quark_se: power_mgmt: Fixes a cpu context save bug (05a0c6fe) · Commits · Wenxi XU / zephyr

arch/x86/soc/intel_quark/quark_se/power.c

+15 −17

Original line number	Diff line number	Diff line
		@@ -30,15 +30,15 @@ uint64_t _pm_save_gdtr;
		uint64_t _pm_save_idtr;
		uint32_t _pm_save_esp;

		extern void _power_soc_sleep(void);
		extern void _power_restore_cpu_context(void);
		extern void _power_soc_deep_sleep(void);

		#if (defined(CONFIG_SYS_POWER_DEEP_SLEEP))
		static uint32_t __x86_restore_info = (uint32_t )CONFIG_BSP_SHARED_RAM_ADDR;

		static void _deep_sleep(enum power_states state)
		{
		int restore;

		__asm__ volatile ("wbinvd");

		/*
		* Setting resume vector inside the restore_cpu_context
		* function since we have nothing to do before cpu context
		@@ -47,24 +47,22 @@ static void _deep_sleep(enum power_states state)
		* can be done before cpu context is restored and control
		* transferred to _sys_soc_suspend.
		*/
		qm_x86_set_resume_vector(_sys_soc_restore_cpu_context,
		qm_x86_set_resume_vector(_power_restore_cpu_context,
		*__x86_restore_info);

		restore = _sys_soc_save_cpu_context();

		if (!restore) {
		power_soc_set_x86_restore_flag();

		switch (state) {
		case SYS_POWER_STATE_DEEP_SLEEP_1:
		power_soc_sleep();
		_power_soc_sleep();
		break;
		case SYS_POWER_STATE_DEEP_SLEEP:
		power_soc_deep_sleep();
		_power_soc_deep_sleep();
		break;
		default:
		break;
		}
		}
		}
		#endif

		void _sys_soc_set_power_state(enum power_states state)

arch/x86/soc/intel_quark/quark_se/soc_power.S

+33 −25

Original line number	Diff line number	Diff line
		@@ -23,30 +23,24 @@ GDATA(_pm_save_gdtr)
		GDATA(_pm_save_idtr)
		GDATA(_pm_save_esp)

		GTEXT(_sys_soc_save_cpu_context)
		GTEXT(_sys_soc_restore_cpu_context)
		GTEXT(_sys_soc_resume_from_deep_sleep)
		GTEXT(_power_restore_cpu_context)
		GTEXT(_power_soc_sleep)
		GTEXT(_power_soc_deep_sleep)

		SECTION_FUNC(TEXT, _sys_soc_save_cpu_context)
		SECTION_FUNC(TEXT, save_cpu_context)
		movl %esp, %eax /* save ptr to return address */

		pushf /* save flags */
		pusha /* save GPRs */

		movl %esp, _pm_save_esp /* save stack ptr */
		sidtl _pm_save_idtr /* save idtr */
		sgdtl _pm_save_gdtr /* save gdtr */

		pushl (%eax) /* push return address */

		xorl %eax, %eax /* 0 indicates saved context */
		ret

		SECTION_FUNC(TEXT, _sys_soc_restore_cpu_context)
		/*
		* Will transfer control to _sys_power_save_cpu_context,
		* from where it will return 1 indicating the function
		* is exiting after a context switch.
		*/
		SECTION_FUNC(TEXT, _power_restore_cpu_context)
		lgdtl _pm_save_gdtr /* restore gdtr */
		lidtl _pm_save_idtr /* restore idtr */
		movl _pm_save_esp, %esp /* restore saved stack ptr */
		@@ -54,18 +48,32 @@ SECTION_FUNC(TEXT, _sys_soc_restore_cpu_context)
		popf /* restore saved flags */

		/*
		* At this point context is restored as it was saved
		* in _sys_soc_save_cpu_context. The following ret
		* will emulate a return from that function. Move 1
		* to eax to emulate a return 1. The caller of
		* _sys_soc_save_cpu_context will identify it is
		* returning from a context restore based on the
		* return value = 1.
		* At this point the stack contents will be as follows:
		*
		* Saved context
		* ESP ---> Return address of save_cpu_context
		* Return address of _power_soc_sleep/deep_sleep
		*
		* We just popped the saved context. Next we pop out the address
		* of the caller of save_cpu_context.Then the ret would return
		* to caller of _power_soc_sleep or _power_soc_deep_sleep.
		*
		*/
		xorl %eax, %eax
		incl %eax
		addl $4, %esp
		ret

		SECTION_FUNC(TEXT, _power_soc_sleep)
		call save_cpu_context
		wbinvd
		call power_soc_sleep
		/* Does not return */

		SECTION_FUNC(TEXT, _power_soc_deep_sleep)
		call save_cpu_context
		wbinvd
		call power_soc_deep_sleep
		/* Does not return */

		/*
		* This is an example function to handle the deep sleep resume notification
		* in the absence of bootloader context restore support.
		@@ -78,8 +86,8 @@ SECTION_FUNC(TEXT, _sys_soc_restore_cpu_context)
		*/
		SECTION_FUNC(TEXT, _sys_soc_resume_from_deep_sleep)
		movl $CONFIG_BSP_SHARED_RAM_ADDR, %eax
		cmpl $_sys_soc_restore_cpu_context, (%eax)
		je _sys_soc_restore_cpu_context
		cmpl $_power_restore_cpu_context, (%eax)
		je _power_restore_cpu_context
		ret

		#endif

arch/x86/soc/intel_quark/quark_se/soc_power.h

+0 −29

Original line number	Diff line number	Diff line
		@@ -30,35 +30,6 @@ enum power_states {
		SYS_POWER_STATE_MAX
		};

		/**
		* @brief Save CPU context
		*
		* This function would save the CPU context in the stack. It
		* would also save the idtr and gdtr registers. When context is
		* restored by _sys_soc_restore_cpu_context(), control will be
		* transferred into this function where the context was originally
		* saved. The return values would indicate whether it is returning
		* after saving context or after a context restore transferred
		* control to it.
		*
		* @retval 0 Indicates it is returning after saving cpu context
		* @retval 1 Indicates cpu context restore transferred control to it.
		*/
		int _sys_soc_save_cpu_context(void);

		/**
		* @brief Restore CPU context
		*
		* This function would restore the CPU context that was saved in
		* the stack by _sys_soc_save_cpu_context(). It would also restore
		* the idtr and gdtr registers.
		*
		* After context is restored, control will be transferred into
		* _sys_soc_save_cpu_context() function where the context was originally
		* saved.
		*/
		FUNC_NORETURN void _sys_soc_restore_cpu_context(void);

		/**
		* @brief Put processor into low power state
		*

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