• Mohan Kumar's avatar
    ASoC: tegra: Fix CBB error during probe() · 6781b962
    Mohan Kumar authored
    When Tegra audio drivers are built as part of the kernel image,
    TIMEOUT_ERR is observed from cbb-fabric. Following is seen on
    Jetson AGX Orin during boot:
    
    [    8.012482] **************************************
    [    8.017423] CPU:0, Error:cbb-fabric, Errmon:2
    [    8.021922]    Error Code            : TIMEOUT_ERR
    [    8.025966]    Overflow              : Multiple TIMEOUT_ERR
    [    8.030644]
    [    8.032175]    Error Code            : TIMEOUT_ERR
    [    8.036217]    MASTER_ID             : CCPLEX
    [    8.039722]    Address               : 0x290a0a8
    [    8.043318]    Cache                 : 0x1 -- Bufferable
    [    8.047630]    Protection            : 0x2 -- Unprivileged, Non-Secure, Data Access
    [    8.054628]    Access_Type           : Write
    
    [    8.106130] WARNING: CPU: 0 PID: 124 at drivers/soc/tegra/cbb/tegra234-cbb.c:604 tegra234_cbb_isr+0x134/0x178
    
    [    8.240602] Call trace:
    [    8.243126]  tegra234_cbb_isr+0x134/0x178
    [    8.247261]  __handle_irq_event_percpu+0x60/0x238
    [    8.252132]  handle_irq_event+0x54/0xb8
    
    These errors happen when MVC device, which is a child of AHUB
    device, tries to access its device registers. This happens as
    part of call tegra210_mvc_reset_vol_settings() in MVC device
    probe().
    
    The root cause of this problem is, the child MVC device gets
    probed before the AHUB clock gets enabled. The AHUB clock is
    enabled in runtime PM resume of parent AHUB device and due to
    the wrong sequence of pm_runtime_enable() in AHUB driver,
    runtime PM resume doesn't happen for AHUB device when MVC makes
    register access.
    
    Fix this by calling pm_runtime_enable() for parent AHUB device
    before of_platform_populate() in AHUB driver. This ensures that
    clock becomes available when MVC makes register access.
    
    Fixes: 16e1bcc2 ("ASoC: tegra: Add Tegra210 based AHUB driver")
    Signed-off-by: default avatarMohan Kumar <mkumard@nvidia.com>
    Signed-off-by: default avatarRitu Chaudhary <rituc@nvidia.com>
    Signed-off-by: default avatarSameer Pujar <spujar@nvidia.com>
    Link: https://patch.msgid.link/20240823144342.4123814-3-spujar@nvidia.comSigned-off-by: default avatarMark Brown <broonie@kernel.org>
    6781b962
tegra210_ahub.c 39.6 KB