AES Module Programming Guide
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SWRU543–January 2019
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Advance Encryption Standard Accelerator (AES)
AES Interrupt Mode
The application can use software interrupts to control the flow of Context In, Context Out, Data In, and
Data Out requests. To enable these interrupts:
1. When the device has been initialized, by following the initialization sequences described in
Section 17.3.1.1 and Section 17.3.1.2, the application can enable the AES module interrupts through
the AES Interrupt Enable (AES_IRQENABLE) register.
2. Load the input buffers, AES_DATA_IN_n, with data.
NOTE: If the application uses interrupt mode, an interrupt is generated for each block of processed
data. To support larger data flow, AES µDMA mode should be used and the bits in the
AES_IRQENABLE register should be cleared.
AES DMA Mode
When AES DMA mode is enabled, the AES_IRQENABLE register should be cleared. To enable the µDMA
to transfer data, follow these steps:
1. When the AES module has been initialized, enable the AES module µDMA channels by programming
the DMA Channel Map Select n ( DMA_CHMAPn ) register in the µDMA module. Refer to Figure 17-1
for the channel map associated with AES.
2. Configure the dma_done interrupts by programming the AES DMA Masked Interrupt Status
(DTHE_AES_MIS) register.
3. Enable the µDMA channels in the AES by programming the µDMA enable bits in the AES System
Configuration (AES_SYSCONFIG) register.
The input buffer registers, AES_DATA_IN_n, are now loaded.
17.3.1.4 AES Events Servicing
Interrupt Servicing
This section describes the event servicing of the module. Figure 17-13 shows the AES interrupt service.
The registers used during event servicing follow:
• AES_IRQSTATUS
• AES_KEY1_n
• AES_KEY2_n
• AES_IV_IN_n
• AES_DATA_IN_n
• AES_TAG_OUT_n
• AES_IRQENABLE
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