xref: /openbmc/u-boot/drivers/clk/clk_stm32h7.c (revision 9d466f2f)
1 /*
2  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
3  * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <clk-uclass.h>
10 #include <dm.h>
11 #include <regmap.h>
12 #include <syscon.h>
13 #include <asm/io.h>
14 #include <dm/root.h>
15 
16 #include <dt-bindings/clock/stm32h7-clks.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 /* RCC CR specific definitions */
21 #define RCC_CR_HSION			BIT(0)
22 #define RCC_CR_HSIRDY			BIT(2)
23 
24 #define RCC_CR_HSEON			BIT(16)
25 #define RCC_CR_HSERDY			BIT(17)
26 #define RCC_CR_HSEBYP			BIT(18)
27 #define RCC_CR_PLL1ON			BIT(24)
28 #define RCC_CR_PLL1RDY			BIT(25)
29 
30 #define RCC_CR_HSIDIV_MASK		GENMASK(4, 3)
31 #define RCC_CR_HSIDIV_SHIFT		3
32 
33 #define RCC_CFGR_SW_MASK		GENMASK(2, 0)
34 #define RCC_CFGR_SW_HSI			0
35 #define RCC_CFGR_SW_CSI			1
36 #define RCC_CFGR_SW_HSE			2
37 #define RCC_CFGR_SW_PLL1		3
38 #define RCC_CFGR_TIMPRE			BIT(15)
39 
40 #define RCC_PLLCKSELR_PLLSRC_HSI	0
41 #define RCC_PLLCKSELR_PLLSRC_CSI	1
42 #define RCC_PLLCKSELR_PLLSRC_HSE	2
43 #define RCC_PLLCKSELR_PLLSRC_NO_CLK	3
44 
45 #define RCC_PLLCKSELR_PLLSRC_MASK	GENMASK(1, 0)
46 
47 #define RCC_PLLCKSELR_DIVM1_SHIFT	4
48 #define RCC_PLLCKSELR_DIVM1_MASK	GENMASK(9, 4)
49 
50 #define RCC_PLL1DIVR_DIVN1_MASK		GENMASK(8, 0)
51 
52 #define RCC_PLL1DIVR_DIVP1_SHIFT	9
53 #define RCC_PLL1DIVR_DIVP1_MASK		GENMASK(15, 9)
54 
55 #define RCC_PLL1DIVR_DIVQ1_SHIFT	16
56 #define RCC_PLL1DIVR_DIVQ1_MASK		GENMASK(22, 16)
57 
58 #define RCC_PLL1DIVR_DIVR1_SHIFT	24
59 #define RCC_PLL1DIVR_DIVR1_MASK		GENMASK(30, 24)
60 
61 #define RCC_PLL1FRACR_FRACN1_SHIFT	3
62 #define RCC_PLL1FRACR_FRACN1_MASK	GENMASK(15, 3)
63 
64 #define RCC_PLLCFGR_PLL1RGE_SHIFT	2
65 #define		PLL1RGE_1_2_MHZ		0
66 #define		PLL1RGE_2_4_MHZ		1
67 #define		PLL1RGE_4_8_MHZ		2
68 #define		PLL1RGE_8_16_MHZ	3
69 #define RCC_PLLCFGR_DIVP1EN		BIT(16)
70 #define RCC_PLLCFGR_DIVQ1EN		BIT(17)
71 #define RCC_PLLCFGR_DIVR1EN		BIT(18)
72 
73 #define RCC_D1CFGR_HPRE_MASK		GENMASK(3, 0)
74 #define RCC_D1CFGR_HPRE_DIVIDED		BIT(3)
75 #define RCC_D1CFGR_HPRE_DIVIDER		GENMASK(2, 0)
76 
77 #define RCC_D1CFGR_HPRE_DIV2		8
78 
79 #define RCC_D1CFGR_D1PPRE_SHIFT		4
80 #define RCC_D1CFGR_D1PPRE_DIVIDED	BIT(6)
81 #define RCC_D1CFGR_D1PPRE_DIVIDER	GENMASK(5, 4)
82 
83 #define RCC_D1CFGR_D1CPRE_SHIFT		8
84 #define RCC_D1CFGR_D1CPRE_DIVIDER	GENMASK(10, 8)
85 #define RCC_D1CFGR_D1CPRE_DIVIDED	BIT(11)
86 
87 #define RCC_D2CFGR_D2PPRE1_SHIFT	4
88 #define RCC_D2CFGR_D2PPRE1_DIVIDED	BIT(6)
89 #define RCC_D2CFGR_D2PPRE1_DIVIDER	GENMASK(5, 4)
90 
91 #define RCC_D2CFGR_D2PPRE2_SHIFT	8
92 #define RCC_D2CFGR_D2PPRE2_DIVIDED	BIT(10)
93 #define RCC_D2CFGR_D2PPRE2_DIVIDER	GENMASK(9, 8)
94 
95 #define RCC_D3CFGR_D3PPRE_SHIFT		4
96 #define RCC_D3CFGR_D3PPRE_DIVIDED	BIT(6)
97 #define RCC_D3CFGR_D3PPRE_DIVIDER	GENMASK(5, 4)
98 
99 #define RCC_D1CCIPR_FMCSRC_MASK		GENMASK(1, 0)
100 #define		FMCSRC_HCLKD1		0
101 #define		FMCSRC_PLL1_Q_CK	1
102 #define		FMCSRC_PLL2_R_CK	2
103 #define		FMCSRC_PER_CK		3
104 
105 #define RCC_D1CCIPR_QSPISRC_MASK	GENMASK(5, 4)
106 #define RCC_D1CCIPR_QSPISRC_SHIFT	4
107 #define		QSPISRC_HCLKD1		0
108 #define		QSPISRC_PLL1_Q_CK	1
109 #define		QSPISRC_PLL2_R_CK	2
110 #define		QSPISRC_PER_CK		3
111 
112 #define PWR_CR3				0x0c
113 #define PWR_CR3_SCUEN			BIT(2)
114 #define PWR_D3CR			0x18
115 #define PWR_D3CR_VOS_MASK		GENMASK(15, 14)
116 #define PWR_D3CR_VOS_SHIFT		14
117 #define		VOS_SCALE_3		1
118 #define		VOS_SCALE_2		2
119 #define		VOS_SCALE_1		3
120 #define PWR_D3CR_VOSREADY		BIT(13)
121 
122 struct stm32_rcc_regs {
123 	u32 cr;		/* 0x00 Source Control Register */
124 	u32 icscr;	/* 0x04 Internal Clock Source Calibration Register */
125 	u32 crrcr;	/* 0x08 Clock Recovery RC Register */
126 	u32 reserved1;	/* 0x0c reserved */
127 	u32 cfgr;	/* 0x10 Clock Configuration Register */
128 	u32 reserved2;	/* 0x14 reserved */
129 	u32 d1cfgr;	/* 0x18 Domain 1 Clock Configuration Register */
130 	u32 d2cfgr;	/* 0x1c Domain 2 Clock Configuration Register */
131 	u32 d3cfgr;	/* 0x20 Domain 3 Clock Configuration Register */
132 	u32 reserved3;	/* 0x24 reserved */
133 	u32 pllckselr;	/* 0x28 PLLs Clock Source Selection Register */
134 	u32 pllcfgr;	/* 0x2c PLLs Configuration Register */
135 	u32 pll1divr;	/* 0x30 PLL1 Dividers Configuration Register */
136 	u32 pll1fracr;	/* 0x34 PLL1 Fractional Divider Register */
137 	u32 pll2divr;	/* 0x38 PLL2 Dividers Configuration Register */
138 	u32 pll2fracr;	/* 0x3c PLL2 Fractional Divider Register */
139 	u32 pll3divr;	/* 0x40 PLL3 Dividers Configuration Register */
140 	u32 pll3fracr;	/* 0x44 PLL3 Fractional Divider Register */
141 	u32 reserved4;	/* 0x48 reserved */
142 	u32 d1ccipr;	/* 0x4c Domain 1 Kernel Clock Configuration Register */
143 	u32 d2ccip1r;	/* 0x50 Domain 2 Kernel Clock Configuration Register */
144 	u32 d2ccip2r;	/* 0x54 Domain 2 Kernel Clock Configuration Register */
145 	u32 d3ccipr;	/* 0x58 Domain 3 Kernel Clock Configuration Register */
146 	u32 reserved5;	/* 0x5c reserved */
147 	u32 cier;	/* 0x60 Clock Source Interrupt Enable Register */
148 	u32 cifr;	/* 0x64 Clock Source Interrupt Flag Register */
149 	u32 cicr;	/* 0x68 Clock Source Interrupt Clear Register */
150 	u32 reserved6;	/* 0x6c reserved */
151 	u32 bdcr;	/* 0x70 Backup Domain Control Register */
152 	u32 csr;	/* 0x74 Clock Control and Status Register */
153 	u32 reserved7;	/* 0x78 reserved */
154 
155 	u32 ahb3rstr;	/* 0x7c AHB3 Peripheral Reset Register */
156 	u32 ahb1rstr;	/* 0x80 AHB1 Peripheral Reset Register */
157 	u32 ahb2rstr;	/* 0x84 AHB2 Peripheral Reset Register */
158 	u32 ahb4rstr;	/* 0x88 AHB4 Peripheral Reset Register */
159 
160 	u32 apb3rstr;	/* 0x8c APB3 Peripheral Reset Register */
161 	u32 apb1lrstr;	/* 0x90 APB1 low Peripheral Reset Register */
162 	u32 apb1hrstr;	/* 0x94 APB1 high Peripheral Reset Register */
163 	u32 apb2rstr;	/* 0x98 APB2 Clock Register */
164 	u32 apb4rstr;	/* 0x9c APB4 Clock Register */
165 
166 	u32 gcr;	/* 0xa0 Global Control Register */
167 	u32 reserved8;	/* 0xa4 reserved */
168 	u32 d3amr;	/* 0xa8 D3 Autonomous mode Register */
169 	u32 reserved9[9];/* 0xac to 0xcc reserved */
170 	u32 rsr;	/* 0xd0 Reset Status Register */
171 	u32 ahb3enr;	/* 0xd4 AHB3 Clock Register */
172 	u32 ahb1enr;	/* 0xd8 AHB1 Clock Register */
173 	u32 ahb2enr;	/* 0xdc AHB2 Clock Register */
174 	u32 ahb4enr;	/* 0xe0 AHB4 Clock Register */
175 
176 	u32 apb3enr;	/* 0xe4 APB3 Clock Register */
177 	u32 apb1lenr;	/* 0xe8 APB1 low Clock Register */
178 	u32 apb1henr;	/* 0xec APB1 high Clock Register */
179 	u32 apb2enr;	/* 0xf0 APB2 Clock Register */
180 	u32 apb4enr;	/* 0xf4 APB4 Clock Register */
181 };
182 
183 #define RCC_AHB3ENR	offsetof(struct stm32_rcc_regs, ahb3enr)
184 #define RCC_AHB1ENR	offsetof(struct stm32_rcc_regs, ahb1enr)
185 #define RCC_AHB2ENR	offsetof(struct stm32_rcc_regs, ahb2enr)
186 #define RCC_AHB4ENR	offsetof(struct stm32_rcc_regs, ahb4enr)
187 #define RCC_APB3ENR	offsetof(struct stm32_rcc_regs, apb3enr)
188 #define RCC_APB1LENR	offsetof(struct stm32_rcc_regs, apb1lenr)
189 #define RCC_APB1HENR	offsetof(struct stm32_rcc_regs, apb1henr)
190 #define RCC_APB2ENR	offsetof(struct stm32_rcc_regs, apb2enr)
191 #define RCC_APB4ENR	offsetof(struct stm32_rcc_regs, apb4enr)
192 
193 struct clk_cfg {
194 	u32 gate_offset;
195 	u8  gate_bit_idx;
196 	const char *name;
197 };
198 
199 /*
200  * the way all these entries are sorted in this array could seem
201  * unlogical, but we are dependant of kernel DT_bindings,
202  * where clocks are separate in 2 banks, peripheral clocks and
203  * kernel clocks.
204  */
205 
206 static const struct clk_cfg clk_map[] = {
207 	{RCC_AHB3ENR,  31, "d1sram1"},	/* peripheral clocks */
208 	{RCC_AHB3ENR,  30, "itcm"},
209 	{RCC_AHB3ENR,  29, "dtcm2"},
210 	{RCC_AHB3ENR,  28, "dtcm1"},
211 	{RCC_AHB3ENR,   8, "flitf"},
212 	{RCC_AHB3ENR,   5, "jpgdec"},
213 	{RCC_AHB3ENR,   4, "dma2d"},
214 	{RCC_AHB3ENR,   0, "mdma"},
215 	{RCC_AHB1ENR,  28, "usb2ulpi"},
216 	{RCC_AHB1ENR,  17, "eth1rx"},
217 	{RCC_AHB1ENR,  16, "eth1tx"},
218 	{RCC_AHB1ENR,  15, "eth1mac"},
219 	{RCC_AHB1ENR,  14, "art"},
220 	{RCC_AHB1ENR,  26, "usb1ulpi"},
221 	{RCC_AHB1ENR,   1, "dma2"},
222 	{RCC_AHB1ENR,   0, "dma1"},
223 	{RCC_AHB2ENR,  31, "d2sram3"},
224 	{RCC_AHB2ENR,  30, "d2sram2"},
225 	{RCC_AHB2ENR,  29, "d2sram1"},
226 	{RCC_AHB2ENR,   5, "hash"},
227 	{RCC_AHB2ENR,   4, "crypt"},
228 	{RCC_AHB2ENR,   0, "camitf"},
229 	{RCC_AHB4ENR,  28, "bkpram"},
230 	{RCC_AHB4ENR,  25, "hsem"},
231 	{RCC_AHB4ENR,  21, "bdma"},
232 	{RCC_AHB4ENR,  19, "crc"},
233 	{RCC_AHB4ENR,  10, "gpiok"},
234 	{RCC_AHB4ENR,   9, "gpioj"},
235 	{RCC_AHB4ENR,   8, "gpioi"},
236 	{RCC_AHB4ENR,   7, "gpioh"},
237 	{RCC_AHB4ENR,   6, "gpiog"},
238 	{RCC_AHB4ENR,   5, "gpiof"},
239 	{RCC_AHB4ENR,   4, "gpioe"},
240 	{RCC_AHB4ENR,   3, "gpiod"},
241 	{RCC_AHB4ENR,   2, "gpioc"},
242 	{RCC_AHB4ENR,   1, "gpiob"},
243 	{RCC_AHB4ENR,   0, "gpioa"},
244 	{RCC_APB3ENR,   6, "wwdg1"},
245 	{RCC_APB1LENR, 29, "dac12"},
246 	{RCC_APB1LENR, 11, "wwdg2"},
247 	{RCC_APB1LENR,  8, "tim14"},
248 	{RCC_APB1LENR,  7, "tim13"},
249 	{RCC_APB1LENR,  6, "tim12"},
250 	{RCC_APB1LENR,  5, "tim7"},
251 	{RCC_APB1LENR,  4, "tim6"},
252 	{RCC_APB1LENR,  3, "tim5"},
253 	{RCC_APB1LENR,  2, "tim4"},
254 	{RCC_APB1LENR,  1, "tim3"},
255 	{RCC_APB1LENR,  0, "tim2"},
256 	{RCC_APB1HENR,  5, "mdios"},
257 	{RCC_APB1HENR,  4, "opamp"},
258 	{RCC_APB1HENR,  1, "crs"},
259 	{RCC_APB2ENR,  18, "tim17"},
260 	{RCC_APB2ENR,  17, "tim16"},
261 	{RCC_APB2ENR,  16, "tim15"},
262 	{RCC_APB2ENR,   1, "tim8"},
263 	{RCC_APB2ENR,   0, "tim1"},
264 	{RCC_APB4ENR,  26, "tmpsens"},
265 	{RCC_APB4ENR,  16, "rtcapb"},
266 	{RCC_APB4ENR,  15, "vref"},
267 	{RCC_APB4ENR,  14, "comp12"},
268 	{RCC_APB4ENR,   1, "syscfg"},
269 	{RCC_AHB3ENR,  16, "sdmmc1"},	/* kernel clocks */
270 	{RCC_AHB3ENR,  14, "quadspi"},
271 	{RCC_AHB3ENR,  12, "fmc"},
272 	{RCC_AHB1ENR,  27, "usb2otg"},
273 	{RCC_AHB1ENR,  25, "usb1otg"},
274 	{RCC_AHB1ENR,   5, "adc12"},
275 	{RCC_AHB2ENR,   9, "sdmmc2"},
276 	{RCC_AHB2ENR,   6, "rng"},
277 	{RCC_AHB4ENR,  24, "adc3"},
278 	{RCC_APB3ENR,   4, "dsi"},
279 	{RCC_APB3ENR,   3, "ltdc"},
280 	{RCC_APB1LENR, 31, "usart8"},
281 	{RCC_APB1LENR, 30, "usart7"},
282 	{RCC_APB1LENR, 27, "hdmicec"},
283 	{RCC_APB1LENR, 23, "i2c3"},
284 	{RCC_APB1LENR, 22, "i2c2"},
285 	{RCC_APB1LENR, 21, "i2c1"},
286 	{RCC_APB1LENR, 20, "uart5"},
287 	{RCC_APB1LENR, 19, "uart4"},
288 	{RCC_APB1LENR, 18, "usart3"},
289 	{RCC_APB1LENR, 17, "usart2"},
290 	{RCC_APB1LENR, 16, "spdifrx"},
291 	{RCC_APB1LENR, 15, "spi3"},
292 	{RCC_APB1LENR, 14, "spi2"},
293 	{RCC_APB1LENR,  9, "lptim1"},
294 	{RCC_APB1HENR,  8, "fdcan"},
295 	{RCC_APB1HENR,  2, "swp"},
296 	{RCC_APB2ENR,  29, "hrtim"},
297 	{RCC_APB2ENR,  28, "dfsdm1"},
298 	{RCC_APB2ENR,  24, "sai3"},
299 	{RCC_APB2ENR,  23, "sai2"},
300 	{RCC_APB2ENR,  22, "sai1"},
301 	{RCC_APB2ENR,  20, "spi5"},
302 	{RCC_APB2ENR,  13, "spi4"},
303 	{RCC_APB2ENR,  12, "spi1"},
304 	{RCC_APB2ENR,   5, "usart6"},
305 	{RCC_APB2ENR,   4, "usart1"},
306 	{RCC_APB4ENR,  21, "sai4a"},
307 	{RCC_APB4ENR,  21, "sai4b"},
308 	{RCC_APB4ENR,  12, "lptim5"},
309 	{RCC_APB4ENR,  11, "lptim4"},
310 	{RCC_APB4ENR,  10, "lptim3"},
311 	{RCC_APB4ENR,   9, "lptim2"},
312 	{RCC_APB4ENR,   7, "i2c4"},
313 	{RCC_APB4ENR,   5,  "spi6"},
314 	{RCC_APB4ENR,   3, "lpuart1"},
315 };
316 
317 struct stm32_clk {
318 	struct stm32_rcc_regs *rcc_base;
319 	struct regmap *pwr_regmap;
320 };
321 
322 struct pll_psc {
323 	u8	divm;
324 	u16	divn;
325 	u8	divp;
326 	u8	divq;
327 	u8	divr;
328 };
329 
330 /*
331  * OSC_HSE = 25 MHz
332  * VCO = 500MHz
333  * pll1_p = 250MHz / pll1_q = 250MHz pll1_r = 250Mhz
334  */
335 struct pll_psc sys_pll_psc = {
336 	.divm = 4,
337 	.divn = 80,
338 	.divp = 2,
339 	.divq = 2,
340 	.divr = 2,
341 };
342 
343 enum apb {
344 	APB1,
345 	APB2,
346 };
347 
348 int configure_clocks(struct udevice *dev)
349 {
350 	struct stm32_clk *priv = dev_get_priv(dev);
351 	struct stm32_rcc_regs *regs = priv->rcc_base;
352 	uint8_t *pwr_base = (uint8_t *)regmap_get_range(priv->pwr_regmap, 0);
353 	uint32_t pllckselr = 0;
354 	uint32_t pll1divr = 0;
355 	uint32_t pllcfgr = 0;
356 
357 	/* Switch on HSI */
358 	setbits_le32(&regs->cr, RCC_CR_HSION);
359 	while (!(readl(&regs->cr) & RCC_CR_HSIRDY))
360 		;
361 
362 	/* Reset CFGR, now HSI is the default system clock */
363 	writel(0, &regs->cfgr);
364 
365 	/* Set all kernel domain clock registers to reset value*/
366 	writel(0x0, &regs->d1ccipr);
367 	writel(0x0, &regs->d2ccip1r);
368 	writel(0x0, &regs->d2ccip2r);
369 
370 	/* Set voltage scaling at scale 1 (1,15 - 1,26 Volts) */
371 	clrsetbits_le32(pwr_base + PWR_D3CR, PWR_D3CR_VOS_MASK,
372 			VOS_SCALE_1 << PWR_D3CR_VOS_SHIFT);
373 	/* Lock supply configuration update */
374 	clrbits_le32(pwr_base + PWR_CR3, PWR_CR3_SCUEN);
375 	while (!(readl(pwr_base + PWR_D3CR) & PWR_D3CR_VOSREADY))
376 		;
377 
378 	/* disable HSE to configure it  */
379 	clrbits_le32(&regs->cr, RCC_CR_HSEON);
380 	while ((readl(&regs->cr) & RCC_CR_HSERDY))
381 		;
382 
383 	/* clear HSE bypass and set it ON */
384 	clrbits_le32(&regs->cr, RCC_CR_HSEBYP);
385 	/* Switch on HSE */
386 	setbits_le32(&regs->cr, RCC_CR_HSEON);
387 	while (!(readl(&regs->cr) & RCC_CR_HSERDY))
388 		;
389 
390 	/* pll setup, disable it */
391 	clrbits_le32(&regs->cr, RCC_CR_PLL1ON);
392 	while ((readl(&regs->cr) & RCC_CR_PLL1RDY))
393 		;
394 
395 	/* Select HSE as PLL clock source */
396 	pllckselr |= RCC_PLLCKSELR_PLLSRC_HSE;
397 	pllckselr |= sys_pll_psc.divm << RCC_PLLCKSELR_DIVM1_SHIFT;
398 	writel(pllckselr, &regs->pllckselr);
399 
400 	pll1divr |= (sys_pll_psc.divr - 1) << RCC_PLL1DIVR_DIVR1_SHIFT;
401 	pll1divr |= (sys_pll_psc.divq - 1) << RCC_PLL1DIVR_DIVQ1_SHIFT;
402 	pll1divr |= (sys_pll_psc.divp - 1) << RCC_PLL1DIVR_DIVP1_SHIFT;
403 	pll1divr |= (sys_pll_psc.divn - 1);
404 	writel(pll1divr, &regs->pll1divr);
405 
406 	pllcfgr |= PLL1RGE_4_8_MHZ << RCC_PLLCFGR_PLL1RGE_SHIFT;
407 	pllcfgr |= RCC_PLLCFGR_DIVP1EN;
408 	pllcfgr |= RCC_PLLCFGR_DIVQ1EN;
409 	pllcfgr |= RCC_PLLCFGR_DIVR1EN;
410 	writel(pllcfgr, &regs->pllcfgr);
411 
412 	/* pll setup, enable it */
413 	setbits_le32(&regs->cr, RCC_CR_PLL1ON);
414 
415 	/* set HPRE (/2) DI clk --> 125MHz */
416 	clrsetbits_le32(&regs->d1cfgr, RCC_D1CFGR_HPRE_MASK,
417 			RCC_D1CFGR_HPRE_DIV2);
418 
419 	/*  select PLL1 as system clock source (sys_ck)*/
420 	clrsetbits_le32(&regs->cfgr, RCC_CFGR_SW_MASK, RCC_CFGR_SW_PLL1);
421 	while ((readl(&regs->cfgr) & RCC_CFGR_SW_MASK) != RCC_CFGR_SW_PLL1)
422 		;
423 
424 	/* sdram: use pll1_q as fmc_k clk */
425 	clrsetbits_le32(&regs->d1ccipr, RCC_D1CCIPR_FMCSRC_MASK,
426 			FMCSRC_PLL1_Q_CK);
427 
428 	return 0;
429 }
430 
431 static u32 stm32_get_HSI_divider(struct stm32_rcc_regs *regs)
432 {
433 	u32 divider;
434 
435 	/* get HSI divider value */
436 	divider = readl(&regs->cr) & RCC_CR_HSIDIV_MASK;
437 	divider = divider >> RCC_CR_HSIDIV_SHIFT;
438 
439 	return divider;
440 };
441 
442 enum pllsrc {
443 	HSE,
444 	LSE,
445 	HSI,
446 	CSI,
447 	I2S,
448 	TIMER,
449 	PLLSRC_NB,
450 };
451 
452 static const char * const pllsrc_name[PLLSRC_NB] = {
453 	[HSE] = "clk-hse",
454 	[LSE] = "clk-lse",
455 	[HSI] = "clk-hsi",
456 	[CSI] = "clk-csi",
457 	[I2S] = "clk-i2s",
458 	[TIMER] = "timer-clk"
459 };
460 
461 static ulong stm32_get_rate(struct stm32_rcc_regs *regs, enum pllsrc pllsrc)
462 {
463 	struct clk clk;
464 	struct udevice *fixed_clock_dev = NULL;
465 	u32 divider;
466 	int ret;
467 	const char *name = pllsrc_name[pllsrc];
468 
469 	debug("%s name %s\n", __func__, name);
470 
471 	clk.id = 0;
472 	ret = uclass_get_device_by_name(UCLASS_CLK, name, &fixed_clock_dev);
473 	if (ret) {
474 		pr_err("Can't find clk %s (%d)", name, ret);
475 		return 0;
476 	}
477 
478 	ret = clk_request(fixed_clock_dev, &clk);
479 	if (ret) {
480 		pr_err("Can't request %s clk (%d)", name, ret);
481 		return 0;
482 	}
483 
484 	divider = 0;
485 	if (pllsrc == HSI)
486 		divider = stm32_get_HSI_divider(regs);
487 
488 	debug("%s divider %d rate %ld\n", __func__,
489 	      divider, clk_get_rate(&clk));
490 
491 	return clk_get_rate(&clk) >> divider;
492 };
493 
494 enum pll1_output {
495 	PLL1_P_CK,
496 	PLL1_Q_CK,
497 	PLL1_R_CK,
498 };
499 
500 static u32 stm32_get_PLL1_rate(struct stm32_rcc_regs *regs,
501 			       enum pll1_output output)
502 {
503 	ulong pllsrc = 0;
504 	u32 divm1, divn1, divp1, divq1, divr1, fracn1;
505 	ulong vco, rate;
506 
507 	/* get the PLLSRC */
508 	switch (readl(&regs->pllckselr) & RCC_PLLCKSELR_PLLSRC_MASK) {
509 	case RCC_PLLCKSELR_PLLSRC_HSI:
510 		pllsrc = stm32_get_rate(regs, HSI);
511 		break;
512 	case RCC_PLLCKSELR_PLLSRC_CSI:
513 		pllsrc = stm32_get_rate(regs, CSI);
514 		break;
515 	case RCC_PLLCKSELR_PLLSRC_HSE:
516 		pllsrc = stm32_get_rate(regs, HSE);
517 		break;
518 	case RCC_PLLCKSELR_PLLSRC_NO_CLK:
519 		/* shouldn't happen */
520 		pr_err("wrong value for RCC_PLLCKSELR register\n");
521 		pllsrc = 0;
522 		break;
523 	}
524 
525 	/* pllsrc = 0 ? no need to go ahead */
526 	if (!pllsrc)
527 		return pllsrc;
528 
529 	/* get divm1, divp1, divn1 and divr1 */
530 	divm1 = readl(&regs->pllckselr) & RCC_PLLCKSELR_DIVM1_MASK;
531 	divm1 = divm1 >> RCC_PLLCKSELR_DIVM1_SHIFT;
532 
533 	divn1 = (readl(&regs->pll1divr) & RCC_PLL1DIVR_DIVN1_MASK) + 1;
534 
535 	divp1 = readl(&regs->pll1divr) & RCC_PLL1DIVR_DIVP1_MASK;
536 	divp1 = (divp1 >> RCC_PLL1DIVR_DIVP1_SHIFT) + 1;
537 
538 	divq1 = readl(&regs->pll1divr) & RCC_PLL1DIVR_DIVQ1_MASK;
539 	divq1 = (divq1 >> RCC_PLL1DIVR_DIVQ1_SHIFT) + 1;
540 
541 	divr1 = readl(&regs->pll1divr) & RCC_PLL1DIVR_DIVR1_MASK;
542 	divr1 = (divr1 >> RCC_PLL1DIVR_DIVR1_SHIFT) + 1;
543 
544 	fracn1 = readl(&regs->pll1fracr) & RCC_PLL1DIVR_DIVR1_MASK;
545 	fracn1 = fracn1 & RCC_PLL1DIVR_DIVR1_SHIFT;
546 
547 	vco = (pllsrc / divm1) * divn1;
548 	rate = (pllsrc * fracn1) / (divm1 * 8192);
549 
550 	debug("%s divm1 = %d divn1 = %d divp1 = %d divq1 = %d divr1 = %d\n",
551 	      __func__, divm1, divn1, divp1, divq1, divr1);
552 	debug("%s fracn1 = %d vco = %ld rate = %ld\n",
553 	      __func__, fracn1, vco, rate);
554 
555 	switch (output) {
556 	case PLL1_P_CK:
557 		return (vco + rate) / divp1;
558 		break;
559 	case PLL1_Q_CK:
560 		return (vco + rate) / divq1;
561 		break;
562 
563 	case PLL1_R_CK:
564 		return (vco + rate) / divr1;
565 		break;
566 	}
567 
568 	return -EINVAL;
569 }
570 
571 static u32 stm32_get_apb_psc(struct stm32_rcc_regs *regs, enum apb apb)
572 {
573 	u16 prescaler_table[8] = {2, 4, 8, 16, 64, 128, 256, 512};
574 	u32 d2cfgr = readl(&regs->d2cfgr);
575 
576 	if (apb == APB1) {
577 		if (d2cfgr & RCC_D2CFGR_D2PPRE1_DIVIDED)
578 			/* get D2 domain APB1 prescaler */
579 			return prescaler_table[
580 				((d2cfgr & RCC_D2CFGR_D2PPRE1_DIVIDER)
581 				>> RCC_D2CFGR_D2PPRE1_SHIFT)];
582 	} else  { /* APB2 */
583 		if (d2cfgr & RCC_D2CFGR_D2PPRE2_DIVIDED)
584 			/* get D2 domain APB2 prescaler */
585 			return prescaler_table[
586 				((d2cfgr & RCC_D2CFGR_D2PPRE2_DIVIDER)
587 				>> RCC_D2CFGR_D2PPRE2_SHIFT)];
588 	}
589 
590 	return 1;
591 };
592 
593 static u32 stm32_get_timer_rate(struct stm32_clk *priv, u32 sysclk,
594 				enum apb apb)
595 {
596 	struct stm32_rcc_regs *regs = priv->rcc_base;
597 u32 psc = stm32_get_apb_psc(regs, apb);
598 
599 	if (readl(&regs->cfgr) & RCC_CFGR_TIMPRE)
600 		/*
601 		 * if APB prescaler is configured to a
602 		 * division factor of 1, 2 or 4
603 		 */
604 		switch (psc) {
605 		case 1:
606 		case 2:
607 		case 4:
608 			return sysclk;
609 		case 8:
610 			return sysclk / 2;
611 		case 16:
612 			return sysclk / 4;
613 		default:
614 			pr_err("unexpected prescaler value (%d)\n", psc);
615 			return 0;
616 		}
617 	else
618 		switch (psc) {
619 		case 1:
620 			return sysclk;
621 		case 2:
622 		case 4:
623 		case 8:
624 		case 16:
625 			return sysclk / psc;
626 		default:
627 			pr_err("unexpected prescaler value (%d)\n", psc);
628 			return 0;
629 		}
630 };
631 
632 static ulong stm32_clk_get_rate(struct clk *clk)
633 {
634 	struct stm32_clk *priv = dev_get_priv(clk->dev);
635 	struct stm32_rcc_regs *regs = priv->rcc_base;
636 	ulong sysclk = 0;
637 	u32 gate_offset;
638 	u32 d1cfgr, d3cfgr;
639 	/* prescaler table lookups for clock computation */
640 	u16 prescaler_table[8] = {2, 4, 8, 16, 64, 128, 256, 512};
641 	u8 source, idx;
642 
643 	/*
644 	 * get system clock (sys_ck) source
645 	 * can be HSI_CK, CSI_CK, HSE_CK or pll1_p_ck
646 	 */
647 	source = readl(&regs->cfgr) & RCC_CFGR_SW_MASK;
648 	switch (source) {
649 	case RCC_CFGR_SW_PLL1:
650 		sysclk = stm32_get_PLL1_rate(regs, PLL1_P_CK);
651 		break;
652 	case RCC_CFGR_SW_HSE:
653 		sysclk = stm32_get_rate(regs, HSE);
654 		break;
655 
656 	case RCC_CFGR_SW_CSI:
657 		sysclk = stm32_get_rate(regs, CSI);
658 		break;
659 
660 	case RCC_CFGR_SW_HSI:
661 		sysclk = stm32_get_rate(regs, HSI);
662 		break;
663 	}
664 
665 	/* sysclk = 0 ? no need to go ahead */
666 	if (!sysclk)
667 		return sysclk;
668 
669 	debug("%s system clock: source = %d freq = %ld\n",
670 	      __func__, source, sysclk);
671 
672 	d1cfgr = readl(&regs->d1cfgr);
673 
674 	if (d1cfgr & RCC_D1CFGR_D1CPRE_DIVIDED) {
675 		/* get D1 domain Core prescaler */
676 		idx = (d1cfgr & RCC_D1CFGR_D1CPRE_DIVIDER) >>
677 		      RCC_D1CFGR_D1CPRE_SHIFT;
678 		sysclk = sysclk / prescaler_table[idx];
679 	}
680 
681 	if (d1cfgr & RCC_D1CFGR_HPRE_DIVIDED) {
682 		/* get D1 domain AHB prescaler */
683 		idx = d1cfgr & RCC_D1CFGR_HPRE_DIVIDER;
684 		sysclk = sysclk / prescaler_table[idx];
685 	}
686 
687 	gate_offset = clk_map[clk->id].gate_offset;
688 
689 	debug("%s clk->id=%ld gate_offset=0x%x sysclk=%ld\n",
690 	      __func__, clk->id, gate_offset, sysclk);
691 
692 	switch (gate_offset) {
693 	case RCC_AHB3ENR:
694 	case RCC_AHB1ENR:
695 	case RCC_AHB2ENR:
696 	case RCC_AHB4ENR:
697 		return sysclk;
698 		break;
699 
700 	case RCC_APB3ENR:
701 		if (d1cfgr & RCC_D1CFGR_D1PPRE_DIVIDED) {
702 			/* get D1 domain APB3 prescaler */
703 			idx = (d1cfgr & RCC_D1CFGR_D1PPRE_DIVIDER) >>
704 			      RCC_D1CFGR_D1PPRE_SHIFT;
705 			sysclk = sysclk / prescaler_table[idx];
706 		}
707 
708 		debug("%s system clock: freq after APB3 prescaler = %ld\n",
709 		      __func__, sysclk);
710 
711 		return sysclk;
712 		break;
713 
714 	case RCC_APB4ENR:
715 		d3cfgr = readl(&regs->d3cfgr);
716 		if (d3cfgr & RCC_D3CFGR_D3PPRE_DIVIDED) {
717 			/* get D3 domain APB4 prescaler */
718 			idx = (d3cfgr & RCC_D3CFGR_D3PPRE_DIVIDER) >>
719 			      RCC_D3CFGR_D3PPRE_SHIFT;
720 			sysclk = sysclk / prescaler_table[idx];
721 		}
722 
723 		debug("%s system clock: freq after APB4 prescaler = %ld\n",
724 		      __func__, sysclk);
725 
726 		return sysclk;
727 		break;
728 
729 	case RCC_APB1LENR:
730 	case RCC_APB1HENR:
731 		/* special case for GPT timers */
732 		switch (clk->id) {
733 		case TIM14_CK:
734 		case TIM13_CK:
735 		case TIM12_CK:
736 		case TIM7_CK:
737 		case TIM6_CK:
738 		case TIM5_CK:
739 		case TIM4_CK:
740 		case TIM3_CK:
741 		case TIM2_CK:
742 			return stm32_get_timer_rate(priv, sysclk, APB1);
743 		}
744 
745 		debug("%s system clock: freq after APB1 prescaler = %ld\n",
746 		      __func__, sysclk);
747 
748 		return (sysclk / stm32_get_apb_psc(regs, APB1));
749 		break;
750 
751 	case RCC_APB2ENR:
752 		/* special case for timers */
753 		switch (clk->id) {
754 		case TIM17_CK:
755 		case TIM16_CK:
756 		case TIM15_CK:
757 		case TIM8_CK:
758 		case TIM1_CK:
759 			return stm32_get_timer_rate(priv, sysclk, APB2);
760 		}
761 
762 		debug("%s system clock: freq after APB2 prescaler = %ld\n",
763 		      __func__, sysclk);
764 
765 		return (sysclk / stm32_get_apb_psc(regs, APB2));
766 
767 		break;
768 
769 	default:
770 		pr_err("unexpected gate_offset value (0x%x)\n", gate_offset);
771 		return -EINVAL;
772 		break;
773 	}
774 }
775 
776 static int stm32_clk_enable(struct clk *clk)
777 {
778 	struct stm32_clk *priv = dev_get_priv(clk->dev);
779 	struct stm32_rcc_regs *regs = priv->rcc_base;
780 	u32 gate_offset;
781 	u32 gate_bit_index;
782 	unsigned long clk_id = clk->id;
783 
784 	gate_offset = clk_map[clk_id].gate_offset;
785 	gate_bit_index = clk_map[clk_id].gate_bit_idx;
786 
787 	debug("%s: clkid=%ld gate offset=0x%x bit_index=%d name=%s\n",
788 	      __func__, clk->id, gate_offset, gate_bit_index,
789 	      clk_map[clk_id].name);
790 
791 	setbits_le32(&regs->cr + (gate_offset / 4), BIT(gate_bit_index));
792 
793 	return 0;
794 }
795 
796 static int stm32_clk_probe(struct udevice *dev)
797 {
798 	struct stm32_clk *priv = dev_get_priv(dev);
799 	struct udevice *syscon;
800 	fdt_addr_t addr;
801 	int err;
802 
803 	addr = dev_read_addr(dev);
804 	if (addr == FDT_ADDR_T_NONE)
805 		return -EINVAL;
806 
807 	priv->rcc_base = (struct stm32_rcc_regs *)addr;
808 
809 	/* get corresponding syscon phandle */
810 	err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
811 					   "st,syscfg", &syscon);
812 
813 	if (err) {
814 		pr_err("unable to find syscon device\n");
815 		return err;
816 	}
817 
818 	priv->pwr_regmap = syscon_get_regmap(syscon);
819 	if (!priv->pwr_regmap) {
820 		pr_err("unable to find regmap\n");
821 		return -ENODEV;
822 	}
823 
824 	configure_clocks(dev);
825 
826 	return 0;
827 }
828 
829 static int stm32_clk_of_xlate(struct clk *clk,
830 			struct ofnode_phandle_args *args)
831 {
832 	if (args->args_count != 1) {
833 		debug("Invaild args_count: %d\n", args->args_count);
834 		return -EINVAL;
835 	}
836 
837 	if (args->args_count) {
838 		clk->id = args->args[0];
839 		/*
840 		 * this computation convert DT clock index which is used to
841 		 * point into 2 separate clock arrays (peripheral and kernel
842 		 * clocks bank) (see include/dt-bindings/clock/stm32h7-clks.h)
843 		 * into index to point into only one array where peripheral
844 		 * and kernel clocks are consecutive
845 		 */
846 		if (clk->id >= KERN_BANK) {
847 			clk->id -= KERN_BANK;
848 			clk->id += LAST_PERIF_BANK - PERIF_BANK + 1;
849 		} else {
850 			clk->id -= PERIF_BANK;
851 		}
852 	} else {
853 		clk->id = 0;
854 	}
855 
856 	debug("%s clk->id %ld\n", __func__, clk->id);
857 
858 	return 0;
859 }
860 
861 static struct clk_ops stm32_clk_ops = {
862 	.of_xlate	= stm32_clk_of_xlate,
863 	.enable		= stm32_clk_enable,
864 	.get_rate	= stm32_clk_get_rate,
865 };
866 
867 U_BOOT_DRIVER(stm32h7_clk) = {
868 	.name			= "stm32h7_rcc_clock",
869 	.id			= UCLASS_CLK,
870 	.ops			= &stm32_clk_ops,
871 	.probe			= stm32_clk_probe,
872 	.priv_auto_alloc_size	= sizeof(struct stm32_clk),
873 	.flags			= DM_FLAG_PRE_RELOC,
874 };
875