Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754091AbaLOPJa (ORCPT ); Mon, 15 Dec 2014 10:09:30 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:38379 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752487AbaLOO1i (ORCPT ); Mon, 15 Dec 2014 09:27:38 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Benjamin Herrenschmidt , Rob Herring , Luis Henriques Subject: [PATCH 3.16.y-ckt 039/168] of/base: Fix PowerPC address parsing hack Date: Mon, 15 Dec 2014 14:24:53 +0000 Message-Id: <1418653622-21105-40-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1418653622-21105-1-git-send-email-luis.henriques@canonical.com> References: <1418653622-21105-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Herrenschmidt 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 Acked-by: Grant Likely Signed-off-by: Rob Herring Signed-off-by: Luis Henriques --- drivers/of/address.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index 5edfcb0da37d..22ce1572af38 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -403,6 +403,21 @@ 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) @@ -428,12 +443,10 @@ 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); -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/