1 files changed, 262 insertions, 0 deletions
diff --git a/arch/x86/pci/mrst.c b/arch/x86/pci/mrst.c
new file mode 100644
index 00000000000..8bf2fcb88d0
--- /dev/null
+++ b/arch/x86/pci/mrst.c
@@ -0,0 +1,262 @@
+/*
+ * Moorestown PCI support
+ *   Copyright (c) 2008 Intel Corporation
+ *     Jesse Barnes <jesse.barnes@intel.com>
+ *
+ * Moorestown has an interesting PCI implementation:
+ *   - configuration space is memory mapped (as defined by MCFG)
+ *   - Lincroft devices also have a real, type 1 configuration space
+ *   - Early Lincroft silicon has a type 1 access bug that will cause
+ *     a hang if non-existent devices are accessed
+ *   - some devices have the "fixed BAR" capability, which means
+ *     they can't be relocated or modified; check for that during
+ *     BAR sizing
+ *
+ * So, we use the MCFG space for all reads and writes, but also send
+ * Lincroft writes to type 1 space.  But only read/write if the device
+ * actually exists, otherwise return all 1s for reads and bit bucket
+ * the writes.
+ */
+
+#include <linux/sched.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/dmi.h>
+
+#include <asm/acpi.h>
+#include <asm/segment.h>
+#include <asm/io.h>
+#include <asm/smp.h>
+#include <asm/pci_x86.h>
+#include <asm/hw_irq.h>
+#include <asm/io_apic.h>
+
+#define PCIE_CAP_OFFSET	0x100
+
+/* Fixed BAR fields */
+#define PCIE_VNDR_CAP_ID_FIXED_BAR 0x00	/* Fixed BAR (TBD) */
+#define PCI_FIXED_BAR_0_SIZE	0x04
+#define PCI_FIXED_BAR_1_SIZE	0x08
+#define PCI_FIXED_BAR_2_SIZE	0x0c
+#define PCI_FIXED_BAR_3_SIZE	0x10
+#define PCI_FIXED_BAR_4_SIZE	0x14
+#define PCI_FIXED_BAR_5_SIZE	0x1c
+
+/**
+ * fixed_bar_cap - return the offset of the fixed BAR cap if found
+ * @bus: PCI bus
+ * @devfn: device in question
+ *
+ * Look for the fixed BAR cap on @bus and @devfn, returning its offset
+ * if found or 0 otherwise.
+ */
+static int fixed_bar_cap(struct pci_bus *bus, unsigned int devfn)
+{
+	int pos;
+	u32 pcie_cap = 0, cap_data;
+
+	pos = PCIE_CAP_OFFSET;
+
+	if (!raw_pci_ext_ops)
+		return 0;
+
+	while (pos) {
+		if (raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
+					  devfn, pos, 4, &pcie_cap))
+			return 0;
+
+		if (pcie_cap == 0xffffffff)
+			return 0;
+
+		if (PCI_EXT_CAP_ID(pcie_cap) == PCI_EXT_CAP_ID_VNDR) {
+			raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
+					      devfn, pos + 4, 4, &cap_data);
+			if ((cap_data & 0xffff) == PCIE_VNDR_CAP_ID_FIXED_BAR)
+				return pos;
+		}
+
+		pos = pcie_cap >> 20;
+	}
+
+	return 0;
+}
+
+static int pci_device_update_fixed(struct pci_bus *bus, unsigned int devfn,
+				   int reg, int len, u32 val, int offset)
+{
+	u32 size;
+	unsigned int domain, busnum;
+	int bar = (reg - PCI_BASE_ADDRESS_0) >> 2;
+
+	domain = pci_domain_nr(bus);
+	busnum = bus->number;
+
+	if (val == ~0 && len == 4) {
+		unsigned long decode;
+
+		raw_pci_ext_ops->read(domain, busnum, devfn,
+			       offset + 8 + (bar * 4), 4, &size);
+
+		/* Turn the size into a decode pattern for the sizing code */
+		if (size) {
+			decode = size - 1;
+			decode |= decode >> 1;
+			decode |= decode >> 2;
+			decode |= decode >> 4;
+			decode |= decode >> 8;
+			decode |= decode >> 16;
+			decode++;
+			decode = ~(decode - 1);
+		} else {
+			decode = ~0;
+		}
+
+		/*
+		 * If val is all ones, the core code is trying to size the reg,
+		 * so update the mmconfig space with the real size.
+		 *
+		 * Note: this assumes the fixed size we got is a power of two.
+		 */
+		return raw_pci_ext_ops->write(domain, busnum, devfn, reg, 4,
+				       decode);
+	}
+
+	/* This is some other kind of BAR write, so just do it. */
+	return raw_pci_ext_ops->write(domain, busnum, devfn, reg, len, val);
+}
+
+/**
+ * type1_access_ok - check whether to use type 1
+ * @bus: bus number
+ * @devfn: device & function in question
+ *
+ * If the bus is on a Lincroft chip and it exists, or is not on a Lincroft at
+ * all, the we can go ahead with any reads & writes.  If it's on a Lincroft,
+ * but doesn't exist, avoid the access altogether to keep the chip from
+ * hanging.
+ */
+static bool type1_access_ok(unsigned int bus, unsigned int devfn, int reg)
+{
+	/* This is a workaround for A0 LNC bug where PCI status register does
+	 * not have new CAP bit set. can not be written by SW either.
+	 *
+	 * PCI header type in real LNC indicates a single function device, this
+	 * will prevent probing other devices under the same function in PCI
+	 * shim. Therefore, use the header type in shim instead.
+	 */
+	if (reg >= 0x100 || reg == PCI_STATUS || reg == PCI_HEADER_TYPE)
+		return 0;
+	if (bus == 0 && (devfn == PCI_DEVFN(2, 0) || devfn == PCI_DEVFN(0, 0)))
+		return 1;
+	return 0; /* langwell on others */
+}
+
+static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
+		    int size, u32 *value)
+{
+	if (type1_access_ok(bus->number, devfn, where))
+		return pci_direct_conf1.read(pci_domain_nr(bus), bus->number,
+					devfn, where, size, value);
+	return raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
+			      devfn, where, size, value);
+}
+
+static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
+		     int size, u32 value)
+{
+	int offset;
+
+	/* On MRST, there is no PCI ROM BAR, this will cause a subsequent read
+	 * to ROM BAR return 0 then being ignored.
+	 */
+	if (where == PCI_ROM_ADDRESS)
+		return 0;
+
+	/*
+	 * Devices with fixed BARs need special handling:
+	 *   - BAR sizing code will save, write ~0, read size, restore
+	 *   - so writes to fixed BARs need special handling
+	 *   - other writes to fixed BAR devices should go through mmconfig
+	 */
+	offset = fixed_bar_cap(bus, devfn);
+	if (offset &&
+	    (where >= PCI_BASE_ADDRESS_0 && where <= PCI_BASE_ADDRESS_5)) {
+		return pci_device_update_fixed(bus, devfn, where, size, value,
+					       offset);
+	}
+
+	/*
+	 * On Moorestown update both real & mmconfig space
+	 * Note: early Lincroft silicon can't handle type 1 accesses to
+	 *       non-existent devices, so just eat the write in that case.
+	 */
+	if (type1_access_ok(bus->number, devfn, where))
+		return pci_direct_conf1.write(pci_domain_nr(bus), bus->number,
+					      devfn, where, size, value);
+	return raw_pci_ext_ops->write(pci_domain_nr(bus), bus->number, devfn,
+			       where, size, value);
+}
+
+static int mrst_pci_irq_enable(struct pci_dev *dev)
+{
+	u8 pin;
+	struct io_apic_irq_attr irq_attr;
+
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+
+	/* MRST only have IOAPIC, the PCI irq lines are 1:1 mapped to
+	 * IOAPIC RTE entries, so we just enable RTE for the device.
+	 */
+	irq_attr.ioapic = mp_find_ioapic(dev->irq);
+	irq_attr.ioapic_pin = dev->irq;
+	irq_attr.trigger = 1; /* level */
+	irq_attr.polarity = 1; /* active low */
+	io_apic_set_pci_routing(&dev->dev, dev->irq, &irq_attr);
+
+	return 0;
+}
+
+struct pci_ops pci_mrst_ops = {
+	.read = pci_read,
+	.write = pci_write,
+};
+
+/**
+ * pci_mrst_init - installs pci_mrst_ops
+ *
+ * Moorestown has an interesting PCI implementation (see above).
+ * Called when the early platform detection installs it.
+ */
+int __init pci_mrst_init(void)
+{
+	printk(KERN_INFO "Moorestown platform detected, using MRST PCI ops\n");
+	pci_mmcfg_late_init();
+	pcibios_enable_irq = mrst_pci_irq_enable;
+	pci_root_ops = pci_mrst_ops;
+	/* Continue with standard init */
+	return 1;
+}
+
+/*
+ * Langwell devices reside at fixed offsets, don't try to move them.
+ */
+static void __devinit pci_fixed_bar_fixup(struct pci_dev *dev)
+{
+	unsigned long offset;
+	u32 size;
+	int i;
+
+	/* Fixup the BAR sizes for fixed BAR devices and make them unmoveable */
+	offset = fixed_bar_cap(dev->bus, dev->devfn);
+	if (!offset || PCI_DEVFN(2, 0) == dev->devfn ||
+	    PCI_DEVFN(2, 2) == dev->devfn)
+		return;
+
+	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
+		pci_read_config_dword(dev, offset + 8 + (i * 4), &size);
+		dev->resource[i].end = dev->resource[i].start + size - 1;
+		dev->resource[i].flags |= IORESOURCE_PCI_FIXED;
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_fixed_bar_fixup);