File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/mips/pci/ops-lantiq.c b/arch/mips/pci/ops-lantiq.c
new file mode 100644
index 0000000..e5738ee
--- /dev/null
+++ b/arch/mips/pci/ops-lantiq.c
@@ -0,0 +1,115 @@
+/*
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ *
+ *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/mm.h>
+#include <asm/addrspace.h>
+#include <linux/vmalloc.h>
+
+#include <lantiq_soc.h>
+
+#include "pci-lantiq.h"
+
+#define LTQ_PCI_CFG_BUSNUM_SHF 16
+#define LTQ_PCI_CFG_DEVNUM_SHF 11
+#define LTQ_PCI_CFG_FUNNUM_SHF 8
+
+#define PCI_ACCESS_READ	 0
+#define PCI_ACCESS_WRITE 1
+
+static int ltq_pci_config_access(unsigned char access_type, struct pci_bus *bus,
+	unsigned int devfn, unsigned int where, u32 *data)
+{
+	unsigned long cfg_base;
+	unsigned long flags;
+	u32 temp;
+
+	/* we support slot from 0 to 15 dev_fn & 0x68 (AD29) is the
+	   SoC itself */
+	if ((bus->number != 0) || ((devfn & 0xf8) > 0x78)
+		|| ((devfn & 0xf8) == 0) || ((devfn & 0xf8) == 0x68))
+		return 1;
+
+	spin_lock_irqsave(&ebu_lock, flags);
+
+	cfg_base = (unsigned long) ltq_pci_mapped_cfg;
+	cfg_base |= (bus->number << LTQ_PCI_CFG_BUSNUM_SHF) | (devfn <<
+			LTQ_PCI_CFG_FUNNUM_SHF) | (where & ~0x3);
+
+	/* Perform access */
+	if (access_type == PCI_ACCESS_WRITE) {
+		ltq_w32(swab32(*data), ((u32 *)cfg_base));
+	} else {
+		*data = ltq_r32(((u32 *)(cfg_base)));
+		*data = swab32(*data);
+	}
+	wmb();
+
+	/* clean possible Master abort */
+	cfg_base = (unsigned long) ltq_pci_mapped_cfg;
+	cfg_base |= (0x0 << LTQ_PCI_CFG_FUNNUM_SHF) + 4;
+	temp = ltq_r32(((u32 *)(cfg_base)));
+	temp = swab32(temp);
+	cfg_base = (unsigned long) ltq_pci_mapped_cfg;
+	cfg_base |= (0x68 << LTQ_PCI_CFG_FUNNUM_SHF) + 4;
+	ltq_w32(temp, ((u32 *)cfg_base));
+
+	spin_unlock_irqrestore(&ebu_lock, flags);
+
+	if (((*data) == 0xffffffff) && (access_type == PCI_ACCESS_READ))
+		return 1;
+
+	return 0;
+}
+
+int ltq_pci_read_config_dword(struct pci_bus *bus, unsigned int devfn,
+	int where, int size, u32 *val)
+{
+	u32 data = 0;
+
+	if (ltq_pci_config_access(PCI_ACCESS_READ, bus, devfn, where, &data))
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	if (size == 1)
+		*val = (data >> ((where & 3) << 3)) & 0xff;
+	else if (size == 2)
+		*val = (data >> ((where & 3) << 3)) & 0xffff;
+	else
+		*val = data;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+int ltq_pci_write_config_dword(struct pci_bus *bus, unsigned int devfn,
+	int where, int size, u32 val)
+{
+	u32 data = 0;
+
+	if (size == 4) {
+		data = val;
+	} else {
+		if (ltq_pci_config_access(PCI_ACCESS_READ, bus,
+				devfn, where, &data))
+			return PCIBIOS_DEVICE_NOT_FOUND;
+
+		if (size == 1)
+			data = (data & ~(0xff << ((where & 3) << 3))) |
+				(val << ((where & 3) << 3));
+		else if (size == 2)
+			data = (data & ~(0xffff << ((where & 3) << 3))) |
+				(val << ((where & 3) << 3));
+	}
+
+	if (ltq_pci_config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data))
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	return PCIBIOS_SUCCESSFUL;
+}