| Message ID | 20230826090633.239342-2-sughosh.ganu@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Allow for removal of DT nodes and properties | expand |
On 8/26/23 11:06, Sughosh Ganu wrote: > Add a function which is registered to spy for a EVT_FT_FIXUP event, > and removes the non upstreamed nodes and properties from the > devicetree before it gets passed to the OS. > > This allows removing entire nodes, or specific properties under nodes > from the devicetree. The required nodes and properties can be > registered for removal through the DT_NON_COMPLIANT_PURGE and > DT_NON_COMPLIANT_PURGE_LIST macros. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > --- > include/dt-structs.h | 11 +++++++ > lib/Makefile | 1 + > lib/dt_purge.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 85 insertions(+) > create mode 100644 lib/dt_purge.c > > diff --git a/include/dt-structs.h b/include/dt-structs.h > index fa1622cb1d..f535c60471 100644 > --- a/include/dt-structs.h > +++ b/include/dt-structs.h > @@ -57,3 +57,14 @@ struct phandle_2_arg { > #endif > > #endif > + > +struct dt_non_compliant_purge { > + const char *node_path; > + const char *prop; > +}; > + > +#define DT_NON_COMPLIANT_PURGE(__name) \ > + ll_entry_declare(struct dt_non_compliant_purge, __name, dt_purge) > + > +#define DT_NON_COMPLIANT_PURGE_LIST(__name) \ > + ll_entry_declare_list(struct dt_non_compliant_purge, __name, dt_purge) > diff --git a/lib/Makefile b/lib/Makefile > index 8d8ccc8bbc..82a906daa0 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -37,6 +37,7 @@ endif > obj-y += crc8.o > obj-y += crc16.o > obj-y += crc16-ccitt.o > +obj-y += dt_purge.o > obj-$(CONFIG_ERRNO_STR) += errno_str.o > obj-$(CONFIG_FIT) += fdtdec_common.o > obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o > diff --git a/lib/dt_purge.c b/lib/dt_purge.c > new file mode 100644 > index 0000000000..f893ba9796 > --- /dev/null > +++ b/lib/dt_purge.c > @@ -0,0 +1,73 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2023, Linaro Limited > + */ > + > +#include <dt-structs.h> > +#include <event.h> > +#include <linker_lists.h> > + > +#include <linux/libfdt.h> > + > +/** > + * dt_non_compliant_purge() - Remove non-upstreamed nodes and properties > + * from the DT > + * @ctx: Context for event > + * @event: Event to process > + * > + * Iterate through an array of DT nodes and properties, and remove them > + * from the device-tree before the DT gets handed over to the kernel. > + * These are nodes and properties which do not have upstream bindings > + * and need to be purged before being handed over to the kernel. > + * > + * If both the node and property are specified, delete the property. If > + * only the node is specified, delete the entire node, including it's > + * subnodes, if any. > + * > + * Return: 0 if OK, -ve on error > + */ > +static int dt_non_compliant_purge(void *ctx, struct event *event) > +{ > + int nodeoff = 0; > + int err = 0; > + void *fdt; > + const struct event_ft_fixup *fixup = &event->data.ft_fixup; > + struct dt_non_compliant_purge *purge_entry; > + struct dt_non_compliant_purge *purge_start = > + ll_entry_start(struct dt_non_compliant_purge, dt_purge); > + int nentries = ll_entry_count(struct dt_non_compliant_purge, dt_purge); > + > + if (fixup->images) > + return 0; > + > + fdt = fixup->tree.fdt; > + for (purge_entry = purge_start; purge_entry != purge_start + nentries; > + purge_entry++) { > + nodeoff = fdt_path_offset(fdt, purge_entry->node_path); > + if (nodeoff < 0) { > + log_debug("Error (%d) getting node offset for %s\n", > + nodeoff, purge_entry->node_path); > + continue; > + } > + > + if (purge_entry->prop) { > + err = fdt_delprop(fdt, nodeoff, purge_entry->prop); > + if (err < 0 && err != -FDT_ERR_NOTFOUND) { > + log_debug("Error (%d) deleting %s\n", > + err, purge_entry->prop); > + goto out; > + } > + } else { > + err = fdt_del_node(fdt, nodeoff); > + if (err) { > + log_debug("Error (%d) trying to delete node %s\n", > + err, purge_entry->node_path); > + goto out; > + } > + } > + } > + > +out: > + return err; > +} > +EVENT_SPY(EVT_FT_FIXUP, dt_non_compliant_purge); This may interfere with other fixup code requiring U-Boot specific properties like bootmeth_vbe_ft_fixup(). We should ensure that call dt_non_compliant_purge() is the last fixup action. Please, consider a separate event. This code does not check if the property or node complies to the device tree scheme or not. So why not call the function dt_purge()? Best regards Heinrich
On 8/26/23 11:06, Sughosh Ganu wrote: > Add a function which is registered to spy for a EVT_FT_FIXUP event, > and removes the non upstreamed nodes and properties from the > devicetree before it gets passed to the OS. > > This allows removing entire nodes, or specific properties under nodes > from the devicetree. The required nodes and properties can be > registered for removal through the DT_NON_COMPLIANT_PURGE and > DT_NON_COMPLIANT_PURGE_LIST macros. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > --- > include/dt-structs.h | 11 +++++++ > lib/Makefile | 1 + > lib/dt_purge.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 85 insertions(+) > create mode 100644 lib/dt_purge.c > > diff --git a/include/dt-structs.h b/include/dt-structs.h > index fa1622cb1d..f535c60471 100644 > --- a/include/dt-structs.h > +++ b/include/dt-structs.h > @@ -57,3 +57,14 @@ struct phandle_2_arg { > #endif > > #endif > + > +struct dt_non_compliant_purge { > + const char *node_path; > + const char *prop; > +}; > + > +#define DT_NON_COMPLIANT_PURGE(__name) \ > + ll_entry_declare(struct dt_non_compliant_purge, __name, dt_purge) > + > +#define DT_NON_COMPLIANT_PURGE_LIST(__name) \ > + ll_entry_declare_list(struct dt_non_compliant_purge, __name, dt_purge) > diff --git a/lib/Makefile b/lib/Makefile > index 8d8ccc8bbc..82a906daa0 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -37,6 +37,7 @@ endif > obj-y += crc8.o > obj-y += crc16.o > obj-y += crc16-ccitt.o > +obj-y += dt_purge.o SPL can be the last boot stage (e.g. for Falcon Mode). So placing this under 'ifndef CONFIG_SPL_BUILD' is not correct. You need some logic that identifies into which boot stage this code belongs, e.g. use obj-$(CONFIG_$(SPL_TPL_)OF_LIBFDT). Best regards Heinrich > obj-$(CONFIG_ERRNO_STR) += errno_str.o > obj-$(CONFIG_FIT) += fdtdec_common.o > obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o > diff --git a/lib/dt_purge.c b/lib/dt_purge.c > new file mode 100644 > index 0000000000..f893ba9796 > --- /dev/null > +++ b/lib/dt_purge.c > @@ -0,0 +1,73 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2023, Linaro Limited > + */ > + > +#include <dt-structs.h> > +#include <event.h> > +#include <linker_lists.h> > + > +#include <linux/libfdt.h> > + > +/** > + * dt_non_compliant_purge() - Remove non-upstreamed nodes and properties > + * from the DT > + * @ctx: Context for event > + * @event: Event to process > + * > + * Iterate through an array of DT nodes and properties, and remove them > + * from the device-tree before the DT gets handed over to the kernel. > + * These are nodes and properties which do not have upstream bindings > + * and need to be purged before being handed over to the kernel. > + * > + * If both the node and property are specified, delete the property. If > + * only the node is specified, delete the entire node, including it's > + * subnodes, if any. > + * > + * Return: 0 if OK, -ve on error > + */ > +static int dt_non_compliant_purge(void *ctx, struct event *event) > +{ > + int nodeoff = 0; > + int err = 0; > + void *fdt; > + const struct event_ft_fixup *fixup = &event->data.ft_fixup; > + struct dt_non_compliant_purge *purge_entry; > + struct dt_non_compliant_purge *purge_start = > + ll_entry_start(struct dt_non_compliant_purge, dt_purge); > + int nentries = ll_entry_count(struct dt_non_compliant_purge, dt_purge); > + > + if (fixup->images) > + return 0; > + > + fdt = fixup->tree.fdt; > + for (purge_entry = purge_start; purge_entry != purge_start + nentries; > + purge_entry++) { > + nodeoff = fdt_path_offset(fdt, purge_entry->node_path); > + if (nodeoff < 0) { > + log_debug("Error (%d) getting node offset for %s\n", > + nodeoff, purge_entry->node_path); > + continue; > + } > + > + if (purge_entry->prop) { > + err = fdt_delprop(fdt, nodeoff, purge_entry->prop); > + if (err < 0 && err != -FDT_ERR_NOTFOUND) { > + log_debug("Error (%d) deleting %s\n", > + err, purge_entry->prop); > + goto out; > + } > + } else { > + err = fdt_del_node(fdt, nodeoff); > + if (err) { > + log_debug("Error (%d) trying to delete node %s\n", > + err, purge_entry->node_path); > + goto out; > + } > + } > + } > + > +out: > + return err; > +} > +EVENT_SPY(EVT_FT_FIXUP, dt_non_compliant_purge);
On Sat, 26 Aug 2023 at 15:51, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > > > > On 8/26/23 11:06, Sughosh Ganu wrote: > > Add a function which is registered to spy for a EVT_FT_FIXUP event, > > and removes the non upstreamed nodes and properties from the > > devicetree before it gets passed to the OS. > > > > This allows removing entire nodes, or specific properties under nodes > > from the devicetree. The required nodes and properties can be > > registered for removal through the DT_NON_COMPLIANT_PURGE and > > DT_NON_COMPLIANT_PURGE_LIST macros. > > > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > > --- > > include/dt-structs.h | 11 +++++++ > > lib/Makefile | 1 + > > lib/dt_purge.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 85 insertions(+) > > create mode 100644 lib/dt_purge.c > > > > diff --git a/include/dt-structs.h b/include/dt-structs.h > > index fa1622cb1d..f535c60471 100644 > > --- a/include/dt-structs.h > > +++ b/include/dt-structs.h > > @@ -57,3 +57,14 @@ struct phandle_2_arg { > > #endif > > > > #endif > > + > > +struct dt_non_compliant_purge { > > + const char *node_path; > > + const char *prop; > > +}; > > + > > +#define DT_NON_COMPLIANT_PURGE(__name) \ > > + ll_entry_declare(struct dt_non_compliant_purge, __name, dt_purge) > > + > > +#define DT_NON_COMPLIANT_PURGE_LIST(__name) \ > > + ll_entry_declare_list(struct dt_non_compliant_purge, __name, dt_purge) > > diff --git a/lib/Makefile b/lib/Makefile > > index 8d8ccc8bbc..82a906daa0 100644 > > --- a/lib/Makefile > > +++ b/lib/Makefile > > @@ -37,6 +37,7 @@ endif > > obj-y += crc8.o > > obj-y += crc16.o > > obj-y += crc16-ccitt.o > > +obj-y += dt_purge.o > > obj-$(CONFIG_ERRNO_STR) += errno_str.o > > obj-$(CONFIG_FIT) += fdtdec_common.o > > obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o > > diff --git a/lib/dt_purge.c b/lib/dt_purge.c > > new file mode 100644 > > index 0000000000..f893ba9796 > > --- /dev/null > > +++ b/lib/dt_purge.c > > @@ -0,0 +1,73 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > +/* > > + * Copyright (c) 2023, Linaro Limited > > + */ > > + > > +#include <dt-structs.h> > > +#include <event.h> > > +#include <linker_lists.h> > > + > > +#include <linux/libfdt.h> > > + > > +/** > > + * dt_non_compliant_purge() - Remove non-upstreamed nodes and properties > > + * from the DT > > + * @ctx: Context for event > > + * @event: Event to process > > + * > > + * Iterate through an array of DT nodes and properties, and remove them > > + * from the device-tree before the DT gets handed over to the kernel. > > + * These are nodes and properties which do not have upstream bindings > > + * and need to be purged before being handed over to the kernel. > > + * > > + * If both the node and property are specified, delete the property. If > > + * only the node is specified, delete the entire node, including it's > > + * subnodes, if any. > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +static int dt_non_compliant_purge(void *ctx, struct event *event) > > +{ > > + int nodeoff = 0; > > + int err = 0; > > + void *fdt; > > + const struct event_ft_fixup *fixup = &event->data.ft_fixup; > > + struct dt_non_compliant_purge *purge_entry; > > + struct dt_non_compliant_purge *purge_start = > > + ll_entry_start(struct dt_non_compliant_purge, dt_purge); > > + int nentries = ll_entry_count(struct dt_non_compliant_purge, dt_purge); > > + > > + if (fixup->images) > > + return 0; > > + > > + fdt = fixup->tree.fdt; > > + for (purge_entry = purge_start; purge_entry != purge_start + nentries; > > + purge_entry++) { > > + nodeoff = fdt_path_offset(fdt, purge_entry->node_path); > > + if (nodeoff < 0) { > > + log_debug("Error (%d) getting node offset for %s\n", > > + nodeoff, purge_entry->node_path); > > + continue; > > + } > > + > > + if (purge_entry->prop) { > > + err = fdt_delprop(fdt, nodeoff, purge_entry->prop); > > + if (err < 0 && err != -FDT_ERR_NOTFOUND) { > > + log_debug("Error (%d) deleting %s\n", > > + err, purge_entry->prop); > > + goto out; > > + } > > + } else { > > + err = fdt_del_node(fdt, nodeoff); > > + if (err) { > > + log_debug("Error (%d) trying to delete node %s\n", > > + err, purge_entry->node_path); > > + goto out; > > + } > > + } > > + } > > + > > +out: > > + return err; > > +} > > +EVENT_SPY(EVT_FT_FIXUP, dt_non_compliant_purge); > > This may interfere with other fixup code requiring U-Boot specific > properties like bootmeth_vbe_ft_fixup(). Okay, I was thinking if we can have a flag to indicate which event handler is to be run. I will check this, and add a separate event if this solution turns to be overly complex. > > We should ensure that call dt_non_compliant_purge() is the last fixup > action. Please, consider a separate event. Will check. > > This code does not check if the property or node complies to the device > tree scheme or not. So why not call the function dt_purge()? Okay -sughosh
On Sat, 26 Aug 2023 at 16:09, Heinrich Schuchardt <xypron.glpk@gmx.de> wrote: > > On 8/26/23 11:06, Sughosh Ganu wrote: > > Add a function which is registered to spy for a EVT_FT_FIXUP event, > > and removes the non upstreamed nodes and properties from the > > devicetree before it gets passed to the OS. > > > > This allows removing entire nodes, or specific properties under nodes > > from the devicetree. The required nodes and properties can be > > registered for removal through the DT_NON_COMPLIANT_PURGE and > > DT_NON_COMPLIANT_PURGE_LIST macros. > > > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > > --- > > include/dt-structs.h | 11 +++++++ > > lib/Makefile | 1 + > > lib/dt_purge.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 85 insertions(+) > > create mode 100644 lib/dt_purge.c > > > > diff --git a/include/dt-structs.h b/include/dt-structs.h > > index fa1622cb1d..f535c60471 100644 > > --- a/include/dt-structs.h > > +++ b/include/dt-structs.h > > @@ -57,3 +57,14 @@ struct phandle_2_arg { > > #endif > > > > #endif > > + > > +struct dt_non_compliant_purge { > > + const char *node_path; > > + const char *prop; > > +}; > > + > > +#define DT_NON_COMPLIANT_PURGE(__name) \ > > + ll_entry_declare(struct dt_non_compliant_purge, __name, dt_purge) > > + > > +#define DT_NON_COMPLIANT_PURGE_LIST(__name) \ > > + ll_entry_declare_list(struct dt_non_compliant_purge, __name, dt_purge) > > diff --git a/lib/Makefile b/lib/Makefile > > index 8d8ccc8bbc..82a906daa0 100644 > > --- a/lib/Makefile > > +++ b/lib/Makefile > > @@ -37,6 +37,7 @@ endif > > obj-y += crc8.o > > obj-y += crc16.o > > obj-y += crc16-ccitt.o > > +obj-y += dt_purge.o > > SPL can be the last boot stage (e.g. for Falcon Mode). So placing this > under 'ifndef CONFIG_SPL_BUILD' is not correct. > > You need some logic that identifies into which boot stage this code > belongs, e.g. use obj-$(CONFIG_$(SPL_TPL_)OF_LIBFDT). Okay. Will check and add this under the suggested config symbol. -sughosh > > Best regards > > Heinrich > > > obj-$(CONFIG_ERRNO_STR) += errno_str.o > > obj-$(CONFIG_FIT) += fdtdec_common.o > > obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o > > diff --git a/lib/dt_purge.c b/lib/dt_purge.c > > new file mode 100644 > > index 0000000000..f893ba9796 > > --- /dev/null > > +++ b/lib/dt_purge.c > > @@ -0,0 +1,73 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > +/* > > + * Copyright (c) 2023, Linaro Limited > > + */ > > + > > +#include <dt-structs.h> > > +#include <event.h> > > +#include <linker_lists.h> > > + > > +#include <linux/libfdt.h> > > + > > +/** > > + * dt_non_compliant_purge() - Remove non-upstreamed nodes and properties > > + * from the DT > > + * @ctx: Context for event > > + * @event: Event to process > > + * > > + * Iterate through an array of DT nodes and properties, and remove them > > + * from the device-tree before the DT gets handed over to the kernel. > > + * These are nodes and properties which do not have upstream bindings > > + * and need to be purged before being handed over to the kernel. > > + * > > + * If both the node and property are specified, delete the property. If > > + * only the node is specified, delete the entire node, including it's > > + * subnodes, if any. > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +static int dt_non_compliant_purge(void *ctx, struct event *event) > > +{ > > + int nodeoff = 0; > > + int err = 0; > > + void *fdt; > > + const struct event_ft_fixup *fixup = &event->data.ft_fixup; > > + struct dt_non_compliant_purge *purge_entry; > > + struct dt_non_compliant_purge *purge_start = > > + ll_entry_start(struct dt_non_compliant_purge, dt_purge); > > + int nentries = ll_entry_count(struct dt_non_compliant_purge, dt_purge); > > + > > + if (fixup->images) > > + return 0; > > + > > + fdt = fixup->tree.fdt; > > + for (purge_entry = purge_start; purge_entry != purge_start + nentries; > > + purge_entry++) { > > + nodeoff = fdt_path_offset(fdt, purge_entry->node_path); > > + if (nodeoff < 0) { > > + log_debug("Error (%d) getting node offset for %s\n", > > + nodeoff, purge_entry->node_path); > > + continue; > > + } > > + > > + if (purge_entry->prop) { > > + err = fdt_delprop(fdt, nodeoff, purge_entry->prop); > > + if (err < 0 && err != -FDT_ERR_NOTFOUND) { > > + log_debug("Error (%d) deleting %s\n", > > + err, purge_entry->prop); > > + goto out; > > + } > > + } else { > > + err = fdt_del_node(fdt, nodeoff); > > + if (err) { > > + log_debug("Error (%d) trying to delete node %s\n", > > + err, purge_entry->node_path); > > + goto out; > > + } > > + } > > + } > > + > > +out: > > + return err; > > +} > > +EVENT_SPY(EVT_FT_FIXUP, dt_non_compliant_purge); >
On Sat, Aug 26, 2023 at 02:36:29PM +0530, Sughosh Ganu wrote: > Add a function which is registered to spy for a EVT_FT_FIXUP event, > and removes the non upstreamed nodes and properties from the > devicetree before it gets passed to the OS. > > This allows removing entire nodes, or specific properties under nodes > from the devicetree. The required nodes and properties can be > registered for removal through the DT_NON_COMPLIANT_PURGE and > DT_NON_COMPLIANT_PURGE_LIST macros. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> So, the conceptual problem here is that while we do need to have a way to purge nodes and properties that have been rejected by upstream, we also need to ensure an upstream attempt was made. To that end, how I envision things is: - When we build the docs, something under doc/develop/ has a page / section for each binding we're purging, which links to and summarizes why it's not appropriate for upstream. - It's non-default to purge said nodes. - We at least make checkpatch / et al complain about new purges being added, and CI failing on the number of purges increasing without also increasing the number of allowed purges.
diff --git a/include/dt-structs.h b/include/dt-structs.h index fa1622cb1d..f535c60471 100644 --- a/include/dt-structs.h +++ b/include/dt-structs.h @@ -57,3 +57,14 @@ struct phandle_2_arg { #endif #endif + +struct dt_non_compliant_purge { + const char *node_path; + const char *prop; +}; + +#define DT_NON_COMPLIANT_PURGE(__name) \ + ll_entry_declare(struct dt_non_compliant_purge, __name, dt_purge) + +#define DT_NON_COMPLIANT_PURGE_LIST(__name) \ + ll_entry_declare_list(struct dt_non_compliant_purge, __name, dt_purge) diff --git a/lib/Makefile b/lib/Makefile index 8d8ccc8bbc..82a906daa0 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -37,6 +37,7 @@ endif obj-y += crc8.o obj-y += crc16.o obj-y += crc16-ccitt.o +obj-y += dt_purge.o obj-$(CONFIG_ERRNO_STR) += errno_str.o obj-$(CONFIG_FIT) += fdtdec_common.o obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o diff --git a/lib/dt_purge.c b/lib/dt_purge.c new file mode 100644 index 0000000000..f893ba9796 --- /dev/null +++ b/lib/dt_purge.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2023, Linaro Limited + */ + +#include <dt-structs.h> +#include <event.h> +#include <linker_lists.h> + +#include <linux/libfdt.h> + +/** + * dt_non_compliant_purge() - Remove non-upstreamed nodes and properties + * from the DT + * @ctx: Context for event + * @event: Event to process + * + * Iterate through an array of DT nodes and properties, and remove them + * from the device-tree before the DT gets handed over to the kernel. + * These are nodes and properties which do not have upstream bindings + * and need to be purged before being handed over to the kernel. + * + * If both the node and property are specified, delete the property. If + * only the node is specified, delete the entire node, including it's + * subnodes, if any. + * + * Return: 0 if OK, -ve on error + */ +static int dt_non_compliant_purge(void *ctx, struct event *event) +{ + int nodeoff = 0; + int err = 0; + void *fdt; + const struct event_ft_fixup *fixup = &event->data.ft_fixup; + struct dt_non_compliant_purge *purge_entry; + struct dt_non_compliant_purge *purge_start = + ll_entry_start(struct dt_non_compliant_purge, dt_purge); + int nentries = ll_entry_count(struct dt_non_compliant_purge, dt_purge); + + if (fixup->images) + return 0; + + fdt = fixup->tree.fdt; + for (purge_entry = purge_start; purge_entry != purge_start + nentries; + purge_entry++) { + nodeoff = fdt_path_offset(fdt, purge_entry->node_path); + if (nodeoff < 0) { + log_debug("Error (%d) getting node offset for %s\n", + nodeoff, purge_entry->node_path); + continue; + } + + if (purge_entry->prop) { + err = fdt_delprop(fdt, nodeoff, purge_entry->prop); + if (err < 0 && err != -FDT_ERR_NOTFOUND) { + log_debug("Error (%d) deleting %s\n", + err, purge_entry->prop); + goto out; + } + } else { + err = fdt_del_node(fdt, nodeoff); + if (err) { + log_debug("Error (%d) trying to delete node %s\n", + err, purge_entry->node_path); + goto out; + } + } + } + +out: + return err; +} +EVENT_SPY(EVT_FT_FIXUP, dt_non_compliant_purge);
Add a function which is registered to spy for a EVT_FT_FIXUP event, and removes the non upstreamed nodes and properties from the devicetree before it gets passed to the OS. This allows removing entire nodes, or specific properties under nodes from the devicetree. The required nodes and properties can be registered for removal through the DT_NON_COMPLIANT_PURGE and DT_NON_COMPLIANT_PURGE_LIST macros. Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> --- include/dt-structs.h | 11 +++++++ lib/Makefile | 1 + lib/dt_purge.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 85 insertions(+) create mode 100644 lib/dt_purge.c