Skip to content

Commit bdd2233

Browse files
committed
Merge branch 'change/improve_xip_docs_on_p4_v5.3' into 'release/v5.3'
psram: improved xip psram docs on p4 (v5.3) See merge request espressif/esp-idf!32384
2 parents 8595590 + 21b861e commit bdd2233

File tree

2 files changed

+8
-4
lines changed

2 files changed

+8
-4
lines changed

components/esp_psram/esp32p4/Kconfig.spiram

Lines changed: 7 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -57,7 +57,7 @@ menu "PSRAM config"
5757
PSRAM
5858

5959
config SPIRAM_XIP_FROM_PSRAM
60-
bool "Enable Executable in place from (XiP) from PSRAM feature"
60+
bool "Enable Executable in place from (XiP) from PSRAM feature (READ HELP)"
6161
default n
6262
select SPIRAM_FETCH_INSTRUCTIONS
6363
select SPIRAM_RODATA
@@ -70,7 +70,12 @@ menu "PSRAM config"
7070
does not have to be placed in IRAM. Therefore codes that need to be executing during Flash
7171
operations can continue working normally.
7272

73-
Enabling this option will have better performance (see External RAM documentation for more details).
73+
Because P4 flash and PSRAM are using two separate SPI buses, moving flash content to PSRAM will
74+
actually increase the load of the PSRAM MSPI bus, so the exact impact on performance will be dependent
75+
on your app usage of PSRAM. For example, as the PSRAM bus speed could be much faster than flash bus speed,
76+
if the instructions and data that are used to be in flash are not accessed very frequently, you might
77+
get better performance with this option enabled. We suggest doing performance profiling to determine
78+
if enabling this option.
7479

7580
config SPIRAM_FLASH_LOAD_TO_PSRAM
7681
bool

docs/en/api-guides/external-ram.rst

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -184,8 +184,7 @@ Remaining external RAM can also be added to the capability heap allocator using
184184

185185
The :ref:`CONFIG_SPIRAM_XIP_FROM_PSRAM` option enables the executable in place (XiP) from PSRAM feature. With this option sections that are normally placed in flash ,``.text`` (for instructions) and ``.rodata`` (for read only data), will be loaded in PSRAM.
186186

187-
With this option enabled, the cache will not be disabled during an SPI1 flash operation, so code that requires executing during an SPI1 Flash operation does not have to be placed in internal RAM. Because P4 Flash and PSRAM are using two separate SPI buses, moving Flash content to PSRAM will actually increase the load of the PSRAM MSPI bus, so the access speed is relatively slower. The exact impact on performance will be very dependent on your apps usage of PSRAM, and we suggest doing performance profiling to determine if enabling this option will significantly impact your app's performance.
188-
187+
With this option enabled, the cache will not be disabled during an SPI1 flash operation, so code that requires executing during an SPI1 flash operation does not have to be placed in internal RAM. Because P4 flash and PSRAM are using two separate SPI buses, moving flash content to PSRAM will actually increase the load of the PSRAM MSPI bus, so the exact impact on performance will be dependent on your app usage of PSRAM. For example, as the PSRAM bus speed could be much faster than flash bus speed, if the instructions and data that are used to be in flash are not accessed very frequently, you might get better performance with this option enabled. We suggest doing performance profiling to determine if enabling this option.
189188

190189
Restrictions
191190
============

0 commit comments

Comments
 (0)