> -----Original Message----- > From: Grant Likely [mailto:glikely@xxxxxxxxxxxx] On Behalf Of Grant Likely > Sent: Wednesday, September 24, 2014 10:45 PM > To: Wang, Yalin; 'robh+dt@xxxxxxxxxx'; 'devicetree@xxxxxxxxxxxxxxx'; > 'pawel.moll@xxxxxxx'; 'mark.rutland@xxxxxxx'; > 'ijc+devicetree@xxxxxxxxxxxxxx'; 'linux-kernel@xxxxxxxxxxxxxxx' > Subject: Re: [RFC] fdt:free the fdt reserved memory > > On Thu, 18 Sep 2014 17:25:12 +0800, "Wang, Yalin" > <Yalin.Wang@xxxxxxxxxxxxxx> wrote: > > This patch make some change to unflatten_dt_node(), make sure the > > device_node don't reference to fdt raw blob memory, so that we can > > free the raw blob reserved memory after initcalls. > > > > Signed-off-by: Yalin Wang <yalin.wang@xxxxxxxxxxxxxx> > > Do you have any measurements showing a change in available memory before > and after the patch? > Does anyone have a look at this patch? It can save 12K on my platform, My dtb is 164K Thanks > > > --- > > drivers/of/fdt.c | 27 +++++++++++++++++++++++---- > > include/linux/of_fdt.h | 2 ++ > > 2 files changed, 25 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index > > 79cb831..e891ef6 100644 > > --- a/drivers/of/fdt.c > > +++ b/drivers/of/fdt.c > > @@ -240,6 +240,7 @@ static void * unflatten_dt_node(void *blob, > > (offset = fdt_next_property_offset(blob, offset))) { > > const char *pname; > > u32 sz; > > + int name_len; > > > > if (!(p = fdt_getprop_by_offset(blob, offset, &pname, &sz))) { > > offset = -FDT_ERR_INTERNAL; > > @@ -250,10 +251,12 @@ static void * unflatten_dt_node(void *blob, > > pr_info("Can't find property name in list !\n"); > > break; > > } > > + name_len = strlen(pname); > > if (strcmp(pname, "name") == 0) > > has_name = 1; > > - pp = unflatten_dt_alloc(&mem, sizeof(struct property), > > - __alignof__(struct property)); > > + pp = unflatten_dt_alloc(&mem, > > + ALIGN(sizeof(struct property) + name_len + 1, 4) > > + + sz, __alignof__(struct property)); > > if (allnextpp) { > > /* We accept flattened tree phandles either in > > * ePAPR-style "phandle" properties, or the @@ -270,9 > +273,11 @@ > > static void * unflatten_dt_node(void *blob, > > * stuff */ > > if (strcmp(pname, "ibm,phandle") == 0) > > np->phandle = be32_to_cpup(p); > > - pp->name = (char *)pname; > > + pp->name = (char *)memcpy(pp + 1, pname, name_len + 1); > > pp->length = sz; > > - pp->value = (__be32 *)p; > > + pp->value = (__be32 *)memcpy((void *)pp + > > + ALIGN(sizeof(struct property) + > > + name_len + 1, 4), p, sz); > > *prev_pp = pp; > > prev_pp = &pp->next; > > } > > @@ -564,6 +569,20 @@ void __init early_init_fdt_scan_reserved_mem(void) > > fdt_init_reserved_mem(); > > } > > > > +void __init free_early_init_fdt_scan_reserved_mem(void) > > +{ > > + unsigned long start, end, size; > > + if (!initial_boot_params) > > + return; > > + > > + size = fdt_totalsize(initial_boot_params); > > + memblock_free(__pa(initial_boot_params), size); > > + start = round_down((unsigned long)initial_boot_params, PAGE_SIZE); > > + end = round_up((unsigned long)initial_boot_params + size, PAGE_SIZE); > > + free_reserved_area((void *)start, (void *)end, 0, "fdt"); > > + initial_boot_params = 0; > > +} > > + > > /** > > * of_scan_flat_dt - scan flattened tree blob and call callback on each. > > * @it: callback function > > diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h index > > 0ff360d..21d51ce 100644 > > --- a/include/linux/of_fdt.h > > +++ b/include/linux/of_fdt.h > > @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long > > node, const char *uname, extern int early_init_dt_scan_memory(unsigned > long node, const char *uname, > > int depth, void *data); > > extern void early_init_fdt_scan_reserved_mem(void); > > +extern void free_early_init_fdt_scan_reserved_mem(void); > > extern void early_init_dt_add_memory_arch(u64 base, u64 size); > > extern int early_init_dt_reserve_memory_arch(phys_addr_t base, > phys_addr_t size, > > bool no_map); > > @@ -89,6 +90,7 @@ extern u64 fdt_translate_address(const void *blob, > > int node_offset); extern void of_fdt_limit_memory(int limit); #else > > /* CONFIG_OF_FLATTREE */ static inline void > > early_init_fdt_scan_reserved_mem(void) {} > > +static inline void free_early_init_fdt_scan_reserved_mem(void) {} > > static inline const char *of_flat_dt_get_machine_name(void) { return > > NULL; } static inline void unflatten_device_tree(void) {} static > > inline void unflatten_and_copy_device_tree(void) {} > > -- > > 2.1.0 > > -- > > To unsubscribe from this list: send the line "unsubscribe > > linux-kernel" in the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
