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authorPhilippe Bergheaud <felix@linux.vnet.ibm.com>2016-07-01 13:32:52 +0200
committerMichael Ellerman <mpe@ellerman.id.au>2016-07-08 22:23:57 +1000
commit3b3dcd61fa4e3604d8f1bdfd8471fca7b7c012e4 (patch)
treeb6affe5c87b114c797f21c04faa97daa56428dbb /drivers/misc/cxl/pci.c
parente00878be3f414a99234b3c9613e2fcab7497cd4b (diff)
cxl: Ignore CAPI adapters misplaced in switched slots
One should not attempt to switch a PHB into CAPI mode if there is a switch between the PHB and the adapter. This patch modifies the cxl driver to ignore CAPI adapters misplaced in switched slots. Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers/misc/cxl/pci.c')
-rw-r--r--drivers/misc/cxl/pci.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index b7f2e96c1528..3a5f9801640d 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -1402,6 +1402,30 @@ static void cxl_pci_remove_adapter(struct cxl *adapter)
device_unregister(&adapter->dev);
}
+#define CXL_MAX_PCIEX_PARENT 2
+
+static int cxl_slot_is_switched(struct pci_dev *dev)
+{
+ struct device_node *np;
+ int depth = 0;
+ const __be32 *prop;
+
+ if (!(np = pci_device_to_OF_node(dev))) {
+ pr_err("cxl: np = NULL\n");
+ return -ENODEV;
+ }
+ of_node_get(np);
+ while (np) {
+ np = of_get_next_parent(np);
+ prop = of_get_property(np, "device_type", NULL);
+ if (!prop || strcmp((char *)prop, "pciex"))
+ break;
+ depth++;
+ }
+ of_node_put(np);
+ return (depth > CXL_MAX_PCIEX_PARENT);
+}
+
static int cxl_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
struct cxl *adapter;
@@ -1413,6 +1437,11 @@ static int cxl_probe(struct pci_dev *dev, const struct pci_device_id *id)
return -ENODEV;
}
+ if (cxl_slot_is_switched(dev)) {
+ dev_info(&dev->dev, "Ignoring card on incompatible PCI slot\n");
+ return -ENODEV;
+ }
+
if (cxl_verbose)
dump_cxl_config_space(dev);