/arch/mips/include/asm/dma-direct.h b/arch/mips/include/asm/dma-direct.h
> index b5c240806e1b..bd11e7934df1 100644
> --- a/arch/mips/include/asm/dma-direct.h
> +++ b/arch/mips/include/asm/dma-direct.h
> @@ -2,6 +2,8 @@
>  #ifndef _MIPS_DMA_DIRECT_H
>  #define _MIPS_DMA_DIRECT_H 1
>  
> +#include <dma-direct.h>
> +
>  static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
>  {
>  	if (!dev->dma_mask)

How is your mach dma-direct.h scheme going to work, given that
we already have non-inline declarations of __phys_to_dma / __dma_to_phys
in this file?

Also this really should go into a separate commit, and we should either
have all of these functions inline or none.  Having all of them out
of line seemed a lot saner to me to avoid all the mach header mess.

Also there seem to be a lot of randomw whitespace / brace cleanups
in this patch.  Shouldn't those be split out as well?
Thomas Bogendoerfer Feb. 27, 2019, 5:10 p.m. UTC | #2
On Fri, 22 Feb 2019 06:46:29 -0800
Christoph Hellwig <hch@infradead.org> wrote:

> > diff --git a/arch/mips/include/asm/dma-direct.h b/arch/mips/include/asm/dma-direct.h
> > index b5c240806e1b..bd11e7934df1 100644
> > --- a/arch/mips/include/asm/dma-direct.h
> > +++ b/arch/mips/include/asm/dma-direct.h
> > @@ -2,6 +2,8 @@
> >  #ifndef _MIPS_DMA_DIRECT_H
> >  #define _MIPS_DMA_DIRECT_H 1
> >  
> > +#include <dma-direct.h>
> > +
> >  static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
> >  {
> >  	if (!dev->dma_mask)
> 
> How is your mach dma-direct.h scheme going to work, given that
> we already have non-inline declarations of __phys_to_dma / __dma_to_phys
> in this file?

the compiler is fine with the declarations, that's why I left the non-inline
prototypes as they are

> Also this really should go into a separate commit, and we should either
> have all of these functions inline or none.  Having all of them out
> of line seemed a lot saner to me to avoid all the mach header mess.

hmm, so your inline version in include/linux/dma-direct.h is ok, while
doing the same for MIPS in an other header files isn't ? Sounds inconsistent
to me.

Anyway I'll move __phys_to_dma/__dma_to_phy into a fitting/new .c file in
the next version of the series.

Thomas.
diff mbox series

Patch

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 93b88e8e72d0..57a424e82a18 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -678,6 +678,8 @@  config SGI_IP27
 	select HAVE_PCI
 	select IRQ_MIPS_CPU
 	select NR_CPUS_DEFAULT_64
+	select PCI_DRIVERS_GENERIC
+	select PCI_XTALK_BRIDGE
 	select SYS_HAS_CPU_R10000
 	select SYS_SUPPORTS_64BIT_KERNEL
 	select SYS_SUPPORTS_BIG_ENDIAN
diff --git a/arch/mips/include/asm/dma-direct.h b/arch/mips/include/asm/dma-direct.h
index b5c240806e1b..bd11e7934df1 100644
--- a/arch/mips/include/asm/dma-direct.h
+++ b/arch/mips/include/asm/dma-direct.h
@@ -2,6 +2,8 @@ 
 #ifndef _MIPS_DMA_DIRECT_H
 #define _MIPS_DMA_DIRECT_H 1
 
+#include <dma-direct.h>
+
 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	if (!dev->dma_mask)
diff --git a/arch/mips/include/asm/mach-generic/dma-direct.h b/arch/mips/include/asm/mach-generic/dma-direct.h
new file mode 100644
index 000000000000..2d2c187dcd42
--- /dev/null
+++ b/arch/mips/include/asm/mach-generic/dma-direct.h
@@ -0,0 +1,7 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_MACH_GENERIC_DMA_DIRECT_H
+#define __ASM_MACH_GENERIC_DMA_DIRECT_H
+
+/* Intentionally empty file ...  */
+
+#endif /* __ASM_MACH_GENERIC_DMA_DIRECT_H */
diff --git a/arch/mips/include/asm/mach-ip27/dma-direct.h b/arch/mips/include/asm/mach-ip27/dma-direct.h
new file mode 100644
index 000000000000..ec9856dfe2db
--- /dev/null
+++ b/arch/mips/include/asm/mach-ip27/dma-direct.h
@@ -0,0 +1,20 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_MACH_IP27_DMA_DIRECT_H
+#define __ASM_MACH_IP27_DMA_DIRECT_H
+
+#include <asm/pci/bridge.h>
+
+static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct bridge_controller *bc = BRIDGE_CONTROLLER(pdev->bus);
+
+	return bc->baddr + paddr;
+}
+
+static inline phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dma_addr)
+{
+	return dma_addr & ~(0xffUL << 56);
+}
+
+#endif /* __ASM_MACH_IP27_DMA_DIRECT_H */
diff --git a/arch/mips/include/asm/mach-ip27/topology.h b/arch/mips/include/asm/mach-ip27/topology.h
index 42ea1313626c..3cd03a74187e 100644
--- a/arch/mips/include/asm/mach-ip27/topology.h
+++ b/arch/mips/include/asm/mach-ip27/topology.h
@@ -7,18 +7,9 @@ 
 #include <asm/mmzone.h>
 
 struct cpuinfo_ip27 {
-//	cpuid_t		p_cpuid;	/* PROM assigned cpuid */
 	cnodeid_t	p_nodeid;	/* my node ID in compact-id-space */
 	nasid_t		p_nasid;	/* my node ID in numa-as-id-space */
 	unsigned char	p_slice;	/* Physical position on node board */
-#if 0
-	unsigned long		loops_per_sec;
-	unsigned long		ipi_count;
-	unsigned long		irq_attempt[NR_IRQS];
-	unsigned long		smp_local_irq_count;
-	unsigned long		prof_multiplier;
-	unsigned long		prof_counter;
-#endif
 };
 
 extern struct cpuinfo_ip27 sn_cpu_info[NR_CPUS];
@@ -27,10 +18,8 @@  extern struct cpuinfo_ip27 sn_cpu_info[NR_CPUS];
 #define cpumask_of_node(node)	((node) == -1 ?				\
 				 cpu_all_mask :				\
 				 &hub_data(node)->h_cpus)
-struct pci_bus;
-extern int pcibus_to_node(struct pci_bus *);
 
-#define cpumask_of_pcibus(bus)	(cpu_online_mask)
+#define cpumask_of_pcibus(bus)	(cpumask_of_node(pcibus_to_node(bus)))
 
 extern unsigned char __node_distances[MAX_COMPACT_NODES][MAX_COMPACT_NODES];
 
diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
index 436099883022..70d1e51a7ca2 100644
--- a/arch/mips/include/asm/pci.h
+++ b/arch/mips/include/asm/pci.h
@@ -147,4 +147,12 @@  static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
 	return channel ? 15 : 14;
 }
 
+#ifdef CONFIG_SGI_IP27
+/* Returns the node based on pci bus */
+static inline int pcibus_to_node(struct pci_bus *bus)
+{
+	return dev_to_node(&bus->dev);
+}
+#endif
+
 #endif /* _ASM_PCI_H */
diff --git a/arch/mips/include/asm/pci/bridge.h b/arch/mips/include/asm/pci/bridge.h
index 23574c27eb40..457ff868a027 100644
--- a/arch/mips/include/asm/pci/bridge.h
+++ b/arch/mips/include/asm/pci/bridge.h
@@ -801,15 +801,13 @@  struct bridge_err_cmdword {
 #define PCI64_ATTR_RMF_SHFT	48
 
 struct bridge_controller {
-	struct pci_controller	pc;
 	struct resource		mem;
 	struct resource		io;
 	struct resource		busn;
 	struct bridge_regs	*base;
-	nasid_t			nasid;
-	unsigned int		widget_id;
 	u64			baddr;
 	unsigned int		pci_int[8];
+	nasid_t			nasid;
 };
 
 #define BRIDGE_CONTROLLER(bus) \
@@ -824,6 +822,4 @@  struct bridge_controller {
 
 extern int request_bridge_irq(struct bridge_controller *bc, int pin);
 
-extern struct pci_ops bridge_pci_ops;
-
 #endif /* _ASM_PCI_BRIDGE_H */
diff --git a/arch/mips/include/asm/xtalk/xtalk.h b/arch/mips/include/asm/xtalk/xtalk.h
index 26d2ed1fa917..680e7efebbaf 100644
--- a/arch/mips/include/asm/xtalk/xtalk.h
+++ b/arch/mips/include/asm/xtalk/xtalk.h
@@ -47,15 +47,6 @@  typedef struct xtalk_piomap_s *xtalk_piomap_t;
 #define XIO_PORT(x)	((xwidgetnum_t)(((x)&XIO_PORT_BITS) >> XIO_PORT_SHIFT))
 #define XIO_PACK(p, o)	((((uint64_t)(p))<<XIO_PORT_SHIFT) | ((o)&XIO_ADDR_BITS))
 
-#ifdef CONFIG_PCI
-extern int bridge_probe(nasid_t nasid, int widget, int masterwid);
-#else
-static inline int bridge_probe(nasid_t nasid, int widget, int masterwid)
-{
-	return 0;
-}
-#endif
-
 #endif /* !__ASSEMBLY__ */
 
 #endif /* _ASM_XTALK_XTALK_H */
diff --git a/arch/mips/pci/Makefile b/arch/mips/pci/Makefile
index 8185a2bfaf09..0225d83d6681 100644
--- a/arch/mips/pci/Makefile
+++ b/arch/mips/pci/Makefile
@@ -38,7 +38,6 @@  obj-$(CONFIG_MIPS_MALTA)	+= fixup-malta.o pci-malta.o
 obj-$(CONFIG_PMC_MSP7120_GW)	+= fixup-pmcmsp.o ops-pmcmsp.o
 obj-$(CONFIG_PMC_MSP7120_EVAL)	+= fixup-pmcmsp.o ops-pmcmsp.o
 obj-$(CONFIG_PMC_MSP7120_FPGA)	+= fixup-pmcmsp.o ops-pmcmsp.o
-obj-$(CONFIG_SGI_IP27)		+= ops-bridge.o pci-ip27.o
 obj-$(CONFIG_SGI_IP32)		+= fixup-ip32.o ops-mace.o pci-ip32.o
 obj-$(CONFIG_SIBYTE_SB1250)	+= fixup-sb1250.o pci-sb1250.o
 obj-$(CONFIG_SIBYTE_BCM112X)	+= fixup-sb1250.o pci-sb1250.o
diff --git a/arch/mips/pci/pci-ip27.c b/arch/mips/pci/pci-ip27.c
deleted file mode 100644
index 3c177b4d0609..000000000000
--- a/arch/mips/pci/pci-ip27.c
+++ /dev/null
@@ -1,214 +0,0 @@ 
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2003 Christoph Hellwig (hch@lst.de)
- * Copyright (C) 1999, 2000, 04 Ralf Baechle (ralf@linux-mips.org)
- * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
- */
-#include <linux/kernel.h>
-#include <linux/export.h>
-#include <linux/pci.h>
-#include <linux/smp.h>
-#include <linux/dma-direct.h>
-#include <asm/sn/arch.h>
-#include <asm/pci/bridge.h>
-#include <asm/paccess.h>
-#include <asm/sn/intr.h>
-#include <asm/sn/sn0/hub.h>
-
-/*
- * Max #PCI busses we can handle; ie, max #PCI bridges.
- */
-#define MAX_PCI_BUSSES		40
-
-/*
- * XXX: No kmalloc available when we do our crosstalk scan,
- *	we should try to move it later in the boot process.
- */
-static struct bridge_controller bridges[MAX_PCI_BUSSES];
-
-extern struct pci_ops bridge_pci_ops;
-
-int bridge_probe(nasid_t nasid, int widget_id, int masterwid)
-{
-	unsigned long offset = NODE_OFFSET(nasid);
-	struct bridge_controller *bc;
-	static int num_bridges = 0;
-	int slot;
-
-	pci_set_flags(PCI_PROBE_ONLY);
-
-	printk("a bridge\n");
-
-	/* XXX: kludge alert.. */
-	if (!num_bridges)
-		ioport_resource.end = ~0UL;
-
-	bc = &bridges[num_bridges];
-
-	bc->pc.pci_ops		= &bridge_pci_ops;
-	bc->pc.mem_resource	= &bc->mem;
-	bc->pc.io_resource	= &bc->io;
-
-	bc->pc.index		= num_bridges;
-
-	bc->mem.name		= "Bridge PCI MEM";
-	bc->pc.mem_offset	= offset;
-	bc->mem.start		= 0;
-	bc->mem.end		= ~0UL;
-	bc->mem.flags		= IORESOURCE_MEM;
-
-	bc->io.name		= "Bridge IO MEM";
-	bc->pc.io_offset	= offset;
-	bc->io.start		= 0UL;
-	bc->io.end		= ~0UL;
-	bc->io.flags		= IORESOURCE_IO;
-
-	bc->widget_id = widget_id;
-	bc->nasid = nasid;
-
-	bc->baddr = (u64)masterwid << 60 | PCI64_ATTR_BAR;
-
-	/*
-	 * point to this bridge
-	 */
-	bc->base = (struct bridge_regs *)RAW_NODE_SWIN_BASE(nasid, widget_id);
-
-	/*
-	 * Clear all pending interrupts.
-	 */
-	bridge_write(bc, b_int_rst_stat, BRIDGE_IRR_ALL_CLR);
-
-	/*
-	 * Until otherwise set up, assume all interrupts are from slot 0
-	 */
-	bridge_write(bc, b_int_device, 0x0);
-
-	/*
-	 * swap pio's to pci mem and io space (big windows)
-	 */
-	bridge_set(bc, b_wid_control, BRIDGE_CTRL_IO_SWAP |
-				      BRIDGE_CTRL_MEM_SWAP);
-#ifdef CONFIG_PAGE_SIZE_4KB
-	bridge_clr(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
-#else /* 16kB or larger */
-	bridge_set(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
-#endif
-
-	/*
-	 * Hmm...  IRIX sets additional bits in the address which
-	 * are documented as reserved in the bridge docs.
-	 */
-	bridge_write(bc, b_wid_int_upper, 0x8000 | (masterwid << 16));
-	bridge_write(bc, b_wid_int_lower, 0x01800090); /* PI_INT_PEND_MOD off*/
-	bridge_write(bc, b_dir_map, (masterwid << 20));	/* DMA */
-	bridge_write(bc, b_int_enable, 0);
-
-	for (slot = 0; slot < 8; slot ++) {
-		bridge_set(bc, b_device[slot].reg, BRIDGE_DEV_SWAP_DIR);
-		bc->pci_int[slot] = -1;
-	}
-	bridge_read(bc, b_wid_tflush);	  /* wait until Bridge PIO complete */
-
-	register_pci_controller(&bc->pc);
-
-	num_bridges++;
-
-	return 0;
-}
-
-/*
- * All observed requests have pin == 1. We could have a global here, that
- * gets incremented and returned every time - unfortunately, pci_map_irq
- * may be called on the same device over and over, and need to return the
- * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
- *
- * A given PCI device, in general, should be able to intr any of the cpus
- * on any one of the hubs connected to its xbow.
- */
-int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
-{
-	return 0;
-}
-
-static inline struct pci_dev *bridge_root_dev(struct pci_dev *dev)
-{
-	while (dev->bus->parent) {
-		/* Move up the chain of bridges. */
-		dev = dev->bus->self;
-	}
-
-	return dev;
-}
-
-/* Do platform specific device initialization at pci_enable_device() time */
-int pcibios_plat_dev_init(struct pci_dev *dev)
-{
-	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
-	struct pci_dev *rdev = bridge_root_dev(dev);
-	int slot = PCI_SLOT(rdev->devfn);
-	int irq;
-
-	irq = bc->pci_int[slot];
-	if (irq == -1) {
-		irq = request_bridge_irq(bc, slot);
-		if (irq < 0)
-			return irq;
-
-		bc->pci_int[slot] = irq;
-	}
-	dev->irq = irq;
-
-	return 0;
-}
-
-dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct bridge_controller *bc = BRIDGE_CONTROLLER(pdev->bus);
-
-	return bc->baddr + paddr;
-}
-
-phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dma_addr)
-{
-	return dma_addr & ~(0xffUL << 56);
-}
-
-/*
- * Device might live on a subordinate PCI bus.	XXX Walk up the chain of buses
- * to find the slot number in sense of the bridge device register.
- * XXX This also means multiple devices might rely on conflicting bridge
- * settings.
- */
-
-static inline void pci_disable_swapping(struct pci_dev *dev)
-{
-	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
-	struct bridge_regs *bridge = bc->base;
-	int slot = PCI_SLOT(dev->devfn);
-
-	/* Turn off byte swapping */
-	bridge->b_device[slot].reg &= ~BRIDGE_DEV_SWAP_DIR;
-	bridge->b_widget.w_tflush;	/* Flush */
-}
-
-static void pci_fixup_ioc3(struct pci_dev *d)
-{
-	pci_disable_swapping(d);
-}
-
-#ifdef CONFIG_NUMA
-int pcibus_to_node(struct pci_bus *bus)
-{
-	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
-
-	return bc->nasid;
-}
-EXPORT_SYMBOL(pcibus_to_node);
-#endif /* CONFIG_NUMA */
-
-DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
-	pci_fixup_ioc3);
diff --git a/arch/mips/sgi-ip27/ip27-init.c b/arch/mips/sgi-ip27/ip27-init.c
index 6074efeff894..066b33f50bcc 100644
--- a/arch/mips/sgi-ip27/ip27-init.c
+++ b/arch/mips/sgi-ip27/ip27-init.c
@@ -184,5 +184,7 @@  void __init plat_mem_setup(void)
 
 	ioc3_eth_init();
 
+	ioport_resource.start = 0;
+	ioport_resource.end = ~0UL;
 	set_io_port_base(IO_BASE);
 }
diff --git a/arch/mips/sgi-ip27/ip27-xtalk.c b/arch/mips/sgi-ip27/ip27-xtalk.c
index ce06aaa115ae..8579b651d862 100644
--- a/arch/mips/sgi-ip27/ip27-xtalk.c
+++ b/arch/mips/sgi-ip27/ip27-xtalk.c
@@ -9,6 +9,8 @@ 
 
 #include <linux/kernel.h>
 #include <linux/smp.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/xtalk-bridge.h>
 #include <asm/sn/types.h>
 #include <asm/sn/klconfig.h>
 #include <asm/sn/hub.h>
@@ -20,7 +22,19 @@ 
 #define XXBOW_WIDGET_PART_NUM	0xd000	/* Xbow in Xbridge */
 #define BASE_XBOW_PORT		8     /* Lowest external port */
 
-extern int bridge_probe(nasid_t nasid, int widget, int masterwid);
+static void bridge_platform_create(nasid_t nasid, int widget, int masterwid)
+{
+	struct platform_device *pdev;
+	struct xtalk_bridge_platform_data bridge_data;
+
+	pdev = platform_device_alloc("xtalk-bridge", PLATFORM_DEVID_AUTO);
+	bridge_data.nasid = nasid;
+	bridge_data.widget = widget;
+	bridge_data.masterwid = masterwid;
+	platform_device_add_data(pdev, &bridge_data, sizeof(bridge_data));
+	platform_device_add(pdev);
+	pr_info("xtalk:n%d/%x bridge widget\n", nasid, widget);
+}
 
 static int probe_one_port(nasid_t nasid, int widget, int masterwid)
 {
@@ -31,13 +45,10 @@  static int probe_one_port(nasid_t nasid, int widget, int masterwid)
 		(RAW_NODE_SWIN_BASE(nasid, widget) + WIDGET_ID);
 	partnum = XWIDGET_PART_NUM(widget_id);
 
-	printk(KERN_INFO "Cpu %d, Nasid 0x%x, widget 0x%x (partnum 0x%x) is ",
-			smp_processor_id(), nasid, widget, partnum);
-
 	switch (partnum) {
 	case BRIDGE_WIDGET_PART_NUM:
 	case XBRIDGE_WIDGET_PART_NUM:
-		bridge_probe(nasid, widget, masterwid);
+		bridge_platform_create(nasid, widget, masterwid);
 		break;
 	default:
 		break;
@@ -52,8 +63,6 @@  static int xbow_probe(nasid_t nasid)
 	klxbow_t *xbow_p;
 	unsigned masterwid, i;
 
-	printk("is xbow\n");
-
 	/*
 	 * found xbow, so may have multiple bridges
 	 * need to probe xbow
@@ -117,19 +126,17 @@  static void xtalk_probe_node(cnodeid_t nid)
 		       (RAW_NODE_SWIN_BASE(nasid, 0x0) + WIDGET_ID);
 	partnum = XWIDGET_PART_NUM(widget_id);
 
-	printk(KERN_INFO "Cpu %d, Nasid 0x%x: partnum 0x%x is ",
-			smp_processor_id(), nasid, partnum);
-
 	switch (partnum) {
 	case BRIDGE_WIDGET_PART_NUM:
-		bridge_probe(nasid, 0x8, 0xa);
+		bridge_platform_create(nasid, 0x8, 0xa);
 		break;
 	case XBOW_WIDGET_PART_NUM:
 	case XXBOW_WIDGET_PART_NUM:
+		pr_info("xtalk:n%d/0 xbow widget\n", nasid);
 		xbow_probe(nasid);
 		break;
 	default:
-		printk(" unknown widget??\n");
+		pr_info("xtalk:n%d/0 unknown widget (0x%x)\n", nasid, partnum);
 		break;
 	}
 }
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 6671946dbf66..c3815353f2f8 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -265,6 +265,9 @@  config PCIE_TANGO_SMP8759
 	  This can lead to data corruption if drivers perform concurrent
 	  config and MMIO accesses.
 
+config PCI_XTALK_BRIDGE
+	bool
+
 config VMD
 	depends on PCI_MSI && X86_64 && SRCU
 	tristate "Intel Volume Management Device Driver"
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index d56a507495c5..bcbd740f878c 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -28,6 +28,7 @@  obj-$(CONFIG_PCIE_ROCKCHIP_HOST) += pcie-rockchip-host.o
 obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
 obj-$(CONFIG_PCIE_MOBIVEIL) += pcie-mobiveil.o
 obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o
+obj-$(CONFIG_PCI_XTALK_BRIDGE) += pci-xtalk-bridge.o
 obj-$(CONFIG_VMD) += vmd.o
 # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
 obj-y				+= dwc/
diff --git a/arch/mips/pci/ops-bridge.c b/drivers/pci/controller/pci-xtalk-bridge.c
similarity index 52%
rename from arch/mips/pci/ops-bridge.c
rename to drivers/pci/controller/pci-xtalk-bridge.c
index df95b0da08f2..77e42c46937b 100644
--- a/arch/mips/pci/ops-bridge.c
+++ b/drivers/pci/controller/pci-xtalk-bridge.c
@@ -3,13 +3,21 @@ 
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (C) 1999, 2000, 04, 06 Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (C) 2003 Christoph Hellwig (hch@lst.de)
+ * Copyright (C) 1999, 2000, 04 Ralf Baechle (ralf@linux-mips.org)
  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  */
+#include <linux/kernel.h>
+#include <linux/export.h>
 #include <linux/pci.h>
-#include <asm/paccess.h>
-#include <asm/pci/bridge.h>
+#include <linux/smp.h>
+#include <linux/dma-direct.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/xtalk-bridge.h>
+
 #include <asm/sn/arch.h>
+#include <asm/pci/bridge.h>
+#include <asm/paccess.h>
 #include <asm/sn/intr.h>
 #include <asm/sn/sn0/hub.h>
 
@@ -29,6 +37,20 @@  static u32 emulate_ioc3_cfg(int where, int size)
 	return 0;
 }
 
+static void bridge_disable_swapping(struct pci_dev *dev)
+{
+	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
+	int slot = PCI_SLOT(dev->devfn);
+
+	/* Turn off byte swapping */
+	bridge_clr(bc, b_device[slot].reg, BRIDGE_DEV_SWAP_DIR);
+	bridge_read(bc, b_widget.w_tflush);	/* Flush */
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
+	bridge_disable_swapping);
+
+
 /*
  * The Bridge ASIC supports both type 0 and type 1 access.  Type 1 is
  * not really documented, so right now I can't write code which uses it.
@@ -39,20 +61,19 @@  static u32 emulate_ioc3_cfg(int where, int size)
  * which is used in SGI systems.  The IOC3 can only handle 32-bit PCI
  * accesses and does only decode parts of it's address space.
  */
-
 static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
-				 int where, int size, u32 * value)
+				 int where, int size, u32 *value)
 {
 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
 	struct bridge_regs *bridge = bc->base;
 	int slot = PCI_SLOT(devfn);
 	int fn = PCI_FUNC(devfn);
-	volatile void *addr;
+	void *addr;
 	u32 cf, shift, mask;
 	int res;
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	/*
@@ -65,11 +86,11 @@  static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
 
 	if (size == 1)
-		res = get_dbe(*value, (u8 *) addr);
+		res = get_dbe(*value, (u8 *)addr);
 	else if (size == 2)
-		res = get_dbe(*value, (u16 *) addr);
+		res = get_dbe(*value, (u16 *)addr);
 	else
-		res = get_dbe(*value, (u32 *) addr);
+		res = get_dbe(*value, (u32 *)addr);
 
 	return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
 
@@ -84,8 +105,7 @@  static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
 	}
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
-
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	shift = ((where & 3) << 3);
@@ -96,20 +116,20 @@  static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
 }
 
 static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
-				 int where, int size, u32 * value)
+				 int where, int size, u32 *value)
 {
 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
 	struct bridge_regs *bridge = bc->base;
 	int busno = bus->number;
 	int slot = PCI_SLOT(devfn);
 	int fn = PCI_FUNC(devfn);
-	volatile void *addr;
+	void *addr;
 	u32 cf, shift, mask;
 	int res;
 
 	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
 	addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	/*
@@ -119,15 +139,14 @@  static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
 	if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16)))
 		goto is_ioc3;
 
-	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
 	addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
 
 	if (size == 1)
-		res = get_dbe(*value, (u8 *) addr);
+		res = get_dbe(*value, (u8 *)addr);
 	else if (size == 2)
-		res = get_dbe(*value, (u16 *) addr);
+		res = get_dbe(*value, (u16 *)addr);
 	else
-		res = get_dbe(*value, (u32 *) addr);
+		res = get_dbe(*value, (u32 *)addr);
 
 	return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
 
@@ -141,10 +160,8 @@  static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
 		return PCIBIOS_SUCCESSFUL;
 	}
 
-	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
 	addr = &bridge->b_type1_cfg.c[(fn << 8) | where];
-
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	shift = ((where & 3) << 3);
@@ -155,7 +172,7 @@  static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
 }
 
 static int pci_read_config(struct pci_bus *bus, unsigned int devfn,
-			   int where, int size, u32 * value)
+			   int where, int size, u32 *value)
 {
 	if (!pci_is_root_bus(bus))
 		return pci_conf1_read_config(bus, devfn, where, size, value);
@@ -170,12 +187,12 @@  static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
 	struct bridge_regs *bridge = bc->base;
 	int slot = PCI_SLOT(devfn);
 	int fn = PCI_FUNC(devfn);
-	volatile void *addr;
+	void *addr;
 	u32 cf, shift, mask, smask;
 	int res;
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	/*
@@ -187,13 +204,12 @@  static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
 
-	if (size == 1) {
-		res = put_dbe(value, (u8 *) addr);
-	} else if (size == 2) {
-		res = put_dbe(value, (u16 *) addr);
-	} else {
-		res = put_dbe(value, (u32 *) addr);
-	}
+	if (size == 1)
+		res = put_dbe(value, (u8 *)addr);
+	else if (size == 2)
+		res = put_dbe(value, (u16 *)addr);
+	else
+		res = put_dbe(value, (u32 *)addr);
 
 	if (res)
 		return PCIBIOS_DEVICE_NOT_FOUND;
@@ -210,7 +226,7 @@  static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
 
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	shift = ((where & 3) << 3);
@@ -218,7 +234,7 @@  static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
 	smask = mask << shift;
 
 	cf = (cf & ~smask) | ((value & mask) << shift);
-	if (put_dbe(cf, (u32 *) addr))
+	if (put_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	return PCIBIOS_SUCCESSFUL;
@@ -232,13 +248,13 @@  static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
 	int slot = PCI_SLOT(devfn);
 	int fn = PCI_FUNC(devfn);
 	int busno = bus->number;
-	volatile void *addr;
+	void *addr;
 	u32 cf, shift, mask, smask;
 	int res;
 
 	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
 	addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	/*
@@ -250,13 +266,12 @@  static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
 
 	addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
 
-	if (size == 1) {
-		res = put_dbe(value, (u8 *) addr);
-	} else if (size == 2) {
-		res = put_dbe(value, (u16 *) addr);
-	} else {
-		res = put_dbe(value, (u32 *) addr);
-	}
+	if (size == 1)
+		res = put_dbe(value, (u8 *)addr);
+	else if (size == 2)
+		res = put_dbe(value, (u16 *)addr);
+	else
+		res = put_dbe(value, (u32 *)addr);
 
 	if (res)
 		return PCIBIOS_DEVICE_NOT_FOUND;
@@ -272,8 +287,7 @@  static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
 		return PCIBIOS_SUCCESSFUL;
 
 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
-
-	if (get_dbe(cf, (u32 *) addr))
+	if (get_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	shift = ((where & 3) << 3);
@@ -281,7 +295,7 @@  static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
 	smask = mask << shift;
 
 	cf = (cf & ~smask) | ((value & mask) << shift);
-	if (put_dbe(cf, (u32 *) addr))
+	if (put_dbe(cf, (u32 *)addr))
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
 	return PCIBIOS_SUCCESSFUL;
@@ -296,7 +310,173 @@  static int pci_write_config(struct pci_bus *bus, unsigned int devfn,
 	return pci_conf0_write_config(bus, devfn, where, size, value);
 }
 
-struct pci_ops bridge_pci_ops = {
-	.read	= pci_read_config,
-	.write	= pci_write_config,
+static int bridge_add_bus(struct pci_bus *bus)
+{
+	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
+
+	set_dev_node(&bus->dev, bc->nasid);
+	return 0;
+}
+
+static struct pci_ops bridge_pci_ops = {
+	.add_bus = bridge_add_bus,
+	.read	 = pci_read_config,
+	.write	 = pci_write_config,
+};
+
+/*
+ * All observed requests have pin == 1. We could have a global here, that
+ * gets incremented and returned every time - unfortunately, pci_map_irq
+ * may be called on the same device over and over, and need to return the
+ * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
+ *
+ * A given PCI device, in general, should be able to intr any of the cpus
+ * on any one of the hubs connected to its xbow.
+ */
+static int bridge_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
+	int irq;
+
+	irq = bc->pci_int[slot];
+	if (irq == -1) {
+		irq = request_bridge_irq(bc, slot);
+		if (irq < 0)
+			return irq;
+
+		bc->pci_int[slot] = irq;
+	}
+	return irq;
+}
+
+static int bridge_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct bridge_controller *bc;
+	struct pci_host_bridge *host;
+	unsigned long offset;
+	int slot;
+	int err;
+	struct xtalk_bridge_platform_data *bd = dev_get_platdata(&pdev->dev);
+
+	offset = NODE_OFFSET(bd->nasid);
+
+	pci_set_flags(PCI_PROBE_ONLY);
+
+	host = devm_pci_alloc_host_bridge(dev, sizeof(*bc));
+	if (!host)
+		return -ENOMEM;
+
+	bc = pci_host_bridge_priv(host);
+
+	bc->mem.name		= "Bridge PCI MEM";
+	bc->mem.start		= offset + (bd->widget << SWIN_SIZE_BITS);
+	bc->mem.end		= bc->mem.start + SWIN_SIZE;
+	bc->mem.flags		= IORESOURCE_MEM;
+
+	bc->io.name		= "Bridge PCI IO";
+	bc->io.start		= offset + (bd->widget << SWIN_SIZE_BITS);
+	bc->io.end		= bc->io.start + SWIN_SIZE;
+	bc->io.flags		= IORESOURCE_IO;
+
+	bc->busn.name		= "Bridge PCI busn";
+	bc->busn.start		= 0;
+	bc->busn.end		= 0xff;
+	bc->busn.flags		= IORESOURCE_BUS;
+
+	pci_add_resource_offset(&host->windows, &bc->mem, offset);
+	pci_add_resource_offset(&host->windows, &bc->io, offset);
+	pci_add_resource(&host->windows, &bc->busn);
+
+	err = devm_request_pci_bus_resources(dev, &host->windows);
+	if (err < 0) {
+		pci_free_resource_list(&host->windows);
+		return err;
+	}
+
+	bc->nasid = bd->nasid;
+
+	bc->baddr = (u64)bd->masterwid << 60 | PCI64_ATTR_BAR;
+
+	/*
+	 * point to this bridge
+	 */
+	bc->base = (struct bridge_regs *)RAW_NODE_SWIN_BASE(bd->nasid,
+							    bd->widget);
+
+	/*
+	 * Clear all pending interrupts.
+	 */
+	bridge_write(bc, b_int_rst_stat, BRIDGE_IRR_ALL_CLR);
+
+	/*
+	 * Until otherwise set up, assume all interrupts are from slot 0
+	 */
+	bridge_write(bc, b_int_device, 0x0);
+
+	/*
+	 * disable swapping for big windows
+	 */
+	bridge_clr(bc, b_wid_control,
+		   BRIDGE_CTRL_IO_SWAP | BRIDGE_CTRL_MEM_SWAP);
+#ifdef CONFIG_PAGE_SIZE_4KB
+	bridge_clr(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
+#else /* 16kB or larger */
+	bridge_set(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
+#endif
+
+	/*
+	 * Hmm...  IRIX sets additional bits in the address which
+	 * are documented as reserved in the bridge docs.
+	 */
+	bridge_write(bc, b_wid_int_upper, 0x8000 | (bd->masterwid << 16));
+	bridge_write(bc, b_wid_int_lower, 0x01800090);	/* PI_INT_PEND_MOD off*/
+	bridge_write(bc, b_dir_map, (bd->masterwid << 20));	/* DMA */
+	bridge_write(bc, b_int_enable, 0);
+
+	for (slot = 0; slot < 8; slot++) {
+		bridge_set(bc, b_device[slot].reg, BRIDGE_DEV_SWAP_DIR);
+		bc->pci_int[slot] = -1;
+	}
+	bridge_read(bc, b_wid_tflush);	  /* wait until Bridge PIO complete */
+
+	host->dev.parent = dev;
+	host->sysdata = bc;
+	host->busnr = 0;
+	host->ops = &bridge_pci_ops;
+	host->map_irq = bridge_map_irq;
+	host->swizzle_irq = pci_common_swizzle;
+
+	err = pci_scan_root_bus_bridge(host);
+	if (err < 0)
+		return err;
+
+	pci_bus_claim_resources(host->bus);
+	pci_bus_add_devices(host->bus);
+
+	platform_set_drvdata(pdev, host->bus);
+
+	return 0;
+}
+
+static int bridge_remove(struct platform_device *pdev)
+{
+	struct pci_bus *bus = platform_get_drvdata(pdev);
+
+	pci_lock_rescan_remove();
+	pci_stop_root_bus(bus);
+	pci_remove_root_bus(bus);
+	pci_unlock_rescan_remove();
+
+	return 0;
+}
+
+static struct platform_driver bridge_driver = {
+	.probe  = bridge_probe,
+	.remove = bridge_remove,
+	.driver = {
+		.name = "xtalk-bridge",
+	}
 };
+
+builtin_platform_driver(bridge_driver);
diff --git a/include/linux/platform_data/xtalk-bridge.h b/include/linux/platform_data/xtalk-bridge.h
new file mode 100644
index 000000000000..818d4b457429
--- /dev/null
+++ b/include/linux/platform_data/xtalk-bridge.h
@@ -0,0 +1,17 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * SGI PCI Xtalk Bridge
+ */
+
+#ifndef PLATFORM_DATA_XTALK_BRIDGE_H
+#define PLATFORM_DATA_XTALK_BRIDGE_H
+
+#include <asm/sn/types.h>
+
+struct xtalk_bridge_platform_data {
+	nasid_t	nasid;
+	int	widget;
+	int	masterwid;
+};
+
+#endif /* PLATFORM_DATA_XTALK_BRIDGE_H */