[PATCH v3 0/3] m68k: coldfire: Add RNG support and const qualifiers for MCF54418

[PATCH v3 0/3] m68k: coldfire: Add RNG support and const qualifiers for MCF54418

[Jean-Michel Hautbois]

This series adds support for the MCF54418 hardware random number generator
(RNGB) and improves type safety for platform device resources.

The MCF54418 contains an RNGB hardware block compatible with the imx-rngc
driver. This series enables its use by:
- Adding platform device registration for the RNG hardware
- Enabling the clock at platform initialization
- Making the imx-rngc driver compatible with Coldfire's always-on clock
model using devm_clk_get_optional()

Additionally, following Frank Li's suggestion, all static resource array
in arch/m68k/coldfire/device.c are marked const, moving them to read-only
memory and aligning with kernel API expectations.

Testing on DLC Next board shows:
- Hardware RNG throughput: 26 MB/s
- FIPS 140-2 quality: 0.2% failure rate (rng-tools)
- Boot time improvement: CRNG initialization 7 seconds faster

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
Changes in v3:
- Depend on COLDFIRE is enough
- Split the clock change in a dedicated commit
- Link to v2: https://lore.kernel.org/r/20251107-b4-m5441x-add-rng-support-v2-0-f91d685832b9@yoseli.org

Changes in v2:
- Split const qualifier changes into a separate patch as suggested by
Frank Li
- Mark all resource arrays (including RNG) as const in device.c
- No functional changes to RNG implementation

---
Jean-Michel Hautbois (3):
      m68k: coldfire: Mark platform device resource arrays as const
      hwrng: imx-rngc: Use optional clock
      m68k: coldfire: Add RNG support for MCF54418

 arch/m68k/coldfire/device.c       | 52 ++++++++++++++++++++++++++++++---------
 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 |  9 ++++++-
 5 files changed, 60 insertions(+), 15 deletions(-)
---
base-commit: ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
change-id: 20251107-b4-m5441x-add-rng-support-0fdb8d40210a

Best regards,
-- 
Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

[PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const

[Jean-Michel Hautbois]

Add 'const' qualifier to all static resource arrays in device.c.
These arrays are never modified at runtime, they are only read by
platform device registration functions.

Suggested-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
 arch/m68k/coldfire/device.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
index b6958ec2a220cf91a78a14fc7fa18749451412f7..20adba27a687029ef53249bad71b342d563d612b 100644
--- a/arch/m68k/coldfire/device.c
+++ b/arch/m68k/coldfire/device.c
@@ -111,7 +111,7 @@ static struct fec_platform_data fec_pdata = {
  *	block. It is Freescale's own hardware block. Some ColdFires
  *	have 2 of these.
  */
-static struct resource mcf_fec0_resources[] = {
+static const struct resource mcf_fec0_resources[] = {
 	{
 		.start		= MCFFEC_BASE0,
 		.end		= MCFFEC_BASE0 + MCFFEC_SIZE0 - 1,
@@ -148,7 +148,7 @@ static struct platform_device mcf_fec0 = {
 #endif /* MCFFEC_BASE0 */
 
 #ifdef MCFFEC_BASE1
-static struct resource mcf_fec1_resources[] = {
+static const struct resource mcf_fec1_resources[] = {
 	{
 		.start		= MCFFEC_BASE1,
 		.end		= MCFFEC_BASE1 + MCFFEC_SIZE1 - 1,
@@ -189,7 +189,7 @@ static struct platform_device mcf_fec1 = {
  *	The ColdFire QSPI module is an SPI protocol hardware block used
  *	on a number of different ColdFire CPUs.
  */
-static struct resource mcf_qspi_resources[] = {
+static const struct resource mcf_qspi_resources[] = {
 	{
 		.start		= MCFQSPI_BASE,
 		.end		= MCFQSPI_BASE + MCFQSPI_SIZE - 1,
@@ -340,7 +340,7 @@ static struct platform_device mcf_qspi = {
 #endif /* IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI) */
 
 #if IS_ENABLED(CONFIG_I2C_IMX)
-static struct resource mcf_i2c0_resources[] = {
+static const struct resource mcf_i2c0_resources[] = {
 	{
 		.start          = MCFI2C_BASE0,
 		.end            = MCFI2C_BASE0 + MCFI2C_SIZE0 - 1,
@@ -361,7 +361,7 @@ static struct platform_device mcf_i2c0 = {
 };
 #ifdef MCFI2C_BASE1
 
-static struct resource mcf_i2c1_resources[] = {
+static const struct resource mcf_i2c1_resources[] = {
 	{
 		.start          = MCFI2C_BASE1,
 		.end            = MCFI2C_BASE1 + MCFI2C_SIZE1 - 1,
@@ -385,7 +385,7 @@ static struct platform_device mcf_i2c1 = {
 
 #ifdef MCFI2C_BASE2
 
-static struct resource mcf_i2c2_resources[] = {
+static const struct resource mcf_i2c2_resources[] = {
 	{
 		.start          = MCFI2C_BASE2,
 		.end            = MCFI2C_BASE2 + MCFI2C_SIZE2 - 1,
@@ -409,7 +409,7 @@ static struct platform_device mcf_i2c2 = {
 
 #ifdef MCFI2C_BASE3
 
-static struct resource mcf_i2c3_resources[] = {
+static const struct resource mcf_i2c3_resources[] = {
 	{
 		.start          = MCFI2C_BASE3,
 		.end            = MCFI2C_BASE3 + MCFI2C_SIZE3 - 1,
@@ -433,7 +433,7 @@ static struct platform_device mcf_i2c3 = {
 
 #ifdef MCFI2C_BASE4
 
-static struct resource mcf_i2c4_resources[] = {
+static const struct resource mcf_i2c4_resources[] = {
 	{
 		.start          = MCFI2C_BASE4,
 		.end            = MCFI2C_BASE4 + MCFI2C_SIZE4 - 1,
@@ -457,7 +457,7 @@ static struct platform_device mcf_i2c4 = {
 
 #ifdef MCFI2C_BASE5
 
-static struct resource mcf_i2c5_resources[] = {
+static const struct resource mcf_i2c5_resources[] = {
 	{
 		.start          = MCFI2C_BASE5,
 		.end            = MCFI2C_BASE5 + MCFI2C_SIZE5 - 1,
@@ -507,7 +507,7 @@ static struct mcf_edma_platform_data mcf_edma_data = {
 	.slavecnt		= ARRAY_SIZE(mcf_edma_map),
 };
 
-static struct resource mcf_edma_resources[] = {
+static const struct resource mcf_edma_resources[] = {
 	{
 		.start		= MCFEDMA_BASE,
 		.end		= MCFEDMA_BASE + MCFEDMA_SIZE - 1,
@@ -560,7 +560,7 @@ static struct mcf_esdhc_platform_data mcf_esdhc_data = {
 	.cd_type = ESDHC_CD_NONE,
 };
 
-static struct resource mcf_esdhc_resources[] = {
+static const struct resource mcf_esdhc_resources[] = {
 	{
 		.start = MCFSDHC_BASE,
 		.end = MCFSDHC_BASE + MCFSDHC_SIZE - 1,
@@ -590,7 +590,7 @@ static struct flexcan_platform_data mcf5441x_flexcan_info = {
 	.clock_frequency = 120000000,
 };
 
-static struct resource mcf5441x_flexcan0_resource[] = {
+static const struct resource mcf5441x_flexcan0_resource[] = {
 	{
 		.start = MCFFLEXCAN_BASE0,
 		.end = MCFFLEXCAN_BASE0 + MCFFLEXCAN_SIZE,

-- 
2.39.5

[PATCH v3 2/3] hwrng: imx-rngc: Use optional clock

[Jean-Michel Hautbois]

Change devm_clk_get() to devm_clk_get_optional() to support platforms
where the RNG clock is always enabled and not exposed via the clock
framework (such as ColdFire MCF54418).

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
 drivers/char/hw_random/imx-rngc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 241664a9b5d9ac7244f15cbe5d5302ca3787ebea..d6a847e48339b2758c73c95d57a7aa48eb4875e0 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
 	if (IS_ERR(rngc->base))
 		return PTR_ERR(rngc->base);
 
-	rngc->clk = devm_clk_get(&pdev->dev, NULL);
+	rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
 	if (IS_ERR(rngc->clk))
 		return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");
 

-- 
2.39.5

[PATCH v3 3/3] m68k: coldfire: Add RNG support for MCF54418

[Jean-Michel Hautbois]

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.

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(-)

diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
index 20adba27a687029ef53249bad71b342d563d612b..4183929b0b501459da25d1b4cde7d77f19c3dc16 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 const 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 7a25cfc7ac07570ff15da3c55d080a717cf93a06..ab5b006372379294db3b522820de88137bfb7e78 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 f48cf63bd7822fd53c33788128f984585c0c421a..dd64cdfcad3e810254c6854b9de5b6bbeb67b950 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 492a2a61a65be8bd9e46b0a70f3e43703973512e..2f301e43db846c687a38377a164429818137ece2 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 d6a847e48339b2758c73c95d57a7aa48eb4875e0..44f20a05de0a425cb6ff7b2a347b111750ac3702 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);

-- 
2.39.5

Re: [PATCH v3 2/3] hwrng: imx-rngc: Use optional clock

[Frank Li]

On Mon, Nov 24, 2025 at 02:04:07PM +0100, Jean-Michel Hautbois wrote:
> Change devm_clk_get() to devm_clk_get_optional() to support platforms
> where the RNG clock is always enabled and not exposed via the clock
> framework (such as ColdFire MCF54418).
>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> ---


Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/char/hw_random/imx-rngc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> index 241664a9b5d9ac7244f15cbe5d5302ca3787ebea..d6a847e48339b2758c73c95d57a7aa48eb4875e0 100644
> --- a/drivers/char/hw_random/imx-rngc.c
> +++ b/drivers/char/hw_random/imx-rngc.c
> @@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
>  	if (IS_ERR(rngc->base))
>  		return PTR_ERR(rngc->base);
>
> -	rngc->clk = devm_clk_get(&pdev->dev, NULL);
> +	rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
>  	if (IS_ERR(rngc->clk))
>  		return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");
>
>
> --
> 2.39.5
>

Re: [PATCH v3 3/3] m68k: coldfire: Add RNG support for MCF54418

[Frank Li]

On Mon, Nov 24, 2025 at 02:04:08PM +0100, Jean-Michel Hautbois wrote:
> 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.
>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

> 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(-)
>
> diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
> index 20adba27a687029ef53249bad71b342d563d612b..4183929b0b501459da25d1b4cde7d77f19c3dc16 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 const 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 7a25cfc7ac07570ff15da3c55d080a717cf93a06..ab5b006372379294db3b522820de88137bfb7e78 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 f48cf63bd7822fd53c33788128f984585c0c421a..dd64cdfcad3e810254c6854b9de5b6bbeb67b950 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 492a2a61a65be8bd9e46b0a70f3e43703973512e..2f301e43db846c687a38377a164429818137ece2 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 d6a847e48339b2758c73c95d57a7aa48eb4875e0..44f20a05de0a425cb6ff7b2a347b111750ac3702 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);
>
> --
> 2.39.5
>

Re: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const

[kernel test robot]

Hi Jean-Michel,

kernel test robot noticed the following build warnings:

[auto build test WARNING on ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d]

url:    https://github.com/intel-lab-lkp/linux/commits/Jean-Michel-Hautbois/m68k-coldfire-Mark-platform-device-resource-arrays-as-const/20251124-210737
base:   ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
patch link:    https://lore.kernel.org/r/20251124-b4-m5441x-add-rng-support-v3-1-f447251dad27%40yoseli.org
patch subject: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const
config: m68k-allnoconfig (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511250103.RMNoU3xH-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/m68k/coldfire/device.c:141:35: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
     141 |         .resource               = mcf_fec0_resources,
         |                                   ^~~~~~~~~~~~~~~~~~


vim +/const +141 arch/m68k/coldfire/device.c

b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  136  
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  137  static struct platform_device mcf_fec0 = {
bea8bcb12da09b arch/m68k/platform/coldfire/device.c Steven King       2012-06-06  138  	.name			= FEC_NAME,
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  139  	.id			= 0,
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  140  	.num_resources		= ARRAY_SIZE(mcf_fec0_resources),
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24 @141  	.resource		= mcf_fec0_resources,
f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  142  	.dev = {
f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  143  		.dma_mask		= &mcf_fec0.dev.coherent_dma_mask,
f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  144  		.coherent_dma_mask	= DMA_BIT_MASK(32),
f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  145  		.platform_data		= FEC_PDATA,
f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  146  	}
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  147  };
63a24cf8cc330e arch/m68k/coldfire/device.c          Antonio Quartulli 2024-10-29  148  #endif /* MCFFEC_BASE0 */
b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  149  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const

[Jean-Michel Hautbois]

On Tue, Nov 25, 2025 at 01:48:24AM +0800, kernel test robot wrote:
> Hi Jean-Michel,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Jean-Michel-Hautbois/m68k-coldfire-Mark-platform-device-resource-arrays-as-const/20251124-210737
> base:   ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
> patch link:    https://lore.kernel.org/r/20251124-b4-m5441x-add-rng-support-v3-1-f447251dad27%40yoseli.org
> patch subject: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const
> config: m68k-allnoconfig (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/config)
> compiler: m68k-linux-gcc (GCC) 15.1.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202511250103.RMNoU3xH-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
> >> arch/m68k/coldfire/device.c:141:35: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
>      141 |         .resource               = mcf_fec0_resources,
>          |                                   ^~~~~~~~~~~~~~~~~~
> 
> 
> vim +/const +141 arch/m68k/coldfire/device.c

Frank, I mentionned this warning in v2, do you have a suggestion ?

Thanks !
JM

> 
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  136  
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  137  static struct platform_device mcf_fec0 = {
> bea8bcb12da09b arch/m68k/platform/coldfire/device.c Steven King       2012-06-06  138  	.name			= FEC_NAME,
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  139  	.id			= 0,
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  140  	.num_resources		= ARRAY_SIZE(mcf_fec0_resources),
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24 @141  	.resource		= mcf_fec0_resources,
> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  142  	.dev = {
> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  143  		.dma_mask		= &mcf_fec0.dev.coherent_dma_mask,
> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  144  		.coherent_dma_mask	= DMA_BIT_MASK(32),
> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  145  		.platform_data		= FEC_PDATA,
> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  146  	}
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  147  };
> 63a24cf8cc330e arch/m68k/coldfire/device.c          Antonio Quartulli 2024-10-29  148  #endif /* MCFFEC_BASE0 */
> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  149  
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki

Re: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const

[Frank Li]

On Tue, Nov 25, 2025 at 08:53:22AM +0100, Jean-Michel Hautbois wrote:
> On Tue, Nov 25, 2025 at 01:48:24AM +0800, kernel test robot wrote:
> > Hi Jean-Michel,
> >
> > kernel test robot noticed the following build warnings:
> >
> > [auto build test WARNING on ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d]
> >
> > url:    https://github.com/intel-lab-lkp/linux/commits/Jean-Michel-Hautbois/m68k-coldfire-Mark-platform-device-resource-arrays-as-const/20251124-210737
> > base:   ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
> > patch link:    https://lore.kernel.org/r/20251124-b4-m5441x-add-rng-support-v3-1-f447251dad27%40yoseli.org
> > patch subject: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const
> > config: m68k-allnoconfig (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/config)
> > compiler: m68k-linux-gcc (GCC) 15.1.0
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/reproduce)
> >
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202511250103.RMNoU3xH-lkp@intel.com/
> >
> > All warnings (new ones prefixed by >>):
> >
> > >> arch/m68k/coldfire/device.c:141:35: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
> >      141 |         .resource               = mcf_fec0_resources,
> >          |                                   ^~~~~~~~~~~~~~~~~~
> >
> >
> > vim +/const +141 arch/m68k/coldfire/device.c
>
> Frank, I mentionned this warning in v2, do you have a suggestion ?

Maybe defer add const until platform_device change define.

Frank

>
> Thanks !
> JM
>
> >
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  136
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  137  static struct platform_device mcf_fec0 = {
> > bea8bcb12da09b arch/m68k/platform/coldfire/device.c Steven King       2012-06-06  138  	.name			= FEC_NAME,
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  139  	.id			= 0,
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  140  	.num_resources		= ARRAY_SIZE(mcf_fec0_resources),
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24 @141  	.resource		= mcf_fec0_resources,
> > f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  142  	.dev = {
> > f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  143  		.dma_mask		= &mcf_fec0.dev.coherent_dma_mask,
> > f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  144  		.coherent_dma_mask	= DMA_BIT_MASK(32),
> > f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  145  		.platform_data		= FEC_PDATA,
> > f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  146  	}
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  147  };
> > 63a24cf8cc330e arch/m68k/coldfire/device.c          Antonio Quartulli 2024-10-29  148  #endif /* MCFFEC_BASE0 */
> > b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  149
> >
> > --
> > 0-DAY CI Kernel Test Service
> > https://github.com/intel/lkp-tests/wiki
>

Re: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const

[Greg Ungerer]

Hi Jean-Michel,

On 25/11/25 17:53, Jean-Michel Hautbois wrote:
> On Tue, Nov 25, 2025 at 01:48:24AM +0800, kernel test robot wrote:
>> Hi Jean-Michel,
>>
>> kernel test robot noticed the following build warnings:
>>
>> [auto build test WARNING on ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d]
>>
>> url:    https://github.com/intel-lab-lkp/linux/commits/Jean-Michel-Hautbois/m68k-coldfire-Mark-platform-device-resource-arrays-as-const/20251124-210737
>> base:   ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
>> patch link:    https://lore.kernel.org/r/20251124-b4-m5441x-add-rng-support-v3-1-f447251dad27%40yoseli.org
>> patch subject: [PATCH v3 1/3] m68k: coldfire: Mark platform device resource arrays as const
>> config: m68k-allnoconfig (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/config)
>> compiler: m68k-linux-gcc (GCC) 15.1.0
>> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250103.RMNoU3xH-lkp@intel.com/reproduce)
>>
>> If you fix the issue in a separate patch/commit (i.e. not just a new version of
>> the same patch/commit), kindly add following tags
>> | Reported-by: kernel test robot <lkp@intel.com>
>> | Closes: https://lore.kernel.org/oe-kbuild-all/202511250103.RMNoU3xH-lkp@intel.com/
>>
>> All warnings (new ones prefixed by >>):
>>
>>>> arch/m68k/coldfire/device.c:141:35: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
>>       141 |         .resource               = mcf_fec0_resources,
>>           |                                   ^~~~~~~~~~~~~~~~~~
>>
>>
>> vim +/const +141 arch/m68k/coldfire/device.c
> 
> Frank, I mentionned this warning in v2, do you have a suggestion ?

FWIW, I looked at other similar use cases - that is platform drivers specifying
constant resources like this - and it seems they mostly do not use const for
them. There is quite a few cases throughout superh and arm architecture code.

Regards
Greg



> Thanks !
> JM
> 
>>
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  136
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  137  static struct platform_device mcf_fec0 = {
>> bea8bcb12da09b arch/m68k/platform/coldfire/device.c Steven King       2012-06-06  138  	.name			= FEC_NAME,
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  139  	.id			= 0,
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  140  	.num_resources		= ARRAY_SIZE(mcf_fec0_resources),
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24 @141  	.resource		= mcf_fec0_resources,
>> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  142  	.dev = {
>> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  143  		.dma_mask		= &mcf_fec0.dev.coherent_dma_mask,
>> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  144  		.coherent_dma_mask	= DMA_BIT_MASK(32),
>> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  145  		.platform_data		= FEC_PDATA,
>> f61e64310b7573 arch/m68k/coldfire/device.c          Greg Ungerer      2018-03-28  146  	}
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  147  };
>> 63a24cf8cc330e arch/m68k/coldfire/device.c          Antonio Quartulli 2024-10-29  148  #endif /* MCFFEC_BASE0 */
>> b7ce7f0d0efc1a arch/m68k/platform/coldfire/device.c Greg Ungerer      2011-12-24  149
>>
>> -- 
>> 0-DAY CI Kernel Test Service
>> https://github.com/intel/lkp-tests/wiki