Changeset 06f10ac in mainline for kernel/arch/arm64/include/arch/istate_struct.h

Timestamp:

2021-08-22T19:08:44Z (3 years ago)

Author:

Martin Decky <martin@…>

Branches:

master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

c21cc26

Parents:

95b7d4df

Message:

Implement support for HiKey 960

Initial support for the 96Boards HiKey 960 board.

• The kernel identity mapping has been extended to 4 GiB. The initial bootstrap mapping maps 3 GiB as nornal memory and the next 1 GiB as device memory to support early UART debugging output.

• The istate_t has been padded in order to preserve the stack pointer alignment invariant.

The current implementation is limited to UP and UART input/output.

File:

• kernel/arch/arm64/include/arch/istate_struct.h (modified) (2 diffs)

kernel/arch/arm64/include/arch/istate_struct.h

@@ -65 +65 @@
 #define ISTATE_OFFSET_X29    0x108
 #define ISTATE_OFFSET_X30    0x110
-#define ISTATE_SIZE          0x118
+#define ISTATE_OFFSET_PAD0   0x118
+#define ISTATE_SIZE          0x120
 
 #ifndef __ASSEMBLER__
@@ -109 +110 @@
         /* Link Register. */
         uint64_t x30;
+
+        /*
+         * ARM64 mandates that the stack pointer is always aligned to
+         * a 16-byte boundary. To satisfy this condition, the size of
+         * this data structure needs to be also a multiple of 16 bytes.
+         * This is the reason for this padding.
+         */
+        uint64_t pad0;
 } istate_t;
 
 #endif
+
 #endif