[U-Boot] [PATCH 00/32] Initial sparse fix series

Jerry Van Baren
2012-10-18T00:19:23Z

Hi David, Jon,

Kim Phillips created a series of patches to change variable declarations
that are big endian to be __be32/__be64. Since the device tree is
defined to be big endian, he created a patch to mark the appropriate
libfdt entities as __be*.

On 10/16/2012 08:28 PM, Kim Phillips wrote:
> This 32-patch series only begins to address making u-boot source more
> 'sparseable,' or sparse-clean, ultimately to catch type, address space,
> and endianness mismatches and generally improve code quality. E.g., in this
> initial dose whose main purpose is to reduce the output volume to workable
> levels, a couple of endianness bugs are found and fixed in
> of_bus_default_translate() and fdt_get_base_address(). See [PATCH 14/32]
> common/fdt_support.c: sparse fixes.

Upside: This is very good for identifying endian errors early.
Downside: It could break/complicate non-linux uses of libfdt.

What are your thoughts on this quest?

[snip]

> Note that there are two libfdt dependencies:

[snipped #1, u-boot-fdt dependency, NBD]

> 2. potential upstream dtc change dependencies, due to having to attribute base
> device tree header types to __be32 in include/libfdt. See patch 19/32
> "include/fdt.h: sparse fixes". It is unknown whether such changes would
> be welcome to dtc (but there's a way to find out :).

[snip]

> Build-tested in both endians :). Please help test.
>
> Thanks,
>
> Kim

Below is the actual patch for reference (it was in a separate email).
The impact in terms of changed lines is pretty small. I'm not sure how
this impacts non-linux / non-gcc systems since the sparse checker comes
from a linux background and uses gcc extensions.

Possibly this could be handled a definition:

#ifndef _LINUX_TYPES_H
typedef uint32_t __be32
typedef uint64_t __be64
#endif

> include/fdt.h | 33 +++++++++++++++++----------------
> include/fdt_support.h | 2 ++
> include/libfdt.h | 4 ++--
> lib/libfdt/fdt.c | 2 +-
> lib/libfdt/fdt_ro.c | 2 +-
> lib/libfdt/fdt_rw.c | 4 ++--
> lib/libfdt/fdt_sw.c | 4 ++--
> lib/libfdt/fdt_wip.c | 2 +-
> 8 files changed, 28 insertions(+), 25 deletions(-)
>
> diff --git a/include/fdt.h b/include/fdt.h
> index c51212e..1b7f044 100644
> --- a/include/fdt.h
> +++ b/include/fdt.h
> @@ -2,40 +2,41 @@
> #define _FDT_H
>
> #ifndef __ASSEMBLY__
> +#include <asm/byteorder.h>
>
> struct fdt_header {
> - uint32_t magic; /* magic word FDT_MAGIC */
> - uint32_t totalsize; /* total size of DT block */
> - uint32_t off_dt_struct; /* offset to structure */
> - uint32_t off_dt_strings; /* offset to strings */
> - uint32_t off_mem_rsvmap; /* offset to memory reserve map */
> - uint32_t version; /* format version */
> - uint32_t last_comp_version; /* last compatible version */
> + __be32 magic; /* magic word FDT_MAGIC */
> + __be32 totalsize; /* total size of DT block */
> + __be32 off_dt_struct; /* offset to structure */
> + __be32 off_dt_strings; /* offset to strings */
> + __be32 off_mem_rsvmap; /* offset to memory reserve map */
> + __be32 version; /* format version */
> + __be32 last_comp_version; /* last compatible version */
>
> /* version 2 fields below */
> - uint32_t boot_cpuid_phys; /* Which physical CPU id we're
> + __be32 boot_cpuid_phys; /* Which physical CPU id we're
> booting on */
> /* version 3 fields below */
> - uint32_t size_dt_strings; /* size of the strings block */
> + __be32 size_dt_strings; /* size of the strings block */
>
> /* version 17 fields below */
> - uint32_t size_dt_struct; /* size of the structure block */
> + __be32 size_dt_struct; /* size of the structure block */
> };
>
> struct fdt_reserve_entry {
> - uint64_t address;
> - uint64_t size;
> + __be64 address;
> + __be64 size;
> };
>
> struct fdt_node_header {
> - uint32_t tag;
> + __be32 tag;
> char name[0];
> };
>
> struct fdt_property {
> - uint32_t tag;
> - uint32_t len;
> - uint32_t nameoff;
> + __be32 tag;
> + __be32 len;
> + __be32 nameoff;
> char data[0];
> };
>
> diff --git a/include/fdt_support.h b/include/fdt_support.h
> index 2e18d82..399b73f 100644
> --- a/include/fdt_support.h
> +++ b/include/fdt_support.h
> @@ -81,7 +81,9 @@ int fdt_pci_dma_ranges(void *blob, int phb_off, struct pci_controller *hose);
> #ifdef CONFIG_OF_BOARD_SETUP
> void ft_board_setup(void *blob, bd_t *bd);
> void ft_cpu_setup(void *blob, bd_t *bd);
> +void ft_fixup_num_cores(void *blob);
> void ft_pci_setup(void *blob, bd_t *bd);
> +void ft_srio_setup(void *blob);
> #endif
>
> void set_working_fdt_addr(void *addr);
> diff --git a/include/libfdt.h b/include/libfdt.h
> index 4589c5f..ab98d23 100644
> --- a/include/libfdt.h
> +++ b/include/libfdt.h
> @@ -1153,8 +1153,8 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name,
> static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
> uint32_t val)
> {
> - val = cpu_to_fdt32(val);
> - return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
> + __be32 tmp = cpu_to_fdt32(val);
> + return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
> }
>
> /**
> diff --git a/lib/libfdt/fdt.c b/lib/libfdt/fdt.c
> index 4157b21..5a82c60 100644
> --- a/lib/libfdt/fdt.c
> +++ b/lib/libfdt/fdt.c
> @@ -96,7 +96,7 @@ const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
>
> uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
> {
> - const uint32_t *tagp, *lenp;
> + const __be32 *tagp, *lenp;
> uint32_t tag;
> int offset = startoffset;
> const char *p;
> diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c
> index 1933010..4e3d87a 100644
> --- a/lib/libfdt/fdt_ro.c
> +++ b/lib/libfdt/fdt_ro.c
> @@ -326,7 +326,7 @@ const void *fdt_getprop(const void *fdt, int nodeoffset,
>
> uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
> {
> - const uint32_t *php;
> + const __be32 *php;
> int len;
>
> /* FIXME: This is a bit sub-optimal, since we potentially scan
> diff --git a/lib/libfdt/fdt_rw.c b/lib/libfdt/fdt_rw.c
> index 5ed23d6..688b817 100644
> --- a/lib/libfdt/fdt_rw.c
> +++ b/lib/libfdt/fdt_rw.c
> @@ -343,7 +343,7 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
> int nodelen;
> int err;
> uint32_t tag;
> - uint32_t *endtag;
> + __be32 *endtag;
>
> FDT_RW_CHECK_HEADER(fdt);
>
> @@ -370,7 +370,7 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
> nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
> memset(nh->name, 0, FDT_TAGALIGN(namelen+1));
> memcpy(nh->name, name, namelen);
> - endtag = (uint32_t *)((char *)nh + nodelen - FDT_TAGSIZE);
> + endtag = (__be32 *)((char *)nh + nodelen - FDT_TAGSIZE);
> *endtag = cpu_to_fdt32(FDT_END_NODE);
>
> return offset;
> diff --git a/lib/libfdt/fdt_sw.c b/lib/libfdt/fdt_sw.c
> index 55ebebf..5ce91ba 100644
> --- a/lib/libfdt/fdt_sw.c
> +++ b/lib/libfdt/fdt_sw.c
> @@ -153,7 +153,7 @@ int fdt_begin_node(void *fdt, const char *name)
>
> int fdt_end_node(void *fdt)
> {
> - uint32_t *en;
> + __be32 *en;
>
> FDT_SW_CHECK_HEADER(fdt);
>
> @@ -213,7 +213,7 @@ int fdt_property(void *fdt, const char *name, const void *val, int len)
> int fdt_finish(void *fdt)
> {
> char *p = (char *)fdt;
> - uint32_t *end;
> + __be32 *end;
> int oldstroffset, newstroffset;
> uint32_t tag;
> int offset, nextoffset;
> diff --git a/lib/libfdt/fdt_wip.c b/lib/libfdt/fdt_wip.c
> index e373677..dc1e14c 100644
> --- a/lib/libfdt/fdt_wip.c
> +++ b/lib/libfdt/fdt_wip.c
> @@ -78,7 +78,7 @@ int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
>
> static void _fdt_nop_region(void *start, int len)
> {
> - uint32_t *p;
> + __be32 *p;
>
> for (p = start; (char *)p < ((char *)start + len); p++)
> *p = cpu_to_fdt32(FDT_NOP);