Hi, this series introduces support to resume from IO+DDR. IO+DDR is a low power mode of am62a and am62p in which nearly everything is powered off except DDR which is in self-refresh and a few pins which detect activity and can wakeup the system again.
On resume uboot SPL is loaded and checks if this is a IO+DDR resume. If it is, the DDR initialization sequence in k3-ddrss differs slightly as it has to get the DDR out of the self-refresh. Afterward a specific address determined from DT is used to get the metadata that stores relevant context addresses. The context is restored using the tisci message TI_SCI_MSG_MIN_CONTEXT_RESTORE. At the end all further initializations are skipped and uboot SPL directly jumps into the DM resume address which takes care of the rest. k3-ddrss is using absolute register accesses at the moment. I am trying to submit syscon DT patches upstream to access these through syscon, unfortunately there is ongoing discussion regarding syscon. I tested this on am62a. Best, Markus Signed-off-by: Markus Schneider-Pargmann (TI.com) <[email protected]> --- Changes in v8: - Create and use am62xx-lpm-common for am62xx lpm common functions - Create platform dependent functions in k3-ddrss in k3_ddrss_data - Align am62a and am62p initialization regarding caches and QoS - Link to v7: https://lore.kernel.org/r/20251210-topic-am62-ioddr-v2025-04-rc1-v7-0-f113b156f...@baylibre.com Changes in v7: - Removed parent nodes bootph-pre-ram properties as not necessary anymore. - Added missing new line in arm: mach-k3: common: Helper for LPM meta data address from DT - Split off LPM specific ddr code into its own file k3-ddrss-lpm - Rename lpm_ops->restore_context to lpm_ops->min_context_restore - Pulled patch to add wakeup check helpers before the IO isolation removal to remove later cleanup of wkup_ctrl_remove_can_io_isolation_if_set() - Some reviewed-bys and tested-bys removed due to changes in the patches - Link to v6: https://lore.kernel.org/r/20251120-topic-am62-ioddr-v2025-04-rc1-v6-0-6dd99a727...@baylibre.com Changes in v6: - Add comment for last part of removing can io isolation - Only mention a single kconfig symbol in the commit message - Add defines for timeouts in k3-ddrss - Link to v5: https://lore.kernel.org/r/20251110-topic-am62-ioddr-v2025-04-rc1-v5-0-980ee0036...@baylibre.com Changes in v5: - Fixed compile warnings - Link to v4: https://lore.kernel.org/r/20251030-topic-am62-ioddr-v2025-04-rc1-v4-0-4cef18af0...@baylibre.com Changes in v4: - Copy lpm_meta_data into the stack to be able to debug unstable memory issues - Add missing comments about ctx_lo and ctx_hi - Use absolute addresses for k3-ddrss CANUART_WAKE_STAT1 and CANUART_WAKE_OFF_MODE_STAT to avoid using addresses outside of the range given in the devicetree - Remove the cherry picked devicetree patches as they are already included now - In lpm_resume_from_ddr() print upper and lower 32bit of the meta data values separately. - Link to v3: https://lore.kernel.org/r/20250623-topic-am62-ioddr-v2025-04-rc1-v3-0-a4da322c1...@baylibre.com Changes in v3: - Use wait_for_bit helpers in k3-ddrss where possible and add panic messages for easier debugging - Link to v2: https://lore.kernel.org/r/20250613-topic-am62-ioddr-v2025-04-rc1-v2-0-3d233aaea...@baylibre.com Changes in v2: - Remove 'default n' from K3_IODDR - Pick devicetree patches from upstream instead of mailinglist - Link to v1: https://lore.kernel.org/r/20250311-topic-am62-ioddr-v2025-04-rc1-v1-0-666de9c10...@baylibre.com --- Markus Schneider-Pargmann (TI.com) (13): arm: mach-k3: Kconfig: Add symbol for IO+DDR Low Power Mode arm: mach-k3: am62xx-lpm-common: Add CANUART wakeup check helpers arm: mach-k3: Remove CANUART IO isolation ram: k3-ddrss: Add support for DDR in self-refresh firmware: ti_sci: Add TI_SCI_MSG_MIN_CONTEXT_RESTORE arm: mach-k3: am62xx-lpm-common: Add lpm_resume_from_ddr arm: mach-k3: am62xx-lpm-common: Helper for LPM meta data address from DT arm: mach-k3: am62a7_init: Resume on LPM exit arm: mach-k3: am62p5_init: Resume on LPM exit arm: dts: k3-am62a: Add r5 device nodes arm: dts: k3-am62p: Add r5 device nodes configs: am62ax_evm_r5: Enable IODDR resume support configs: am62p_evm_r5_defconfig: Enable IODDR resume support arch/arm/dts/k3-am62a7-sk-u-boot.dtsi | 8 ++ arch/arm/dts/k3-am62p5-sk-u-boot.dtsi | 8 ++ arch/arm/mach-k3/Kconfig | 8 ++ arch/arm/mach-k3/Makefile | 3 + arch/arm/mach-k3/am62ax/am62a7_init.c | 14 +++ arch/arm/mach-k3/am62px/am62p5_init.c | 14 +++ arch/arm/mach-k3/am62x/am625_init.c | 5 + arch/arm/mach-k3/am62xx-lpm-common.c | 220 +++++++++++++++++++++++++++++++++ arch/arm/mach-k3/am62xx-lpm-common.h | 19 +++ configs/am62ax_evm_r5_defconfig | 1 + configs/am62px_evm_r5_defconfig | 1 + drivers/firmware/ti_sci.c | 38 ++++++ drivers/firmware/ti_sci.h | 16 +++ drivers/ram/k3-ddrss/Makefile | 1 + drivers/ram/k3-ddrss/k3-ddrss-lpm.c | 181 +++++++++++++++++++++++++++ drivers/ram/k3-ddrss/k3-ddrss-lpm.h | 20 +++ drivers/ram/k3-ddrss/k3-ddrss.c | 26 +++- include/linux/soc/ti/ti_sci_protocol.h | 9 ++ 18 files changed, 591 insertions(+), 1 deletion(-) --- base-commit: 0e0a198a68be71148f5ec27ef86796174f91436f change-id: 20250306-topic-am62-ioddr-v2025-04-rc1-0b3a0ffe92b1 Best regards, -- Markus Schneider-Pargmann (TI.com) <[email protected]>
