Here is a list of all modules:

[detail level 1234]

▼CM3 Defines	Defined Constants and Types for Cortex M3 core features
Debugging	Macros and functions to aid in debugging
▼Cortex Core Defines	libopencm3 Defined Constants and Types for the Cortex Core
Cortex Core Atomic support Defines	Atomic operation support
Cortex-M Data Watch and Trace unit.	System Control Space (SCS) => Data Watchpoint and Trace (DWT)
Cortex-M Flash Patch and Breakpoint (FPB) unit
Cortex-M Instrumentation Trace Macrocell (ITM)
▼Cortex-M MPU Defines	libopencm3 Cortex Memory Protection Unit
MPU Registers
MPU TYPE register fields	The MPU_TYPE register is always available, even if the MPU is not implemented
MPU CTRL register fields	Defines for the Control Register
MPU RNR register fields	Defines for the Region Number Register
MPU RBAR register fields	Defines for the Region Base Address Register
▼MPU RASR register fields	Defines for the Region Attribute and Size Register
MPU RASR Attributes	Not all attributes are available on v6m
▼Cortex-M NVIC Defines	libopencm3 Cortex Nested Vectored Interrupt Controller
NVIC Registers
Cortex M0/M3/M4 System Interrupts	IRQ numbers -3 and -6 to -9 are reserved
User interrupts for EFM32 Happy Gecko series
▼Cortex-M System Control Block	The System Control Block is a section of the System Control Space
SCB Registers
SCB_CPUID Values
SCB_ICSR Values
SCB_VTOR Values
SCB_AICR Values
SCB_SCR Values
SCB_CCR Values
▼Cortex-M System Control Space	The System Control Space (SCS) is a memory-mapped 4KB address space that provides 32-bit registers for configuration, status reporting and control
SCS Registers
▼Cortex-M SysTick Defines	libopencm3 Defined Constants and Types for the Cortex SysTick
▼STK_CSR Values
Clock source selection
STK_RVR Values
STK_CALIB Values
Cortex-M Trace Port Interface Unit (TPIU)
▼Cortex Core Peripheral APIs	APIs for Cortex Core peripherals
DWT	libopencm3 Cortex-M Data Watchpoint and Trace unit
NVIC	libopencm3 Cortex Nested Vectored Interrupt Controller
SCB	libopencm3 Cortex-M System Control Block
SysTick	libopencm3 Cortex System Tick Timer
Coresight Registers	CoreSight Lock Status Registers and Lock Access Registers are documented for the DWT, ITM, FPB and TPIU peripherals
EFM32 HappyGecko	Libraries for Energy Micro EFM32 Happy Gecko series
▼Peripheral APIs	APIs for device peripherals
CMU peripheral API
GPIO peripheral API
TIMER peripheral API
USB peripheral API	USB Peripheral for Happy Gecko
▼EFM32 Happy Gecko Defines	Defined Constants and Types for the Energy Micro EFM32 Happy Gecko series
CMU Defines	Defined Constants and Types for the EFM32HG Clock Management Unit
GPIO Defines	Defined Constants and Types for the EFM32HG GPIO module
▼TIMER Defines	Defined Constants and Types for the TIMER module
Timer Channel Number
USB Defines	Defined Constants and Types for the USB module
WDOG Defines	Defined Constants and Types for the Watchdog module
User interrupt service routines (ISR) prototypes for EFM32 Happy Gecko series
USB Audio Type Definitions	Defined Constants and Types for the USB Audio Type Definitions
USB CDC Type Definitions	Defined Constants and Types for the USB CDC Type Definitions
USB HID Type Definitions	Defined Constants and Types for the USB HID Type Definitions
USB MSC Type Definitions	Defined Constants and Types for the USB MSC Type Definitions
USB Drivers	Defined Constants and Types for the USB Drivers
USB Standard Structure Definitions	Defined Constants and Types for the USB Standard Structure Definitions
User interrupt service routines (ISR) defaults for EFM32 Happy Gecko series
Generic USB Drivers	Generic USB Drivers
Generic USB Control Requests	Generic USB Control Requests
Generic USB Standard Request Interface	Generic USB Standard Request Interface
Usb_msc