From d0ff7a1bcfe886cab1a237895b08ac51ecfe10e7 Mon Sep 17 00:00:00 2001
From: Tim Harvey <tharvey@gateworks.com>
Date: Wed, 10 Apr 2019 08:00:47 -0700
Subject: [PATCH 04/12] PCI: add quirk for Gateworks PLX PEX860x switch with
 GPIO PERST#

Gateworks boards use PLX PEX860x switches where downstream ports
have their PERST# driven from the PEX GPIO.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
---
 drivers/pci/quirks.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -25,6 +25,7 @@
 #include <linux/ktime.h>
 #include <linux/mm.h>
 #include <linux/nvme.h>
+#include <linux/of.h>
 #include <linux/platform_data/x86/apple.h>
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
@@ -5787,3 +5788,34 @@ static void nvidia_ion_ahci_fixup(struct
 	pdev->dev_flags |= PCI_DEV_FLAGS_HAS_MSI_MASKING;
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0ab8, nvidia_ion_ahci_fixup);
+
+#ifdef CONFIG_PCI_HOST_THUNDER_PEM
+/*
+ * fixup for PLX PEX8909 bridge to configure GPIO1-7 as output High
+ * as they are used for slots1-7 PERST#
+ */
+static void newport_pciesw_early_fixup(struct pci_dev *dev)
+{
+	u32 dw;
+
+	if (!of_machine_is_compatible("gw,newport"))
+		return;
+
+	if (dev->devfn != 0)
+		return;
+
+	dev_info(&dev->dev, "de-asserting PERST#\n");
+	pci_read_config_dword(dev, 0x62c, &dw);
+	dw |= 0xaaa8; /* GPIO1-7 outputs */
+	pci_write_config_dword(dev, 0x62c, dw);
+
+	pci_read_config_dword(dev, 0x644, &dw);
+	dw |= 0xfe;   /* GPIO1-7 output high */
+	pci_write_config_dword(dev, 0x644, dw);
+
+	msleep(100);
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_PLX, 0x8609, newport_pciesw_early_fixup);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_PLX, 0x8606, newport_pciesw_early_fixup);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_PLX, 0x8604, newport_pciesw_early_fixup);
+#endif /* CONFIG_PCI_HOST_THUNDER_PEM */
