Table 18-81. Overlapping Region Descriptor Example (continued)
Region Description
RGDn
CP0
CP1
DMA1
DMA2
CP0 data & stack
2
rw-
—
—
—
RAM
CP0
→
CP1 shared data
2
3
r--
r--
—
—
CP1
→
CP0 shared data
4
CP1 data & stack
4
—
rw-
—
—
Shared DMA data
5
rw-
rw-
rw
rw
MPU
6
rw-
rw-
—
—
Peripheral
space
Peripherals
7
rw-
rw-
rw
—
In this example, there are eight descriptors used to span nine regions in the three main
spaces of the system memory map (flash, RAM, and peripheral space). Each region
indicates the specific permissions for each of the four bus masters and this definition
provides an appropriate set of shared, private and executable memory spaces.
Of particular interest are the two overlapping spaces: region descriptors 2 & 3 and 3 & 4.
The space defined by RGD2 with no overlap is a private data and stack area that provides
read/write access to CP0 only. The overlapping space between RGD2 and RGD3 defines
a shared data space for passing data from CP0 to CP1 and the access controls are defined
by the logical OR of the two region descriptors. Thus, CP0 has (rw- | r--) = (rw-)
permissions, while CP1 has (--- | r--) = (r--) permission in this space. Both DMA engines
are excluded from this shared processor data region. The overlapping spaces between
RGD3 and RGD4 defines another shared data space, this one for passing data from CP1
to CP0. For this overlapping space, CP0 has (r-- | ---) = (r--) permission, while CP1 has
(rw- | r--) = (rw-) permission. The non-overlapped space of RGD4 defines a private data
and stack area for CP1 only.
The space defined by RGD5 is a shared data region, accessible by all four bus masters.
Finally, the slave peripheral space mapped onto the IPS bus is partitioned into two
regions: one containing the MPU's programming model accessible only to the two
processor cores and the remaining peripheral region accessible to both processors and the
traditional DMA1 master.
This simple example is intended to show one possible application of the capabilities of
the MPU in a typical system.
Chapter 18 Memory Protection Unit (MPU)
K53 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
405
Содержание K53 Series
Страница 2: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 2 Freescale Semiconductor Inc...
Страница 58: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 58 Freescale Semiconductor Inc...
Страница 70: ...Orderable part numbers K53 Sub Family Reference Manual Rev 6 Nov 2011 70 Freescale Semiconductor Inc...
Страница 168: ...Human machine interfaces HMI K53 Sub Family Reference Manual Rev 6 Nov 2011 168 Freescale Semiconductor Inc...
Страница 206: ...Boot K53 Sub Family Reference Manual Rev 6 Nov 2011 206 Freescale Semiconductor Inc...
Страница 218: ...Security Interactions with other Modules K53 Sub Family Reference Manual Rev 6 Nov 2011 218 Freescale Semiconductor Inc...
Страница 342: ...PMC Memory Map Register Definition K53 Sub Family Reference Manual Rev 6 Nov 2011 342 Freescale Semiconductor Inc...
Страница 362: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 362 Freescale Semiconductor Inc...
Страница 384: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 384 Freescale Semiconductor Inc...
Страница 406: ...Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 406 Freescale Semiconductor Inc...
Страница 424: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 424 Freescale Semiconductor Inc...
Страница 514: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 514 Freescale Semiconductor Inc...
Страница 524: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 524 Freescale Semiconductor Inc...
Страница 546: ...Restrictions on Watchdog Operation K53 Sub Family Reference Manual Rev 6 Nov 2011 546 Freescale Semiconductor Inc...
Страница 594: ...Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 594 Freescale Semiconductor Inc...
Страница 628: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 628 Freescale Semiconductor Inc...
Страница 702: ...Flash Operation in Low Power Modes K53 Sub Family Reference Manual Rev 6 Nov 2011 702 Freescale Semiconductor Inc...
Страница 772: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 772 Freescale Semiconductor Inc...
Страница 808: ...Initialization Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 808 Freescale Semiconductor Inc...
Страница 864: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 864 Freescale Semiconductor Inc...
Страница 894: ...DAC Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 894 Freescale Semiconductor Inc...
Страница 908: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 908 Freescale Semiconductor Inc...
Страница 920: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 920 Freescale Semiconductor Inc...
Страница 926: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 926 Freescale Semiconductor Inc...
Страница 1092: ...FTM Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 1092 Freescale Semiconductor Inc...
Страница 1114: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1114 Freescale Semiconductor Inc...
Страница 1156: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1156 Freescale Semiconductor Inc...
Страница 1304: ...On The Go Operation K53 Sub Family Reference Manual Rev 6 Nov 2011 1304 Freescale Semiconductor Inc...
Страница 1334: ...USB Voltage Regulator Module Signal Descriptions K53 Sub Family Reference Manual Rev 6 Nov 2011 1334 Freescale Semiconductor Inc...
Страница 1388: ...Initialization Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 1388 Freescale Semiconductor Inc...
Страница 1514: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1514 Freescale Semiconductor Inc...
Страница 1622: ...Software restrictions K53 Sub Family Reference Manual Rev 6 Nov 2011 1622 Freescale Semiconductor Inc...
Страница 1694: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1694 Freescale Semiconductor Inc...
Страница 1704: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1704 Freescale Semiconductor Inc...
Страница 1734: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1734 Freescale Semiconductor Inc...
Страница 1800: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1800 Freescale Semiconductor Inc...
Страница 1822: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 1822 Freescale Semiconductor Inc...