On 09/11/2022 00:45, Georgi Vlaev wrote: > This series introduces necessary ti_sci driver functionality in > preparation of supporting DeepSleep mode for suspend to mem on TI > K3 AM62x. This version is a fixup and rebase of the patch series by > Dave Gerlach [1]. It applies on top of v6.1-rc4. > > Deep Sleep mode is described in section "5.2.4.4 DeepSleep" of the > AM62x Technical Reference Manual [2]. > > The kernel triggers entry to Deep Sleep mode through the mem suspend > transition with the following: > > * Use a TF-A binary that supports PSCI_SYSTEM_SUSPEND call. This causes > system to use PSCI system suspend as last step of mem sleep. > > * The firmware requires that the OS sends a TISCI_MSG_PREPARE_SLEEP > message in order to provide details about suspend, so we must add the > ability to send this message. We also add TISCI_MSG_LPM_WAKE_REASON > and TISCI_MSG_SET_IO_ISOLATION messages as part of a new PM ops. These > messages are part of the TISCI PM Low Power Mode API [3]. (Patch 2) > > * A memory address must be provided to the firmware using the above > message, which is allocated and managed by dma_alloc_coherent() > and friends. (Patch 3) > > * System must load firmware to a specific location before Deep Sleep is > entered, and this is accomplished using a memory region in device > tree to indicate where this firmware should be loaded, and also a > "firmware-name" property to indicate the name of the firmware > to load. The ti_sci driver checks in its pm handler to see if > the firmware has been loaded and if not, loads it. (Patch 4) > > * Finally, the ti_sci driver must actually send TISCI_MSG_PREPARE_SLEEP > message to firmware with the above information included, which it > does during the driver suspend handler when PM_MEM_SUSPEND is the > determined state being entered. (Patch 5) > > This is tested on am625-sk using a limited dts with all devices disabled > apart from cpu0, main_uart0, i2c, rtc, mmc/sd, dmsc, and secure_proxy_main. > > Testing this sequence requires K3 sdhci suspend/resume support [4], > enable the wkup_rtc in the am625-sk.dts, disable devices that don't > support system suspend/resume like OSPI and CPSW3G. > > In can be tested on the following branch: > https://github.com/gvlaev/linux/tree/upstream-v6.2/lpm-ti-sci-v1 > > Changelog: > v2: > - Addressed comments received for v1 series [1]. > - Updated v1 patch 5 to use pm notifier to avoid firmware loading > issues. > - Dropped the reserved region requirement and allocate DMA memory > instead. The reserved region binding patch is also removed. > - Introduce two more TISCI LPM messages that are supported in SysFW. > - Fixes in error handling. > > [1] https://lore.kernel.org/lkml/20220421203659.27853-1-d-gerlach@xxxxxx > [2] https://www.ti.com/lit/pdf/spruiv7 > [3] https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html > [4] https://lore.kernel.org/lkml/20220408124338.27090-1-a-govindraju@xxxxxx > > Dave Gerlach (5): > dt-bindings: ti, sci: Add lpm region and firmware-name > firmware: ti_sci: Introduce Power Management Ops > firmware: ti_sci: Allocate memory for the LPM modes > firmware: ti_sci: Use dt provided fw name and address to load at > suspend time > firmware: ti_sci: Introduce prepare system suspend call > > .../bindings/arm/keystone/ti,sci.yaml | 21 +- > drivers/firmware/ti_sci.c | 356 ++++++++++++++++++ > drivers/firmware/ti_sci.h | 64 +++- > include/linux/soc/ti/ti_sci_protocol.h | 44 +++ > 4 files changed, 480 insertions(+), 5 deletions(-) > > > base-commit: f0c4d9fc9cc9462659728d168387191387e903cc Tested-by: Roger Quadros <rogerq@xxxxxxxxxx> Tested this with am65-CPSW suspend/resume patches [1] [1] - https://lore.kernel.org/netdev/20221104132310.31577-3-rogerq@xxxxxxxxxx/T/ --
