Re: [PATCH v2] fsl-imx6ul: Instantiate SAI1/2/3 and ASRC as unimplemented devices

[Philippe Mathieu-Daudé]

On 8/10/21 6:03 PM, Guenter Roeck wrote:
> Instantiate SAI1/2/3 and ASRC as unimplemented devices to avoid random
> Linux kernel crashes, such as
> 
> Unhandled fault: external abort on non-linefetch (0x808) at 0xd1580010^M
> pgd = (ptrval)^M
> [d1580010] *pgd=8231b811, *pte=02034653, *ppte=02034453^M
> Internal error: : 808 [#1] SMP ARM^M
> ...
> [<c095e974>] (regmap_mmio_write32le) from [<c095eb48>] 
> (regmap_mmio_write+0x3c/0x54)^M
> [<c095eb48>] (regmap_mmio_write) from [<c09580f4>] 
> (_regmap_write+0x4c/0x1f0)^M
> [<c09580f4>] (_regmap_write) from [<c095837c>] 
> (_regmap_update_bits+0xe4/0xec)^M
> [<c095837c>] (_regmap_update_bits) from [<c09599b4>] 
> (regmap_update_bits_base+0x50/0x74)^M
> [<c09599b4>] (regmap_update_bits_base) from [<c0d3e9e4>] 
> (fsl_asrc_runtime_resume+0x1e4/0x21c)^M
> [<c0d3e9e4>] (fsl_asrc_runtime_resume) from [<c0942464>] 
> (__rpm_callback+0x3c/0x108)^M
> [<c0942464>] (__rpm_callback) from [<c0942590>] (rpm_callback+0x60/0x64)^M
> [<c0942590>] (rpm_callback) from [<c0942b60>] (rpm_resume+0x5cc/0x808)^M
> [<c0942b60>] (rpm_resume) from [<c0942dfc>] (__pm_runtime_resume+0x60/0xa0)^M
> [<c0942dfc>] (__pm_runtime_resume) from [<c0d3ecc4>] 
> (fsl_asrc_probe+0x2a8/0x708)^M
> [<c0d3ecc4>] (fsl_asrc_probe) from [<c0935b08>] (platform_probe+0x58/0xb8)^M
> [<c0935b08>] (platform_probe) from [<c0933264>] 
> (really_probe.part.0+0x9c/0x334)^M
> [<c0933264>] (really_probe.part.0) from [<c093359c>] 
> (__driver_probe_device+0xa0/0x138)^M
> [<c093359c>] (__driver_probe_device) from [<c0933664>] 
> (driver_probe_device+0x30/0xc8)^M
> [<c0933664>] (driver_probe_device) from [<c0933c88>] 
> (__driver_attach+0x90/0x130)^M
> [<c0933c88>] (__driver_attach) from [<c0931060>] 
> (bus_for_each_dev+0x78/0xb8)^M
> [<c0931060>] (bus_for_each_dev) from [<c093254c>] 
> (bus_add_driver+0xf0/0x1d8)^M
> [<c093254c>] (bus_add_driver) from [<c0934a30>] (driver_register+0x88/0x118)^M
> [<c0934a30>] (driver_register) from [<c01022c0>] 
> (do_one_initcall+0x7c/0x3a4)^M
> [<c01022c0>] (do_one_initcall) from [<c1601204>] 
> (kernel_init_freeable+0x198/0x22c)^M
> [<c1601204>] (kernel_init_freeable) from [<c0f5ff2c>] 
> (kernel_init+0x10/0x128)^M
> [<c0f5ff2c>] (kernel_init) from [<c010013c>] (ret_from_fork+0x14/0x38)^M
> 
> or
> 
> Unhandled fault: external abort on non-linefetch (0x808) at 0xd19b0000^M
> pgd = (ptrval)^M
> [d19b0000] *pgd=82711811, *pte=308a0653, *ppte=308a0453^M
> Internal error: : 808 [#1] SMP ARM^M
> ...
> [<c095e974>] (regmap_mmio_write32le) from [<c095eb48>] 
> (regmap_mmio_write+0x3c/0x54)^M
> [<c095eb48>] (regmap_mmio_write) from [<c09580f4>] 
> (_regmap_write+0x4c/0x1f0)^M
> [<c09580f4>] (_regmap_write) from [<c0959b28>] (regmap_write+0x3c/0x60)^M
> [<c0959b28>] (regmap_write) from [<c0d41130>] 
> (fsl_sai_runtime_resume+0x9c/0x1ec)^M
> [<c0d41130>] (fsl_sai_runtime_resume) from [<c0942464>] 
> (__rpm_callback+0x3c/0x108)^M
> [<c0942464>] (__rpm_callback) from [<c0942590>] (rpm_callback+0x60/0x64)^M
> [<c0942590>] (rpm_callback) from [<c0942b60>] (rpm_resume+0x5cc/0x808)^M
> [<c0942b60>] (rpm_resume) from [<c0942dfc>] (__pm_runtime_resume+0x60/0xa0)^M
> [<c0942dfc>] (__pm_runtime_resume) from [<c0d4231c>] 
> (fsl_sai_probe+0x2b8/0x65c)^M
> [<c0d4231c>] (fsl_sai_probe) from [<c0935b08>] (platform_probe+0x58/0xb8)^M
> [<c0935b08>] (platform_probe) from [<c0933264>] 
> (really_probe.part.0+0x9c/0x334)^M
> [<c0933264>] (really_probe.part.0) from [<c093359c>] 
> (__driver_probe_device+0xa0/0x138)^M
> [<c093359c>] (__driver_probe_device) from [<c0933664>] 
> (driver_probe_device+0x30/0xc8)^M
> [<c0933664>] (driver_probe_device) from [<c0933c88>] 
> (__driver_attach+0x90/0x130)^M
> [<c0933c88>] (__driver_attach) from [<c0931060>] 
> (bus_for_each_dev+0x78/0xb8)^M
> [<c0931060>] (bus_for_each_dev) from [<c093254c>] 
> (bus_add_driver+0xf0/0x1d8)^M
> [<c093254c>] (bus_add_driver) from [<c0934a30>] (driver_register+0x88/0x118)^M
> [<c0934a30>] (driver_register) from [<c01022c0>] 
> (do_one_initcall+0x7c/0x3a4)^M
> [<c01022c0>] (do_one_initcall) from [<c1601204>] 
> (kernel_init_freeable+0x198/0x22c)^M
> [<c1601204>] (kernel_init_freeable) from [<c0f5ff2c>] 
> (kernel_init+0x10/0x128)^M
> [<c0f5ff2c>] (kernel_init) from [<c010013c>] (ret_from_fork+0x14/0x38)^M
> 
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> v2: Updated description to include tracebacks and to use the term 
> 'instantiate'
>     Added inline comments describing devices in more detail

Thank you!

Peter you might want to s/^M// when queueing ;)

>     Added Philippe's Reviewed-by: tag
> 
>  hw/arm/fsl-imx6ul.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/hw/arm/fsl-imx6ul.c b/hw/arm/fsl-imx6ul.c
> index e0128d7316..1d1a708dd9 100644
> --- a/hw/arm/fsl-imx6ul.c
> +++ b/hw/arm/fsl-imx6ul.c
> @@ -534,6 +534,13 @@ static void fsl_imx6ul_realize(DeviceState *dev, Error 
> **errp)
>       */
>      create_unimplemented_device("sdma", FSL_IMX6UL_SDMA_ADDR, 0x4000);
>  
> +    /*
> +     * SAI (Audio SSI (Synchronous Serial Interface))
> +     */
> +    create_unimplemented_device("sai1", FSL_IMX6UL_SAI1_ADDR, 0x4000);
> +    create_unimplemented_device("sai2", FSL_IMX6UL_SAI2_ADDR, 0x4000);
> +    create_unimplemented_device("sai3", FSL_IMX6UL_SAI3_ADDR, 0x4000);
> +
>      /*
>       * PWM
>       */
> @@ -542,6 +549,11 @@ static void fsl_imx6ul_realize(DeviceState *dev, Error 
> **errp)
>      create_unimplemented_device("pwm3", FSL_IMX6UL_PWM3_ADDR, 0x4000);
>      create_unimplemented_device("pwm4", FSL_IMX6UL_PWM4_ADDR, 0x4000);
>  
> +    /*
> +     * Audio ASRC (asynchronous sample rate converter)
> +     */
> +    create_unimplemented_device("asrc", FSL_IMX6UL_ASRC_ADDR, 0x4000);
> +
>      /*
>       * CAN
>       */
>