arch: xtensa: add waiti wakeup hook

On some platforms there is a need to perform tasks after
coming back from waiti.

There is no central interrupts processing function in SOF.
Every interrupt is registered separaterly, so we need to execute
'wake up' functions in xtos interrupts handlers.

Signed-off-by: Janusz Jankowski <janusz.jankowski@linux.intel.com>

Author: jajanusz

src/arch/xtensa/Kconfig

@@ -17,4 +17,13 @@ config SMP
 	help
 	  Indicates that architecture uses multiple cores
 
+config WAKEUP_HOOK
+	bool
+	default n
+	help
+	  Enables hook that is called and after coming back from WAITI.
+	  This config should be selected by other platform-level configs.
+	  Platforms that use it, have to implement hook function
+	  platform_interrupt_on_wakeup.
+
 endmenu

src/arch/xtensa/drivers/CMakeLists.txt

@@ -1,3 +1,3 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
-add_local_sources(sof timer.c)
+add_local_sources(sof interrupt.c timer.c)

src/arch/xtensa/drivers/interrupt.c

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause
+//
+// Copyright(c) 2020 Intel Corporation. All rights reserved.
+//
+// Author: Janusz Jankowski <janusz.jankowski@linux.intel.com>
+
+#include <sof/drivers/interrupt.h>
+
+#if CONFIG_WAKEUP_HOOK
+void arch_interrupt_on_wakeup(void)
+{
+	platform_interrupt_on_wakeup();
+}
+#endif

src/arch/xtensa/include/arch/drivers/interrupt.h

@@ -14,6 +14,7 @@
 #include <xtensa/xtruntime.h>
 #include <stddef.h>
 #include <stdint.h>
+#include <config.h>
 
 static inline int arch_interrupt_register(int irq,
 	void (*handler)(void *arg), void *arg)
@@ -83,6 +84,10 @@ static inline void arch_interrupt_global_enable(uint32_t flags)
 		     :: "a" (flags) : "memory");
 }
 
+#if CONFIG_WAKEUP_HOOK
+void arch_interrupt_on_wakeup(void);
+#endif
+
 #endif /* __ARCH_DRIVERS_INTERRUPT_H__ */
 
 #else

src/arch/xtensa/include/arch/lib/wait.h

@@ -10,6 +10,7 @@
 
 #include <sof/debug/panic.h>
 #include <sof/drivers/interrupt.h>
+#include <sof/lib/clk.h>
 #include <ipc/trace.h>
 #include <config.h>
 #include <xtensa/xtruntime.h>

src/arch/xtensa/xtos/int-medpri-dispatcher.S

@@ -169,6 +169,8 @@ no_context:
  * number and exception stack frame), then call the interrupt handler.
  * Note: The callx12 preserves the original user task's a4..a15.*/
 
+	xtos_on_wakeup
+
 #if CONFIG_SMP
 	xtos_addr_percore_add	a12, xtos_interrupt_table, MAPINT(SINGLE_INT_NUM)*XIE_SIZE
 #else
@@ -228,6 +230,8 @@ no_context:
 	/* set interrupt task context */
 	xtos_task_ctx_store_percore	a11, a14
 
+	xtos_on_wakeup
+
 /* Loop to handle all pending interrupts. */
 
 LABEL(.L1,_loop0):

src/arch/xtensa/xtos/xea1/int-lowpri-dispatcher.S

@@ -159,6 +159,8 @@ no_context:
 	/* set interrupt task context */
 	xtos_task_ctx_store_percore	a11, a14
 
+	xtos_on_wakeup
+
 /* Loop to handle all pending interrupts. */
 
 LABEL(.L1,_loop0):

src/arch/xtensa/xtos/xea2/int-lowpri-dispatcher.S

@@ -159,6 +159,8 @@ no_context:
 	/* set interrupt task context */
 	xtos_task_ctx_store_percore	a11, a14
 
+	xtos_on_wakeup
+
 /* Loop to handle all pending interrupts. */
 
 LABEL(.L1,_loop0):

src/arch/xtensa/xtos/xtos-internal.h

@@ -494,6 +494,13 @@ XTOS_PENDING_OFS:	.space	4	/* _xtos_pending variable */
 	s32i		\ax, \ay, XTOS_TASK_CONTEXT_OFFSET
 	.endm
 
+	// Executes optional callback on wake up
+	.macro	xtos_on_wakeup
+#if CONFIG_WAKEUP_HOOK
+	call12 arch_interrupt_on_wakeup
+#endif
+	.endm
+
 #else /* !_ASMLANGUAGE && !__ASSEMBLER__ */
 
 /*