Refactor ARMv8.3 Pointer Authentication support code
This patch provides the following features and makes modifications
listed below:
- Individual APIAKey key generation for each CPU.
- New key generation on every BL31 warm boot and TSP CPU On event.
- Per-CPU storage of APIAKey added in percpu_data[]
of cpu_data structure.
- `plat_init_apiakey()` function replaced with `plat_init_apkey()`
which returns 128-bit value and uses Generic timer physical counter
value to increase the randomness of the generated key.
The new function can be used for generation of all ARMv8.3-PAuth keys
- ARMv8.3-PAuth specific code placed in `lib\extensions\pauth`.
- New `pauth_init_enable_el1()` and `pauth_init_enable_el3()` functions
generate, program and enable APIAKey_EL1 for EL1 and EL3 respectively;
pauth_disable_el1()` and `pauth_disable_el3()` functions disable
PAuth for EL1 and EL3 respectively;
`pauth_load_bl31_apiakey()` loads saved per-CPU APIAKey_EL1 from
cpu-data structure.
- Combined `save_gp_pauth_registers()` function replaces calls to
`save_gp_registers()` and `pauth_context_save()`;
`restore_gp_pauth_registers()` replaces `pauth_context_restore()`
and `restore_gp_registers()` calls.
- `restore_gp_registers_eret()` function removed with corresponding
code placed in `el3_exit()`.
- Fixed the issue when `pauth_t pauth_ctx` structure allocated space
for 12 uint64_t PAuth registers instead of 10 by removal of macro
CTX_PACGAKEY_END from `include/lib/el3_runtime/aarch64/context.h`
and assigning its value to CTX_PAUTH_REGS_END.
- Use of MODE_SP_ELX and MODE_SP_EL0 macro definitions
in `msr spsel` instruction instead of hard-coded values.
- Changes in documentation related to ARMv8.3-PAuth and ARMv8.5-BTI.
Change-Id: Id18b81cc46f52a783a7e6a09b9f149b6ce803211
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
diff --git a/include/lib/extensions/pauth.h b/include/lib/extensions/pauth.h
new file mode 100644
index 0000000..2e780de
--- /dev/null
+++ b/include/lib/extensions/pauth.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef PAUTH_H
+#define PAUTH_H
+
+/*******************************************************************************
+ * ARMv8.3-PAuth support functions
+ ******************************************************************************/
+
+/* Disable ARMv8.3 pointer authentication in EL1/EL3 */
+void pauth_disable_el1(void);
+void pauth_disable_el3(void);
+
+#endif /* PAUTH_H */