[PATCH 18/20] board: ti: evm: Store wakeup reason on scratchpad memory
Richard GENOUD
richard.genoud at bootlin.com
Fri May 22 17:57:40 CEST 2026
Le 30/04/2026 à 19:32, Andrew Davis a écrit :
> On 4/30/26 3:44 AM, Richard Genoud (TI) wrote:
>> From: Abhash Kumar Jha <a-kumar2 at ti.com>
>>
>> While resuming from suspend, the wakeup reason need to be stored
>> and this will be used by the Linux kernel once its up.
>>
>> Use the 32 bytes of MCU_PSRAM0_RAM area (addr = 0x40280000) to
>> store the wakeup reason.
>>
>> Read the value as soon as it starts and store it internally.
>>
>> Signed-off-by: Abhash Kumar Jha <a-kumar2 at ti.com>
>> ---
>> arch/arm/mach-k3/include/mach/j721e_hardware.h | 1 +
>> arch/arm/mach-k3/include/mach/j784s4_hardware.h | 1 +
>> board/ti/common/k3-lpm.h | 5 +++++
>> board/ti/j721e/evm.c | 9 +++++++++
>> board/ti/j784s4/evm.c | 9 +++++++++
>> 5 files changed, 25 insertions(+)
>>
>> diff --git a/arch/arm/mach-k3/include/mach/j721e_hardware.h b/arch/
>> arm/mach-k3/include/mach/j721e_hardware.h
>> index 587dd10eb1ea..d58e2b3e1bb2 100644
>> --- a/arch/arm/mach-k3/include/mach/j721e_hardware.h
>> +++ b/arch/arm/mach-k3/include/mach/j721e_hardware.h
>> @@ -47,6 +47,7 @@
>> /* MCU SCRATCHPAD usage */
>> #define TI_SRAM_SCRATCH_BOARD_EEPROM_START
>> CONFIG_SYS_K3_MCU_SCRATCHPAD_BASE
>> +#define TI_SRAM_SCRATCH_LPM_START 0x40280000
>
> Should this be a Kconfig option?
>
> Andrew
>
Yes, definitely.
Thanks!
>> #if defined(CONFIG_SYS_K3_SPL_ATF) && !defined(__ASSEMBLY__)
>> diff --git a/arch/arm/mach-k3/include/mach/j784s4_hardware.h b/arch/
>> arm/mach-k3/include/mach/j784s4_hardware.h
>> index dd51473419dd..2fc81902f879 100644
>> --- a/arch/arm/mach-k3/include/mach/j784s4_hardware.h
>> +++ b/arch/arm/mach-k3/include/mach/j784s4_hardware.h
>> @@ -46,6 +46,7 @@
>> /* MCU SCRATCHPAD usage */
>> #define TI_SRAM_SCRATCH_BOARD_EEPROM_START
>> CONFIG_SYS_K3_MCU_SCRATCHPAD_BASE
>> +#define TI_SRAM_SCRATCH_LPM_START 0x40280000
>> #if defined(CONFIG_SYS_K3_SPL_ATF) && !defined(__ASSEMBLY__)
>> diff --git a/board/ti/common/k3-lpm.h b/board/ti/common/k3-lpm.h
>> index a2141a0c25a8..dfd8f8486f08 100644
>> --- a/board/ti/common/k3-lpm.h
>> +++ b/board/ti/common/k3-lpm.h
>> @@ -13,5 +13,10 @@
>> /* PMIC register where the magic value resides */
>> #define K3_LPM_SCRATCH_PAD_REG 0xcb
>> +struct lpm_scratch_space {
>> + u16 wake_src;
>> + u16 reserved;
>> +} __packed;
>> +
>> #endif /* __K3_LPM_H */
>> diff --git a/board/ti/j721e/evm.c b/board/ti/j721e/evm.c
>> index 41eea1bdea95..a9f469fea1f7 100644
>> --- a/board/ti/j721e/evm.c
>> +++ b/board/ti/j721e/evm.c
>> @@ -474,6 +474,9 @@ err_free_gpio:
>> #if (IS_ENABLED(CONFIG_SPL_BUILD) &&
>> IS_ENABLED(CONFIG_TARGET_J7200_R5_EVM))
>> +#define LPM_WAKE_SOURCE_PMIC_GPIO 0x91
>> +#define LPM_WAKE_SOURCE_MAIN_IO 0x80
>> +
>> static void clear_isolation(void)
>> {
>> int ret;
>> @@ -498,12 +501,15 @@ bool j7xx_board_is_resuming(void)
>> {
>> struct udevice *pmica;
>> u32 pmctrl_val = readl(PMCTRL_IO_1);
>> + struct lpm_scratch_space *lpm_scratch;
>> int ret;
>> if (gd_k3_resuming() != K3_RESUME_STATE_UNKNOWN)
>> goto end;
>> + lpm_scratch = (struct lpm_scratch_space *)TI_SRAM_SCRATCH_LPM_START;
>> if ((pmctrl_val & IO_ISO_STATUS) == IO_ISO_STATUS) {
>> + lpm_scratch->wake_src = LPM_WAKE_SOURCE_MAIN_IO;
>> clear_isolation();
>> gd_set_k3_resuming(K3_RESUME_STATE_RESUMING);
>> debug("Resuming from IO_DDR mode\n");
>> @@ -520,6 +526,7 @@ bool j7xx_board_is_resuming(void)
>> if (pmic_reg_read(pmica, K3_LPM_SCRATCH_PAD_REG) ==
>> K3_LPM_MAGIC_SUSPEND) {
>> debug("%s: board is resuming\n", __func__);
>> + lpm_scratch->wake_src = LPM_WAKE_SOURCE_PMIC_GPIO;
>> gd_set_k3_resuming(K3_RESUME_STATE_RESUMING);
>> /* clean magic suspend */
>> @@ -527,6 +534,8 @@ bool j7xx_board_is_resuming(void)
>> printf("Failed to clean magic value for suspend
>> detection in PMICA\n");
>> } else {
>> debug("%s: board is booting (no resume detected)\n", __func__);
>> + lpm_scratch->wake_src = 0;
>> + lpm_scratch->reserved = 0;
>> gd_set_k3_resuming(K3_RESUME_STATE_BOOTING);
>> }
>> end:
>> diff --git a/board/ti/j784s4/evm.c b/board/ti/j784s4/evm.c
>> index eef56556a33c..b94ec7f3653b 100644
>> --- a/board/ti/j784s4/evm.c
>> +++ b/board/ti/j784s4/evm.c
>> @@ -68,6 +68,9 @@ int board_late_init(void)
>> #if (IS_ENABLED(CONFIG_SPL_BUILD) &&
>> (IS_ENABLED(CONFIG_TARGET_J784S4_R5_EVM) || \
>> IS_ENABLED(CONFIG_TARGET_J742S2_R5_EVM)))
>> +#define LPM_WAKE_SOURCE_PMIC_GPIO 0x91
>> +#define LPM_WAKE_SOURCE_MCU_IO 0x81
>> +
>> static void clear_isolation(void)
>> {
>> int ret;
>> @@ -93,12 +96,15 @@ bool j7xx_board_is_resuming(void)
>> {
>> struct udevice *pmic;
>> u32 pmctrl_val = readl(WKUP_CTRL_MMR0_BASE + PMCTRL_IO_0);
>> + struct lpm_scratch_space *lpm_scratch;
>> int err;
>> if (gd_k3_resuming() != K3_RESUME_STATE_UNKNOWN)
>> goto end;
>> + lpm_scratch = (struct lpm_scratch_space *)TI_SRAM_SCRATCH_LPM_START;
>> if ((pmctrl_val & IO_ISO_STATUS) == IO_ISO_STATUS) {
>> + lpm_scratch->wake_src = LPM_WAKE_SOURCE_MCU_IO;
>> clear_isolation();
>> gd_set_k3_resuming(K3_RESUME_STATE_RESUMING);
>> debug("board is resuming from IO_DDR mode\n");
>> @@ -115,6 +121,7 @@ bool j7xx_board_is_resuming(void)
>> if (pmic_reg_read(pmic, K3_LPM_SCRATCH_PAD_REG) ==
>> K3_LPM_MAGIC_SUSPEND) {
>> debug("%s: board is resuming\n", __func__);
>> + lpm_scratch->wake_src = LPM_WAKE_SOURCE_PMIC_GPIO;
>> gd_set_k3_resuming(K3_RESUME_STATE_RESUMING);
>> /* clean magic suspend */
>> @@ -122,6 +129,8 @@ bool j7xx_board_is_resuming(void)
>> printf("Failed to clean magic value for suspend
>> detection in PMIC\n");
>> } else {
>> debug("%s: board is booting (no resume detected)\n", __func__);
>> + lpm_scratch->wake_src = 0;
>> + lpm_scratch->reserved = 0;
>> gd_set_k3_resuming(K3_RESUME_STATE_BOOTING);
>> }
>> end:
>
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