pmpcfg5

PMP Configuration Register 5

PMP entry configuration

Attributes

Defining Extension

  • Smpmp, version >= 0

CSR Address

0x3a5

Length

32-bit

Privilege Mode

M

Format

pmpcfg5 format
Figure 1. pmpcfg5 format

Field Summary

Name Location Type Reset Value

pmpcfg5.pmp20cfg

7:0

[when,"(NUM_PMP_ENTRIES > 20)"] RW-R [when,"(NUM_PMP_ENTRIES ⇐ 20)"] RO

[when,"(NUM_PMP_ENTRIES > 20)"] UNDEFINED_LEGAL [when,"(NUM_PMP_ENTRIES ⇐ 20)"] 0

pmpcfg5.pmp21cfg

15:8

[when,"(NUM_PMP_ENTRIES > 21)"] RW-R [when,"(NUM_PMP_ENTRIES ⇐ 21)"] RO

[when,"(NUM_PMP_ENTRIES > 21)"] UNDEFINED_LEGAL [when,"(NUM_PMP_ENTRIES ⇐ 21)"] 0

pmpcfg5.pmp22cfg

23:16

[when,"(NUM_PMP_ENTRIES > 22)"] RW-R [when,"(NUM_PMP_ENTRIES ⇐ 22)"] RO

[when,"(NUM_PMP_ENTRIES > 22)"] UNDEFINED_LEGAL [when,"(NUM_PMP_ENTRIES ⇐ 22)"] 0

pmpcfg5.pmp23cfg

31:24

[when,"(NUM_PMP_ENTRIES > 23)"] RW-R [when,"(NUM_PMP_ENTRIES ⇐ 23)"] RO

[when,"(NUM_PMP_ENTRIES > 23)"] UNDEFINED_LEGAL [when,"(NUM_PMP_ENTRIES ⇐ 23)"] 0

Fields

pmp20cfg

Location

7:0

Description

PMP configuration for entry 20

The bits are as follows:

Name Location Description

L

7

Locks the entry from further modification. Additionally, when set, PMP checks also apply to M-mode for the entry.

-

6:5

Reserved Writes shall be ignored.

A

4:3

Address matching mode. One of:

[when="PMP_GRANULARITY < 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NA4* (2) - Naturally aligned four-byte region
* *NAPOT* (3) - Naturally aligned power of two
[when="PMP_GRANULARITY >= 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NAPOT* (3) - Naturally aligned power of two

Naturally aligned four-byte region, NA4 (2), is not valid (not needed when the PMP granularity is larger than 4 bytes).

X

2

When clear, instruction fetches cause an Access Fault for the matching region and privilege mode.

W

1

When clear, stores and AMOs cause an Access Fault for the matching region and privilege mode.

R

0

When clear, loads cause an Access Fault for the matching region and privilege mode.

The combination of R = 0, W = 1 is reserved.

Type
RW-R
RO
Reset value
UNDEFINED_LEGAL
0

pmp21cfg

Location

15:8

Description

PMP configuration for entry 21

The bits are as follows:

Name Location Description

L

15

Locks the entry from further modification. Additionally, when set, PMP checks also apply to M-mode for the entry.

-

14:13

Reserved Writes shall be ignored.

A

12:11

Address matching mode. One of:

[when="PMP_GRANULARITY < 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NA4* (2) - Naturally aligned four-byte region
* *NAPOT* (3) - Naturally aligned power of two
[when="PMP_GRANULARITY >= 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NAPOT* (3) - Naturally aligned power of two

Naturally aligned four-byte region, NA4 (2), is not valid (not needed when the PMP granularity is larger than 4 bytes).

X

10

When clear, instruction fetches cause an Access Fault for the matching region and privilege mode.

W

9

When clear, stores and AMOs cause an Access Fault for the matching region and privilege mode.

R

8

When clear, loads cause an Access Fault for the matching region and privilege mode.

The combination of R = 0, W = 1 is reserved.

Type
RW-R
RO
Reset value
UNDEFINED_LEGAL
0

pmp22cfg

Location

23:16

Description

PMP configuration for entry 22

The bits are as follows:

Name Location Description

L

23

Locks the entry from further modification. Additionally, when set, PMP checks also apply to M-mode for the entry.

-

22:21

Reserved Writes shall be ignored.

A

20:19

Address matching mode. One of:

[when="PMP_GRANULARITY < 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NA4* (2) - Naturally aligned four-byte region
* *NAPOT* (3) - Naturally aligned power of two
[when="PMP_GRANULARITY >= 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NAPOT* (3) - Naturally aligned power of two

Naturally aligned four-byte region, NA4 (2), is not valid (not needed when the PMP granularity is larger than 4 bytes).

X

18

When clear, instruction fetches cause an Access Fault for the matching region and privilege mode.

W

17

When clear, stores and AMOs cause an Access Fault for the matching region and privilege mode.

R

16

When clear, loads cause an Access Fault for the matching region and privilege mode.

The combination of R = 0, W = 1 is reserved.

Type
RW-R
RO
Reset value
UNDEFINED_LEGAL
0

pmp23cfg

Location

31:24

Description

PMP configuration for entry 23

The bits are as follows:

Name Location Description

L

31

Locks the entry from further modification. Additionally, when set, PMP checks also apply to M-mode for the entry.

-

30:29

Reserved Writes shall be ignored.

A

28:27

Address matching mode. One of:

[when="PMP_GRANULARITY < 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NA4* (2) - Naturally aligned four-byte region
* *NAPOT* (3) - Naturally aligned power of two
[when="PMP_GRANULARITY >= 2"]
* *OFF* (0) - Null region (disabled)
* *TOR* (1) - Top of range
* *NAPOT* (3) - Naturally aligned power of two

Naturally aligned four-byte region, NA4 (2), is not valid (not needed when the PMP granularity is larger than 4 bytes).

X

26

When clear, instruction fetches cause an Access Fault for the matching region and privilege mode.

W

25

When clear, stores and AMOs cause an Access Fault for the matching region and privilege mode.

R

24

When clear, loads cause an Access Fault for the matching region and privilege mode.

The combination of R = 0, W = 1 is reserved.

Type
RW-R
RO
Reset value
UNDEFINED_LEGAL
0

Software write

This CSR may store a value that is different from what software attempts to write.

When a software write occurs (e.g., through csrrw), the following determines the written value:

pmp20cfg = if ((CSR[pmpcfg5].pmp20cfg & 0x80) == 0) {
  # entry is not locked
  if (!(((csr_value.pmp20cfg & 0x1) == 0) && ((csr_value.pmp20cfg & 0x2) == 0x2))) {
    # not R = 0, W =1, which is reserved
    if ((PMP_GRANULARITY < 2) ||
        ((csr_value.pmp20cfg & 0x18) != 0x10)) {
      # NA4 is not allowed when PMP granularity is larger than 4 bytes
      return csr_value.pmp20cfg;
    }
  }
}
# fall through: keep old value
return CSR[pmpcfg5].pmp20cfg;

pmp21cfg = if ((CSR[pmpcfg5].pmp21cfg & 0x80) == 0) {
  # entry is not locked
  if (!(((csr_value.pmp21cfg & 0x1) == 0) && ((csr_value.pmp21cfg & 0x2) == 0x2))) {
    # not R = 0, W =1, which is reserved
    if ((PMP_GRANULARITY < 2) ||
        ((csr_value.pmp21cfg & 0x18) != 0x10)) {
      # NA4 is not allowed when PMP granularity is larger than 4 bytes
      return csr_value.pmp21cfg;
    }
  }
}
# fall through: keep old value
return CSR[pmpcfg5].pmp21cfg;

pmp22cfg = if ((CSR[pmpcfg5].pmp22cfg & 0x80) == 0) {
  # entry is not locked
  if (!(((csr_value.pmp22cfg & 0x1) == 0) && ((csr_value.pmp22cfg & 0x2) == 0x2))) {
    # not R = 0, W =1, which is reserved
    if ((PMP_GRANULARITY < 2) ||
        ((csr_value.pmp22cfg & 0x18) != 0x10)) {
      # NA4 is not allowed when PMP granularity is larger than 4 bytes
      return csr_value.pmp22cfg;
    }
  }
}
# fall through: keep old value
return CSR[pmpcfg5].pmp22cfg;

pmp23cfg = if ((CSR[pmpcfg5].pmp23cfg & 0x80) == 0) {
  # entry is not locked
  if (!(((csr_value.pmp23cfg & 0x1) == 0) && ((csr_value.pmp23cfg & 0x2) == 0x2))) {
    # not R = 0, W =1, which is reserved
    if ((PMP_GRANULARITY < 2) ||
        ((csr_value.pmp23cfg & 0x18) != 0x10)) {
      # NA4 is not allowed when PMP granularity is larger than 4 bytes
      return csr_value.pmp23cfg;
    }
  }
}
# fall through: keep old value
return CSR[pmpcfg5].pmp23cfg;