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Release 4.14 arch/sh/drivers/pci/ops-sh7786.c

/*
 * Generic SH7786 PCI-Express operations.
 *
 *  Copyright (C) 2009 - 2010  Paul Mundt
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License v2. See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include "pcie-sh7786.h"

enum {
	
PCI_ACCESS_READ,
	
PCI_ACCESS_WRITE,
};


static int sh7786_pcie_config_access(unsigned char access_type, struct pci_bus *bus, unsigned int devfn, int where, u32 *data) { struct pci_channel *chan = bus->sysdata; int dev, func, type, reg; dev = PCI_SLOT(devfn); func = PCI_FUNC(devfn); type = !!bus->parent; reg = where & ~3; if (bus->number > 255 || dev > 31 || func > 7) return PCIBIOS_FUNC_NOT_SUPPORTED; /* * While each channel has its own memory-mapped extended config * space, it's generally only accessible when in endpoint mode. * When in root complex mode, the controller is unable to target * itself with either type 0 or type 1 accesses, and indeed, any * controller initiated target transfer to its own config space * result in a completer abort. * * Each channel effectively only supports a single device, but as * the same channel <-> device access works for any PCI_SLOT() * value, we cheat a bit here and bind the controller's config * space to devfn 0 in order to enable self-enumeration. In this * case the regular PAR/PDR path is sidelined and the mangled * config access itself is initiated as a SuperHyway transaction. */ if (pci_is_root_bus(bus)) { if (dev == 0) { if (access_type == PCI_ACCESS_READ) *data = pci_read_reg(chan, PCI_REG(reg)); else pci_write_reg(chan, *data, PCI_REG(reg)); return PCIBIOS_SUCCESSFUL; } else if (dev > 1) return PCIBIOS_DEVICE_NOT_FOUND; } /* Clear errors */ pci_write_reg(chan, pci_read_reg(chan, SH4A_PCIEERRFR), SH4A_PCIEERRFR); /* Set the PIO address */ pci_write_reg(chan, (bus->number << 24) | (dev << 19) | (func << 16) | reg, SH4A_PCIEPAR); /* Enable the configuration access */ pci_write_reg(chan, (1 << 31) | (type << 8), SH4A_PCIEPCTLR); /* Check for errors */ if (pci_read_reg(chan, SH4A_PCIEERRFR) & 0x10) return PCIBIOS_DEVICE_NOT_FOUND; /* Check for master and target aborts */ if (pci_read_reg(chan, SH4A_PCIEPCICONF1) & ((1 << 29) | (1 << 28))) return PCIBIOS_DEVICE_NOT_FOUND; if (access_type == PCI_ACCESS_READ) *data = pci_read_reg(chan, SH4A_PCIEPDR); else pci_write_reg(chan, *data, SH4A_PCIEPDR); /* Disable the configuration access */ pci_write_reg(chan, 0, SH4A_PCIEPCTLR); return PCIBIOS_SUCCESSFUL; }

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Paul Mundt303100.00%5100.00%
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static int sh7786_pcie_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { unsigned long flags; int ret; u32 data; if ((size == 2) && (where & 1)) return PCIBIOS_BAD_REGISTER_NUMBER; else if ((size == 4) && (where & 3)) return PCIBIOS_BAD_REGISTER_NUMBER; raw_spin_lock_irqsave(&pci_config_lock, flags); ret = sh7786_pcie_config_access(PCI_ACCESS_READ, bus, devfn, where, &data); if (ret != PCIBIOS_SUCCESSFUL) { *val = 0xffffffff; goto out; } if (size == 1) *val = (data >> ((where & 3) << 3)) & 0xff; else if (size == 2) *val = (data >> ((where & 2) << 3)) & 0xffff; else *val = data; dev_dbg(&bus->dev, "pcie-config-read: bus=%3d devfn=0x%04x " "where=0x%04x size=%d val=0x%08lx\n", bus->number, devfn, where, size, (unsigned long)*val); out: raw_spin_unlock_irqrestore(&pci_config_lock, flags); return ret; }

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Paul Mundt208100.00%3100.00%
Total208100.00%3100.00%


static int sh7786_pcie_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) { unsigned long flags; int shift, ret; u32 data; if ((size == 2) && (where & 1)) return PCIBIOS_BAD_REGISTER_NUMBER; else if ((size == 4) && (where & 3)) return PCIBIOS_BAD_REGISTER_NUMBER; raw_spin_lock_irqsave(&pci_config_lock, flags); ret = sh7786_pcie_config_access(PCI_ACCESS_READ, bus, devfn, where, &data); if (ret != PCIBIOS_SUCCESSFUL) goto out; dev_dbg(&bus->dev, "pcie-config-write: bus=%3d devfn=0x%04x " "where=0x%04x size=%d val=%08lx\n", bus->number, devfn, where, size, (unsigned long)val); if (size == 1) { shift = (where & 3) << 3; data &= ~(0xff << shift); data |= ((val & 0xff) << shift); } else if (size == 2) { shift = (where & 2) << 3; data &= ~(0xffff << shift); data |= ((val & 0xffff) << shift); } else data = val; ret = sh7786_pcie_config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data); out: raw_spin_unlock_irqrestore(&pci_config_lock, flags); return ret; }

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Paul Mundt244100.00%2100.00%
Total244100.00%2100.00%

struct pci_ops sh7786_pci_ops = { .read = sh7786_pcie_read, .write = sh7786_pcie_write, };

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Paul Mundt797100.00%6100.00%
Total797100.00%6100.00%
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