3.4.3. PrimeCell ID Registers 0-3

The PrimeCell ID value is a 32-bit value. However, to ensure that it is accessible in all systems, the 32 bits are implemented as four 8-bit registers that can be accessed separately as the least significant eight bits of addresses 0xFF0, 0xFF4, 0xFF8, and 0xFFC.

The registers can conceptually be treated as a single register that holds a 32-bit PrimeCell ID value. You can use the register for automatic BIOS configuration. The pcell_id Register is set to 0xB105F00D. You can access the register with one wait state. Table 3.8 lists the register bit assignments.

Table 3.8. pcell_id Register bit assignments

pcell_id_0-3 register
BitsReset valueRegisterBitsDescription
--pcell_id_3[31:8]Read undefined
[31:24]0xB1pcell_id_3[7:0]These bits read back as 0xB1
--pcell_id_2[31:8]Read undefined
[23:16]0x05pcell_id_2[7:0]These bits read back as 0x05
--pcell_id_1[31:8]Read undefined
[15:8]0xF0pcell_id_1[7:0]These bits read back as 0xF0
--pcell_id_0[31:8]Read undefined
[7:0]0x0Dpcell_id_0[7:0]These bits read back as 0x0D

Figure 3.3 shows the register bit assignments.

Figure 3.3. pcell_id Register bit assignments

The following subsections describe the pcell_id Registers:

Note

You cannot read these registers in the Reset state.

PrimeCell Identification Register 0

The pcell_id_0 Register is hard-coded and the fields within the register determine the reset value. Table 3.9 lists the register bit assignments.

Table 3.9. pcell_id_0 Register bit assignments

BitsNameFunction
[31:8]-Reserved, read undefined
[7:0]pcell_id_0These bits read back as 0x0D

PrimeCell Identification Register 1

The pcell_id_1 Register is hard-coded and the fields within the register determine the reset value. Table 3.10 lists the register bit assignments.

Table 3.10. pcell_id_1 Register bit assignments

BitsNameFunction
[31:8]-Reserved, read undefined
[7:0]pcell_id_1These bits read back as 0xF0

PrimeCell Identification Register 2

The pcell_id_2 Register is hard-coded and the fields within the register determine the reset value. Table 3.11 lists the register bit assignments.

Table 3.11. pcell_id_2 Register bit assignments

BitsNameFunction
[31:8]-Reserved, read undefined
[7:0]pcell_id_2These bits read back as 0x05

PrimeCell Identification Register 3

The pcell_id_3 Register is hard-coded and the fields within the register determine the reset value. Table 3.12 lists the register bit assignments.

Table 3.12. pcell_id_3 Register bit assignments

BitsNameFunction
[31:8]-Reserved, read undefined
[7:0]pcell_id_3These bits read back as 0xB1
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