| author | Suman Anna <s-anna@ti.com> | |
| Thu, 22 Nov 2018 11:39:03 +0000 (13:39 +0200) | ||
| committer | Suman Anna <s-anna@ti.com> | |
| Sun, 24 Feb 2019 02:56:38 +0000 (20:56 -0600) | ||
| commit | 696961f5004879c0ef4b7a5669392b17edd27aaf | |
| tree | 6a41015b38b27b279f3ea693284cf76a801aec5b | tree | snapshot (tar.xz tar.gz zip) |
| parent | 1e35777e53ecb9579fa38f8e3232a49b6e681195 | commit | diff |
soc: ti: pruss: enable OCP master ports in SYSCFG always
The PRUSS CFG module's SYSCFG register is used for managing the
PRCM clock management settings at the PRU-ICSS subsystem level,
and is being programmed for the PRCM Idle/Standby protocol properly
during probe and remove. The register is also programmed to enable
the OCP master ports (disable MStandby) by default during probe now
to allow the PRUs access to on-chip memories and peripherals outside
the PRUSS without having to do it in firmware (primarily for the PRU
Ethernet usecase currently, the firmware is not programming this
register).
NOTE:
1. The AM57xx TRM suggests to enable "No Standby" during the
Idle + Standby state to an Active/Normal state, but this
sequence is not documented in either of AM33xx and AM437x
SoCs. Furthermore, it did not have an impact on the working
of Ethernet Rx, so is left out.
2. This has an impact on the PM suspend/resume operation usually
(same bit is used to trigger PRU standby), and even when the
PRU cores are in halted state. The STANDBY_INIT has to be
re-programmed to initiate a standby sequence and have the PM
suspend/resume functional when PRUs are halted. This is already
handled in commit c1d6b33cb8f7 ("soc: ti: pruss: Fix system
suspend/MStandby config issues").
Signed-off-by: Suman Anna <s-anna@ti.com>
The PRUSS CFG module's SYSCFG register is used for managing the
PRCM clock management settings at the PRU-ICSS subsystem level,
and is being programmed for the PRCM Idle/Standby protocol properly
during probe and remove. The register is also programmed to enable
the OCP master ports (disable MStandby) by default during probe now
to allow the PRUs access to on-chip memories and peripherals outside
the PRUSS without having to do it in firmware (primarily for the PRU
Ethernet usecase currently, the firmware is not programming this
register).
NOTE:
1. The AM57xx TRM suggests to enable "No Standby" during the
Idle + Standby state to an Active/Normal state, but this
sequence is not documented in either of AM33xx and AM437x
SoCs. Furthermore, it did not have an impact on the working
of Ethernet Rx, so is left out.
2. This has an impact on the PM suspend/resume operation usually
(same bit is used to trigger PRU standby), and even when the
PRU cores are in halted state. The STANDBY_INIT has to be
re-programmed to initiate a standby sequence and have the PM
suspend/resume functional when PRUs are halted. This is already
handled in commit c1d6b33cb8f7 ("soc: ti: pruss: Fix system
suspend/MStandby config issues").
Signed-off-by: Suman Anna <s-anna@ti.com>
| drivers/soc/ti/pruss_soc_bus.c | diff | blob | history |