bcm53xx: fix hangs in PCIe2 host driver

Accessing CFG regs with no card present results in SoC hang.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

SVN-Revision: 42895
This commit is contained in:
Rafał Miłecki 2014-10-14 08:06:15 +00:00
parent 540a6a45e4
commit 5a03d0c931

View file

@ -48,7 +48,7 @@ Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+obj-$(CONFIG_PCI_BCMA) += pcie2-bcma.o
--- /dev/null
+++ b/drivers/pci/host/pcie2-bcma.c
@@ -0,0 +1,591 @@
@@ -0,0 +1,619 @@
+/*
+ * Northstar PCI-Express driver
+ * Only supports Root-Complex (RC) mode
@ -113,6 +113,8 @@ Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+#define BCM4352_D11AC2G_ID 0x43b2 /* 4352 802.11ac 2.4G device */
+#define BCM4352_D11AC5G_ID 0x43b3 /* 4352 802.11ac 5G device */
+
+static struct pci_ops bcma_pcie2_ops;
+
+static int bcma_pcie2_map_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
+{
+ struct pci_sys_data *sys = pdev->sysdata;
@ -268,11 +270,26 @@ Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+ * Check link status, return 0 if link is up in RC mode,
+ * otherwise return non-zero
+ */
+static int bcma_pcie2_check_link(struct bcma_device *bdev, u32 allow_gen2)
+static int bcma_pcie2_check_link(struct bcma_device *bdev,
+ struct pci_sys_data *sys, u32 allow_gen2)
+{
+ u32 devfn = 0;
+ u8 tmp8;
+ u32 tmp32;
+ u16 tmp16;
+ u8 tmp8;
+ int pos;
+ bool link = false;
+ /*
+ * Setup callback (bcma_pcie2_setup) is called in pcibios_init_hw before
+ * creating bus root, so we don't have it here yet. On the other hand
+ * we really want to use pci_bus_find_capability helper to check NLW.
+ * Let's fake simple pci_bus just to query for capabilities.
+ */
+ struct pci_bus bus = {
+ .number = 0,
+ .ops = &bcma_pcie2_ops,
+ .sysdata = sys,
+ };
+
+ tmp32 = bcma_pcie2_read_config32(bdev, 0, devfn, 0xdc);
+ tmp32 &= ~0xf;
@ -292,7 +309,18 @@ Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+ return -ENODEV;
+ }
+
+ return 0;
+ /* NS PAX only changes NLW field when card is present */
+ pos = pci_bus_find_capability(&bus, devfn, PCI_CAP_ID_EXP);
+ if (pos) {
+ u8 nlw;
+
+ pci_bus_read_config_word(&bus, devfn, pos + PCI_EXP_LNKSTA,
+ &tmp16);
+ nlw = (tmp16 & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT;
+ link = (tmp16 & PCI_EXP_LNKSTA_DLLLA) || nlw != 0;
+ }
+
+ return link ? 0 : -ENODEV;
+}
+
+/*
@ -559,7 +587,7 @@ Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+ * Skip inactive ports -
+ * will need to change this for hot-plugging
+ */
+ linkfail = bcma_pcie2_check_link(bdev, allow_gen2);
+ linkfail = bcma_pcie2_check_link(bdev, sys, allow_gen2);
+ if (linkfail)
+ break;
+