From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965343AbbA1E0V (ORCPT ); Tue, 27 Jan 2015 23:26:21 -0500 Received: from mail.kernel.org ([198.145.29.136]:41381 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965327AbbA1E0R (ORCPT ); Tue, 27 Jan 2015 23:26:17 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , Rob Herring , Zefan Li Subject: [PATCH 3.4 168/177] of/base: Fix PowerPC address parsing hack Date: Wed, 28 Jan 2015 12:10:26 +0800 Message-Id: <1422418236-12852-259-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422418050-12581-1-git-send-email-lizf@kernel.org> References: <1422418050-12581-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Benjamin Herrenschmidt 3.4.106-rc1 review patch. If anyone has any objections, please let me know. ------------------ 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: Zefan Li --- 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 66d96f1..c059ce1 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -328,6 +328,21 @@ 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, u32 *addr, int na, int ns, int pna, const char *rprop) @@ -353,12 +368,10 @@ 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); -- 1.9.1