Re: [PATCH] ARM: i.MX: prevent use of imx_cpu_type in PBL

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Sascha,

On 5/26/26 08:35, Sascha Hauer wrote:
> On 2026-05-22 15:48, Ahmad Fatoum wrote:
>> Functions like cpu_is_mx6q internally call cpu_is_mx6() first,
>> which can be evaluated at compile-time if only i.MX6 boards are enabled.
>>
>> This allowed calling cpu_is_mx6q in PBL entry points as long as barebox was
>> compiled for only a single SoC.
>>
>> Since the multi-arch/multi-platform support was added however,
>> cpu_is_mx6 became a runtime check that's never true in PBL, leading all
>> cpu_is_mx* in 32-boards to silently fail at runtime.
>>
>> We have no in-tree boards that are affected by this, so until some
>> out-of-tree user is bothered enough to fix is, acknowledge that this no
>> longer works and turn the silent breakage into a loud compile-time error
>> whenever anything ends up referencing __imx_cpu_type.
> 
> imx_set_cpu_type() has users in PBL:
> 
> arch/arm/mach-imx/atf.c:280:    imx_set_cpu_type(IMX_CPU_IMX8MM);
> arch/arm/mach-imx/atf.c:343:    imx_set_cpu_type(IMX_CPU_IMX8MP);
> arch/arm/mach-imx/atf.c:406:    imx_set_cpu_type(IMX_CPU_IMX8MN);
> arch/arm/mach-imx/atf.c:463:    imx_set_cpu_type(IMX_CPU_IMX8MQ);
> arch/arm/mach-imx/atf.c:492:    imx_set_cpu_type(IMX_CPU_IMX93);
> 
> Also several consumers rely on it in PBL:
> 
> arch/arm/mach-imx/tzasc.c:358:  if (cpu_is_mx8mm() || cpu_is_mx8mn() || cpu_is_mx8mp())
> arch/arm/mach-imx/tzasc.c:365:  if (cpu_is_mx8mn() || cpu_is_mx8mp())
> arch/arm/mach-imx/atf.c:90:     if (cpu_is_mx8mn())
> arch/arm/mach-imx/atf.c:143:    if (cpu_is_mx8mn())
> arch/arm/mach-imx/atf.c:198:    if (!IS_ENABLED(CONFIG_ARCH_IMX_ATF_PASS_BL_PARAMS) || cpu_is_mx8mq()) {

Yes and the definition is still emitted for CONFIG_ARCH_IMX_ATF=y.
The change here onl affects 32-bit i.MX.

Cheers,
Ahmad

> 
> Sascha
> 
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Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |