From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Neuendorffer <stephen.neuendorffer-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org>
Subject: RE: [PATCH 3/8] of/fdt: Add unflatten_partial_device_tree
Date: Fri, 23 Jul 2010 15:10:20 -0700
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To: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
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List-Id: devicetree@vger.kernel.org



> -----Original Message-----
> From: glikely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org [mailto:glikely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org] On Behalf Of Gra=
nt Likely
> Sent: Friday, July 16, 2010 12:25 PM
> To: Stephen Neuendorffer
> Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
> Subject: Re: [PATCH 3/8] of/fdt: Add unflatten_partial_device_tree
> =

> On Fri, Jul 16, 2010 at 12:13 PM, Stephen Neuendorffer
> <stephen.neuendorffer-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org> wrote:
> > This code allows a user to parse a partial device tree blob, which is
> > structurally independent of any toplevel blob.
> > Previously, this code assumed that the blob comes from initial_boot_par=
ams.
> > Now, unflatten_partial_device_tree can take a blob from an arbitrary po=
sition,
> > and the location of the blob gets passed around to the various support =
functions.
> >
> > Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org>
> > ---
> > =A0drivers/of/fdt.c =A0 =A0 =A0 | =A0169 ++++++++++++++++++++++++++++++=
+++--------------
> > =A0include/linux/of_fdt.h | =A0 11 ++-
> > =A02 files changed, 126 insertions(+), 54 deletions(-)
> >
> > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> > index d61fda8..89fb1f3 100644
> > --- a/drivers/of/fdt.c
> > +++ b/drivers/of/fdt.c
> > @@ -11,10 +11,12 @@
> >
> > =A0#include <linux/kernel.h>
> > =A0#include <linux/initrd.h>
> > +#include <linux/module.h>
> > =A0#include <linux/of.h>
> > =A0#include <linux/of_fdt.h>
> > =A0#include <linux/string.h>
> > =A0#include <linux/errno.h>
> > +#include <linux/slab.h>
> >
> > =A0#ifdef CONFIG_PPC
> > =A0#include <asm/machdep.h>
> > @@ -22,15 +24,19 @@
> >
> > =A0#include <asm/page.h>
> >
> > -int __initdata dt_root_addr_cells;
> > -int __initdata dt_root_size_cells;
> > +int dt_root_addr_cells;
> > +int dt_root_size_cells;
> =

> The fact that these are still here looks wrong.  The code cannot
> depend on global symbols, particularly global symbols that it
> modified, when it is changed to support processing non-rooted trees.
> More rework will be needed here.

Agreed.  I'll fix it.

> >
> > =A0struct boot_param_header *initial_boot_params;
> >
> > -char *find_flat_dt_string(u32 offset)
> > +void __unflatten_device_tree(unsigned long *blob, struct device_node *=
*mynodes,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsigned long =
(*dt_alloc)(u64 size, u64 align));
> > +
> > +char *find_flat_dt_string(u32 offset,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct boot_param_hea=
der *blob)
> > =A0{
> > - =A0 =A0 =A0 return ((char *)initial_boot_params) +
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(initial_boot_params->off_dt_s=
trings) + offset;
> > + =A0 =A0 =A0 return ((char *)blob) +
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(blob->off_dt_strings) + offse=
t;
> > =A0}
> >
> > =A0/**
> > @@ -118,8 +124,9 @@ unsigned long __init of_get_flat_dt_root(void)
> > =A0* This function can be used within scan_flattened_dt callback to get
> > =A0* access to properties
> > =A0*/
> > -void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsign=
ed long *size)
> > +void * __init of_get_flat_dt_prop(unsigned long node, const char *name,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsign=
ed long *size,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0struct=
 boot_param_header *blob)
> > =A0{
> > =A0 =A0 =A0 =A0unsigned long p =3D node;
> >
> > @@ -140,7 +147,7 @@ void *__init of_get_flat_dt_prop(unsigned long node=
, const char *name,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0if (be32_to_cpu(initial_boot_params->ver=
sion) < 0x10)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0p =3D ALIGN(p, sz >=3D 8=
 ? 8 : 4);
> >
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 nstr =3D find_flat_dt_string(noff);
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 nstr =3D find_flat_dt_string(noff, blob);
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0if (nstr =3D=3D NULL) {
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0pr_warning("Can't find p=
roperty index name !\n");
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return NULL;
> > @@ -160,12 +167,13 @@ void *__init of_get_flat_dt_prop(unsigned long no=
de, const char *name,
> > =A0* @node: node to test
> > =A0* @compat: compatible string to compare with compatible list.
> > =A0*/
> > -int __init of_flat_dt_is_compatible(unsigned long node, const char *co=
mpat)
> > +int =A0of_flat_dt_is_compatible(unsigned long node, const char *compat,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0struct=
 boot_param_header *blob)
> > =A0{
> > =A0 =A0 =A0 =A0const char *cp;
> > =A0 =A0 =A0 =A0unsigned long cplen, l;
> >
> > - =A0 =A0 =A0 cp =3D of_get_flat_dt_prop(node, "compatible", &cplen);
> > + =A0 =A0 =A0 cp =3D of_get_flat_dt_prop(node, "compatible", &cplen, bl=
ob);
> > =A0 =A0 =A0 =A0if (cp =3D=3D NULL)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return 0;
> > =A0 =A0 =A0 =A0while (cplen > 0) {
> > @@ -179,7 +187,7 @@ int __init of_flat_dt_is_compatible(unsigned long n=
ode, const char *compat)
> > =A0 =A0 =A0 =A0return 0;
> > =A0}
> >
> > -static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned lo=
ng size,
> > +static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=
 =A0 unsigned long align)
> > =A0{
> > =A0 =A0 =A0 =A0void *res;
> > @@ -198,11 +206,12 @@ static void *__init unflatten_dt_alloc(unsigned l=
ong *mem, unsigned long size,
> > =A0* @allnextpp: pointer to ->allnext from last allocated device_node
> > =A0* @fpsize: Size of the node path up at the current depth.
> > =A0*/
> > -unsigned long __init unflatten_dt_node(unsigned long mem,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 unsigned long *p,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 struct device_node *dad,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 struct device_node ***allnextpp,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 unsigned long fpsize)
> > +unsigned long unflatten_dt_node(unsigned long mem,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 unsigned =
long *p,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct de=
vice_node *dad,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct de=
vice_node ***allnextpp,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 unsigned =
long fpsize,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct bo=
ot_param_header *blob)
> > =A0{
> > =A0 =A0 =A0 =A0struct device_node *np;
> > =A0 =A0 =A0 =A0struct property *pp, **prev_pp =3D NULL;
> > @@ -298,10 +307,10 @@ unsigned long __init unflatten_dt_node(unsigned l=
ong mem,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0sz =3D be32_to_cpup((__be32 *)(*p));
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0noff =3D be32_to_cpup((__be32 *)((*p) + =
4));
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0*p +=3D 8;
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (be32_to_cpu(initial_boot_params->vers=
ion) < 0x10)
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (be32_to_cpu(blob->version) < 0x10)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0*p =3D ALIGN(*p, sz >=3D=
 8 ? 8 : 4);
> >
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 pname =3D find_flat_dt_string(noff);
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 pname =3D find_flat_dt_string(noff, blob);
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0if (pname =3D=3D NULL) {
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0pr_info("Can't find prop=
erty name in list !\n");
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0break;
> > @@ -380,7 +389,8 @@ unsigned long __init unflatten_dt_node(unsigned lon=
g mem,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0if (tag =3D=3D OF_DT_NOP)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0*p +=3D 4;
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0else
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 mem =3D unflatten_dt_node=
(mem, p, np, allnextpp, fpsize);
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 mem =3D unflatten_dt_node=
(mem, p, np, allnextpp,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 fpsize, blob);
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0tag =3D be32_to_cpup((__be32 *)(*p));
> > =A0 =A0 =A0 =A0}
> > =A0 =A0 =A0 =A0if (tag !=3D OF_DT_END_NODE) {
> > @@ -391,6 +401,8 @@ unsigned long __init unflatten_dt_node(unsigned lon=
g mem,
> > =A0 =A0 =A0 =A0return mem;
> > =A0}
> >
> > +#if defined(CONFIG_MICROBLAZE) || defined(CONFIG_POWERPC) || defined(C=
ONFIG_SPARC)
> > +
> =

> Rather hacky.. There's got to be a better way.  Might be better to add
> a new Kconfig symbol.
> =

> Also, the test is wrong.  ARM is going to want this.  OLPC x86 might
> want it.  SPARC doesn't use it.

I think the right thing is to factor the __init/early related things into a=
 separate file.
Sound reasonable?  Then whoever wants it can select it.

> > =A0#ifdef CONFIG_BLK_DEV_INITRD
> > =A0/**
> > =A0* early_init_dt_check_for_initrd - Decode initrd location from flat =
tree
> > @@ -403,12 +415,14 @@ void __init early_init_dt_check_for_initrd(unsign=
ed long node)
> >
> > =A0 =A0 =A0 =A0pr_debug("Looking for initrd properties... ");
> >
> > - =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "linux,initrd-start", =
&len);
> > + =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "linux,initrd-start",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0&l=
en, initial_boot_params);
> > =A0 =A0 =A0 =A0if (!prop)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return;
> > =A0 =A0 =A0 =A0start =3D of_read_ulong(prop, len/4);
> >
> > - =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "linux,initrd-end", &l=
en);
> > + =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "linux,initrd-end",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0&l=
en, initial_boot_params);
> > =A0 =A0 =A0 =A0if (!prop)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return;
> > =A0 =A0 =A0 =A0end =3D of_read_ulong(prop, len/4);
> > @@ -436,12 +450,14 @@ int __init early_init_dt_scan_root(unsigned long =
node, const char *uname,
> > =A0 =A0 =A0 =A0dt_root_size_cells =3D OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
> > =A0 =A0 =A0 =A0dt_root_addr_cells =3D OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
> >
> > - =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "#size-cells", NULL);
> > + =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "#size-cells",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0NU=
LL, initial_boot_params);
> > =A0 =A0 =A0 =A0if (prop)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0dt_root_size_cells =3D be32_to_cpup(prop=
);
> > =A0 =A0 =A0 =A0pr_debug("dt_root_size_cells =3D %x\n", dt_root_size_cel=
ls);
> >
> > - =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "#address-cells", NULL=
);
> > + =A0 =A0 =A0 prop =3D of_get_flat_dt_prop(node, "#address-cells",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0NU=
LL, initial_boot_params);
> > =A0 =A0 =A0 =A0if (prop)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0dt_root_addr_cells =3D be32_to_cpup(prop=
);
> > =A0 =A0 =A0 =A0pr_debug("dt_root_addr_cells =3D %x\n", dt_root_addr_cel=
ls);
> =

> This is the update to the static globals I was mentioning that must not b=
e done.
> =

> > @@ -450,7 +466,7 @@ int __init early_init_dt_scan_root(unsigned long no=
de, const char *uname,
> > =A0 =A0 =A0 =A0return 1;
> > =A0}
> >
> > -u64 __init dt_mem_next_cell(int s, __be32 **cellp)
> > +u64 =A0dt_mem_next_cell(int s, __be32 **cellp)
> > =A0{
> > =A0 =A0 =A0 =A0__be32 *p =3D *cellp;
> >
> > @@ -464,7 +480,8 @@ u64 __init dt_mem_next_cell(int s, __be32 **cellp)
> > =A0int __init early_init_dt_scan_memory(unsigned long node, const char =
*uname,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=
 int depth, void *data)
> > =A0{
> > - =A0 =A0 =A0 char *type =3D of_get_flat_dt_prop(node, "device_type", N=
ULL);
> > + =A0 =A0 =A0 char *type =3D of_get_flat_dt_prop(node, "device_type",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0NULL, initial_boot_params);
> > =A0 =A0 =A0 =A0__be32 *reg, *endp;
> > =A0 =A0 =A0 =A0unsigned long l;
> >
> > @@ -479,9 +496,10 @@ int __init early_init_dt_scan_memory(unsigned long=
 node, const char *uname,
> > =A0 =A0 =A0 =A0} else if (strcmp(type, "memory") !=3D 0)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return 0;
> >
> > - =A0 =A0 =A0 reg =3D of_get_flat_dt_prop(node, "linux,usable-memory", =
&l);
> > + =A0 =A0 =A0 reg =3D of_get_flat_dt_prop(node, "linux,usable-memory",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 &l, i=
nitial_boot_params);
> > =A0 =A0 =A0 =A0if (reg =3D=3D NULL)
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 reg =3D of_get_flat_dt_prop(node, "reg", =
&l);
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 reg =3D of_get_flat_dt_prop(node, "reg", =
&l, initial_boot_params);
> > =A0 =A0 =A0 =A0if (reg =3D=3D NULL)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return 0;
> >
> > @@ -521,12 +539,12 @@ int __init early_init_dt_scan_chosen(unsigned lon=
g node, const char *uname,
> >
> > =A0 =A0 =A0 =A0early_init_dt_check_for_initrd(node);
> >
> > +#ifdef CONFIG_CMDLINE
> > =A0 =A0 =A0 =A0/* Retreive command line */
> > - =A0 =A0 =A0 p =3D of_get_flat_dt_prop(node, "bootargs", &l);
> > + =A0 =A0 =A0 p =3D of_get_flat_dt_prop(node, "bootargs", &l, initial_b=
oot_params);
> > =A0 =A0 =A0 =A0if (p !=3D NULL && l > 0)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0strlcpy(cmd_line, p, min((int)l, COMMAND=
_LINE_SIZE));
> >
> > -#ifdef CONFIG_CMDLINE
> =

> Why is this being changed?

Because it requires a cmd_line global, which all architectures (especially =
x86) don't seem to have)
Probably if the early stuff get's factored out, then this problem goes away.
 =

> > =A0#ifndef CONFIG_CMDLINE_FORCE
> > =A0 =A0 =A0 =A0if (p =3D=3D NULL || l =3D=3D 0 || (l =3D=3D 1 && (*p) =
=3D=3D 0))
> > =A0#endif
> > @@ -535,12 +553,21 @@ int __init early_init_dt_scan_chosen(unsigned lon=
g node, const char *uname,
> >
> > =A0 =A0 =A0 =A0early_init_dt_scan_chosen_arch(node);
> >
> > +#ifdef CONFIG_CMDLINE
> > =A0 =A0 =A0 =A0pr_debug("Command line is: %s\n", cmd_line);
> > +#endif /* CONFIG_CMDLINE */
> >
> > =A0 =A0 =A0 =A0/* break now */
> > =A0 =A0 =A0 =A0return 1;
> > =A0}
> >
> > +
> > +static unsigned long early_device_tree_alloc(u64 size, u64 align)
> > +{
> > + =A0 =A0 =A0 unsigned long mem =3D early_init_dt_alloc_memory_arch(siz=
e, align);
> > + =A0 =A0 =A0 return (unsigned long) __va(mem);
> > +}
> > +
> > =A0/**
> > =A0* unflatten_device_tree - create tree of device_nodes from flat blob
> > =A0*
> > @@ -551,58 +578,98 @@ int __init early_init_dt_scan_chosen(unsigned lon=
g node, const char *uname,
> > =A0*/
> > =A0void __init unflatten_device_tree(void)
> > =A0{
> > + =A0 =A0 =A0 __unflatten_device_tree(initial_boot_params, &allnodes,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 early_dev=
ice_tree_alloc);
> > +
> > + =A0 =A0 =A0 /* Get pointer to OF "/chosen" node for use everywhere */
> > + =A0 =A0 =A0 of_chosen =3D of_find_node_by_path("/chosen");
> > + =A0 =A0 =A0 if (of_chosen =3D=3D NULL)
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 of_chosen =3D of_find_node_by_path("/chos=
en@0");
> > +}
> > +
> > +#endif
> > +
> > +static unsigned long kernel_tree_alloc(u64 size, u64 align)
> > +{
> > + =A0 =A0 =A0 return (unsigned long) kzalloc(size, GFP_KERNEL);
> > +}
> > +
> > +/**
> > + * unflatten_partial_device_tree - create tree of device_nodes from fl=
at blob
> > + *
> > + * unflattens the device-tree passed by the firmware, creating the
> > + * tree of struct device_node. It also fills the "name" and "type"
> > + * pointers of the nodes so the normal device-tree walking functions
> > + * can be used.
> > + */
> > +void unflatten_partial_device_tree(unsigned long *blob,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0st=
ruct device_node **mynodes)
> > +{
> > + =A0 =A0 =A0 __unflatten_device_tree(blob, mynodes, &kernel_tree_alloc=
);
> > +}
> > +EXPORT_SYMBOL(unflatten_partial_device_tree);
> =

> unflatten_partial_device_tree and unflatten_device_tree should be
> defined *below* __unflatten_device_tree().

Well, I wanted to avoid that, because it made the ordering requirements in =
the file more nasty
and it makes the #ifdefs more complex.

> > +
> > +/**
> > + * __unflatten_device_tree - create tree of device_nodes from flat blob
> > + *
> > + * unflattens the device-tree passed by the firmware, creating the
> > + * tree of struct device_node. It also fills the "name" and "type"
> > + * pointers of the nodes so the normal device-tree walking functions
> > + * can be used. =A0Memory is allocated using the given function.
> > + */
> > +void __unflatten_device_tree(unsigned long *blob, struct device_node *=
*mynodes,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsigned long =
(*dt_alloc)(u64 size, u64 align))
> > +{
> > + =A0 =A0 =A0 struct boot_param_header *device_tree =3D
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 (struct boot_param_header *)blob;
> > =A0 =A0 =A0 =A0unsigned long start, mem, size;
> > - =A0 =A0 =A0 struct device_node **allnextp =3D &allnodes;
> > + =A0 =A0 =A0 struct device_node **allnextp =3D mynodes;
> >
> > =A0 =A0 =A0 =A0pr_debug(" -> unflatten_device_tree()\n");
> >
> > - =A0 =A0 =A0 if (!initial_boot_params) {
> > + =A0 =A0 =A0 if (!device_tree) {
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0pr_debug("No device tree pointer\n");
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return;
> > =A0 =A0 =A0 =A0}
> >
> > =A0 =A0 =A0 =A0pr_debug("Unflattening device tree:\n");
> > - =A0 =A0 =A0 pr_debug("magic: %08x\n", be32_to_cpu(initial_boot_params=
->magic));
> > - =A0 =A0 =A0 pr_debug("size: %08x\n", be32_to_cpu(initial_boot_params-=
>totalsize));
> > - =A0 =A0 =A0 pr_debug("version: %08x\n", be32_to_cpu(initial_boot_para=
ms->version));
> > + =A0 =A0 =A0 pr_debug("magic: %08x\n", be32_to_cpu(device_tree->magic)=
);
> > + =A0 =A0 =A0 pr_debug("size: %08x\n", be32_to_cpu(device_tree->totalsi=
ze));
> > + =A0 =A0 =A0 pr_debug("version: %08x\n", be32_to_cpu(device_tree->vers=
ion));
> >
> > - =A0 =A0 =A0 if (be32_to_cpu(initial_boot_params->magic) !=3D OF_DT_HE=
ADER) {
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 pr_err("Invalid device tree blob header\n=
");
> > + =A0 =A0 =A0 if (be32_to_cpu(device_tree->magic) !=3D OF_DT_HEADER) {
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 pr_err("Invalid device tree blob header %=
x\n",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0be32_to_cpu(device_tree->m=
agic));
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0return;
> > =A0 =A0 =A0 =A0}
> >
> > =A0 =A0 =A0 =A0/* First pass, scan for size */
> > - =A0 =A0 =A0 start =3D ((unsigned long)initial_boot_params) +
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(initial_boot_params->off_dt_s=
truct);
> > - =A0 =A0 =A0 size =3D unflatten_dt_node(0, &start, NULL, NULL, 0);
> > + =A0 =A0 =A0 start =3D ((unsigned long)device_tree) +
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(device_tree->off_dt_struct);
> > + =A0 =A0 =A0 size =3D unflatten_dt_node(0, &start, NULL, NULL, 0, devi=
ce_tree);
> > =A0 =A0 =A0 =A0size =3D (size | 3) + 1;
> >
> > =A0 =A0 =A0 =A0pr_debug(" =A0size is %lx, allocating...\n", size);
> >
> > =A0 =A0 =A0 =A0/* Allocate memory for the expanded device tree */
> > - =A0 =A0 =A0 mem =3D early_init_dt_alloc_memory_arch(size + 4,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 __alignof__(struct device=
_node));
> > - =A0 =A0 =A0 mem =3D (unsigned long) __va(mem);
> > + =A0 =A0 =A0 mem =3D (unsigned long) dt_alloc(size + 4,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 __alignof__(struct device_nod=
e));
> >
> > =A0 =A0 =A0 =A0((__be32 *)mem)[size / 4] =3D cpu_to_be32(0xdeadbeef);
> >
> > =A0 =A0 =A0 =A0pr_debug(" =A0unflattening %lx...\n", mem);
> >
> > =A0 =A0 =A0 =A0/* Second pass, do actual unflattening */
> > - =A0 =A0 =A0 start =3D ((unsigned long)initial_boot_params) +
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(initial_boot_params->off_dt_s=
truct);
> > - =A0 =A0 =A0 unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
> > + =A0 =A0 =A0 start =3D ((unsigned long)device_tree) +
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(device_tree->off_dt_struct);
> > + =A0 =A0 =A0 unflatten_dt_node(mem, &start, NULL, &allnextp, 0, device=
_tree);
> > =A0 =A0 =A0 =A0if (be32_to_cpup((__be32 *)start) !=3D OF_DT_END)
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 pr_warning("Weird tag at end of tree: %08=
x\n", *((u32 *)start));
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 pr_warning("Weird tag at end of tree: %08=
x\n",
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0*((u32 *)start));
> > =A0 =A0 =A0 =A0if (be32_to_cpu(((__be32 *)mem)[size / 4]) !=3D 0xdeadbe=
ef)
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0pr_warning("End of tree marker overwritt=
en: %08x\n",
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 be32_to_cpu(((__be3=
2 *)mem)[size / 4]));
> > =A0 =A0 =A0 =A0*allnextp =3D NULL;
> >
> > - =A0 =A0 =A0 /* Get pointer to OF "/chosen" node for use everywhere */
> > - =A0 =A0 =A0 of_chosen =3D of_find_node_by_path("/chosen");
> > - =A0 =A0 =A0 if (of_chosen =3D=3D NULL)
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 of_chosen =3D of_find_node_by_path("/chos=
en@0");
> > -
> > =A0 =A0 =A0 =A0pr_debug(" <- unflatten_device_tree()\n");
> > =A0}
> > diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> > index 71e1a91..2bc0754 100644
> > --- a/include/linux/of_fdt.h
> > +++ b/include/linux/of_fdt.h
> > @@ -64,13 +64,16 @@ extern int __initdata dt_root_size_cells;
> > =A0extern struct boot_param_header *initial_boot_params;
> >
> > =A0/* For scanning the flat device-tree at boot time */
> > -extern char *find_flat_dt_string(u32 offset);
> > +extern char *find_flat_dt_string(u32 offset,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct boot_param_hea=
der *blob);
> =

> Well, fdt.c is the only user of this.  I think this line can be removed.
> =

> > =A0extern int of_scan_flat_dt(int (*it)(unsigned long node, const char =
*uname,
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=
 int depth, void *data),
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 void *data);
> > =A0extern void *of_get_flat_dt_prop(unsigned long node, const char *nam=
e,
> > - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsign=
ed long *size);
> > -extern int of_flat_dt_is_compatible(unsigned long node, const char *na=
me);
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0unsign=
ed long *size,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct boot_param_hea=
der *blob);
> > +extern int of_flat_dt_is_compatible(unsigned long node, const char *na=
me,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct boot_param_hea=
der *blob);
> =

> Need to fix this.  The prototypes for of_get_flat_dt_prop() and
> of_flat_dt_is_compatible are changed, but there are users in the
> microblaze and powerpc trees which are not updated.

Good point.

> > =A0extern unsigned long of_get_flat_dt_root(void);
> > =A0extern void early_init_dt_scan_chosen_arch(unsigned long node);
> > =A0extern int early_init_dt_scan_chosen(unsigned long node, const char =
*uname,
> > @@ -98,6 +101,8 @@ extern int early_init_dt_scan_root(unsigned long nod=
e, const char *uname,
> >
> > =A0/* Other Prototypes */
> > =A0extern void unflatten_device_tree(void);
> > +extern void unflatten_partial_device_tree(unsigned long *blob,
> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 struct device_node **mynodes);
> > =A0extern void early_init_devtree(void *);
> > =A0#else /* CONFIG_OF_FLATTREE */
> > =A0static inline void unflatten_device_tree(void) {}
> > --
> > 1.5.6.6
> >
> >
> >
> > This email and any attachments are intended for the sole use of the nam=
ed recipient(s) and
> contain(s) confidential information that may be proprietary, privileged o=
r copyrighted under
> applicable law. If you are not the intended recipient, do not read, copy,=
 or forward this email
> message or any attachments. Delete this email message and any attachments=
 immediately.
> >
> >
> >
> =

> =

> =

> --
> Grant Likely, B.Sc., P.Eng.
> Secret Lab Technologies Ltd.


This email and any attachments are intended for the sole use of the named r=
ecipient(s) and contain(s) confidential information that may be proprietary=
, privileged or copyrighted under applicable law. If you are not the intend=
ed recipient, do not read, copy, or forward this email message or any attac=
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