diff mbox series

[v8,4/4] clk: meson: add sub MMC clock controller driver

Message ID 1545063850-21504-5-git-send-email-jianxin.pan@amlogic.com (mailing list archive)
State New, archived
Headers show
Series clk: meson: add a sub EMMC clock controller support | expand

Commit Message

Jianxin Pan Dec. 17, 2018, 4:24 p.m. UTC 
From: Yixun Lan <yixun.lan@amlogic.com>

The patch will add a MMC clock controller driver which used by MMC or NAND,
It provide a mux and divider clock, and three phase clocks - core, tx, tx.

Two clocks are provided as the parent of MMC clock controller from
upper layer clock controller - eg "amlogic,axg-clkc" in AXG platform.

To specify which clock the MMC or NAND driver may consume,
the preprocessor macros in the dt-bindings/clock/amlogic,mmc-clkc.h header
can be used in the device tree sources.

Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Jianxin Pan <jianxin.pan@amlogic.com>
---
 drivers/clk/meson/Kconfig    |   9 ++
 drivers/clk/meson/Makefile   |   1 +
 drivers/clk/meson/mmc-clkc.c | 304 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 314 insertions(+)
 create mode 100644 drivers/clk/meson/mmc-clkc.c

Comments

kernel test robot Dec. 17, 2018, 8:33 p.m. UTC | #1 
Hi Yixun,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on clk/clk-next]
[also build test ERROR on next-20181217]
[cannot apply to v4.20-rc7]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Jianxin-Pan/clk-meson-add-one-based-divider-support-for-sclk-divider/20181218-021139
base:   https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git clk-next
config: sh-allmodconfig (attached as .config)
compiler: sh4-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.2.0 make.cross ARCH=sh 

All error/warnings (new ones prefixed by >>):

   In file included from include/linux/cache.h:5:0,
                    from include/linux/printk.h:9,
                    from include/linux/kernel.h:14,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk//meson/clk-phase-delay.c:13:
   drivers/clk//meson/clk-phase-delay.c: In function 'meson_clk_phase_delay_get_phase':
>> drivers/clk//meson/clk-phase-delay.c:33:40: warning: integer overflow in expression [-Woverflow]
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000,
                                           ^
   include/uapi/linux/kernel.h:13:40: note: in definition of macro '__KERNEL_DIV_ROUND_UP'
    #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
                                           ^
>> drivers/clk//meson/clk-phase-delay.c:33:14: note: in expansion of macro 'DIV_ROUND_UP'
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000,
                 ^~~~~~~~~~~~
   drivers/clk//meson/clk-phase-delay.c: In function 'meson_clk_phase_delay_set_phase':
   drivers/clk//meson/clk-phase-delay.c:50:40: warning: integer overflow in expression [-Woverflow]
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000, clk_hw_get_rate(hw));
                                           ^
   include/uapi/linux/kernel.h:13:40: note: in definition of macro '__KERNEL_DIV_ROUND_UP'
    #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
                                           ^
   drivers/clk//meson/clk-phase-delay.c:50:14: note: in expansion of macro 'DIV_ROUND_UP'
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000, clk_hw_get_rate(hw));
                 ^~~~~~~~~~~~
   In file included from ./arch/sh/include/generated/asm/div64.h:1:0,
                    from include/linux/kernel.h:207,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk//meson/clk-phase-delay.c:13:
   include/asm-generic/div64.h:222:28: warning: comparison of distinct pointer types lacks a cast
     (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
                               ^
>> drivers/clk//meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   In file included from include/linux/init.h:5:0,
                    from include/linux/io.h:22,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk//meson/clk-phase-delay.c:13:
   include/asm-generic/div64.h:235:25: warning: right shift count >= width of type [-Wshift-count-overflow]
     } else if (likely(((n) >> 32) == 0)) {  \
                            ^
   include/linux/compiler.h:76:40: note: in definition of macro 'likely'
    # define likely(x) __builtin_expect(!!(x), 1)
                                           ^
>> drivers/clk//meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   In file included from ./arch/sh/include/generated/asm/div64.h:1:0,
                    from include/linux/kernel.h:207,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk//meson/clk-phase-delay.c:13:
>> include/asm-generic/div64.h:239:22: error: passing argument 1 of '__div64_32' from incompatible pointer type [-Werror=incompatible-pointer-types]
      __rem = __div64_32(&(n), __base); \
                         ^
>> drivers/clk//meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   include/asm-generic/div64.h:213:17: note: expected 'uint64_t * {aka long long unsigned int *}' but argument is of type 'int *'
    extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
                    ^~~~~~~~~~
   cc1: some warnings being treated as errors
--
   In file included from include/linux/cache.h:5:0,
                    from include/linux/printk.h:9,
                    from include/linux/kernel.h:14,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk/meson/clk-phase-delay.c:13:
   drivers/clk/meson/clk-phase-delay.c: In function 'meson_clk_phase_delay_get_phase':
   drivers/clk/meson/clk-phase-delay.c:33:40: warning: integer overflow in expression [-Woverflow]
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000,
                                           ^
   include/uapi/linux/kernel.h:13:40: note: in definition of macro '__KERNEL_DIV_ROUND_UP'
    #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
                                           ^
   drivers/clk/meson/clk-phase-delay.c:33:14: note: in expansion of macro 'DIV_ROUND_UP'
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000,
                 ^~~~~~~~~~~~
   drivers/clk/meson/clk-phase-delay.c: In function 'meson_clk_phase_delay_set_phase':
   drivers/clk/meson/clk-phase-delay.c:50:40: warning: integer overflow in expression [-Woverflow]
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000, clk_hw_get_rate(hw));
                                           ^
   include/uapi/linux/kernel.h:13:40: note: in definition of macro '__KERNEL_DIV_ROUND_UP'
    #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
                                           ^
   drivers/clk/meson/clk-phase-delay.c:50:14: note: in expansion of macro 'DIV_ROUND_UP'
     period_ps = DIV_ROUND_UP(NSEC_PER_SEC * 1000, clk_hw_get_rate(hw));
                 ^~~~~~~~~~~~
   In file included from ./arch/sh/include/generated/asm/div64.h:1:0,
                    from include/linux/kernel.h:207,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk/meson/clk-phase-delay.c:13:
   include/asm-generic/div64.h:222:28: warning: comparison of distinct pointer types lacks a cast
     (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
                               ^
   drivers/clk/meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   In file included from include/linux/init.h:5:0,
                    from include/linux/io.h:22,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk/meson/clk-phase-delay.c:13:
   include/asm-generic/div64.h:235:25: warning: right shift count >= width of type [-Wshift-count-overflow]
     } else if (likely(((n) >> 32) == 0)) {  \
                            ^
   include/linux/compiler.h:76:40: note: in definition of macro 'likely'
    # define likely(x) __builtin_expect(!!(x), 1)
                                           ^
   drivers/clk/meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   In file included from ./arch/sh/include/generated/asm/div64.h:1:0,
                    from include/linux/kernel.h:207,
                    from include/asm-generic/bug.h:18,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/io.h:23,
                    from include/linux/clk-provider.h:9,
                    from drivers/clk/meson/clk-phase-delay.c:13:
>> include/asm-generic/div64.h:239:22: error: passing argument 1 of '__div64_32' from incompatible pointer type [-Werror=incompatible-pointer-types]
      __rem = __div64_32(&(n), __base); \
                         ^
   drivers/clk/meson/clk-phase-delay.c:56:6: note: in expansion of macro 'do_div'
     r = do_div(degrees, 360 / 1 << (ph->phase.width));
         ^~~~~~
   include/asm-generic/div64.h:213:17: note: expected 'uint64_t * {aka long long unsigned int *}' but argument is of type 'int *'
    extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
                    ^~~~~~~~~~
   cc1: some warnings being treated as errors

vim +/__div64_32 +239 include/asm-generic/div64.h

^1da177e Linus Torvalds 2005-04-16  215  
^1da177e Linus Torvalds 2005-04-16  216  /* The unnecessary pointer compare is there
^1da177e Linus Torvalds 2005-04-16  217   * to check for type safety (n must be 64bit)
^1da177e Linus Torvalds 2005-04-16  218   */
^1da177e Linus Torvalds 2005-04-16  219  # define do_div(n,base) ({				\
^1da177e Linus Torvalds 2005-04-16  220  	uint32_t __base = (base);			\
^1da177e Linus Torvalds 2005-04-16  221  	uint32_t __rem;					\
^1da177e Linus Torvalds 2005-04-16  222  	(void)(((typeof((n)) *)0) == ((uint64_t *)0));	\
911918aa Nicolas Pitre  2015-11-02  223  	if (__builtin_constant_p(__base) &&		\
911918aa Nicolas Pitre  2015-11-02  224  	    is_power_of_2(__base)) {			\
911918aa Nicolas Pitre  2015-11-02  225  		__rem = (n) & (__base - 1);		\
911918aa Nicolas Pitre  2015-11-02  226  		(n) >>= ilog2(__base);			\
461a5e51 Nicolas Pitre  2015-10-30  227  	} else if (__div64_const32_is_OK &&		\
461a5e51 Nicolas Pitre  2015-10-30  228  		   __builtin_constant_p(__base) &&	\
461a5e51 Nicolas Pitre  2015-10-30  229  		   __base != 0) {			\
461a5e51 Nicolas Pitre  2015-10-30  230  		uint32_t __res_lo, __n_lo = (n);	\
461a5e51 Nicolas Pitre  2015-10-30  231  		(n) = __div64_const32(n, __base);	\
461a5e51 Nicolas Pitre  2015-10-30  232  		/* the remainder can be computed with 32-bit regs */ \
461a5e51 Nicolas Pitre  2015-10-30  233  		__res_lo = (n);				\
461a5e51 Nicolas Pitre  2015-10-30  234  		__rem = __n_lo - __res_lo * __base;	\
911918aa Nicolas Pitre  2015-11-02  235  	} else if (likely(((n) >> 32) == 0)) {		\
^1da177e Linus Torvalds 2005-04-16  236  		__rem = (uint32_t)(n) % __base;		\
^1da177e Linus Torvalds 2005-04-16  237  		(n) = (uint32_t)(n) / __base;		\
^1da177e Linus Torvalds 2005-04-16  238  	} else 						\
^1da177e Linus Torvalds 2005-04-16 @239  		__rem = __div64_32(&(n), __base);	\
^1da177e Linus Torvalds 2005-04-16  240  	__rem;						\
^1da177e Linus Torvalds 2005-04-16  241   })
^1da177e Linus Torvalds 2005-04-16  242  

:::::: The code at line 239 was first introduced by commit
:::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2

:::::: TO: Linus Torvalds <torvalds@ppc970.osdl.org>
:::::: CC: Linus Torvalds <torvalds@ppc970.osdl.org>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Stephen Boyd Jan. 9, 2019, 8:48 p.m. UTC | #2 
Quoting Jianxin Pan (2018-12-17 08:24:10)
> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
> new file mode 100644
> index 0000000..2582a98
> --- /dev/null
> +++ b/drivers/clk/meson/mmc-clkc.c
> @@ -0,0 +1,304 @@
> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> +/*
> + * Amlogic Meson MMC Sub Clock Controller Driver
> + *
> + * Copyright (c) 2017 Baylibre SAS.
> + * Author: Jerome Brunet <jbrunet@baylibre.com>
> + *
> + * Copyright (c) 2018 Amlogic, inc.
> + * Author: Yixun Lan <yixun.lan@amlogic.com>
> + * Author: Jianxin Pan <jianxin.pan@amlogic.com>
> + */
> +
> +#include <linux/clk.h>

Do you need this include?

> +#include <linux/clk-provider.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/of_device.h>
> +#include <linux/mfd/syscon.h>

Is this used?

> +#include <linux/platform_device.h>
[...]
> +       init.num_parents = 1;
> +
> +       clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
> +       if (IS_ERR(clk))
> +               dev_err(dev, "%s clock registration failed\n", suffix);
> +
> +       return clk;
> +}
> +
> +static int mmc_clkc_probe(struct platform_device *pdev)
> +{
> +       struct clk_hw_onecell_data *onecell_data;
> +       struct device *dev = &pdev->dev;
> +       struct mmc_clkc_data *data;
> +       struct regmap *map;
> +       struct clk_regmap *clk, *core;
> +       struct meson_sclk_div_data *div_data;
> +
> +       /*cast to drop the const in match->data*/
> +       data = (struct mmc_clkc_data *)of_device_get_match_data(dev);

Is that necessary? Maybe the users of this should take a const argument
and copy things?

> +       if (!data)
> +               return -ENODEV;
> +
> +       map = syscon_node_to_regmap(dev->of_node);
> +       if (IS_ERR(map)) {
> +               dev_err(dev, "could not find mmc clock controller\n");
> +               return PTR_ERR(map);
> +       }
> +
> +       onecell_data = devm_kzalloc(dev, sizeof(*onecell_data) +
> +                                   sizeof(*onecell_data->hws) * MMC_MAX_CLKS,

struct_size()?
Jianxin Pan Jan. 15, 2019, 4:29 p.m. UTC | #3 
Hi Stephen,

Thank you for your time.
Please see my comments below.

On 2019/1/10 4:48, Stephen Boyd wrote:
> Quoting Jianxin Pan (2018-12-17 08:24:10)
>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
>> new file mode 100644
>> index 0000000..2582a98
>> --- /dev/null
>> +++ b/drivers/clk/meson/mmc-clkc.c
>> @@ -0,0 +1,304 @@
>> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
>> +/*
>> + * Amlogic Meson MMC Sub Clock Controller Driver
>> + *
>> + * Copyright (c) 2017 Baylibre SAS.
>> + * Author: Jerome Brunet <jbrunet@baylibre.com>
>> + *
>> + * Copyright (c) 2018 Amlogic, inc.
>> + * Author: Yixun Lan <yixun.lan@amlogic.com>
>> + * Author: Jianxin Pan <jianxin.pan@amlogic.com>
>> + */
>> +
>> +#include <linux/clk.h>
> 
> Do you need this include?
> 
Yes, It's also a clock-consumer. 
devm_clk_get() gets clock from dts as the parent of mux.
Thank you for your review.
>> +#include <linux/clk-provider.h>
>> +#include <linux/module.h>
>> +#include <linux/regmap.h>
>> +#include <linux/slab.h>
>> +#include <linux/of_device.h>
>> +#include <linux/mfd/syscon.h>
> 
> Is this used?
Yes, syscon_node_to_regmap() is used in mmc_clkc_probe().
> 
>> +#include <linux/platform_device.h>
> [...]
>> +       init.num_parents = 1;
>> +
>> +       clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
>> +       if (IS_ERR(clk))
>> +               dev_err(dev, "%s clock registration failed\n", suffix);
>> +
>> +       return clk;
>> +}
>> +
>> +static int mmc_clkc_probe(struct platform_device *pdev)
>> +{
>> +       struct clk_hw_onecell_data *onecell_data;
>> +       struct device *dev = &pdev->dev;
>> +       struct mmc_clkc_data *data;
>> +       struct regmap *map;
>> +       struct clk_regmap *clk, *core;
>> +       struct meson_sclk_div_data *div_data;
>> +
>> +       /*cast to drop the const in match->data*/
>> +       data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
> 
> Is that necessary? Maybe the users of this should take a const argument
> and copy things?
OK, I can alloc two extra memory for PHASE_RX and PHASE_TX data, and then copy from const data to them.
> 
>> +       if (!data)
>> +               return -ENODEV;
>> +
>> +       map = syscon_node_to_regmap(dev->of_node);
>> +       if (IS_ERR(map)) {
>> +               dev_err(dev, "could not find mmc clock controller\n");
>> +               return PTR_ERR(map);
>> +       }
>> +
>> +       onecell_data = devm_kzalloc(dev, sizeof(*onecell_data) +
>> +                                   sizeof(*onecell_data->hws) * MMC_MAX_CLKS,
> 
> struct_size()?
> 
OK, I will change it in the next version.
Thank you for your review.
> .
>
diff mbox series

Patch

diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
index efaa70f..c84b0f7 100644
--- a/drivers/clk/meson/Kconfig
+++ b/drivers/clk/meson/Kconfig
@@ -15,6 +15,15 @@  config COMMON_CLK_MESON_AO
 	select COMMON_CLK_REGMAP_MESON
 	select RESET_CONTROLLER
 
+config COMMON_CLK_MMC_MESON
+	tristate "Meson MMC Sub Clock Controller Driver"
+	select MFD_SYSCON
+	select COMMON_CLK_AMLOGIC
+	help
+	  Support for the MMC sub clock controller on Amlogic Meson Platform,
+	  which include S905 (GXBB, GXL), A113D/X (AXG) devices.
+	  Say Y if you want this clock enabled.
+
 config COMMON_CLK_REGMAP_MESON
 	bool
 	select REGMAP
diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index d59620d..54416a2 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -12,4 +12,5 @@  obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o
 obj-$(CONFIG_COMMON_CLK_GXBB)	 += gxbb.o gxbb-aoclk.o gxbb-aoclk-32k.o
 obj-$(CONFIG_COMMON_CLK_AXG)	 += axg.o axg-aoclk.o
 obj-$(CONFIG_COMMON_CLK_AXG_AUDIO)	+= axg-audio.o
+obj-$(CONFIG_COMMON_CLK_MMC_MESON) 	+= mmc-clkc.o
 obj-$(CONFIG_COMMON_CLK_REGMAP_MESON)	+= clk-regmap.o
diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
new file mode 100644
index 0000000..2582a98
--- /dev/null
+++ b/drivers/clk/meson/mmc-clkc.c
@@ -0,0 +1,304 @@ 
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Amlogic Meson MMC Sub Clock Controller Driver
+ *
+ * Copyright (c) 2017 Baylibre SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ *
+ * Copyright (c) 2018 Amlogic, inc.
+ * Author: Yixun Lan <yixun.lan@amlogic.com>
+ * Author: Jianxin Pan <jianxin.pan@amlogic.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/clock/amlogic,mmc-clkc.h>
+
+#include "clkc.h"
+
+/* clock ID used by internal driver */
+
+#define SD_EMMC_CLOCK		0
+#define CLK_DELAY_STEP_PS	200
+#define MUX_CLK_NUM_PARENTS	2
+#define MMC_MAX_CLKS		4
+
+struct mmc_clkc_data {
+	struct meson_clk_phase_delay_data tx;
+	struct meson_clk_phase_delay_data rx;
+};
+
+static struct clk_regmap_mux_data mmc_clkc_mux_data = {
+	.offset = SD_EMMC_CLOCK,
+	.mask   = 0x3,
+	.shift  = 6,
+};
+
+static const struct meson_sclk_div_data mmc_clkc_div_data = {
+	.div = {
+		.reg_off = SD_EMMC_CLOCK,
+		.width   = 6,
+	},
+	.flags = CLK_DIVIDER_ONE_BASED,
+};
+
+static struct meson_clk_phase_data mmc_clkc_core_phase = {
+	.ph = {
+		.reg_off = SD_EMMC_CLOCK,
+		.shift   = 8,
+		.width   = 2,
+	}
+};
+
+static const struct mmc_clkc_data mmc_clkc_gx_data = {
+	.tx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 10,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 16,
+			.width   = 4,
+		},
+		.delay_step_ps = CLK_DELAY_STEP_PS,
+	},
+	.rx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 12,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 20,
+			.width   = 4,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS,
+	},
+};
+
+static const struct mmc_clkc_data mmc_clkc_axg_data = {
+	.tx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 10,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 16,
+			.width   = 6,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS,
+	},
+	.rx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 12,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 22,
+			.width   = 6,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS,
+	},
+};
+
+static const struct of_device_id mmc_clkc_match_table[] = {
+	{
+		.compatible	= "amlogic,gx-mmc-clkc",
+		.data		= &mmc_clkc_gx_data
+	},
+	{
+		.compatible	= "amlogic,axg-mmc-clkc",
+		.data		= &mmc_clkc_axg_data
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, mmc_clkc_match_table);
+
+static struct clk_regmap *
+mmc_clkc_register_clk(struct device *dev, struct regmap *map,
+		      struct clk_init_data *init,
+		      const char *suffix, void *data)
+{
+	struct clk_regmap *clk;
+	char *name;
+	int ret;
+
+	clk = devm_kzalloc(dev, sizeof(*clk), GFP_KERNEL);
+	if (!clk)
+		return ERR_PTR(-ENOMEM);
+
+	name = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), suffix);
+	if (!name)
+		return ERR_PTR(-ENOMEM);
+
+	init->name = name;
+	clk->map = map;
+	clk->data = data;
+	clk->hw.init = init;
+	ret = devm_clk_hw_register(dev, &clk->hw);
+	if (ret)
+		clk = ERR_PTR(ret);
+
+	kfree(name);
+	return clk;
+}
+
+static struct clk_regmap *mmc_clkc_register_mux(struct device *dev,
+						struct regmap *map)
+{
+	const char *parent_names[MUX_CLK_NUM_PARENTS];
+	struct clk_init_data init;
+	struct clk_regmap *mux;
+	struct clk *clk;
+	int i;
+
+	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
+		char name[8];
+
+		snprintf(name, sizeof(name), "clkin%d", i);
+		clk = devm_clk_get(dev, name);
+		if (IS_ERR(clk)) {
+			if (clk != ERR_PTR(-EPROBE_DEFER))
+				dev_err(dev, "Missing clock %s\n", name);
+			return ERR_CAST(clk);
+		}
+
+		parent_names[i] = __clk_get_name(clk);
+	}
+
+	init.ops = &clk_regmap_mux_ops;
+	init.flags = CLK_SET_RATE_PARENT;
+	init.parent_names = parent_names;
+	init.num_parents = MUX_CLK_NUM_PARENTS;
+
+	mux = mmc_clkc_register_clk(dev, map, &init, "mux", &mmc_clkc_mux_data);
+	if (IS_ERR(mux))
+		dev_err(dev, "Mux clock registration failed\n");
+
+	return mux;
+}
+
+static struct clk_regmap *
+mmc_clkc_register_clk_with_parent(struct device *dev, struct regmap *map,
+				  char *suffix, const struct clk_hw *hw,
+				  unsigned long flags,
+				  const struct clk_ops *ops, void *data)
+{
+	struct clk_init_data init;
+	struct clk_regmap *clk;
+	const char *parent_name = clk_hw_get_name(hw);
+
+	init.ops = ops;
+	init.flags = flags;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
+	if (IS_ERR(clk))
+		dev_err(dev, "%s clock registration failed\n", suffix);
+
+	return clk;
+}
+
+static int mmc_clkc_probe(struct platform_device *pdev)
+{
+	struct clk_hw_onecell_data *onecell_data;
+	struct device *dev = &pdev->dev;
+	struct mmc_clkc_data *data;
+	struct regmap *map;
+	struct clk_regmap *clk, *core;
+	struct meson_sclk_div_data *div_data;
+
+	/*cast to drop the const in match->data*/
+	data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
+	if (!data)
+		return -ENODEV;
+
+	map = syscon_node_to_regmap(dev->of_node);
+	if (IS_ERR(map)) {
+		dev_err(dev, "could not find mmc clock controller\n");
+		return PTR_ERR(map);
+	}
+
+	onecell_data = devm_kzalloc(dev, sizeof(*onecell_data) +
+				    sizeof(*onecell_data->hws) * MMC_MAX_CLKS,
+				    GFP_KERNEL);
+	if (!onecell_data)
+		return -ENOMEM;
+
+	clk = mmc_clkc_register_mux(dev, map);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	div_data = devm_kzalloc(dev, sizeof(*div_data), GFP_KERNEL);
+	if (!div_data)
+		return -ENOMEM;
+
+	memcpy(div_data, &mmc_clkc_div_data, sizeof(*div_data));
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "div",
+						&clk->hw,
+						CLK_SET_RATE_PARENT,
+						&meson_sclk_div_ops,
+						div_data);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_DIV] = &clk->hw,
+
+	core = mmc_clkc_register_clk_with_parent(dev, map, "core",
+						 &clk->hw,
+						 CLK_SET_RATE_PARENT,
+						 &meson_clk_phase_ops,
+						 &mmc_clkc_core_phase);
+	if (IS_ERR(core))
+		return PTR_ERR(core);
+
+	onecell_data->hws[CLKID_MMC_PHASE_CORE] = &core->hw,
+
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "rx",
+						&core->hw,  0,
+						&meson_clk_phase_delay_ops,
+						&data->rx);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_PHASE_RX] = &clk->hw,
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "tx",
+						&core->hw,  0,
+						&meson_clk_phase_delay_ops,
+						&data->tx);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_PHASE_TX] = &clk->hw,
+	onecell_data->num = MMC_MAX_CLKS;
+	return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+					   onecell_data);
+}
+
+static struct platform_driver mmc_clkc_driver = {
+	.probe		= mmc_clkc_probe,
+	.driver		= {
+		.name	= "meson-mmc-clkc",
+		.of_match_table = of_match_ptr(mmc_clkc_match_table),
+	},
+};
+
+module_platform_driver(mmc_clkc_driver);
+
+MODULE_DESCRIPTION("Amlogic AXG MMC clock driver");
+MODULE_AUTHOR("Jianxin Pan <jianxin.pan@amlogic.com>");
+MODULE_LICENSE("GPL v2");