TIM internal peripheral

Applicable for

STM32MP13x lines, STM32MP15x lines, Unknown MPU

---

1. Article purpose

The purpose of this article is to:

• briefly introduce the TIM peripheral and its main features,
• indicate the peripheral instances assignment at boot time and their assignment at runtime (including whether instances can be allocated to secure contexts),
• list the software frameworks and drivers managing the peripheral,
• explain how to configure the peripheral.

2. Peripheral overview

The TIM peripheral is a multi-channel timer unit, available in various configurations, depending on the instance used. There are basically following categories: advanced-control timers, general-purpose timers and basic timers.

The TIM can provide: PWM with complementary output and dead-time insertion, break detection, input capture, quadrature encoder interface (typically used for rotary encoders), trigger source for other internal peripherals like: ADC, DFSDM. The full list can be found in Peripherals Interconnect matrix in the reference manual.

The TIM peripheral is available in different configurations, depending on the selected instance :

• TIM1 and TIM8 are advanced-control timers, with 6 independent channels.
• TIM2, TIM3, TIM4 and TIM5 are general-purpose timers, with 4 independent channels.
• TIM12, TIM13 and TIM14 are general-purpose timers, with 2 (TIM12) or 1 (TIM13 and TIM14) independent channels.
• TIM15, TIM16 and TIM17 are also general-purpose timers, with 2 (TIM15) or 1 (TIM16 and TIM17) independent channels. Compare to TIM12, TIM13 and TIM14, this configuration brings some features that are very useful for motor control (like break function, DMA burst mode control, complementary output with dead-time insertion, ...)
• TIM6 and TIM7 are basic timers

On STM32MP25x lines , additional instances are available:

• TIM20 is an advanced-control timer, with 6 independent channels.
• TIM10 and TIM11 are general-purpose timers with 1 channel.

Refer to the STM32 MPU reference manuals for the complete list of features, and to the software frameworks and drivers, introduced below, to see which features are implemented.

3. Peripheral usage

This chapter is applicable in the scope of the OpenSTLinux BSP running on the Arm^® Cortex^®-A processor(s), and the STM32CubeMPU Package running on the Arm^® Cortex^®-M processor.

3.1. Boot time assignment

3.1.1. On STM32MP13x lines 

Click on to expand or collapse the legend...

Check boxes illustrate the possible peripheral allocations supported by STM32 MPU Embedded Software:

• ☐ means that the peripheral can be assigned to the given boot time context.
• ☑ means that the peripheral is assigned by default to the given boot time context and that the peripheral is mandatory for the STM32 MPU Embedded Software distribution.
• ⬚ means that the peripheral can be assigned to the given boot time context, but this configuration is not supported in STM32 MPU Embedded Software distribution.
• ✓ is used for system peripherals that cannot be unchecked because they are hardware connected in the device.

The present chapter describes STMicroelectronics recommendations or choice of implementation. Additional possibilities might be described in STM32 MPU reference manuals.

Domain	Peripheral	Boot time allocation				Comment
		Instance	Cortex-A7 secure (ROM code)	Cortex-A7 secure (TF-A BL2)	Cortex-A7 non-secure (U-Boot)
Core/Timers	TIM	TIMx (x = 1 to 8, APB2 group)			⬚
		TIMx (x = 2 to 7, APB1 group)			⬚
		TIMx (x = 12 to 17, APB6 group)		⬚	⬚

3.1.2. On STM32MP15x lines 

Click on to expand or collapse the legend...

Check boxes illustrate the possible peripheral allocations supported by STM32 MPU Embedded Software:

• ☐ means that the peripheral can be assigned to the given boot time context.
• ☑ means that the peripheral is assigned by default to the given boot time context and that the peripheral is mandatory for the STM32 MPU Embedded Software distribution.
• ⬚ means that the peripheral can be assigned to the given boot time context, but this configuration is not supported in STM32 MPU Embedded Software distribution.
• ✓ is used for system peripherals that cannot be unchecked because they are hardware connected in the device.

The present chapter describes STMicroelectronics recommendations or choice of implementation. Additional possibilities might be described in STM32 MPU reference manuals.

Domain	Peripheral	Boot time allocation				Comment
		Instance	Cortex-A7 secure (ROM code)	Cortex-A7 secure (TF-A BL2)	Cortex-A7 non-secure (U-Boot)
Core/Timers	TIM	TIMx (x = 2 to 7, 12, 13, 14. APB1 group)			⬚
		TIMx (x = 1, 8, 15, 16, 17. APB2 group)			⬚

3.1.3. On STM32MP25x lines 

STM32MP2 internal peripherals assignment table template

| rowspan="1" | Core/Timers | rowspan="1" | TIM | TIMx (x = 1 to 8, 10 to 17, 20) | | ⬚ | ⬚ | |-

|}

3.2. Runtime assignment

3.2.1. On STM32MP13x lines 

TIM12 and/or TIM15 can be allocated to the Arm^® Cortex^®-A7 secure core to be controlled in the secure monitor (OP-TEE).
TIM13, TIM14, TIM16 and TIM17 can also be allocated to the Arm^® Cortex^®-A7 secure context, but it is not supported yet by OpenSTLinux.

Information

RCC owns one prescaler per TIM group corresponding to APB1, APB2 and APB6 buses: TIMG1PRE, TIMG2PRE and TIMG3PRE, respectively. TIMG3PRE is securable in RCC. The allocation to Cortex-A7 contexts should ideally be done on a per group basis to get independent clocking setup on each side, this is why the TIM instances groups are shown in the summary table below.

Click on to expand or collapse the legend...

STM32MP13 internal peripherals

Check boxes illustrate the possible peripheral allocations supported by STM32 MPU Embedded Software:

• ☐ means that the peripheral can be assigned to the given runtime context.
• ☑ means that the peripheral is assigned by default to the given runtime context and that the peripheral is mandatory for the STM32 MPU Embedded Software distribution.
• ⬚ means that the peripheral can be assigned to the given runtime context, but this configuration is not supported in STM32 MPU Embedded Software distribution.
• ✓ is used for system peripherals that cannot be unchecked because they are hardware connected in the device.

Refer to How to assign an internal peripheral to an execution context for more information on how to assign peripherals manually or via STM32CubeMX.
The present chapter describes STMicroelectronics recommendations or choice of implementation. Additional possibilities might be described in STM32MP13 reference manuals.

Domain	Peripheral	Runtime allocation			Comment
		Instance	Cortex-A7 secure (OP-TEE)	Cortex-A7 non-secure (Linux)
Core/Timers	TIM	TIM1 (APB2 group)		☐
		TIM2 (APB1 group)		☐
		TIM3 (APB1 group)		☐
		TIM4 (APB1 group)		☐
		TIM5 (APB1 group)		☐
		TIM6 (APB1 group)		☐
		TIM7 (APB1 group)		☐
		TIM8 (APB2 group)		☐
		TIM12 (APB6 group)	☐	☐	Assignment (single choice) TIM12 or TIM15 can be used for HSI/CSI calibration
		TIM13 (APB6 group)	☐	☐	Assignment (single choice)
		TIM14 (APB6 group)	☐	☐	Assignment (single choice)
		TIM15 (APB6 group)	☐	☐	Assignment (single choice) TIM12 or TIM15 can be used for HSI/CSI calibration
		TIM16 (APB6 group)	☐	☐	Assignment (single choice)
		TIM17 (APB6 group)	☐	☐	Assignment (single choice)

3.2.2. On STM32MP15x lines 

TIM12 and/or TIM15 can be allocated to the Arm^® Cortex^®-A7 secure core to be controlled in the secure monitor (TF-A or OP-TEE).

Information

RCC owns one prescaler per TIM group corresponding to APB1 and APB2 buses: TIMG1PRE and TIMG2PRE, respectively. The allocation to Cortex-A7 or the Cortex-M4 should ideally be done on a per group basis to get independent clocking setup on each side, this is why the TIM instances groups are shown in the summary table below.

Click on to expand or collapse the legend...

STM32MP15 internal peripherals

Check boxes illustrate the possible peripheral allocations supported by STM32 MPU Embedded Software:

• ☐ means that the peripheral can be assigned to the given runtime context.
• ☑ means that the peripheral is assigned by default to the given runtime context and that the peripheral is mandatory for the STM32 MPU Embedded Software distribution.
• ⬚ means that the peripheral can be assigned to the given runtime context, but this configuration is not supported in STM32 MPU Embedded Software distribution.
• ✓ is used for system peripherals that cannot be unchecked because they are hardware connected in the device.

Refer to How to assign an internal peripheral to an execution context for more information on how to assign peripherals manually or via STM32CubeMX.
The present chapter describes STMicroelectronics recommendations or choice of implementation. Additional possiblities might be described in STM32MP15 reference manuals.

Domain	Peripheral	Runtime allocation				Comment
		Instance	Cortex-A7 secure (OP-TEE)	Cortex-A7 non-secure (Linux)	Cortex-M4 (STM32Cube)
Core/Timers	TIM	TIM1 (APB2 group)		☐	☐	Assignment (single choice)
		TIM2 (APB1 group)		☐	☐	Assignment (single choice)
		TIM3 (APB1 group)		☐	☐	Assignment (single choice)
		TIM4 (APB1 group)		☐	☐	Assignment (single choice)
		TIM5 (APB1 group)		☐	☐	Assignment (single choice)
		TIM6 (APB1 group)		☐	☐	Assignment (single choice)
		TIM7 (APB1 group)		☐	☐	Assignment (single choice)
		TIM8 (APB2 group)		☐	☐	Assignment (single choice)
		TIM12 (APB1 group)	☐	☐	☐	Assignment (single choice) TIM12 or TIM15 can be used for HSI/CSI calibration
		TIM13 (APB1 group)		☐	☐	Assignment (single choice)
		TIM14 (APB1 group)		☐	☐	Assignment (single choice)
		TIM15 (APB2 group)	☐	☐	☐	Assignment (single choice) TIM12 or TIM15 can be used for HSI/CSI calibration
		TIM16 (APB2 group)		☐	☐	Assignment (single choice)
		TIM17 (APB2 group)		☐	☐	Assignment (single choice)

3.2.3. On STM32MP25x lines 

STM32MP2 internal peripherals assignment table template

| rowspan="17" | Core/Timers | rowspan="17" | TIM | TIM1 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM10 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM11 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM12 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM13 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM14 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM15 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM16 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM17 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM2 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM20 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM3 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM4 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM5 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM6 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM7 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |- | TIM8 | ⬚^OP-TEE | ☐ | ⬚ | ☐ | | |-

|}

4. Software frameworks and drivers

Below are listed the software frameworks and drivers managing the TIM peripheral for the embedded software components listed in the above tables.

• Linux^®: PWM, the IIO, and the Counter frameworks
• OP-TEE: OP-TEE TIM driver , to perform HSI and CSI calibrations in RCC
• STM32Cube: HAL TIM driver

5. How to assign and configure the peripheral

The peripheral assignment can be done via the STM32CubeMX graphical tool (and manually completed if needed).
This tool also helps to configure the peripheral:

• partial device trees (pin control and clock tree) generation for the OpenSTLinux software components,
• HAL initialization code generation for the STM32CubeMPU Package.

The configuration is applied by the firmware running in the context in which the peripheral is assigned.

For Linux kernel configuration, please refer to TIM device tree configuration and TIM Linux driver articles.

6. How to go further

STM32 cross-series timer overview application note.