To support eMMC boot mode across a
device warm reset, eMMC flash has the following requirements:
- The reset line must be
connected to the eMMC flash input reset pin.
- The eMMC flash ext_csd[162]
RST_n_ENABLE must be set to the expected configuration for the warm-reset
signal to propagate to the flash device for the boot process to succeed.
Possible configurations are shown in Table 4-33.
Note: For warm_reset eMMC boot to function correctly, 0x1 must be
written to RST_n_ENABLE in the ext_csd[162] Register. This will enable the RST_n
signal.
Table 4-33 ext_csd[162] Register
| Bit |
Field |
Type |
Description |
| 7:2 |
Reserved |
|
Reserved |
| 1:0 |
RST_n_ENABLE |
R/W |
0x0: RST_n signal is temporarily disabled (default) 0x1: RST_n signal is permanently
enabled 0x2 RST_n signal is
permanently disabled 0x3:
Reserved |