Hi Denis,
On 6/5/26 5:39 AM, [email protected] wrote:
From: Denis Mukhin <[email protected]>
Add common helper to decode/encode ChromuimOS-style GPT attributes
similarly to [1].
[1]
https://chromium.googlesource.com/chromiumos/platform/vboot_reference/+/master/cgpt
Can you tell us *which* commit you used in the commit log. I'm assuming
master is a moving branch so this makes it harder to look for future fixes.
Signed-off-by: Denis Mukhin <[email protected]>
---
include/cros_flags.h | 74 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 74 insertions(+)
create mode 100644 include/cros_flags.h
diff --git a/include/cros_flags.h b/include/cros_flags.h
new file mode 100644
index 000000000000..e9355fa5e908
--- /dev/null
+++ b/include/cros_flags.h
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Bit definitions and masks for GPT attributes for Chromium OS.
+ *
+ * 63-61 -- (reserved)
+ * 60 -- read-only
+ * 59-58 -- (reserved)
+ * 57 -- error counter
+ * 56 -- success
+ * 55-52 -- tries
+ * 51-48 -- priority
+ * 47-3 -- UEFI: reserved for future use
+ * 2 -- UEFI: Legacy BIOS bootable
+ * 1 -- UEFI: partition is not mapped
+ * 0 -- UEFI: partition is required
+ *
+ * Reference:
+ *
https://chromium.googlesource.com/chromiumos/platform/vboot_reference/+/master/cgpt
Possibly here as well so we don't get confused if this differs from
master of vboot in years from now?
+ */
+
+#ifndef _CROS_FLAGS_H
+#define _CROS_FLAGS_H
+
+#define CROS_FLAG_PRIORITY_MASK 0x000fU
+#define CROS_FLAG_TRIES_MASK 0x00f0U
+#define CROS_FLAG_SUCCESSFUL_MASK 0x0100U
+
+#define CROS_FLAG_PRIORITY_SHIFT 0U
+#define CROS_FLAG_TRIES_SHIFT 4U
+#define CROS_FLAG_SUCCESSFUL_SHIFT 8U
+
+static inline unsigned int
+cros_flags_get_priority(unsigned int flags)
+{
+ return (flags & CROS_FLAG_PRIORITY_MASK) >> CROS_FLAG_PRIORITY_SHIFT;
+}
+
+static inline unsigned int
+cros_flags_set_priority(unsigned int flags, unsigned int priority)
+{
+ flags &= ~CROS_FLAG_PRIORITY_MASK;
+ flags |= (priority & 0xf) << CROS_FLAG_PRIORITY_SHIFT;
+ return flags;
+}
+
+static inline unsigned int
+cros_flags_get_tries(unsigned int flags)
+{
+ return (flags & CROS_FLAG_TRIES_MASK) >> CROS_FLAG_TRIES_SHIFT;
+}
+
+static inline unsigned int
+cros_flags_set_tries(unsigned int flags, unsigned int tries)
+{
+ flags &= ~CROS_FLAG_TRIES_MASK;
+ flags |= (tries & 0xf) << CROS_FLAG_TRIES_SHIFT;
+ return flags;
+}
+
+static inline bool
+cros_flags_get_successful(unsigned int flags)
+{
+ return (flags & CROS_FLAG_SUCCESSFUL_MASK) >>
CROS_FLAG_SUCCESSFUL_SHIFT;
+}
+
+static inline unsigned int
+cros_flags_set_successful(unsigned int flags, bool ok)
+{
+ flags &= ~CROS_FLAG_SUCCESSFUL_MASK;
+ flags |= ok << CROS_FLAG_SUCCESSFUL_SHIFT;
+ return flags;
+}
+
+#endif /* _CROS_FLAGS_H */
Would it make sense to use the nice GENMASK, FIELD_GET, FIELD_PREP
macros from Linux for bitfield and masks?
Cheers,
Quentin
