[U-Boot] [PATCH v1 1/2] part_efi: support padding between the GPT header and partition entries
Philipp Tomsich
philipp.tomsich at theobroma-systems.com
Fri Feb 17 17:31:30 UTC 2017
Some architectures require their SPL loader at a fixed address within
the first 16KB of the disk. To avoid an overlap with the partition
entries of the EFI partition table, the first safe offset (in bytes,
from the start of the device) for the entries can be set through
CONFIG_EFI_PARTITION_ENTRIES_OFF.
When formatting a device with an EFI parition table, we may need to
leave a gap between the GPT header (always in LBA 1) and the partition
entries. The GPT header already contains a field to specify the
on-disk location, which has so far always been set to LBA 2. With this
change, a configurable offset will be translated into a LBA address
indicating where to put the entries.
Now also allows an override via device-tree using a config-node.
Tested (exporting an internal MMC formatted with this) against Linux,
MacOS X and Windows.
Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
---
disk/part_efi.c | 46 ++++++++++++++++++++++++++++++++++++++++----
scripts/config_whitelist.txt | 1 +
2 files changed, 43 insertions(+), 4 deletions(-)
diff --git a/disk/part_efi.c b/disk/part_efi.c
index 893cbbd..7c4ae69 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -1,22 +1,23 @@
/*
* Copyright (C) 2008 RuggedCom, Inc.
* Richard Retanubun <RichardRetanubun at RuggedCom.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* NOTE:
* when CONFIG_SYS_64BIT_LBA is not defined, lbaint_t is 32 bits; this
* limits the maximum size of addressable storage to < 2 Terra Bytes
*/
#include <asm/unaligned.h>
#include <common.h>
#include <command.h>
+#include <fdtdec.h>
#include <ide.h>
#include <inttypes.h>
#include <malloc.h>
#include <memalign.h>
#include <part_efi.h>
#include <linux/ctype.h>
@@ -350,48 +351,48 @@ static int set_protective_mbr(struct blk_desc *dev_desc)
int write_gpt_table(struct blk_desc *dev_desc,
gpt_header *gpt_h, gpt_entry *gpt_e)
{
const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
* sizeof(gpt_entry)), dev_desc);
u32 calc_crc32;
debug("max lba: %x\n", (u32) dev_desc->lba);
/* Setup the Protective MBR */
if (set_protective_mbr(dev_desc) < 0)
goto err;
/* Generate CRC for the Primary GPT Header */
calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
le32_to_cpu(gpt_h->num_partition_entries) *
le32_to_cpu(gpt_h->sizeof_partition_entry));
gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
le32_to_cpu(gpt_h->header_size));
gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
/* Write the First GPT to the block right after the Legacy MBR */
if (blk_dwrite(dev_desc, 1, 1, gpt_h) != 1)
goto err;
- if (blk_dwrite(dev_desc, 2, pte_blk_cnt, gpt_e)
- != pte_blk_cnt)
+ if (blk_dwrite(dev_desc, le64_to_cpu(gpt_h->partition_entry_lba),
+ pte_blk_cnt, gpt_e) != pte_blk_cnt)
goto err;
prepare_backup_gpt_header(gpt_h);
if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
+ 1, pte_blk_cnt, gpt_e) != pte_blk_cnt)
goto err;
if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
gpt_h) != 1)
goto err;
debug("GPT successfully written to block device!\n");
return 0;
err:
printf("** Can't write to device %d **\n", dev_desc->devnum);
return -1;
}
@@ -498,25 +499,62 @@ int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
return 0;
}
+static uint32_t partition_entries_offset(struct blk_desc *dev_desc)
+{
+ uint32_t offset_blks;
+ int config_offset;
+
+#if defined(CONFIG_EFI_PARTITION_ENTRIES_OFF)
+ /* Some architectures require their SPL loader at a fixed
+ * address within the first 16KB of the disk. To avoid an
+ * overlap with the partition entries of the EFI partition
+ * table, the first safe offset (in bytes, from the start of
+ * the disk) for the entries can be set in
+ * CONFIG_EFI_PARTITION_ENTRIES_OFF.
+ */
+ offset_blks =
+ PAD_TO_BLOCKSIZE(CONFIG_EFI_PARTITION_ENTRIES_OFF, dev_desc);
+#else
+ offset_blks = 2;
+#endif
+
+#if defined(CONFIG_OF_LIBFDT)
+ /* Allow the offset of the first partition entires (in bytes
+ from the start of the device) to be specified as a property
+ of the device tree '/config' node. */
+ config_offset = fdtdec_get_config_int(gd->fdt_blob,
+ "u-boot,efi-partition-entries-offset",
+ -EINVAL);
+ if (config_offset != -EINVAL)
+ offset_blks = PAD_TO_BLOCKSIZE(config_offset, dev_desc);
+#endif
+
+ debug("efi: partition entries offset (in blocks): %d\n", offset_blks);
+
+ return offset_blks;
+}
+
int gpt_fill_header(struct blk_desc *dev_desc, gpt_header *gpt_h,
char *str_guid, int parts_count)
{
gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
gpt_h->my_lba = cpu_to_le64(1);
gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
- gpt_h->first_usable_lba = cpu_to_le64(34);
gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
- gpt_h->partition_entry_lba = cpu_to_le64(2);
+ gpt_h->partition_entry_lba =
+ cpu_to_le64(partition_entries_offset(dev_desc));
+ gpt_h->first_usable_lba =
+ cpu_to_le64(le64_to_cpu(gpt_h->partition_entry_lba) + 32);
gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
gpt_h->header_crc32 = 0;
gpt_h->partition_entry_array_crc32 = 0;
if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
return -1;
return 0;
}
diff --git a/scripts/config_whitelist.txt b/scripts/config_whitelist.txt
index 6a09ad1..195af92 100644
--- a/scripts/config_whitelist.txt
+++ b/scripts/config_whitelist.txt
@@ -934,6 +934,7 @@ CONFIG_EEPRO100_SROM_WRITE
CONFIG_EEPROM_BUS_ADDRESS
CONFIG_EEPROM_CHIP_ADDRESS
CONFIG_EEPROM_LAYOUT_HELP_STRING
+CONFIG_EFI_PARTITION_ENTRIES_OFF
CONFIG_EFLASH_PROTSECTORS
CONFIG_EHCI_DESC_BIG_ENDIAN
CONFIG_EHCI_HCD_INIT_AFTER_RESET
--
1.9.1
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