RE: [PATCH v3 1/4] clk: imx: add i.MX6UL clk driver

[Christoph Niedermaier <cniedermaier@dh-electronics.com>]

Hello, 

From: Michael Trimarchi <michael@amarulasolutions.com>
Sent: Thursday, May 29, 2025 7:10 AM
> Subject: [PATCH v3 1/4] clk: imx: add i.MX6UL clk driver
> 
> Add i.MX6UL clk driver for i.MX6UL CLK driver model usage
> 
> Reviewed-by: Peng Fan <peng.fan@nxp.com>
> Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> 
> ---
> 
> Changes in v3:
> - Add all uarts definition
> - Move OSC on top suggested
> - Drop an invalid clock definition
> - Move some pll before they are referenced
> 
> Changes in v2:
> - None
> 
>  drivers/clk/imx/Kconfig      |   8 +
>  drivers/clk/imx/Makefile     |   1 +
>  drivers/clk/imx/clk-imx6ul.c | 290 +++++++++++++++++++++++++++++++++++
>  3 files changed, 299 insertions(+)
>  create mode 100644 drivers/clk/imx/clk-imx6ul.c
> 
> diff --git a/drivers/clk/imx/Kconfig b/drivers/clk/imx/Kconfig
> index d17a54fb9b3..705d4a8e2ac 100644
> --- a/drivers/clk/imx/Kconfig
> +++ b/drivers/clk/imx/Kconfig
> @@ -14,6 +14,14 @@ config CLK_IMX6Q
>         help
>           This enables DM/DTS support for clock driver in i.MX6Q platforms.
> 
> +config CLK_IMX6UL
> +       bool "Clock support for i.MXUL"

I'm sorry, I haven't seen that before, but I think it should be "i.MX6UL"
and not "i.MXUL".

> +       depends on ARCH_MX6
> +       select CLK
> +       select CLK_CCF
> +       help
> +         This enables DM/DTS support for clock driver in i.MX6UL platforms.
> +
>  config CLK_IMX8
>         bool "Clock support for i.MX8"
>         depends on ARCH_IMX8
> diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
> index a89ee7acb12..b10221a195c 100644
> --- a/drivers/clk/imx/Makefile
> +++ b/drivers/clk/imx/Makefile
> @@ -4,6 +4,7 @@
> 
>  obj-$(CONFIG_$(PHASE_)CLK_CCF) += clk-gate2.o clk-pllv3.o clk-pfd.o
>  obj-$(CONFIG_$(PHASE_)CLK_IMX6Q) += clk-imx6q.o
> +obj-$(CONFIG_$(PHASE_)CLK_IMX6UL) += clk-imx6ul.o
>  obj-$(CONFIG_CLK_IMX8) += clk-imx8.o
> 
>  ifdef CONFIG_CLK_IMX8
> diff --git a/drivers/clk/imx/clk-imx6ul.c b/drivers/clk/imx/clk-imx6ul.c
> new file mode 100644
> index 00000000000..bd52c1d487c
> --- /dev/null
> +++ b/drivers/clk/imx/clk-imx6ul.c
> @@ -0,0 +1,290 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2025 Amarula Solutions Software Engineering
> + * Michael Trimarchi, Amarula Solutions Software Engineering,
> michael@amarulasolutions.com
> + */
> +
> +#include <clk-uclass.h>
> +#include <dm.h>
> +#include <log.h>
> +#include <asm/arch/clock.h>
> +#include <asm/arch/imx-regs.h>
> +#include <dt-bindings/clock/imx6ul-clock.h>
> +
> +#include "clk.h"
> +
> +static int imx6ul_clk_request(struct clk *clk)
> +{
> +       debug("%s: request clk id %ld\n", __func__, clk->id);
> +
> +       if (clk->id < IMX6UL_CLK_DUMMY || clk->id >= IMX6UL_CLK_END) {
> +               printf("%s: Invalid clk ID #%lu\n", __func__, clk->id);
> +               return -EINVAL;
> +       }
> +
> +       return 0;
> +}
> +
> +static struct clk_ops imx6ul_clk_ops = {
> +       .request = imx6ul_clk_request,
> +       .set_rate = ccf_clk_set_rate,
> +       .get_rate = ccf_clk_get_rate,
> +       .enable = ccf_clk_enable,
> +       .disable = ccf_clk_disable,
> +};
> +
> +static const char *const pll_bypass_src_sels[] = { "osc", "dummy", };
> +static const char *const pll3_bypass_sels[] = { "pll3", "pll3_bypass_src", };
> +static const char *const bch_sels[] = { "pll2_pfd2_396m", "pll2_pfd0_352m", };
> +static const char *const gpmi_sels[] = { "pll2_pfd2_396m", "pll2_pfd0_352m", };
> +
> +static const char *const enfc_sels[] = { "pll2_pfd0_352m", "pll2_bus", "pll3_usb_otg",
> "pll2_pfd2_396m",
> +                                        "pll3_pfd3_454m", "dummy", "dummy", "dummy", };
> +static const char *const usdhc_sels[] = { "pll2_pfd2_396m", "pll2_pfd0_352m", };
> +static const char *const periph_sels[] = { "periph_pre", "periph_clk2", };
> +static const char *const periph2_pre_sels[] = { "pll2_bus", "pll2_pfd2_396m",
> "pll2_pfd0_352m",
> +                                               "pll4_audio_div", };
> +static const char *const periph_clk2_sels[] = { "pll3_usb_otg", "osc", "pll2_bypass_src",
> };
> +static const char *const periph2_clk2_sels[] = { "pll3_usb_otg", "osc", };
> +static const char *const perclk_sels[] = { "ipg", "osc", };
> +
> +static const char *const periph_pre_sels[] = { "pll2_bus", "pll2_pfd2_396m",
> "pll2_pfd0_352m",
> +                                              "pll2_198m", };
> +static const char *const uart_sels[] = { "pll3_80m", "osc", };
> +static const char *const ecspi_sels[] = { "pll3_60m", "osc", };
> +
> +static int imx6ul_clk_probe(struct udevice *dev)
> +{
> +       struct clk osc_clk;
> +       void *base;
> +       int ret;
> +
> +       /* Anatop clocks */
> +       base = (void *)ANATOP_BASE_ADDR;
> +
> +       clk_dm(IMX6UL_CLK_DUMMY, clk_register_fixed_rate(NULL, "dummy", 0));
> +
> +       ret = clk_get_by_name(dev, "osc", &osc_clk);
> +       if (ret)
> +               return ret;
> +
> +       clk_dm(IMX6UL_CLK_OSC, dev_get_clk_ptr(osc_clk.dev));
> +
> +       clk_dm(IMX6UL_CLK_PLL2,
> +              imx_clk_pllv3(dev, IMX_PLLV3_GENERIC, "pll2_bus", "osc",
> +                            base + 0x30, 0x1));
> +       clk_dm(IMX6UL_CLK_PLL3,
> +              imx_clk_pllv3(dev, IMX_PLLV3_USB, "pll3", "osc",
> +                            base + 0x10, 0x3));
> +       clk_dm(IMX6UL_PLL3_BYPASS_SRC,
> +              imx_clk_mux(dev, "pll3_bypass_src", base + 0x10, 14, 1,
> +                          pll_bypass_src_sels,
> +                          ARRAY_SIZE(pll_bypass_src_sels)));
> +       clk_dm(IMX6UL_PLL3_BYPASS,
> +              imx_clk_mux_flags(dev, "pll3_bypass", base + 0x10, 16, 1,
> +                                pll3_bypass_sels, ARRAY_SIZE(pll3_bypass_sels),
> +                                CLK_SET_RATE_PARENT));
> +       clk_dm(IMX6UL_CLK_PLL3_USB_OTG,
> +              imx_clk_gate(dev, "pll3_usb_otg", "pll3_bypass", base + 0x10,
> +                           13));
> +       clk_dm(IMX6UL_CLK_PLL3_80M,
> +              imx_clk_fixed_factor(dev, "pll3_80m", "pll3_usb_otg", 1, 6));
> +       clk_dm(IMX6UL_CLK_PLL3_60M,
> +              imx_clk_fixed_factor(dev, "pll3_60m", "pll3_usb_otg", 1, 8));
> +       clk_dm(IMX6UL_CLK_PLL2_PFD0,
> +              imx_clk_pfd("pll2_pfd0_352m", "pll2_bus", base + 0x100, 0));
> +       clk_dm(IMX6UL_CLK_PLL2_PFD1,
> +              imx_clk_pfd("pll2_pfd1_594m", "pll2_bus", base + 0x100, 1));
> +       clk_dm(IMX6UL_CLK_PLL2_PFD2,
> +              imx_clk_pfd("pll2_pfd2_396m", "pll2_bus", base + 0x100, 2));
> +       clk_dm(IMX6UL_CLK_PLL2_PFD3,
> +              imx_clk_pfd("pll2_pfd3_396m", "pll2_bus", base + 0x100, 3));
> +       clk_dm(IMX6UL_CLK_PLL6,
> +              imx_clk_pllv3(dev, IMX_PLLV3_ENET, "pll6", "osc", base + 0xe0,
> +                            0x3));
> +       clk_dm(IMX6UL_CLK_PLL6_ENET,
> +              imx_clk_gate(dev, "pll6_enet", "pll6", base + 0xe0, 13));
> +
> +       /* CCM clocks */
> +       base = dev_read_addr_ptr(dev);
> +       if (!base)
> +               return -EINVAL;
> +
> +       clk_dm(IMX6UL_CLK_GPMI_SEL,
> +              imx_clk_mux(dev, "gpmi_sel", base + 0x1c, 19, 1, gpmi_sels,
> +                          ARRAY_SIZE(gpmi_sels)));
> +       clk_dm(IMX6UL_CLK_BCH_SEL,
> +              imx_clk_mux(dev, "bch_sel", base + 0x1c, 18, 1, bch_sels,
> +                          ARRAY_SIZE(bch_sels)));
> +       clk_dm(IMX6UL_CLK_USDHC1_SEL,
> +              imx_clk_mux(dev, "usdhc1_sel", base + 0x1c, 16, 1, usdhc_sels,
> +                          ARRAY_SIZE(usdhc_sels)));
> +       clk_dm(IMX6UL_CLK_USDHC2_SEL,
> +              imx_clk_mux(dev, "usdhc2_sel", base + 0x1c, 17, 1, usdhc_sels,
> +                          ARRAY_SIZE(usdhc_sels)));
> +       clk_dm(IMX6UL_CLK_ECSPI_SEL,
> +              imx_clk_mux(dev, "ecspi_sel", base + 0x38, 18, 1, ecspi_sels,
> +                          ARRAY_SIZE(ecspi_sels)));
> +       clk_dm(IMX6UL_CLK_UART_SEL,
> +              imx_clk_mux(dev, "uart_sel", base + 0x24, 6, 1, uart_sels,
> +                          ARRAY_SIZE(uart_sels)));
> +       clk_dm(IMX6UL_CLK_ENFC_SEL,
> +              imx_clk_mux(dev, "enfc_sel", base + 0x2c, 15, 3, enfc_sels,
> +                          ARRAY_SIZE(enfc_sels)));
> +       clk_dm(IMX6UL_CLK_PERCLK_SEL,
> +              imx_clk_mux(dev, "perclk_sel", base + 0x1c, 6, 1, perclk_sels,
> +                          ARRAY_SIZE(perclk_sels)));
> +       clk_dm(IMX6UL_CLK_PERIPH_PRE,
> +              imx_clk_mux(dev, "periph_pre", base + 0x18, 18, 2,
> +                          periph_pre_sels, ARRAY_SIZE(periph_pre_sels)));
> +       clk_dm(IMX6UL_CLK_PERIPH2_PRE,
> +              imx_clk_mux(dev, "periph2_pre", base + 0x18, 21, 2,
> +                          periph2_pre_sels, ARRAY_SIZE(periph2_pre_sels)));
> +       clk_dm(IMX6UL_CLK_PERIPH_CLK2_SEL,
> +              imx_clk_mux(dev, "periph_clk2_sel", base + 0x18, 12, 2,
> +                          periph_clk2_sels, ARRAY_SIZE(periph_clk2_sels)));
> +       clk_dm(IMX6UL_CLK_PERIPH2_CLK2_SEL,
> +              imx_clk_mux(dev, "periph2_clk2_sel", base + 0x18, 20, 1,
> +                          periph2_clk2_sels, ARRAY_SIZE(periph2_clk2_sels)));
> +       clk_dm(IMX6UL_CLK_PERIPH,
> +              imx_clk_busy_mux(dev, "periph", base + 0x14, 25, 1, base + 0x48,
> +                               5, periph_sels, ARRAY_SIZE(periph_sels)));
> +       clk_dm(IMX6UL_CLK_AHB,
> +              imx_clk_busy_divider(dev, "ahb", "periph", base + 0x14, 10, 3,
> +                                   base + 0x48, 1));
> +       clk_dm(IMX6UL_CLK_PERIPH_CLK2,
> +              imx_clk_divider(dev, "periph_clk2", "periph_clk2_sel",
> +                              base + 0x14, 27, 3));
> +       clk_dm(IMX6UL_CLK_PERIPH2_CLK2,
> +              imx_clk_divider(dev, "periph2_clk2", "periph2_clk2_sel",
> +                              base + 0x14, 0, 3));
> +       clk_dm(IMX6UL_CLK_IPG,
> +              imx_clk_divider(dev, "ipg", "ahb", base + 0x14, 8, 2));
> +       clk_dm(IMX6UL_CLK_ENFC_PRED,
> +              imx_clk_divider(dev, "enfc_pred", "enfc_sel", base + 0x2c, 18,
> +                              3));
> +       clk_dm(IMX6UL_CLK_ENFC_PODF,
> +              imx_clk_divider(dev, "enfc_podf", "enfc_pred", base + 0x2c, 21,
> +                              6));
> +       clk_dm(IMX6UL_CLK_GPMI_PODF,
> +              imx_clk_divider(dev, "gpmi_podf", "gpmi_sel", base + 0x24, 22,
> +                              3));
> +       clk_dm(IMX6UL_CLK_BCH_PODF,
> +              imx_clk_divider(dev, "bch_podf", "bch_sel", base + 0x24, 19, 3));
> +       clk_dm(IMX6UL_CLK_PERCLK,
> +              imx_clk_divider(dev, "perclk", "perclk_sel", base + 0x1c, 0, 6));
> +       clk_dm(IMX6UL_CLK_UART_PODF,
> +              imx_clk_divider(dev, "uart_podf", "uart_sel", base + 0x24, 0,
> +                              6));
> +       clk_dm(IMX6UL_CLK_USDHC1_PODF,
> +              imx_clk_divider(dev, "usdhc1_podf", "usdhc1_sel", base + 0x24,
> +                              11, 3));
> +       clk_dm(IMX6UL_CLK_USDHC2_PODF,
> +              imx_clk_divider(dev, "usdhc2_podf", "usdhc2_sel", base + 0x24,
> +                              16, 3));
> +       clk_dm(IMX6UL_CLK_ECSPI_PODF,
> +              imx_clk_divider(dev, "ecspi_podf", "ecspi_sel", base + 0x38, 19,
> +                              6));
> +
> +       clk_dm(IMX6UL_CLK_APBHDMA,
> +              imx_clk_gate2(dev, "apbh_dma", "bch_podf", base + 0x68, 4));
> +       clk_dm(IMX6UL_CLK_ECSPI1,
> +              imx_clk_gate2(dev, "ecspi1", "ecspi_podf", base + 0x6c, 0));
> +       clk_dm(IMX6UL_CLK_ECSPI2,
> +              imx_clk_gate2(dev, "ecspi2", "ecspi_podf", base + 0x6c, 2));
> +       clk_dm(IMX6UL_CLK_ECSPI3,
> +              imx_clk_gate2(dev, "ecspi3", "ecspi_podf", base + 0x6c, 4));
> +       clk_dm(IMX6UL_CLK_ECSPI4,
> +              imx_clk_gate2(dev, "ecspi4", "ecspi_podf", base + 0x6c, 6));
> +
> +       clk_dm(IMX6UL_CLK_USBOH3,
> +              imx_clk_gate2(dev, "usboh3", "ipg", base + 0x80, 0));
> +       clk_dm(IMX6UL_CLK_USDHC1,
> +              imx_clk_gate2(dev, "usdhc1", "usdhc1_podf", base + 0x80, 2));
> +       clk_dm(IMX6UL_CLK_USDHC2,
> +              imx_clk_gate2(dev, "usdhc2", "usdhc2_podf", base + 0x80, 4));
> +
> +       clk_dm(IMX6UL_CLK_UART1_IPG,
> +              imx_clk_gate2(dev, "uart1_ipg", "ipg", base + 0x7c, 24));
> +       clk_dm(IMX6UL_CLK_UART1_SERIAL,
> +              imx_clk_gate2(dev, "uart1_serial", "uart_podf", base + 0x7c, 24));
> +       clk_dm(IMX6UL_CLK_UART2_IPG,
> +              imx_clk_gate2(dev, "uart2_ipg", "ipg", base + 0x68, 28));
> +       clk_dm(IMX6UL_CLK_UART2_SERIAL,
> +              imx_clk_gate2(dev, "uart2_serial", "uart_podf", base + 0x68, 28));
> +       clk_dm(IMX6UL_CLK_UART3_IPG,
> +              imx_clk_gate2(dev, "uart3_ipg", "ipg", base + 0x6c, 10));
> +       clk_dm(IMX6UL_CLK_UART3_SERIAL,
> +              imx_clk_gate2(dev, "uart3_serial", "uart_podf", base + 0x6c, 10));
> +       clk_dm(IMX6UL_CLK_UART4_IPG,
> +              imx_clk_gate2(dev, "uart4_ipg", "ipg", base + 0x6c, 24));
> +       clk_dm(IMX6UL_CLK_UART4_SERIAL,
> +              imx_clk_gate2(dev, "uart4_serial", "uart_podf", base + 0x6c, 24));
> +       clk_dm(IMX6UL_CLK_UART5_IPG,
> +              imx_clk_gate2(dev, "uart5_ipg", "ipg", base + 0x74, 2));
> +       clk_dm(IMX6UL_CLK_UART5_SERIAL,
> +              imx_clk_gate2(dev, "uart5_serial", "uart_podf", base + 0x74, 2));
> +       clk_dm(IMX6UL_CLK_UART6_IPG,
> +              imx_clk_gate2(dev, "uart6_ipg", "ipg", base + 0x74, 6));
> +       clk_dm(IMX6UL_CLK_UART6_SERIAL,
> +              imx_clk_gate2(dev, "uart6_serial", "uart_podf", base + 0x74, 6));
> +       clk_dm(IMX6UL_CLK_UART7_IPG,
> +              imx_clk_gate2(dev, "uart7_ipg", "ipg", base + 0x7c, 26));
> +       clk_dm(IMX6UL_CLK_UART7_SERIAL,
> +              imx_clk_gate2(dev, "uart7_serial", "uart_podf", base + 0x7c, 26));
> +       clk_dm(IMX6UL_CLK_UART8_IPG,
> +              imx_clk_gate2(dev, "uart8_ipg", "ipg", base + 0x80, 14));
> +       clk_dm(IMX6UL_CLK_UART8_SERIAL,
> +              imx_clk_gate2(dev, "uart8_serial", "uart_podf", base + 0x80, 14));

Thanks for adding the UARTs. Now my Console is working.

> +
> +#if CONFIG_IS_ENABLED(NAND_MXS)
> +       clk_dm(IMX6UL_CLK_PER_BCH,
> +              imx_clk_gate2(dev, "per_bch", "bch_podf", base + 0x78, 12));
> +       clk_dm(IMX6UL_CLK_GPMI_BCH_APB,
> +              imx_clk_gate2(dev, "gpmi_bch_apb", "bch_podf", base + 0x78, 24));
> +       clk_dm(IMX6UL_CLK_GPMI_BCH,
> +              imx_clk_gate2(dev, "gpmi_bch", "gpmi_podf", base + 0x78, 26));
> +       clk_dm(IMX6UL_CLK_GPMI_IO,
> +              imx_clk_gate2(dev, "gpmi_io", "enfc_podf", base + 0x78, 28));
> +       clk_dm(IMX6UL_CLK_GPMI_APB,
> +              imx_clk_gate2(dev, "gpmi_apb", "bch_podf", base + 0x78, 30));
> +#endif
> +       clk_dm(IMX6UL_CLK_IPG,
> +              imx_clk_divider(dev, "ipg", "ahb", base + 0x14, 8, 2));

Sorry again, but the line here with IMX6UL_CLK_IPG is a duplicate of the one above.
It should be removed.

> +       clk_dm(IMX6UL_CLK_I2C1,
> +              imx_clk_gate2(dev, "i2c1", "perclk", base + 0x70, 6));
> +       clk_dm(IMX6UL_CLK_I2C2,
> +              imx_clk_gate2(dev, "i2c2", "perclk", base + 0x70, 8));
> +       clk_dm(IMX6UL_CLK_I2C3,
> +              imx_clk_gate2(dev, "i2c3", "perclk", base + 0x70, 10));
> +       clk_dm(IMX6UL_CLK_PWM1,
> +              imx_clk_gate2(dev, "pwm1", "perclk", base + 0x78, 16));
> +
> +       clk_dm(IMX6UL_CLK_ENET,
> +              imx_clk_gate2(dev, "enet", "ipg", base + 0x6c, 10));
> +       clk_dm(IMX6UL_CLK_ENET_REF,
> +              imx_clk_fixed_factor(dev, "enet_ref", "pll6_enet", 1, 1));
> +
> +       struct clk *clk, *clk1;
> +
> +       clk_get_by_id(IMX6UL_CLK_ENFC_SEL, &clk);
> +       clk_get_by_id(IMX6UL_CLK_PLL2_PFD2, &clk1);
> +
> +       clk_set_parent(clk, clk1);
> +
> +       return 0;
> +}
> +
> +static const struct udevice_id imx6ul_clk_ids[] = {
> +       {.compatible = "fsl,imx6ul-ccm" },
           ^
           |
If you want you could add a space here for consistency with the other drivers.

> +       { },
> +};
> +
> +U_BOOT_DRIVER(imx6ul_clk) = {
> +       .name = "clk_imx6ul",
> +       .id = UCLASS_CLK,
> +       .of_match = imx6ul_clk_ids,
> +       .ops = &imx6ul_clk_ops,
> +       .probe = imx6ul_clk_probe,
> +       .flags = DM_FLAG_PRE_RELOC,
> +};

I have only an imx6ull for testing. At the moment it looks good, although 
the Ethernet on my device is not yet working with this clock driver. I need
to find out why it's not working and will probably do a follow up patch. 

With that changes above
Reviewed-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>

Regards
Christoph