v4.19.13 snapshot.
diff --git a/arch/powerpc/kernel/rtas_pci.c b/arch/powerpc/kernel/rtas_pci.c
new file mode 100644
index 0000000..c2b148b
--- /dev/null
+++ b/arch/powerpc/kernel/rtas_pci.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright (C) 2001 Dave Engebretsen, IBM Corporation
+ * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * RTAS specific routines for PCI.
+ *
+ * Based on code from pci.c, chrp_pci.c and pSeries_pci.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/threads.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/pci-bridge.h>
+#include <asm/iommu.h>
+#include <asm/rtas.h>
+#include <asm/mpic.h>
+#include <asm/ppc-pci.h>
+#include <asm/eeh.h>
+
+/* RTAS tokens */
+static int read_pci_config;
+static int write_pci_config;
+static int ibm_read_pci_config;
+static int ibm_write_pci_config;
+
+static inline int config_access_valid(struct pci_dn *dn, int where)
+{
+	if (where < 256)
+		return 1;
+	if (where < 4096 && dn->pci_ext_config_space)
+		return 1;
+
+	return 0;
+}
+
+int rtas_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
+{
+	int returnval = -1;
+	unsigned long buid, addr;
+	int ret;
+
+	if (!pdn)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	if (!config_access_valid(pdn, where))
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+#ifdef CONFIG_EEH
+	if (pdn->edev && pdn->edev->pe &&
+	    (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
+		return PCIBIOS_SET_FAILED;
+#endif
+
+	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
+	buid = pdn->phb->buid;
+	if (buid) {
+		ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
+				addr, BUID_HI(buid), BUID_LO(buid), size);
+	} else {
+		ret = rtas_call(read_pci_config, 2, 2, &returnval, addr, size);
+	}
+	*val = returnval;
+
+	if (ret)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int rtas_pci_read_config(struct pci_bus *bus,
+				unsigned int devfn,
+				int where, int size, u32 *val)
+{
+	struct pci_dn *pdn;
+	int ret;
+
+	*val = 0xFFFFFFFF;
+
+	pdn = pci_get_pdn_by_devfn(bus, devfn);
+
+	/* Validity of pdn is checked in here */
+	ret = rtas_read_config(pdn, where, size, val);
+	if (*val == EEH_IO_ERROR_VALUE(size) &&
+	    eeh_dev_check_failure(pdn_to_eeh_dev(pdn)))
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	return ret;
+}
+
+int rtas_write_config(struct pci_dn *pdn, int where, int size, u32 val)
+{
+	unsigned long buid, addr;
+	int ret;
+
+	if (!pdn)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	if (!config_access_valid(pdn, where))
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+#ifdef CONFIG_EEH
+	if (pdn->edev && pdn->edev->pe &&
+	    (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
+		return PCIBIOS_SET_FAILED;
+#endif
+
+	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
+	buid = pdn->phb->buid;
+	if (buid) {
+		ret = rtas_call(ibm_write_pci_config, 5, 1, NULL, addr,
+			BUID_HI(buid), BUID_LO(buid), size, (ulong) val);
+	} else {
+		ret = rtas_call(write_pci_config, 3, 1, NULL, addr, size, (ulong)val);
+	}
+
+	if (ret)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int rtas_pci_write_config(struct pci_bus *bus,
+				 unsigned int devfn,
+				 int where, int size, u32 val)
+{
+	struct pci_dn *pdn;
+
+	pdn = pci_get_pdn_by_devfn(bus, devfn);
+
+	/* Validity of pdn is checked in here. */
+	return rtas_write_config(pdn, where, size, val);
+}
+
+static struct pci_ops rtas_pci_ops = {
+	.read = rtas_pci_read_config,
+	.write = rtas_pci_write_config,
+};
+
+static int is_python(struct device_node *dev)
+{
+	const char *model = of_get_property(dev, "model", NULL);
+
+	if (model && strstr(model, "Python"))
+		return 1;
+
+	return 0;
+}
+
+static void python_countermeasures(struct device_node *dev)
+{
+	struct resource registers;
+	void __iomem *chip_regs;
+	volatile u32 val;
+
+	if (of_address_to_resource(dev, 0, &registers)) {
+		printk(KERN_ERR "Can't get address for Python workarounds !\n");
+		return;
+	}
+
+	/* Python's register file is 1 MB in size. */
+	chip_regs = ioremap(registers.start & ~(0xfffffUL), 0x100000);
+
+	/*
+	 * Firmware doesn't always clear this bit which is critical
+	 * for good performance - Anton
+	 */
+
+#define PRG_CL_RESET_VALID 0x00010000
+
+	val = in_be32(chip_regs + 0xf6030);
+	if (val & PRG_CL_RESET_VALID) {
+		printk(KERN_INFO "Python workaround: ");
+		val &= ~PRG_CL_RESET_VALID;
+		out_be32(chip_regs + 0xf6030, val);
+		/*
+		 * We must read it back for changes to
+		 * take effect
+		 */
+		val = in_be32(chip_regs + 0xf6030);
+		printk("reg0: %x\n", val);
+	}
+
+	iounmap(chip_regs);
+}
+
+void __init init_pci_config_tokens(void)
+{
+	read_pci_config = rtas_token("read-pci-config");
+	write_pci_config = rtas_token("write-pci-config");
+	ibm_read_pci_config = rtas_token("ibm,read-pci-config");
+	ibm_write_pci_config = rtas_token("ibm,write-pci-config");
+}
+
+unsigned long get_phb_buid(struct device_node *phb)
+{
+	struct resource r;
+
+	if (ibm_read_pci_config == -1)
+		return 0;
+	if (of_address_to_resource(phb, 0, &r))
+		return 0;
+	return r.start;
+}
+
+static int phb_set_bus_ranges(struct device_node *dev,
+			      struct pci_controller *phb)
+{
+	const __be32 *bus_range;
+	unsigned int len;
+
+	bus_range = of_get_property(dev, "bus-range", &len);
+	if (bus_range == NULL || len < 2 * sizeof(int)) {
+		return 1;
+ 	}
+
+	phb->first_busno = be32_to_cpu(bus_range[0]);
+	phb->last_busno  = be32_to_cpu(bus_range[1]);
+
+	return 0;
+}
+
+int rtas_setup_phb(struct pci_controller *phb)
+{
+	struct device_node *dev = phb->dn;
+
+	if (is_python(dev))
+		python_countermeasures(dev);
+
+	if (phb_set_bus_ranges(dev, phb))
+		return 1;
+
+	phb->ops = &rtas_pci_ops;
+	phb->buid = get_phb_buid(dev);
+
+	return 0;
+}