clk-bcm2835: Read max core clock from firmware

[mirror_ubuntu-zesty-kernel.git] / drivers / clk / bcm / clk-bcm2835.c

/*
 * Copyright (C) 2010,2015 Broadcom
 * Copyright (C) 2012 Stephen Warren
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

/**
 * DOC: BCM2835 CPRMAN (clock manager for the "audio" domain)
 *
 * The clock tree on the 2835 has several levels.  There's a root
 * oscillator running at 19.2Mhz.  After the oscillator there are 5
 * PLLs, roughly divided as "camera", "ARM", "core", "DSI displays",
 * and "HDMI displays".  Those 5 PLLs each can divide their output to
 * produce up to 4 channels.  Finally, there is the level of clocks to
 * be consumed by other hardware components (like "H264" or "HDMI
 * state machine"), which divide off of some subset of the PLL
 * channels.
 *
 * All of the clocks in the tree are exposed in the DT, because the DT
 * may want to make assignments of the final layer of clocks to the
 * PLL channels, and some components of the hardware will actually
 * skip layers of the tree (for example, the pixel clock comes
 * directly from the PLLH PIX channel without using a CM_*CTL clock
 * generator).
 */

#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk.h>
#include <linux/clk/bcm2835.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <dt-bindings/clock/bcm2835.h>
#include <soc/bcm2835/raspberrypi-firmware.h>

#define CM_PASSWORD		0x5a000000

#define CM_GNRICCTL		0x000
#define CM_GNRICDIV		0x004
# define CM_DIV_FRAC_BITS	12
# define CM_DIV_FRAC_MASK	GENMASK(CM_DIV_FRAC_BITS - 1, 0)

#define CM_VPUCTL		0x008
#define CM_VPUDIV		0x00c
#define CM_SYSCTL		0x010
#define CM_SYSDIV		0x014
#define CM_PERIACTL		0x018
#define CM_PERIADIV		0x01c
#define CM_PERIICTL		0x020
#define CM_PERIIDIV		0x024
#define CM_H264CTL		0x028
#define CM_H264DIV		0x02c
#define CM_ISPCTL		0x030
#define CM_ISPDIV		0x034
#define CM_V3DCTL		0x038
#define CM_V3DDIV		0x03c
#define CM_CAM0CTL		0x040
#define CM_CAM0DIV		0x044
#define CM_CAM1CTL		0x048
#define CM_CAM1DIV		0x04c
#define CM_CCP2CTL		0x050
#define CM_CCP2DIV		0x054
#define CM_DSI0ECTL		0x058
#define CM_DSI0EDIV		0x05c
#define CM_DSI0PCTL		0x060
#define CM_DSI0PDIV		0x064
#define CM_DPICTL		0x068
#define CM_DPIDIV		0x06c
#define CM_GP0CTL		0x070
#define CM_GP0DIV		0x074
#define CM_GP1CTL		0x078
#define CM_GP1DIV		0x07c
#define CM_GP2CTL		0x080
#define CM_GP2DIV		0x084
#define CM_HSMCTL		0x088
#define CM_HSMDIV		0x08c
#define CM_OTPCTL		0x090
#define CM_OTPDIV		0x094
#define CM_PCMCTL		0x098
#define CM_PCMDIV		0x09c
#define CM_PWMCTL		0x0a0
#define CM_PWMDIV		0x0a4
#define CM_SLIMCTL		0x0a8
#define CM_SLIMDIV		0x0ac
#define CM_SMICTL		0x0b0
#define CM_SMIDIV		0x0b4
/* no definition for 0x0b8  and 0x0bc */
#define CM_TCNTCTL		0x0c0
#define CM_TCNTDIV		0x0c4
#define CM_TECCTL		0x0c8
#define CM_TECDIV		0x0cc
#define CM_TD0CTL		0x0d0
#define CM_TD0DIV		0x0d4
#define CM_TD1CTL		0x0d8
#define CM_TD1DIV		0x0dc
#define CM_TSENSCTL		0x0e0
#define CM_TSENSDIV		0x0e4
#define CM_TIMERCTL		0x0e8
#define CM_TIMERDIV		0x0ec
#define CM_UARTCTL		0x0f0
#define CM_UARTDIV		0x0f4
#define CM_VECCTL		0x0f8
#define CM_VECDIV		0x0fc
#define CM_PULSECTL		0x190
#define CM_PULSEDIV		0x194
#define CM_SDCCTL		0x1a8
#define CM_SDCDIV		0x1ac
#define CM_ARMCTL		0x1b0
#define CM_AVEOCTL		0x1b8
#define CM_AVEODIV		0x1bc
#define CM_EMMCCTL		0x1c0
#define CM_EMMCDIV		0x1c4

/* General bits for the CM_*CTL regs */
# define CM_ENABLE			BIT(4)
# define CM_KILL			BIT(5)
# define CM_GATE_BIT			6
# define CM_GATE			BIT(CM_GATE_BIT)
# define CM_BUSY			BIT(7)
# define CM_BUSYD			BIT(8)
# define CM_FRAC			BIT(9)
# define CM_SRC_SHIFT			0
# define CM_SRC_BITS			4
# define CM_SRC_MASK			0xf
# define CM_SRC_GND			0
# define CM_SRC_OSC			1
# define CM_SRC_TESTDEBUG0		2
# define CM_SRC_TESTDEBUG1		3
# define CM_SRC_PLLA_CORE		4
# define CM_SRC_PLLA_PER		4
# define CM_SRC_PLLC_CORE0		5
# define CM_SRC_PLLC_PER		5
# define CM_SRC_PLLC_CORE1		8
# define CM_SRC_PLLD_CORE		6
# define CM_SRC_PLLD_PER		6
# define CM_SRC_PLLH_AUX		7
# define CM_SRC_PLLC_CORE1		8
# define CM_SRC_PLLC_CORE2		9

#define CM_OSCCOUNT		0x100

#define CM_PLLA			0x104
# define CM_PLL_ANARST			BIT(8)
# define CM_PLLA_HOLDPER		BIT(7)
# define CM_PLLA_LOADPER		BIT(6)
# define CM_PLLA_HOLDCORE		BIT(5)
# define CM_PLLA_LOADCORE		BIT(4)
# define CM_PLLA_HOLDCCP2		BIT(3)
# define CM_PLLA_LOADCCP2		BIT(2)
# define CM_PLLA_HOLDDSI0		BIT(1)
# define CM_PLLA_LOADDSI0		BIT(0)

#define CM_PLLC			0x108
# define CM_PLLC_HOLDPER		BIT(7)
# define CM_PLLC_LOADPER		BIT(6)
# define CM_PLLC_HOLDCORE2		BIT(5)
# define CM_PLLC_LOADCORE2		BIT(4)
# define CM_PLLC_HOLDCORE1		BIT(3)
# define CM_PLLC_LOADCORE1		BIT(2)
# define CM_PLLC_HOLDCORE0		BIT(1)
# define CM_PLLC_LOADCORE0		BIT(0)

#define CM_PLLD			0x10c
# define CM_PLLD_HOLDPER		BIT(7)
# define CM_PLLD_LOADPER		BIT(6)
# define CM_PLLD_HOLDCORE		BIT(5)
# define CM_PLLD_LOADCORE		BIT(4)
# define CM_PLLD_HOLDDSI1		BIT(3)
# define CM_PLLD_LOADDSI1		BIT(2)
# define CM_PLLD_HOLDDSI0		BIT(1)
# define CM_PLLD_LOADDSI0		BIT(0)

#define CM_PLLH			0x110
# define CM_PLLH_LOADRCAL		BIT(2)
# define CM_PLLH_LOADAUX		BIT(1)
# define CM_PLLH_LOADPIX		BIT(0)

#define CM_LOCK			0x114
# define CM_LOCK_FLOCKH			BIT(12)
# define CM_LOCK_FLOCKD			BIT(11)
# define CM_LOCK_FLOCKC			BIT(10)
# define CM_LOCK_FLOCKB			BIT(9)
# define CM_LOCK_FLOCKA			BIT(8)

#define CM_EVENT		0x118
#define CM_DSI1ECTL		0x158
#define CM_DSI1EDIV		0x15c
#define CM_DSI1PCTL		0x160
#define CM_DSI1PDIV		0x164
#define CM_DFTCTL		0x168
#define CM_DFTDIV		0x16c

#define CM_PLLB			0x170
# define CM_PLLB_HOLDARM		BIT(1)
# define CM_PLLB_LOADARM		BIT(0)

#define A2W_PLLA_CTRL		0x1100
#define A2W_PLLC_CTRL		0x1120
#define A2W_PLLD_CTRL		0x1140
#define A2W_PLLH_CTRL		0x1160
#define A2W_PLLB_CTRL		0x11e0
# define A2W_PLL_CTRL_PRST_DISABLE	BIT(17)
# define A2W_PLL_CTRL_PWRDN		BIT(16)
# define A2W_PLL_CTRL_PDIV_MASK		0x000007000
# define A2W_PLL_CTRL_PDIV_SHIFT	12
# define A2W_PLL_CTRL_NDIV_MASK		0x0000003ff
# define A2W_PLL_CTRL_NDIV_SHIFT	0

#define A2W_PLLA_ANA0		0x1010
#define A2W_PLLC_ANA0		0x1030
#define A2W_PLLD_ANA0		0x1050
#define A2W_PLLH_ANA0		0x1070
#define A2W_PLLB_ANA0		0x10f0

#define A2W_PLL_KA_SHIFT	7
#define A2W_PLL_KA_MASK		GENMASK(9, 7)
#define A2W_PLL_KI_SHIFT	19
#define A2W_PLL_KI_MASK		GENMASK(21, 19)
#define A2W_PLL_KP_SHIFT	15
#define A2W_PLL_KP_MASK		GENMASK(18, 15)

#define A2W_PLLH_KA_SHIFT	19
#define A2W_PLLH_KA_MASK	GENMASK(21, 19)
#define A2W_PLLH_KI_LOW_SHIFT	22
#define A2W_PLLH_KI_LOW_MASK	GENMASK(23, 22)
#define A2W_PLLH_KI_HIGH_SHIFT	0
#define A2W_PLLH_KI_HIGH_MASK	GENMASK(0, 0)
#define A2W_PLLH_KP_SHIFT	1
#define A2W_PLLH_KP_MASK	GENMASK(4, 1)

#define A2W_XOSC_CTRL		0x1190
# define A2W_XOSC_CTRL_PLLB_ENABLE	BIT(7)
# define A2W_XOSC_CTRL_PLLA_ENABLE	BIT(6)
# define A2W_XOSC_CTRL_PLLD_ENABLE	BIT(5)
# define A2W_XOSC_CTRL_DDR_ENABLE	BIT(4)
# define A2W_XOSC_CTRL_CPR1_ENABLE	BIT(3)
# define A2W_XOSC_CTRL_USB_ENABLE	BIT(2)
# define A2W_XOSC_CTRL_HDMI_ENABLE	BIT(1)
# define A2W_XOSC_CTRL_PLLC_ENABLE	BIT(0)

#define A2W_PLLA_FRAC		0x1200
#define A2W_PLLC_FRAC		0x1220
#define A2W_PLLD_FRAC		0x1240
#define A2W_PLLH_FRAC		0x1260
#define A2W_PLLB_FRAC		0x12e0
# define A2W_PLL_FRAC_MASK		((1 << A2W_PLL_FRAC_BITS) - 1)
# define A2W_PLL_FRAC_BITS		20

#define A2W_PLL_CHANNEL_DISABLE		BIT(8)
#define A2W_PLL_DIV_BITS		8
#define A2W_PLL_DIV_SHIFT		0

#define A2W_PLLA_DSI0		0x1300
#define A2W_PLLA_CORE		0x1400
#define A2W_PLLA_PER		0x1500
#define A2W_PLLA_CCP2		0x1600

#define A2W_PLLC_CORE2		0x1320
#define A2W_PLLC_CORE1		0x1420
#define A2W_PLLC_PER		0x1520
#define A2W_PLLC_CORE0		0x1620

#define A2W_PLLD_DSI0		0x1340
#define A2W_PLLD_CORE		0x1440
#define A2W_PLLD_PER		0x1540
#define A2W_PLLD_DSI1		0x1640

#define A2W_PLLH_AUX		0x1360
#define A2W_PLLH_RCAL		0x1460
#define A2W_PLLH_PIX		0x1560
#define A2W_PLLH_STS		0x1660

#define A2W_PLLH_CTRLR		0x1960
#define A2W_PLLH_FRACR		0x1a60
#define A2W_PLLH_AUXR		0x1b60
#define A2W_PLLH_RCALR		0x1c60
#define A2W_PLLH_PIXR		0x1d60
#define A2W_PLLH_STSR		0x1e60

#define A2W_PLLB_ARM		0x13e0
#define A2W_PLLB_SP0		0x14e0
#define A2W_PLLB_SP1		0x15e0
#define A2W_PLLB_SP2		0x16e0

#define LOCK_TIMEOUT_NS		100000000
#define BCM2835_MAX_FB_RATE	1750000000u

#define VCMSG_ID_CORE_CLOCK     4

struct bcm2835_cprman {
	struct device *dev;
	void __iomem *regs;
	struct rpi_firmware *fw;
	spinlock_t regs_lock; /* spinlock for all clocks */
	const char *osc_name;

	/* Must be last */
	struct clk_hw_onecell_data onecell;
};

static inline void cprman_write(struct bcm2835_cprman *cprman, u32 reg, u32 val)
{
	writel(CM_PASSWORD | val, cprman->regs + reg);
}

static inline u32 cprman_read(struct bcm2835_cprman *cprman, u32 reg)
{
	return readl(cprman->regs + reg);
}

static int bcm2835_debugfs_regset(struct bcm2835_cprman *cprman, u32 base,
				  struct debugfs_reg32 *regs, size_t nregs,
				  struct dentry *dentry)
{
	struct dentry *regdump;
	struct debugfs_regset32 *regset;

	regset = devm_kzalloc(cprman->dev, sizeof(*regset), GFP_KERNEL);
	if (!regset)
		return -ENOMEM;

	regset->regs = regs;
	regset->nregs = nregs;
	regset->base = cprman->regs + base;

	regdump = debugfs_create_regset32("regdump", S_IRUGO, dentry,
					  regset);

	return regdump ? 0 : -ENOMEM;
}

/*
 * These are fixed clocks. They're probably not all root clocks and it may
 * be possible to turn them on and off but until this is mapped out better
 * it's the only way they can be used.
 */
void __init bcm2835_init_clocks(void)
{
	struct clk_hw *hw;
	int ret;

	hw = clk_hw_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 126000000);
	if (IS_ERR(hw))
		pr_err("apb_pclk not registered\n");

	hw = clk_hw_register_fixed_rate(NULL, "uart0_pclk", NULL, 0, 3000000);
	if (IS_ERR(hw))
		pr_err("uart0_pclk not registered\n");
	ret = clk_hw_register_clkdev(hw, NULL, "20201000.uart");
	if (ret)
		pr_err("uart0_pclk alias not registered\n");

	hw = clk_hw_register_fixed_rate(NULL, "uart1_pclk", NULL, 0, 125000000);
	if (IS_ERR(hw))
		pr_err("uart1_pclk not registered\n");
	ret = clk_hw_register_clkdev(hw, NULL, "20215000.uart");
	if (ret)
		pr_err("uart1_pclk alias not registered\n");
}

struct bcm2835_pll_data {
	const char *name;
	u32 cm_ctrl_reg;
	u32 a2w_ctrl_reg;
	u32 frac_reg;
	u32 ana_reg_base;
	u32 reference_enable_mask;
	/* Bit in CM_LOCK to indicate when the PLL has locked. */
	u32 lock_mask;

	const struct bcm2835_pll_ana_bits *ana;

	unsigned long min_rate;
	unsigned long max_rate;
	/*
	 * Highest rate for the VCO before we have to use the
	 * pre-divide-by-2.
	 */
	unsigned long max_fb_rate;
};

struct bcm2835_pll_ana_bits {
	u32 mask0;
	u32 set0;
	u32 mask1;
	u32 set1;
	u32 mask3;
	u32 set3;
	u32 fb_prediv_mask;
};

static const struct bcm2835_pll_ana_bits bcm2835_ana_default = {
	.mask0 = 0,
	.set0 = 0,
	.mask1 = (u32)~(A2W_PLL_KI_MASK | A2W_PLL_KP_MASK),
	.set1 = (2 << A2W_PLL_KI_SHIFT) | (8 << A2W_PLL_KP_SHIFT),
	.mask3 = (u32)~A2W_PLL_KA_MASK,
	.set3 = (2 << A2W_PLL_KA_SHIFT),
	.fb_prediv_mask = BIT(14),
};

static const struct bcm2835_pll_ana_bits bcm2835_ana_pllh = {
	.mask0 = (u32)~(A2W_PLLH_KA_MASK | A2W_PLLH_KI_LOW_MASK),
	.set0 = (2 << A2W_PLLH_KA_SHIFT) | (2 << A2W_PLLH_KI_LOW_SHIFT),
	.mask1 = (u32)~(A2W_PLLH_KI_HIGH_MASK | A2W_PLLH_KP_MASK),
	.set1 = (6 << A2W_PLLH_KP_SHIFT),
	.mask3 = 0,
	.set3 = 0,
	.fb_prediv_mask = BIT(11),
};

struct bcm2835_pll_divider_data {
	const char *name;
	const char *source_pll;

	u32 cm_reg;
	u32 a2w_reg;

	u32 load_mask;
	u32 hold_mask;
	u32 fixed_divider;
};

struct bcm2835_clock_data {
	const char *name;

	const char *const *parents;
	int num_mux_parents;

	/* Bitmap encoding which parents accept rate change propagation. */
	unsigned int set_rate_parent;

	u32 ctl_reg;
	u32 div_reg;

	/* Number of integer bits in the divider */
	u32 int_bits;
	/* Number of fractional bits in the divider */
	u32 frac_bits;

	u32 flags;

	bool is_vpu_clock;
	bool is_mash_clock;
};

struct bcm2835_gate_data {
	const char *name;
	const char *parent;

	u32 ctl_reg;
};

struct bcm2835_pll {
	struct clk_hw hw;
	struct bcm2835_cprman *cprman;
	const struct bcm2835_pll_data *data;
};

static int bcm2835_pll_is_on(struct clk_hw *hw)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;

	return cprman_read(cprman, data->a2w_ctrl_reg) &
		A2W_PLL_CTRL_PRST_DISABLE;
}

static void bcm2835_pll_choose_ndiv_and_fdiv(unsigned long rate,
					     unsigned long parent_rate,
					     u32 *ndiv, u32 *fdiv)
{
	u64 div;

	div = (u64)rate << A2W_PLL_FRAC_BITS;
	do_div(div, parent_rate);

	*ndiv = div >> A2W_PLL_FRAC_BITS;
	*fdiv = div & ((1 << A2W_PLL_FRAC_BITS) - 1);
}

static long bcm2835_pll_rate_from_divisors(unsigned long parent_rate,
					   u32 ndiv, u32 fdiv, u32 pdiv)
{
	u64 rate;

	if (pdiv == 0)
		return 0;

	rate = (u64)parent_rate * ((ndiv << A2W_PLL_FRAC_BITS) + fdiv);
	do_div(rate, pdiv);
	return rate >> A2W_PLL_FRAC_BITS;
}

static long bcm2835_pll_round_rate(struct clk_hw *hw, unsigned long rate,
				   unsigned long *parent_rate)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	const struct bcm2835_pll_data *data = pll->data;
	u32 ndiv, fdiv;

	rate = clamp(rate, data->min_rate, data->max_rate);

	bcm2835_pll_choose_ndiv_and_fdiv(rate, *parent_rate, &ndiv, &fdiv);

	return bcm2835_pll_rate_from_divisors(*parent_rate, ndiv, fdiv, 1);
}

static unsigned long bcm2835_pll_get_rate(struct clk_hw *hw,
					  unsigned long parent_rate)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;
	u32 a2wctrl = cprman_read(cprman, data->a2w_ctrl_reg);
	u32 ndiv, pdiv, fdiv;
	bool using_prediv;

	if (parent_rate == 0)
		return 0;

	fdiv = cprman_read(cprman, data->frac_reg) & A2W_PLL_FRAC_MASK;
	ndiv = (a2wctrl & A2W_PLL_CTRL_NDIV_MASK) >> A2W_PLL_CTRL_NDIV_SHIFT;
	pdiv = (a2wctrl & A2W_PLL_CTRL_PDIV_MASK) >> A2W_PLL_CTRL_PDIV_SHIFT;
	using_prediv = cprman_read(cprman, data->ana_reg_base + 4) &
		data->ana->fb_prediv_mask;

	if (using_prediv) {
		ndiv *= 2;
		fdiv *= 2;
	}

	return bcm2835_pll_rate_from_divisors(parent_rate, ndiv, fdiv, pdiv);
}

static void bcm2835_pll_off(struct clk_hw *hw)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;

	spin_lock(&cprman->regs_lock);
	cprman_write(cprman, data->cm_ctrl_reg,
		     cprman_read(cprman, data->cm_ctrl_reg) |
		     CM_PLL_ANARST);
	cprman_write(cprman, data->a2w_ctrl_reg,
		     cprman_read(cprman, data->a2w_ctrl_reg) |
		     A2W_PLL_CTRL_PWRDN);
	spin_unlock(&cprman->regs_lock);
}

static int bcm2835_pll_on(struct clk_hw *hw)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;
	ktime_t timeout;

	cprman_write(cprman, data->a2w_ctrl_reg,
		     cprman_read(cprman, data->a2w_ctrl_reg) &
		     ~A2W_PLL_CTRL_PWRDN);

	/* Take the PLL out of reset. */
	cprman_write(cprman, data->cm_ctrl_reg,
		     cprman_read(cprman, data->cm_ctrl_reg) & ~CM_PLL_ANARST);

	/* Wait for the PLL to lock. */
	timeout = ktime_add_ns(ktime_get(), LOCK_TIMEOUT_NS);
	while (!(cprman_read(cprman, CM_LOCK) & data->lock_mask)) {
		if (ktime_after(ktime_get(), timeout)) {
			dev_err(cprman->dev, "%s: couldn't lock PLL\n",
				clk_hw_get_name(hw));
			return -ETIMEDOUT;
		}

		cpu_relax();
	}

	return 0;
}

static void
bcm2835_pll_write_ana(struct bcm2835_cprman *cprman, u32 ana_reg_base, u32 *ana)
{
	int i;

	/*
	 * ANA register setup is done as a series of writes to
	 * ANA3-ANA0, in that order.  This lets us write all 4
	 * registers as a single cycle of the serdes interface (taking
	 * 100 xosc clocks), whereas if we were to update ana0, 1, and
	 * 3 individually through their partial-write registers, each
	 * would be their own serdes cycle.
	 */
	for (i = 3; i >= 0; i--)
		cprman_write(cprman, ana_reg_base + i * 4, ana[i]);
}

static int bcm2835_pll_set_rate(struct clk_hw *hw,
				unsigned long rate, unsigned long parent_rate)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;
	bool was_using_prediv, use_fb_prediv, do_ana_setup_first;
	u32 ndiv, fdiv, a2w_ctl;
	u32 ana[4];
	int i;

	if (rate > data->max_fb_rate) {
		use_fb_prediv = true;
		rate /= 2;
	} else {
		use_fb_prediv = false;
	}

	bcm2835_pll_choose_ndiv_and_fdiv(rate, parent_rate, &ndiv, &fdiv);

	for (i = 3; i >= 0; i--)
		ana[i] = cprman_read(cprman, data->ana_reg_base + i * 4);

	was_using_prediv = ana[1] & data->ana->fb_prediv_mask;

	ana[0] &= ~data->ana->mask0;
	ana[0] |= data->ana->set0;
	ana[1] &= ~data->ana->mask1;
	ana[1] |= data->ana->set1;
	ana[3] &= ~data->ana->mask3;
	ana[3] |= data->ana->set3;

	if (was_using_prediv && !use_fb_prediv) {
		ana[1] &= ~data->ana->fb_prediv_mask;
		do_ana_setup_first = true;
	} else if (!was_using_prediv && use_fb_prediv) {
		ana[1] |= data->ana->fb_prediv_mask;
		do_ana_setup_first = false;
	} else {
		do_ana_setup_first = true;
	}

	/* Unmask the reference clock from the oscillator. */
	cprman_write(cprman, A2W_XOSC_CTRL,
		     cprman_read(cprman, A2W_XOSC_CTRL) |
		     data->reference_enable_mask);

	if (do_ana_setup_first)
		bcm2835_pll_write_ana(cprman, data->ana_reg_base, ana);

	/* Set the PLL multiplier from the oscillator. */
	cprman_write(cprman, data->frac_reg, fdiv);

	a2w_ctl = cprman_read(cprman, data->a2w_ctrl_reg);
	a2w_ctl &= ~A2W_PLL_CTRL_NDIV_MASK;
	a2w_ctl |= ndiv << A2W_PLL_CTRL_NDIV_SHIFT;
	a2w_ctl &= ~A2W_PLL_CTRL_PDIV_MASK;
	a2w_ctl |= 1 << A2W_PLL_CTRL_PDIV_SHIFT;
	cprman_write(cprman, data->a2w_ctrl_reg, a2w_ctl);

	if (!do_ana_setup_first)
		bcm2835_pll_write_ana(cprman, data->ana_reg_base, ana);

	return 0;
}

static int bcm2835_pll_debug_init(struct clk_hw *hw,
				  struct dentry *dentry)
{
	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
	struct bcm2835_cprman *cprman = pll->cprman;
	const struct bcm2835_pll_data *data = pll->data;
	struct debugfs_reg32 *regs;

	regs = devm_kzalloc(cprman->dev, 7 * sizeof(*regs), GFP_KERNEL);
	if (!regs)
		return -ENOMEM;

	regs[0].name = "cm_ctrl";
	regs[0].offset = data->cm_ctrl_reg;
	regs[1].name = "a2w_ctrl";
	regs[1].offset = data->a2w_ctrl_reg;
	regs[2].name = "frac";
	regs[2].offset = data->frac_reg;
	regs[3].name = "ana0";
	regs[3].offset = data->ana_reg_base + 0 * 4;
	regs[4].name = "ana1";
	regs[4].offset = data->ana_reg_base + 1 * 4;
	regs[5].name = "ana2";
	regs[5].offset = data->ana_reg_base + 2 * 4;
	regs[6].name = "ana3";
	regs[6].offset = data->ana_reg_base + 3 * 4;

	return bcm2835_debugfs_regset(cprman, 0, regs, 7, dentry);
}

static const struct clk_ops bcm2835_pll_clk_ops = {
	.is_prepared = bcm2835_pll_is_on,
	.prepare = bcm2835_pll_on,
	.unprepare = bcm2835_pll_off,
	.recalc_rate = bcm2835_pll_get_rate,
	.set_rate = bcm2835_pll_set_rate,
	.round_rate = bcm2835_pll_round_rate,
	.debug_init = bcm2835_pll_debug_init,
};

struct bcm2835_pll_divider {
	struct clk_divider div;
	struct bcm2835_cprman *cprman;
	const struct bcm2835_pll_divider_data *data;
};

static struct bcm2835_pll_divider *
bcm2835_pll_divider_from_hw(struct clk_hw *hw)
{
	return container_of(hw, struct bcm2835_pll_divider, div.hw);
}

static int bcm2835_pll_divider_is_on(struct clk_hw *hw)
{
	struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
	struct bcm2835_cprman *cprman = divider->cprman;
	const struct bcm2835_pll_divider_data *data = divider->data;

	return !(cprman_read(cprman, data->a2w_reg) & A2W_PLL_CHANNEL_DISABLE);
}

static long bcm2835_pll_divider_round_rate(struct clk_hw *hw,
					   unsigned long rate,
					   unsigned long *parent_rate)
{
	return clk_divider_ops.round_rate(hw, rate, parent_rate);
}

static unsigned long bcm2835_pll_divider_get_rate(struct clk_hw *hw,
						  unsigned long parent_rate)
{
	return clk_divider_ops.recalc_rate(hw, parent_rate);
}

static void bcm2835_pll_divider_off(struct clk_hw *hw)
{
	struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
	struct bcm2835_cprman *cprman = divider->cprman;
	const struct bcm2835_pll_divider_data *data = divider->data;

	spin_lock(&cprman->regs_lock);
	cprman_write(cprman, data->cm_reg,
		     (cprman_read(cprman, data->cm_reg) &
		      ~data->load_mask) | data->hold_mask);
	cprman_write(cprman, data->a2w_reg,
		     cprman_read(cprman, data->a2w_reg) |
		     A2W_PLL_CHANNEL_DISABLE);
	spin_unlock(&cprman->regs_lock);
}

static int bcm2835_pll_divider_on(struct clk_hw *hw)
{
	struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
	struct bcm2835_cprman *cprman = divider->cprman;
	const struct bcm2835_pll_divider_data *data = divider->data;

	spin_lock(&cprman->regs_lock);
	cprman_write(cprman, data->a2w_reg,
		     cprman_read(cprman, data->a2w_reg) &
		     ~A2W_PLL_CHANNEL_DISABLE);

	cprman_write(cprman, data->cm_reg,
		     cprman_read(cprman, data->cm_reg) & ~data->hold_mask);
	spin_unlock(&cprman->regs_lock);

	return 0;
}

static int bcm2835_pll_divider_set_rate(struct clk_hw *hw,
					unsigned long rate,
					unsigned long parent_rate)
{
	struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
	struct bcm2835_cprman *cprman = divider->cprman;
	const struct bcm2835_pll_divider_data *data = divider->data;
	u32 cm, div, max_div = 1 << A2W_PLL_DIV_BITS;

	div = DIV_ROUND_UP_ULL(parent_rate, rate);

	div = min(div, max_div);
	if (div == max_div)
		div = 0;

	cprman_write(cprman, data->a2w_reg, div);
	cm = cprman_read(cprman, data->cm_reg);
	cprman_write(cprman, data->cm_reg, cm | data->load_mask);
	cprman_write(cprman, data->cm_reg, cm & ~data->load_mask);

	return 0;
}

static int bcm2835_pll_divider_debug_init(struct clk_hw *hw,
					  struct dentry *dentry)
{
	struct bcm2835_pll_divider *divider = bcm2835_pll_divider_from_hw(hw);
	struct bcm2835_cprman *cprman = divider->cprman;
	const struct bcm2835_pll_divider_data *data = divider->data;
	struct debugfs_reg32 *regs;

	regs = devm_kzalloc(cprman->dev, 7 * sizeof(*regs), GFP_KERNEL);
	if (!regs)
		return -ENOMEM;

	regs[0].name = "cm";
	regs[0].offset = data->cm_reg;
	regs[1].name = "a2w";
	regs[1].offset = data->a2w_reg;

	return bcm2835_debugfs_regset(cprman, 0, regs, 2, dentry);
}

static const struct clk_ops bcm2835_pll_divider_clk_ops = {
	.is_prepared = bcm2835_pll_divider_is_on,
	.prepare = bcm2835_pll_divider_on,
	.unprepare = bcm2835_pll_divider_off,
	.recalc_rate = bcm2835_pll_divider_get_rate,
	.set_rate = bcm2835_pll_divider_set_rate,
	.round_rate = bcm2835_pll_divider_round_rate,
	.debug_init = bcm2835_pll_divider_debug_init,
};

/*
 * The CM dividers do fixed-point division, so we can't use the
 * generic integer divider code like the PLL dividers do (and we can't
 * fake it by having some fixed shifts preceding it in the clock tree,
 * because we'd run out of bits in a 32-bit unsigned long).
 */
struct bcm2835_clock {
	struct clk_hw hw;
	struct bcm2835_cprman *cprman;
	const struct bcm2835_clock_data *data;
};

static struct bcm2835_clock *bcm2835_clock_from_hw(struct clk_hw *hw)
{
	return container_of(hw, struct bcm2835_clock, hw);
}

static int bcm2835_clock_is_on(struct clk_hw *hw)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;

	return (cprman_read(cprman, data->ctl_reg) & CM_ENABLE) != 0;
}

static u32 bcm2835_clock_choose_div(struct clk_hw *hw,
				    unsigned long rate,
				    unsigned long parent_rate,
				    bool round_up)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	const struct bcm2835_clock_data *data = clock->data;
	u32 unused_frac_mask =
		GENMASK(CM_DIV_FRAC_BITS - data->frac_bits, 0) >> 1;
	u64 temp = (u64)parent_rate << CM_DIV_FRAC_BITS;
	u64 rem;
	u32 div, mindiv, maxdiv;

	rem = do_div(temp, rate);
	div = temp;

	/* Round up and mask off the unused bits */
	if (round_up && ((div & unused_frac_mask) != 0 || rem != 0))
		div += unused_frac_mask + 1;
	div &= ~unused_frac_mask;

	/* different clamping limits apply for a mash clock */
	if (data->is_mash_clock) {
		/* clamp to min divider of 2 */
		mindiv = 2 << CM_DIV_FRAC_BITS;
		/* clamp to the highest possible integer divider */
		maxdiv = (BIT(data->int_bits) - 1) << CM_DIV_FRAC_BITS;
	} else {
		/* clamp to min divider of 1 */
		mindiv = 1 << CM_DIV_FRAC_BITS;
		/* clamp to the highest possible fractional divider */
		maxdiv = GENMASK(data->int_bits + CM_DIV_FRAC_BITS - 1,
				 CM_DIV_FRAC_BITS - data->frac_bits);
	}

	/* apply the clamping  limits */
	div = max_t(u32, div, mindiv);
	div = min_t(u32, div, maxdiv);

	return div;
}

static long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
					    unsigned long parent_rate,
					    u32 div)
{
	const struct bcm2835_clock_data *data = clock->data;
	u64 temp;

	/*
	 * The divisor is a 12.12 fixed point field, but only some of
	 * the bits are populated in any given clock.
	 */
	div >>= CM_DIV_FRAC_BITS - data->frac_bits;
	div &= (1 << (data->int_bits + data->frac_bits)) - 1;

	if (div == 0)
		return 0;

	temp = (u64)parent_rate << data->frac_bits;

	do_div(temp, div);

	return temp;
}

static unsigned long bcm2835_clock_get_rate(struct clk_hw *hw,
					    unsigned long parent_rate)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	u32 div = cprman_read(cprman, data->div_reg);

	return bcm2835_clock_rate_from_divisor(clock, parent_rate, div);
}

static unsigned long bcm2835_clock_get_rate_vpu(struct clk_hw *hw,
						unsigned long parent_rate)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;

	if (cprman->fw) {
		struct {
			u32 id;
			u32 val;
		} packet;

		packet.id = VCMSG_ID_CORE_CLOCK;
		packet.val = 0;

		if (!rpi_firmware_property(cprman->fw,
					   RPI_FIRMWARE_GET_MAX_CLOCK_RATE,
					   &packet, sizeof(packet)))
			return packet.val;
	}

	return bcm2835_clock_get_rate(hw, parent_rate);
}

static void bcm2835_clock_wait_busy(struct bcm2835_clock *clock)
{
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	ktime_t timeout = ktime_add_ns(ktime_get(), LOCK_TIMEOUT_NS);

	while (cprman_read(cprman, data->ctl_reg) & CM_BUSY) {
		if (ktime_after(ktime_get(), timeout)) {
			dev_err(cprman->dev, "%s: couldn't lock PLL\n",
				clk_hw_get_name(&clock->hw));
			return;
		}
		cpu_relax();
	}
}

static void bcm2835_clock_off(struct clk_hw *hw)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;

	spin_lock(&cprman->regs_lock);
	cprman_write(cprman, data->ctl_reg,
		     cprman_read(cprman, data->ctl_reg) & ~CM_ENABLE);
	spin_unlock(&cprman->regs_lock);

	/* BUSY will remain high until the divider completes its cycle. */
	bcm2835_clock_wait_busy(clock);
}

static int bcm2835_clock_on(struct clk_hw *hw)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;

	spin_lock(&cprman->regs_lock);
	cprman_write(cprman, data->ctl_reg,
		     cprman_read(cprman, data->ctl_reg) |
		     CM_ENABLE |
		     CM_GATE);
	spin_unlock(&cprman->regs_lock);

	return 0;
}

static int bcm2835_clock_set_rate(struct clk_hw *hw,
				  unsigned long rate, unsigned long parent_rate)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	u32 div = bcm2835_clock_choose_div(hw, rate, parent_rate, false);
	u32 ctl;

	spin_lock(&cprman->regs_lock);

	/*
	 * Setting up frac support
	 *
	 * In principle it is recommended to stop/start the clock first,
	 * but as we set CLK_SET_RATE_GATE during registration of the
	 * clock this requirement should be take care of by the
	 * clk-framework.
	 */
	ctl = cprman_read(cprman, data->ctl_reg) & ~CM_FRAC;
	ctl |= (div & CM_DIV_FRAC_MASK) ? CM_FRAC : 0;
	cprman_write(cprman, data->ctl_reg, ctl);

	cprman_write(cprman, data->div_reg, div);

	spin_unlock(&cprman->regs_lock);

	return 0;
}

static bool
bcm2835_clk_is_pllc(struct clk_hw *hw)
{
	if (!hw)
		return false;

	return strncmp(clk_hw_get_name(hw), "pllc", 4) == 0;
}

static unsigned long bcm2835_clock_choose_div_and_prate(struct clk_hw *hw,
							int parent_idx,
							unsigned long rate,
							u32 *div,
							unsigned long *prate)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	unsigned long best_rate = 0;
	u32 curdiv, mindiv, maxdiv;
	struct clk_hw *parent;

	parent = clk_hw_get_parent_by_index(hw, parent_idx);

	if (!(BIT(parent_idx) & data->set_rate_parent)) {
		*prate = clk_hw_get_rate(parent);
		*div = bcm2835_clock_choose_div(hw, rate, *prate, true);

		return bcm2835_clock_rate_from_divisor(clock, *prate,
						       *div);
	}

	if (data->frac_bits)
		dev_warn(cprman->dev,
			"frac bits are not used when propagating rate change");

	/* clamp to min divider of 2 if we're dealing with a mash clock */
	mindiv = data->is_mash_clock ? 2 : 1;
	maxdiv = BIT(data->int_bits) - 1;

	/* TODO: Be smart, and only test a subset of the available divisors. */
	for (curdiv = mindiv; curdiv <= maxdiv; curdiv++) {
		unsigned long tmp_rate;

		tmp_rate = clk_hw_round_rate(parent, rate * curdiv);
		tmp_rate /= curdiv;
		if (curdiv == mindiv ||
		    (tmp_rate > best_rate && tmp_rate <= rate))
			best_rate = tmp_rate;

		if (best_rate == rate)
			break;
	}

	*div = curdiv << CM_DIV_FRAC_BITS;
	*prate = curdiv * best_rate;

	return best_rate;
}

static int bcm2835_clock_determine_rate(struct clk_hw *hw,
					struct clk_rate_request *req)
{
	struct clk_hw *parent, *best_parent = NULL;
	bool current_parent_is_pllc;
	unsigned long rate, best_rate = 0;
	unsigned long prate, best_prate = 0;
	size_t i;
	u32 div;

	current_parent_is_pllc = bcm2835_clk_is_pllc(clk_hw_get_parent(hw));

	/*
	 * Select parent clock that results in the closest but lower rate
	 */
	for (i = 0; i < clk_hw_get_num_parents(hw); ++i) {
		parent = clk_hw_get_parent_by_index(hw, i);
		if (!parent)
			continue;

		/*
		 * Don't choose a PLLC-derived clock as our parent
		 * unless it had been manually set that way.  PLLC's
		 * frequency gets adjusted by the firmware due to
		 * over-temp or under-voltage conditions, without
		 * prior notification to our clock consumer.
		 */
		if (bcm2835_clk_is_pllc(parent) && !current_parent_is_pllc)
			continue;

		rate = bcm2835_clock_choose_div_and_prate(hw, i, req->rate,
							  &div, &prate);
		if (rate > best_rate && rate <= req->rate) {
			best_parent = parent;
			best_prate = prate;
			best_rate = rate;
		}
	}

	if (!best_parent)
		return -EINVAL;

	req->best_parent_hw = best_parent;
	req->best_parent_rate = best_prate;

	req->rate = best_rate;

	return 0;
}

static int bcm2835_clock_set_parent(struct clk_hw *hw, u8 index)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	u8 src = (index << CM_SRC_SHIFT) & CM_SRC_MASK;

	cprman_write(cprman, data->ctl_reg, src);
	return 0;
}

static u8 bcm2835_clock_get_parent(struct clk_hw *hw)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;
	u32 src = cprman_read(cprman, data->ctl_reg);

	return (src & CM_SRC_MASK) >> CM_SRC_SHIFT;
}

static struct debugfs_reg32 bcm2835_debugfs_clock_reg32[] = {
	{
		.name = "ctl",
		.offset = 0,
	},
	{
		.name = "div",
		.offset = 4,
	},
};

static int bcm2835_clock_debug_init(struct clk_hw *hw,
				    struct dentry *dentry)
{
	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
	struct bcm2835_cprman *cprman = clock->cprman;
	const struct bcm2835_clock_data *data = clock->data;

	return bcm2835_debugfs_regset(
		cprman, data->ctl_reg,
		bcm2835_debugfs_clock_reg32,
		ARRAY_SIZE(bcm2835_debugfs_clock_reg32),
		dentry);
}

static const struct clk_ops bcm2835_clock_clk_ops = {
	.is_prepared = bcm2835_clock_is_on,
	.prepare = bcm2835_clock_on,
	.unprepare = bcm2835_clock_off,
	.recalc_rate = bcm2835_clock_get_rate,
	.set_rate = bcm2835_clock_set_rate,
	.determine_rate = bcm2835_clock_determine_rate,
	.set_parent = bcm2835_clock_set_parent,
	.get_parent = bcm2835_clock_get_parent,
	.debug_init = bcm2835_clock_debug_init,
};

static int bcm2835_vpu_clock_is_on(struct clk_hw *hw)
{
	return true;
}

/*
 * The VPU clock can never be disabled (it doesn't have an ENABLE
 * bit), so it gets its own set of clock ops.
 */
static const struct clk_ops bcm2835_vpu_clock_clk_ops = {
	.is_prepared = bcm2835_vpu_clock_is_on,
	.recalc_rate = bcm2835_clock_get_rate_vpu,
	.set_rate = bcm2835_clock_set_rate,
	.determine_rate = bcm2835_clock_determine_rate,
	.set_parent = bcm2835_clock_set_parent,
	.get_parent = bcm2835_clock_get_parent,
	.debug_init = bcm2835_clock_debug_init,
};

static bool bcm2835_clk_is_claimed(const char *name);

static struct clk_hw *bcm2835_register_pll(struct bcm2835_cprman *cprman,
					   const struct bcm2835_pll_data *data)
{
	struct bcm2835_pll *pll;
	struct clk_init_data init;
	int ret;

	memset(&init, 0, sizeof(init));

	/* All of the PLLs derive from the external oscillator. */
	init.parent_names = &cprman->osc_name;
	init.num_parents = 1;
	init.name = data->name;
	init.ops = &bcm2835_pll_clk_ops;
	init.flags = CLK_IGNORE_UNUSED;

	if (!bcm2835_clk_is_claimed(data->name))
		init.flags |= CLK_IS_CRITICAL;

	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
	if (!pll)
		return NULL;

	pll->cprman = cprman;
	pll->data = data;
	pll->hw.init = &init;

	ret = devm_clk_hw_register(cprman->dev, &pll->hw);
	if (ret)
		return NULL;
	return &pll->hw;
}

static struct clk_hw *
bcm2835_register_pll_divider(struct bcm2835_cprman *cprman,
			     const struct bcm2835_pll_divider_data *data)
{
	struct bcm2835_pll_divider *divider;
	struct clk_init_data init;
	const char *divider_name;
	int ret;

	if (data->fixed_divider != 1) {
		divider_name = devm_kasprintf(cprman->dev, GFP_KERNEL,
					      "%s_prediv", data->name);
		if (!divider_name)
			return NULL;
	} else {
		divider_name = data->name;
	}

	memset(&init, 0, sizeof(init));

	init.parent_names = &data->source_pll;
	init.num_parents = 1;
	init.name = divider_name;
	init.ops = &bcm2835_pll_divider_clk_ops;
	init.flags = CLK_SET_RATE_PARENT | CLK_IGNORE_UNUSED;

	divider = devm_kzalloc(cprman->dev, sizeof(*divider), GFP_KERNEL);
	if (!divider)
		return NULL;

	divider->div.reg = cprman->regs + data->a2w_reg;
	divider->div.shift = A2W_PLL_DIV_SHIFT;
	divider->div.width = A2W_PLL_DIV_BITS;
	divider->div.flags = CLK_DIVIDER_MAX_AT_ZERO;
	divider->div.lock = &cprman->regs_lock;
	divider->div.hw.init = &init;
	divider->div.table = NULL;

	if (!(cprman_read(cprman, data->cm_reg) & data->hold_mask)) {
		if (!bcm2835_clk_is_claimed(data->source_pll))
			init.flags |= CLK_IS_CRITICAL;
		if (!bcm2835_clk_is_claimed(data->name))
			divider->div.flags |= CLK_IS_CRITICAL;
	}

	divider->cprman = cprman;
	divider->data = data;

	ret = devm_clk_hw_register(cprman->dev, &divider->div.hw);
	if (ret)
		return ERR_PTR(ret);

	/*
	 * PLLH's channels have a fixed divide by 10 afterwards, which
	 * is what our consumers are actually using.
	 */
	if (data->fixed_divider != 1) {
		return clk_hw_register_fixed_factor(cprman->dev, data->name,
						    divider_name,
						    CLK_SET_RATE_PARENT,
						    1,
						    data->fixed_divider);
	}

	return &divider->div.hw;
}

static struct clk_hw *bcm2835_register_clock(struct bcm2835_cprman *cprman,
					  const struct bcm2835_clock_data *data)
{
	struct bcm2835_clock *clock;
	struct clk_init_data init;
	const char *parents[1 << CM_SRC_BITS];
	size_t i;
	int ret;

	/*
	 * Replace our "xosc" references with the oscillator's
	 * actual name.
	 */
	for (i = 0; i < data->num_mux_parents; i++) {
		if (strcmp(data->parents[i], "xosc") == 0)
			parents[i] = cprman->osc_name;
		else
			parents[i] = data->parents[i];
	}

	memset(&init, 0, sizeof(init));
	init.parent_names = parents;
	init.num_parents = data->num_mux_parents;
	init.name = data->name;
	init.flags = data->flags | CLK_IGNORE_UNUSED;

	/*
	 * Pass the CLK_SET_RATE_PARENT flag if we are allowed to propagate
	 * rate changes on at least of the parents.
	 */
	if (data->set_rate_parent)
		init.flags |= CLK_SET_RATE_PARENT;

	if (data->is_vpu_clock) {
		init.ops = &bcm2835_vpu_clock_clk_ops;
	} else {
		init.ops = &bcm2835_clock_clk_ops;
		init.flags |= CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;

		/* If the clock wasn't actually enabled at boot, it's not
		 * critical.
		 */
		if (!(cprman_read(cprman, data->ctl_reg) & CM_ENABLE))
			init.flags &= ~CLK_IS_CRITICAL;
	}

	clock = devm_kzalloc(cprman->dev, sizeof(*clock), GFP_KERNEL);
	if (!clock)
		return NULL;

	clock->cprman = cprman;
	clock->data = data;
	clock->hw.init = &init;

	ret = devm_clk_hw_register(cprman->dev, &clock->hw);
	if (ret)
		return ERR_PTR(ret);
	return &clock->hw;
}

static struct clk *bcm2835_register_gate(struct bcm2835_cprman *cprman,
					 const struct bcm2835_gate_data *data)
{
	return clk_register_gate(cprman->dev, data->name, data->parent,
				 CLK_IGNORE_UNUSED | CLK_SET_RATE_GATE,
				 cprman->regs + data->ctl_reg,
				 CM_GATE_BIT, 0, &cprman->regs_lock);
}

typedef struct clk_hw *(*bcm2835_clk_register)(struct bcm2835_cprman *cprman,
					       const void *data);
struct bcm2835_clk_desc {
	bcm2835_clk_register clk_register;
	const void *data;
};

/* assignment helper macros for different clock types */
#define _REGISTER(f, ...) { .clk_register = (bcm2835_clk_register)f, \
			    .data = __VA_ARGS__ }
#define REGISTER_PLL(...)	_REGISTER(&bcm2835_register_pll,	\
					  &(struct bcm2835_pll_data)	\
					  {__VA_ARGS__})
#define REGISTER_PLL_DIV(...)	_REGISTER(&bcm2835_register_pll_divider, \
					  &(struct bcm2835_pll_divider_data) \
					  {__VA_ARGS__})
#define REGISTER_CLK(...)	_REGISTER(&bcm2835_register_clock,	\
					  &(struct bcm2835_clock_data)	\
					  {__VA_ARGS__})
#define REGISTER_GATE(...)	_REGISTER(&bcm2835_register_gate,	\
					  &(struct bcm2835_gate_data)	\
					  {__VA_ARGS__})

/* parent mux arrays plus helper macros */

/* main oscillator parent mux */
static const char *const bcm2835_clock_osc_parents[] = {
	"gnd",
	"xosc",
	"testdebug0",
	"testdebug1"
};

#define REGISTER_OSC_CLK(...)	REGISTER_CLK(				\
	.num_mux_parents = ARRAY_SIZE(bcm2835_clock_osc_parents),	\
	.parents = bcm2835_clock_osc_parents,				\
	__VA_ARGS__)

/* main peripherial parent mux */
static const char *const bcm2835_clock_per_parents[] = {
	"gnd",
	"xosc",
	"testdebug0",
	"testdebug1",
	"plla_per",
	"pllc_per",
	"plld_per",
	"pllh_aux",
};

#define REGISTER_PER_CLK(...)	REGISTER_CLK(				\
	.num_mux_parents = ARRAY_SIZE(bcm2835_clock_per_parents),	\
	.parents = bcm2835_clock_per_parents,				\
	__VA_ARGS__)

/* main vpu parent mux */
static const char *const bcm2835_clock_vpu_parents[] = {
	"gnd",
	"xosc",
	"testdebug0",
	"testdebug1",
	"plla_core",
	"pllc_core0",
	"plld_core",
	"pllh_aux",
	"pllc_core1",
	"pllc_core2",
};

#define REGISTER_VPU_CLK(...)	REGISTER_CLK(				\
	.num_mux_parents = ARRAY_SIZE(bcm2835_clock_vpu_parents),	\
	.parents = bcm2835_clock_vpu_parents,				\
	__VA_ARGS__)

/*
 * the real definition of all the pll, pll_dividers and clocks
 * these make use of the above REGISTER_* macros
 */
static const struct bcm2835_clk_desc clk_desc_array[] = {
	/* the PLL + PLL dividers */

	/*
	 * PLLA is the auxiliary PLL, used to drive the CCP2
	 * (Compact Camera Port 2) transmitter clock.
	 *
	 * It is in the PX LDO power domain, which is on when the
	 * AUDIO domain is on.
	 */
	[BCM2835_PLLA]		= REGISTER_PLL(
		.name = "plla",
		.cm_ctrl_reg = CM_PLLA,
		.a2w_ctrl_reg = A2W_PLLA_CTRL,
		.frac_reg = A2W_PLLA_FRAC,
		.ana_reg_base = A2W_PLLA_ANA0,
		.reference_enable_mask = A2W_XOSC_CTRL_PLLA_ENABLE,
		.lock_mask = CM_LOCK_FLOCKA,

		.ana = &bcm2835_ana_default,

		.min_rate = 600000000u,
		.max_rate = 2400000000u,
		.max_fb_rate = BCM2835_MAX_FB_RATE),
	[BCM2835_PLLA_CORE]	= REGISTER_PLL_DIV(
		.name = "plla_core",
		.source_pll = "plla",
		.cm_reg = CM_PLLA,
		.a2w_reg = A2W_PLLA_CORE,
		.load_mask = CM_PLLA_LOADCORE,
		.hold_mask = CM_PLLA_HOLDCORE,
		.fixed_divider = 1),
	[BCM2835_PLLA_PER]	= REGISTER_PLL_DIV(
		.name = "plla_per",
		.source_pll = "plla",
		.cm_reg = CM_PLLA,
		.a2w_reg = A2W_PLLA_PER,
		.load_mask = CM_PLLA_LOADPER,
		.hold_mask = CM_PLLA_HOLDPER,
		.fixed_divider = 1),
	[BCM2835_PLLA_DSI0]	= REGISTER_PLL_DIV(
		.name = "plla_dsi0",
		.source_pll = "plla",
		.cm_reg = CM_PLLA,
		.a2w_reg = A2W_PLLA_DSI0,
		.load_mask = CM_PLLA_LOADDSI0,
		.hold_mask = CM_PLLA_HOLDDSI0,
		.fixed_divider = 1),
	[BCM2835_PLLA_CCP2]	= REGISTER_PLL_DIV(
		.name = "plla_ccp2",
		.source_pll = "plla",
		.cm_reg = CM_PLLA,
		.a2w_reg = A2W_PLLA_CCP2,
		.load_mask = CM_PLLA_LOADCCP2,
		.hold_mask = CM_PLLA_HOLDCCP2,
		.fixed_divider = 1),

	/* PLLB is used for the ARM's clock. */
	[BCM2835_PLLB]		= REGISTER_PLL(
		.name = "pllb",
		.cm_ctrl_reg = CM_PLLB,
		.a2w_ctrl_reg = A2W_PLLB_CTRL,
		.frac_reg = A2W_PLLB_FRAC,
		.ana_reg_base = A2W_PLLB_ANA0,
		.reference_enable_mask = A2W_XOSC_CTRL_PLLB_ENABLE,
		.lock_mask = CM_LOCK_FLOCKB,

		.ana = &bcm2835_ana_default,

		.min_rate = 600000000u,
		.max_rate = 3000000000u,
		.max_fb_rate = BCM2835_MAX_FB_RATE),
	[BCM2835_PLLB_ARM]	= REGISTER_PLL_DIV(
		.name = "pllb_arm",
		.source_pll = "pllb",
		.cm_reg = CM_PLLB,
		.a2w_reg = A2W_PLLB_ARM,
		.load_mask = CM_PLLB_LOADARM,
		.hold_mask = CM_PLLB_HOLDARM,
		.fixed_divider = 1),

	/*
	 * PLLC is the core PLL, used to drive the core VPU clock.
	 *
	 * It is in the PX LDO power domain, which is on when the
	 * AUDIO domain is on.
	 */
	[BCM2835_PLLC]		= REGISTER_PLL(
		.name = "pllc",
		.cm_ctrl_reg = CM_PLLC,
		.a2w_ctrl_reg = A2W_PLLC_CTRL,
		.frac_reg = A2W_PLLC_FRAC,
		.ana_reg_base = A2W_PLLC_ANA0,
		.reference_enable_mask = A2W_XOSC_CTRL_PLLC_ENABLE,
		.lock_mask = CM_LOCK_FLOCKC,

		.ana = &bcm2835_ana_default,

		.min_rate = 600000000u,
		.max_rate = 3000000000u,
		.max_fb_rate = BCM2835_MAX_FB_RATE),
	[BCM2835_PLLC_CORE0]	= REGISTER_PLL_DIV(
		.name = "pllc_core0",
		.source_pll = "pllc",
		.cm_reg = CM_PLLC,
		.a2w_reg = A2W_PLLC_CORE0,
		.load_mask = CM_PLLC_LOADCORE0,
		.hold_mask = CM_PLLC_HOLDCORE0,
		.fixed_divider = 1),
	[BCM2835_PLLC_CORE1]	= REGISTER_PLL_DIV(
		.name = "pllc_core1",
		.source_pll = "pllc",
		.cm_reg = CM_PLLC,
		.a2w_reg = A2W_PLLC_CORE1,
		.load_mask = CM_PLLC_LOADCORE1,
		.hold_mask = CM_PLLC_HOLDCORE1,
		.fixed_divider = 1),
	[BCM2835_PLLC_CORE2]	= REGISTER_PLL_DIV(
		.name = "pllc_core2",
		.source_pll = "pllc",
		.cm_reg = CM_PLLC,
		.a2w_reg = A2W_PLLC_CORE2,
		.load_mask = CM_PLLC_LOADCORE2,
		.hold_mask = CM_PLLC_HOLDCORE2,
		.fixed_divider = 1),
	[BCM2835_PLLC_PER]	= REGISTER_PLL_DIV(
		.name = "pllc_per",
		.source_pll = "pllc",
		.cm_reg = CM_PLLC,
		.a2w_reg = A2W_PLLC_PER,
		.load_mask = CM_PLLC_LOADPER,
		.hold_mask = CM_PLLC_HOLDPER,
		.fixed_divider = 1),

	/*
	 * PLLD is the display PLL, used to drive DSI display panels.
	 *
	 * It is in the PX LDO power domain, which is on when the
	 * AUDIO domain is on.
	 */
	[BCM2835_PLLD]		= REGISTER_PLL(
		.name = "plld",
		.cm_ctrl_reg = CM_PLLD,
		.a2w_ctrl_reg = A2W_PLLD_CTRL,
		.frac_reg = A2W_PLLD_FRAC,
		.ana_reg_base = A2W_PLLD_ANA0,
		.reference_enable_mask = A2W_XOSC_CTRL_DDR_ENABLE,
		.lock_mask = CM_LOCK_FLOCKD,

		.ana = &bcm2835_ana_default,

		.min_rate = 600000000u,
		.max_rate = 2400000000u,
		.max_fb_rate = BCM2835_MAX_FB_RATE),
	[BCM2835_PLLD_CORE]	= REGISTER_PLL_DIV(
		.name = "plld_core",
		.source_pll = "plld",
		.cm_reg = CM_PLLD,
		.a2w_reg = A2W_PLLD_CORE,
		.load_mask = CM_PLLD_LOADCORE,
		.hold_mask = CM_PLLD_HOLDCORE,
		.fixed_divider = 1),
	[BCM2835_PLLD_PER]	= REGISTER_PLL_DIV(
		.name = "plld_per",
		.source_pll = "plld",
		.cm_reg = CM_PLLD,
		.a2w_reg = A2W_PLLD_PER,
		.load_mask = CM_PLLD_LOADPER,
		.hold_mask = CM_PLLD_HOLDPER,
		.fixed_divider = 1),
	[BCM2835_PLLD_DSI0]	= REGISTER_PLL_DIV(
		.name = "plld_dsi0",
		.source_pll = "plld",
		.cm_reg = CM_PLLD,
		.a2w_reg = A2W_PLLD_DSI0,
		.load_mask = CM_PLLD_LOADDSI0,
		.hold_mask = CM_PLLD_HOLDDSI0,
		.fixed_divider = 1),
	[BCM2835_PLLD_DSI1]	= REGISTER_PLL_DIV(
		.name = "plld_dsi1",
		.source_pll = "plld",
		.cm_reg = CM_PLLD,
		.a2w_reg = A2W_PLLD_DSI1,
		.load_mask = CM_PLLD_LOADDSI1,
		.hold_mask = CM_PLLD_HOLDDSI1,
		.fixed_divider = 1),

	/*
	 * PLLH is used to supply the pixel clock or the AUX clock for the
	 * TV encoder.
	 *
	 * It is in the HDMI power domain.
	 */
	[BCM2835_PLLH]		= REGISTER_PLL(
		"pllh",
		.cm_ctrl_reg = CM_PLLH,
		.a2w_ctrl_reg = A2W_PLLH_CTRL,
		.frac_reg = A2W_PLLH_FRAC,
		.ana_reg_base = A2W_PLLH_ANA0,
		.reference_enable_mask = A2W_XOSC_CTRL_PLLC_ENABLE,
		.lock_mask = CM_LOCK_FLOCKH,

		.ana = &bcm2835_ana_pllh,

		.min_rate = 600000000u,
		.max_rate = 3000000000u,
		.max_fb_rate = BCM2835_MAX_FB_RATE),
	[BCM2835_PLLH_RCAL]	= REGISTER_PLL_DIV(
		.name = "pllh_rcal",
		.source_pll = "pllh",
		.cm_reg = CM_PLLH,
		.a2w_reg = A2W_PLLH_RCAL,
		.load_mask = CM_PLLH_LOADRCAL,
		.hold_mask = 0,
		.fixed_divider = 10),
	[BCM2835_PLLH_AUX]	= REGISTER_PLL_DIV(
		.name = "pllh_aux",
		.source_pll = "pllh",
		.cm_reg = CM_PLLH,
		.a2w_reg = A2W_PLLH_AUX,
		.load_mask = CM_PLLH_LOADAUX,
		.hold_mask = 0,
		.fixed_divider = 1),
	[BCM2835_PLLH_PIX]	= REGISTER_PLL_DIV(
		.name = "pllh_pix",
		.source_pll = "pllh",
		.cm_reg = CM_PLLH,
		.a2w_reg = A2W_PLLH_PIX,
		.load_mask = CM_PLLH_LOADPIX,
		.hold_mask = 0,
		.fixed_divider = 10),

	/* the clocks */

	/* clocks with oscillator parent mux */

	/* One Time Programmable Memory clock.  Maximum 10Mhz. */
	[BCM2835_CLOCK_OTP]	= REGISTER_OSC_CLK(
		.name = "otp",
		.ctl_reg = CM_OTPCTL,
		.div_reg = CM_OTPDIV,
		.int_bits = 4,
		.frac_bits = 0),
	/*
	 * Used for a 1Mhz clock for the system clocksource, and also used
	 * bythe watchdog timer and the camera pulse generator.
	 */
	[BCM2835_CLOCK_TIMER]	= REGISTER_OSC_CLK(
		.name = "timer",
		.ctl_reg = CM_TIMERCTL,
		.div_reg = CM_TIMERDIV,
		.int_bits = 6,
		.frac_bits = 12),
	/*
	 * Clock for the temperature sensor.
	 * Generally run at 2Mhz, max 5Mhz.
	 */
	[BCM2835_CLOCK_TSENS]	= REGISTER_OSC_CLK(
		.name = "tsens",
		.ctl_reg = CM_TSENSCTL,
		.div_reg = CM_TSENSDIV,
		.int_bits = 5,
		.frac_bits = 0),
	[BCM2835_CLOCK_TEC]	= REGISTER_OSC_CLK(
		.name = "tec",
		.ctl_reg = CM_TECCTL,
		.div_reg = CM_TECDIV,
		.int_bits = 6,
		.frac_bits = 0),

	/* clocks with vpu parent mux */
	[BCM2835_CLOCK_H264]	= REGISTER_VPU_CLK(
		.name = "h264",
		.ctl_reg = CM_H264CTL,
		.div_reg = CM_H264DIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_ISP]	= REGISTER_VPU_CLK(
		.name = "isp",
		.ctl_reg = CM_ISPCTL,
		.div_reg = CM_ISPDIV,
		.int_bits = 4,
		.frac_bits = 8),

	/*
	 * Secondary SDRAM clock.  Used for low-voltage modes when the PLL
	 * in the SDRAM controller can't be used.
	 */
	[BCM2835_CLOCK_SDRAM]	= REGISTER_VPU_CLK(
		.name = "sdram",
		.ctl_reg = CM_SDCCTL,
		.div_reg = CM_SDCDIV,
		.int_bits = 6,
		.frac_bits = 0),
	[BCM2835_CLOCK_V3D]	= REGISTER_VPU_CLK(
		.name = "v3d",
		.ctl_reg = CM_V3DCTL,
		.div_reg = CM_V3DDIV,
		.int_bits = 4,
		.frac_bits = 8),
	/*
	 * VPU clock.  This doesn't have an enable bit, since it drives
	 * the bus for everything else, and is special so it doesn't need
	 * to be gated for rate changes.  It is also known as "clk_audio"
	 * in various hardware documentation.
	 */
	[BCM2835_CLOCK_VPU]	= REGISTER_VPU_CLK(
		.name = "vpu",
		.ctl_reg = CM_VPUCTL,
		.div_reg = CM_VPUDIV,
		.int_bits = 12,
		.frac_bits = 8,
		.flags = CLK_IS_CRITICAL,
		.is_vpu_clock = true),

	/* clocks with per parent mux */
	[BCM2835_CLOCK_AVEO]	= REGISTER_PER_CLK(
		.name = "aveo",
		.ctl_reg = CM_AVEOCTL,
		.div_reg = CM_AVEODIV,
		.int_bits = 4,
		.frac_bits = 0),
	[BCM2835_CLOCK_CAM0]	= REGISTER_PER_CLK(
		.name = "cam0",
		.ctl_reg = CM_CAM0CTL,
		.div_reg = CM_CAM0DIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_CAM1]	= REGISTER_PER_CLK(
		.name = "cam1",
		.ctl_reg = CM_CAM1CTL,
		.div_reg = CM_CAM1DIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_DFT]	= REGISTER_PER_CLK(
		.name = "dft",
		.ctl_reg = CM_DFTCTL,
		.div_reg = CM_DFTDIV,
		.int_bits = 5,
		.frac_bits = 0),
	[BCM2835_CLOCK_DPI]	= REGISTER_PER_CLK(
		.name = "dpi",
		.ctl_reg = CM_DPICTL,
		.div_reg = CM_DPIDIV,
		.int_bits = 4,
		.frac_bits = 8),

	/* Arasan EMMC clock */
	[BCM2835_CLOCK_EMMC]	= REGISTER_PER_CLK(
		.name = "emmc",
		.ctl_reg = CM_EMMCCTL,
		.div_reg = CM_EMMCDIV,
		.int_bits = 4,
		.frac_bits = 8),

	/* General purpose (GPIO) clocks */
	[BCM2835_CLOCK_GP0]	= REGISTER_PER_CLK(
		.name = "gp0",
		.ctl_reg = CM_GP0CTL,
		.div_reg = CM_GP0DIV,
		.int_bits = 12,
		.frac_bits = 12,
		.is_mash_clock = true),
	[BCM2835_CLOCK_GP1]	= REGISTER_PER_CLK(
		.name = "gp1",
		.ctl_reg = CM_GP1CTL,
		.div_reg = CM_GP1DIV,
		.int_bits = 12,
		.frac_bits = 12,
		.flags = CLK_IS_CRITICAL,
		.is_mash_clock = true),
	[BCM2835_CLOCK_GP2]	= REGISTER_PER_CLK(
		.name = "gp2",
		.ctl_reg = CM_GP2CTL,
		.div_reg = CM_GP2DIV,
		.int_bits = 12,
		.frac_bits = 12,
		.flags = CLK_IS_CRITICAL),

	/* HDMI state machine */
	[BCM2835_CLOCK_HSM]	= REGISTER_PER_CLK(
		.name = "hsm",
		.ctl_reg = CM_HSMCTL,
		.div_reg = CM_HSMDIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_PCM]	= REGISTER_PER_CLK(
		.name = "pcm",
		.ctl_reg = CM_PCMCTL,
		.div_reg = CM_PCMDIV,
		.int_bits = 12,
		.frac_bits = 12,
		.is_mash_clock = true),
	[BCM2835_CLOCK_PWM]	= REGISTER_PER_CLK(
		.name = "pwm",
		.ctl_reg = CM_PWMCTL,
		.div_reg = CM_PWMDIV,
		.int_bits = 12,
		.frac_bits = 12,
		.is_mash_clock = true),
	[BCM2835_CLOCK_SLIM]	= REGISTER_PER_CLK(
		.name = "slim",
		.ctl_reg = CM_SLIMCTL,
		.div_reg = CM_SLIMDIV,
		.int_bits = 12,
		.frac_bits = 12,
		.is_mash_clock = true),
	[BCM2835_CLOCK_SMI]	= REGISTER_PER_CLK(
		.name = "smi",
		.ctl_reg = CM_SMICTL,
		.div_reg = CM_SMIDIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_UART]	= REGISTER_PER_CLK(
		.name = "uart",
		.ctl_reg = CM_UARTCTL,
		.div_reg = CM_UARTDIV,
		.int_bits = 10,
		.frac_bits = 12),

	/* TV encoder clock.  Only operating frequency is 108Mhz.  */
	[BCM2835_CLOCK_VEC]	= REGISTER_PER_CLK(
		.name = "vec",
		.ctl_reg = CM_VECCTL,
		.div_reg = CM_VECDIV,
		.int_bits = 4,
		.frac_bits = 0,
		/*
		 * Allow rate change propagation only on PLLH_AUX which is
		 * assigned index 7 in the parent array.
		 */
		.set_rate_parent = BIT(7)),

	/* dsi clocks */
	[BCM2835_CLOCK_DSI0E]	= REGISTER_PER_CLK(
		.name = "dsi0e",
		.ctl_reg = CM_DSI0ECTL,
		.div_reg = CM_DSI0EDIV,
		.int_bits = 4,
		.frac_bits = 8),
	[BCM2835_CLOCK_DSI1E]	= REGISTER_PER_CLK(
		.name = "dsi1e",
		.ctl_reg = CM_DSI1ECTL,
		.div_reg = CM_DSI1EDIV,
		.int_bits = 4,
		.frac_bits = 8),

	/* the gates */

	/*
	 * CM_PERIICTL (and CM_PERIACTL, CM_SYSCTL and CM_VPUCTL if
	 * you have the debug bit set in the power manager, which we
	 * don't bother exposing) are individual gates off of the
	 * non-stop vpu clock.
	 */
	[BCM2835_CLOCK_PERI_IMAGE] = REGISTER_GATE(
		.name = "peri_image",
		.parent = "vpu",
		.ctl_reg = CM_PERIICTL),
};

static bool bcm2835_clk_claimed[ARRAY_SIZE(clk_desc_array)];

/*
 * Permanently take a reference on the parent of the SDRAM clock.
 *
 * While the SDRAM is being driven by its dedicated PLL most of the
 * time, there is a little loop running in the firmware that
 * periodically switches the SDRAM to using our CM clock to do PVT
 * recalibration, with the assumption that the previously configured
 * SDRAM parent is still enabled and running.
 */
static int bcm2835_mark_sdc_parent_critical(struct clk *sdc)
{
	struct clk *parent = clk_get_parent(sdc);

	if (IS_ERR(parent))
		return PTR_ERR(parent);

	return clk_prepare_enable(parent);
}

static bool bcm2835_clk_is_claimed(const char *name)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(clk_desc_array); i++) {
		const char *clk_name = *(const char **)(clk_desc_array[i].data);
		if (!strcmp(name, clk_name))
		    return bcm2835_clk_claimed[i];
	}

	return false;
}

static int bcm2835_clk_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct clk_hw **hws;
	struct bcm2835_cprman *cprman;
	struct resource *res;
	const struct bcm2835_clk_desc *desc;
	const size_t asize = ARRAY_SIZE(clk_desc_array);
	struct device_node *fw_node;
	size_t i;
	u32 clk_id;
	int ret;

	cprman = devm_kzalloc(dev, sizeof(*cprman) +
			      sizeof(*cprman->onecell.hws) * asize,
			      GFP_KERNEL);
	if (!cprman)
		return -ENOMEM;

	spin_lock_init(&cprman->regs_lock);
	cprman->dev = dev;
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	cprman->regs = devm_ioremap_resource(dev, res);
	if (IS_ERR(cprman->regs))
		return PTR_ERR(cprman->regs);

	fw_node = of_parse_phandle(dev->of_node, "firmware", 0);
	if (fw_node) {
		struct rpi_firmware *fw = rpi_firmware_get(NULL);
		if (!fw)
			return -EPROBE_DEFER;
		cprman->fw = fw;
	}

	memset(bcm2835_clk_claimed, 0, sizeof(bcm2835_clk_claimed));
	for (i = 0;
	     !of_property_read_u32_index(pdev->dev.of_node, "claim-clocks",
					 i, &clk_id);
	     i++)
		bcm2835_clk_claimed[clk_id]= true;

	cprman->osc_name = of_clk_get_parent_name(dev->of_node, 0);
	if (!cprman->osc_name)
		return -ENODEV;

	platform_set_drvdata(pdev, cprman);

	cprman->onecell.num = asize;
	hws = cprman->onecell.hws;

	for (i = 0; i < asize; i++) {
		desc = &clk_desc_array[i];
		if (desc->clk_register && desc->data)
			hws[i] = desc->clk_register(cprman, desc->data);
	}

	ret = bcm2835_mark_sdc_parent_critical(hws[BCM2835_CLOCK_SDRAM]->clk);
	if (ret)
		return ret;

	ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
				      &cprman->onecell);
	if (ret)
		return ret;

	/* note that we have registered all the clocks */
	dev_dbg(dev, "registered %d clocks\n", asize);

	return 0;
}

static const struct of_device_id bcm2835_clk_of_match[] = {
	{ .compatible = "brcm,bcm2835-cprman", },
	{}
};
MODULE_DEVICE_TABLE(of, bcm2835_clk_of_match);

static struct platform_driver bcm2835_clk_driver = {
	.driver = {
		.name = "bcm2835-clk",
		.of_match_table = bcm2835_clk_of_match,
	},
	.probe          = bcm2835_clk_probe,
};

static int __init __bcm2835_clk_driver_init(void)
{
	return platform_driver_register(&bcm2835_clk_driver);
}
core_initcall(__bcm2835_clk_driver_init);

MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
MODULE_DESCRIPTION("BCM2835 clock driver");
MODULE_LICENSE("GPL v2");