power: Add ARC core suspend and resume support

When going into DEEP_SLEEP mode, the ARC core now saves
its context. This includes:
- All core registers
- Stack pointer
- Program counter (restored by jumping to the restore code)

The arc reset code now checks if the GPS0 bit 2 is set.
This is similar to the behavior of the x86 core done by
the QMSI bootloader which is setting GPS0 bit 1 in order
to call the restore path instead of cold boot path.

The sample has been adapted in order to support the ARC.

Jira: ZEP-1222

Change-Id: I375f03b16b8a5fd1f07ead55cf7e4947d6290c9f
Signed-off-by: Julien Delayen <julien.delayen@intel.com>

arch/arc/core/Makefile

@@ -4,7 +4,7 @@ ccflags-y +=-I$(srctree)/arch/$(ARCH)/include
 obj-y += thread.o thread_entry_wrapper.o \
 	cpu_idle.o  fast_irq.o  fatal.o  fault.o  \
 	fault_s.o  irq_manage.o cache.o  \
-	isr_wrapper.o  regular_irq.o  swap_macros.h  swap.o \
+	isr_wrapper.o  regular_irq.o  swap.o \
 	sys_fatal_error_handler.o
 
 obj-y += prep_c.o \

arch/arc/core/fast_irq.S

@@ -29,7 +29,7 @@
 #include <offsets_short.h>
 #include <toolchain.h>
 #include <arch/cpu.h>
-#include "swap_macros.h"
+#include <swap_macros.h>
 
 GTEXT(_firq_enter)
 GTEXT(_firq_exit)

arch/arc/core/fault_s.S

@@ -26,7 +26,7 @@
 #include <toolchain.h>
 #include <sections.h>
 #include <arch/cpu.h>
-#include "swap_macros.h"
+#include <swap_macros.h>
 
 GTEXT(_Fault)
 

arch/arc/core/regular_irq.S

@@ -30,7 +30,7 @@
 #include <offsets_short.h>
 #include <toolchain.h>
 #include <arch/cpu.h>
-#include "swap_macros.h"
+#include <swap_macros.h>
 
 GTEXT(_rirq_enter)
 GTEXT(_rirq_exit)

arch/arc/core/reset.S

@@ -99,6 +99,11 @@ invalidate_dcache:
 
 done_cache_invalidate:
 
+#if defined(CONFIG_SYS_POWER_DEEP_SLEEP) && \
+	!defined(CONFIG_BOOTLOADER_CONTEXT_RESTORE)
+        jl @_sys_soc_resume_from_deep_sleep
+#endif
+
 #ifdef CONFIG_INIT_STACKS
 	/*
 	 * use the main stack to call memset on the interrupt stack and the

arch/arc/core/swap.S

@@ -31,7 +31,7 @@
 #include <toolchain.h>
 #include <arch/cpu.h>
 #include <v2/irq.h>
-#include "swap_macros.h"
+#include <swap_macros.h>
 
 GTEXT(_Swap)
 GTEXT(_get_next_ready_thread)

arch/arc/include/swap_macros.h

@@ -155,8 +155,8 @@ extern "C" {
 	 *
 	 * The pc and status32 values will still be on the stack. We cannot
 	 * pop them yet because the callers of _pop_irq_stack_frame must reload
-	 * status32 differently depending on the execution context they are running
-	 * in (_Swap(), firq or exception).
+	 * status32 differently depending on the execution context they are
+	 * running in (_Swap(), firq or exception).
 	 */
 	add_s sp, sp, ___isf_t_SIZEOF
 

arch/arc/soc/quark_se_c1000_ss/Kbuild

@@ -6,4 +6,4 @@ ccflags-$(CONFIG_ADC) +=-I$(srctree)/drivers/adc
 
 asflags-y := ${ccflags-y}
 
-obj-y = soc.o soc_config.o power.o
+obj-y = soc.o soc_config.o soc_power.o power.o

arch/arc/soc/quark_se_c1000_ss/Kconfig.soc

@@ -2,4 +2,5 @@
 config SOC_QUARK_SE_C1000_SS
 	bool "Intel Quark SE C1000- Sensor Sub System"
 	select SYS_POWER_LOW_POWER_STATE_SUPPORTED
+	select SYS_POWER_DEEP_SLEEP_SUPPORTED
 	select HAS_QMSI

arch/arc/soc/quark_se_c1000_ss/power.c

@@ -22,7 +22,30 @@
 #include <init.h>
 #include <kernel_structs.h>
 
+#include "power_states.h"
 #include "ss_power_states.h"
+#include "vreg.h"
+
+#if (defined(CONFIG_SYS_POWER_DEEP_SLEEP))
+extern void _power_soc_sleep(void);
+extern void _power_soc_deep_sleep(void);
+
+static void _deep_sleep(enum power_states state)
+{
+	power_soc_set_ss_restore_flag();
+
+	switch (state) {
+	case SYS_POWER_STATE_DEEP_SLEEP_1:
+		_power_soc_sleep();
+		break;
+	case SYS_POWER_STATE_DEEP_SLEEP:
+		_power_soc_deep_sleep();
+		break;
+	default:
+		break;
+	}
+}
+#endif
 
 #define SLEEP_MODE_CORE_OFF (0x0)
 #define SLEEP_MODE_CORE_TIMERS_RTC_OFF (0x60)
@@ -57,10 +80,12 @@ void _sys_soc_set_power_state(enum power_states state)
 	case SYS_POWER_STATE_CPU_LPS_2:
 		enter_arc_state(ARC_SS1);
 		break;
+#if (defined(CONFIG_SYS_POWER_DEEP_SLEEP))
 	case SYS_POWER_STATE_DEEP_SLEEP:
 	case SYS_POWER_STATE_DEEP_SLEEP_1:
-		/* Sleep states are not yet supported for ARC. */
+		_deep_sleep(state);
 		break;
+#endif
 	default:
 		break;
 	}
@@ -78,6 +103,10 @@ void _sys_soc_power_state_post_ops(enum power_states state)
 		limit = _arc_v2_aux_reg_read(_ARC_V2_TMR0_LIMIT);
 		_arc_v2_aux_reg_write(_ARC_V2_TMR0_COUNT, limit - 1);
 		break;
+	case SYS_POWER_STATE_DEEP_SLEEP:
+	case SYS_POWER_STATE_DEEP_SLEEP_1:
+		__builtin_arc_seti(0);
+		break;
 	default:
 		break;
 	}

arch/arc/soc/quark_se_c1000_ss/soc_power.S

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2016 Intel Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define _ASMLANGUAGE
+
+#include <toolchain.h>
+#include <arch/arc/v2/aux_regs.h>
+#include <swap_macros.h>
+
+#ifdef CONFIG_SYS_POWER_DEEP_SLEEP
+GDATA(_pm_arc_context)
+
+GTEXT(_sys_soc_resume_from_deep_sleep)
+GTEXT(_power_restore_cpu_context)
+GTEXT(_power_soc_sleep)
+GTEXT(_power_soc_deep_sleep)
+
+#define GPS0_REGISTER  0xb0800100
+#define RESTORE_SS_BIT 2
+
+SECTION_FUNC(TEXT, _sys_soc_resume_from_deep_sleep)
+        /* Check is this wakeup after sleep event. */
+        ld r0,[GPS0_REGISTER]
+        bbit1 r0,RESTORE_SS_BIT,restore
+	j_s [blink] /* Jump to context of BLINK register. */
+
+restore:
+        bclr_s r0,r0,RESTORE_SS_BIT
+        st r0,[GPS0_REGISTER]
+
+	/* Enable I-Cache */
+        sr 1, [_ARC_V2_IC_CTRL]
+
+	j @_sys_soc_restore_cpu_context
+
+SECTION_FUNC(TEXT, save_cpu_context)
+	mov_s r1, _kernel
+	ld_s r2, [r1, _kernel_offset_to_current]
+
+	_save_callee_saved_regs
+
+	j_s [blink] /* Jump to context of BLINK register. */
+
+SECTION_FUNC(TEXT, _power_soc_sleep)
+	/*
+	 * Save the return address.
+	 * The restore function will pop this and jump
+	 * back to the caller.
+	 */
+	push_s blink
+
+	/* Do not link to preserve blink */
+	jl @save_cpu_context
+	j @power_soc_sleep
+	/* Does not return */
+
+SECTION_FUNC(TEXT, _power_soc_deep_sleep)
+	/*
+	 * Save the return address.
+	 * The restore function will pop this and jump
+	 * back to the caller.
+	 */
+	push_s blink
+
+	/* Do not link to preserve blink */
+	jl @save_cpu_context
+	j @power_soc_deep_sleep
+	/* Does not return */
+
+SECTION_FUNC(TEXT, _sys_soc_restore_cpu_context)
+	mov_s r1, _kernel
+	ld_s r2, [r1, _kernel_offset_to_current]
+
+	_load_callee_saved_regs
+
+	/* Restore return address */
+	pop_s blink
+
+	j_s [blink] /* Jump to context of BLINK register. */
+#endif

ext/hal/qmsi/Kbuild

@@ -1,6 +1,7 @@
 obj-$(CONFIG_QMSI_BUILTIN) += drivers/flash/qm_flash.o
-ifeq ($(CONFIG_ARC),y)
+ifeq ($(CONFIG_SOC_QUARK_SE_C1000_SS),y)
 obj-$(CONFIG_QMSI_BUILTIN) += drivers/clk/ss_clk.o
+obj-$(CONFIG_QMSI_BUILTIN) += soc/quark_se/drivers/vreg.o
 obj-$(CONFIG_QMSI_BUILTIN) += soc/quark_se/drivers/ss_power_states.o
 endif
 obj-$(CONFIG_QMSI_BUILTIN) += soc/$(patsubst %_ss,%,$(SOC_SERIES))/drivers/power_states.o
@@ -25,4 +26,4 @@ obj-$(CONFIG_SPI_QMSI_SS) += drivers/spi/qm_ss_spi.o
 obj-$(CONFIG_GPIO_QMSI_SS) += drivers/gpio/qm_ss_gpio.o
 obj-$(CONFIG_I2C_QMSI_SS) += drivers/i2c/qm_ss_i2c.o
 obj-$(CONFIG_ADC_QMSI_SS) += drivers/adc/qm_ss_adc.o
-obj-$(CONFIG_SOC_WATCH) += drivers/soc_watch.o
+obj-$(CONFIG_SOC_WATCH) += drivers/soc_watch.o

tests/power/power_states/src/main.c

@@ -351,6 +351,7 @@ static void build_suspend_device_list(void)
 		return;
 	}
 
+#if (CONFIG_X86)
 	suspend_device_count = 3;
 	for (i = 0; i < devcount; i++) {
 		if (!strcmp(devices[i].config->name, "loapic")) {
@@ -364,6 +365,18 @@ static void build_suspend_device_list(void)
 			suspend_devices[suspend_device_count++] = &devices[i];
 		}
 	}
+#elif (CONFIG_ARC)
+	suspend_device_count = 2;
+	for (i = 0; i < devcount; i++) {
+		if (!strcmp(devices[i].config->name, "arc_v2_irq_unit")) {
+			suspend_devices[0] = &devices[i];
+		} else if (!strcmp(devices[i].config->name, "sys_clock")) {
+			suspend_devices[1] = &devices[i];
+		} else {
+			suspend_devices[suspend_device_count++] = &devices[i];
+		}
+	}
+#endif
 }
 
 void main(void)