lkml.org 
[lkml]   [2014]   [Apr]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH 3/3] of: Handle node on PPC32 only
Hi Geert,

On Fri, Apr 18, 2014 at 10:04:15AM +0200, Geert Uytterhoeven wrote:
> On Thu, Apr 17, 2014 at 7:42 PM, Leif Lindholm <leif.lindholm@linaro.org> wrote:
> > In order to deal with an firmware bug on a specific ppc32 platform
> > (longtrail), early_init_dt_scan_memory() looks for a node called
> > memory@0 on all platforms. Restrict this quirk to ppc32 kernels only.
>
> This breaks backwards compatibilty with old DTSes (at least on ARM/MIPS,
> where you added the missing property in patches 1 and 2 of the series)?

As Rob said in response to 0/3, the MIPSs would likely not be affected,
since they embed the DT.

> For the Longtrail, I don't care much anymore, as mine died in 2004.
> AFAIK, there have never been many users anyway.

There are still a few mentions of it under arch/powerpc/, so I wouldn't
want to be the one to kill it off...

How about the below v2 3/3 to address the ARM platform?

Regards,

Leif

From 6fa0b837ad71780334eb97d63c507165b6c57add Mon Sep 17 00:00:00 2001
From: Leif Lindholm <leif.lindholm@linaro.org>
Date: Thu, 17 Apr 2014 14:24:47 +0100
Subject: [PATCH] of: arm: powerpc: Restrict memory@0 node handling to
affected platforms

In order to deal with a firmware bug on a specific ppc32 platform
(longtrail), early_init_dt_scan_memory() looks for a node called
memory@0 on all platforms, for all nodes lacking a device_type.
Restrict this quirk to ppc32 and the arm mach-ux500 platforms (one of
which has depended on this special handling).

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
---
arch/arm/mach-ux500/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
drivers/of/Kconfig | 3 +++
drivers/of/fdt.c | 10 +++++++++-
4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-ux500/Kconfig b/arch/arm/mach-ux500/Kconfig
index b41a42d..e6b0c3b 100644
--- a/arch/arm/mach-ux500/Kconfig
+++ b/arch/arm/mach-ux500/Kconfig
@@ -13,6 +13,7 @@ config ARCH_U8500
select CLKSRC_NOMADIK_MTU
select HAVE_ARM_SCU if SMP
select HAVE_ARM_TWD if SMP
+ select OF_MEMORY_AT_0_QUIRK
select PINCTRL
select PINCTRL_ABX500
select PINCTRL_NOMADIK
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e099899..d78452d 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -3,6 +3,7 @@ source "arch/powerpc/platforms/Kconfig.cputype"
config PPC32
bool
default y if !PPC64
+ select OF_MEMORY_AT_0_QUIRK

config 32BIT
bool
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 889005f..230c747 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -77,4 +77,7 @@ config OF_RESERVED_MEM
help
Helpers to allow for reservation of memory regions

+config OF_MEMORY_AT_0_QUIRK
+ def_bool n
+
endmenu # OF
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index fa16a91..1b80b94 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -887,14 +887,22 @@ int __init early_init_dt_scan_memory(unsigned long node, const char *uname,

/* We are scanning "memory" nodes only */
if (type == NULL) {
+#ifdef CONFIG_OF_MEMORY_AT_0_QUIRK
/*
* The longtrail doesn't have a device_type on the
* /memory node, so look for the node called /memory@0.
+ * Converted to generic quirk to handle later platforms
+ * with inforrect DTs that work only because of this
+ * special handling.
*/
if (depth != 1 || strcmp(uname, "memory@0") != 0)
return 0;
- } else if (strcmp(type, "memory") != 0)
+#else
+ return 0;
+#endif
+ } else if (strcmp(type, "memory") != 0) {
return 0;
+ }

reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
if (reg == NULL)
--
1.7.10.4


\
 
 \ /
  Last update: 2014-04-18 15:41    [W:1.102 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site