dartmonkey: Reintroduce sleep lines to RO

Change https://crrev.com/c/2657778 removed the sleep lines from RO
in an effort to minimize the RO complexity.
Most notably, this isolated the deep-sleep/low-power-idle
logic to RW only.

Unfortunately, the sleep lines also control whether the SPI host interface
is listening, which allows it to ignore spurious communication.

It seems safer to reinstate the the sleep line with low power idle
active and directly disable CONFIG_LOW_POWER_IDLE in subsequent CL.

We reinstate the sleep line gpio logic from the following:
crrev.com/c1b5095aa8404709bb447bd7a58f262d7d471a01/board/nocturne_fp/board.c
This is the parent commit to the CL that refactors the sleep lines.

Considering dartmonkey has a sleep line modification for dev boards,
we keep this in RW only. Since nearly all functionality would need
to be conditioned and communicated between RO and RW, I decided to
just create a clean break between RO and RW board init. The original
board.c no longer spans both RO and RW, there are exclusive board_ro.c
and board_rw.c files.

BRANCH=none
BUG=b:178746753, b:195718112
TEST=make -j tests-dartmonkey
TEST=# Connect servo_micro and J-Link to an icetower board.
     make proj-dartmonkey -j
     sudo servod --board=icetower
     ./util/flash_jlink.py --board=dartmonkey --image=./build/dartmonkey/ec.bin
     # Unplug J-Link and unplug/replug servo connector.

     dut-control fpmcu_slp:off fpmcu_slp_alt:off
     dut-control pp3300_dx_mcu_mw # Should be more than 40mw
     dut-control fpmcu_slp:on fpmcu_slp_alt:off
     dut-control pp3300_dx_mcu_mw # Should be less than 10mw
     dut-control fpmcu_slp:off fpmcu_slp_alt:on
     dut-control pp3300_dx_mcu_mw # Should be less than 10mw
     dut-control fpmcu_slp:on fpmcu_slp_alt:on
     dut-control pp3300_dx_mcu_mw # Should be less than 10mw
     dut-control fpmcu_slp:off fpmcu_slp_alt:off

     minicom -D$(dut-control -o raw_fpmcu_console_uart_pty)
     > reboot ro
     # Ctrl-A Q

     # RO does not have the code to adjust to SLP_ALT_DEV_L, thus
     # it will use SLP_ALT_L, which is 0. This means it will always
     # think sleep is asserted.
     dut-control fpmcu_slp:off fpmcu_slp_alt:off
     dut-control pp3300_dx_mcu_mw # Should be less than 10mw
     minicom -D$(dut-control -o raw_fpmcu_console_uart_pty)
     > gpioget
     # Should see SLP_L=1, SLP_ALT_L=0, and SLP_ALT_DEV_L=1
     > reboot
     > fpenroll
     > fpmatch
     # Ctrl-A Q

Signed-off-by: Craig Hesling <hesling@chromium.org>
Change-Id: I6183a4afa61817c552da5272f7d66a5c58d96f66
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3078824
Reviewed-by: Josie Nordrum <josienordrum@google.com>

8 files changed, 102 insertions, 45 deletions

diff --git a/board/nocturne_fp/board.c b/board/nocturne_fp/board.c
deleted file mode 100644
index 819c1c53e0..0000000000
--- a/board/nocturne_fp/board.c
+++ /dev/null
@@ -1,37 +0,0 @@
-/* Copyright 2017 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-/* Meowth Fingerprint MCU configuration */
-
-#include "common.h"
-#include "hooks.h"
-#include "registers.h"
-#include "spi.h"
-#include "system.h"
-#include "task.h"
-
-/**
- * Disable restricted commands when the system is locked.
- *
- * @see console.h system.c
- */
-int console_is_restricted(void)
-{
-	return system_is_locked();
-}
-
-#include "gpio_list.h"
-
-/* Initialize board. */
-static void board_init(void)
-{
-	if (IS_ENABLED(SECTION_IS_RW)) {
-		board_init_rw();
-	} else {
-		/* No suspend-based power management in RO. */
-		disable_sleep(SLEEP_MASK_AP_RUN);
-		hook_notify(HOOK_CHIPSET_RESUME);
-	}
-}
-DECLARE_HOOK(HOOK_INIT, board_init, HOOK_PRIO_DEFAULT);
diff --git a/board/nocturne_fp/board.h b/board/nocturne_fp/board.h
index c30b4b76e0..6da68130df 100644
--- a/board/nocturne_fp/board.h
+++ b/board/nocturne_fp/board.h
@@ -186,6 +186,8 @@
 #include "gpio_signal.h"
 #include "board_rw.h"
 
+void slp_event(enum gpio_signal signal);
+
 #endif /* !__ASSEMBLER__ */
 
 #endif /* __BOARD_H */
diff --git a/board/nocturne_fp/board_ro.c b/board/nocturne_fp/board_ro.c
new file mode 100644
index 0000000000..7f20002435
--- /dev/null
+++ b/board/nocturne_fp/board_ro.c
@@ -0,0 +1,77 @@
+/* Copyright 2017 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+/* Meowth Fingerprint MCU configuration */
+
+#include "common.h"
+#include "hooks.h"
+#include "registers.h"
+#include "spi.h"
+#include "system.h"
+#include "task.h"
+
+#ifndef SECTION_IS_RO
+#error "This file should only be built for RO."
+#endif
+
+
+/**
+ * Disable restricted commands when the system is locked.
+ *
+ * @see console.h system.c
+ */
+int console_is_restricted(void)
+{
+	return system_is_locked();
+}
+
+#include "gpio_list.h"
+
+static void ap_deferred(void)
+{
+	/*
+	 * Behavior:
+	 * AP Active  (ex. Intel S0):   SLP_L is 1
+	 * AP Suspend (ex. Intel S0ix): SLP_L is 0
+	 * The alternative SLP_ALT_L should be pulled high at all the times.
+	 *
+	 * Legacy Intel behavior:
+	 * in S3:   SLP_ALT_L is 0 and SLP_L is X.
+	 * in S0ix: SLP_ALT_L is X and SLP_L is 0.
+	 * in S0:   SLP_ALT_L is 1 and SLP_L is 1.
+	 * in S5/G3, the FP MCU should not be running.
+	 */
+	int running = gpio_get_level(GPIO_SLP_ALT_L) &&
+		      gpio_get_level(GPIO_SLP_L);
+
+	if (running) { /* AP is S0 */
+		disable_sleep(SLEEP_MASK_AP_RUN);
+		hook_notify(HOOK_CHIPSET_RESUME);
+	} else { /* AP is suspend/S0ix/S3 */
+		hook_notify(HOOK_CHIPSET_SUSPEND);
+		enable_sleep(SLEEP_MASK_AP_RUN);
+	}
+}
+DECLARE_DEFERRED(ap_deferred);
+
+/* PCH power state changes */
+void slp_event(enum gpio_signal signal)
+{
+	hook_call_deferred(&ap_deferred_data, 0);
+}
+
+void board_init(void)
+{
+	/* Enable interrupt on PCH power signals */
+	gpio_enable_interrupt(GPIO_SLP_ALT_L);
+	gpio_enable_interrupt(GPIO_SLP_L);
+
+	/*
+	 * Enable the SPI slave interface if the PCH is up.
+	 * Do not use hook_call_deferred(), because ap_deferred() will be
+	 * called after tasks with priority higher than HOOK task (very late).
+	 */
+	ap_deferred();
+}
+DECLARE_HOOK(HOOK_INIT, board_init, HOOK_PRIO_DEFAULT);
diff --git a/board/nocturne_fp/board_rw.c b/board/nocturne_fp/board_rw.c
index 657f155a4a..0a7b38b97d 100644
--- a/board/nocturne_fp/board_rw.c
+++ b/board/nocturne_fp/board_rw.c
@@ -19,6 +19,18 @@
 #error "This file should only be built for RW."
 #endif
 
+/**
+ * Disable restricted commands when the system is locked.
+ *
+ * @see console.h system.c
+ */
+int console_is_restricted(void)
+{
+	return system_is_locked();
+}
+
+#include "gpio_list.h"
+
 /* SPI devices */
 struct spi_device_t spi_devices[] = {
 	/* Fingerprint sensor (SCLK at 4Mhz) */
@@ -84,7 +96,7 @@ static void spi_configure(enum fp_sensor_spi_select spi_select)
 	spi_enable(&spi_devices[0], 1);
 }
 
-void board_init_rw(void)
+void board_init(void)
 {
 	enum fp_sensor_spi_select spi_select = get_fp_sensor_spi_select();
 
@@ -111,6 +123,7 @@ void board_init_rw(void)
 	/* Enable interrupt on PCH power signals */
 	gpio_enable_interrupt(gpio_slp_alt_l);
 	gpio_enable_interrupt(GPIO_SLP_L);
+
 	/*
 	 * Enable the SPI slave interface if the PCH is up.
 	 * Do not use hook_call_deferred(), because ap_deferred() will be
@@ -118,3 +131,4 @@ void board_init_rw(void)
 	 */
 	ap_deferred();
 }
+DECLARE_HOOK(HOOK_INIT, board_init, HOOK_PRIO_DEFAULT);
diff --git a/board/nocturne_fp/board_rw.h b/board/nocturne_fp/board_rw.h
index 29e304f115..6ef7cc29b4 100644
--- a/board/nocturne_fp/board_rw.h
+++ b/board/nocturne_fp/board_rw.h
@@ -7,11 +7,8 @@
 #define __CROS_EC_BOARD_NOCTURNE_FP_BOARD_RW_H
 
 void fps_event(enum gpio_signal signal);
-void slp_event(enum gpio_signal signal);
 
 /* Defined in ro_workarounds.c */
 void wp_event(enum gpio_signal signal);
 
-void board_init_rw(void);
-
 #endif /* __CROS_EC_BOARD_NOCTURNE_FP_BOARD_RW_H */
diff --git a/board/nocturne_fp/build.mk b/board/nocturne_fp/build.mk
index f6fd9fe3d9..2091acc101 100644
--- a/board/nocturne_fp/build.mk
+++ b/board/nocturne_fp/build.mk
@@ -9,8 +9,12 @@ CHIP:=stm32
 CHIP_FAMILY:=stm32h7
 CHIP_VARIANT:=stm32h7x3
 
+# Don't forget that the board build.mk is included more than once to allow
+# conditional variables to be realized. This means that we need to redefine all
+# variable or the "+=" lines will compound.
+board-y=
 board-rw=ro_workarounds.o board_rw.o
-board-y=board.o
+board-ro=board_ro.o
 # If we're mocking the sensor detection for testing (so we can test
 # sensor/transport permutations in the unit tests), don't build the real sensor
 # detection.
diff --git a/board/nocturne_fp/gpio.inc b/board/nocturne_fp/gpio.inc
index 7e90ef0da4..ff94e4f8f7 100644
--- a/board/nocturne_fp/gpio.inc
+++ b/board/nocturne_fp/gpio.inc
@@ -5,6 +5,9 @@
  */
 
 /* Interrupts */
+GPIO_INT(SLP_L,           PIN(D,13), GPIO_INT_BOTH, slp_event)
+GPIO_INT(SLP_ALT_L,       PIN(A,11), GPIO_INT_BOTH, slp_event)
+GPIO_INT(SLP_ALT_DEV_L,   PIN(D,14), GPIO_INT_BOTH, slp_event)
 GPIO_INT(SPI1_NSS,        PIN(A, 4), GPIO_INPUT, spi_event)
 
 /* Inputs */
diff --git a/board/nocturne_fp/gpio_rw.inc b/board/nocturne_fp/gpio_rw.inc
index 65036abe14..088ce22f32 100644
--- a/board/nocturne_fp/gpio_rw.inc
+++ b/board/nocturne_fp/gpio_rw.inc
@@ -10,9 +10,6 @@
 
 /* Interrupts */
 GPIO_INT(FPS_INT,         PIN(A, 0), GPIO_INT_RISING, fps_event)
-GPIO_INT(SLP_L,           PIN(D,13), GPIO_INT_BOTH, slp_event)
-GPIO_INT(SLP_ALT_L,       PIN(A,11), GPIO_INT_BOTH, slp_event)
-GPIO_INT(SLP_ALT_DEV_L,   PIN(D,14), GPIO_INT_BOTH, slp_event)
 
 #ifdef APPLY_RESET_LOOP_FIX
 GPIO_INT(WP,              PIN(B, 7), GPIO_INT_BOTH, wp_event)