xref: /rk3399_rockchip-uboot/arch/arm/mach-stm32/stm32f4/clock.c (revision 0785dfd8a7b14cb2c99fc1271c865eb2170c620b)
1 /*
2  * (C) Copyright 2015
3  * Kamil Lulko, <kamil.lulko@gmail.com>
4  *
5  * (C) Copyright 2014
6  * STMicroelectronics
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <asm/io.h>
13 #include <asm/arch/stm32.h>
14 
15 #define RCC_CR_HSION		(1 << 0)
16 #define RCC_CR_HSEON		(1 << 16)
17 #define RCC_CR_HSERDY		(1 << 17)
18 #define RCC_CR_HSEBYP		(1 << 18)
19 #define RCC_CR_CSSON		(1 << 19)
20 #define RCC_CR_PLLON		(1 << 24)
21 #define RCC_CR_PLLRDY		(1 << 25)
22 
23 #define RCC_PLLCFGR_PLLM_MASK	0x3F
24 #define RCC_PLLCFGR_PLLN_MASK	0x7FC0
25 #define RCC_PLLCFGR_PLLP_MASK	0x30000
26 #define RCC_PLLCFGR_PLLQ_MASK	0xF000000
27 #define RCC_PLLCFGR_PLLSRC	(1 << 22)
28 #define RCC_PLLCFGR_PLLN_SHIFT	6
29 #define RCC_PLLCFGR_PLLP_SHIFT	16
30 #define RCC_PLLCFGR_PLLQ_SHIFT	24
31 
32 #define RCC_CFGR_AHB_PSC_MASK	0xF0
33 #define RCC_CFGR_APB1_PSC_MASK	0x1C00
34 #define RCC_CFGR_APB2_PSC_MASK	0xE000
35 #define RCC_CFGR_SW0		(1 << 0)
36 #define RCC_CFGR_SW1		(1 << 1)
37 #define RCC_CFGR_SW_MASK	0x3
38 #define RCC_CFGR_SW_HSI		0
39 #define RCC_CFGR_SW_HSE		RCC_CFGR_SW0
40 #define RCC_CFGR_SW_PLL		RCC_CFGR_SW1
41 #define RCC_CFGR_SWS0		(1 << 2)
42 #define RCC_CFGR_SWS1		(1 << 3)
43 #define RCC_CFGR_SWS_MASK	0xC
44 #define RCC_CFGR_SWS_HSI	0
45 #define RCC_CFGR_SWS_HSE	RCC_CFGR_SWS0
46 #define RCC_CFGR_SWS_PLL	RCC_CFGR_SWS1
47 #define RCC_CFGR_HPRE_SHIFT	4
48 #define RCC_CFGR_PPRE1_SHIFT	10
49 #define RCC_CFGR_PPRE2_SHIFT	13
50 
51 #define RCC_APB1ENR_PWREN	(1 << 28)
52 
53 #define PWR_CR_VOS0		(1 << 14)
54 #define PWR_CR_VOS1		(1 << 15)
55 #define PWR_CR_VOS_MASK		0xC000
56 #define PWR_CR_VOS_SCALE_MODE_1	(PWR_CR_VOS0 | PWR_CR_VOS1)
57 #define PWR_CR_VOS_SCALE_MODE_2	(PWR_CR_VOS1)
58 #define PWR_CR_VOS_SCALE_MODE_3	(PWR_CR_VOS0)
59 
60 #define FLASH_ACR_WS(n)		n
61 #define FLASH_ACR_PRFTEN	(1 << 8)
62 #define FLASH_ACR_ICEN		(1 << 9)
63 #define FLASH_ACR_DCEN		(1 << 10)
64 
65 struct pll_psc {
66 	u8	pll_m;
67 	u16	pll_n;
68 	u8	pll_p;
69 	u8	pll_q;
70 	u8	ahb_psc;
71 	u8	apb1_psc;
72 	u8	apb2_psc;
73 };
74 
75 #define AHB_PSC_1		0
76 #define AHB_PSC_2		0x8
77 #define AHB_PSC_4		0x9
78 #define AHB_PSC_8		0xA
79 #define AHB_PSC_16		0xB
80 #define AHB_PSC_64		0xC
81 #define AHB_PSC_128		0xD
82 #define AHB_PSC_256		0xE
83 #define AHB_PSC_512		0xF
84 
85 #define APB_PSC_1		0
86 #define APB_PSC_2		0x4
87 #define APB_PSC_4		0x5
88 #define APB_PSC_8		0x6
89 #define APB_PSC_16		0x7
90 
91 #if !defined(CONFIG_STM32_HSE_HZ)
92 #error "CONFIG_STM32_HSE_HZ not defined!"
93 #else
94 #if (CONFIG_STM32_HSE_HZ == 8000000)
95 #if (CONFIG_SYS_CLK_FREQ == 180000000)
96 /* 180 MHz */
97 struct pll_psc sys_pll_psc = {
98 	.pll_m = 8,
99 	.pll_n = 360,
100 	.pll_p = 2,
101 	.pll_q = 8,
102 	.ahb_psc = AHB_PSC_1,
103 	.apb1_psc = APB_PSC_4,
104 	.apb2_psc = APB_PSC_2
105 };
106 #else
107 /* default 168 MHz */
108 struct pll_psc sys_pll_psc = {
109 	.pll_m = 8,
110 	.pll_n = 336,
111 	.pll_p = 2,
112 	.pll_q = 7,
113 	.ahb_psc = AHB_PSC_1,
114 	.apb1_psc = APB_PSC_4,
115 	.apb2_psc = APB_PSC_2
116 };
117 #endif
118 #else
119 #error "No PLL/Prescaler configuration for given CONFIG_STM32_HSE_HZ exists"
120 #endif
121 #endif
122 
123 int configure_clocks(void)
124 {
125 	/* Reset RCC configuration */
126 	setbits_le32(&STM32_RCC->cr, RCC_CR_HSION);
127 	writel(0, &STM32_RCC->cfgr); /* Reset CFGR */
128 	clrbits_le32(&STM32_RCC->cr, (RCC_CR_HSEON | RCC_CR_CSSON
129 		| RCC_CR_PLLON));
130 	writel(0x24003010, &STM32_RCC->pllcfgr); /* Reset value from RM */
131 	clrbits_le32(&STM32_RCC->cr, RCC_CR_HSEBYP);
132 	writel(0, &STM32_RCC->cir); /* Disable all interrupts */
133 
134 	/* Configure for HSE+PLL operation */
135 	setbits_le32(&STM32_RCC->cr, RCC_CR_HSEON);
136 	while (!(readl(&STM32_RCC->cr) & RCC_CR_HSERDY))
137 		;
138 
139 	/* Enable high performance mode, System frequency up to 180 MHz */
140 	setbits_le32(&STM32_RCC->apb1enr, RCC_APB1ENR_PWREN);
141 	writel(PWR_CR_VOS_SCALE_MODE_1, &STM32_PWR->cr);
142 
143 	setbits_le32(&STM32_RCC->cfgr, ((
144 		sys_pll_psc.ahb_psc << RCC_CFGR_HPRE_SHIFT)
145 		| (sys_pll_psc.apb1_psc << RCC_CFGR_PPRE1_SHIFT)
146 		| (sys_pll_psc.apb2_psc << RCC_CFGR_PPRE2_SHIFT)));
147 
148 	writel(sys_pll_psc.pll_m
149 		| (sys_pll_psc.pll_n << RCC_PLLCFGR_PLLN_SHIFT)
150 		| (((sys_pll_psc.pll_p >> 1) - 1) << RCC_PLLCFGR_PLLP_SHIFT)
151 		| (sys_pll_psc.pll_q << RCC_PLLCFGR_PLLQ_SHIFT),
152 		&STM32_RCC->pllcfgr);
153 	setbits_le32(&STM32_RCC->pllcfgr, RCC_PLLCFGR_PLLSRC);
154 
155 	setbits_le32(&STM32_RCC->cr, RCC_CR_PLLON);
156 
157 	while (!(readl(&STM32_RCC->cr) & RCC_CR_PLLRDY))
158 		;
159 
160 	/* 5 wait states, Prefetch enabled, D-Cache enabled, I-Cache enabled */
161 	writel(FLASH_ACR_WS(5) | FLASH_ACR_PRFTEN | FLASH_ACR_ICEN
162 		| FLASH_ACR_DCEN, &STM32_FLASH->acr);
163 
164 	clrbits_le32(&STM32_RCC->cfgr, (RCC_CFGR_SW0 | RCC_CFGR_SW1));
165 	setbits_le32(&STM32_RCC->cfgr, RCC_CFGR_SW_PLL);
166 
167 	while ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) !=
168 			RCC_CFGR_SWS_PLL)
169 		;
170 
171 	return 0;
172 }
173 
174 unsigned long clock_get(enum clock clck)
175 {
176 	u32 sysclk = 0;
177 	u32 shift = 0;
178 	/* Prescaler table lookups for clock computation */
179 	u8 ahb_psc_table[16] = {
180 		0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9
181 	};
182 	u8 apb_psc_table[8] = {
183 		0, 0, 0, 0, 1, 2, 3, 4
184 	};
185 
186 	if ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) ==
187 			RCC_CFGR_SWS_PLL) {
188 		u16 pllm, plln, pllp;
189 		pllm = (readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLM_MASK);
190 		plln = ((readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLN_MASK)
191 			>> RCC_PLLCFGR_PLLN_SHIFT);
192 		pllp = ((((readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLP_MASK)
193 			>> RCC_PLLCFGR_PLLP_SHIFT) + 1) << 1);
194 		sysclk = ((CONFIG_STM32_HSE_HZ / pllm) * plln) / pllp;
195 	}
196 
197 	switch (clck) {
198 	case CLOCK_CORE:
199 		return sysclk;
200 		break;
201 	case CLOCK_AHB:
202 		shift = ahb_psc_table[(
203 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_AHB_PSC_MASK)
204 			>> RCC_CFGR_HPRE_SHIFT)];
205 		return sysclk >>= shift;
206 		break;
207 	case CLOCK_APB1:
208 		shift = apb_psc_table[(
209 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_APB1_PSC_MASK)
210 			>> RCC_CFGR_PPRE1_SHIFT)];
211 		return sysclk >>= shift;
212 		break;
213 	case CLOCK_APB2:
214 		shift = apb_psc_table[(
215 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_APB2_PSC_MASK)
216 			>> RCC_CFGR_PPRE2_SHIFT)];
217 		return sysclk >>= shift;
218 		break;
219 	default:
220 		return 0;
221 		break;
222 	}
223 }
224