xref: /linux/drivers/clk/imx/clk-pllv2.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 #include <linux/kernel.h>
2 #include <linux/clk.h>
3 #include <linux/io.h>
4 #include <linux/errno.h>
5 #include <linux/delay.h>
6 #include <linux/slab.h>
7 #include <linux/err.h>
8 
9 #include <asm/div64.h>
10 
11 #include "clk.h"
12 
13 #define to_clk_pllv2(clk) (container_of(clk, struct clk_pllv2, clk))
14 
15 /* PLL Register Offsets */
16 #define MXC_PLL_DP_CTL			0x00
17 #define MXC_PLL_DP_CONFIG		0x04
18 #define MXC_PLL_DP_OP			0x08
19 #define MXC_PLL_DP_MFD			0x0C
20 #define MXC_PLL_DP_MFN			0x10
21 #define MXC_PLL_DP_MFNMINUS		0x14
22 #define MXC_PLL_DP_MFNPLUS		0x18
23 #define MXC_PLL_DP_HFS_OP		0x1C
24 #define MXC_PLL_DP_HFS_MFD		0x20
25 #define MXC_PLL_DP_HFS_MFN		0x24
26 #define MXC_PLL_DP_MFN_TOGC		0x28
27 #define MXC_PLL_DP_DESTAT		0x2c
28 
29 /* PLL Register Bit definitions */
30 #define MXC_PLL_DP_CTL_MUL_CTRL		0x2000
31 #define MXC_PLL_DP_CTL_DPDCK0_2_EN	0x1000
32 #define MXC_PLL_DP_CTL_DPDCK0_2_OFFSET	12
33 #define MXC_PLL_DP_CTL_ADE		0x800
34 #define MXC_PLL_DP_CTL_REF_CLK_DIV	0x400
35 #define MXC_PLL_DP_CTL_REF_CLK_SEL_MASK	(3 << 8)
36 #define MXC_PLL_DP_CTL_REF_CLK_SEL_OFFSET	8
37 #define MXC_PLL_DP_CTL_HFSM		0x80
38 #define MXC_PLL_DP_CTL_PRE		0x40
39 #define MXC_PLL_DP_CTL_UPEN		0x20
40 #define MXC_PLL_DP_CTL_RST		0x10
41 #define MXC_PLL_DP_CTL_RCP		0x8
42 #define MXC_PLL_DP_CTL_PLM		0x4
43 #define MXC_PLL_DP_CTL_BRM0		0x2
44 #define MXC_PLL_DP_CTL_LRF		0x1
45 
46 #define MXC_PLL_DP_CONFIG_BIST		0x8
47 #define MXC_PLL_DP_CONFIG_SJC_CE	0x4
48 #define MXC_PLL_DP_CONFIG_AREN		0x2
49 #define MXC_PLL_DP_CONFIG_LDREQ		0x1
50 
51 #define MXC_PLL_DP_OP_MFI_OFFSET	4
52 #define MXC_PLL_DP_OP_MFI_MASK		(0xF << 4)
53 #define MXC_PLL_DP_OP_PDF_OFFSET	0
54 #define MXC_PLL_DP_OP_PDF_MASK		0xF
55 
56 #define MXC_PLL_DP_MFD_OFFSET		0
57 #define MXC_PLL_DP_MFD_MASK		0x07FFFFFF
58 
59 #define MXC_PLL_DP_MFN_OFFSET		0x0
60 #define MXC_PLL_DP_MFN_MASK		0x07FFFFFF
61 
62 #define MXC_PLL_DP_MFN_TOGC_TOG_DIS	(1 << 17)
63 #define MXC_PLL_DP_MFN_TOGC_TOG_EN	(1 << 16)
64 #define MXC_PLL_DP_MFN_TOGC_CNT_OFFSET	0x0
65 #define MXC_PLL_DP_MFN_TOGC_CNT_MASK	0xFFFF
66 
67 #define MXC_PLL_DP_DESTAT_TOG_SEL	(1 << 31)
68 #define MXC_PLL_DP_DESTAT_MFN		0x07FFFFFF
69 
70 #define MAX_DPLL_WAIT_TRIES	1000 /* 1000 * udelay(1) = 1ms */
71 
72 struct clk_pllv2 {
73 	struct clk_hw	hw;
74 	void __iomem	*base;
75 };
76 
77 static unsigned long __clk_pllv2_recalc_rate(unsigned long parent_rate,
78 		u32 dp_ctl, u32 dp_op, u32 dp_mfd, u32 dp_mfn)
79 {
80 	long mfi, mfn, mfd, pdf, ref_clk, mfn_abs;
81 	unsigned long dbl;
82 	s64 temp;
83 
84 	dbl = dp_ctl & MXC_PLL_DP_CTL_DPDCK0_2_EN;
85 
86 	pdf = dp_op & MXC_PLL_DP_OP_PDF_MASK;
87 	mfi = (dp_op & MXC_PLL_DP_OP_MFI_MASK) >> MXC_PLL_DP_OP_MFI_OFFSET;
88 	mfi = (mfi <= 5) ? 5 : mfi;
89 	mfd = dp_mfd & MXC_PLL_DP_MFD_MASK;
90 	mfn = mfn_abs = dp_mfn & MXC_PLL_DP_MFN_MASK;
91 	/* Sign extend to 32-bits */
92 	if (mfn >= 0x04000000) {
93 		mfn |= 0xFC000000;
94 		mfn_abs = -mfn;
95 	}
96 
97 	ref_clk = 2 * parent_rate;
98 	if (dbl != 0)
99 		ref_clk *= 2;
100 
101 	ref_clk /= (pdf + 1);
102 	temp = (u64) ref_clk * mfn_abs;
103 	do_div(temp, mfd + 1);
104 	if (mfn < 0)
105 		temp = -temp;
106 	temp = (ref_clk * mfi) + temp;
107 
108 	return temp;
109 }
110 
111 static unsigned long clk_pllv2_recalc_rate(struct clk_hw *hw,
112 		unsigned long parent_rate)
113 {
114 	u32 dp_op, dp_mfd, dp_mfn, dp_ctl;
115 	void __iomem *pllbase;
116 	struct clk_pllv2 *pll = to_clk_pllv2(hw);
117 
118 	pllbase = pll->base;
119 
120 	dp_ctl = __raw_readl(pllbase + MXC_PLL_DP_CTL);
121 	dp_op = __raw_readl(pllbase + MXC_PLL_DP_OP);
122 	dp_mfd = __raw_readl(pllbase + MXC_PLL_DP_MFD);
123 	dp_mfn = __raw_readl(pllbase + MXC_PLL_DP_MFN);
124 
125 	return __clk_pllv2_recalc_rate(parent_rate, dp_ctl, dp_op, dp_mfd, dp_mfn);
126 }
127 
128 static int __clk_pllv2_set_rate(unsigned long rate, unsigned long parent_rate,
129 		u32 *dp_op, u32 *dp_mfd, u32 *dp_mfn)
130 {
131 	u32 reg;
132 	long mfi, pdf, mfn, mfd = 999999;
133 	s64 temp64;
134 	unsigned long quad_parent_rate;
135 
136 	quad_parent_rate = 4 * parent_rate;
137 	pdf = mfi = -1;
138 	while (++pdf < 16 && mfi < 5)
139 		mfi = rate * (pdf+1) / quad_parent_rate;
140 	if (mfi > 15)
141 		return -EINVAL;
142 	pdf--;
143 
144 	temp64 = rate * (pdf + 1) - quad_parent_rate * mfi;
145 	do_div(temp64, quad_parent_rate / 1000000);
146 	mfn = (long)temp64;
147 
148 	reg = mfi << 4 | pdf;
149 
150 	*dp_op = reg;
151 	*dp_mfd = mfd;
152 	*dp_mfn = mfn;
153 
154 	return 0;
155 }
156 
157 static int clk_pllv2_set_rate(struct clk_hw *hw, unsigned long rate,
158 		unsigned long parent_rate)
159 {
160 	struct clk_pllv2 *pll = to_clk_pllv2(hw);
161 	void __iomem *pllbase;
162 	u32 dp_ctl, dp_op, dp_mfd, dp_mfn;
163 	int ret;
164 
165 	pllbase = pll->base;
166 
167 
168 	ret = __clk_pllv2_set_rate(rate, parent_rate, &dp_op, &dp_mfd, &dp_mfn);
169 	if (ret)
170 		return ret;
171 
172 	dp_ctl = __raw_readl(pllbase + MXC_PLL_DP_CTL);
173 	/* use dpdck0_2 */
174 	__raw_writel(dp_ctl | 0x1000L, pllbase + MXC_PLL_DP_CTL);
175 
176 	__raw_writel(dp_op, pllbase + MXC_PLL_DP_OP);
177 	__raw_writel(dp_mfd, pllbase + MXC_PLL_DP_MFD);
178 	__raw_writel(dp_mfn, pllbase + MXC_PLL_DP_MFN);
179 
180 	return 0;
181 }
182 
183 static long clk_pllv2_round_rate(struct clk_hw *hw, unsigned long rate,
184 		unsigned long *prate)
185 {
186 	u32 dp_op, dp_mfd, dp_mfn;
187 
188 	__clk_pllv2_set_rate(rate, *prate, &dp_op, &dp_mfd, &dp_mfn);
189 	return __clk_pllv2_recalc_rate(*prate, MXC_PLL_DP_CTL_DPDCK0_2_EN,
190 			dp_op, dp_mfd, dp_mfn);
191 }
192 
193 static int clk_pllv2_prepare(struct clk_hw *hw)
194 {
195 	struct clk_pllv2 *pll = to_clk_pllv2(hw);
196 	u32 reg;
197 	void __iomem *pllbase;
198 	int i = 0;
199 
200 	pllbase = pll->base;
201 	reg = __raw_readl(pllbase + MXC_PLL_DP_CTL) | MXC_PLL_DP_CTL_UPEN;
202 	__raw_writel(reg, pllbase + MXC_PLL_DP_CTL);
203 
204 	/* Wait for lock */
205 	do {
206 		reg = __raw_readl(pllbase + MXC_PLL_DP_CTL);
207 		if (reg & MXC_PLL_DP_CTL_LRF)
208 			break;
209 
210 		udelay(1);
211 	} while (++i < MAX_DPLL_WAIT_TRIES);
212 
213 	if (i == MAX_DPLL_WAIT_TRIES) {
214 		pr_err("MX5: pll locking failed\n");
215 		return -EINVAL;
216 	}
217 
218 	return 0;
219 }
220 
221 static void clk_pllv2_unprepare(struct clk_hw *hw)
222 {
223 	struct clk_pllv2 *pll = to_clk_pllv2(hw);
224 	u32 reg;
225 	void __iomem *pllbase;
226 
227 	pllbase = pll->base;
228 	reg = __raw_readl(pllbase + MXC_PLL_DP_CTL) & ~MXC_PLL_DP_CTL_UPEN;
229 	__raw_writel(reg, pllbase + MXC_PLL_DP_CTL);
230 }
231 
232 static struct clk_ops clk_pllv2_ops = {
233 	.prepare = clk_pllv2_prepare,
234 	.unprepare = clk_pllv2_unprepare,
235 	.recalc_rate = clk_pllv2_recalc_rate,
236 	.round_rate = clk_pllv2_round_rate,
237 	.set_rate = clk_pllv2_set_rate,
238 };
239 
240 struct clk *imx_clk_pllv2(const char *name, const char *parent,
241 		void __iomem *base)
242 {
243 	struct clk_pllv2 *pll;
244 	struct clk *clk;
245 	struct clk_init_data init;
246 
247 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
248 	if (!pll)
249 		return ERR_PTR(-ENOMEM);
250 
251 	pll->base = base;
252 
253 	init.name = name;
254 	init.ops = &clk_pllv2_ops;
255 	init.flags = 0;
256 	init.parent_names = &parent;
257 	init.num_parents = 1;
258 
259 	pll->hw.init = &init;
260 
261 	clk = clk_register(NULL, &pll->hw);
262 	if (IS_ERR(clk))
263 		kfree(pll);
264 
265 	return clk;
266 }
267