Changes

446 bytes added ,  08:15, 15 May 2021
Notes on JTAG and lockout
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=== Cluster C ===
 
=== Cluster C ===
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The JTAG pins are multiplexed between NV_JTAG and ARM_JTAG by the TRST pin:
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* NV_JTAG contains a single TAP (ID 0x221173D7) for boundary scan board verification.
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* ARM_JTAG contains two debugging TAPs for CoreSight (ID 0x5BA00477) and BPMP (ID 0x4F1F0F0F).
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Note: NV_JTAG and ARM_JTAG are locked out by [[Fuses#Cache|FUSE_ARM_JTAG_DIS]] on production devices.
    
{| class=wikitable
 
{| class=wikitable
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| 4 || JTAG_TCK || || 0-1.8V || || ||  
 
| 4 || JTAG_TCK || || 0-1.8V || || ||  
 
|-
 
|-
| 5 || JTAG_RTCK || || 0-1.8V || || ||  
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| 5 || JTAG_RTCK || || 0-1.8V || || || Unused for NV_JTAG
 
|-
 
|-
 
| 6 || UART1_RTS || || 0-1.8V || || || UART-A RTS Flow control
 
| 6 || UART1_RTS || || 0-1.8V || || || UART-A RTS Flow control
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| 9 || JTAG_TMS || || 0-1.8V || || ||  
 
| 9 || JTAG_TMS || || 0-1.8V || || ||  
 
|-
 
|-
| 10 || JTAG_TRST_N || || 0-1.8V || || ||  
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| 10 || JTAG_TRST_N || || 0-1.8V || || || Not a TAP reset; Multiplexes between NV_JTAG (HI) and ARM_JTAG (LO)
 
|-
 
|-
 
| 11 || +1.8V || || 0-1.8V || || ||  
 
| 11 || +1.8V || || 0-1.8V || || ||