xref: /rk3399_rockchip-uboot/arch/arm/mach-stm32/stm32f4/clock.c (revision 03a3a8aec85780f034c9c8fca4a12abfeb9b4da7)
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 #include <asm/arch/stm32_periph.h>
15 
16 #define RCC_CR_HSION		(1 << 0)
17 #define RCC_CR_HSEON		(1 << 16)
18 #define RCC_CR_HSERDY		(1 << 17)
19 #define RCC_CR_HSEBYP		(1 << 18)
20 #define RCC_CR_CSSON		(1 << 19)
21 #define RCC_CR_PLLON		(1 << 24)
22 #define RCC_CR_PLLRDY		(1 << 25)
23 
24 #define RCC_PLLCFGR_PLLM_MASK	0x3F
25 #define RCC_PLLCFGR_PLLN_MASK	0x7FC0
26 #define RCC_PLLCFGR_PLLP_MASK	0x30000
27 #define RCC_PLLCFGR_PLLQ_MASK	0xF000000
28 #define RCC_PLLCFGR_PLLSRC	(1 << 22)
29 #define RCC_PLLCFGR_PLLN_SHIFT	6
30 #define RCC_PLLCFGR_PLLP_SHIFT	16
31 #define RCC_PLLCFGR_PLLQ_SHIFT	24
32 
33 #define RCC_CFGR_AHB_PSC_MASK	0xF0
34 #define RCC_CFGR_APB1_PSC_MASK	0x1C00
35 #define RCC_CFGR_APB2_PSC_MASK	0xE000
36 #define RCC_CFGR_SW0		(1 << 0)
37 #define RCC_CFGR_SW1		(1 << 1)
38 #define RCC_CFGR_SW_MASK	0x3
39 #define RCC_CFGR_SW_HSI		0
40 #define RCC_CFGR_SW_HSE		RCC_CFGR_SW0
41 #define RCC_CFGR_SW_PLL		RCC_CFGR_SW1
42 #define RCC_CFGR_SWS0		(1 << 2)
43 #define RCC_CFGR_SWS1		(1 << 3)
44 #define RCC_CFGR_SWS_MASK	0xC
45 #define RCC_CFGR_SWS_HSI	0
46 #define RCC_CFGR_SWS_HSE	RCC_CFGR_SWS0
47 #define RCC_CFGR_SWS_PLL	RCC_CFGR_SWS1
48 #define RCC_CFGR_HPRE_SHIFT	4
49 #define RCC_CFGR_PPRE1_SHIFT	10
50 #define RCC_CFGR_PPRE2_SHIFT	13
51 
52 #define RCC_APB1ENR_PWREN	(1 << 28)
53 
54 /*
55  * RCC USART specific definitions
56  */
57 #define RCC_ENR_USART1EN		(1 << 4)
58 #define RCC_ENR_USART2EN		(1 << 17)
59 #define RCC_ENR_USART3EN		(1 << 18)
60 #define RCC_ENR_USART6EN		(1 <<  5)
61 
62 #define PWR_CR_VOS0		(1 << 14)
63 #define PWR_CR_VOS1		(1 << 15)
64 #define PWR_CR_VOS_MASK		0xC000
65 #define PWR_CR_VOS_SCALE_MODE_1	(PWR_CR_VOS0 | PWR_CR_VOS1)
66 #define PWR_CR_VOS_SCALE_MODE_2	(PWR_CR_VOS1)
67 #define PWR_CR_VOS_SCALE_MODE_3	(PWR_CR_VOS0)
68 
69 #define FLASH_ACR_WS(n)		n
70 #define FLASH_ACR_PRFTEN	(1 << 8)
71 #define FLASH_ACR_ICEN		(1 << 9)
72 #define FLASH_ACR_DCEN		(1 << 10)
73 
74 struct pll_psc {
75 	u8	pll_m;
76 	u16	pll_n;
77 	u8	pll_p;
78 	u8	pll_q;
79 	u8	ahb_psc;
80 	u8	apb1_psc;
81 	u8	apb2_psc;
82 };
83 
84 #define AHB_PSC_1		0
85 #define AHB_PSC_2		0x8
86 #define AHB_PSC_4		0x9
87 #define AHB_PSC_8		0xA
88 #define AHB_PSC_16		0xB
89 #define AHB_PSC_64		0xC
90 #define AHB_PSC_128		0xD
91 #define AHB_PSC_256		0xE
92 #define AHB_PSC_512		0xF
93 
94 #define APB_PSC_1		0
95 #define APB_PSC_2		0x4
96 #define APB_PSC_4		0x5
97 #define APB_PSC_8		0x6
98 #define APB_PSC_16		0x7
99 
100 #if !defined(CONFIG_STM32_HSE_HZ)
101 #error "CONFIG_STM32_HSE_HZ not defined!"
102 #else
103 #if (CONFIG_STM32_HSE_HZ == 8000000)
104 #if (CONFIG_SYS_CLK_FREQ == 180000000)
105 /* 180 MHz */
106 struct pll_psc sys_pll_psc = {
107 	.pll_m = 8,
108 	.pll_n = 360,
109 	.pll_p = 2,
110 	.pll_q = 8,
111 	.ahb_psc = AHB_PSC_1,
112 	.apb1_psc = APB_PSC_4,
113 	.apb2_psc = APB_PSC_2
114 };
115 #else
116 /* default 168 MHz */
117 struct pll_psc sys_pll_psc = {
118 	.pll_m = 8,
119 	.pll_n = 336,
120 	.pll_p = 2,
121 	.pll_q = 7,
122 	.ahb_psc = AHB_PSC_1,
123 	.apb1_psc = APB_PSC_4,
124 	.apb2_psc = APB_PSC_2
125 };
126 #endif
127 #else
128 #error "No PLL/Prescaler configuration for given CONFIG_STM32_HSE_HZ exists"
129 #endif
130 #endif
131 
132 int configure_clocks(void)
133 {
134 	/* Reset RCC configuration */
135 	setbits_le32(&STM32_RCC->cr, RCC_CR_HSION);
136 	writel(0, &STM32_RCC->cfgr); /* Reset CFGR */
137 	clrbits_le32(&STM32_RCC->cr, (RCC_CR_HSEON | RCC_CR_CSSON
138 		| RCC_CR_PLLON));
139 	writel(0x24003010, &STM32_RCC->pllcfgr); /* Reset value from RM */
140 	clrbits_le32(&STM32_RCC->cr, RCC_CR_HSEBYP);
141 	writel(0, &STM32_RCC->cir); /* Disable all interrupts */
142 
143 	/* Configure for HSE+PLL operation */
144 	setbits_le32(&STM32_RCC->cr, RCC_CR_HSEON);
145 	while (!(readl(&STM32_RCC->cr) & RCC_CR_HSERDY))
146 		;
147 
148 	/* Enable high performance mode, System frequency up to 180 MHz */
149 	setbits_le32(&STM32_RCC->apb1enr, RCC_APB1ENR_PWREN);
150 	writel(PWR_CR_VOS_SCALE_MODE_1, &STM32_PWR->cr);
151 
152 	setbits_le32(&STM32_RCC->cfgr, ((
153 		sys_pll_psc.ahb_psc << RCC_CFGR_HPRE_SHIFT)
154 		| (sys_pll_psc.apb1_psc << RCC_CFGR_PPRE1_SHIFT)
155 		| (sys_pll_psc.apb2_psc << RCC_CFGR_PPRE2_SHIFT)));
156 
157 	writel(sys_pll_psc.pll_m
158 		| (sys_pll_psc.pll_n << RCC_PLLCFGR_PLLN_SHIFT)
159 		| (((sys_pll_psc.pll_p >> 1) - 1) << RCC_PLLCFGR_PLLP_SHIFT)
160 		| (sys_pll_psc.pll_q << RCC_PLLCFGR_PLLQ_SHIFT),
161 		&STM32_RCC->pllcfgr);
162 	setbits_le32(&STM32_RCC->pllcfgr, RCC_PLLCFGR_PLLSRC);
163 
164 	setbits_le32(&STM32_RCC->cr, RCC_CR_PLLON);
165 
166 	while (!(readl(&STM32_RCC->cr) & RCC_CR_PLLRDY))
167 		;
168 
169 	/* 5 wait states, Prefetch enabled, D-Cache enabled, I-Cache enabled */
170 	writel(FLASH_ACR_WS(5) | FLASH_ACR_PRFTEN | FLASH_ACR_ICEN
171 		| FLASH_ACR_DCEN, &STM32_FLASH->acr);
172 
173 	clrbits_le32(&STM32_RCC->cfgr, (RCC_CFGR_SW0 | RCC_CFGR_SW1));
174 	setbits_le32(&STM32_RCC->cfgr, RCC_CFGR_SW_PLL);
175 
176 	while ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) !=
177 			RCC_CFGR_SWS_PLL)
178 		;
179 
180 	return 0;
181 }
182 
183 unsigned long clock_get(enum clock clck)
184 {
185 	u32 sysclk = 0;
186 	u32 shift = 0;
187 	/* Prescaler table lookups for clock computation */
188 	u8 ahb_psc_table[16] = {
189 		0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9
190 	};
191 	u8 apb_psc_table[8] = {
192 		0, 0, 0, 0, 1, 2, 3, 4
193 	};
194 
195 	if ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) ==
196 			RCC_CFGR_SWS_PLL) {
197 		u16 pllm, plln, pllp;
198 		pllm = (readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLM_MASK);
199 		plln = ((readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLN_MASK)
200 			>> RCC_PLLCFGR_PLLN_SHIFT);
201 		pllp = ((((readl(&STM32_RCC->pllcfgr) & RCC_PLLCFGR_PLLP_MASK)
202 			>> RCC_PLLCFGR_PLLP_SHIFT) + 1) << 1);
203 		sysclk = ((CONFIG_STM32_HSE_HZ / pllm) * plln) / pllp;
204 	}
205 
206 	switch (clck) {
207 	case CLOCK_CORE:
208 		return sysclk;
209 		break;
210 	case CLOCK_AHB:
211 		shift = ahb_psc_table[(
212 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_AHB_PSC_MASK)
213 			>> RCC_CFGR_HPRE_SHIFT)];
214 		return sysclk >>= shift;
215 		break;
216 	case CLOCK_APB1:
217 		shift = apb_psc_table[(
218 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_APB1_PSC_MASK)
219 			>> RCC_CFGR_PPRE1_SHIFT)];
220 		return sysclk >>= shift;
221 		break;
222 	case CLOCK_APB2:
223 		shift = apb_psc_table[(
224 			(readl(&STM32_RCC->cfgr) & RCC_CFGR_APB2_PSC_MASK)
225 			>> RCC_CFGR_PPRE2_SHIFT)];
226 		return sysclk >>= shift;
227 		break;
228 	default:
229 		return 0;
230 		break;
231 	}
232 }
233 
234 void clock_setup(int peripheral)
235 {
236 	switch (peripheral) {
237 	case USART1_CLOCK_CFG:
238 		setbits_le32(&STM32_RCC->apb2enr, RCC_ENR_USART1EN);
239 		break;
240 	default:
241 		break;
242 	}
243 }
244