arm64/sctlr: Allows thread to independent control the switch of sctlr

The method is the same as the method of saving the current DAIF state of the thread
It will pave the way for the future implementation of hwasan's memory management
Allows each thread to independently control the mte switch function

Signed-off-by: wangmingrong1 <wangmingrong1@xiaomi.com>

arch/arm64/include/irq.h

@@ -153,10 +153,11 @@
 #define REG_SPSR            (33)
 #define REG_SP_EL0          (34)
 #define REG_EXE_DEPTH       (35)
+#define REG_SCTLR_EL1       (36)
 
 /* In Armv8-A Architecture, the stack must align with 16 byte */
 
-#define ARM64_CONTEXT_REGS  (36)
+#define ARM64_CONTEXT_REGS  (37)
 #define ARM64_CONTEXT_SIZE  (8 * ARM64_CONTEXT_REGS)
 
 #ifdef CONFIG_ARCH_FPU

arch/arm64/src/common/arm64_initialstate.c

@@ -86,6 +86,11 @@ void arm64_new_task(struct tcb_s * tcb)
   xcp->regs[REG_SPSR]      = SPSR_MODE_EL1H;
 #endif
 
+  xcp->regs[REG_SCTLR_EL1] = read_sysreg(sctlr_el1);
+#ifdef CONFIG_ARM64_MTE
+  xcp->regs[REG_SCTLR_EL1] |= SCTLR_TCF1_BIT;
+#endif
+
 #ifdef CONFIG_SUPPRESS_INTERRUPTS
   xcp->regs[REG_SPSR]     |= (DAIF_IRQ_BIT | DAIF_FIQ_BIT);
 #endif /* CONFIG_SUPPRESS_INTERRUPTS */

arch/arm64/src/common/arm64_vector_table.S

@@ -80,9 +80,12 @@
 #endif
     stp    \xreg0, \xreg1,  [sp, #8 * REG_ELR]
 
+    mrs    \xreg0, sctlr_el1
+    str    \xreg0,  [sp, #8 * REG_SCTLR_EL1]
+
     mrs    \xreg0, sp_el0
     mrs    \xreg1, tpidrro_el0
-    stp    \xreg0, \xreg1,  [sp, #8 * REG_SP_EL0]
+    stp    \xreg0, \xreg1, [sp, #8 * REG_SP_EL0]
 
     /* Increment exception depth */
 
@@ -268,6 +271,9 @@ SECTION_FUNC(text, arm64_exit_exception)
     msr    spsr_el1,  x1
 #endif
 
+    ldr    x0,   [sp, #8 * REG_SCTLR_EL1]
+    msr    sctlr_el1, x0
+
     ldp    x0, x1,   [sp, #8 * REG_SP_EL0]
     msr    sp_el0,   x0
     msr    tpidrro_el0,  x1

arch/arm64/src/common/arm64_vectors.S

@@ -84,6 +84,9 @@ SECTION_FUNC(text, up_saveusercontext)
 #endif
     stp    x4,  x5,  [x0, #8 * REG_ELR]
 
+    mrs    x4,  sctlr_el1
+    str    x4,  [x0, #8 * REG_SCTLR_EL1]
+
     ret
 
 /****************************************************************************
@@ -115,6 +118,8 @@ SECTION_FUNC(text, arm64_jump_to_user)
     and x0,  x0, #~SPSR_MODE_MASK
     #orr x0, x0, #SPSR_MODE_EL0T # EL0T=0x00, out of range for orr
     str x0,  [sp, #8 * REG_SPSR]
+    mrs x0,  sctlr_el1
+    str x0,  [sp, #8 * REG_SCTLR_EL1]
     b arm64_exit_exception
 #endif