[RFC PATCH 04/10] FWU: Add metadata access functions for GPT partitioned block devices

[Sughosh Ganu]

On Thu, 9 Dec 2021 at 15:06, Jason Liu <jason.hui.liu at nxp.com> wrote:

>
>
> > -----Original Message-----
> > From: Sughosh Ganu <sughosh.ganu at linaro.org>
> > Sent: 2021年11月25日 15:02
> > To: u-boot at lists.denx.de
> > Cc: Patrick Delaunay <patrick.delaunay at foss.st.com>; Patrice Chotard
> > <patrice.chotard at foss.st.com>; Heinrich Schuchardt <xypron.glpk at gmx.de>;
> > Alexander Graf <agraf at csgraf.de>; Simon Glass <sjg at chromium.org>; Bin
> > Meng <bmeng.cn at gmail.com>; Peng Fan <peng.fan at nxp.com>; AKASHI
> > Takahiro <takahiro.akashi at linaro.org>; Ilias Apalodimas
> > <ilias.apalodimas at linaro.org>; Jose Marinho <jose.marinho at arm.com>;
> Grant
> > Likely <grant.likely at arm.com>; Jason Liu <jason.hui.liu at nxp.com>;
> Sughosh
> > Ganu <sughosh.ganu at linaro.org>
> > Subject: [RFC PATCH 04/10] FWU: Add metadata access functions for GPT
> > partitioned block devices
> >
> > In the FWU Multi Bank Update feature, the information about the updatable
> > images is stored as part of the metadata, on a separate partition. Add
> > functions for reading from and writing to the metadata when the updatable
> > images and the metadata are stored on a block device which is formated
> with
> > GPT based partition scheme.
> >
> > Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
> > ---
> >  lib/fwu_updates/fwu_metadata_gpt_blk.c | 716
> > +++++++++++++++++++++++++
> >  1 file changed, 716 insertions(+)
> >  create mode 100644 lib/fwu_updates/fwu_metadata_gpt_blk.c
> >
> > diff --git a/lib/fwu_updates/fwu_metadata_gpt_blk.c
> > b/lib/fwu_updates/fwu_metadata_gpt_blk.c
> > new file mode 100644
> > index 0000000000..98cc53f706
> > --- /dev/null
> > +++ b/lib/fwu_updates/fwu_metadata_gpt_blk.c
> > @@ -0,0 +1,716 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (c) 2021, Linaro Limited
> > + */
> > +
> > +#include <blk.h>
> > +#include <efi_loader.h>
> > +#include <fwu_metadata.h>
> > +#include <malloc.h>
> > +#include <memalign.h>
> > +#include <part.h>
> > +#include <part_efi.h>
> > +
> > +#include <linux/errno.h>
> > +#include <linux/types.h>
> > +#include <u-boot/crc.h>
> > +
> > +#define PRIMARY_VALID                0x1
> > +#define SECONDARY_VALID              0x2
> > +
> > +#define MDATA_READ           (u8)0x1
> > +#define MDATA_WRITE          (u8)0x2
> > +
> > +#define IMAGE_ACCEPT_SET     (u8)0x1
> > +#define IMAGE_ACCEPT_CLEAR   (u8)0x2
>
> Better to define as the followings:
>
> #define MDATA_READ              ((u8)0x1)
> #define MDATA_WRITE             ((u8)0x2)
>
> #define IMAGE_ACCEPT_SET        ((u8)0x1)
> #define IMAGE_ACCEPT_CLEAR      ((u8)0x2)
>

Ilias had suggested using the BIT macros for this. I have made that change.
Hope that is fine.


>
> > +
> > +static int gpt_verify_metadata(struct fwu_metadata *metadata, bool
> > +pri_part) {
> > +     u32 calc_crc32;
> > +     void *buf;
> > +
> > +     buf = &metadata->version;
> > +     calc_crc32 = crc32(0, buf, sizeof(*metadata) - sizeof(u32));
> > +
> > +     if (calc_crc32 != metadata->crc32) {
> > +             log_err("crc32 check failed for %s metadata partition\n",
> > +                     pri_part ? "primary" : "secondary");
> > +             return -1;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int gpt_get_metadata_partitions(struct blk_desc *desc,
> > +                                    u32 *primary_mpart,
> > +                                    u32 *secondary_mpart)
> > +{
> > +     int i, ret;
> > +     u32 nparts, mparts;
> > +     gpt_entry *gpt_pte = NULL;
> > +     const efi_guid_t fwu_metadata_guid = FWU_METADATA_GUID;
> > +
> > +     ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
> > +                                  desc->blksz);
> > +
> > +     ret = get_gpt_hdr_parts(desc, gpt_head, &gpt_pte);
> > +     if (ret < 0) {
> > +             log_err("Error getting GPT header and partitions\n");
> > +             ret = -EIO;
> > +             goto out;
> > +     }
> > +
> > +     nparts = gpt_head->num_partition_entries;
> > +     for (i = 0, mparts = 0; i < nparts; i++) {
> > +             if (!guidcmp(&fwu_metadata_guid,
> > +                          &gpt_pte[i].partition_type_guid)) {
> > +                     ++mparts;
> > +                     if (!*primary_mpart)
> > +                             *primary_mpart = i + 1;
> > +                     else
> > +                             *secondary_mpart = i + 1;
> > +             }
> > +     }
> > +
> > +     if (mparts != 2) {
> > +             log_err("Expect two copies of the metadata instead of
> %d\n",
> > +                     mparts);
> > +             ret = -EINVAL;
> > +     } else {
> > +             ret = 0;
> > +     }
> > +out:
> > +     free(gpt_pte);
> > +
> > +     return ret;
> > +}
> > +
> > +static int gpt_get_metadata_disk_part(struct blk_desc *desc,
> > +                                   struct disk_partition *info,
> > +                                   u32 part_num)
> > +{
> > +     int ret;
> > +     char *metadata_guid_str = "8a7a84a0-8387-40f6-ab41-a8b9a5a60d23";
>
> Is this hard-code guid_string intentioned?
>

Yes, this is mentioned in the FWU spec[1], Table 3, pg 14.

-sughosh

[1] - https://developer.arm.com/documentation/den0118/a


>
> > +
> > +     ret = part_get_info(desc, part_num, info);
>
> Jason Liu
>