Make PAC demangling more generic
At the moment, address demangling is only used by the backtrace
functionality. However, at some point, other parts of the TF-A
codebase may want to use it.
The 'demangle_address' function is replaced with a single XPACI
instruction which is also added in 'do_crash_reporting()'.
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
Change-Id: I4424dcd54d5bf0a5f9b2a0a84c4e565eec7329ec
diff --git a/common/backtrace/backtrace.c b/common/backtrace/backtrace.c
index 506d4a4..907117f 100644
--- a/common/backtrace/backtrace.c
+++ b/common/backtrace/backtrace.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -37,47 +37,6 @@
uintptr_t return_addr;
};
-/*
- * Strip the Pointer Authentication Code (PAC) from the address to retrieve the
- * original one.
- *
- * The PAC field is stored on the high bits of the address and defined as:
- * - PAC field = Xn[54:bottom_PAC_bit], when address tagging is used.
- * - PAC field = Xn[63:56, 54:bottom_PAC_bit], without address tagging.
- *
- * With bottom_PAC_bit = 64 - TCR_ELx.TnSZ
- */
-#if ENABLE_PAUTH
-static uintptr_t demangle_address(uintptr_t addr)
-{
- unsigned int el, t0sz, bottom_pac_bit;
- uint64_t tcr, pac_mask;
-
- /*
- * Different virtual address space size can be defined for each EL.
- * Ensure that we use the proper one by reading the corresponding
- * TCR_ELx register.
- */
- el = get_current_el();
-
- if (el == 3U) {
- tcr = read_tcr_el3();
- } else if (el == 2U) {
- tcr = read_tcr_el2();
- } else {
- tcr = read_tcr_el1();
- }
-
- /* T0SZ = TCR_ELx[5:0] */
- t0sz = tcr & 0x1f;
- bottom_pac_bit = 64 - t0sz;
- pac_mask = (1ULL << bottom_pac_bit) - 1;
-
- /* demangle the address with the computed mask */
- return (addr & pac_mask);
-}
-#endif /* ENABLE_PAUTH */
-
static const char *get_el_str(unsigned int el)
{
if (el == 3U) {
@@ -104,9 +63,8 @@
* stack contains a PAC. It must be stripped to retrieve the return
* address.
*/
- addr = demangle_address(addr);
+ xpaci(addr);
#endif
-
if (el == 3U) {
ats1e3r(addr);
} else if (el == 2U) {
@@ -257,9 +215,8 @@
* the stack contains a PAC. It must be stripped to retrieve the
* return address.
*/
- call_site = demangle_address(call_site);
+ xpaci(call_site);
#endif
-
/*
* If the address is invalid it means that the frame record is
* probably corrupted.