Re: [PATCH V2] clk: clk_versaclock: Add support for versaclock driver

Sean Anderson
2021-06-03T16:33:22Z

On 6/3/21 8:28 AM, Adam Ford wrote:
> The driver is based on the Versaclock driver from the Linux code, but
> due to the differences in the clock API between U-Boot and Linux, some
> pieces had to be changed.
>
> This driver creates a mux, pfd, pll, and a series of fod ouputs.
> Rate Usecnt Name
> ------------------------------------------
> 25000000 0 `-- x304-clock
> 25000000 0 `-- clock-controller@6a.mux
> 25000000 0 |-- clock-controller@6a.pfd
> 2800000000 0 | `-- clock-controller@6a.pll
> 33333333 0 | |-- clock-controller@6a.fod0
> 33333333 0 | | `-- clock-controller@6a.out1
> 33333333 0 | |-- clock-controller@6a.fod1
> 33333333 0 | | `-- clock-controller@6a.out2
> 50000000 0 | |-- clock-controller@6a.fod2
> 50000000 0 | | `-- clock-controller@6a.out3
> 125000000 0 | `-- clock-controller@6a.fod3
> 125000000 0 | `-- clock-controller@6a.out4
> 25000000 0 `-- clock-controller@6a.out0_sel_i2cb
>
> A translation function is added so the references to <&versaclock X> get routed
> to the corresponding clock-controller@6a.outX.
>
> Signed-off-by: Adam Ford <aford173@gmail.com>
>
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index 40a5a5dd88..2a7507ea18 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -197,4 +197,13 @@ config SANDBOX_CLK_CCF
> Enable this option if you want to test the Linux kernel's Common
> Clock Framework [CCF] code in U-Boot's Sandbox clock driver.
>
> +config CLK_VERSACLOCK
> + tristate "Enable VersaClock 5/6 devices"
> + depends on CLK
> + depends on CLK_CCF
> + depends on OF_CONTROL
> + help
> + This driver supports the IDT VersaClock 5 and VersaClock 6
> + programmable clock generators.
> +
> endmenu
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 645709b855..6f5ddafd64 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -51,3 +51,4 @@ obj-$(CONFIG_SANDBOX_CLK_CCF) += clk_sandbox_ccf.o
> obj-$(CONFIG_STM32H7) += clk_stm32h7.o
> obj-$(CONFIG_CLK_VERSAL) += clk_versal.o
> obj-$(CONFIG_CLK_CDCE9XX) += clk-cdce9xx.o
> +obj-$(CONFIG_CLK_VERSACLOCK) += clk_versaclock.o
> diff --git a/drivers/clk/clk_versaclock.c b/drivers/clk/clk_versaclock.c
> new file mode 100644
> index 0000000000..ee5562978a
> --- /dev/null
> +++ b/drivers/clk/clk_versaclock.c
> @@ -0,0 +1,979 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Driver for IDT Versaclock 5/6
> + *
> + * Derived from code Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
> + */
> +
> +#include <common.h>
> +#include <clk.h>
> +#include <clk-uclass.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <i2c.h>
> +#include <dm/device_compat.h>
> +#include <log.h>
> +#include <linux/clk-provider.h>
> +#include <linux/kernel.h>
> +#include <linux/math64.h>
> +
> +#include <dt-bindings/clk/versaclock.h>
> +
> +/* Configuration register block */
> +#define VC5_PRIM_SRC_SHDN 0x10
> +#define VC5_PRIM_SRC_SHDN_EN_XTAL BIT(7)
> +#define VC5_PRIM_SRC_SHDN_EN_CLKIN BIT(6)
> +#define VC5_XTAL_X1_LOAD_CAP 0x12
> +#define VC5_XTAL_X2_LOAD_CAP 0x13
> +#define VC5_REF_DIVIDER 0x15
> +#define VC5_REF_DIVIDER_SEL_PREDIV2 BIT(7)
> +#define VC5_REF_DIVIDER_REF_DIV(n) ((n) & 0x3f)
> +#define VC5_VCO_CTRL_AND_PREDIV 0x16
> +#define VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV BIT(7)
> +#define VC5_FEEDBACK_INT_DIV 0x17
> +
> +/* Output divider control for divider 1,2,3,4 */
> +#define VC5_OUT_DIV_CONTROL(idx) (0x21 + ((idx) * 0x10))
> +#define VC5_OUT_DIV_CONTROL_RESET BIT(7)
> +#define VC5_OUT_DIV_CONTROL_SELB_NORM BIT(3)
> +#define VC5_OUT_DIV_CONTROL_SEL_EXT BIT(2)
> +#define VC5_OUT_DIV_CONTROL_EN_FOD BIT(0)
> +#define VC5_OUT_DIV_FRAC(idx, n) (0x22 + ((idx) * 0x10) + (n))
> +#define VC5_OUT_DIV_INT(idx, n) (0x2d + ((idx) * 0x10) + (n))
> +
> +/* Clock control register for clock 1,2 */
> +#define VC5_CLK_OUTPUT_CFG(idx, n) (0x60 + ((idx) * 0x2) + (n))
> +#define VC5_CLK_OUTPUT_CFG0_CFG_SHIFT 5
> +#define VC5_CLK_OUTPUT_CFG0_CFG_MASK GENMASK(7, VC5_CLK_OUTPUT_CFG0_CFG_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_LVPECL (VC5_LVPECL)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_CMOS (VC5_CMOS)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_HCSL33 (VC5_HCSL33)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_LVDS (VC5_LVDS)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_CMOS2 (VC5_CMOS2)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_CMOSD (VC5_CMOSD)
> +#define VC5_CLK_OUTPUT_CFG0_CFG_HCSL25 (VC5_HCSL25)
> +#define VC5_CLK_OUTPUT_CFG0_PWR_SHIFT 3
> +#define VC5_CLK_OUTPUT_CFG0_PWR_MASK GENMASK(4, VC5_CLK_OUTPUT_CFG0_PWR_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_PWR_18 (0 << VC5_CLK_OUTPUT_CFG0_PWR_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_PWR_25 (2 << VC5_CLK_OUTPUT_CFG0_PWR_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_PWR_33 (3 << VC5_CLK_OUTPUT_CFG0_PWR_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT 0
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_MASK GENMASK(1, VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_80 (0 << VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_85 (1 << VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_90 (2 << VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG0_SLEW_100 (3 << VC5_CLK_OUTPUT_CFG0_SLEW_SHIFT)
> +#define VC5_CLK_OUTPUT_CFG1_EN_CLKBUF BIT(0)
> +
> +#define VC5_GLOBAL_REGISTER 0x76
> +#define VC5_GLOBAL_REGISTER_GLOBAL_RESET BIT(5)
> +
> +/* PLL/VCO runs between 2.5 GHz and 3.0 GHz */
> +#define VC5_PLL_VCO_MIN 2500000000UL
> +#define VC5_PLL_VCO_MAX 3000000000UL
> +
> +/* VC5 Input mux settings */
> +#define VC5_MUX_IN_XIN BIT(0)
> +#define VC5_MUX_IN_CLKIN BIT(1)
> +
> +/* Maximum number of clk_out supported by this driver */
> +#define VC5_MAX_CLK_OUT_NUM 5
> +
> +/* Maximum number of FODs supported by this driver */
> +#define VC5_MAX_FOD_NUM 4
> +
> +/* flags to describe chip features */
> +/* chip has built-in oscilator */
> +#define VC5_HAS_INTERNAL_XTAL BIT(0)
> +/* chip has PFD requency doubler */
> +#define VC5_HAS_PFD_FREQ_DBL BIT(1)
> +
> +/* Supported IDT VC5 models. */
> +enum vc5_model {
> + IDT_VC5_5P49V5923,
> + IDT_VC5_5P49V5925,
> + IDT_VC5_5P49V5933,
> + IDT_VC5_5P49V5935,
> + IDT_VC6_5P49V6901,
> + IDT_VC6_5P49V6965,
> +};
> +
> +/* Structure to describe features of a particular VC5 model */
> +struct vc5_chip_info {
> + const enum vc5_model model;
> + const unsigned int clk_fod_cnt;
> + const unsigned int clk_out_cnt;
> + const u32 flags;
> +};
> +
> +struct vc5_driver_data;
> +
> +struct vc5_hw_data {
> + struct clk hw;
> + struct vc5_driver_data *vc5;
> + u32 div_int;
> + u32 div_frc;
> + unsigned int num;
> +};
> +
> +struct vc5_out_data {
> + struct clk hw;
> + struct vc5_driver_data *vc5;
> + unsigned int num;
> + unsigned int clk_output_cfg0;
> + unsigned int clk_output_cfg0_mask;
> +};
> +
> +struct vc5_driver_data {
> + struct udevice *i2c;
> + const struct vc5_chip_info *chip_info;
> +
> + struct clk *pin_xin;
> + struct clk *pin_clkin;
> + unsigned char clk_mux_ins;
> + struct clk clk_mux;
> + struct clk clk_mul;
> + struct clk clk_pfd;
> + struct vc5_hw_data clk_pll;
> + struct vc5_hw_data clk_fod[VC5_MAX_FOD_NUM];
> + struct vc5_out_data clk_out[VC5_MAX_CLK_OUT_NUM];
> +};
> +
> +static const struct vc5_chip_info idt_5p49v5923_info = {
> + .model = IDT_VC5_5P49V5923,
> + .clk_fod_cnt = 2,
> + .clk_out_cnt = 3,
> + .flags = 0,
> +};
> +
> +static const struct vc5_chip_info idt_5p49v5925_info = {
> + .model = IDT_VC5_5P49V5925,
> + .clk_fod_cnt = 4,
> + .clk_out_cnt = 5,
> + .flags = 0,
> +};
> +
> +static const struct vc5_chip_info idt_5p49v5933_info = {
> + .model = IDT_VC5_5P49V5933,
> + .clk_fod_cnt = 2,
> + .clk_out_cnt = 3,
> + .flags = VC5_HAS_INTERNAL_XTAL,
> +};
> +
> +static const struct vc5_chip_info idt_5p49v5935_info = {
> + .model = IDT_VC5_5P49V5935,
> + .clk_fod_cnt = 4,
> + .clk_out_cnt = 5,
> + .flags = VC5_HAS_INTERNAL_XTAL,
> +};
> +
> +static const struct vc5_chip_info idt_5p49v6901_info = {
> + .model = IDT_VC6_5P49V6901,
> + .clk_fod_cnt = 4,
> + .clk_out_cnt = 5,
> + .flags = VC5_HAS_PFD_FREQ_DBL,
> +};
> +
> +static const struct vc5_chip_info idt_5p49v6965_info = {
> + .model = IDT_VC6_5P49V6965,
> + .clk_fod_cnt = 4,
> + .clk_out_cnt = 5,
> + .flags = 0,
> +};
> +
> +static int vc5_update_bits(struct udevice *dev, unsigned int reg, unsigned int mask,
> + unsigned int src)
> +{
> + int ret;
> + unsigned char cache;
> +
> + ret = dm_i2c_read(dev, reg, &cache, 1);
> + if (ret < 0)
> + return ret;
> +
> + cache &= ~mask;
> + cache |= mask & src;
> + ret = dm_i2c_write(dev, reg, (uchar *)&cache, 1);
> +
> + return ret;
> +}
> +
> +static unsigned long vc5_mux_get_rate(struct clk *hw)
> +{
> + return clk_get_rate(clk_get_parent(hw));
> +}
> +
> +static int vc5_mux_set_parent(struct clk *hw, unsigned char index)
> +{
> + struct vc5_driver_data *vc5 = container_of(hw, struct vc5_driver_data, clk_mux);
> + const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
> + u8 src;
> +
> + if (index > 1 || !vc5->clk_mux_ins)
> + return -EINVAL;
> +
> + if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
> + if (index == 0)
> + src = VC5_PRIM_SRC_SHDN_EN_XTAL;
> + if (index == 1)
> + src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
> + } else {
> + if (index != 0)
> + return -EINVAL;
> +
> + if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
> + src = VC5_PRIM_SRC_SHDN_EN_XTAL;
> + else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
> + src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
> + else /* Invalid; should have been caught by vc5_probe() */
> + return -EINVAL;
> + }
> +
> + return vc5_update_bits(vc5->i2c, VC5_PRIM_SRC_SHDN, mask, src);
> +}
> +
> +static const struct clk_ops vc5_mux_ops = {
> + .get_rate = vc5_mux_get_rate,
> +};
> +
> +static unsigned long vc5_pfd_round_rate(struct clk *hw, unsigned long rate)
> +{
> + struct clk *clk_parent = clk_get_parent(hw);
> + unsigned long parent_rate = clk_get_rate(clk_parent);
> + unsigned long idiv;
> +
> + /* PLL cannot operate with input clock above 50 MHz. */
> + if (rate > 50000000)
> + return -EINVAL;
> +
> + /* CLKIN within range of PLL input, feed directly to PLL. */
> + if (parent_rate <= 50000000)
> + return parent_rate;
> +
> + idiv = DIV_ROUND_UP(parent_rate, rate);
> + if (idiv > 127)
> + return -EINVAL;
> +
> + return parent_rate / idiv;
> +}
> +
> +static unsigned long vc5_pfd_recalc_rate(struct clk *hw)
> +{
> + struct vc5_driver_data *vc5 =
> + container_of(hw, struct vc5_driver_data, clk_pfd);
> + unsigned int prediv, div;
> + struct clk *clk_parent = clk_get_parent(hw);
> + unsigned long parent_rate = clk_get_rate(clk_parent);
> +
> + dm_i2c_read(vc5->i2c, VC5_VCO_CTRL_AND_PREDIV, (uchar *)&prediv, 1);
> +
> + /* The bypass_prediv is set, PLL fed from Ref_in directly. */
> + if (prediv & VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV)
> + return parent_rate;
> +
> + dm_i2c_read(vc5->i2c, VC5_REF_DIVIDER, (uchar *)&div, 1);
> +
> + /* The Sel_prediv2 is set, PLL fed from prediv2 (Ref_in / 2) */
> + if (div & VC5_REF_DIVIDER_SEL_PREDIV2)
> + return parent_rate / 2;
> + else
> + return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
> +}
> +
> +static unsigned long vc5_pfd_set_rate(struct clk *hw, unsigned long rate)
> +{
> + struct vc5_driver_data *vc5 =
> + container_of(hw, struct vc5_driver_data, clk_pfd);
> + unsigned long idiv;
> + u8 div;
> + struct clk *clk_parent = clk_get_parent(hw);
> + unsigned long parent_rate = clk_get_rate(clk_parent);
> +
> + /* CLKIN within range of PLL input, feed directly to PLL. */
> + if (parent_rate <= 50000000) {
> + vc5_update_bits(vc5->i2c, VC5_VCO_CTRL_AND_PREDIV,
> + VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV,
> + VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV);
> + vc5_update_bits(vc5->i2c, VC5_REF_DIVIDER, 0xff, 0x00);
> + return 0;
> + }
> +
> + idiv = DIV_ROUND_UP(parent_rate, rate);
> +
> + /* We have dedicated div-2 predivider. */
> + if (idiv == 2)
> + div = VC5_REF_DIVIDER_SEL_PREDIV2;
> + else
> + div = VC5_REF_DIVIDER_REF_DIV(idiv);
> +
> + vc5_update_bits(vc5->i2c, VC5_REF_DIVIDER, 0xff, div);
> + vc5_update_bits(vc5->i2c, VC5_VCO_CTRL_AND_PREDIV,
> + VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV, 0);
> +
> + return 0;
> +}
> +
> +static const struct clk_ops vc5_pfd_ops = {
> + .round_rate = vc5_pfd_round_rate,
> + .get_rate = vc5_pfd_recalc_rate,
> + .set_rate = vc5_pfd_set_rate,
> +};
> +
> +/*
> + * VersaClock5 PLL/VCO
> + */
> +static unsigned long vc5_pll_recalc_rate(struct clk *hw)
> +{
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + struct vc5_driver_data *vc = hwdata->vc5;
> + struct clk *clk_parent = clk_get_parent(hw);
> + unsigned long parent_rate = clk_get_rate(clk_parent);
> + u32 div_int, div_frc;
> + u8 fb[5];
> +
> + dm_i2c_read(vc->i2c, VC5_FEEDBACK_INT_DIV, fb, 5);
> +
> + div_int = (fb[0] << 4) | (fb[1] >> 4);
> + div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
> +
> + /* The PLL divider has 12 integer bits and 24 fractional bits */
> + return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
> +}
> +
> +static unsigned long vc5_pll_round_rate(struct clk *hw, unsigned long rate)
> +{
> + struct clk *clk_parent = clk_get_parent(hw);
> + unsigned long parent_rate = clk_get_rate(clk_parent);
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + u32 div_int;
> + u64 div_frc;
> +
> + if (rate < VC5_PLL_VCO_MIN)
> + rate = VC5_PLL_VCO_MIN;
> + if (rate > VC5_PLL_VCO_MAX)
> + rate = VC5_PLL_VCO_MAX;
> +
> + /* Determine integer part, which is 12 bit wide */
> + div_int = rate / parent_rate;
> + if (div_int > 0xfff)
> + rate = parent_rate * 0xfff;
> +
> + /* Determine best fractional part, which is 24 bit wide */
> + div_frc = rate % parent_rate;
> + div_frc *= BIT(24) - 1;
> + do_div(div_frc, parent_rate);
> +
> + hwdata->div_int = div_int;
> + hwdata->div_frc = (u32)div_frc;
> +
> + return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
> +}
> +
> +static unsigned long vc5_pll_set_rate(struct clk *hw, unsigned long rate)
> +{
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + struct vc5_driver_data *vc5 = hwdata->vc5;
> + u8 fb[5];
> +
> + fb[0] = hwdata->div_int >> 4;
> + fb[1] = hwdata->div_int << 4;
> + fb[2] = hwdata->div_frc >> 16;
> + fb[3] = hwdata->div_frc >> 8;
> + fb[4] = hwdata->div_frc;
> +
> + return dm_i2c_write(vc5->i2c, VC5_FEEDBACK_INT_DIV, fb, 5);
> +}
> +
> +static const struct clk_ops vc5_pll_ops = {
> + .round_rate = vc5_pll_round_rate,
> + .get_rate = vc5_pll_recalc_rate,
> + .set_rate = vc5_pll_set_rate,
> +};
> +
> +static unsigned long vc5_fod_recalc_rate(struct clk *hw)
> +{
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + struct vc5_driver_data *vc = hwdata->vc5;
> + struct clk *parent = &vc->clk_pll.hw;
> + unsigned long parent_rate = vc5_pll_recalc_rate(parent);
> +
> + /* VCO frequency is divided by two before entering FOD */
> + u32 f_in = parent_rate / 2;
> + u32 div_int, div_frc;
> + u8 od_int[2];
> + u8 od_frc[4];
> +
> + dm_i2c_read(vc->i2c, VC5_OUT_DIV_INT(hwdata->num, 0), od_int, 2);
> + dm_i2c_read(vc->i2c, VC5_OUT_DIV_FRAC(hwdata->num, 0), od_frc, 4);
> +
> + div_int = (od_int[0] << 4) | (od_int[1] >> 4);
> + div_frc = (od_frc[0] << 22) | (od_frc[1] << 14) |
> + (od_frc[2] << 6) | (od_frc[3] >> 2);
> +
> + /* Avoid division by zero if the output is not configured. */
> + if (div_int == 0 && div_frc == 0)
> + return 0;
> +
> + /* The PLL divider has 12 integer bits and 30 fractional bits */
> + return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
> +}
> +
> +static unsigned long vc5_fod_round_rate(struct clk *hw, unsigned long rate)
> +{
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + struct vc5_driver_data *vc = hwdata->vc5;
> + struct clk *parent = &vc->clk_pll.hw;
> + unsigned long parent_rate = vc5_pll_recalc_rate(parent);
> +
> + /* VCO frequency is divided by two before entering FOD */
> + u32 f_in = parent_rate / 2;
> + u32 div_int;
> + u64 div_frc;
> +
> + /* Determine integer part, which is 12 bit wide */
> + div_int = f_in / rate;
> +
> + /*
> + * WARNING: The clock chip does not output signal if the integer part
> + * of the divider is 0xfff and fractional part is non-zero.
> + * Clamp the divider at 0xffe to keep the code simple.
> + */
> + if (div_int > 0xffe) {
> + div_int = 0xffe;
> + rate = f_in / div_int;
> + }
> +
> + /* Determine best fractional part, which is 30 bit wide */
> + div_frc = f_in % rate;
> + div_frc <<= 24;
> + do_div(div_frc, rate);
> +
> + hwdata->div_int = div_int;
> + hwdata->div_frc = (u32)div_frc;
> +
> + return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
> +}
> +
> +static unsigned long vc5_fod_set_rate(struct clk *hw, unsigned long rate)
> +{
> + struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
> + struct vc5_driver_data *vc5 = hwdata->vc5;
> +
> + u8 data[14] = {
> + hwdata->div_frc >> 22, hwdata->div_frc >> 14,
> + hwdata->div_frc >> 6, hwdata->div_frc << 2,
> + 0, 0, 0, 0, 0,
> + 0, 0,
> + hwdata->div_int >> 4, hwdata->div_int << 4,
> + 0
> + };
> +
> + dm_i2c_write(vc5->i2c, VC5_OUT_DIV_FRAC(hwdata->num, 0), data, 14);
> +
> + /*
> + * Toggle magic bit in undocumented register for unknown reason.
> + * This is what the IDT timing commander tool does and the chip
> + * datasheet somewhat implies this is needed, but the register
> + * and the bit is not documented.
> + */
> + vc5_update_bits(vc5->i2c, VC5_GLOBAL_REGISTER,
> + VC5_GLOBAL_REGISTER_GLOBAL_RESET, 0);
> + vc5_update_bits(vc5->i2c, VC5_GLOBAL_REGISTER,
> + VC5_GLOBAL_REGISTER_GLOBAL_RESET,
> + VC5_GLOBAL_REGISTER_GLOBAL_RESET);
> +
> + return 0;
> +}
> +
> +static const struct clk_ops vc5_fod_ops = {
> + .round_rate = vc5_fod_round_rate,
> + .get_rate = vc5_fod_recalc_rate,
> + .set_rate = vc5_fod_set_rate,
> +};
> +
> +static int vc5_clk_out_prepare(struct clk *hw)
> +{
> + struct udevice *dev;
> + struct vc5_driver_data *vc5;
> + struct vc5_out_data *hwdata;
> +
> + const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
> + VC5_OUT_DIV_CONTROL_SEL_EXT |
> + VC5_OUT_DIV_CONTROL_EN_FOD;
> + unsigned int src;
> + int ret;
> +
> + uclass_get_device_by_name(UCLASS_CLK, clk_hw_get_name(hw), &dev);
> + vc5 = dev_get_priv(dev);
> + hwdata = &vc5->clk_out[hw->id];
> +
> + /*
> + * If the input mux is disabled, enable it first and
> + * select source from matching FOD.
> + */
> +
> + dm_i2c_read(vc5->i2c, VC5_OUT_DIV_CONTROL(hwdata->num), (uchar *)&src, 1);
> +
> + if ((src & mask) == 0) {
> + src = VC5_OUT_DIV_CONTROL_RESET | VC5_OUT_DIV_CONTROL_EN_FOD;
> + ret = vc5_update_bits(vc5->i2c,
> + VC5_OUT_DIV_CONTROL(hwdata->num),
> + mask | VC5_OUT_DIV_CONTROL_RESET, src);
> + if (ret)
> + return ret;
> + }
> +
> + /* Enable the clock buffer */
> + vc5_update_bits(vc5->i2c, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
> + VC5_CLK_OUTPUT_CFG1_EN_CLKBUF,
> + VC5_CLK_OUTPUT_CFG1_EN_CLKBUF);
> + if (hwdata->clk_output_cfg0_mask) {
> + vc5_update_bits(vc5->i2c, VC5_CLK_OUTPUT_CFG(hwdata->num, 0),
> + hwdata->clk_output_cfg0_mask,
> + hwdata->clk_output_cfg0);
> + }
> +
> + return 0;
> +}
> +
> +static int vc5_clk_out_unprepare(struct clk *hw)
> +{
> + struct udevice *dev;
> + struct vc5_driver_data *vc5;
> + struct vc5_out_data *hwdata;
> + int ret;
> +
> + uclass_get_device_by_name(UCLASS_CLK, clk_hw_get_name(hw), &dev);
> + vc5 = dev_get_priv(dev);
> + hwdata = &vc5->clk_out[hw->id];
> +
> + /* Disable the clock buffer */
> + ret = vc5_update_bits(vc5->i2c, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
> + VC5_CLK_OUTPUT_CFG1_EN_CLKBUF, 0);
> +
> + return ret;
> +}
> +
> +static int vc5_clk_out_set_parent(struct vc5_driver_data *vc, u8 num, u8 index)
> +{
> + const u8 mask = VC5_OUT_DIV_CONTROL_RESET |
> + VC5_OUT_DIV_CONTROL_SELB_NORM |
> + VC5_OUT_DIV_CONTROL_SEL_EXT |
> + VC5_OUT_DIV_CONTROL_EN_FOD;
> + const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
> + VC5_OUT_DIV_CONTROL_SEL_EXT;
> + u8 src = VC5_OUT_DIV_CONTROL_RESET;
> +
> + if (index == 0)
> + src |= VC5_OUT_DIV_CONTROL_EN_FOD;
> + else
> + src |= extclk;
> +
> + return vc5_update_bits(vc->i2c, VC5_OUT_DIV_CONTROL(num), mask, src);
> +}
> +
> +/*
> + * The device references to the Versaclock point to the head, so xlate needs to
> + * redirect it to clk_out[idx]
> + */
> +static int vc5_clk_out_xlate(struct clk *hw, struct ofnode_phandle_args *args)
> +{
> + unsigned int idx = args->args[0];
> +
> + if (args->args_count != 1) {
> + debug("Invaild args_count: %d\n", args->args_count);
> + return -EINVAL;
> + }
> +
> + hw->id = idx;
> +
> + return 0;
> +}
> +
> +static unsigned long vc5_clk_out_set_rate(struct clk *hw, unsigned long rate)
> +{
> + struct udevice *dev;
> + struct vc5_driver_data *vc;
> + struct clk *parent;
> +
> + uclass_get_device_by_name(UCLASS_CLK, clk_hw_get_name(hw), &dev);
> + vc = dev_get_priv(dev);
> + parent = clk_get_parent(&vc->clk_out[hw->id].hw);
> +
> + /* setting the output rate really means setting the parent FOD rate */
> + return clk_set_rate(parent, clk_round_rate(parent, rate));
> +}
> +
> +static unsigned long vc5_clk_out_get_rate(struct clk *hw)
> +{
> + return clk_get_parent_rate(hw);
> +}
> +
> +static const struct clk_ops vc5_clk_out_ops = {
> + .enable = vc5_clk_out_prepare,
> + .disable = vc5_clk_out_unprepare,
> + .set_rate = vc5_clk_out_set_rate,
> + .get_rate = vc5_clk_out_get_rate,
> +};
> +
> +static const struct clk_ops vc5_clk_out_sel_ops = {
> + .enable = vc5_clk_out_prepare,
> + .disable = vc5_clk_out_unprepare,
> + .get_rate = vc5_clk_out_get_rate,
> +};
> +
> +static const struct clk_ops vc5_clk_ops = {
> + .enable = vc5_clk_out_prepare,
> + .disable = vc5_clk_out_unprepare,
> + .of_xlate = vc5_clk_out_xlate,
> + .set_rate = vc5_clk_out_set_rate,
> + .get_rate = vc5_clk_out_get_rate,
> +};
> +
> +static int vc5_map_index_to_output(const enum vc5_model model,
> + const unsigned int n)
> +{
> + switch (model) {
> + case IDT_VC5_5P49V5933:
> + return (n == 0) ? 0 : 3;
> + case IDT_VC5_5P49V5923:
> + case IDT_VC5_5P49V5925:
> + case IDT_VC5_5P49V5935:
> + case IDT_VC6_5P49V6901:
> + case IDT_VC6_5P49V6965:
> + default:
> + return n;
> + }
> +}
> +
> +static int vc5_update_mode(ofnode np_output,
> + struct vc5_out_data *clk_out)
> +{
> + u32 value;
> +
> + if (!ofnode_read_u32(np_output, "idt,mode", &value)) {
> + clk_out->clk_output_cfg0_mask |= VC5_CLK_OUTPUT_CFG0_CFG_MASK;
> + switch (value) {
> + case VC5_CLK_OUTPUT_CFG0_CFG_LVPECL:
> + case VC5_CLK_OUTPUT_CFG0_CFG_CMOS:
> + case VC5_CLK_OUTPUT_CFG0_CFG_HCSL33:
> + case VC5_CLK_OUTPUT_CFG0_CFG_LVDS:
> + case VC5_CLK_OUTPUT_CFG0_CFG_CMOS2:
> + case VC5_CLK_OUTPUT_CFG0_CFG_CMOSD:
> + case VC5_CLK_OUTPUT_CFG0_CFG_HCSL25:
> + clk_out->clk_output_cfg0 |=
> + value << VC5_CLK_OUTPUT_CFG0_CFG_SHIFT;
> + break;
> + default:
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int vc5_update_power(ofnode np_output, struct vc5_out_data *clk_out)
> +{
> + u32 value;
> +
> + if (!ofnode_read_u32(np_output, "idt,voltage-microvolt", &value)) {
> + clk_out->clk_output_cfg0_mask |= VC5_CLK_OUTPUT_CFG0_PWR_MASK;
> + switch (value) {
> + case 1800000:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_PWR_18;
> + break;
> + case 2500000:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_PWR_25;
> + break;
> + case 3300000:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_PWR_33;
> + break;
> + default:
> + return -EINVAL;
> + }
> + }
> + return 0;
> +}
> +
> +static int vc5_map_cap_value(u32 femtofarads)
> +{
> + int mapped_value;
> +
> + /*
> + * The datasheet explicitly states 9000 - 25000 with 0.5pF
> + * steps, but the Programmer's guide shows the steps are 0.430pF.
> + * After getting feedback from Renesas, the .5pF steps were the
> + * goal, but 430nF was the actual values.
> + * Because of this, the actual range goes to 22760 instead of 25000
> + */
> + if (femtofarads < 9000 || femtofarads > 22760)
> + return -EINVAL;
> +
> + /*
> + * The Programmer's guide shows XTAL[5:0] but in reality,
> + * XTAL[0] and XTAL[1] are both LSB which makes the math
> + * strange. With clarfication from Renesas, setting the
> + * values should be simpler by ignoring XTAL[0]
> + */
> + mapped_value = DIV_ROUND_CLOSEST(femtofarads - 9000, 430);
> +
> + /*
> + * Since the calculation ignores XTAL[0], there is one
> + * special case where mapped_value = 32. In reality, this means
> + * the real mapped value should be 111111b. In other cases,
> + * the mapped_value needs to be shifted 1 to the left.
> + */
> + if (mapped_value > 31)
> + mapped_value = 0x3f;
> + else
> + mapped_value <<= 1;
> +
> + return mapped_value;
> +}
> +
> +static int vc5_update_cap_load(ofnode node, struct vc5_driver_data *vc5)
> +{
> + u32 value;
> + int mapped_value;
> +
> + if (!ofnode_read_u32(node, "idt,xtal-load-femtofarads", &value)) {
> + mapped_value = vc5_map_cap_value(value);
> +
> + if (mapped_value < 0)
> + return mapped_value;
> +
> + /*
> + * The mapped_value is really the high 6 bits of
> + * VC5_XTAL_X1_LOAD_CAP and VC5_XTAL_X2_LOAD_CAP, so
> + * shift the value 2 places.
> + */
> + vc5_update_bits(vc5->i2c, VC5_XTAL_X1_LOAD_CAP, ~0x03, mapped_value << 2);
> + vc5_update_bits(vc5->i2c, VC5_XTAL_X2_LOAD_CAP, ~0x03, mapped_value << 2);
> + }
> +
> + return 0;
> +}
> +
> +static int vc5_update_slew(ofnode np_output, struct vc5_out_data *clk_out)
> +{
> + u32 value;
> +
> + if (!ofnode_read_u32(np_output, "idt,slew-percent", &value)) {
> + clk_out->clk_output_cfg0_mask |= VC5_CLK_OUTPUT_CFG0_SLEW_MASK;
> +
> + switch (value) {
> + case 80:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_SLEW_80;
> + break;
> + case 85:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_SLEW_85;
> + break;
> + case 90:
> + clk_out->clk_output_cfg0 |= VC5_CLK_OUTPUT_CFG0_SLEW_90;
> + break;
> + case 100:
> + clk_out->clk_output_cfg0 |=
> + VC5_CLK_OUTPUT_CFG0_SLEW_100;
> + break;
> + default:
> + return -EINVAL;
> + }
> + }
> + return 0;
> +}
> +
> +static int vc5_get_output_config(struct udevice *dev,
> + struct vc5_out_data *clk_out)
> +{
> + ofnode np_output;
> + char child_name[5];
> + int ret = 0;
> +
> + sprintf(child_name, "OUT%d", clk_out->num + 1);
> +
> + np_output = ofnode_find_subnode(dev_ofnode(dev), child_name);

No need to get the ofnode here. Just use dev_read_*

> +
> + if (!ofnode_valid(np_output)) {
> + printf("!ofnode_valid(np_output)\n");

Please use dev_dbg or similar (see below)

> + return 0;
> + }
> +
> + ret = vc5_update_mode(np_output, clk_out);
> + if (ret)
> + goto output_error;
> +
> + ret = vc5_update_power(np_output, clk_out);
> + if (ret)
> + goto output_error;
> +
> + ret = vc5_update_slew(np_output, clk_out);
> +
> +output_error:
> + if (ret)
> + pr_err("Invalid clock output configuration OUT%d\n", clk_out->num + 1);

ditto

> +
> + return ret;
> +}
> +
> +int versaclock_probe(struct udevice *dev)
> +{
> + struct vc5_driver_data *vc5 = dev_get_priv(dev);
> + struct vc5_chip_info *chip = (void *)dev_get_driver_data(dev);
> + unsigned int n, idx = 0;
> + char *mux_name, *pfd_name, *pll_name, *outsel_name;
> + char *out_name[VC5_MAX_CLK_OUT_NUM];
> + char *fod_name[VC5_MAX_FOD_NUM];
> + int ret;
> + u64 val;
> +
> + val = (u64)dev_read_addr_ptr(dev);
> + ret = i2c_get_chip(dev->parent, val, 1, &vc5->i2c);
> +
> + if (ret) {
> + dev_err(dev, "I2C probe failed.\n");

Errors during probe should use dev_dbg or log_msg_ret (c.f. the
commentary at the end of [1]). If you use log_*, remember to define
LOG_CATEGORY to DM_CLK (this is done automatically for dev_*).

[1] https://u-boot.readthedocs.io/en/latest/develop/driver-model/design.html?highlight=EINVAL#error-codes

> + return ret;
> + }
> +
> + vc5->chip_info = chip;
> + vc5->pin_xin = devm_clk_get(dev, "xin");
> +
> + if (IS_ERR(vc5->pin_xin))
> + dev_err(dev, "failed to get xin clock\n");
> +
> + ret = clk_enable(vc5->pin_xin);
> + if (ret)
> + dev_err(dev, "failed to enable XIN clock\n");
> +
> + vc5->pin_clkin = devm_clk_get(dev, "clkin");
> +
> + /* Register clock input mux */
> + if (!IS_ERR(vc5->pin_xin)) {
> + vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
> + } else if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL) {
> + if (IS_ERR(vc5->pin_xin))
> + return PTR_ERR(vc5->pin_xin);
> + vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
> + }
> +
> + mux_name = malloc(strlen(dev->name) + 4);

Don't we need + 5 for nul-terminator?

In general, I would recommend a pattern like

n = snprintf(NULL, 0, fmt, ...) + 1;
buf = malloc(n);
if (!buf) /* ... */ ;
snprintf(buf, n, fmt, ...);

so you don't have to worry about things like this.

> + sprintf(mux_name, "%s.mux", dev->name);
> + clk_register(&vc5->clk_mux, "versaclock-mux", mux_name, vc5->pin_xin->dev->name);
> +
> + if (!IS_ERR(vc5->pin_xin))
> + vc5_mux_set_parent(&vc5->clk_mux, 1);
> + else
> + vc5_mux_set_parent(&vc5->clk_mux, 0);
> +
> + /* Configure Optional Loading Capacitance for external XTAL */
> + if (!(vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL)) {
> + ret = vc5_update_cap_load(dev_ofnode(dev), vc5);
> + if (ret)
> + dev_err(dev, "failed to vc5_update_cap_load\n");
> + }
> +
> + /* Register PFD */
> + pfd_name = malloc(strlen(dev->name) + 5);
> + sprintf(pfd_name, "%s.pfd", dev->name);
> + clk_register(&vc5->clk_pfd, "versaclock-pfd", pfd_name, vc5->clk_mux.dev->name);
> +
> + /* Register PLL */
> + vc5->clk_pll.num = 0;
> + vc5->clk_pll.vc5 = vc5;
> + pll_name = malloc(strlen(dev->name) + 4);

ditto

> + sprintf(pll_name, "%s.pll", dev->name);
> + clk_register(&vc5->clk_pll.hw, "versaclock-pll", pll_name, vc5->clk_pfd.dev->name);
> +
> + /* Register FODs */
> + for (n = 0; n < vc5->chip_info->clk_fod_cnt; n++) {
> + fod_name[n] = malloc(strlen(dev->name) + 5);
> + sprintf(fod_name[n], "%s.fod%d", dev->name, n);

ditto

> + idx = vc5_map_index_to_output(vc5->chip_info->model, n);
> + vc5->clk_fod[n].num = idx;
> + vc5->clk_fod[n].vc5 = vc5;
> + ret = clk_register(&vc5->clk_fod[n].hw, "versaclock-fod", fod_name[n],
> + vc5->clk_pll.hw.dev->name);
> + }
> +
> + /* Register MUX-connected OUT0_I2C_SELB output */
> + vc5->clk_out[0].num = idx;
> + vc5->clk_out[0].vc5 = vc5;
> + outsel_name = malloc(strlen(dev->name) + 14); /* .out0_sel_i2cb */

ditto

> + sprintf(outsel_name, "%s.out0_sel_i2cb", dev->name);
> + ret = clk_register(&vc5->clk_out[0].hw, "versaclock-outsel", outsel_name,
> + vc5->clk_mux.dev->name);
> +
> + /* Register FOD-connected OUTx outputs */
> + for (n = 1; n < vc5->chip_info->clk_out_cnt; n++) {
> + idx = vc5_map_index_to_output(vc5->chip_info->model, n - 1);
> + out_name[n] = malloc(strlen(dev->name) + 5);

ditto

> + sprintf(out_name[n], "%s.out%d", dev->name, n);
> + vc5->clk_out[n].num = idx;
> + vc5->clk_out[n].vc5 = vc5;
> + ret = clk_register(&vc5->clk_out[n].hw, "versaclock-out", out_name[n],
> + vc5->clk_fod[idx].hw.dev->name);
> +
> + vc5_clk_out_set_parent(vc5, idx, 0);
> +
> + /* Fetch Clock Output configuration from DT (if specified) */
> + ret = vc5_get_output_config(dev, &vc5->clk_out[n]);
> + if (ret)
> + dev_err(dev, "failed to vc5_get_output_config()\n");
> + }
> +
> + return 0;
> +}
> +
> +static const struct udevice_id versaclock_ids[] = {
> + { .compatible = "idt,5p49v5923", .data = (ulong)&idt_5p49v5923_info },
> + { .compatible = "idt,5p49v5925", .data = (ulong)&idt_5p49v5925_info },
> + { .compatible = "idt,5p49v5933", .data = (ulong)&idt_5p49v5933_info },
> + { .compatible = "idt,5p49v5935", .data = (ulong)&idt_5p49v5935_info },
> + { .compatible = "idt,5p49v6901", .data = (ulong)&idt_5p49v6901_info },
> + { .compatible = "idt,5p49v6965", .data = (ulong)&idt_5p49v6965_info },
> + {},
> +};
> +
> +U_BOOT_DRIVER(versaclock) = {
> + .name = "versaclock",
> + .id = UCLASS_CLK,
> + .ops = &vc5_clk_ops,
> + .of_match = versaclock_ids,
> + .probe = versaclock_probe,
> + .priv_auto = sizeof(struct vc5_driver_data),
> +};
> +
> +U_BOOT_DRIVER(versaclock_mux) = {
> + .name = "versaclock-mux",
> + .id = UCLASS_CLK,
> + .ops = &vc5_mux_ops,
> +};

I'm not terribly enthusiastic about this method of instantiating clocks,
but there is nothing wrong with it. IMO you should combine clock
functions where possible. That is, if a divider has a gate child clock,
they would be combined. Though if you would like to keep the driver
structure close to the Linux driver, I don't have an objection to
keeping it as-is.

Other than the above, this LGTM.

--Sean

> +
> +U_BOOT_DRIVER(versaclock_pfd) = {
> + .name = "versaclock-pfd",
> + .id = UCLASS_CLK,
> + .ops = &vc5_pfd_ops,
> +};
> +
> +U_BOOT_DRIVER(versaclock_pll) = {
> + .name = "versaclock-pll",
> + .id = UCLASS_CLK,
> + .ops = &vc5_pll_ops,
> +};
> +
> +U_BOOT_DRIVER(versaclock_fod) = {
> + .name = "versaclock-fod",
> + .id = UCLASS_CLK,
> + .ops = &vc5_fod_ops,
> +};
> +
> +U_BOOT_DRIVER(versaclock_out) = {
> + .name = "versaclock-out",
> + .id = UCLASS_CLK,
> + .ops = &vc5_clk_out_ops,
> +};
> +
> +U_BOOT_DRIVER(versaclock_outsel) = {
> + .name = "versaclock-outsel",
> + .id = UCLASS_CLK,
> + .ops = &vc5_clk_out_sel_ops,
> +};
>