On Thu, Nov 18, 2021 at 04:26:29PM +1100, David Gibson wrote:
> On Wed, Nov 17, 2021 at 06:53:56PM -0800, Vikram Garhwal wrote:
> > This is done to get the target path for the overlay nodes which is very useful
> > in many cases. For example, Xen hypervisor needs it when applying overlays
> > because Xen needs to do further processing of the overlay nodes, e.g. mapping of
> > resources(IRQs and IOMMUs) to other VMs, creation of SMMU pagetables, etc.
> >
> > Signed-off-by: Vikram Garhwal <fnu.vikram@xxxxxxxxxx>
>
> Applied, thanks.
Thanks!
>
> If you can follow up with some testcases for the newly-public
> function, that would be most appreciated.
Sure, will check the existing test cases and add tests for new public function.
Regards,
Vikram
>
> > ---
> > libfdt/fdt_overlay.c | 29 +++++++----------------------
> > libfdt/libfdt.h | 18 ++++++++++++++++++
> > libfdt/version.lds | 1 +
> > 3 files changed, 26 insertions(+), 22 deletions(-)
> >
> > diff --git a/libfdt/fdt_overlay.c b/libfdt/fdt_overlay.c
> > index d217e79..5c0c398 100644
> > --- a/libfdt/fdt_overlay.c
> > +++ b/libfdt/fdt_overlay.c
> > @@ -40,37 +40,22 @@ static uint32_t overlay_get_target_phandle(const void *fdto, int fragment)
> > return fdt32_to_cpu(*val);
> > }
> >
> > -/**
> > - * overlay_get_target - retrieves the offset of a fragment's target
> > - * @fdt: Base device tree blob
> > - * @fdto: Device tree overlay blob
> > - * @fragment: node offset of the fragment in the overlay
> > - * @pathp: pointer which receives the path of the target (or NULL)
> > - *
> > - * overlay_get_target() retrieves the target offset in the base
> > - * device tree of a fragment, no matter how the actual targeting is
> > - * done (through a phandle or a path)
> > - *
> > - * returns:
> > - * the targeted node offset in the base device tree
> > - * Negative error code on error
> > - */
> > -static int overlay_get_target(const void *fdt, const void *fdto,
> > - int fragment, char const **pathp)
> > +int fdt_overlay_target_offset(const void *fdt, const void *fdto,
> > + int fragment_offset, char const **pathp)
> > {
> > uint32_t phandle;
> > const char *path = NULL;
> > int path_len = 0, ret;
> >
> > /* Try first to do a phandle based lookup */
> > - phandle = overlay_get_target_phandle(fdto, fragment);
> > + phandle = overlay_get_target_phandle(fdto, fragment_offset);
> > if (phandle == (uint32_t)-1)
> > return -FDT_ERR_BADPHANDLE;
> >
> > /* no phandle, try path */
> > if (!phandle) {
> > /* And then a path based lookup */
> > - path = fdt_getprop(fdto, fragment, "target-path", &path_len);
> > + path = fdt_getprop(fdto, fragment_offset, "target-path", &path_len);
> > if (path)
> > ret = fdt_path_offset(fdt, path);
> > else
> > @@ -636,7 +621,7 @@ static int overlay_merge(void *fdt, void *fdto)
> > if (overlay < 0)
> > return overlay;
> >
> > - target = overlay_get_target(fdt, fdto, fragment, NULL);
> > + target = fdt_overlay_target_offset(fdt, fdto, fragment, NULL);
> > if (target < 0)
> > return target;
> >
> > @@ -779,7 +764,7 @@ static int overlay_symbol_update(void *fdt, void *fdto)
> > return -FDT_ERR_BADOVERLAY;
> >
> > /* get the target of the fragment */
> > - ret = overlay_get_target(fdt, fdto, fragment, &target_path);
> > + ret = fdt_overlay_target_offset(fdt, fdto, fragment, &target_path);
> > if (ret < 0)
> > return ret;
> > target = ret;
> > @@ -801,7 +786,7 @@ static int overlay_symbol_update(void *fdt, void *fdto)
> >
> > if (!target_path) {
> > /* again in case setprop_placeholder changed it */
> > - ret = overlay_get_target(fdt, fdto, fragment, &target_path);
> > + ret = fdt_overlay_target_offset(fdt, fdto, fragment, &target_path);
> > if (ret < 0)
> > return ret;
> > target = ret;
> > diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
> > index 7f117e8..a7f432c 100644
> > --- a/libfdt/libfdt.h
> > +++ b/libfdt/libfdt.h
> > @@ -2116,6 +2116,24 @@ int fdt_del_node(void *fdt, int nodeoffset);
> > */
> > int fdt_overlay_apply(void *fdt, void *fdto);
> >
> > +/**
> > + * fdt_overlay_target_offset - retrieves the offset of a fragment's target
> > + * @fdt: Base device tree blob
> > + * @fdto: Device tree overlay blob
> > + * @fragment_offset: node offset of the fragment in the overlay
> > + * @pathp: pointer which receives the path of the target (or NULL)
> > + *
> > + * fdt_overlay_target_offset() retrieves the target offset in the base
> > + * device tree of a fragment, no matter how the actual targeting is
> > + * done (through a phandle or a path)
> > + *
> > + * returns:
> > + * the targeted node offset in the base device tree
> > + * Negative error code on error
> > + */
> > +int fdt_overlay_target_offset(const void *fdt, const void *fdto,
> > + int fragment_offset, char const **pathp);
> > +
> > /**********************************************************************/
> > /* Debugging / informational functions */
> > /**********************************************************************/
> > diff --git a/libfdt/version.lds b/libfdt/version.lds
> > index 7ab85f1..cbce5d4 100644
> > --- a/libfdt/version.lds
> > +++ b/libfdt/version.lds
> > @@ -77,6 +77,7 @@ LIBFDT_1.2 {
> > fdt_appendprop_addrrange;
> > fdt_setprop_inplace_namelen_partial;
> > fdt_create_with_flags;
> > + fdt_overlay_target_offset;
> > local:
> > *;
> > };
>
> --
> David Gibson | I'll have my music baroque, and my code
> david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
> | _way_ _around_!
> http://www.ozlabs.org/~dgibson
