zephyr: shim: add single charge task support

Add an option to run the charger code in a single task.

This is enabled by default in Zephyr builds, but explicitly disabled for
a couple of platforms that currently have task dependent board code.

Should be enough to start testing the configuration, will work on
handling the remaining boards (corsola and nissa) later.

BRANCH=none
BUG=b:226411332
TEST=make buildall
TEST=zmake testall
TEST=cq dry run
TEST=run on Brya, connect/disconnect usb devices

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
Change-Id: I75a63f7b0a9545e6c824114de7f81b71924e0789
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3663748
Reviewed-by: Keith Short <keithshort@chromium.org>
Reviewed-by: Diana Z <dzigterman@chromium.org>
Reviewed-by: Aaron Massey <aaronmassey@google.com>

9 files changed, 109 insertions, 12 deletions

diff --git a/common/usb_charger.c b/common/usb_charger.c
index 5387dba594..d0b6dd3ca1 100644
--- a/common/usb_charger.c
+++ b/common/usb_charger.c
@@ -26,6 +26,26 @@
 #include "usbc_ppc.h"
 #include "util.h"
 
+#ifdef CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK
+
+/* Hold the event bits for all ports, 1 byte per port. */
+static atomic_t usb_charger_port_events;
+
+/* Convert event bits for port so it can be stored in a 32 bit value. */
+#define PORT_EVENT_PACK(port, event) ((event & 0xff) << (8 * port))
+
+/* Extract the event bits for port from a 32 bit value. */
+#define PORT_EVENT_UNPACK(port, event_packed) \
+	((event_packed >> (8 * port)) & 0xff)
+
+/* Ensure port event bits are valid. */
+BUILD_ASSERT(BIT(0) == TASK_EVENT_CUSTOM_BIT(0));
+BUILD_ASSERT(BIT(1) == TASK_EVENT_CUSTOM_BIT(1));
+BUILD_ASSERT(BIT(2) == TASK_EVENT_CUSTOM_BIT(2));
+BUILD_ASSERT(BIT(3) == TASK_EVENT_CUSTOM_BIT(3));
+
+#endif /* CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK */
+
 static void update_vbus_supplier(int port, int vbus_level)
 {
 	struct charge_port_info charge = {0};
@@ -73,7 +93,8 @@ void usb_charger_vbus_change(int port, int vbus_level)
 	/* Update VBUS supplier and signal VBUS change to USB_CHG task */
 	update_vbus_supplier(port, vbus_level);
 
-#ifdef HAS_TASK_USB_CHG_P0
+#if defined(HAS_TASK_USB_CHG_P0) || \
+	defined(CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK)
 	/* USB Charger task(s) */
 	usb_charger_task_set_event(port, USB_CHG_EVENT_VBUS);
 
@@ -116,9 +137,14 @@ void usb_charger_reset_charge(int port)
 
 }
 
-void usb_charger_task_set_event(int port, uint32_t event)
+void usb_charger_task_set_event(int port, uint8_t event)
 {
+#ifdef CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK
+	atomic_or(&usb_charger_port_events, PORT_EVENT_PACK(port, event));
+	task_set_event(TASK_ID_USB_CHG, BIT(port));
+#else
 	task_set_event(USB_CHG_PORT_TO_TASK_ID(port), event);
+#endif
 }
 
 static void usb_charger_init(void)
@@ -132,6 +158,47 @@ static void usb_charger_init(void)
 }
 DECLARE_HOOK(HOOK_INIT, usb_charger_init, HOOK_PRIO_POST_CHARGE_MANAGER);
 
+#ifdef CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK
+
+void usb_charger_task_shared(void *u)
+{
+	int port;
+	uint32_t evt;
+	uint32_t port_evt;
+	struct bc12_config *bc12_port;
+
+	for (port = 0; port < board_get_usb_pd_port_count(); port++) {
+		bc12_port = &bc12_ports[port];
+
+		ASSERT(bc12_port->drv->usb_charger_task_init);
+		ASSERT(bc12_port->drv->usb_charger_task_event);
+
+		bc12_port->drv->usb_charger_task_init(port);
+	}
+
+	while (1) {
+		evt = task_wait_event(-1);
+
+		for (port = 0; port < board_get_usb_pd_port_count(); port++) {
+			if (!(evt & BIT(port))) {
+				continue;
+			}
+
+			port_evt = PORT_EVENT_UNPACK(
+					port,
+					atomic_get(&usb_charger_port_events));
+			atomic_and(&usb_charger_port_events,
+				   ~PORT_EVENT_PACK(port, port_evt));
+
+			bc12_port = &bc12_ports[port];
+
+			bc12_port->drv->usb_charger_task_event(port, port_evt);
+		}
+	}
+}
+
+#else /* CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK */
+
 void usb_charger_task(void *u)
 {
 	int port = TASK_ID_TO_USB_CHG_PORT(task_get_current());
@@ -157,3 +224,5 @@ void usb_charger_task(void *u)
 		bc12_port->drv->usb_charger_task_event(port, evt);
 	}
 }
+
+#endif /* CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK */
diff --git a/include/charge_manager.h b/include/charge_manager.h
index 2cded28295..b6d3c235bf 100644
--- a/include/charge_manager.h
+++ b/include/charge_manager.h
@@ -19,7 +19,8 @@
 
 /* Only track BC1.2 charge current if we support BC1.2 charging */
 #if defined(HAS_TASK_USB_CHG) || defined(HAS_TASK_USB_CHG_P0) || \
-defined(TEST_BUILD)
+	defined(CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK) || \
+	defined(TEST_BUILD)
 #define CHARGE_MANAGER_BC12
 #endif
 
diff --git a/include/usb_charge.h b/include/usb_charge.h
index ec7a655256..135258c7cf 100644
--- a/include/usb_charge.h
+++ b/include/usb_charge.h
@@ -55,13 +55,23 @@ extern const int usb_port_enable[USB_PORT_ENABLE_COUNT];
 int usb_charge_set_mode(int usb_port_id, enum usb_charge_mode mode,
 			enum usb_suspend_charge inhibit_charge);
 
-#define USB_CHG_EVENT_BC12	TASK_EVENT_CUSTOM_BIT(0)
-#define USB_CHG_EVENT_VBUS	TASK_EVENT_CUSTOM_BIT(1)
-#define USB_CHG_EVENT_INTR	TASK_EVENT_CUSTOM_BIT(2)
-#define USB_CHG_EVENT_DR_UFP	TASK_EVENT_CUSTOM_BIT(3)
-#define USB_CHG_EVENT_DR_DFP	TASK_EVENT_CUSTOM_BIT(4)
-#define USB_CHG_EVENT_CC_OPEN	TASK_EVENT_CUSTOM_BIT(5)
-#define USB_CHG_EVENT_MUX	TASK_EVENT_CUSTOM_BIT(6)
+#ifdef CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK
+/*
+ * In single task mode we pack the event bits for up to 4 ports in a 32 bit
+ * atomic, make sure we don't define more than 8 event bits per port.
+ */
+#define USB_CHARGER_EVENT_BIT(x) BUILD_CHECK_INLINE(BIT(x), BIT(x) & 0xff)
+#else
+#define USB_CHARGER_EVENT_BIT(x) TASK_EVENT_CUSTOM_BIT(x)
+#endif
+
+#define USB_CHG_EVENT_BC12	USB_CHARGER_EVENT_BIT(0)
+#define USB_CHG_EVENT_VBUS	USB_CHARGER_EVENT_BIT(1)
+#define USB_CHG_EVENT_INTR	USB_CHARGER_EVENT_BIT(2)
+#define USB_CHG_EVENT_DR_UFP	USB_CHARGER_EVENT_BIT(3)
+#define USB_CHG_EVENT_DR_DFP	USB_CHARGER_EVENT_BIT(4)
+#define USB_CHG_EVENT_CC_OPEN	USB_CHARGER_EVENT_BIT(5)
+#define USB_CHG_EVENT_MUX	USB_CHARGER_EVENT_BIT(6)
 
 /*
  * Define USB_CHG_PORT_TO_TASK_ID() and TASK_ID_TO_USB_CHG_PORT() macros to
@@ -174,7 +184,7 @@ static inline int usb_charger_ramp_max(int port, int supplier, int sup_curr)
  * @param port port number
  * @param event event bits (USB_CHG_EVENT_*)
  */
-void usb_charger_task_set_event(int port, uint32_t event);
+void usb_charger_task_set_event(int port, uint8_t event);
 
 /**
  * Reset available BC 1.2 chargers on all ports
diff --git a/zephyr/Kconfig.usb_charger b/zephyr/Kconfig.usb_charger
index 1510e981d1..dd167dddae 100644
--- a/zephyr/Kconfig.usb_charger
+++ b/zephyr/Kconfig.usb_charger
@@ -15,6 +15,12 @@ config PLATFORM_EC_USB_CHARGER
 
 if PLATFORM_EC_USB_CHARGER
 
+config PLATFORM_EC_USB_CHARGER_SINGLE_TASK
+	bool "Run all charger code in a single task"
+	default y
+	help
+	  Run all USB charger code in a single task rather than a task per port.
+
 config PLATFORM_EC_BC12_DETECT_DATA_ROLE_TRIGGER
 	bool
 	help
diff --git a/zephyr/app/ec/Kconfig b/zephyr/app/ec/Kconfig
index b8d46f8678..ebdeebfdf2 100644
--- a/zephyr/app/ec/Kconfig
+++ b/zephyr/app/ec/Kconfig
@@ -24,7 +24,7 @@ orsource "chip/$(ARCH)/*/Kconfig.*"
 # Override the maximum number of preemptive priority levels.
 #
 config NUM_PREEMPT_PRIORITIES
-	default 25
+	default 26
 
 #
 # In Zephyr, the default system workqueue thread priority level is the lowest
diff --git a/zephyr/projects/corsola/prj.conf b/zephyr/projects/corsola/prj.conf
index 2b087fa310..b9d07a7227 100644
--- a/zephyr/projects/corsola/prj.conf
+++ b/zephyr/projects/corsola/prj.conf
@@ -26,6 +26,8 @@ CONFIG_PLATFORM_EC_VBOOT_EFS2=y
 # USB
 CONFIG_PLATFORM_EC_USB_PD_TBT_COMPAT_MODE=n
 CONFIG_PLATFORM_EC_USB_PD_USB4=n
+# TODO(b/226411332): fix single task USB_CHG for Corsola
+CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK=n
 
 # Power Seq
 CONFIG_PLATFORM_EC_POWERSEQ_HOST_SLEEP=y
diff --git a/zephyr/projects/nissa/prj.conf b/zephyr/projects/nissa/prj.conf
index 828fccd8be..621355bf6a 100644
--- a/zephyr/projects/nissa/prj.conf
+++ b/zephyr/projects/nissa/prj.conf
@@ -122,6 +122,8 @@ CONFIG_PLATFORM_EC_USB_MUX_VIRTUAL=y
 # ADL integrated muxes are slow: unblock PD
 CONFIG_PLATFORM_EC_USB_MUX_TASK=y
 CONFIG_PLATFORM_EC_BC12_DETECT_PI3USB9201=y
+# TODO(b/226411332): fix single task USB_CHG for Nissa
+CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK=n
 
 # USB-C TCPC and PPC standard options
 CONFIG_PLATFORM_EC_USB_PD_TCPC_LOW_POWER=y
diff --git a/zephyr/shim/include/config_chip.h b/zephyr/shim/include/config_chip.h
index a811b68ccc..d3924e644d 100644
--- a/zephyr/shim/include/config_chip.h
+++ b/zephyr/shim/include/config_chip.h
@@ -1447,6 +1447,7 @@ extern struct jump_data mock_jump_data;
 #endif /* CONFIG_PLATFORM_EC_USB_POWER_DELIVERY */
 
 #ifdef CONFIG_PLATFORM_EC_USB_CHARGER
+#ifndef CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK
 #define HAS_TASK_USB_CHG_P0 1
 
 #if CONFIG_USB_PD_PORT_MAX_COUNT > 1
@@ -1461,6 +1462,7 @@ extern struct jump_data mock_jump_data;
 #define HAS_TASK_USB_CHG_P3 1
 #endif /* CONFIG_USB_PD_PORT_MAX_COUNT > 3 */
 
+#endif /* !PLATFORM_EC_USB_CHARGER_SINGLE_TASK */
 #endif /* CONFIG_PLATFORM_EC_USB_CHARGER */
 
 #undef CONFIG_USB_PD_ITE_ACTIVE_PORT_COUNT
diff --git a/zephyr/shim/include/shimmed_task_id.h b/zephyr/shim/include/shimmed_task_id.h
index 88298a401a..31df4daece 100644
--- a/zephyr/shim/include/shimmed_task_id.h
+++ b/zephyr/shim/include/shimmed_task_id.h
@@ -28,6 +28,7 @@ enum {
 	EC_TASK_PRIO_LOWEST = 0,
 	EC_SYSWORKQ_PRIO = EC_TASK_PRIO_LOWEST,
 	EC_TASK_CHG_RAMP_PRIO,
+	EC_TASK_USB_CHG_PRIO,
 	EC_TASK_USB_CHG_P0_PRIO,
 	EC_TASK_USB_CHG_P1_PRIO,
 	EC_TASK_USB_CHG_P2_PRIO,
@@ -68,6 +69,10 @@ enum {
 		     (CROS_EC_TASK(CHG_RAMP, chg_ramp_task, 0,            \
 				   CONFIG_TASK_CHG_RAMP_STACK_SIZE,       \
 				   EC_TASK_CHG_RAMP_PRIO)), ())           \
+	COND_CODE_1(CONFIG_PLATFORM_EC_USB_CHARGER_SINGLE_TASK,           \
+		     (CROS_EC_TASK(USB_CHG, usb_charger_task_shared, 0,   \
+				   CONFIG_TASK_USB_CHG_STACK_SIZE,        \
+				   EC_TASK_USB_CHG_PRIO)), ())            \
 	COND_CODE_1(HAS_TASK_USB_CHG_P0,                                  \
 		     (CROS_EC_TASK(USB_CHG_P0, usb_charger_task, 0,       \
 				   CONFIG_TASK_USB_CHG_STACK_SIZE,        \