thunderbolt: Support 1st gen Light Ridge controller

Add support for the 1st gen Light Ridge controller, which is built into
these systems:

iMac12,1 2011 21.5"
iMac12,2 2011 27"
Macmini5,1 2011 i5 2.3 GHz
Macmini5,2 2011 i5 2.5 GHz
Macmini5,3 2011 i7 2.0 GHz
MacBookPro8,1 2011 13"
MacBookPro8,2 2011 15"
MacBookPro8,3 2011 17"
MacBookPro9,1 2012 15"
MacBookPro9,2 2012 13"

Light Ridge (CV82524) was the very first copper Thunderbolt controller,
introduced 2010 alongside its fiber-optic cousin Light Peak (CVL2510).
Consequently the chip suffers from some teething troubles:

- MSI is broken for hotplug signaling on the downstream bridges: The chip
just never sends an interrupt. It requests 32 MSIs for each of its six
bridges and the pcieport driver only allocates one per bridge. However
I've verified that even if 32 MSIs are allocated there's no interrupt
on hotplug. The only option is thus to disable MSI, which is also what
OS X does. Apparently all Thunderbolt chips up to revision 1 of Cactus
Ridge 4C are plagued by this issue so quirk those as well.

- The chip supports a maximum hop_count of 32, unlike its successors
which support only 12. Fixup ring_interrupt_active() to cope with
values >= 32.

- Another peculiarity is that the chip supports a maximum of 13 ports
whereas its successors support 12. However the additional port (#5)
seems to be unusable as reading its TB_CFG_PORT config space results in
TB_CFG_ERROR_INVALID_CONFIG_SPACE. Add a quirk to mark the port
disabled on the root switch, assuming that's necessary on all Macs
using this chip.

Tested-by: Lukas Wunner <[e-mail]> [MacBookPro9,1]
Tested-by: William Brown <[e-mail]> [MacBookPro8,2]
Signed-off-by: Lukas Wunner <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>
Acked-by: Andreas Noever <[e-mail]>

drivers/pci/quirks.c

···
 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_ATI, PCI_ANY_ID,
 			       PCI_CLASS_DISPLAY_VGA, 8, quirk_no_pm_reset);
 
+/*
+ * Thunderbolt controllers with broken MSI hotplug signaling:
+ * Entire 1st generation (Light Ridge, Eagle Ridge, Light Peak) and part
+ * of the 2nd generation (Cactus Ridge 4C up to revision 1, Port Ridge).
+ */
+static void quirk_thunderbolt_hotplug_msi(struct pci_dev *pdev)
+{
+	if (pdev->is_hotplug_bridge &&
+	    (pdev->device != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C ||
+	     pdev->revision <= 1))
+		pdev->no_msi = 1;
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LIGHT_RIDGE,
+			quirk_thunderbolt_hotplug_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EAGLE_RIDGE,
+			quirk_thunderbolt_hotplug_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LIGHT_PEAK,
+			quirk_thunderbolt_hotplug_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C,
+			quirk_thunderbolt_hotplug_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PORT_RIDGE,
+			quirk_thunderbolt_hotplug_msi);
+
 #ifdef CONFIG_ACPI
 /*
  * Apple: Shutdown Cactus Ridge Thunderbolt controller.
···
 	if (!nhi)
 		goto out;
 	if (nhi->vendor != PCI_VENDOR_ID_INTEL
-		    || (nhi->device != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C &&
+		    || (nhi->device != PCI_DEVICE_ID_INTEL_LIGHT_RIDGE &&
+			nhi->device != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C &&
 			nhi->device != PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI)
 		    || nhi->subsystem_vendor != 0x2222
 		    || nhi->subsystem_device != 0x1111)
···
 	pci_dev_put(nhi);
 	pci_dev_put(sibling);
 }
+DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_INTEL,
+			       PCI_DEVICE_ID_INTEL_LIGHT_RIDGE,
+			       quirk_apple_wait_for_thunderbolt);
 DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_INTEL,
 			       PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C,
 			       quirk_apple_wait_for_thunderbolt);

drivers/thunderbolt/eeprom.c

···
 		sw->ports[4].link_nr = 1;
 		sw->ports[3].dual_link_port = &sw->ports[4];
 		sw->ports[4].dual_link_port = &sw->ports[3];
+
+		/* Port 5 is inaccessible on this gen 1 controller */
+		if (sw->config.device_id == PCI_DEVICE_ID_INTEL_LIGHT_RIDGE)
+			sw->ports[5].disabled = true;
+
 		return 0;
 	}
 

drivers/thunderbolt/nhi.c

···
  */
 static void ring_interrupt_active(struct tb_ring *ring, bool active)
 {
-	int reg = REG_RING_INTERRUPT_BASE + ring_interrupt_index(ring) / 32;
+	int reg = REG_RING_INTERRUPT_BASE +
+		  ring_interrupt_index(ring) / 32 * 4;
 	int bit = ring_interrupt_index(ring) & 31;
 	int mask = 1 << bit;
 	u32 old, new;
···
 	/* cannot fail - table is allocated bin pcim_iomap_regions */
 	nhi->iobase = pcim_iomap_table(pdev)[0];
 	nhi->hop_count = ioread32(nhi->iobase + REG_HOP_COUNT) & 0x3ff;
-	if (nhi->hop_count != 12)
+	if (nhi->hop_count != 12 && nhi->hop_count != 32)
 		dev_warn(&pdev->dev, "unexpected hop count: %d\n",
 			 nhi->hop_count);
 	INIT_WORK(&nhi->interrupt_work, nhi_interrupt_work);
···
 	 * We have to specify class, the TB bridges use the same device and
 	 * vendor (sub)id on gen 1 and gen 2 controllers.
 	 */
+	{
+		.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
+		.vendor = PCI_VENDOR_ID_INTEL,
+		.device = PCI_DEVICE_ID_INTEL_LIGHT_RIDGE,
+		.subvendor = 0x2222, .subdevice = 0x1111,
+	},
 	{
 		.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
 		.vendor = PCI_VENDOR_ID_INTEL,

drivers/thunderbolt/switch.c

···
 		tb_sw_warn(sw, "unknown switch vendor id %#x\n",
 			   sw->config.vendor_id);
 
-	if (sw->config.device_id != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C &&
+	if (sw->config.device_id != PCI_DEVICE_ID_INTEL_LIGHT_RIDGE &&
+	    sw->config.device_id != PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C &&
 	    sw->config.device_id != PCI_DEVICE_ID_INTEL_PORT_RIDGE)
 		tb_sw_warn(sw, "unsupported switch device id %#x\n",
 			   sw->config.device_id);