diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-11-14 17:55:03 +1100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-12-14 16:23:57 +0000 |
| commit | f0997a9518145dc5c30963c74f248e8eac10591b (patch) | |
| tree | 6b025a972ebb959949be9e301aefffa2b1700222 | |
| parent | a5c187d92d2ce30315f333b9dff33af832e8b443 (diff) | |
of/base: Fix PowerPC address parsing hack
commit 746c9e9f92dde2789908e51a354ba90a1962a2eb upstream.
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>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
[bwh: Backported to 3.2: use #ifdef because IS_ENABLED() only works for
config symbols that are defined on the current architecture]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | drivers/of/address.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c index 45c1727d5104..53a613f52394 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -333,6 +333,22 @@ static struct of_bus *of_match_bus(struct device_node *np) return NULL; } +static int of_empty_ranges_quirk(void) +{ +#ifdef 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; +#else + return false; +#endif +} + static int of_translate_one(struct device_node *parent, struct of_bus *bus, struct of_bus *pbus, u32 *addr, int na, int ns, int pna, const char *rprop) @@ -358,12 +374,10 @@ 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); |