Re: [PATCH 5/5] x86: OLPC: add OLPC device-tree support

[Andres Salomon <dilinger@queued.net>]

On Wed, 20 Oct 2010 12:56:21 -0600
Grant Likely <grant.likely@secretlab.ca> wrote:

> On Sun, Oct 10, 2010 at 10:13 PM, Grant Likely
> <grant.likely@secretlab.ca> wrote:
> > On Sun, Oct 10, 2010 at 02:06:26AM -0700, Andres Salomon wrote:
> >>
> >> Make use of PROC_DEVICETREE to export the tree, and sparc's
> >> PROMTREE code to call into OLPC's Open Firmware to build the tree.
> >>
> >> Signed-off-by: Andres Salomon <dilinger@queued.net>
> >
> > Holding off on this one until I hear from the x86 maintainers
> > [cc'd].
> 
> Oops, and it appears that patch breaks the build on other
> architectures when CONFIG_OF is enabled and CONFIG_PROMTREE is not due
> to how of_pdt_init_devicetree is defined.
> 
> g.
> 

D'oh.  Do you have any preferences for what we should be using here?
Generic OF hook?  PDT-specific hook?  Forget the hook and just call
a PDT function?  I'm leaning towards that last option.


> >
> > g.
> >
> >> ---
> >>  arch/x86/Kconfig                |    2 +
> >>  arch/x86/include/asm/olpc_ofw.h |    4 +
> >>  arch/x86/include/asm/prom.h     |    1 +
> >>  arch/x86/kernel/Makefile        |    1 +
> >>  arch/x86/kernel/olpc_ofw.c      |    8 ++
> >>  arch/x86/kernel/olpc_prom.c     |  152
> >> +++++++++++++++++++++++++++++++++++++++ drivers/of/pdt.c
> >>      |    2 + fs/proc/proc_devtree.c          |    4 +
> >>  include/linux/of_pdt.h          |    1 +
> >>  9 files changed, 175 insertions(+), 0 deletions(-)
> >>  create mode 100644 arch/x86/include/asm/prom.h
> >>  create mode 100644 arch/x86/kernel/olpc_prom.c
> >>
> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> >> index cea0cd9..7d4ef72 100644
> >> --- a/arch/x86/Kconfig
> >> +++ b/arch/x86/Kconfig
> >> @@ -2069,6 +2069,8 @@ config OLPC_OPENFIRMWARE
> >>       bool "Support for OLPC's Open Firmware"
> >>       depends on !X86_64 && !X86_PAE
> >>       default y if OLPC
> >> +     select OF
> >> +     select OF_PROMTREE
> >>       help
> >>         This option adds support for the implementation of Open
> >> Firmware that is used on the OLPC XO-1 Children's Machine.
> >> diff --git a/arch/x86/include/asm/olpc_ofw.h
> >> b/arch/x86/include/asm/olpc_ofw.h index 08fde47..13075df 100644
> >> --- a/arch/x86/include/asm/olpc_ofw.h
> >> +++ b/arch/x86/include/asm/olpc_ofw.h
> >> @@ -28,4 +28,8 @@ static inline void setup_olpc_ofw_pgd(void) { }
> >>
> >>  #endif /* !CONFIG_OLPC_OPENFIRMWARE */
> >>
> >> +#ifdef CONFIG_PROC_DEVICETREE
> >> +extern void olpc_prom_build_devicetree(void);
> >> +#endif /* CONFIG_PROC_DEVICETREE */
> >> +
> >>  #endif /* _ASM_X86_OLPC_OFW_H */
> >> diff --git a/arch/x86/include/asm/prom.h
> >> b/arch/x86/include/asm/prom.h new file mode 100644
> >> index 0000000..b4ec95f
> >> --- /dev/null
> >> +++ b/arch/x86/include/asm/prom.h
> >> @@ -0,0 +1 @@
> >> +/* dummy prom.h; here to make linux/of.h's #includes happy */
> >> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> >> index fedf32a..ced0c9a 100644
> >> --- a/arch/x86/kernel/Makefile
> >> +++ b/arch/x86/kernel/Makefile
> >> @@ -107,6 +107,7 @@ scx200-y                  += scx200_32.o
> >>
> >>  obj-$(CONFIG_OLPC)           += olpc.o
> >>  obj-$(CONFIG_OLPC_OPENFIRMWARE)      += olpc_ofw.o
> >> +obj-$(CONFIG_PROC_DEVICETREE)        += olpc_prom.o
> >>  obj-$(CONFIG_X86_MRST)               += mrst.o
> >>
> >>  microcode-y                          := microcode_core.o
> >> diff --git a/arch/x86/kernel/olpc_ofw.c
> >> b/arch/x86/kernel/olpc_ofw.c index 3218aa7..6c4d243 100644
> >> --- a/arch/x86/kernel/olpc_ofw.c
> >> +++ b/arch/x86/kernel/olpc_ofw.c
> >> @@ -1,5 +1,7 @@
> >>  #include <linux/kernel.h>
> >>  #include <linux/module.h>
> >> +#include <linux/of.h>
> >> +#include <linux/of_pdt.h>
> >>  #include <linux/init.h>
> >>  #include <asm/page.h>
> >>  #include <asm/setup.h>
> >> @@ -38,6 +40,12 @@ void __init setup_olpc_ofw_pgd(void)
> >>       /* implicit optimization barrier here due to uninline
> >> function return */
> >>
> >>       early_iounmap(base, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD);
> >> +
> >> +#ifdef CONFIG_PROC_DEVICETREE
> >> +     /* OFW set up succesfully; use it for the device tree */
> >> +     of_pdt_init_devicetree = olpc_prom_build_devicetree;
> >> +#endif
> >> +
> >>  }
> >>
> >>  int __olpc_ofw(const char *name, int nr_args, const void **args,
> >> int nr_res, diff --git a/arch/x86/kernel/olpc_prom.c
> >> b/arch/x86/kernel/olpc_prom.c new file mode 100644
> >> index 0000000..e2ecaf2
> >> --- /dev/null
> >> +++ b/arch/x86/kernel/olpc_prom.c
> >> @@ -0,0 +1,152 @@
> >> +/*
> >> + * olpc_prom.c: OLPC-specific OFW device tree support code.
> >> + *
> >> + * Paul Mackerras    August 1996.
> >> + * Copyright (C) 1996-2005 Paul Mackerras.
> >> + *
> >> + *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter
> >> Bergner.
> >> + *    {engebret|bergner}@us.ibm.com
> >> + *
> >> + *  Adapted for sparc by David S. Miller davem@davemloft.net
> >> + *  Adapted for x86/OLPC by Andres Salomon <dilinger@queued.net>
> >> + *
> >> + *      This program is free software; you can redistribute it
> >> and/or
> >> + *      modify it under the terms of the GNU General Public
> >> License
> >> + *      as published by the Free Software Foundation; either
> >> version
> >> + *      2 of the License, or (at your option) any later version.
> >> + */
> >> +
> >> +#include <linux/kernel.h>
> >> +#include <linux/module.h>
> >> +#include <linux/errno.h>
> >> +#include <linux/slab.h>
> >> +#include <linux/of.h>
> >> +#include <linux/of_pdt.h>
> >> +#include <asm/olpc_ofw.h>
> >> +
> >> +static phandle __init olpc_prom_getsibling(phandle node)
> >> +{
> >> +     const void *args[] = { (void *)node };
> >> +     void *res[] = { &node };
> >> +
> >> +     if (node = -1)
> >> +             return 0;
> >> +
> >> +     if (olpc_ofw("peer", args, res) || node = -1)
> >> +             return 0;
> >> +
> >> +     return node;
> >> +}
> >> +
> >> +static phandle __init olpc_prom_getchild(phandle node)
> >> +{
> >> +     const void *args[] = { (void *)node };
> >> +     void *res[] = { &node };
> >> +
> >> +     if (node = -1)
> >> +             return 0;
> >> +
> >> +     if (olpc_ofw("child", args, res) || node = -1) {
> >> +             pr_err("PROM: %s: fetching child failed!\n",
> >> __func__);
> >> +             return 0;
> >> +     }
> >> +
> >> +     return node;
> >> +}
> >> +
> >> +static int __init olpc_prom_getproplen(phandle node, const char
> >> *prop) +{
> >> +     const void *args[] = { (void *)node, prop };
> >> +     int len;
> >> +     void *res[] = { &len };
> >> +
> >> +     if (node = -1)
> >> +             return -1;
> >> +
> >> +     if (olpc_ofw("getproplen", args, res)) {
> >> +             pr_err("PROM: %s: getproplen failed!\n", __func__);
> >> +             return -1;
> >> +     }
> >> +
> >> +     return len;
> >> +}
> >> +
> >> +static int __init olpc_prom_getproperty(phandle node, const char
> >> *prop,
> >> +             char *buf, int bufsize)
> >> +{
> >> +     int plen;
> >> +
> >> +     plen = olpc_prom_getproplen(node, prop);
> >> +     if (plen > bufsize || plen < 1)
> >> +             return -1;
> >> +     else {
> >> +             const void *args[] = { (void *)node, prop, buf,
> >> (void *)plen };
> >> +             void *res[] = { &plen };
> >> +
> >> +             if (olpc_ofw("getprop", args, res)) {
> >> +                     pr_err("PROM: %s: getprop failed!\n",
> >> __func__);
> >> +                     return -1;
> >> +             }
> >> +     }
> >> +
> >> +     return plen;
> >> +}
> >> +
> >> +static int __init olpc_prom_nextprop(phandle node, char *prev,
> >> char *buf) +{
> >> +     const void *args[] = { (void *)node, prev, buf };
> >> +     int success;
> >> +     void *res[] = { &success };
> >> +
> >> +     buf[0] = '\0';
> >> +
> >> +     if (node = -1)
> >> +             return -1;
> >> +
> >> +     if (olpc_ofw("nextprop", args, res) || success != 1)
> >> +             return -1;
> >> +
> >> +     return 0;
> >> +}
> >> +
> >> +static int __init olpc_prom_pkg2path(phandle node, char *buf,
> >> +             const int buflen, int *len)
> >> +{
> >> +     const void *args[] = { (void *)node, buf, (void *)buflen };
> >> +     void *res[] = { len };
> >> +
> >> +     if (node = -1)
> >> +             return -1;
> >> +
> >> +     if (olpc_ofw("package-to-path", args, res) || *len < 1)
> >> +             return -1;
> >> +
> >> +     return 0;
> >> +}
> >> +
> >> +void * __init prom_early_alloc(unsigned long size)
> >> +{
> >> +     /* this is called late enough that we can alloc normally */
> >> +     return kzalloc(size, GFP_KERNEL);
> >> +}
> >> +
> >> +static struct of_pdt_ops prom_olpc_ops __initdata = {
> >> +     .nextprop = olpc_prom_nextprop,
> >> +     .getproplen = olpc_prom_getproplen,
> >> +     .getproperty = olpc_prom_getproperty,
> >> +     .getchild = olpc_prom_getchild,
> >> +     .getsibling = olpc_prom_getsibling,
> >> +     .pkg2path = olpc_prom_pkg2path,
> >> +};
> >> +
> >> +void __init olpc_prom_build_devicetree(void)
> >> +{
> >> +     phandle root;
> >> +
> >> +     root = olpc_prom_getsibling(0);
> >> +     if (root < 0) {
> >> +             pr_err("PROM: unable to get root node from OFW!\n");
> >> +             return;
> >> +     }
> >> +     of_pdt_build_devicetree(root, &prom_olpc_ops);
> >> +}
> >> diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
> >> index 28295d0..07e3daa 100644
> >> --- a/drivers/of/pdt.c
> >> +++ b/drivers/of/pdt.c
> >> @@ -29,6 +29,8 @@ static struct of_pdt_ops *of_pdt_prom_ops
> >> __initdata; void __initdata (*of_pdt_build_more)(struct
> >> device_node *dp, struct device_node ***nextp);
> >>
> >> +void __initdata (*of_pdt_init_devicetree)(void);
> >> +
> >>  #if defined(CONFIG_SPARC)
> >>  unsigned int of_pdt_unique_id __initdata;
> >>
> >> diff --git a/fs/proc/proc_devtree.c b/fs/proc/proc_devtree.c
> >> index d9396a4..9779039 100644
> >> --- a/fs/proc/proc_devtree.c
> >> +++ b/fs/proc/proc_devtree.c
> >> @@ -11,6 +11,7 @@
> >>  #include <linux/stat.h>
> >>  #include <linux/string.h>
> >>  #include <linux/of.h>
> >> +#include <linux/of_pdt.h>
> >>  #include <linux/module.h>
> >>  #include <linux/slab.h>
> >>  #include <asm/prom.h>
> >> @@ -228,6 +229,9 @@ void __init proc_device_tree_init(void)
> >>  {
> >>       struct device_node *root;
> >>
> >> +     if (of_pdt_init_devicetree)
> >> +             of_pdt_init_devicetree();
> >> +
> >>       proc_device_tree = proc_mkdir("device-tree", NULL);
> >>       if (proc_device_tree = NULL)
> >>               return;
> >> diff --git a/include/linux/of_pdt.h b/include/linux/of_pdt.h
> >> index c65a18a..5b29aef 100644
> >> --- a/include/linux/of_pdt.h
> >> +++ b/include/linux/of_pdt.h
> >> @@ -38,6 +38,7 @@ extern void *prom_early_alloc(unsigned long
> >> size);
> >>
> >>  /* for building the device tree */
> >>  extern void of_pdt_build_devicetree(phandle root_node, struct
> >> of_pdt_ops *ops); +extern void (*of_pdt_init_devicetree)(void);
> >>
> >>  extern void (*of_pdt_build_more)(struct device_node *dp,
> >>               struct device_node ***nextp);
> >> --
> >> 1.5.6.5
> >>
> >
> 
> 
>