Quoting Wen He (2019-08-12 03:01:03) > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig > index 801fa1cd0321..0e6c7027d637 100644 > --- a/drivers/clk/Kconfig > +++ b/drivers/clk/Kconfig > @@ -223,6 +223,15 @@ config CLK_QORIQ > This adds the clock driver support for Freescale QorIQ platforms > using common clock framework. > > +config CLK_PLLDIG > + bool "Clock driver for LS1028A Display output" > + depends on ARCH_LAYERSCAPE && OF
Does it actually depend on either of these to build? Probabl not, so maybe just default ARCH_LAYERSCAPE && OF? Also, can your Kconfig variable be named something more specific like CLK_LS1028A_PLLDIG? > + help > + This driver support the Display output interfaces(LCD, DPHY) pixel > clocks > + of the QorIQ Layerscape LS1028A, as implemented TSMC CLN28HPM PLL. > Not all > + features of the PLL are currently supported by the driver. By > default, > + configured bypass mode with this PLL. > + > config COMMON_CLK_XGENE > bool "Clock driver for APM XGene SoC" > default ARCH_XGENE > diff --git a/drivers/clk/clk-plldig.c b/drivers/clk/clk-plldig.c > new file mode 100644 > index 000000000000..15c9bb623a70 > --- /dev/null > +++ b/drivers/clk/clk-plldig.c > @@ -0,0 +1,277 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Copyright 2019 NXP > + > +/* > + * Clock driver for LS1028A Display output interfaces(LCD, DPHY). > + * > + * Author: Wen He <wen.h...@nxp.com> > + * > + */ > + > +#include <linux/clk-provider.h> > +#include <linux/clkdev.h> PLease remove this unused include. > +#include <linux/device.h> > +#include <linux/err.h> > +#include <linux/io.h> > +#include <linux/iopoll.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> Only makes sense to include this if it's a platform device driver. > +#include <linux/slab.h> > + [...] > + > +static inline int plldig_wait_lock(struct clk_plldig *plldig) > +{ > + u32 csr; > + /* > + * Indicates whether PLL has acquired lock, if operating in bypass > + * mode, the LOCK bit will still assert when the PLL acquires lock > + * or negate when it loses lock. > + */ > + return readl_poll_timeout(plldig->regs + PLLDIG_REG_PLLSR, csr, > + csr & PLLDIG_LOCK_STATUS, 0, LOCK_TIMEOUT_US); > +} > + > +static int plldig_enable(struct clk_hw *hw) > +{ > + struct clk_plldig *data = to_clk_plldig(hw); > + u32 val; > + > + val = readl(data->regs + PLLDIG_REG_PLLFM); > + /* > + * Use Bypass mode with PLL off by default,the frequency overshoot Please add a space after comma, > + * detector output was disable. SSCG Bypass mode should be enable. > + */ > + val |= PLLDIG_SSCGBYP_ENABLE; > + writel(val, data->regs + PLLDIG_REG_PLLFM); > + [...] > + > +static int plldig_is_enabled(struct clk_hw *hw) > +{ > + struct clk_plldig *data = to_clk_plldig(hw); > + > + return (readl(data->regs + PLLDIG_REG_PLLFM) & PLLDIG_SSCGBYP_ENABLE); Please remove extraneous parenthesis. > +} > + > +/* > + * Clock configuration relationship between the PHI1 frequency(fpll_phi) and > + * the output frequency of the PLL is determined by the PLLDV, according to > + * the following equation: > + * pxclk = fpll_phi / RFDPHI1 = (pll_ref x PLLDV[MFD]) / PLLDV[RFDPHI1]. > + */ > +static bool plldig_is_valid_range(unsigned long rate, unsigned long > parent_rate, > + unsigned int *mult, unsigned int *rfdphi1, > + unsigned long *round_rate_base) > +{ > + u32 div, div_temp, mfd = PLLDIG_DEFAULE_MULT; > + unsigned long round_rate; > + > + round_rate = parent_rate * mfd; > + > + /* Range of the diliver for driving the PHI1 output clock */ divider? Not diliver, right? > + for (div = 1; div <= 63; div++) { > + /* Checking match with default mult number at first */ > + if (round_rate / div == rate) { > + *rfdphi1 = div; > + *round_rate_base = round_rate; > + *mult = mfd; > + return true; > + } > + } > + > + for (div = 1; div <= 63; div++) { > + mfd = (div * rate) / parent_rate; > + /* Range of the muliplicationthe factor applied to the /* * Please make multi line comments look like this */ > + * output reference frequency > + */ > + if ((mfd >= 10) && (mfd <= 150)) { > + div_temp = (parent_rate * mfd) / rate; > + if ((div_temp * rate) == (mfd * parent_rate)) { > + *rfdphi1 = div_temp; > + *mult = mfd; > + *round_rate_base = mfd * parent_rate; > + return true; > + } > + } > + } > + > + return false; > +} > + > +static unsigned long plldig_recalc_rate(struct clk_hw *hw, > + unsigned long parent_rate) > +{ > + struct clk_plldig *plldig = to_clk_plldig(hw); > + u32 mult, div, val; > + > + val = readl(plldig->regs + PLLDIG_REG_PLLDV); > + pr_info("%s: current configuration: 0x%x\n", clk_hw_get_name(hw), > val); Remove debug prints please. > + > + /* Check if PLL is bypassed */ > + if (val & PLLDIG_SSCGBYP_ENABLE) > + return parent_rate; > + > + /* Checkout multiplication factor divider value */ > + mult = val; > + mult = PLLDIG_GET_MULT(mult); > + > + /* Checkout divider value of the output frequency */ > + div = val; > + div = PLLDIG_GET_RFDPHI1(div); > + > + return (parent_rate * mult) / div; > +} > + > +static long plldig_round_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long *parent) > +{ > + unsigned long parent_rate = *parent; > + unsigned long round_rate; > + u32 mult = 0, rfdphi1 = 0; > + bool found = false; > + > + found = plldig_is_valid_range(rate, parent_rate, &mult, > + &rfdphi1, &round_rate); > + if (!found) { > + pr_warn("%s: unable to round rate %lu, parent rate :%lu\n", > + clk_hw_get_name(hw), rate, parent_rate); > + return 0; > + } > + > + return round_rate / rfdphi1; > +} > + > +static int plldig_set_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long parent_rate) > +{ > + struct clk_plldig *data = to_clk_plldig(hw); > + bool valid = false; > + unsigned long round_rate = 0; > + u32 rfdphi1 = 0, val, mult = 0; > + > + valid = plldig_is_valid_range(rate, parent_rate, &mult, > + &rfdphi1, &round_rate); > + if (!valid) { > + pr_warn("%s: unable to support rate %lu, parent_rate: %lu\n", > + clk_hw_get_name(hw), rate, parent_rate); > + return -EINVAL; > + } > + > + val = readl(data->regs + PLLDIG_REG_PLLDV); > + val = mult; > + rfdphi1 = PLLDIG_SET_RFDPHI1(rfdphi1); > + val |= rfdphi1; > + > + writel(val, data->regs + PLLDIG_REG_PLLDV); > + > + return plldig_wait_lock(data); > +} > + [...] > + > +struct clk_hw *_plldig_clk_init(const char *name, const char *parent_name, > + void __iomem *regs) > +{ > + struct clk_plldig *plldig; > + struct clk_hw *hw; > + struct clk_init_data init; > + int ret; > + > + plldig = kzalloc(sizeof(*plldig), GFP_KERNEL); > + if (!plldig) > + return ERR_PTR(-ENOMEM); > + > + plldig->regs = regs; > + > + init.name = name; > + init.ops = &plldig_clk_ops; > + init.parent_names = &parent_name; > + init.num_parents = 1; > + init.flags = CLK_SET_RATE_GATE; > + > + plldig->hw.init = &init; > + > + hw = &plldig->hw; > + ret = clk_hw_register(NULL, hw); > + if (ret) { > + kfree(plldig); > + hw = ERR_PTR(ret); > + } > + > + return hw; > +} > + > +static void __init plldig_clk_init(struct device_node *node) > +{ > + struct clk_hw_onecell_data *clk_data; > + struct clk_hw **clks; > + void __iomem *base; > + > + clk_data = kzalloc(struct_size(clk_data, hws, 1), > + GFP_KERNEL); > + if (!clk_data) > + return; > + > + clk_data->num = 1; > + clks = clk_data->hws; > + > + base = of_iomap(node, 0); > + WARN_ON(!base); > + > + clks[0] = _plldig_clk_init("pixel-clk", > + of_clk_get_parent_name(node, 0), base); Can you use the new way of specifying clk parents instead of calling of_clk_get-parent_name() here? It would be simpler to just indicate which index it is (I guess 0) or what the name is going to be in "clock-names" in this DT node. > + > + of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data); Why is this a #clock-cells = <1> device? It provides one clk, so presumably it can be #clock-cells = <0> and then this can use of_clk_hw_simple_get() instead. > +} > + > +CLK_OF_DECLARE(plldig_clockgen, "fsl,ls1028a-plldig", plldig_clk_init); IS there a reason why this can't be a platform driver? It would be nice to use platform device APIs.