@@ -4210,6 +4210,7 @@ CONFIG_NMI_LOG_BUF_SHIFT=13
# CONFIG_OCFS2_FS is not set
# CONFIG_OCTEONTX2_AF is not set
# CONFIG_OCTEONTX2_PF is not set
+# CONFIG_OF_CONFIGFS is not set
# CONFIG_OF_OVERLAY is not set
CONFIG_OF_RESERVED_MEM=y
# CONFIG_OF_UNITTEST is not set
@@ -23,7 +23,7 @@ Signed-off-by: Imre Kaloz <kaloz@openwrt.org>
{ {0x02, 0x21}, "lz4", unlz4 },
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
-@@ -370,7 +370,7 @@ quiet_cmd_bzip2 = BZIP2 $@
+@@ -374,7 +374,7 @@ quiet_cmd_bzip2 = BZIP2 $@
# ---------------------------------------------------------------------------
quiet_cmd_lzma = LZMA $@
new file mode 100644
@@ -0,0 +1,395 @@
+From 073f612de406b949af513c9ebf4ab0e745ffa969 Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Wed, 4 Dec 2013 19:32:00 +0200
+Subject: [PATCH 01/10] OF: DT-Overlay configfs interface (v7)
+
+Add a runtime interface to using configfs for generic device tree overlay
+usage. With it its possible to use device tree overlays without having
+to use a per-platform overlay manager.
+
+Please see Documentation/devicetree/configfs-overlays.txt for more info.
+
+Changes since v6:
+- Default groups properties API changed.
+
+Changes since v5:
+- New style configfs.
+
+Changes since v4:
+- Loading fix for multiple overlays as found out by
+ Geert Uytterhoeven <geert@linux-m68k.org>
+
+Changes since v3:
+- Fixed compilation on SPARC & Xtensa
+
+Changes since v2:
+- Removed ifdef CONFIG_OF_OVERLAY (since for now it's required)
+- Created a documentation entry
+- Slight rewording in Kconfig
+
+Changes since v1:
+- of_resolve() -> of_resolve_phandles().
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+[geert: Use %zu to format size_t]
+[geert: Rebase to v4.15-rc1]
+[geert: Make cfs_overlay_item_dtbo_{read,write}() and
+ of_cfs_overlay_group static]
+[geert: Let OF_CONFIGFS select OF_FLATTREE to fix sparc all*config]
+[geert: Spelling/grammar s/rationalle of/rationale for/]
+[geert: Rebase on top of commit 39a751a4cb7e4798 ("of: change overlay apply input data from unflattened to FDT")
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+---
+ .../devicetree/configfs-overlays.txt | 31 ++
+ drivers/of/Kconfig | 8 +
+ drivers/of/Makefile | 1 +
+ drivers/of/configfs.c | 284 ++++++++++++++++++
+ 4 files changed, 324 insertions(+)
+ create mode 100644 Documentation/devicetree/configfs-overlays.txt
+ create mode 100644 drivers/of/configfs.c
+
+--- /dev/null
++++ b/Documentation/devicetree/configfs-overlays.txt
+@@ -0,0 +1,31 @@
++Howto use the configfs overlay interface.
++
++A device-tree configfs entry is created in /config/device-tree/overlays
++and and it is manipulated using standard file system I/O.
++Note that this is a debug level interface, for use by developers and
++not necessarily something accessed by normal users due to the
++security implications of having direct access to the kernel's device tree.
++
++* To create an overlay you mkdir the directory:
++
++ # mkdir /config/device-tree/overlays/foo
++
++* Either you echo the overlay firmware file to the path property file.
++
++ # echo foo.dtbo >/config/device-tree/overlays/foo/path
++
++* Or you cat the contents of the overlay to the dtbo file
++
++ # cat foo.dtbo >/config/device-tree/overlays/foo/dtbo
++
++The overlay file will be applied, and devices will be created/destroyed
++as required.
++
++To remove it simply rmdir the directory.
++
++ # rmdir /config/device-tree/overlays/foo
++
++The rationale for the dual interface (firmware & direct copy) is that each is
++better suited to different use patterns. The firmware interface is what's
++intended to be used by hardware managers in the kernel, while the copy interface
++make sense for developers (since it avoids problems with namespaces).
+--- a/drivers/of/Kconfig
++++ b/drivers/of/Kconfig
+@@ -93,6 +93,14 @@ config OF_OVERLAY
+ While this option is selected automatically when needed, you can
+ enable it manually to improve device tree unit test coverage.
+
++config OF_CONFIGFS
++ bool "Device Tree Overlay ConfigFS interface"
++ select CONFIGFS_FS
++ select OF_FLATTREE
++ depends on OF_OVERLAY
++ help
++ Enable a simple user-space driven DT overlay interface.
++
+ config OF_NUMA
+ bool
+
+--- a/drivers/of/Makefile
++++ b/drivers/of/Makefile
+@@ -1,6 +1,7 @@
+ # SPDX-License-Identifier: GPL-2.0
+ obj-y = base.o device.o platform.o property.o
+ obj-$(CONFIG_OF_KOBJ) += kobj.o
++obj-$(CONFIG_OF_CONFIGFS) += configfs.o
+ obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
+ obj-$(CONFIG_OF_FLATTREE) += fdt.o
+ obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
+--- /dev/null
++++ b/drivers/of/configfs.c
+@@ -0,0 +1,281 @@
++/*
++ * Configfs entries for device-tree
++ *
++ * Copyright (C) 2013 - Pantelis Antoniou <panto@antoniou-consulting.com>
++ *
++ * 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/ctype.h>
++#include <linux/cpu.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/of_fdt.h>
++#include <linux/spinlock.h>
++#include <linux/sizes.h>
++#include <linux/slab.h>
++#include <linux/proc_fs.h>
++#include <linux/configfs.h>
++#include <linux/types.h>
++#include <linux/stat.h>
++#include <linux/limits.h>
++#include <linux/file.h>
++#include <linux/vmalloc.h>
++#include <linux/firmware.h>
++
++#include "of_private.h"
++
++struct cfs_overlay_item {
++ struct config_item item;
++
++ char path[PATH_MAX];
++
++ const struct firmware *fw;
++ struct device_node *overlay;
++ int ov_id;
++
++ void *dtbo;
++ int dtbo_size;
++};
++
++static int create_overlay(struct cfs_overlay_item *overlay, const void *blob,
++ size_t size)
++{
++ int err;
++
++ err = of_overlay_fdt_apply(blob, size, &overlay->ov_id);
++ if (err < 0)
++ pr_err("%s: Failed to create overlay (err=%d)\n", __func__,
++ err);
++
++ return err;
++}
++
++static inline struct cfs_overlay_item *to_cfs_overlay_item(
++ struct config_item *item)
++{
++ return item ? container_of(item, struct cfs_overlay_item, item) : NULL;
++}
++
++static ssize_t cfs_overlay_item_path_show(struct config_item *item, char *page)
++{
++ return sprintf(page, "%s\n", to_cfs_overlay_item(item)->path);
++}
++
++static ssize_t cfs_overlay_item_path_store(struct config_item *item,
++ const char *page, size_t count)
++{
++ struct cfs_overlay_item *overlay = to_cfs_overlay_item(item);
++ const char *p = page;
++ char *s;
++ int err;
++
++ /* if it's set do not allow changes */
++ if (overlay->path[0] != '\0' || overlay->dtbo_size > 0)
++ return -EPERM;
++
++ /* copy to path buffer (and make sure it's always zero terminated */
++ count = snprintf(overlay->path, sizeof(overlay->path) - 1, "%s", p);
++ overlay->path[sizeof(overlay->path) - 1] = '\0';
++
++ /* strip trailing newlines */
++ s = overlay->path + strlen(overlay->path);
++ while (s > overlay->path && *--s == '\n')
++ *s = '\0';
++
++ pr_debug("%s: path is '%s'\n", __func__, overlay->path);
++
++ err = request_firmware(&overlay->fw, overlay->path, NULL);
++ if (err != 0)
++ goto out_err;
++
++ err = create_overlay(overlay, overlay->fw->data, overlay->fw->size);
++ if (err < 0)
++ goto out_err;
++
++ return count;
++
++out_err:
++
++ release_firmware(overlay->fw);
++ overlay->fw = NULL;
++
++ overlay->path[0] = '\0';
++ return err;
++}
++
++static ssize_t cfs_overlay_item_status_show(struct config_item *item,
++ char *page)
++{
++ return sprintf(page, "%s\n", to_cfs_overlay_item(item)->ov_id >= 0 ?
++ "applied" : "unapplied");
++}
++
++CONFIGFS_ATTR(cfs_overlay_item_, path);
++CONFIGFS_ATTR_RO(cfs_overlay_item_, status);
++
++static struct configfs_attribute *cfs_overlay_attrs[] = {
++ &cfs_overlay_item_attr_path,
++ &cfs_overlay_item_attr_status,
++ NULL,
++};
++
++static ssize_t cfs_overlay_item_dtbo_read(struct config_item *item, void *buf,
++ size_t max_count)
++{
++ struct cfs_overlay_item *overlay = to_cfs_overlay_item(item);
++
++ pr_debug("%s: buf=%p max_count=%zu\n", __func__,
++ buf, max_count);
++
++ if (overlay->dtbo == NULL)
++ return 0;
++
++ /* copy if buffer provided */
++ if (buf != NULL) {
++ /* the buffer must be large enough */
++ if (overlay->dtbo_size > max_count)
++ return -ENOSPC;
++
++ memcpy(buf, overlay->dtbo, overlay->dtbo_size);
++ }
++
++ return overlay->dtbo_size;
++}
++
++static ssize_t cfs_overlay_item_dtbo_write(struct config_item *item,
++ const void *buf, size_t count)
++{
++ struct cfs_overlay_item *overlay = to_cfs_overlay_item(item);
++ int err;
++
++ /* if it's set do not allow changes */
++ if (overlay->path[0] != '\0' || overlay->dtbo_size > 0)
++ return -EPERM;
++
++ /* copy the contents */
++ overlay->dtbo = kmemdup(buf, count, GFP_KERNEL);
++ if (overlay->dtbo == NULL)
++ return -ENOMEM;
++
++ overlay->dtbo_size = count;
++
++ err = create_overlay(overlay, overlay->dtbo, overlay->dtbo_size);
++ if (err < 0)
++ goto out_err;
++
++ return count;
++
++out_err:
++ kfree(overlay->dtbo);
++ overlay->dtbo = NULL;
++ overlay->dtbo_size = 0;
++
++ return err;
++}
++
++CONFIGFS_BIN_ATTR(cfs_overlay_item_, dtbo, NULL, SZ_1M);
++
++static struct configfs_bin_attribute *cfs_overlay_bin_attrs[] = {
++ &cfs_overlay_item_attr_dtbo,
++ NULL,
++};
++
++static void cfs_overlay_release(struct config_item *item)
++{
++ struct cfs_overlay_item *overlay = to_cfs_overlay_item(item);
++
++ if (overlay->ov_id >= 0)
++ of_overlay_remove(&overlay->ov_id);
++ if (overlay->fw)
++ release_firmware(overlay->fw);
++ /* kfree with NULL is safe */
++ kfree(overlay->dtbo);
++ kfree(overlay);
++}
++
++static struct configfs_item_operations cfs_overlay_item_ops = {
++ .release = cfs_overlay_release,
++};
++
++static struct config_item_type cfs_overlay_type = {
++ .ct_item_ops = &cfs_overlay_item_ops,
++ .ct_attrs = cfs_overlay_attrs,
++ .ct_bin_attrs = cfs_overlay_bin_attrs,
++ .ct_owner = THIS_MODULE,
++};
++
++static struct config_item *cfs_overlay_group_make_item(
++ struct config_group *group, const char *name)
++{
++ struct cfs_overlay_item *overlay;
++
++ overlay = kzalloc(sizeof(*overlay), GFP_KERNEL);
++ if (!overlay)
++ return ERR_PTR(-ENOMEM);
++ overlay->ov_id = -1;
++
++ config_item_init_type_name(&overlay->item, name, &cfs_overlay_type);
++ return &overlay->item;
++}
++
++static void cfs_overlay_group_drop_item(struct config_group *group,
++ struct config_item *item)
++{
++ struct cfs_overlay_item *overlay = to_cfs_overlay_item(item);
++
++ config_item_put(&overlay->item);
++}
++
++static struct configfs_group_operations overlays_ops = {
++ .make_item = cfs_overlay_group_make_item,
++ .drop_item = cfs_overlay_group_drop_item,
++};
++
++static struct config_item_type overlays_type = {
++ .ct_group_ops = &overlays_ops,
++ .ct_owner = THIS_MODULE,
++};
++
++static struct configfs_group_operations of_cfs_ops = {
++ /* empty - we don't allow anything to be created */
++};
++
++static struct config_item_type of_cfs_type = {
++ .ct_group_ops = &of_cfs_ops,
++ .ct_owner = THIS_MODULE,
++};
++
++static struct config_group of_cfs_overlay_group;
++
++static struct configfs_subsystem of_cfs_subsys = {
++ .su_group = {
++ .cg_item = {
++ .ci_namebuf = "device-tree",
++ .ci_type = &of_cfs_type,
++ },
++ },
++ .su_mutex = __MUTEX_INITIALIZER(of_cfs_subsys.su_mutex),
++};
++
++static int __init of_cfs_init(void)
++{
++ int ret;
++
++ config_group_init(&of_cfs_subsys.su_group);
++ config_group_init_type_name(&of_cfs_overlay_group, "overlays",
++ &overlays_type);
++ configfs_add_default_group(&of_cfs_overlay_group,
++ &of_cfs_subsys.su_group);
++
++ ret = configfs_register_subsystem(&of_cfs_subsys);
++ if (ret != 0) {
++ pr_err("%s: failed to register subsys\n", __func__);
++ goto out;
++ }
++out:
++ return ret;
++}
++late_initcall(of_cfs_init);
new file mode 100644
@@ -0,0 +1,157 @@
+From 77ce59e9749c6214f2304fee7d39ac66a2c79bf1 Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Sun, 15 Mar 2015 20:39:36 +0200
+Subject: [PATCH 02/10] of: overlay: kobjectify overlay objects
+
+We are going to need the overlays to appear on sysfs with runtime
+global properties (like master enable) so turn them into kobjects.
+
+They have to be in sysfs so that people can have information about the
+overlays applied in the system, i.e. where their targets are and whether
+removal is possible. In a future more attributes can be added
+in a backwards compatible manner.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+[geert: Rebase to v4.15-rc1]
+[Fengguang Wu: Make overlay_changeset_release() static]
+[geert: Rebase on top of commit 39a751a4cb7e4798 ("of: change overlay apply input data from unflattened to FDT")
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+---
+ drivers/of/base.c | 5 +++++
+ drivers/of/of_private.h | 9 ++++++++
+ drivers/of/overlay.c | 48 +++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 62 insertions(+)
+
+--- a/drivers/of/base.c
++++ b/drivers/of/base.c
+@@ -166,6 +166,7 @@ void __of_phandle_cache_inv_entry(phandl
+ void __init of_core_init(void)
+ {
+ struct device_node *np;
++ int ret;
+
+
+ /* Create the kset, and register existing nodes */
+@@ -186,6 +187,10 @@ void __init of_core_init(void)
+ /* Symlink in /proc as required by userspace ABI */
+ if (of_root)
+ proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
++
++ ret = of_overlay_init();
++ if (ret != 0)
++ pr_warn("of_init: of_overlay_init failed!\n");
+ }
+
+ static struct property *__of_find_property(const struct device_node *np,
+--- a/drivers/of/of_private.h
++++ b/drivers/of/of_private.h
+@@ -169,4 +169,13 @@ static inline int of_dma_get_range(struc
+ }
+ #endif
+
++#if defined(CONFIG_OF_OVERLAY)
++extern int of_overlay_init(void);
++#else
++static inline int of_overlay_init(void)
++{
++ return 0;
++}
++#endif
++
+ #endif /* _LINUX_OF_PRIVATE_H */
+--- a/drivers/of/overlay.c
++++ b/drivers/of/overlay.c
+@@ -20,6 +20,7 @@
+ #include <linux/libfdt.h>
+ #include <linux/err.h>
+ #include <linux/idr.h>
++#include <linux/sysfs.h>
+
+ #include "of_private.h"
+
+@@ -73,6 +74,7 @@ struct overlay_changeset {
+ struct fragment *fragments;
+ bool symbols_fragment;
+ struct of_changeset cset;
++ struct kobject kobj;
+ };
+
+ /* flags are sticky - once set, do not reset */
+@@ -860,6 +862,18 @@ static void free_overlay_changeset(struc
+ of_node_put(ovcs->fragments[i].overlay);
+ }
+ kfree(ovcs->fragments);
++ kobject_put(&ovcs->kobj);
++}
++
++static inline struct overlay_changeset *kobj_to_ovcs(struct kobject *kobj)
++{
++ return container_of(kobj, struct overlay_changeset, kobj);
++}
++
++static void overlay_changeset_release(struct kobject *kobj)
++{
++ struct overlay_changeset *ovcs = kobj_to_ovcs(kobj);
++
+ /*
+ * There should be no live pointers into ovcs->overlay_tree and
+ * ovcs->fdt due to the policy that overlay notifiers are not allowed
+@@ -870,6 +884,12 @@ static void free_overlay_changeset(struc
+ kfree(ovcs);
+ }
+
++static struct kobj_type overlay_changeset_ktype = {
++ .release = overlay_changeset_release,
++};
++
++static struct kset *ov_kset;
++
+ /*
+ * internal documentation
+ *
+@@ -940,6 +960,8 @@ static int of_overlay_apply(const void *
+ goto out;
+ }
+
++ kobject_init(&ovcs->kobj, &overlay_changeset_ktype);
++
+ of_overlay_mutex_lock();
+ mutex_lock(&of_mutex);
+
+@@ -977,6 +999,22 @@ static int of_overlay_apply(const void *
+ goto err_free_overlay_changeset;
+ }
+
++ ovcs->kobj.kset = ov_kset;
++ ret = kobject_add(&ovcs->kobj, NULL, "%d", ovcs->id);
++ if (ret != 0) {
++ pr_err("%s: kobject_add() failed for tree@%s\n", __func__,
++ tree->full_name);
++ ret_tmp = 0;
++ ret_revert = __of_changeset_revert_entries(&ovcs->cset,
++ &ret_tmp);
++ if (ret_revert) {
++ pr_debug("overlay changeset revert error %d\n",
++ ret_revert);
++ devicetree_state_flags |= DTSF_REVERT_FAIL;
++ }
++ goto err_free_overlay_changeset;
++ }
++
+ ret = __of_changeset_apply_notify(&ovcs->cset);
+ if (ret)
+ pr_err("overlay apply changeset entry notify error %d\n", ret);
+@@ -1276,3 +1314,13 @@ int of_overlay_remove_all(void)
+ return 0;
+ }
+ EXPORT_SYMBOL_GPL(of_overlay_remove_all);
++
++/* called from of_init() */
++int of_overlay_init(void)
++{
++ ov_kset = kset_create_and_add("overlays", NULL, &of_kset->kobj);
++ if (!ov_kset)
++ return -ENOMEM;
++
++ return 0;
++}
new file mode 100644
@@ -0,0 +1,105 @@
+From 2d02a48f61ad600a0d26ae066f8ffa2ba789340f Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Tue, 17 Mar 2015 15:25:46 +0200
+Subject: [PATCH 03/10] of: overlay: global sysfs enable attribute
+
+A throw once master enable switch to protect against any
+further overlay applications if the administrator desires so.
+
+A kernel command line option is provided as well.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+---
+ drivers/of/overlay.c | 51 +++++++++++++++++++++++++++++++++++++++++++-
+ 1 file changed, 50 insertions(+), 1 deletion(-)
+
+--- a/drivers/of/overlay.c
++++ b/drivers/of/overlay.c
+@@ -21,6 +21,7 @@
+ #include <linux/err.h>
+ #include <linux/idr.h>
+ #include <linux/sysfs.h>
++#include <linux/atomic.h>
+
+ #include "of_private.h"
+
+@@ -77,6 +78,16 @@ struct overlay_changeset {
+ struct kobject kobj;
+ };
+
++/* master enable switch; once set to 0 can't be re-enabled */
++static atomic_t ov_enable = ATOMIC_INIT(1);
++
++static int __init of_overlay_disable_setup(char *str __always_unused)
++{
++ atomic_set(&ov_enable, 0);
++ return 1;
++}
++__setup("of_overlay_disable", of_overlay_disable_setup);
++
+ /* flags are sticky - once set, do not reset */
+ static int devicetree_state_flags;
+ #define DTSF_APPLY_FAIL 0x01
+@@ -884,6 +895,35 @@ static void overlay_changeset_release(st
+ kfree(ovcs);
+ }
+
++static ssize_t enable_show(struct kobject *kobj,
++ struct kobj_attribute *attr, char *buf)
++{
++ return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&ov_enable));
++}
++
++static ssize_t enable_store(struct kobject *kobj,
++ struct kobj_attribute *attr, const char *buf, size_t count)
++{
++ int ret;
++ bool new_enable;
++
++ ret = strtobool(buf, &new_enable);
++ if (ret != 0)
++ return ret;
++ /* if we've disabled it, no going back */
++ if (atomic_read(&ov_enable) == 0)
++ return -EPERM;
++ atomic_set(&ov_enable, (int)new_enable);
++ return count;
++}
++
++static struct kobj_attribute enable_attr = __ATTR_RW(enable);
++
++static const struct attribute *overlay_global_attrs[] = {
++ &enable_attr.attr,
++ NULL
++};
++
+ static struct kobj_type overlay_changeset_ktype = {
+ .release = overlay_changeset_release,
+ };
+@@ -944,6 +984,10 @@ static int of_overlay_apply(const void *
+ * overlay changeset code is responsible for freeing them.
+ */
+
++ /* administratively disabled */
++ if (!atomic_read(&ov_enable))
++ return -EPERM;
++
+ if (devicetree_corrupt()) {
+ pr_err("devicetree state suspect, refuse to apply overlay\n");
+ kfree(fdt);
+@@ -1318,9 +1362,14 @@ EXPORT_SYMBOL_GPL(of_overlay_remove_all)
+ /* called from of_init() */
+ int of_overlay_init(void)
+ {
++ int rc;
++
+ ov_kset = kset_create_and_add("overlays", NULL, &of_kset->kobj);
+ if (!ov_kset)
+ return -ENOMEM;
+
+- return 0;
++ rc = sysfs_create_files(&ov_kset->kobj, overlay_global_attrs);
++ WARN(rc, "%s: error adding global attributes\n", __func__);
++
++ return rc;
+ }
new file mode 100644
@@ -0,0 +1,40 @@
+From 5b049c3791da89d37bc641ababdcb17359460ca4 Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Tue, 17 Mar 2015 21:42:10 +0200
+Subject: [PATCH 04/10] Documentation: ABI: overlays - global attributes
+
+Documentation ABI entry for overlays sysfs entries.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+---
+ .../sysfs-firmware-devicetree-overlays | 24 +++++++++++++++++++
+ 1 file changed, 24 insertions(+)
+ create mode 100644 Documentation/ABI/testing/sysfs-firmware-devicetree-overlays
+
+--- /dev/null
++++ b/Documentation/ABI/testing/sysfs-firmware-devicetree-overlays
+@@ -0,0 +1,24 @@
++What: /sys/firmware/devicetree/overlays/
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ This directory contains the applied device tree overlays of
++ the running system, as directories of the overlay id.
++
++What: /sys/firmware/devicetree/overlays/enable
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ The master enable switch, by default is 1, and when
++ set to 0 it cannot be re-enabled for security reasons.
++
++ The discussion about this switch takes place in:
++ http://comments.gmane.org/gmane.linux.drivers.devicetree/101871
++
++ Kees Cook:
++ "Coming from the perspective of drawing a bright line between
++ kernel and the root user (which tends to start with disabling
++ kernel module loading), I would say that there at least needs
++ to be a high-level one-way "off" switch for the interface so
++ that systems that have this interface can choose to turn it off
++ during initial boot, etc."
new file mode 100644
@@ -0,0 +1,23 @@
+From 4abe0d08fbeb98e385373379b99783ca0749e5ea Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Thu, 22 Oct 2015 22:37:06 +0300
+Subject: [PATCH 05/10] Documentation: document of_overlay_disable parameter
+
+Document the of_overlay_disable parameter.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+---
+ Documentation/admin-guide/kernel-parameters.txt | 2 ++
+ 1 file changed, 2 insertions(+)
+
+--- a/Documentation/admin-guide/kernel-parameters.txt
++++ b/Documentation/admin-guide/kernel-parameters.txt
+@@ -3441,6 +3441,8 @@
+ This can be set from sysctl after boot.
+ See Documentation/admin-guide/sysctl/vm.rst for details.
+
++ of_overlay_disable [OF] Disable device tree overlays at boot time.
++
+ ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
+ See Documentation/core-api/debugging-via-ohci1394.rst for more
+ info.
new file mode 100644
@@ -0,0 +1,243 @@
+From 2de7bb11c440f0116ce0ab25286b66faf6016984 Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Thu, 23 Apr 2015 19:02:16 +0300
+Subject: [PATCH 06/10] of: overlay: add per overlay sysfs attributes
+
+* A per overlay can_remove sysfs attribute that reports whether
+the overlay can be removed or not due to another overlapping overlay.
+
+* A target sysfs attribute listing the target of each fragment,
+in a group named after the name of the fragment.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+[geert: Setup ovinfo[cnt].info for symbols]
+[geert: Spelling s/changset/changeset/]
+[geert: Rebase on top of commit 39a751a4cb7e4798 ("of: change overlay apply input data from unflattened to FDT")
+[geert: Use "%pOF" instead of of_node_full_name()]
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+---
+ drivers/of/overlay.c | 111 +++++++++++++++++++++++++++++++++++++++----
+ 1 file changed, 101 insertions(+), 10 deletions(-)
+
+--- a/drivers/of/overlay.c
++++ b/drivers/of/overlay.c
+@@ -25,6 +25,20 @@
+
+ #include "of_private.h"
+
++/* fwd. decl */
++struct overlay_changeset;
++struct fragment;
++
++/* an attribute for each fragment */
++struct fragment_attribute {
++ struct attribute attr;
++ ssize_t (*show)(struct kobject *kobj, struct fragment_attribute *fattr,
++ char *buf);
++ ssize_t (*store)(struct kobject *kobj, struct fragment_attribute *fattr,
++ const char *buf, size_t count);
++ struct fragment *fragment;
++};
++
+ /**
+ * struct target - info about current target node as recursing through overlay
+ * @np: node where current level of overlay will be applied
+@@ -47,12 +61,18 @@ struct target {
+
+ /**
+ * struct fragment - info about fragment nodes in overlay expanded device tree
++ * @info: info node that contains the target and overlay
+ * @target: target of the overlay operation
+ * @overlay: pointer to the __overlay__ node
+ */
+ struct fragment {
+ struct device_node *overlay;
+ struct device_node *target;
++ struct overlay_changeset *ovcs;
++ struct device_node *info;
++ struct attribute_group attr_group;
++ struct attribute *attrs[2];
++ struct fragment_attribute target_attr;
+ };
+
+ /**
+@@ -73,6 +93,7 @@ struct overlay_changeset {
+ struct device_node *overlay_tree;
+ int count;
+ struct fragment *fragments;
++ const struct attribute_group **attr_groups;
+ bool symbols_fragment;
+ struct of_changeset cset;
+ struct kobject kobj;
+@@ -106,6 +127,7 @@ static int devicetree_corrupt(void)
+
+ static int build_changeset_next_level(struct overlay_changeset *ovcs,
+ struct target *target, const struct device_node *overlay_node);
++static int overlay_removal_is_ok(struct overlay_changeset *ovcs);
+
+ /*
+ * of_resolve_phandles() finds the largest phandle in the live tree.
+@@ -729,6 +751,16 @@ static struct device_node *find_target(s
+ return NULL;
+ }
+
++static ssize_t target_show(struct kobject *kobj,
++ struct fragment_attribute *fattr, char *buf)
++{
++ struct fragment *fragment = fattr->fragment;
++
++ return snprintf(buf, PAGE_SIZE, "%pOF\n", fragment->target);
++}
++
++static const struct fragment_attribute target_template_attr = __ATTR_RO(target);
++
+ /**
+ * init_overlay_changeset() - initialize overlay changeset from overlay tree
+ * @ovcs: Overlay changeset to build
+@@ -748,7 +780,7 @@ static int init_overlay_changeset(struct
+ struct device_node *node, *overlay_node;
+ struct fragment *fragment;
+ struct fragment *fragments;
+- int cnt, id, ret;
++ int i, cnt, id, ret;
+
+ /*
+ * Warn for some issues. Can not return -EINVAL for these until
+@@ -813,6 +845,7 @@ static int init_overlay_changeset(struct
+ goto err_free_fragments;
+ }
+
++ fragment->info = of_node_get(node);
+ cnt++;
+ }
+
+@@ -833,6 +866,7 @@ static int init_overlay_changeset(struct
+ goto err_free_fragments;
+ }
+
++ fragment->info = of_node_get(node);
+ cnt++;
+ }
+
+@@ -846,6 +880,34 @@ static int init_overlay_changeset(struct
+ ovcs->count = cnt;
+ ovcs->fragments = fragments;
+
++ ovcs->attr_groups = kcalloc(cnt + 1, sizeof(struct attribute_group *),
++ GFP_KERNEL);
++ if (ovcs->attr_groups == NULL) {
++ ret = -ENOMEM;
++ goto err_free_fragments;
++ }
++
++ for (i = 0; i < cnt; i++) {
++ fragment = &ovcs->fragments[i];
++
++ ovcs->attr_groups[i] = &fragment->attr_group;
++
++ fragment->target_attr = target_template_attr;
++ /* make lockdep happy */
++ sysfs_attr_init(&fragment->target_attr.attr);
++ fragment->target_attr.fragment = fragment;
++
++ fragment->attrs[0] = &fragment->target_attr.attr;
++ fragment->attrs[1] = NULL;
++
++ /* NOTE: direct reference to the full_name */
++ fragment->attr_group.name =
++ kbasename(fragment->info->full_name);
++ fragment->attr_group.attrs = fragment->attrs;
++
++ }
++ ovcs->attr_groups[i] = NULL;
++
+ return 0;
+
+ err_free_fragments:
+@@ -868,9 +930,12 @@ static void free_overlay_changeset(struc
+ if (ovcs->id)
+ idr_remove(&ovcs_idr, ovcs->id);
+
++ kfree(ovcs->attr_groups);
++
+ for (i = 0; i < ovcs->count; i++) {
+ of_node_put(ovcs->fragments[i].target);
+ of_node_put(ovcs->fragments[i].overlay);
++ of_node_put(ovcs->fragments[i].info);
+ }
+ kfree(ovcs->fragments);
+ kobject_put(&ovcs->kobj);
+@@ -924,8 +989,25 @@ static const struct attribute *overlay_g
+ NULL
+ };
+
++static ssize_t can_remove_show(struct kobject *kobj,
++ struct kobj_attribute *attr, char *buf)
++{
++ struct overlay_changeset *ovcs = kobj_to_ovcs(kobj);
++
++ return snprintf(buf, PAGE_SIZE, "%d\n", overlay_removal_is_ok(ovcs));
++}
++
++static struct kobj_attribute can_remove_attr = __ATTR_RO(can_remove);
++
++static struct attribute *overlay_changeset_attrs[] = {
++ &can_remove_attr.attr,
++ NULL
++};
++
+ static struct kobj_type overlay_changeset_ktype = {
+ .release = overlay_changeset_release,
++ .sysfs_ops = &kobj_sysfs_ops, /* default kobj sysfs ops */
++ .default_attrs = overlay_changeset_attrs,
+ };
+
+ static struct kset *ov_kset;
+@@ -1048,15 +1130,14 @@ static int of_overlay_apply(const void *
+ if (ret != 0) {
+ pr_err("%s: kobject_add() failed for tree@%s\n", __func__,
+ tree->full_name);
+- ret_tmp = 0;
+- ret_revert = __of_changeset_revert_entries(&ovcs->cset,
+- &ret_tmp);
+- if (ret_revert) {
+- pr_debug("overlay changeset revert error %d\n",
+- ret_revert);
+- devicetree_state_flags |= DTSF_REVERT_FAIL;
+- }
+- goto err_free_overlay_changeset;
++ goto err_revert;
++ }
++
++ ret = sysfs_create_groups(&ovcs->kobj, ovcs->attr_groups);
++ if (ret != 0) {
++ pr_err("%s: sysfs_create_groups() failed for tree@%s\n",
++ __func__, tree->full_name);
++ goto err_revert;
+ }
+
+ ret = __of_changeset_apply_notify(&ovcs->cset);
+@@ -1077,6 +1158,14 @@ static int of_overlay_apply(const void *
+
+ goto out_unlock;
+
++err_revert:
++ ret_tmp = 0;
++ ret_revert = __of_changeset_revert_entries(&ovcs->cset, &ret_tmp);
++ if (ret_revert) {
++ pr_debug("overlay changeset revert error %d\n", ret_revert);
++ devicetree_state_flags |= DTSF_REVERT_FAIL;
++ }
++
+ err_free_tree:
+ kfree(fdt);
+ kfree(tree);
+@@ -1301,6 +1390,8 @@ int of_overlay_remove(int *ovcs_id)
+
+ list_del(&ovcs->ovcs_list);
+
++ sysfs_remove_groups(&ovcs->kobj, ovcs->attr_groups);
++
+ ret_apply = 0;
+ ret = __of_changeset_revert_entries(&ovcs->cset, &ret_apply);
+ if (ret) {
new file mode 100644
@@ -0,0 +1,46 @@
+From a85092f9d149e00510cce1885655dc9084a62f9b Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Thu, 22 Oct 2015 20:59:27 +0300
+Subject: [PATCH 07/10] Documentation: ABI: overlays - per overlay docs
+
+Documentation for the per-overlay attributes.
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+---
+ .../sysfs-firmware-devicetree-overlays | 28 +++++++++++++++++++
+ 1 file changed, 28 insertions(+)
+
+--- a/Documentation/ABI/testing/sysfs-firmware-devicetree-overlays
++++ b/Documentation/ABI/testing/sysfs-firmware-devicetree-overlays
+@@ -22,3 +22,31 @@ Description:
+ to be a high-level one-way "off" switch for the interface so
+ that systems that have this interface can choose to turn it off
+ during initial boot, etc."
++
++What: /sys/firmware/devicetree/overlays/<id>
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ Each directory represents an applied overlay, containing
++ the following attribute files.
++
++What: /sys/firmware/devicetree/overlays/<id>/can_remove
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ The attribute set to 1 means that the overlay can be removed,
++ while 0 means that the overlay is being overlapped therefore
++ removal is prohibited.
++
++What: /sys/firmware/devicetree/overlays/<id>/<fragment-name>/
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ Each of these directories contain information about of the
++ particular overlay fragment.
++
++What: /sys/firmware/devicetree/overlays/<id>/<fragment-name>/target
++Date: October 2015
++Contact: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
++Description:
++ The full-path of the target of the fragment
new file mode 100644
@@ -0,0 +1,150 @@
+From 7e2d9ac81a7abb2a9d8a75c045c0adb357bbf403 Mon Sep 17 00:00:00 2001
+From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+Date: Wed, 14 Oct 2015 13:20:54 +0300
+Subject: [PATCH 08/10] of: rename *_node_sysfs to _node_post
+
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+[geert: Convert new user in of_unittest_overlay_high_level()]
+[geert: Rebase to v4.15-rc1]
+[geert: Rebase on top of commit 39a751a4cb7e4798 ("of: change overlay apply input data from unflattened to FDT")
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+---
+ drivers/of/base.c | 2 +-
+ drivers/of/dynamic.c | 8 ++++----
+ drivers/of/kobj.c | 4 ++--
+ drivers/of/of_private.h | 12 ++++++------
+ drivers/of/unittest.c | 6 +++---
+ 5 files changed, 16 insertions(+), 16 deletions(-)
+
+--- a/drivers/of/base.c
++++ b/drivers/of/base.c
+@@ -178,7 +178,7 @@ void __init of_core_init(void)
+ return;
+ }
+ for_each_of_allnodes(np) {
+- __of_attach_node_sysfs(np);
++ __of_attach_node_post(np);
+ if (np->phandle && !phandle_cache[of_phandle_cache_hash(np->phandle)])
+ phandle_cache[of_phandle_cache_hash(np->phandle)] = np;
+ }
+--- a/drivers/of/dynamic.c
++++ b/drivers/of/dynamic.c
+@@ -243,7 +243,7 @@ int of_attach_node(struct device_node *n
+ __of_attach_node(np);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+- __of_attach_node_sysfs(np);
++ __of_attach_node_post(np);
+ mutex_unlock(&of_mutex);
+
+ of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, &rd);
+@@ -295,7 +295,7 @@ int of_detach_node(struct device_node *n
+ __of_detach_node(np);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+- __of_detach_node_sysfs(np);
++ __of_detach_node_post(np);
+ mutex_unlock(&of_mutex);
+
+ of_reconfig_notify(OF_RECONFIG_DETACH_NODE, &rd);
+@@ -634,10 +634,10 @@ static int __of_changeset_entry_apply(st
+
+ switch (ce->action) {
+ case OF_RECONFIG_ATTACH_NODE:
+- __of_attach_node_sysfs(ce->np);
++ __of_attach_node_post(ce->np);
+ break;
+ case OF_RECONFIG_DETACH_NODE:
+- __of_detach_node_sysfs(ce->np);
++ __of_detach_node_post(ce->np);
+ break;
+ case OF_RECONFIG_ADD_PROPERTY:
+ /* ignore duplicate names */
+--- a/drivers/of/kobj.c
++++ b/drivers/of/kobj.c
+@@ -112,7 +112,7 @@ void __of_update_property_sysfs(struct d
+ __of_add_property_sysfs(np, newprop);
+ }
+
+-int __of_attach_node_sysfs(struct device_node *np)
++int __of_attach_node_post(struct device_node *np)
+ {
+ const char *name;
+ struct kobject *parent;
+@@ -146,7 +146,7 @@ int __of_attach_node_sysfs(struct device
+ return 0;
+ }
+
+-void __of_detach_node_sysfs(struct device_node *np)
++void __of_detach_node_post(struct device_node *np)
+ {
+ struct property *pp;
+
+--- a/drivers/of/of_private.h
++++ b/drivers/of/of_private.h
+@@ -63,8 +63,8 @@ int __of_add_property_sysfs(struct devic
+ void __of_remove_property_sysfs(struct device_node *np, struct property *prop);
+ void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+ struct property *oldprop);
+-int __of_attach_node_sysfs(struct device_node *np);
+-void __of_detach_node_sysfs(struct device_node *np);
++int __of_attach_node_post(struct device_node *np);
++void __of_detach_node_post(struct device_node *np);
+ #else
+ static inline int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+ {
+@@ -73,11 +73,11 @@ static inline int __of_add_property_sysf
+ static inline void __of_remove_property_sysfs(struct device_node *np, struct property *prop) {}
+ static inline void __of_update_property_sysfs(struct device_node *np,
+ struct property *newprop, struct property *oldprop) {}
+-static inline int __of_attach_node_sysfs(struct device_node *np)
++static inline int __of_attach_node_post(struct device_node *np)
+ {
+ return 0;
+ }
+-static inline void __of_detach_node_sysfs(struct device_node *np) {}
++static inline void __of_detach_node_post(struct device_node *np) {}
+ #endif
+
+ #if defined(CONFIG_OF_RESOLVE)
+@@ -135,9 +135,9 @@ extern int __of_update_property(struct d
+ extern void __of_update_property_sysfs(struct device_node *np,
+ struct property *newprop, struct property *oldprop);
+
+-extern int __of_attach_node_sysfs(struct device_node *np);
++extern int __of_attach_node_post(struct device_node *np);
+ extern void __of_detach_node(struct device_node *np);
+-extern void __of_detach_node_sysfs(struct device_node *np);
++extern void __of_detach_node_post(struct device_node *np);
+
+ extern void __of_sysfs_remove_bin_file(struct device_node *np,
+ struct property *prop);
+--- a/drivers/of/unittest.c
++++ b/drivers/of/unittest.c
+@@ -1391,7 +1391,7 @@ static void attach_node_and_children(str
+ of_node_clear_flag(np, OF_DETACHED);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+- __of_attach_node_sysfs(np);
++ __of_attach_node_post(np);
+ mutex_unlock(&of_mutex);
+
+ while (child) {
+@@ -1451,7 +1451,7 @@ static int __init unittest_data_add(void
+ if (!of_root) {
+ of_root = unittest_data_node;
+ for_each_of_allnodes(np)
+- __of_attach_node_sysfs(np);
++ __of_attach_node_post(np);
+ of_aliases = of_find_node_by_path("/aliases");
+ of_chosen = of_find_node_by_path("/chosen");
+ of_overlay_mutex_unlock();
+@@ -3115,7 +3115,7 @@ static __init void of_unittest_overlay_h
+ of_root->child = overlay_base_root->child;
+
+ for_each_of_allnodes_from(overlay_base_root, np)
+- __of_attach_node_sysfs(np);
++ __of_attach_node_post(np);
+
+ if (of_symbols) {
+ struct property *new_prop;
new file mode 100644
@@ -0,0 +1,27 @@
+From 09df105083529259874de93f00abc86cb9223b5e Mon Sep 17 00:00:00 2001
+From: Geert Uytterhoeven <geert+renesas@glider.be>
+Date: Wed, 26 Aug 2015 19:21:00 +0200
+Subject: [PATCH 09/10] kbuild: Enable DT symbols when CONFIG_OF_OVERLAY is
+ used
+
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+---
+Replacement for "ARM: DT: Enable symbols when CONFIG_OF_OVERLAY is
+used".
+---
+ scripts/Makefile.lib | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+--- a/scripts/Makefile.lib
++++ b/scripts/Makefile.lib
+@@ -315,6 +315,10 @@ cmd_dt_S_dtb= \
+ $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
+ $(call if_changed,dt_S_dtb)
+
++ifeq ($(CONFIG_OF_OVERLAY),y)
++DTC_FLAGS += -@
++endif
++
+ quiet_cmd_dtc = DTC $@
+ cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
+ $(DTC) -O $(patsubst .%,%,$(suffix $@)) -o $@ -b 0 \
Import patchset allowing loading and applying device tree overlays at run-time via configfs. This will allow for packaging DTOs for hardware add-ons such as the various HATs (Hardware Attached on Top) common for SBCs. A new kernel config option CONFIG_OF_CONFIGFS is introduced and some additional sysfs attributes are added in case CONFIG_OF_OVERLAY is enabled. To make use of this feature, both CONFIG_OF_CONFIGFS and CONFIG_OF_OVERLAY need to be enabled in a targets kernel config. This is currently already the case for mediatek/mt7622 and mediatek/mt7623 as it has already been enabled by commit 401d7ebf2c ("mediatek: enable configfs for DT overlay on mt7622 and mt7623"). Signed-off-by: Daniel Golle <daniel@makrotopia.org> --- target/linux/generic/config-5.10 | 1 + .../hack-5.10/230-openwrt_lzma_options.patch | 2 +- ...-OF-DT-Overlay-configfs-interface-v7.patch | 395 ++++++++++++++++++ ...f-overlay-kobjectify-overlay-objects.patch | 157 +++++++ ...verlay-global-sysfs-enable-attribute.patch | 105 +++++ ...ation-ABI-overlays-global-attributes.patch | 40 ++ ...ocument-of_overlay_disable-parameter.patch | 23 + ...lay-add-per-overlay-sysfs-attributes.patch | 243 +++++++++++ ...tation-ABI-overlays-per-overlay-docs.patch | 46 ++ ...-of-rename-_node_sysfs-to-_node_post.patch | 150 +++++++ ...-symbols-when-CONFIG_OF_OVERLAY-is-u.patch | 27 ++ 11 files changed, 1188 insertions(+), 1 deletion(-) create mode 100644 target/linux/generic/pending-5.10/060-OF-DT-Overlay-configfs-interface-v7.patch create mode 100644 target/linux/generic/pending-5.10/061-of-overlay-kobjectify-overlay-objects.patch create mode 100644 target/linux/generic/pending-5.10/062-of-overlay-global-sysfs-enable-attribute.patch create mode 100644 target/linux/generic/pending-5.10/063-Documentation-ABI-overlays-global-attributes.patch create mode 100644 target/linux/generic/pending-5.10/064-Documentation-document-of_overlay_disable-parameter.patch create mode 100644 target/linux/generic/pending-5.10/065-of-overlay-add-per-overlay-sysfs-attributes.patch create mode 100644 target/linux/generic/pending-5.10/066-Documentation-ABI-overlays-per-overlay-docs.patch create mode 100644 target/linux/generic/pending-5.10/067-of-rename-_node_sysfs-to-_node_post.patch create mode 100644 target/linux/generic/pending-5.10/068-kbuild-Enable-DT-symbols-when-CONFIG_OF_OVERLAY-is-u.patch