[mirror_ubuntu-artful-kernel.git] / drivers / clk / clk-gemini.c

/*
 * Cortina Gemini SoC Clock Controller driver
 * Copyright (c) 2017 Linus Walleij <linus.walleij@linaro.org>
 */

#define pr_fmt(fmt) "clk-gemini: " fmt

#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/clk-provider.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
#include <linux/reset-controller.h>
#include <dt-bindings/reset/cortina,gemini-reset.h>
#include <dt-bindings/clock/cortina,gemini-clock.h>

/* Globally visible clocks */
static DEFINE_SPINLOCK(gemini_clk_lock);

#define GEMINI_GLOBAL_STATUS		0x04
#define PLL_OSC_SEL			BIT(30)
#define AHBSPEED_SHIFT			(15)
#define AHBSPEED_MASK			0x07
#define CPU_AHB_RATIO_SHIFT		(18)
#define CPU_AHB_RATIO_MASK		0x03

#define GEMINI_GLOBAL_PLL_CONTROL	0x08

#define GEMINI_GLOBAL_SOFT_RESET	0x0c

#define GEMINI_GLOBAL_MISC_CONTROL	0x30
#define PCI_CLK_66MHZ			BIT(18)
#define PCI_CLK_OE			BIT(17)

#define GEMINI_GLOBAL_CLOCK_CONTROL	0x34
#define PCI_CLKRUN_EN			BIT(16)
#define TVC_HALFDIV_SHIFT		(24)
#define TVC_HALFDIV_MASK		0x1f
#define SECURITY_CLK_SEL		BIT(29)

#define GEMINI_GLOBAL_PCI_DLL_CONTROL	0x44
#define PCI_DLL_BYPASS			BIT(31)
#define PCI_DLL_TAP_SEL_MASK		0x1f

/**
 * struct gemini_data_data - Gemini gated clocks
 * @bit_idx: the bit used to gate this clock in the clock register
 * @name: the clock name
 * @parent_name: the name of the parent clock
 * @flags: standard clock framework flags
 */
struct gemini_gate_data {
	u8 bit_idx;
	const char *name;
	const char *parent_name;
	unsigned long flags;
};

/**
 * struct clk_gemini_pci - Gemini PCI clock
 * @hw: corresponding clock hardware entry
 * @map: regmap to access the registers
 * @rate: current rate
 */
struct clk_gemini_pci {
	struct clk_hw hw;
	struct regmap *map;
	unsigned long rate;
};

/**
 * struct gemini_reset - gemini reset controller
 * @map: regmap to access the containing system controller
 * @rcdev: reset controller device
 */
struct gemini_reset {
	struct regmap *map;
	struct reset_controller_dev rcdev;
};

/* Keeps track of all clocks */
static struct clk_hw_onecell_data *gemini_clk_data;

static const struct gemini_gate_data gemini_gates[] = {
	{ 1, "security-gate", "secdiv", 0 },
	{ 2, "gmac0-gate", "ahb", 0 },
	{ 3, "gmac1-gate", "ahb", 0 },
	{ 4, "sata0-gate", "ahb", 0 },
	{ 5, "sata1-gate", "ahb", 0 },
	{ 6, "usb0-gate", "ahb", 0 },
	{ 7, "usb1-gate", "ahb", 0 },
	{ 8, "ide-gate", "ahb", 0 },
	{ 9, "pci-gate", "ahb", 0 },
	/*
	 * The DDR controller may never have a driver, but certainly must
	 * not be gated off.
	 */
	{ 10, "ddr-gate", "ahb", CLK_IS_CRITICAL },
	/*
	 * The flash controller must be on to access NOR flash through the
	 * memory map.
	 */
	{ 11, "flash-gate", "ahb", CLK_IGNORE_UNUSED },
	{ 12, "tvc-gate", "ahb", 0 },
	{ 13, "boot-gate", "apb", 0 },
};

#define to_pciclk(_hw) container_of(_hw, struct clk_gemini_pci, hw)

#define to_gemini_reset(p) container_of((p), struct gemini_reset, rcdev)

static unsigned long gemini_pci_recalc_rate(struct clk_hw *hw,
					    unsigned long parent_rate)
{
	struct clk_gemini_pci *pciclk = to_pciclk(hw);
	u32 val;

	regmap_read(pciclk->map, GEMINI_GLOBAL_MISC_CONTROL, &val);
	if (val & PCI_CLK_66MHZ)
		return 66000000;
	return 33000000;
}

static long gemini_pci_round_rate(struct clk_hw *hw, unsigned long rate,
				  unsigned long *prate)
{
	/* We support 33 and 66 MHz */
	if (rate < 48000000)
		return 33000000;
	return 66000000;
}

static int gemini_pci_set_rate(struct clk_hw *hw, unsigned long rate,
			       unsigned long parent_rate)
{
	struct clk_gemini_pci *pciclk = to_pciclk(hw);

	if (rate == 33000000)
		return regmap_update_bits(pciclk->map,
					  GEMINI_GLOBAL_MISC_CONTROL,
					  PCI_CLK_66MHZ, 0);
	if (rate == 66000000)
		return regmap_update_bits(pciclk->map,
					  GEMINI_GLOBAL_MISC_CONTROL,
					  0, PCI_CLK_66MHZ);
	return -EINVAL;
}

static int gemini_pci_enable(struct clk_hw *hw)
{
	struct clk_gemini_pci *pciclk = to_pciclk(hw);

	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
			   0, PCI_CLKRUN_EN);
	regmap_update_bits(pciclk->map,
			   GEMINI_GLOBAL_MISC_CONTROL,
			   0, PCI_CLK_OE);
	return 0;
}

static void gemini_pci_disable(struct clk_hw *hw)
{
	struct clk_gemini_pci *pciclk = to_pciclk(hw);

	regmap_update_bits(pciclk->map,
			   GEMINI_GLOBAL_MISC_CONTROL,
			   PCI_CLK_OE, 0);
	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
			   PCI_CLKRUN_EN, 0);
}

static int gemini_pci_is_enabled(struct clk_hw *hw)
{
	struct clk_gemini_pci *pciclk = to_pciclk(hw);
	unsigned int val;

	regmap_read(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
	return !!(val & PCI_CLKRUN_EN);
}

static const struct clk_ops gemini_pci_clk_ops = {
	.recalc_rate = gemini_pci_recalc_rate,
	.round_rate = gemini_pci_round_rate,
	.set_rate = gemini_pci_set_rate,
	.enable = gemini_pci_enable,
	.disable = gemini_pci_disable,
	.is_enabled = gemini_pci_is_enabled,
};

static struct clk_hw *gemini_pci_clk_setup(const char *name,
					   const char *parent_name,
					   struct regmap *map)
{
	struct clk_gemini_pci *pciclk;
	struct clk_init_data init;
	int ret;

	pciclk = kzalloc(sizeof(*pciclk), GFP_KERNEL);
	if (!pciclk)
		return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &gemini_pci_clk_ops;
	init.flags = 0;
	init.parent_names = &parent_name;
	init.num_parents = 1;
	pciclk->map = map;
	pciclk->hw.init = &init;

	ret = clk_hw_register(NULL, &pciclk->hw);
	if (ret) {
		kfree(pciclk);
		return ERR_PTR(ret);
	}

	return &pciclk->hw;
}

/*
 * This is a self-deasserting reset controller.
 */
static int gemini_reset(struct reset_controller_dev *rcdev,
			unsigned long id)
{
	struct gemini_reset *gr = to_gemini_reset(rcdev);

	/* Manual says to always set BIT 30 (CPU1) to 1 */
	return regmap_write(gr->map,
			    GEMINI_GLOBAL_SOFT_RESET,
			    BIT(GEMINI_RESET_CPU1) | BIT(id));
}

static int gemini_reset_status(struct reset_controller_dev *rcdev,
			     unsigned long id)
{
	struct gemini_reset *gr = to_gemini_reset(rcdev);
	u32 val;
	int ret;

	ret = regmap_read(gr->map, GEMINI_GLOBAL_SOFT_RESET, &val);
	if (ret)
		return ret;

	return !!(val & BIT(id));
}

static const struct reset_control_ops gemini_reset_ops = {
	.reset = gemini_reset,
	.status = gemini_reset_status,
};

static int gemini_clk_probe(struct platform_device *pdev)
{
	/* Gives the fracions 1x, 1.5x, 1.85x and 2x */
	unsigned int cpu_ahb_mult[4] = { 1, 3, 24, 2 };
	unsigned int cpu_ahb_div[4] = { 1, 2, 13, 1 };
	void __iomem *base;
	struct gemini_reset *gr;
	struct regmap *map;
	struct clk_hw *hw;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	unsigned int mult, div;
	struct resource *res;
	u32 val;
	int ret;
	int i;

	gr = devm_kzalloc(dev, sizeof(*gr), GFP_KERNEL);
	if (!gr)
		return -ENOMEM;

	/* Remap the system controller for the exclusive register */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

	map = syscon_node_to_regmap(np);
	if (IS_ERR(map)) {
		dev_err(dev, "no syscon regmap\n");
		return PTR_ERR(map);
	}

	gr->map = map;
	gr->rcdev.owner = THIS_MODULE;
	gr->rcdev.nr_resets = 32;
	gr->rcdev.ops = &gemini_reset_ops;
	gr->rcdev.of_node = np;

	ret = devm_reset_controller_register(dev, &gr->rcdev);
	if (ret) {
		dev_err(dev, "could not register reset controller\n");
		return ret;
	}

	/* RTC clock 32768 Hz */
	hw = clk_hw_register_fixed_rate(NULL, "rtc", NULL, 0, 32768);
	gemini_clk_data->hws[GEMINI_CLK_RTC] = hw;

	/* CPU clock derived as a fixed ratio from the AHB clock */
	val >>= CPU_AHB_RATIO_SHIFT;
	val &= CPU_AHB_RATIO_MASK;
	hw = clk_hw_register_fixed_factor(NULL, "cpu", "ahb", 0,
					  cpu_ahb_mult[val],
					  cpu_ahb_div[val]);
	gemini_clk_data->hws[GEMINI_CLK_CPU] = hw;

	/* Security clock is 1:1 or 0.75 of APB */
	regmap_read(map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
	if (val & SECURITY_CLK_SEL) {
		mult = 1;
		div = 1;
	} else {
		mult = 3;
		div = 4;
	}
	hw = clk_hw_register_fixed_factor(NULL, "secdiv", "ahb", 0, mult, div);

	/*
	 * These are the leaf gates, at boot no clocks are gated.
	 */
	for (i = 0; i < ARRAY_SIZE(gemini_gates); i++) {
		const struct gemini_gate_data *gd;

		gd = &gemini_gates[i];
		gemini_clk_data->hws[GEMINI_CLK_GATES + i] =
			clk_hw_register_gate(NULL, gd->name,
					     gd->parent_name,
					     gd->flags,
					     base + GEMINI_GLOBAL_CLOCK_CONTROL,
					     gd->bit_idx,
					     CLK_GATE_SET_TO_DISABLE,
					     &gemini_clk_lock);
	}

	/*
	 * The TV Interface Controller has a 5-bit half divider register.
	 * This clock is supposed to be 27MHz as this is an exact multiple
	 * of PAL and NTSC frequencies. The register is undocumented :(
	 * FIXME: figure out the parent and how the divider works.
	 */
	mult = 1;
	div = ((val >> TVC_HALFDIV_SHIFT) & TVC_HALFDIV_MASK);
	dev_dbg(dev, "TVC half divider value = %d\n", div);
	div += 1;
	hw = clk_hw_register_fixed_rate(NULL, "tvcdiv", "xtal", 0, 27000000);
	gemini_clk_data->hws[GEMINI_CLK_TVC] = hw;

	/* FIXME: very unclear what the parent is */
	hw = gemini_pci_clk_setup("PCI", "xtal", map);
	gemini_clk_data->hws[GEMINI_CLK_PCI] = hw;

	/* FIXME: very unclear what the parent is */
	hw = clk_hw_register_fixed_rate(NULL, "uart", "xtal", 0, 48000000);
	gemini_clk_data->hws[GEMINI_CLK_UART] = hw;

	return 0;
}

static const struct of_device_id gemini_clk_dt_ids[] = {
	{ .compatible = "cortina,gemini-syscon", },
	{ /* sentinel */ },
};

static struct platform_driver gemini_clk_driver = {
	.probe  = gemini_clk_probe,
	.driver = {
		.name = "gemini-clk",
		.of_match_table = gemini_clk_dt_ids,
		.suppress_bind_attrs = true,
	},
};
builtin_platform_driver(gemini_clk_driver);

static void __init gemini_cc_init(struct device_node *np)
{
	struct regmap *map;
	struct clk_hw *hw;
	unsigned long freq;
	unsigned int mult, div;
	u32 val;
	int ret;
	int i;

	gemini_clk_data = kzalloc(sizeof(*gemini_clk_data) +
			sizeof(*gemini_clk_data->hws) * GEMINI_NUM_CLKS,
			GFP_KERNEL);
	if (!gemini_clk_data)
		return;

	/*
	 * This way all clock fetched before the platform device probes,
	 * except those we assign here for early use, will be deferred.
	 */
	for (i = 0; i < GEMINI_NUM_CLKS; i++)
		gemini_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);

	map = syscon_node_to_regmap(np);
	if (IS_ERR(map)) {
		pr_err("no syscon regmap\n");
		return;
	}
	/*
	 * We check that the regmap works on this very first access,
	 * but as this is an MMIO-backed regmap, subsequent regmap
	 * access is not going to fail and we skip error checks from
	 * this point.
	 */
	ret = regmap_read(map, GEMINI_GLOBAL_STATUS, &val);
	if (ret) {
		pr_err("failed to read global status register\n");
		return;
	}

	/*
	 * XTAL is the crystal oscillator, 60 or 30 MHz selected from
	 * strap pin E6
	 */
	if (val & PLL_OSC_SEL)
		freq = 30000000;
	else
		freq = 60000000;
	hw = clk_hw_register_fixed_rate(NULL, "xtal", NULL, 0, freq);
	pr_debug("main crystal @%lu MHz\n", freq / 1000000);

	/* VCO clock derived from the crystal */
	mult = 13 + ((val >> AHBSPEED_SHIFT) & AHBSPEED_MASK);
	div = 2;
	/* If we run on 30 MHz crystal we have to multiply with two */
	if (val & PLL_OSC_SEL)
		mult *= 2;
	hw = clk_hw_register_fixed_factor(NULL, "vco", "xtal", 0, mult, div);

	/* The AHB clock is always 1/3 of the VCO */
	hw = clk_hw_register_fixed_factor(NULL, "ahb", "vco", 0, 1, 3);
	gemini_clk_data->hws[GEMINI_CLK_AHB] = hw;

	/* The APB clock is always 1/6 of the AHB */
	hw = clk_hw_register_fixed_factor(NULL, "apb", "ahb", 0, 1, 6);
	gemini_clk_data->hws[GEMINI_CLK_APB] = hw;

	/* Register the clocks to be accessed by the device tree */
	gemini_clk_data->num = GEMINI_NUM_CLKS;
	of_clk_add_hw_provider(np, of_clk_hw_onecell_get, gemini_clk_data);
}
CLK_OF_DECLARE_DRIVER(gemini_cc, "cortina,gemini-syscon", gemini_cc_init);
Commit	Line	Data
846423f9 LW	1	/*
	2	* Cortina Gemini SoC Clock Controller driver
	3	* Copyright (c) 2017 Linus Walleij <linus.walleij@linaro.org>
	4	*/
	5
	6	#define pr_fmt(fmt) "clk-gemini: " fmt
	7
	8	#include <linux/init.h>
	9	#include <linux/module.h>
	10	#include <linux/platform_device.h>
	11	#include <linux/slab.h>
	12	#include <linux/err.h>
	13	#include <linux/io.h>
	14	#include <linux/clk-provider.h>
	15	#include <linux/of.h>
	16	#include <linux/of_address.h>
	17	#include <linux/mfd/syscon.h>
	18	#include <linux/regmap.h>
	19	#include <linux/spinlock.h>
	20	#include <linux/reset-controller.h>
	21	#include <dt-bindings/reset/cortina,gemini-reset.h>
	22	#include <dt-bindings/clock/cortina,gemini-clock.h>
	23
	24	/* Globally visible clocks */
	25	static DEFINE_SPINLOCK(gemini_clk_lock);
	26
	27	#define GEMINI_GLOBAL_STATUS 0x04
	28	#define PLL_OSC_SEL BIT(30)
	29	#define AHBSPEED_SHIFT (15)
	30	#define AHBSPEED_MASK 0x07
	31	#define CPU_AHB_RATIO_SHIFT (18)
	32	#define CPU_AHB_RATIO_MASK 0x03
	33
	34	#define GEMINI_GLOBAL_PLL_CONTROL 0x08
	35
	36	#define GEMINI_GLOBAL_SOFT_RESET 0x0c
	37
	38	#define GEMINI_GLOBAL_MISC_CONTROL 0x30
	39	#define PCI_CLK_66MHZ BIT(18)
	40	#define PCI_CLK_OE BIT(17)
	41
	42	#define GEMINI_GLOBAL_CLOCK_CONTROL 0x34
	43	#define PCI_CLKRUN_EN BIT(16)
	44	#define TVC_HALFDIV_SHIFT (24)
	45	#define TVC_HALFDIV_MASK 0x1f
	46	#define SECURITY_CLK_SEL BIT(29)
	47
	48	#define GEMINI_GLOBAL_PCI_DLL_CONTROL 0x44
	49	#define PCI_DLL_BYPASS BIT(31)
	50	#define PCI_DLL_TAP_SEL_MASK 0x1f
	51
	52	/**
	53	* struct gemini_data_data - Gemini gated clocks
	54	* @bit_idx: the bit used to gate this clock in the clock register
	55	* @name: the clock name
	56	* @parent_name: the name of the parent clock
	57	* @flags: standard clock framework flags
	58	*/
	59	struct gemini_gate_data {
	60	u8 bit_idx;
	61	const char *name;
	62	const char *parent_name;
	63	unsigned long flags;
	64	};
65
66	/**
67	* struct clk_gemini_pci - Gemini PCI clock
68	* @hw: corresponding clock hardware entry
69	* @map: regmap to access the registers
70	* @rate: current rate
71	*/
72	struct clk_gemini_pci {
73	struct clk_hw hw;
74	struct regmap *map;
75	unsigned long rate;
76	};
77
78	/**
79	* struct gemini_reset - gemini reset controller
80	* @map: regmap to access the containing system controller
81	* @rcdev: reset controller device
82	*/
83	struct gemini_reset {
84	struct regmap *map;
85	struct reset_controller_dev rcdev;
86	};
87
88	/* Keeps track of all clocks */
89	static struct clk_hw_onecell_data *gemini_clk_data;
90
91	static const struct gemini_gate_data gemini_gates[] = {
92	{ 1, "security-gate", "secdiv", 0 },
93	{ 2, "gmac0-gate", "ahb", 0 },
94	{ 3, "gmac1-gate", "ahb", 0 },
95	{ 4, "sata0-gate", "ahb", 0 },
96	{ 5, "sata1-gate", "ahb", 0 },
97	{ 6, "usb0-gate", "ahb", 0 },
98	{ 7, "usb1-gate", "ahb", 0 },
99	{ 8, "ide-gate", "ahb", 0 },
100	{ 9, "pci-gate", "ahb", 0 },
101	/*
102	* The DDR controller may never have a driver, but certainly must
103	* not be gated off.
104	*/
105	{ 10, "ddr-gate", "ahb", CLK_IS_CRITICAL },
106	/*
107	* The flash controller must be on to access NOR flash through the
108	* memory map.
109	*/
110	{ 11, "flash-gate", "ahb", CLK_IGNORE_UNUSED },
111	{ 12, "tvc-gate", "ahb", 0 },
112	{ 13, "boot-gate", "apb", 0 },
113	};
114
115	#define to_pciclk(_hw) container_of(_hw, struct clk_gemini_pci, hw)
116
117	#define to_gemini_reset(p) container_of((p), struct gemini_reset, rcdev)
118
119	static unsigned long gemini_pci_recalc_rate(struct clk_hw *hw,
120	unsigned long parent_rate)
121	{
122	struct clk_gemini_pci *pciclk = to_pciclk(hw);
123	u32 val;
124
125	regmap_read(pciclk->map, GEMINI_GLOBAL_MISC_CONTROL, &val);
126	if (val & PCI_CLK_66MHZ)
127	return 66000000;
128	return 33000000;
129	}
130
131	static long gemini_pci_round_rate(struct clk_hw *hw, unsigned long rate,
132	unsigned long *prate)
133	{
134	/* We support 33 and 66 MHz */
135	if (rate < 48000000)
136	return 33000000;
137	return 66000000;
138	}
139
140	static int gemini_pci_set_rate(struct clk_hw *hw, unsigned long rate,
141	unsigned long parent_rate)
142	{
143	struct clk_gemini_pci *pciclk = to_pciclk(hw);
144
145	if (rate == 33000000)
146	return regmap_update_bits(pciclk->map,
147	GEMINI_GLOBAL_MISC_CONTROL,
148	PCI_CLK_66MHZ, 0);
149	if (rate == 66000000)
150	return regmap_update_bits(pciclk->map,
151	GEMINI_GLOBAL_MISC_CONTROL,
152	0, PCI_CLK_66MHZ);
153	return -EINVAL;
154	}
155
156	static int gemini_pci_enable(struct clk_hw *hw)
157	{
158	struct clk_gemini_pci *pciclk = to_pciclk(hw);
159
160	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
161	0, PCI_CLKRUN_EN);
162	regmap_update_bits(pciclk->map,
163	GEMINI_GLOBAL_MISC_CONTROL,
164	0, PCI_CLK_OE);
165	return 0;
166	}
167
168	static void gemini_pci_disable(struct clk_hw *hw)
169	{
170	struct clk_gemini_pci *pciclk = to_pciclk(hw);
171
172	regmap_update_bits(pciclk->map,
173	GEMINI_GLOBAL_MISC_CONTROL,
174	PCI_CLK_OE, 0);
175	regmap_update_bits(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL,
176	PCI_CLKRUN_EN, 0);
177	}
178
179	static int gemini_pci_is_enabled(struct clk_hw *hw)
180	{
181	struct clk_gemini_pci *pciclk = to_pciclk(hw);
182	unsigned int val;
183
184	regmap_read(pciclk->map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
185	return !!(val & PCI_CLKRUN_EN);
186	}
187
188	static const struct clk_ops gemini_pci_clk_ops = {
189	.recalc_rate = gemini_pci_recalc_rate,
190	.round_rate = gemini_pci_round_rate,
191	.set_rate = gemini_pci_set_rate,
192	.enable = gemini_pci_enable,
193	.disable = gemini_pci_disable,
194	.is_enabled = gemini_pci_is_enabled,
195	};
196
197	static struct clk_hw gemini_pci_clk_setup(const char name,
198	const char *parent_name,
199	struct regmap *map)
200	{
201	struct clk_gemini_pci *pciclk;
202	struct clk_init_data init;
203	int ret;
204
205	pciclk = kzalloc(sizeof(*pciclk), GFP_KERNEL);
206	if (!pciclk)
207	return ERR_PTR(-ENOMEM);
208
209	init.name = name;
210	init.ops = &gemini_pci_clk_ops;
211	init.flags = 0;
212	init.parent_names = &parent_name;
213	init.num_parents = 1;
214	pciclk->map = map;
215	pciclk->hw.init = &init;
216
217	ret = clk_hw_register(NULL, &pciclk->hw);
218	if (ret) {
219	kfree(pciclk);
220	return ERR_PTR(ret);
221	}
222
223	return &pciclk->hw;
224	}
225
226	/*
227	* This is a self-deasserting reset controller.
228	*/
229	static int gemini_reset(struct reset_controller_dev *rcdev,
230	unsigned long id)
231	{
232	struct gemini_reset *gr = to_gemini_reset(rcdev);
233
234	/* Manual says to always set BIT 30 (CPU1) to 1 */
235	return regmap_write(gr->map,
236	GEMINI_GLOBAL_SOFT_RESET,
237	BIT(GEMINI_RESET_CPU1) \| BIT(id));
238	}
239
240	static int gemini_reset_status(struct reset_controller_dev *rcdev,
241	unsigned long id)
242	{
243	struct gemini_reset *gr = to_gemini_reset(rcdev);
244	u32 val;
245	int ret;
246
247	ret = regmap_read(gr->map, GEMINI_GLOBAL_SOFT_RESET, &val);
248	if (ret)
249	return ret;
250
251	return !!(val & BIT(id));
252	}
253
254	static const struct reset_control_ops gemini_reset_ops = {
255	.reset = gemini_reset,
256	.status = gemini_reset_status,
257	};
258
259	static int gemini_clk_probe(struct platform_device *pdev)
260	{
261	/* Gives the fracions 1x, 1.5x, 1.85x and 2x */
262	unsigned int cpu_ahb_mult[4] = { 1, 3, 24, 2 };
263	unsigned int cpu_ahb_div[4] = { 1, 2, 13, 1 };
264	void __iomem *base;
265	struct gemini_reset *gr;
266	struct regmap *map;
267	struct clk_hw *hw;
268	struct device *dev = &pdev->dev;
269	struct device_node *np = dev->of_node;
270	unsigned int mult, div;
271	struct resource *res;
272	u32 val;
273	int ret;
274	int i;
275
276	gr = devm_kzalloc(dev, sizeof(*gr), GFP_KERNEL);
277	if (!gr)
278	return -ENOMEM;
279
280	/* Remap the system controller for the exclusive register */
281	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
282	base = devm_ioremap_resource(dev, res);
283	if (IS_ERR(base))
284	return PTR_ERR(base);
285
286	map = syscon_node_to_regmap(np);
287	if (IS_ERR(map)) {
288	dev_err(dev, "no syscon regmap\n");
289	return PTR_ERR(map);
290	}
291
292	gr->map = map;
293	gr->rcdev.owner = THIS_MODULE;
294	gr->rcdev.nr_resets = 32;
295	gr->rcdev.ops = &gemini_reset_ops;
296	gr->rcdev.of_node = np;
297
298	ret = devm_reset_controller_register(dev, &gr->rcdev);
299	if (ret) {
300	dev_err(dev, "could not register reset controller\n");
301	return ret;
302	}
303
304	/* RTC clock 32768 Hz */
305	hw = clk_hw_register_fixed_rate(NULL, "rtc", NULL, 0, 32768);
306	gemini_clk_data->hws[GEMINI_CLK_RTC] = hw;
307
308	/* CPU clock derived as a fixed ratio from the AHB clock */
309	val >>= CPU_AHB_RATIO_SHIFT;
310	val &= CPU_AHB_RATIO_MASK;
311	hw = clk_hw_register_fixed_factor(NULL, "cpu", "ahb", 0,
312	cpu_ahb_mult[val],
313	cpu_ahb_div[val]);
314	gemini_clk_data->hws[GEMINI_CLK_CPU] = hw;
315
316	/* Security clock is 1:1 or 0.75 of APB */
317	regmap_read(map, GEMINI_GLOBAL_CLOCK_CONTROL, &val);
318	if (val & SECURITY_CLK_SEL) {
319	mult = 1;
320	div = 1;
321	} else {
322	mult = 3;
323	div = 4;
324	}
325	hw = clk_hw_register_fixed_factor(NULL, "secdiv", "ahb", 0, mult, div);
326
327	/*
328	* These are the leaf gates, at boot no clocks are gated.
329	*/
330	for (i = 0; i < ARRAY_SIZE(gemini_gates); i++) {
331	const struct gemini_gate_data *gd;
332
333	gd = &gemini_gates[i];
334	gemini_clk_data->hws[GEMINI_CLK_GATES + i] =
335	clk_hw_register_gate(NULL, gd->name,
336	gd->parent_name,
337	gd->flags,
338	base + GEMINI_GLOBAL_CLOCK_CONTROL,
339	gd->bit_idx,
340	CLK_GATE_SET_TO_DISABLE,
341	&gemini_clk_lock);
342	}
343
344	/*
345	* The TV Interface Controller has a 5-bit half divider register.
346	* This clock is supposed to be 27MHz as this is an exact multiple
347	* of PAL and NTSC frequencies. The register is undocumented :(
348	* FIXME: figure out the parent and how the divider works.
349	*/
350	mult = 1;
351	div = ((val >> TVC_HALFDIV_SHIFT) & TVC_HALFDIV_MASK);
352	dev_dbg(dev, "TVC half divider value = %d\n", div);
353	div += 1;
354	hw = clk_hw_register_fixed_rate(NULL, "tvcdiv", "xtal", 0, 27000000);
355	gemini_clk_data->hws[GEMINI_CLK_TVC] = hw;
356
357	/* FIXME: very unclear what the parent is */
358	hw = gemini_pci_clk_setup("PCI", "xtal", map);
359	gemini_clk_data->hws[GEMINI_CLK_PCI] = hw;
360
361	/* FIXME: very unclear what the parent is */
362	hw = clk_hw_register_fixed_rate(NULL, "uart", "xtal", 0, 48000000);
363	gemini_clk_data->hws[GEMINI_CLK_UART] = hw;
364
365	return 0;
366	}
367
368	static const struct of_device_id gemini_clk_dt_ids[] = {
369	{ .compatible = "cortina,gemini-syscon", },
370	{ /* sentinel */ },
371	};
372
373	static struct platform_driver gemini_clk_driver = {
374	.probe = gemini_clk_probe,
375	.driver = {
376	.name = "gemini-clk",
377	.of_match_table = gemini_clk_dt_ids,
378	.suppress_bind_attrs = true,
379	},
380	};
381	builtin_platform_driver(gemini_clk_driver);
382
383	static void __init gemini_cc_init(struct device_node *np)
384	{
385	struct regmap *map;
386	struct clk_hw *hw;
387	unsigned long freq;
388	unsigned int mult, div;
389	u32 val;
390	int ret;
391	int i;
392
393	gemini_clk_data = kzalloc(sizeof(*gemini_clk_data) +
394	sizeof(gemini_clk_data->hws) GEMINI_NUM_CLKS,
395	GFP_KERNEL);
396	if (!gemini_clk_data)
397	return;
398
399	/*
400	* This way all clock fetched before the platform device probes,
401	* except those we assign here for early use, will be deferred.
402	*/
403	for (i = 0; i < GEMINI_NUM_CLKS; i++)
404	gemini_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
405
406	map = syscon_node_to_regmap(np);
407	if (IS_ERR(map)) {
408	pr_err("no syscon regmap\n");
409	return;
410	}
411	/*
412	* We check that the regmap works on this very first access,
413	* but as this is an MMIO-backed regmap, subsequent regmap
414	* access is not going to fail and we skip error checks from
415	* this point.
416	*/
417	ret = regmap_read(map, GEMINI_GLOBAL_STATUS, &val);
418	if (ret) {
419	pr_err("failed to read global status register\n");
420	return;
421	}
422
423	/*
424	* XTAL is the crystal oscillator, 60 or 30 MHz selected from
425	* strap pin E6
426	*/
427	if (val & PLL_OSC_SEL)
428	freq = 30000000;
429	else
430	freq = 60000000;
431	hw = clk_hw_register_fixed_rate(NULL, "xtal", NULL, 0, freq);
432	pr_debug("main crystal @%lu MHz\n", freq / 1000000);
433
434	/* VCO clock derived from the crystal */
435	mult = 13 + ((val >> AHBSPEED_SHIFT) & AHBSPEED_MASK);
436	div = 2;
437	/* If we run on 30 MHz crystal we have to multiply with two */
438	if (val & PLL_OSC_SEL)
439	mult *= 2;
440	hw = clk_hw_register_fixed_factor(NULL, "vco", "xtal", 0, mult, div);
441
442	/* The AHB clock is always 1/3 of the VCO */
443	hw = clk_hw_register_fixed_factor(NULL, "ahb", "vco", 0, 1, 3);
444	gemini_clk_data->hws[GEMINI_CLK_AHB] = hw;
445
446	/* The APB clock is always 1/6 of the AHB */
447	hw = clk_hw_register_fixed_factor(NULL, "apb", "ahb", 0, 1, 6);
448	gemini_clk_data->hws[GEMINI_CLK_APB] = hw;
449
450	/* Register the clocks to be accessed by the device tree */
451	gemini_clk_data->num = GEMINI_NUM_CLKS;
452	of_clk_add_hw_provider(np, of_clk_hw_onecell_get, gemini_clk_data);
453	}
454	CLK_OF_DECLARE_DRIVER(gemini_cc, "cortina,gemini-syscon", gemini_cc_init);