arch/powerpc/kernel/rtas_pci.c - linux - Git at Google

 /*
  * 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 <linux/bootmem.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;

 	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;

 	if (returnval == EEH_IO_ERROR_VALUE(size) &&
 	    eeh_dn_check_failure (pdn->node, NULL))
 		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 device_node *busdn, *dn;

 	if (bus->self)
 		busdn = pci_device_to_OF_node(bus->self);
 	else
 		busdn = bus->sysdata;	/* must be a phb */

 	/* Search only direct children of the bus */
 	for (dn = busdn->child; dn; dn = dn->sibling) {
 		struct pci_dn *pdn = PCI_DN(dn);
 		if (pdn && pdn->devfn == devfn
 		    && of_device_is_available(dn))
 			return rtas_read_config(pdn, where, size, val);
 	}

 	return PCIBIOS_DEVICE_NOT_FOUND;
 }

 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;

 	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 device_node *busdn, *dn;

 	if (bus->self)
 		busdn = pci_device_to_OF_node(bus->self);
 	else
 		busdn = bus->sysdata;	/* must be a phb */

 	/* Search only direct children of the bus */
 	for (dn = busdn->child; dn; dn = dn->sibling) {
 		struct pci_dn *pdn = PCI_DN(dn);
 		if (pdn && pdn->devfn == devfn
 		    && of_device_is_available(dn))
 			return rtas_write_config(pdn, where, size, val);
 	}
 	return PCIBIOS_DEVICE_NOT_FOUND;
 }

 struct pci_ops rtas_pci_ops = {
 	.read = rtas_pci_read_config,
 	.write = rtas_pci_write_config,
 };

 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 __devinit 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 int *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 =  bus_range[0];
 	phb->last_busno  =  bus_range[1];

 	return 0;
 }

 int __devinit 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;
 }

 void __init find_and_init_phbs(void)
 {
 	struct device_node *node;
 	struct pci_controller *phb;
 	struct device_node *root = of_find_node_by_path("/");

 	for_each_child_of_node(root, node) {
 		if (node->type == NULL || (strcmp(node->type, "pci") != 0 &&
 					   strcmp(node->type, "pciex") != 0))
 			continue;

 		phb = pcibios_alloc_controller(node);
 		if (!phb)
 			continue;
 		rtas_setup_phb(phb);
 		pci_process_bridge_OF_ranges(phb, node, 0);
 		isa_bridge_find_early(phb);
 	}

 	of_node_put(root);
 	pci_devs_phb_init();

 	/*
 	 * pci_probe_only and pci_assign_all_buses can be set via properties
 	 * in chosen.
 	 */
 	if (of_chosen) {
 		const int *prop;

 		prop = of_get_property(of_chosen,
 				"linux,pci-probe-only", NULL);
 		if (prop)
 			pci_probe_only = *prop;

 #ifdef CONFIG_PPC32 /* Will be made generic soon */
 		prop = of_get_property(of_chosen,
 				"linux,pci-assign-all-buses", NULL);
 		if (prop && *prop)
 			ppc_pci_flags |= PPC_PCI_REASSIGN_ALL_BUS;
 #endif /* CONFIG_PPC32 */
 	}
 }

 /* RPA-specific bits for removing PHBs */
 int pcibios_remove_root_bus(struct pci_controller *phb)
 {
 	struct pci_bus *b = phb->bus;
 	struct resource *res;
 	int rc, i;

 	res = b->resource[0];
 	if (!res->flags) {
 		printk(KERN_ERR "%s: no IO resource for PHB %s\n", __func__,
 				b->name);
 		return 1;
 	}

 	rc = pcibios_unmap_io_space(b);
 	if (rc) {
 		printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 			__func__, b->name);
 		return 1;
 	}

 	if (release_resource(res)) {
 		printk(KERN_ERR "%s: failed to release IO on bus %s\n",
 				__func__, b->name);
 		return 1;
 	}

 	for (i = 1; i < 3; ++i) {
 		res = b->resource[i];
 		if (!res->flags && i == 0) {
 			printk(KERN_ERR "%s: no MEM resource for PHB %s\n",
 				__func__, b->name);
 			return 1;
 		}
 		if (res->flags && release_resource(res)) {
 			printk(KERN_ERR
 			       "%s: failed to release IO %d on bus %s\n",
 				__func__, i, b->name);
 			return 1;
 		}
 	}

 	pcibios_free_controller(phb);

 	return 0;
 }
 EXPORT_SYMBOL(pcibios_remove_root_bus);
	/*
	* 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 <linux/bootmem.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;

	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;

	if (returnval == EEH_IO_ERROR_VALUE(size) &&
	eeh_dn_check_failure (pdn->node, NULL))
	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 device_node busdn, dn;

	if (bus->self)
	busdn = pci_device_to_OF_node(bus->self);
	else
	busdn = bus->sysdata; /* must be a phb */

	/* Search only direct children of the bus */
	for (dn = busdn->child; dn; dn = dn->sibling) {
	struct pci_dn *pdn = PCI_DN(dn);
	if (pdn && pdn->devfn == devfn
	&& of_device_is_available(dn))
	return rtas_read_config(pdn, where, size, val);
	}

	return PCIBIOS_DEVICE_NOT_FOUND;
	}

	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;

	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 device_node busdn, dn;

	if (bus->self)
	busdn = pci_device_to_OF_node(bus->self);
	else
	busdn = bus->sysdata; /* must be a phb */

	/* Search only direct children of the bus */
	for (dn = busdn->child; dn; dn = dn->sibling) {
	struct pci_dn *pdn = PCI_DN(dn);
	if (pdn && pdn->devfn == devfn
	&& of_device_is_available(dn))
	return rtas_write_config(pdn, where, size, val);
	}
	return PCIBIOS_DEVICE_NOT_FOUND;
	}

	struct pci_ops rtas_pci_ops = {
	.read = rtas_pci_read_config,
	.write = rtas_pci_write_config,
	};

	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 __devinit 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 int *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 = bus_range[0];
	phb->last_busno = bus_range[1];

	return 0;
	}

	int __devinit 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;
	}

	void __init find_and_init_phbs(void)
	{
	struct device_node *node;
	struct pci_controller *phb;
	struct device_node *root = of_find_node_by_path("/");

	for_each_child_of_node(root, node) {
	if (node->type == NULL \|\| (strcmp(node->type, "pci") != 0 &&
	strcmp(node->type, "pciex") != 0))
	continue;

	phb = pcibios_alloc_controller(node);
	if (!phb)
	continue;
	rtas_setup_phb(phb);
	pci_process_bridge_OF_ranges(phb, node, 0);
	isa_bridge_find_early(phb);
	}

	of_node_put(root);
	pci_devs_phb_init();

	/*
	* pci_probe_only and pci_assign_all_buses can be set via properties
	* in chosen.
	*/
	if (of_chosen) {
	const int *prop;

	prop = of_get_property(of_chosen,
	"linux,pci-probe-only", NULL);
	if (prop)
	pci_probe_only = *prop;

	#ifdef CONFIG_PPC32 /* Will be made generic soon */
	prop = of_get_property(of_chosen,
	"linux,pci-assign-all-buses", NULL);
	if (prop && *prop)
	ppc_pci_flags \|= PPC_PCI_REASSIGN_ALL_BUS;
	#endif /* CONFIG_PPC32 */
	}
	}

	/* RPA-specific bits for removing PHBs */
	int pcibios_remove_root_bus(struct pci_controller *phb)
	{
	struct pci_bus *b = phb->bus;
	struct resource *res;
	int rc, i;

	res = b->resource[0];
	if (!res->flags) {
	printk(KERN_ERR "%s: no IO resource for PHB %s\n", __func__,
	b->name);
	return 1;
	}

	rc = pcibios_unmap_io_space(b);
	if (rc) {
	printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
	__func__, b->name);
	return 1;
	}

	if (release_resource(res)) {
	printk(KERN_ERR "%s: failed to release IO on bus %s\n",
	__func__, b->name);
	return 1;
	}

	for (i = 1; i < 3; ++i) {
	res = b->resource[i];
	if (!res->flags && i == 0) {
	printk(KERN_ERR "%s: no MEM resource for PHB %s\n",
	__func__, b->name);
	return 1;
	}
	if (res->flags && release_resource(res)) {
	printk(KERN_ERR
	"%s: failed to release IO %d on bus %s\n",
	__func__, i, b->name);
	return 1;
	}
	}

	pcibios_free_controller(phb);

	return 0;
	}
	EXPORT_SYMBOL(pcibios_remove_root_bus);