Re: [PATCH v4 2/2] m68k: coldfire: Add RNG support for MCF54418

[Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>]

Hi Greg,

Sorry for the very long silence on this one, it fell off my radar...

Le 03/12/2025 à 13:15, Greg Ungerer a écrit :
> Hi Jean-Michel,
> 
> On 26/11/25 17:08, Jean-Michel Hautbois via B4 Relay wrote:
>> From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
>>
>> Add support for the hardware Random Number Generator (RNGB) found on
>> MCF54418 ColdFire processors with clock enabled at platform
>> initialization.
>>
>> The RNGB block is compatible with the imx-rngc driver.
>>
>> Reviewed-by: Frank Li <Frank.Li@nxp.com>
>> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
>> ---
>>   arch/m68k/coldfire/device.c       | 28 ++++++++++++++++++++++++++++
>>   arch/m68k/coldfire/m5441x.c       |  2 +-
>>   arch/m68k/include/asm/m5441xsim.h |  9 +++++++++
>>   drivers/char/hw_random/Kconfig    |  3 ++-
>>   drivers/char/hw_random/imx-rngc.c |  7 +++++++
>>   5 files changed, 47 insertions(+), 2 deletions(-)
> 
> I am happy with the ColdFire arch parts, so from me:
> 
>      Acked-by: Greg Ungerer <gerg@linux-m68k.org>
> 
> I don't mind taking this commit via the m68knommu git tree if the hw_rng
> maintainers are ok with that. Otherwise if you break out the arch/m68k
> parts I can apply those on their own.

I think Herbert acked ?
Do you need another ack ?

Thanks !
JM

> Regards
> Greg
> 
> 
> 
>> diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
>> index b6958ec2a220..9d8f844e319a 100644
>> --- a/arch/m68k/coldfire/device.c
>> +++ b/arch/m68k/coldfire/device.c
>> @@ -622,6 +622,31 @@ static struct platform_device mcf_flexcan0 = {
>>   };
>>   #endif /* MCFFLEXCAN_SIZE */
>> +#ifdef MCF_RNG_BASE
>> +/*
>> + * Random Number Generator (RNG) - only on MCF54418
>> + */
>> +static struct resource mcf_rng_resource[] = {
>> +    {
>> +        .start = MCF_RNG_BASE,
>> +        .end   = MCF_RNG_BASE + MCF_RNG_SIZE - 1,
>> +        .flags = IORESOURCE_MEM,
>> +    },
>> +    {
>> +        .start = MCF_IRQ_RNG,
>> +        .end   = MCF_IRQ_RNG,
>> +        .flags = IORESOURCE_IRQ,
>> +    },
>> +};
>> +
>> +static struct platform_device mcf_rng = {
>> +    .name           = "imx-rngc",
>> +    .id             = -1,
>> +    .num_resources  = ARRAY_SIZE(mcf_rng_resource),
>> +    .resource       = mcf_rng_resource,
>> +};
>> +#endif /* MCF_RNG_BASE */
>> +
>>   static struct platform_device *mcf_devices[] __initdata = {
>>       &mcf_uart,
>>   #ifdef MCFFEC_BASE0
>> @@ -660,6 +685,9 @@ static struct platform_device *mcf_devices[] 
>> __initdata = {
>>   #ifdef MCFFLEXCAN_SIZE
>>       &mcf_flexcan0,
>>   #endif
>> +#ifdef MCF_RNG_BASE
>> +    &mcf_rng,
>> +#endif
>>   };
>>   /*
>> diff --git a/arch/m68k/coldfire/m5441x.c b/arch/m68k/coldfire/m5441x.c
>> index 7a25cfc7ac07..ab5b00637237 100644
>> --- a/arch/m68k/coldfire/m5441x.c
>> +++ b/arch/m68k/coldfire/m5441x.c
>> @@ -158,6 +158,7 @@ static struct clk * const enable_clks[] 
>> __initconst = {
>>       &__clk_0_33, /* pit.1 */
>>       &__clk_0_37, /* eport */
>>       &__clk_0_48, /* pll */
>> +    &__clk_0_49, /* rng */
>>       &__clk_0_51, /* esdhc */
>>       &__clk_1_36, /* CCM/reset module/Power management */
>> @@ -179,7 +180,6 @@ static struct clk * const disable_clks[] 
>> __initconst = {
>>       &__clk_0_44, /* usb otg */
>>       &__clk_0_45, /* usb host */
>>       &__clk_0_47, /* ssi.0 */
>> -    &__clk_0_49, /* rng */
>>       &__clk_0_50, /* ssi.1 */
>>       &__clk_0_53, /* enet-fec */
>>       &__clk_0_54, /* enet-fec */
>> diff --git a/arch/m68k/include/asm/m5441xsim.h b/arch/m68k/include/ 
>> asm/m5441xsim.h
>> index f48cf63bd782..dd64cdfcad3e 100644
>> --- a/arch/m68k/include/asm/m5441xsim.h
>> +++ b/arch/m68k/include/asm/m5441xsim.h
>> @@ -198,6 +198,15 @@
>>   #define MCFRTC_SIZE        (0xfc0a8840 - 0xfc0a8000)
>>   #define MCF_IRQ_RTC        (MCFINT2_VECBASE + MCFINT2_RTC)
>> +/*
>> + *  Random Number Generator (RNG) Module.
>> + *  Note: Only present in MCF54418, not in MCF54410/54415/54417
>> + */
>> +#define MCF_RNG_BASE        0xfc0c4000
>> +#define MCF_RNG_SIZE        0x1c
>> +#define MCFINT2_RNG        28
>> +#define MCF_IRQ_RNG        (MCFINT2_VECBASE + MCFINT2_RNG)
>> +
>>   /*
>>    *  GPIO Module.
>>    */
>> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/ 
>> Kconfig
>> index 492a2a61a65b..2f301e43db84 100644
>> --- a/drivers/char/hw_random/Kconfig
>> +++ b/drivers/char/hw_random/Kconfig
>> @@ -270,12 +270,13 @@ config HW_RANDOM_MXC_RNGA
>>   config HW_RANDOM_IMX_RNGC
>>       tristate "Freescale i.MX RNGC Random Number Generator"
>>       depends on HAS_IOMEM
>> -    depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL 
>> || COMPILE_TEST
>> +    depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL 
>> || COLDFIRE || COMPILE_TEST
>>       default HW_RANDOM
>>       help
>>         This driver provides kernel-side support for the Random Number
>>         Generator Version C hardware found on some Freescale i.MX
>>         processors. Version B is also supported by this driver.
>> +      Also supports RNGB on Freescale MCF54418 (Coldfire V4e).
>>         To compile this driver as a module, choose M here: the
>>         module will be called imx-rngc.
>> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/ 
>> hw_random/imx-rngc.c
>> index d6a847e48339..44f20a05de0a 100644
>> --- a/drivers/char/hw_random/imx-rngc.c
>> +++ b/drivers/char/hw_random/imx-rngc.c
>> @@ -353,12 +353,19 @@ static const struct of_device_id 
>> imx_rngc_dt_ids[] = {
>>   };
>>   MODULE_DEVICE_TABLE(of, imx_rngc_dt_ids);
>> +static const struct platform_device_id imx_rngc_devtype[] = {
>> +    { .name = "imx-rngc" },
>> +    { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(platform, imx_rngc_devtype);
>> +
>>   static struct platform_driver imx_rngc_driver = {
>>       .driver = {
>>           .name = KBUILD_MODNAME,
>>           .pm = pm_ptr(&imx_rngc_pm_ops),
>>           .of_match_table = imx_rngc_dt_ids,
>>       },
>> +    .id_table = imx_rngc_devtype,
>>   };
>>   module_platform_driver_probe(imx_rngc_driver, imx_rngc_probe);
>>
>