Re: [PATCH 5/5] x86: OLPC: add OLPC device-tree support
From: Grant Likely
Date: Wed Oct 20 2010 - 15:07:23 EST
On Sun, Oct 10, 2010 at 10:13 PM, Grant Likely
<grant.likely@xxxxxxxxxxxx> 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@xxxxxxxxxx>
>
> 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.
>
> 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@xxxxxxxxxxxxx
>> + * Adapted for x86/OLPC by Andres Salomon <dilinger@xxxxxxxxxx>
>> + *
>> + * 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
>>
>
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
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