M-Boot ROM Description
547
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
ROM Code and Peripheral Booting
Table 6-8. M-Boot ROM Boot Mode GPIO Assignments (continued)
M-Boot ROM Boot
Mode
Peripheral
Boot Function
Name for pin
Direction
GPIO(s) used
Pin Mux Assignment
D6
Input
PB0_GPIO8
0(default)
0(default)
Master(default)
D7
Input
PB1_GPIO9
0(default)
0(default)
Master(default)
HOST_CTRL
Input
PE3_GPIO27
0(default)
0(default)
Master(default)
DSP_CTRL
Ouput
PE2_GPIO26
0(default)
0(default)
Master(default)
CAN Boot Mode
CAN0
CAN0_RX
Input
PB4_GPIO12
5
0(default)
Master(default)
CAN_TX
Output
PB5_GPIO13
5
0(default)
Master(default)
Ethernet Boot
Mode
EMAC0
MII_TXD3
Output
PC4_GPIO68
3
0(default)
Master(default)
MII_TXD2
Output
PH3_GPIO51
9
0(default)
Master(default)
MII_TXD1
Output
PH4_GPIO52
9
0(default)
Master(default)
MII_TXD0
Output
PH5_GPIO53
9
0(default)
Master(default)
MII_RXD3
Input
PF5_GPIO37
3
0(default)
Master(default)
MII_RXD2
Input
PG0_GPIO40
Alternate
12
Master(default)
MII_RXD1
Input
PG1_GPIO41
Alternate
12
Master(default)
MII_RXD0
Input
PH1_GPIO49
Alternate
12
Master(default)
MII_TXER
Output
PG7_GPIO47
3
0(default)
Master(default)
MII_RXDV
Input
PG3_GPIO43
Alternate
12
Master(default)
MII_MDIO
Bi-directional
PE6_GPIO30
Alternate
12
Master(default)
MII_TXEN
Output
PH6_GPIO54
Alternate
12
Master(default)
MII_TXCK
Input
PH7_GPIO55
Alternate
12
Master(default)
MII_RXER
Input
PJ0_GPIO56
3
0(default)
Master(default)
MII_RXCK
Input
PJ2_GPIO58
Alternate
12
Master(default)
MII_MDC
Output
PJ3_GPIO59
Alternate
12
Master(default)
MII_COL
Input
PJ4_GPIO60
Alternate
12
Master(default)
MII_CRS
Input
PJ5_GPIO61
Alternate
12
Master(default)
MII_PHYINTRn
Input
PJ6_GPIO62
Alternate
12
Master(default)
MII_PHYRSTn
Output
PJ7_GPIO63
Alternate
12
Master(default)
Boot from SSI0
master
SSI0
SSI0_CS
Input
PA3_GPIO3
1
0(default)
Master(default)
(Boot Mode 9
SSI0_CLK
Input
PA2_GPIO2
1
0(default)
Master(default)
SSI0_TX
Output
PA5_GPIO5
1
0(default)
Master(default)
SSI0_CRX
Input
PA4_GPIO4
1
0(default)
Master(default)
Boot from I2C0
master
I2C0
I2C0_CLK
Input
PB2_GPIO10
1
0(default)
Master(default)
(Boot mode 10)
I2C0_DATA
Bi-directional
PB3_GPIO11
1
0(default)
Master(default)
6.5.10 M-Boot ROM Functional Flow
As shown in
, ResetISR is the main function that is called whenever M-Boot ROM is executed
after a reset. This section explains the flow of M-Boot ROM following the function call sequence.
6.5.10.1 RESETISR()
•
Call mbrom_change_dividers_checkfast_boot()
–
If the source of the reset is either POR / XRSn
•
Configure M3SSCLK and SYSDIVSEL = OSCCLK
•
Configure flash to power-up faster
•
CSM initialization
–
Read OTPSECLOCK
–
Read Z1 CSM and Z2 CSM registers
•
Device configuration initialization
•
If the source of the reset is POR, initialize all RAMs (Cx RAM, SxRAM, M2CMSGRAM) to 0x0000
•
If the source of the reset is NOT POR, zero-out stack used for boot ROM