drivers/bcma/driver_pci_host.c - kernel/msm-4.9 - Gitiles

 /*
  * Broadcom specific AMBA
  * PCI Core in hostmode
  *
  * Copyright 2005 - 2011, Broadcom Corporation
  * Copyright 2006, 2007, Michael Buesch <m@bues.ch>
  * Copyright 2011, 2012, Hauke Mehrtens <hauke@hauke-m.de>
  *
  * Licensed under the GNU/GPL. See COPYING for details.
  */

 #include "bcma_private.h"
 #include <linux/pci.h>
 #include <linux/export.h>
 #include <linux/bcma/bcma.h>
 #include <asm/paccess.h>

 /* Probe a 32bit value on the bus and catch bus exceptions.
  * Returns nonzero on a bus exception.
  * This is MIPS specific */
 #define mips_busprobe32(val, addr)	get_dbe((val), ((u32 *)(addr)))

 /* Assume one-hot slot wiring */
 #define BCMA_PCI_SLOT_MAX	16
 #define	PCI_CONFIG_SPACE_SIZE	256

 bool __devinit bcma_core_pci_is_in_hostmode(struct bcma_drv_pci *pc)
 {
 	struct bcma_bus *bus = pc->core->bus;
 	u16 chipid_top;
 	u32 tmp;

 	chipid_top = (bus->chipinfo.id & 0xFF00);
 	if (chipid_top != 0x4700 &&
 	    chipid_top != 0x5300)
 		return false;

 	bcma_core_enable(pc->core, 0);

 	return !mips_busprobe32(tmp, pc->core->io_addr);
 }

 static u32 bcma_pcie_read_config(struct bcma_drv_pci *pc, u32 address)
 {
 	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
 	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
 	return pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_DATA);
 }

 static void bcma_pcie_write_config(struct bcma_drv_pci *pc, u32 address,
 				   u32 data)
 {
 	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
 	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
 	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_DATA, data);
 }

 static u32 bcma_get_cfgspace_addr(struct bcma_drv_pci *pc, unsigned int dev,
 			     unsigned int func, unsigned int off)
 {
 	u32 addr = 0;

 	/* Issue config commands only when the data link is up (atleast
 	 * one external pcie device is present).
 	 */
 	if (dev >= 2 || !(bcma_pcie_read(pc, BCMA_CORE_PCI_DLLP_LSREG)
 			  & BCMA_CORE_PCI_DLLP_LSREG_LINKUP))
 		goto out;

 	/* Type 0 transaction */
 	/* Slide the PCI window to the appropriate slot */
 	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);
 	/* Calculate the address */
 	addr = pc->host_controller->host_cfg_addr;
 	addr |= (dev << BCMA_CORE_PCI_CFG_SLOT_SHIFT);
 	addr |= (func << BCMA_CORE_PCI_CFG_FUN_SHIFT);
 	addr |= (off & ~3);

 out:
 	return addr;
 }

 static int bcma_extpci_read_config(struct bcma_drv_pci *pc, unsigned int dev,
 				  unsigned int func, unsigned int off,
 				  void *buf, int len)
 {
 	int err = -EINVAL;
 	u32 addr, val;
 	void __iomem *mmio = 0;

 	WARN_ON(!pc->hostmode);
 	if (unlikely(len != 1 && len != 2 && len != 4))
 		goto out;
 	if (dev == 0) {
 		/* we support only two functions on device 0 */
 		if (func > 1)
 			return -EINVAL;

 		/* accesses to config registers with offsets >= 256
 		 * requires indirect access.
 		 */
 		if (off >= PCI_CONFIG_SPACE_SIZE) {
 			addr = (func << 12);
 			addr |= (off & 0x0FFF);
 			val = bcma_pcie_read_config(pc, addr);
 		} else {
 			addr = BCMA_CORE_PCI_PCICFG0;
 			addr |= (func << 8);
 			addr |= (off & 0xfc);
 			val = pcicore_read32(pc, addr);
 		}
 	} else {
 		addr = bcma_get_cfgspace_addr(pc, dev, func, off);
 		if (unlikely(!addr))
 			goto out;
 		err = -ENOMEM;
 		mmio = ioremap_nocache(addr, sizeof(val));
 		if (!mmio)
 			goto out;

 		if (mips_busprobe32(val, mmio)) {
 			val = 0xffffffff;
 			goto unmap;
 		}

 		val = readl(mmio);
 	}
 	val >>= (8 * (off & 3));

 	switch (len) {
 	case 1:
 		*((u8 *)buf) = (u8)val;
 		break;
 	case 2:
 		*((u16 *)buf) = (u16)val;
 		break;
 	case 4:
 		*((u32 *)buf) = (u32)val;
 		break;
 	}
 	err = 0;
 unmap:
 	if (mmio)
 		iounmap(mmio);
 out:
 	return err;
 }

 static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
 				   unsigned int func, unsigned int off,
 				   const void *buf, int len)
 {
 	int err = -EINVAL;
 	u32 addr = 0, val = 0;
 	void __iomem *mmio = 0;
 	u16 chipid = pc->core->bus->chipinfo.id;

 	WARN_ON(!pc->hostmode);
 	if (unlikely(len != 1 && len != 2 && len != 4))
 		goto out;
 	if (dev == 0) {
 		/* accesses to config registers with offsets >= 256
 		 * requires indirect access.
 		 */
 		if (off < PCI_CONFIG_SPACE_SIZE) {
 			addr = pc->core->addr + BCMA_CORE_PCI_PCICFG0;
 			addr |= (func << 8);
 			addr |= (off & 0xfc);
 			mmio = ioremap_nocache(addr, sizeof(val));
 			if (!mmio)
 				goto out;
 		}
 	} else {
 		addr = bcma_get_cfgspace_addr(pc, dev, func, off);
 		if (unlikely(!addr))
 			goto out;
 		err = -ENOMEM;
 		mmio = ioremap_nocache(addr, sizeof(val));
 		if (!mmio)
 			goto out;

 		if (mips_busprobe32(val, mmio)) {
 			val = 0xffffffff;
 			goto unmap;
 		}
 	}

 	switch (len) {
 	case 1:
 		val = readl(mmio);
 		val &= ~(0xFF << (8 * (off & 3)));
 		val |= *((const u8 *)buf) << (8 * (off & 3));
 		break;
 	case 2:
 		val = readl(mmio);
 		val &= ~(0xFFFF << (8 * (off & 3)));
 		val |= *((const u16 *)buf) << (8 * (off & 3));
 		break;
 	case 4:
 		val = *((const u32 *)buf);
 		break;
 	}
 	if (dev == 0 && !addr) {
 		/* accesses to config registers with offsets >= 256
 		 * requires indirect access.
 		 */
 		addr = (func << 12);
 		addr |= (off & 0x0FFF);
 		bcma_pcie_write_config(pc, addr, val);
 	} else {
 		writel(val, mmio);

 		if (chipid == BCMA_CHIP_ID_BCM4716 ||
 		    chipid == BCMA_CHIP_ID_BCM4748)
 			readl(mmio);
 	}

 	err = 0;
 unmap:
 	if (mmio)
 		iounmap(mmio);
 out:
 	return err;
 }

 static int bcma_core_pci_hostmode_read_config(struct pci_bus *bus,
 					      unsigned int devfn,
 					      int reg, int size, u32 *val)
 {
 	unsigned long flags;
 	int err;
 	struct bcma_drv_pci *pc;
 	struct bcma_drv_pci_host *pc_host;

 	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
 	pc = pc_host->pdev;

 	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
 	err = bcma_extpci_read_config(pc, PCI_SLOT(devfn),
 				     PCI_FUNC(devfn), reg, val, size);
 	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);

 	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
 }

 static int bcma_core_pci_hostmode_write_config(struct pci_bus *bus,
 					       unsigned int devfn,
 					       int reg, int size, u32 val)
 {
 	unsigned long flags;
 	int err;
 	struct bcma_drv_pci *pc;
 	struct bcma_drv_pci_host *pc_host;

 	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
 	pc = pc_host->pdev;

 	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
 	err = bcma_extpci_write_config(pc, PCI_SLOT(devfn),
 				      PCI_FUNC(devfn), reg, &val, size);
 	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);

 	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
 }

 /* return cap_offset if requested capability exists in the PCI config space */
 static u8 __devinit bcma_find_pci_capability(struct bcma_drv_pci *pc,
 					     unsigned int dev,
 					     unsigned int func, u8 req_cap_id,
 					     unsigned char *buf, u32 *buflen)
 {
 	u8 cap_id;
 	u8 cap_ptr = 0;
 	u32 bufsize;
 	u8 byte_val;

 	/* check for Header type 0 */
 	bcma_extpci_read_config(pc, dev, func, PCI_HEADER_TYPE, &byte_val,
 				sizeof(u8));
 	if ((byte_val & 0x7f) != PCI_HEADER_TYPE_NORMAL)
 		return cap_ptr;

 	/* check if the capability pointer field exists */
 	bcma_extpci_read_config(pc, dev, func, PCI_STATUS, &byte_val,
 				sizeof(u8));
 	if (!(byte_val & PCI_STATUS_CAP_LIST))
 		return cap_ptr;

 	/* check if the capability pointer is 0x00 */
 	bcma_extpci_read_config(pc, dev, func, PCI_CAPABILITY_LIST, &cap_ptr,
 				sizeof(u8));
 	if (cap_ptr == 0x00)
 		return cap_ptr;

 	/* loop thr'u the capability list and see if the requested capabilty
 	 * exists */
 	bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id, sizeof(u8));
 	while (cap_id != req_cap_id) {
 		bcma_extpci_read_config(pc, dev, func, cap_ptr + 1, &cap_ptr,
 					sizeof(u8));
 		if (cap_ptr == 0x00)
 			return cap_ptr;
 		bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id,
 					sizeof(u8));
 	}

 	/* found the caller requested capability */
 	if ((buf != NULL) && (buflen != NULL)) {
 		u8 cap_data;

 		bufsize = *buflen;
 		if (!bufsize)
 			return cap_ptr;

 		*buflen = 0;

 		/* copy the cpability data excluding cap ID and next ptr */
 		cap_data = cap_ptr + 2;
 		if ((bufsize + cap_data)  > PCI_CONFIG_SPACE_SIZE)
 			bufsize = PCI_CONFIG_SPACE_SIZE - cap_data;
 		*buflen = bufsize;
 		while (bufsize--) {
 			bcma_extpci_read_config(pc, dev, func, cap_data, buf,
 						sizeof(u8));
 			cap_data++;
 			buf++;
 		}
 	}

 	return cap_ptr;
 }

 /* If the root port is capable of returning Config Request
  * Retry Status (CRS) Completion Status to software then
  * enable the feature.
  */
 static void __devinit bcma_core_pci_enable_crs(struct bcma_drv_pci *pc)
 {
 	struct bcma_bus *bus = pc->core->bus;
 	u8 cap_ptr, root_ctrl, root_cap, dev;
 	u16 val16;
 	int i;

 	cap_ptr = bcma_find_pci_capability(pc, 0, 0, PCI_CAP_ID_EXP, NULL,
 					   NULL);
 	root_cap = cap_ptr + PCI_EXP_RTCAP;
 	bcma_extpci_read_config(pc, 0, 0, root_cap, &val16, sizeof(u16));
 	if (val16 & BCMA_CORE_PCI_RC_CRS_VISIBILITY) {
 		/* Enable CRS software visibility */
 		root_ctrl = cap_ptr + PCI_EXP_RTCTL;
 		val16 = PCI_EXP_RTCTL_CRSSVE;
 		bcma_extpci_read_config(pc, 0, 0, root_ctrl, &val16,
 					sizeof(u16));

 		/* Initiate a configuration request to read the vendor id
 		 * field of the device function's config space header after
 		 * 100 ms wait time from the end of Reset. If the device is
 		 * not done with its internal initialization, it must at
 		 * least return a completion TLP, with a completion status
 		 * of "Configuration Request Retry Status (CRS)". The root
 		 * complex must complete the request to the host by returning
 		 * a read-data value of 0001h for the Vendor ID field and
 		 * all 1s for any additional bytes included in the request.
 		 * Poll using the config reads for max wait time of 1 sec or
 		 * until we receive the successful completion status. Repeat
 		 * the procedure for all the devices.
 		 */
 		for (dev = 1; dev < BCMA_PCI_SLOT_MAX; dev++) {
 			for (i = 0; i < 100000; i++) {
 				bcma_extpci_read_config(pc, dev, 0,
 							PCI_VENDOR_ID, &val16,
 							sizeof(val16));
 				if (val16 != 0x1)
 					break;
 				udelay(10);
 			}
 			if (val16 == 0x1)
 				bcma_err(bus, "PCI: Broken device in slot %d\n",
 					 dev);
 		}
 	}
 }

 void __devinit bcma_core_pci_hostmode_init(struct bcma_drv_pci *pc)
 {
 	struct bcma_bus *bus = pc->core->bus;
 	struct bcma_drv_pci_host *pc_host;
 	u32 tmp;
 	u32 pci_membase_1G;
 	unsigned long io_map_base;

 	bcma_info(bus, "PCIEcore in host mode found\n");

 	if (bus->sprom.boardflags_lo & BCMA_CORE_PCI_BFL_NOPCI) {
 		bcma_info(bus, "This PCIE core is disabled and not working\n");
 		return;
 	}

 	pc_host = kzalloc(sizeof(*pc_host), GFP_KERNEL);
 	if (!pc_host)  {
 		bcma_err(bus, "can not allocate memory");
 		return;
 	}

 	pc->host_controller = pc_host;
 	pc_host->pci_controller.io_resource = &pc_host->io_resource;
 	pc_host->pci_controller.mem_resource = &pc_host->mem_resource;
 	pc_host->pci_controller.pci_ops = &pc_host->pci_ops;
 	pc_host->pdev = pc;

 	pci_membase_1G = BCMA_SOC_PCI_DMA;
 	pc_host->host_cfg_addr = BCMA_SOC_PCI_CFG;

 	pc_host->pci_ops.read = bcma_core_pci_hostmode_read_config;
 	pc_host->pci_ops.write = bcma_core_pci_hostmode_write_config;

 	pc_host->mem_resource.name = "BCMA PCIcore external memory",
 	pc_host->mem_resource.start = BCMA_SOC_PCI_DMA;
 	pc_host->mem_resource.end = BCMA_SOC_PCI_DMA + BCMA_SOC_PCI_DMA_SZ - 1;
 	pc_host->mem_resource.flags = IORESOURCE_MEM | IORESOURCE_PCI_FIXED;

 	pc_host->io_resource.name = "BCMA PCIcore external I/O",
 	pc_host->io_resource.start = 0x100;
 	pc_host->io_resource.end = 0x7FF;
 	pc_host->io_resource.flags = IORESOURCE_IO | IORESOURCE_PCI_FIXED;

 	/* Reset RC */
 	usleep_range(3000, 5000);
 	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST_OE);
 	usleep_range(1000, 2000);
 	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST |
 			BCMA_CORE_PCI_CTL_RST_OE);

 	/* 64 MB I/O access window. On 4716, use
 	 * sbtopcie0 to access the device registers. We
 	 * can't use address match 2 (1 GB window) region
 	 * as mips can't generate 64-bit address on the
 	 * backplane.
 	 */
 	if (bus->chipinfo.id == BCMA_CHIP_ID_BCM4716 ||
 	    bus->chipinfo.id == BCMA_CHIP_ID_BCM4748) {
 		pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
 		pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
 					    BCMA_SOC_PCI_MEM_SZ - 1;
 		pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
 				BCMA_CORE_PCI_SBTOPCI_MEM | BCMA_SOC_PCI_MEM);
 	} else if (bus->chipinfo.id == BCMA_CHIP_ID_BCM4706) {
 		tmp = BCMA_CORE_PCI_SBTOPCI_MEM;
 		tmp |= BCMA_CORE_PCI_SBTOPCI_PREF;
 		tmp |= BCMA_CORE_PCI_SBTOPCI_BURST;
 		if (pc->core->core_unit == 0) {
 			pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
 			pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
 						    BCMA_SOC_PCI_MEM_SZ - 1;
 			pc_host->io_resource.start = 0x100;
 			pc_host->io_resource.end = 0x47F;
 			pci_membase_1G = BCMA_SOC_PCIE_DMA_H32;
 			pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
 					tmp | BCMA_SOC_PCI_MEM);
 		} else if (pc->core->core_unit == 1) {
 			pc_host->mem_resource.start = BCMA_SOC_PCI1_MEM;
 			pc_host->mem_resource.end = BCMA_SOC_PCI1_MEM +
 						    BCMA_SOC_PCI_MEM_SZ - 1;
 			pc_host->io_resource.start = 0x480;
 			pc_host->io_resource.end = 0x7FF;
 			pci_membase_1G = BCMA_SOC_PCIE1_DMA_H32;
 			pc_host->host_cfg_addr = BCMA_SOC_PCI1_CFG;
 			pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
 					tmp | BCMA_SOC_PCI1_MEM);
 		}
 	} else
 		pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
 				BCMA_CORE_PCI_SBTOPCI_IO);

 	/* 64 MB configuration access window */
 	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);

 	/* 1 GB memory access window */
 	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI2,
 			BCMA_CORE_PCI_SBTOPCI_MEM | pci_membase_1G);


 	/* As per PCI Express Base Spec 1.1 we need to wait for
 	 * at least 100 ms from the end of a reset (cold/warm/hot)
 	 * before issuing configuration requests to PCI Express
 	 * devices.
 	 */
 	msleep(100);

 	bcma_core_pci_enable_crs(pc);

 	/* Enable PCI bridge BAR0 memory & master access */
 	tmp = PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
 	bcma_extpci_write_config(pc, 0, 0, PCI_COMMAND, &tmp, sizeof(tmp));

 	/* Enable PCI interrupts */
 	pcicore_write32(pc, BCMA_CORE_PCI_IMASK, BCMA_CORE_PCI_IMASK_INTA);

 	/* Ok, ready to run, register it to the system.
 	 * The following needs change, if we want to port hostmode
 	 * to non-MIPS platform. */
 	io_map_base = (unsigned long)ioremap_nocache(pc_host->mem_resource.start,
 						     resource_size(&pc_host->mem_resource));
 	pc_host->pci_controller.io_map_base = io_map_base;
 	set_io_port_base(pc_host->pci_controller.io_map_base);
 	/* Give some time to the PCI controller to configure itself with the new
 	 * values. Not waiting at this point causes crashes of the machine. */
 	usleep_range(10000, 15000);
 	register_pci_controller(&pc_host->pci_controller);
 	return;
 }

 /* Early PCI fixup for a device on the PCI-core bridge. */
 static void bcma_core_pci_fixup_pcibridge(struct pci_dev *dev)
 {
 	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
 		/* This is not a device on the PCI-core bridge. */
 		return;
 	}
 	if (PCI_SLOT(dev->devfn) != 0)
 		return;

 	pr_info("PCI: Fixing up bridge %s\n", pci_name(dev));

 	/* Enable PCI bridge bus mastering and memory space */
 	pci_set_master(dev);
 	if (pcibios_enable_device(dev, ~0) < 0) {
 		pr_err("PCI: BCMA bridge enable failed\n");
 		return;
 	}

 	/* Enable PCI bridge BAR1 prefetch and burst */
 	pci_write_config_dword(dev, BCMA_PCI_BAR1_CONTROL, 3);
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_pcibridge);

 /* Early PCI fixup for all PCI-cores to set the correct memory address. */
 static void bcma_core_pci_fixup_addresses(struct pci_dev *dev)
 {
 	struct resource *res;
 	int pos, err;

 	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
 		/* This is not a device on the PCI-core bridge. */
 		return;
 	}
 	if (PCI_SLOT(dev->devfn) == 0)
 		return;

 	pr_info("PCI: Fixing up addresses %s\n", pci_name(dev));

 	for (pos = 0; pos < 6; pos++) {
 		res = &dev->resource[pos];
 		if (res->flags & (IORESOURCE_IO | IORESOURCE_MEM)) {
 			err = pci_assign_resource(dev, pos);
 			if (err)
 				pr_err("PCI: Problem fixing up the addresses on %s\n",
 				       pci_name(dev));
 		}
 	}
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_addresses);

 /* This function is called when doing a pci_enable_device().
  * We must first check if the device is a device on the PCI-core bridge. */
 int bcma_core_pci_plat_dev_init(struct pci_dev *dev)
 {
 	struct bcma_drv_pci_host *pc_host;

 	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
 		/* This is not a device on the PCI-core bridge. */
 		return -ENODEV;
 	}
 	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
 			       pci_ops);

 	pr_info("PCI: Fixing up device %s\n", pci_name(dev));

 	/* Fix up interrupt lines */
 	dev->irq = bcma_core_mips_irq(pc_host->pdev->core) + 2;
 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);

 	return 0;
 }
 EXPORT_SYMBOL(bcma_core_pci_plat_dev_init);

 /* PCI device IRQ mapping. */
 int bcma_core_pci_pcibios_map_irq(const struct pci_dev *dev)
 {
 	struct bcma_drv_pci_host *pc_host;

 	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
 		/* This is not a device on the PCI-core bridge. */
 		return -ENODEV;
 	}

 	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
 			       pci_ops);
 	return bcma_core_mips_irq(pc_host->pdev->core) + 2;
 }
 EXPORT_SYMBOL(bcma_core_pci_pcibios_map_irq);
	/*
	* Broadcom specific AMBA
	* PCI Core in hostmode
	*
	* Copyright 2005 - 2011, Broadcom Corporation
	* Copyright 2006, 2007, Michael Buesch <m@bues.ch>
	* Copyright 2011, 2012, Hauke Mehrtens <hauke@hauke-m.de>
	*
	* Licensed under the GNU/GPL. See COPYING for details.
	*/

	#include "bcma_private.h"
	#include <linux/pci.h>
	#include <linux/export.h>
	#include <linux/bcma/bcma.h>
	#include <asm/paccess.h>

	/* Probe a 32bit value on the bus and catch bus exceptions.
	* Returns nonzero on a bus exception.
	* This is MIPS specific */
	#define mips_busprobe32(val, addr) get_dbe((val), ((u32 *)(addr)))

	/* Assume one-hot slot wiring */
	#define BCMA_PCI_SLOT_MAX 16
	#define PCI_CONFIG_SPACE_SIZE 256

	bool __devinit bcma_core_pci_is_in_hostmode(struct bcma_drv_pci *pc)
	{
	struct bcma_bus *bus = pc->core->bus;
	u16 chipid_top;
	u32 tmp;

	chipid_top = (bus->chipinfo.id & 0xFF00);
	if (chipid_top != 0x4700 &&
	chipid_top != 0x5300)
	return false;

	bcma_core_enable(pc->core, 0);

	return !mips_busprobe32(tmp, pc->core->io_addr);
	}

	static u32 bcma_pcie_read_config(struct bcma_drv_pci *pc, u32 address)
	{
	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
	return pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_DATA);
	}

	static void bcma_pcie_write_config(struct bcma_drv_pci *pc, u32 address,
	u32 data)
	{
	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_ADDR, address);
	pcicore_read32(pc, BCMA_CORE_PCI_CONFIG_ADDR);
	pcicore_write32(pc, BCMA_CORE_PCI_CONFIG_DATA, data);
	}

	static u32 bcma_get_cfgspace_addr(struct bcma_drv_pci *pc, unsigned int dev,
	unsigned int func, unsigned int off)
	{
	u32 addr = 0;

	/* Issue config commands only when the data link is up (atleast
	* one external pcie device is present).
	*/
	if (dev >= 2 \|\| !(bcma_pcie_read(pc, BCMA_CORE_PCI_DLLP_LSREG)
	& BCMA_CORE_PCI_DLLP_LSREG_LINKUP))
	goto out;

	/* Type 0 transaction */
	/* Slide the PCI window to the appropriate slot */
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);
	/* Calculate the address */
	addr = pc->host_controller->host_cfg_addr;
	addr \|= (dev << BCMA_CORE_PCI_CFG_SLOT_SHIFT);
	addr \|= (func << BCMA_CORE_PCI_CFG_FUN_SHIFT);
	addr \|= (off & ~3);

	out:
	return addr;
	}

	static int bcma_extpci_read_config(struct bcma_drv_pci *pc, unsigned int dev,
	unsigned int func, unsigned int off,
	void *buf, int len)
	{
	int err = -EINVAL;
	u32 addr, val;
	void __iomem *mmio = 0;

	WARN_ON(!pc->hostmode);
	if (unlikely(len != 1 && len != 2 && len != 4))
	goto out;
	if (dev == 0) {
	/* we support only two functions on device 0 */
	if (func > 1)
	return -EINVAL;

	/* accesses to config registers with offsets >= 256
	* requires indirect access.
	*/
	if (off >= PCI_CONFIG_SPACE_SIZE) {
	addr = (func << 12);
	addr \|= (off & 0x0FFF);
	val = bcma_pcie_read_config(pc, addr);
	} else {
	addr = BCMA_CORE_PCI_PCICFG0;
	addr \|= (func << 8);
	addr \|= (off & 0xfc);
	val = pcicore_read32(pc, addr);
	}
	} else {
	addr = bcma_get_cfgspace_addr(pc, dev, func, off);
	if (unlikely(!addr))
	goto out;
	err = -ENOMEM;
	mmio = ioremap_nocache(addr, sizeof(val));
	if (!mmio)
	goto out;

	if (mips_busprobe32(val, mmio)) {
	val = 0xffffffff;
	goto unmap;
	}

	val = readl(mmio);
	}
	val >>= (8 * (off & 3));

	switch (len) {
	case 1:
	((u8 )buf) = (u8)val;
	break;
	case 2:
	((u16 )buf) = (u16)val;
	break;
	case 4:
	((u32 )buf) = (u32)val;
	break;
	}
	err = 0;
	unmap:
	if (mmio)
	iounmap(mmio);
	out:
	return err;
	}

	static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
	unsigned int func, unsigned int off,
	const void *buf, int len)
	{
	int err = -EINVAL;
	u32 addr = 0, val = 0;
	void __iomem *mmio = 0;
	u16 chipid = pc->core->bus->chipinfo.id;

	WARN_ON(!pc->hostmode);
	if (unlikely(len != 1 && len != 2 && len != 4))
	goto out;
	if (dev == 0) {
	/* accesses to config registers with offsets >= 256
	* requires indirect access.
	*/
	if (off < PCI_CONFIG_SPACE_SIZE) {
	addr = pc->core->addr + BCMA_CORE_PCI_PCICFG0;
	addr \|= (func << 8);
	addr \|= (off & 0xfc);
	mmio = ioremap_nocache(addr, sizeof(val));
	if (!mmio)
	goto out;
	}
	} else {
	addr = bcma_get_cfgspace_addr(pc, dev, func, off);
	if (unlikely(!addr))
	goto out;
	err = -ENOMEM;
	mmio = ioremap_nocache(addr, sizeof(val));
	if (!mmio)
	goto out;

	if (mips_busprobe32(val, mmio)) {
	val = 0xffffffff;
	goto unmap;
	}
	}

	switch (len) {
	case 1:
	val = readl(mmio);
	val &= ~(0xFF << (8 * (off & 3)));
	val \|= ((const u8 )buf) << (8 * (off & 3));
	break;
	case 2:
	val = readl(mmio);
	val &= ~(0xFFFF << (8 * (off & 3)));
	val \|= ((const u16 )buf) << (8 * (off & 3));
	break;
	case 4:
	val = ((const u32 )buf);
	break;
	}
	if (dev == 0 && !addr) {
	/* accesses to config registers with offsets >= 256
	* requires indirect access.
	*/
	addr = (func << 12);
	addr \|= (off & 0x0FFF);
	bcma_pcie_write_config(pc, addr, val);
	} else {
	writel(val, mmio);

	if (chipid == BCMA_CHIP_ID_BCM4716 \|\|
	chipid == BCMA_CHIP_ID_BCM4748)
	readl(mmio);
	}

	err = 0;
	unmap:
	if (mmio)
	iounmap(mmio);
	out:
	return err;
	}

	static int bcma_core_pci_hostmode_read_config(struct pci_bus *bus,
	unsigned int devfn,
	int reg, int size, u32 *val)
	{
	unsigned long flags;
	int err;
	struct bcma_drv_pci *pc;
	struct bcma_drv_pci_host *pc_host;

	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
	pc = pc_host->pdev;

	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
	err = bcma_extpci_read_config(pc, PCI_SLOT(devfn),
	PCI_FUNC(devfn), reg, val, size);
	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);

	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
	}

	static int bcma_core_pci_hostmode_write_config(struct pci_bus *bus,
	unsigned int devfn,
	int reg, int size, u32 val)
	{
	unsigned long flags;
	int err;
	struct bcma_drv_pci *pc;
	struct bcma_drv_pci_host *pc_host;

	pc_host = container_of(bus->ops, struct bcma_drv_pci_host, pci_ops);
	pc = pc_host->pdev;

	spin_lock_irqsave(&pc_host->cfgspace_lock, flags);
	err = bcma_extpci_write_config(pc, PCI_SLOT(devfn),
	PCI_FUNC(devfn), reg, &val, size);
	spin_unlock_irqrestore(&pc_host->cfgspace_lock, flags);

	return err ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
	}

	/* return cap_offset if requested capability exists in the PCI config space */
	static u8 __devinit bcma_find_pci_capability(struct bcma_drv_pci *pc,
	unsigned int dev,
	unsigned int func, u8 req_cap_id,
	unsigned char buf, u32 buflen)
	{
	u8 cap_id;
	u8 cap_ptr = 0;
	u32 bufsize;
	u8 byte_val;

	/* check for Header type 0 */
	bcma_extpci_read_config(pc, dev, func, PCI_HEADER_TYPE, &byte_val,
	sizeof(u8));
	if ((byte_val & 0x7f) != PCI_HEADER_TYPE_NORMAL)
	return cap_ptr;

	/* check if the capability pointer field exists */
	bcma_extpci_read_config(pc, dev, func, PCI_STATUS, &byte_val,
	sizeof(u8));
	if (!(byte_val & PCI_STATUS_CAP_LIST))
	return cap_ptr;

	/* check if the capability pointer is 0x00 */
	bcma_extpci_read_config(pc, dev, func, PCI_CAPABILITY_LIST, &cap_ptr,
	sizeof(u8));
	if (cap_ptr == 0x00)
	return cap_ptr;

	/* loop thr'u the capability list and see if the requested capabilty
	* exists */
	bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id, sizeof(u8));
	while (cap_id != req_cap_id) {
	bcma_extpci_read_config(pc, dev, func, cap_ptr + 1, &cap_ptr,
	sizeof(u8));
	if (cap_ptr == 0x00)
	return cap_ptr;
	bcma_extpci_read_config(pc, dev, func, cap_ptr, &cap_id,
	sizeof(u8));
	}

	/* found the caller requested capability */
	if ((buf != NULL) && (buflen != NULL)) {
	u8 cap_data;

	bufsize = *buflen;
	if (!bufsize)
	return cap_ptr;

	*buflen = 0;

	/* copy the cpability data excluding cap ID and next ptr */
	cap_data = cap_ptr + 2;
	if ((bufsize + cap_data) > PCI_CONFIG_SPACE_SIZE)
	bufsize = PCI_CONFIG_SPACE_SIZE - cap_data;
	*buflen = bufsize;
	while (bufsize--) {
	bcma_extpci_read_config(pc, dev, func, cap_data, buf,
	sizeof(u8));
	cap_data++;
	buf++;
	}
	}

	return cap_ptr;
	}

	/* If the root port is capable of returning Config Request
	* Retry Status (CRS) Completion Status to software then
	* enable the feature.
	*/
	static void __devinit bcma_core_pci_enable_crs(struct bcma_drv_pci *pc)
	{
	struct bcma_bus *bus = pc->core->bus;
	u8 cap_ptr, root_ctrl, root_cap, dev;
	u16 val16;
	int i;

	cap_ptr = bcma_find_pci_capability(pc, 0, 0, PCI_CAP_ID_EXP, NULL,
	NULL);
	root_cap = cap_ptr + PCI_EXP_RTCAP;
	bcma_extpci_read_config(pc, 0, 0, root_cap, &val16, sizeof(u16));
	if (val16 & BCMA_CORE_PCI_RC_CRS_VISIBILITY) {
	/* Enable CRS software visibility */
	root_ctrl = cap_ptr + PCI_EXP_RTCTL;
	val16 = PCI_EXP_RTCTL_CRSSVE;
	bcma_extpci_read_config(pc, 0, 0, root_ctrl, &val16,
	sizeof(u16));

	/* Initiate a configuration request to read the vendor id
	* field of the device function's config space header after
	* 100 ms wait time from the end of Reset. If the device is
	* not done with its internal initialization, it must at
	* least return a completion TLP, with a completion status
	* of "Configuration Request Retry Status (CRS)". The root
	* complex must complete the request to the host by returning
	* a read-data value of 0001h for the Vendor ID field and
	* all 1s for any additional bytes included in the request.
	* Poll using the config reads for max wait time of 1 sec or
	* until we receive the successful completion status. Repeat
	* the procedure for all the devices.
	*/
	for (dev = 1; dev < BCMA_PCI_SLOT_MAX; dev++) {
	for (i = 0; i < 100000; i++) {
	bcma_extpci_read_config(pc, dev, 0,
	PCI_VENDOR_ID, &val16,
	sizeof(val16));
	if (val16 != 0x1)
	break;
	udelay(10);
	}
	if (val16 == 0x1)
	bcma_err(bus, "PCI: Broken device in slot %d\n",
	dev);
	}
	}
	}

	void __devinit bcma_core_pci_hostmode_init(struct bcma_drv_pci *pc)
	{
	struct bcma_bus *bus = pc->core->bus;
	struct bcma_drv_pci_host *pc_host;
	u32 tmp;
	u32 pci_membase_1G;
	unsigned long io_map_base;

	bcma_info(bus, "PCIEcore in host mode found\n");

	if (bus->sprom.boardflags_lo & BCMA_CORE_PCI_BFL_NOPCI) {
	bcma_info(bus, "This PCIE core is disabled and not working\n");
	return;
	}

	pc_host = kzalloc(sizeof(*pc_host), GFP_KERNEL);
	if (!pc_host) {
	bcma_err(bus, "can not allocate memory");
	return;
	}

	pc->host_controller = pc_host;
	pc_host->pci_controller.io_resource = &pc_host->io_resource;
	pc_host->pci_controller.mem_resource = &pc_host->mem_resource;
	pc_host->pci_controller.pci_ops = &pc_host->pci_ops;
	pc_host->pdev = pc;

	pci_membase_1G = BCMA_SOC_PCI_DMA;
	pc_host->host_cfg_addr = BCMA_SOC_PCI_CFG;

	pc_host->pci_ops.read = bcma_core_pci_hostmode_read_config;
	pc_host->pci_ops.write = bcma_core_pci_hostmode_write_config;

	pc_host->mem_resource.name = "BCMA PCIcore external memory",
	pc_host->mem_resource.start = BCMA_SOC_PCI_DMA;
	pc_host->mem_resource.end = BCMA_SOC_PCI_DMA + BCMA_SOC_PCI_DMA_SZ - 1;
	pc_host->mem_resource.flags = IORESOURCE_MEM \| IORESOURCE_PCI_FIXED;

	pc_host->io_resource.name = "BCMA PCIcore external I/O",
	pc_host->io_resource.start = 0x100;
	pc_host->io_resource.end = 0x7FF;
	pc_host->io_resource.flags = IORESOURCE_IO \| IORESOURCE_PCI_FIXED;

	/* Reset RC */
	usleep_range(3000, 5000);
	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST_OE);
	usleep_range(1000, 2000);
	pcicore_write32(pc, BCMA_CORE_PCI_CTL, BCMA_CORE_PCI_CTL_RST \|
	BCMA_CORE_PCI_CTL_RST_OE);

	/* 64 MB I/O access window. On 4716, use
	* sbtopcie0 to access the device registers. We
	* can't use address match 2 (1 GB window) region
	* as mips can't generate 64-bit address on the
	* backplane.
	*/
	if (bus->chipinfo.id == BCMA_CHIP_ID_BCM4716 \|\|
	bus->chipinfo.id == BCMA_CHIP_ID_BCM4748) {
	pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
	pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
	BCMA_SOC_PCI_MEM_SZ - 1;
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
	BCMA_CORE_PCI_SBTOPCI_MEM \| BCMA_SOC_PCI_MEM);
	} else if (bus->chipinfo.id == BCMA_CHIP_ID_BCM4706) {
	tmp = BCMA_CORE_PCI_SBTOPCI_MEM;
	tmp \|= BCMA_CORE_PCI_SBTOPCI_PREF;
	tmp \|= BCMA_CORE_PCI_SBTOPCI_BURST;
	if (pc->core->core_unit == 0) {
	pc_host->mem_resource.start = BCMA_SOC_PCI_MEM;
	pc_host->mem_resource.end = BCMA_SOC_PCI_MEM +
	BCMA_SOC_PCI_MEM_SZ - 1;
	pc_host->io_resource.start = 0x100;
	pc_host->io_resource.end = 0x47F;
	pci_membase_1G = BCMA_SOC_PCIE_DMA_H32;
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
	tmp \| BCMA_SOC_PCI_MEM);
	} else if (pc->core->core_unit == 1) {
	pc_host->mem_resource.start = BCMA_SOC_PCI1_MEM;
	pc_host->mem_resource.end = BCMA_SOC_PCI1_MEM +
	BCMA_SOC_PCI_MEM_SZ - 1;
	pc_host->io_resource.start = 0x480;
	pc_host->io_resource.end = 0x7FF;
	pci_membase_1G = BCMA_SOC_PCIE1_DMA_H32;
	pc_host->host_cfg_addr = BCMA_SOC_PCI1_CFG;
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
	tmp \| BCMA_SOC_PCI1_MEM);
	}
	} else
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI0,
	BCMA_CORE_PCI_SBTOPCI_IO);

	/* 64 MB configuration access window */
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI1, BCMA_CORE_PCI_SBTOPCI_CFG0);

	/* 1 GB memory access window */
	pcicore_write32(pc, BCMA_CORE_PCI_SBTOPCI2,
	BCMA_CORE_PCI_SBTOPCI_MEM \| pci_membase_1G);


	/* As per PCI Express Base Spec 1.1 we need to wait for
	* at least 100 ms from the end of a reset (cold/warm/hot)
	* before issuing configuration requests to PCI Express
	* devices.
	*/
	msleep(100);

	bcma_core_pci_enable_crs(pc);

	/* Enable PCI bridge BAR0 memory & master access */
	tmp = PCI_COMMAND_MASTER \| PCI_COMMAND_MEMORY;
	bcma_extpci_write_config(pc, 0, 0, PCI_COMMAND, &tmp, sizeof(tmp));

	/* Enable PCI interrupts */
	pcicore_write32(pc, BCMA_CORE_PCI_IMASK, BCMA_CORE_PCI_IMASK_INTA);

	/* Ok, ready to run, register it to the system.
	* The following needs change, if we want to port hostmode
	* to non-MIPS platform. */
	io_map_base = (unsigned long)ioremap_nocache(pc_host->mem_resource.start,
	resource_size(&pc_host->mem_resource));
	pc_host->pci_controller.io_map_base = io_map_base;
	set_io_port_base(pc_host->pci_controller.io_map_base);
	/* Give some time to the PCI controller to configure itself with the new
	* values. Not waiting at this point causes crashes of the machine. */
	usleep_range(10000, 15000);
	register_pci_controller(&pc_host->pci_controller);
	return;
	}

	/* Early PCI fixup for a device on the PCI-core bridge. */
	static void bcma_core_pci_fixup_pcibridge(struct pci_dev *dev)
	{
	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
	/* This is not a device on the PCI-core bridge. */
	return;
	}
	if (PCI_SLOT(dev->devfn) != 0)
	return;

	pr_info("PCI: Fixing up bridge %s\n", pci_name(dev));

	/* Enable PCI bridge bus mastering and memory space */
	pci_set_master(dev);
	if (pcibios_enable_device(dev, ~0) < 0) {
	pr_err("PCI: BCMA bridge enable failed\n");
	return;
	}

	/* Enable PCI bridge BAR1 prefetch and burst */
	pci_write_config_dword(dev, BCMA_PCI_BAR1_CONTROL, 3);
	}
	DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_pcibridge);

	/* Early PCI fixup for all PCI-cores to set the correct memory address. */
	static void bcma_core_pci_fixup_addresses(struct pci_dev *dev)
	{
	struct resource *res;
	int pos, err;

	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
	/* This is not a device on the PCI-core bridge. */
	return;
	}
	if (PCI_SLOT(dev->devfn) == 0)
	return;

	pr_info("PCI: Fixing up addresses %s\n", pci_name(dev));

	for (pos = 0; pos < 6; pos++) {
	res = &dev->resource[pos];
	if (res->flags & (IORESOURCE_IO \| IORESOURCE_MEM)) {
	err = pci_assign_resource(dev, pos);
	if (err)
	pr_err("PCI: Problem fixing up the addresses on %s\n",
	pci_name(dev));
	}
	}
	}
	DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, bcma_core_pci_fixup_addresses);

	/* This function is called when doing a pci_enable_device().
	* We must first check if the device is a device on the PCI-core bridge. */
	int bcma_core_pci_plat_dev_init(struct pci_dev *dev)
	{
	struct bcma_drv_pci_host *pc_host;

	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
	/* This is not a device on the PCI-core bridge. */
	return -ENODEV;
	}
	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
	pci_ops);

	pr_info("PCI: Fixing up device %s\n", pci_name(dev));

	/* Fix up interrupt lines */
	dev->irq = bcma_core_mips_irq(pc_host->pdev->core) + 2;
	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);

	return 0;
	}
	EXPORT_SYMBOL(bcma_core_pci_plat_dev_init);

	/* PCI device IRQ mapping. */
	int bcma_core_pci_pcibios_map_irq(const struct pci_dev *dev)
	{
	struct bcma_drv_pci_host *pc_host;

	if (dev->bus->ops->read != bcma_core_pci_hostmode_read_config) {
	/* This is not a device on the PCI-core bridge. */
	return -ENODEV;
	}

	pc_host = container_of(dev->bus->ops, struct bcma_drv_pci_host,
	pci_ops);
	return bcma_core_mips_irq(pc_host->pdev->core) + 2;
	}
	EXPORT_SYMBOL(bcma_core_pci_pcibios_map_irq);