1 files changed, 53 insertions, 16 deletions

diff --git a/arch/sh/drivers/pci/ops-sh7786.c b/arch/sh/drivers/pci/ops-sh7786.c
index 48f594b9582b..128421009e3f 100644
--- a/arch/sh/drivers/pci/ops-sh7786.c
+++ b/arch/sh/drivers/pci/ops-sh7786.c
@@ -1,7 +1,7 @@
 /*
  * Generic SH7786 PCI-Express operations.
  *
- *  Copyright (C) 2009  Paul Mundt
+ *  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
@@ -19,37 +19,72 @@ enum {
 	PCI_ACCESS_WRITE,
 };
 
-static DEFINE_SPINLOCK(sh7786_pcie_lock);
-
 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;
+	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;
-	if (devfn)
-		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	/*
+	 * 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) | (where & ~3), SH4A_PCIEPAR);
+				(func << 16) | reg, SH4A_PCIEPAR);
 
 	/* Enable the configuration access */
-	pci_write_reg(chan, (1 << 31), SH4A_PCIEPCTLR);
+	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);
 
-	/* Check for master and target aborts */
-	if (pci_read_reg(chan, SH4A_PCIEPCICONF1) & ((1 << 29) | (1 << 28)))
-		return PCIBIOS_DEVICE_NOT_FOUND;
+	/* Disable the configuration access */
+	pci_write_reg(chan, 0, SH4A_PCIEPCTLR);
 
 	return PCIBIOS_SUCCESSFUL;
 }
@@ -66,11 +101,13 @@ static int sh7786_pcie_read(struct pci_bus *bus, unsigned int devfn,
 	else if ((size == 4) && (where & 3))
 		return PCIBIOS_BAD_REGISTER_NUMBER;
 
-	spin_lock_irqsave(&sh7786_pcie_lock, flags);
+	raw_spin_lock_irqsave(&pci_config_lock, flags);
 	ret = sh7786_pcie_config_access(PCI_ACCESS_READ, bus,
 					devfn, where, &data);
-	if (ret != PCIBIOS_SUCCESSFUL)
+	if (ret != PCIBIOS_SUCCESSFUL) {
+		*val = 0xffffffff;
 		goto out;
+	}
 
 	if (size == 1)
 		*val = (data >> ((where & 3) << 3)) & 0xff;
@@ -84,7 +121,7 @@ static int sh7786_pcie_read(struct pci_bus *bus, unsigned int devfn,
 		devfn, where, size, (unsigned long)*val);
 
 out:
-	spin_unlock_irqrestore(&sh7786_pcie_lock, flags);
+	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
 	return ret;
 }
 
@@ -100,7 +137,7 @@ static int sh7786_pcie_write(struct pci_bus *bus, unsigned int devfn,
 	else if ((size == 4) && (where & 3))
 		return PCIBIOS_BAD_REGISTER_NUMBER;
 
-	spin_lock_irqsave(&sh7786_pcie_lock, flags);
+	raw_spin_lock_irqsave(&pci_config_lock, flags);
 	ret = sh7786_pcie_config_access(PCI_ACCESS_READ, bus,
 					devfn, where, &data);
 	if (ret != PCIBIOS_SUCCESSFUL)
@@ -124,7 +161,7 @@ static int sh7786_pcie_write(struct pci_bus *bus, unsigned int devfn,
 	ret = sh7786_pcie_config_access(PCI_ACCESS_WRITE, bus,
 					devfn, where, &data);
 out:
-	spin_unlock_irqrestore(&sh7786_pcie_lock, flags);
+	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
 	return ret;
 }