Re: [PATCH v6 05/13] arm: mach-k3: common: Add CANUART wakeup check helpers

[Kumar, Udit]

On 11/20/2025 9:33 PM, Markus Schneider-Pargmann (TI.com) wrote:

Add dedicated helper functions to check CANUART wake registers and magic
word. This helps determining if we are in a wakeup or if CAN IO
isolation has to be removed.

Also add a helper to detect a low power mode exit/resume.

Tested-by: Anshul Dalal <ansh...@ti.com>
Signed-off-by: Markus Schneider-Pargmann (TI.com) <m...@baylibre.com>
---
  arch/arm/mach-k3/common.c                | 22 ++++++++++++++++++++--
  arch/arm/mach-k3/common.h                |  1 +
  arch/arm/mach-k3/include/mach/hardware.h |  3 +++
  3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c
index 
3cc4e7cba0d1e834280fcce3d1140ca32247d807..7780c7740d5ea2a5dcbb442210ce46e25c5bb61c
 100644
--- a/arch/arm/mach-k3/common.c
+++ b/arch/arm/mach-k3/common.c
@@ -165,13 +165,31 @@ static void wkup_ctrl_remove_can_io_isolation(void)
        writel(0, WKUP_CTRL_MMR0_BASE + WKUP_CTRL_MMR_PMCTRL_IO_GLB);
  }

+static bool wkup_ctrl_canuart_wakeup_active(void)

+{
+       return !!(readl(WKUP_CTRL_MMR0_BASE + WKUP_CTRL_MMR_CANUART_WAKE_STAT1) 
&
+               WKUP_CTRL_MMR_CANUART_WAKE_STAT1_CANUART_IO_MODE);
+}
+
+static bool wkup_ctrl_canuart_magic_word_set(void)
+{
+       return readl(WKUP_CTRL_MMR0_BASE + 
WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT) ==
+               WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT_MW;

+}
+
  void wkup_ctrl_remove_can_io_isolation_if_set(void)
  {
-       if (readl(WKUP_CTRL_MMR0_BASE + WKUP_CTRL_MMR_CANUART_WAKE_STAT1) &
-           WKUP_CTRL_MMR_CANUART_WAKE_STAT1_CANUART_IO_MODE)
+       if (wkup_ctrl_canuart_wakeup_active() && 
!wkup_ctrl_canuart_magic_word_set())
                wkup_ctrl_remove_can_io_isolation();

can this be merged with patch 1/13

  }

+bool wkup_ctrl_is_lpm_exit(void)

+{
+       return IS_ENABLED(CONFIG_K3_IODDR) &&
+               wkup_ctrl_canuart_wakeup_active() &&
+               wkup_ctrl_canuart_magic_word_set();
+}
+
  bool is_rom_loaded_sysfw(struct rom_extended_boot_data *data)
  {
        if (strncmp(data->header, K3_ROM_BOOT_HEADER_MAGIC, 7))
diff --git a/arch/arm/mach-k3/common.h b/arch/arm/mach-k3/common.h
index 
49417679e2ec7210d5c95540f476a5d8ee548617..b7dd52fd1792cb6e3eab5c9f3863f983a8ac08df
 100644
--- a/arch/arm/mach-k3/common.h
+++ b/arch/arm/mach-k3/common.h
@@ -52,6 +52,7 @@ void do_board_detect(void);
  void ti_secure_image_check_binary(void **p_image, size_t *p_size);
  int shutdown_mcu_r5_core1(void);
  void wkup_ctrl_remove_can_io_isolation_if_set(void);
+bool wkup_ctrl_is_lpm_exit(void);

#if (IS_ENABLED(CONFIG_K3_QOS))

  void setup_qos(void);
diff --git a/arch/arm/mach-k3/include/mach/hardware.h 
b/arch/arm/mach-k3/include/mach/hardware.h
index 
d7c759420524faf48ea26c66607c6a899d1321b3..e4e7dd61c0689db11083b81f2e74ba8bea74577e
 100644
--- a/arch/arm/mach-k3/include/mach/hardware.h
+++ b/arch/arm/mach-k3/include/mach/hardware.h
@@ -128,6 +128,9 @@ K3_SOC_ID(j722s, J722S)
  #define WKUP_CTRL_MMR_CANUART_WAKE_STAT1                      0x1830c
  #define WKUP_CTRL_MMR_CANUART_WAKE_STAT1_CANUART_IO_MODE      BIT(0)

+#define WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT 0x18318

+#define WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT_MW            0x555555
+
  #define WKUP_CTRL_MMR_PMCTRL_IO_0                             0x18084
  #define WKUP_CTRL_MMR_PMCTRL_IO_0_ISOCLK_OVRD_0                       BIT(0)
  #define WKUP_CTRL_MMR_PMCTRL_IO_0_ISOOVR_EXTEND_0             BIT(4)