zephyr: Check if BB retimers are configured properly

Check at compile time, that all BB retimers on the same USB-C port have
the same reset and LS_EN pin configuration. This is required because of
single entry in bb_controls array for each USB-C port.

BUG=none
TEST=zmake build -a
TEST=./twister -T zephyr/test
BRANCH=none

Signed-off-by: Tomasz Michalec <tm@semihalf.com>
Change-Id: I46b04385df99467b1ff1d4a484be5bb016c8a2d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3748786
Reviewed-by: Keith Short <keithshort@chromium.org>
Commit-Queue: Tomasz Michalec <tmichalec@google.com>
Tested-by: Tomasz Michalec <tmichalec@google.com>

2 files changed, 73 insertions, 8 deletions

diff --git a/zephyr/shim/include/usbc/bb_retimer_usb_mux.h b/zephyr/shim/include/usbc/bb_retimer_usb_mux.h
index aa15c9f5f2..64e1e2693d 100644
--- a/zephyr/shim/include/usbc/bb_retimer_usb_mux.h
+++ b/zephyr/shim/include/usbc/bb_retimer_usb_mux.h
@@ -19,14 +19,27 @@
 			.i2c_addr_flags = DT_REG_ADDR(mux_id), \
 	}
 
-#define BB_RETIMER_CONTROLS_CONFIG(mux_id)                            \
-	{                                                             \
-		.retimer_rst_gpio =                                   \
-			GPIO_SIGNAL(DT_PHANDLE(mux_id, reset_pin)),   \
-		.usb_ls_en_gpio = COND_CODE_1(                        \
-			DT_NODE_HAS_PROP(mux_id, ls_en_pin),          \
-			(GPIO_SIGNAL(DT_PHANDLE(mux_id, ls_en_pin))), \
-			(GPIO_UNIMPLEMENTED)),                        \
+/**
+ * @brief Get reset gpio for @p mux_id retimer
+ *
+ * @param mux_id BB retimer DTS node
+ */
+#define BB_RETIMER_RESET_GPIO(mux_id) GPIO_SIGNAL(DT_PHANDLE(mux_id, reset_pin))
+
+/**
+ * @brief Get LS_EN gpio for @p mux_id retimer
+ *
+ * @param mux_id BB retimer DTS node
+ */
+#define BB_RETIMER_LS_EN_GPIO(mux_id)                             \
+	COND_CODE_1(DT_NODE_HAS_PROP(mux_id, ls_en_pin),          \
+		    (GPIO_SIGNAL(DT_PHANDLE(mux_id, ls_en_pin))), \
+		    (GPIO_UNIMPLEMENTED))
+
+#define BB_RETIMER_CONTROLS_CONFIG(mux_id)                         \
+	{                                                          \
+		.retimer_rst_gpio = BB_RETIMER_RESET_GPIO(mux_id), \
+		.usb_ls_en_gpio = BB_RETIMER_LS_EN_GPIO(mux_id),   \
 	}
 
 /**
@@ -44,4 +57,53 @@
 	DT_FOREACH_STATUS_OKAY(BB_RETIMER_USB_MUX_COMPAT, \
 			       USB_MUX_BB_RETIMER_CONTROL_ARRAY)
 
+/**
+ * @brief Check if BB retimers @p id_1 and @p id_2 has matching configuration
+ *        Configuration match if reset and ls_en pins are the same for muxes
+ *        which are on the same USB-C port.
+ *
+ * @param id_1 First BB retimer DTS node
+ * @param id_2 Second BB retimer DTS node
+ */
+#define BB_RETIMER_CHECK_PAIR(id_1, id_2)                                      \
+	BUILD_ASSERT(USB_MUX_PORT(id_1) != USB_MUX_PORT(id_2) ||               \
+			     (BB_RETIMER_RESET_GPIO(id_1) ==                   \
+				      BB_RETIMER_RESET_GPIO(id_2) &&           \
+			      BB_RETIMER_LS_EN_GPIO(id_1) ==                   \
+				      BB_RETIMER_LS_EN_GPIO(id_2)),            \
+		     "BB retimers " #id_1 " and " #id_2 " have different pin " \
+		     "configuration and same USB-C port")
+
+/**
+ * @brief Check if BB retimers with @p inst instance number has matching
+ *        configuration with muxes of higher instance number on @p bb_list list.
+ *        Configuration match if reset and ls_en pins are the same for muxes
+ *        which are on the same USB-C port.
+ *
+ * @param inst Instance number of BB retimer mux
+ * @param bb_list List of BB retimers in instance number order
+ */
+#define BB_RETIMER_CHECK_INSTANCE_WITH_LIST(inst, bb_list)           \
+	FOR_EACH_FIXED_ARG(BB_RETIMER_CHECK_PAIR, (;),               \
+			   DT_INST(inst, BB_RETIMER_USB_MUX_COMPAT), \
+			   GET_ARGS_LESS_N(inst, __DEBRACKET bb_list))
+
+/**
+ * @brief Check if BB retimers on the @p bb_list list have matching
+ *        configurations (i.e. reset and ls_en pins are the same for muxes
+ *        which are on the same USB-C port). This check is required, because
+ *        USB_MUX_ENABLE_ALTERNATE() doesn't update bb_control[] array, so all
+ *        BB retimers needs to use the same GPIO pins.
+ *
+ * @param bb_list List of BB retimers in instance number order
+ */
+#define BB_RETIMER_CHECK_SAME_CONTROLS(bb_list)                     \
+	LISTIFY(DT_NUM_INST_STATUS_OKAY(BB_RETIMER_USB_MUX_COMPAT), \
+		BB_RETIMER_CHECK_INSTANCE_WITH_LIST, (;), bb_list);
+
+/** List of all BB retimers in DTS in instance number order */
+#define BB_RETIMER_INSTANCES_LIST                                             \
+	(LISTIFY(DT_NUM_INST_STATUS_OKAY(BB_RETIMER_USB_MUX_COMPAT), DT_INST, \
+		 (, ), BB_RETIMER_USB_MUX_COMPAT))
+
 #endif /* __ZEPHYR_SHIM_BB_RETIMER_USB_MUX_H */
diff --git a/zephyr/shim/src/usb_muxes.c b/zephyr/shim/src/usb_muxes.c
index d9f14d0c67..71dc66f76a 100644
--- a/zephyr/shim/src/usb_muxes.c
+++ b/zephyr/shim/src/usb_muxes.c
@@ -99,6 +99,9 @@ USB_MUX_FOREACH_MUX(USB_MUX_DEFINE)
 /* Create bb_controls only if BB or HB retimer driver is enabled */
 #if defined(CONFIG_PLATFORM_EC_USBC_RETIMER_INTEL_BB) || \
 	defined(CONFIG_PLATFORM_EC_USBC_RETIMER_INTEL_HB)
+
+BB_RETIMER_CHECK_SAME_CONTROLS(BB_RETIMER_INSTANCES_LIST)
+
 /**
  * @brief bb_controls array should be constant only if configuration cannot
  *        change in runtime