separate halt() and idle()

Signed-off-by: Axel Heider <[email protected]>

include/util.h

@@ -128,6 +128,8 @@ void __builtin_unreachable(void);
         halt_spec: "\<Gamma> \<turnstile> {} Call halt_'proc {}"
 */
 void halt(void) NORETURN;
+void Arch_halt(void) NORETURN;
+
 void memzero(void *s, unsigned long n);
 void *memset(void *s, unsigned long c, unsigned long n) VISIBLE;
 void *memcpy(void *ptr_dst, const void *ptr_src, unsigned long n) VISIBLE;

src/arch/arm/32/config.cmake

@@ -16,6 +16,7 @@ add_sources(
         machine/fpu.c
         model/statedata.c
         c_traps.c
+        halt.c
         idle.c
         kernel/thread.c
         kernel/vspace.c

src/arch/arm/32/halt.c

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2014, General Dynamics C4 Systems
+ * Copyright 2021, Axel Heider <[email protected]>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <config.h>
+#include <util.h>
+
+void NORETURN Arch_halt(void)
+{
+    /* Disable interrupts and loop over WFI.
+     * ToDo: If the platform runs ATF, we could issue the PSCI call CPU_OFF. The
+     *       other nodes are still running, currently there is no way to halt
+     *       them also. ATF defines a PSCI call SYSTEM_OFF.
+     */
+    asm volatile("cpsid iaf");
+    for (;;) {
+        wfi();
+    }
+
+    UNREACHABLE();
+}

src/arch/arm/32/idle.c

@@ -5,8 +5,8 @@
  */
 
 #include <config.h>
+#include <util.h>
 #include <mode/machine.h>
-#include <api/debug.h>
 
 /*
  * The idle thread currently does not receive a stack pointer and so we rely on
@@ -24,19 +24,3 @@ void FORCE_O2 idle_thread(void)
         wfi();
     }
 }
-
-/** DONT_TRANSLATE */
-void NORETURN NO_INLINE VISIBLE halt(void)
-{
-    /* halt is actually, idle thread without the interrupts */
-    asm volatile("cpsid iaf");
-
-#ifdef CONFIG_PRINTING
-    printf("halting...");
-#ifdef CONFIG_DEBUG_BUILD
-    debug_printKernelEntryReason();
-#endif
-#endif
-    idle_thread();
-    UNREACHABLE();
-}

src/arch/arm/64/config.cmake

@@ -16,6 +16,7 @@ add_sources(
         machine/fpu.c
         model/statedata.c
         c_traps.c
+        halt.c
         idle.c
         kernel/thread.c
         kernel/vspace.c

src/arch/arm/64/halt.c

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
+ * Copyright 2021, Axel Heider <[email protected]>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+void NORETURN Arch_halt(void)
+{
+    /* Disable interrupts and loop over WFI.
+     * ToDo: If the platform runs ATF, we could issue the PSCI call CPU_OFF. The
+     *       other nodes are still running, currently there is no way to halt
+     *       them also. ATF defines a PSCI call SYSTEM_OFF that might be used.
+     */
+    MSR("daif", (DAIF_DEBUG | DAIF_SERROR | DAIF_IRQ | DAIF_FIRQ));
+    for (;;) {
+        wfi();
+    }
+
+    UNREACHABLE();
+}

src/arch/arm/64/idle.c

@@ -6,27 +6,10 @@
 
 #include <config.h>
 #include <mode/machine.h>
-#include <api/debug.h>
 
 void idle_thread(void)
 {
     while (1) {
         wfi();
     }
 }
-
-/** DONT_TRANSLATE */
-void NORETURN NO_INLINE VISIBLE halt(void)
-{
-    /* halt is actually, idle thread without the interrupts */
-    MSR("daif", (DAIF_DEBUG | DAIF_SERROR | DAIF_IRQ | DAIF_FIRQ));
-
-#ifdef CONFIG_PRINTING
-    printf("halting...");
-#ifdef CONFIG_DEBUG_BUILD
-    debug_printKernelEntryReason();
-#endif
-#endif
-    idle_thread();
-    UNREACHABLE();
-}

src/arch/riscv/config.cmake

@@ -95,6 +95,7 @@ add_sources(
     PREFIX src/arch/riscv
     CFILES
         c_traps.c
+        halt.c
         idle.c
         api/faults.c
         api/benchmark.c

src/arch/riscv/halt.c

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2015, 2016 Hesham Almatary <[email protected]>*
+ * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
+ * Copyright 2021, Axel Heider <[email protected]>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <config.h>
+#include <util.h>
+#include <arch/sbi.h>
+
+void NORETURN Arch_halt(void)
+{
+    /* Use SBI to halt the system.
+     * ToDo: Systems may not have an SBI, in this case disabling all interrupts
+     *       an looping over WFI is the best we can do.
+     */
+    sbi_shutdown();
+
+    UNREACHABLE();
+}

src/arch/riscv/idle.c

@@ -6,26 +6,10 @@
  */
 
 #include <config.h>
-#include <arch/sbi.h>
 
 void idle_thread(void)
 {
     while (1) {
         asm volatile("wfi");
     }
 }
-
-/** DONT_TRANSLATE */
-void VISIBLE NO_INLINE halt(void)
-{
-#ifdef CONFIG_PRINTING
-    printf("halting...");
-#ifdef CONFIG_DEBUG_BUILD
-    debug_printKernelEntryReason();
-#endif /* CONFIG_DEBUG_BUILD */
-#endif /* CONFIG_PRINTING */
-
-    sbi_shutdown();
-
-    UNREACHABLE();
-}

src/arch/x86/config.cmake

@@ -365,6 +365,7 @@ add_sources(
     PREFIX src/arch/x86
     CFILES
         c_traps.c
+        halt.c
         idle.c
         api/faults.c
         object/interrupt.c

src/arch/x86/halt.c

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
+ * Copyright 2021, Axel Heider <[email protected]>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <config.h>
+#include <util.h>
+
+void NORETURN Arch_halt(void)
+{
+    /* Disable interrupts and loop over HLT on this core.
+     * ToDo: The other nodes are still running, currently there is no way to
+     *       halt them also.
+     */
+    asm volatile("cli");
+    for (;;) {
+        asm volatile("hlt" ::: "memory");
+    }
+
+    UNREACHABLE();
+}

src/arch/x86/idle.c

@@ -5,7 +5,7 @@
  */
 
 #include <config.h>
-#include <api/debug.h>
+#include <util.h>
 
 /*
  * The idle thread does not have a dedicated stack and runs in
@@ -23,19 +23,3 @@ __attribute__((naked)) NORETURN void idle_thread(void)
         "jmp 1b"
     );
 }
-
-/** DONT_TRANSLATE */
-void VISIBLE halt(void)
-{
-    /* halt is actually, idle thread without the interrupts */
-    asm volatile("cli");
-
-#ifdef CONFIG_PRINTING
-    printf("halting...");
-#ifdef CONFIG_DEBUG_BUILD
-    debug_printKernelEntryReason();
-#endif
-#endif
-    idle_thread();
-    UNREACHABLE();
-}

src/util.c

@@ -8,6 +8,17 @@
 #include <stdint.h>
 #include <util.h>
 
+/** DONT_TRANSLATE */
+void NORETURN NO_INLINE VISIBLE halt(void)
+{
+    printf("halting...");
+#ifdef CONFIG_DEBUG_BUILD
+    debug_printKernelEntryReason();
+#endif /* CONFIG_DEBUG_BUILD */
+    Arch_halt(); /* This must not return. */
+    UNREACHABLE();
+}
+
 /*
  * memzero needs a custom type that allows us to use a word
  * that has the aliasing properties of a char.