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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2014-11-14 17:55:03 +1100
committerRob Herring <robh@kernel.org>2014-11-18 11:46:44 -0600
commit746c9e9f92dde2789908e51a354ba90a1962a2eb (patch)
tree5ca9d6602cd4eb71e1d5828b2a52666060a32f05 /drivers
parent9b6eab07588c2de102423fe99c875fc4bfda2508 (diff)
of/base: Fix PowerPC address parsing hack
We have a historical hack that treats missing ranges properties as the equivalent of an empty one. This is needed for ancient PowerMac "bad" device-trees, and shouldn't be enabled for any other PowerPC platform, otherwise we get some nasty layout of devices in sysfs or even duplication when a set of otherwise identically named devices is created multiple times under a different parent node with no ranges property. This fix is needed for the PowerNV i2c busses to be exposed properly and will fix a number of other embedded cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: <stable@vger.kernel.org> Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/of/address.c19
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c
index afdb78299f61..06af494184d6 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -450,6 +450,21 @@ static struct of_bus *of_match_bus(struct device_node *np)
return NULL;
}
+static int of_empty_ranges_quirk(void)
+{
+ if (IS_ENABLED(CONFIG_PPC)) {
+ /* To save cycles, we cache the result */
+ static int quirk_state = -1;
+
+ if (quirk_state < 0)
+ quirk_state =
+ of_machine_is_compatible("Power Macintosh") ||
+ of_machine_is_compatible("MacRISC");
+ return quirk_state;
+ }
+ return false;
+}
+
static int of_translate_one(struct device_node *parent, struct of_bus *bus,
struct of_bus *pbus, __be32 *addr,
int na, int ns, int pna, const char *rprop)
@@ -475,12 +490,10 @@ static int of_translate_one(struct device_node *parent, struct of_bus *bus,
* This code is only enabled on powerpc. --gcl
*/
ranges = of_get_property(parent, rprop, &rlen);
-#if !defined(CONFIG_PPC)
- if (ranges == NULL) {
+ if (ranges == NULL && !of_empty_ranges_quirk()) {
pr_err("OF: no ranges; cannot translate\n");
return 1;
}
-#endif /* !defined(CONFIG_PPC) */
if (ranges == NULL || rlen == 0) {
offset = of_read_number(addr, na);
memset(addr, 0, pna * 4);