diff options
Diffstat (limited to 'arch/arm/mach-stm32/stm32f1/clock.c')
-rw-r--r-- | arch/arm/mach-stm32/stm32f1/clock.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/arch/arm/mach-stm32/stm32f1/clock.c b/arch/arm/mach-stm32/stm32f1/clock.c new file mode 100644 index 0000000..2820848 --- /dev/null +++ b/arch/arm/mach-stm32/stm32f1/clock.c @@ -0,0 +1,196 @@ +/* + * (C) Copyright 2015 + * Kamil Lulko, <kamil.lulko@gmail.com> + * + * Copyright 2015 ATS Advanced Telematics Systems GmbH + * Copyright 2015 Konsulko Group, Matt Porter <mporter@konsulko.com> + * + * (C) Copyright 2014 + * STMicroelectronics + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/arch/stm32.h> + +#define RCC_CR_HSION (1 << 0) +#define RCC_CR_HSEON (1 << 16) +#define RCC_CR_HSERDY (1 << 17) +#define RCC_CR_HSEBYP (1 << 18) +#define RCC_CR_CSSON (1 << 19) +#define RCC_CR_PLLON (1 << 24) +#define RCC_CR_PLLRDY (1 << 25) + +#define RCC_CFGR_PLLMUL_MASK 0x3C0000 +#define RCC_CFGR_PLLMUL_SHIFT 18 +#define RCC_CFGR_PLLSRC_HSE (1 << 16) + +#define RCC_CFGR_AHB_PSC_MASK 0xF0 +#define RCC_CFGR_APB1_PSC_MASK 0x700 +#define RCC_CFGR_APB2_PSC_MASK 0x3800 +#define RCC_CFGR_SW0 (1 << 0) +#define RCC_CFGR_SW1 (1 << 1) +#define RCC_CFGR_SW_MASK 0x3 +#define RCC_CFGR_SW_HSI 0 +#define RCC_CFGR_SW_HSE RCC_CFGR_SW0 +#define RCC_CFGR_SW_PLL RCC_CFGR_SW1 +#define RCC_CFGR_SWS0 (1 << 2) +#define RCC_CFGR_SWS1 (1 << 3) +#define RCC_CFGR_SWS_MASK 0xC +#define RCC_CFGR_SWS_HSI 0 +#define RCC_CFGR_SWS_HSE RCC_CFGR_SWS0 +#define RCC_CFGR_SWS_PLL RCC_CFGR_SWS1 +#define RCC_CFGR_HPRE_SHIFT 4 +#define RCC_CFGR_PPRE1_SHIFT 8 +#define RCC_CFGR_PPRE2_SHIFT 11 + +#define RCC_APB1ENR_PWREN (1 << 28) + +#define PWR_CR_VOS0 (1 << 14) +#define PWR_CR_VOS1 (1 << 15) +#define PWR_CR_VOS_MASK 0xC000 +#define PWR_CR_VOS_SCALE_MODE_1 (PWR_CR_VOS0 | PWR_CR_VOS1) +#define PWR_CR_VOS_SCALE_MODE_2 (PWR_CR_VOS1) +#define PWR_CR_VOS_SCALE_MODE_3 (PWR_CR_VOS0) + +#define FLASH_ACR_WS(n) n +#define FLASH_ACR_PRFTEN (1 << 8) +#define FLASH_ACR_ICEN (1 << 9) +#define FLASH_ACR_DCEN (1 << 10) + +struct psc { + u8 ahb_psc; + u8 apb1_psc; + u8 apb2_psc; +}; + +#define AHB_PSC_1 0 +#define AHB_PSC_2 0x8 +#define AHB_PSC_4 0x9 +#define AHB_PSC_8 0xA +#define AHB_PSC_16 0xB +#define AHB_PSC_64 0xC +#define AHB_PSC_128 0xD +#define AHB_PSC_256 0xE +#define AHB_PSC_512 0xF + +#define APB_PSC_1 0 +#define APB_PSC_2 0x4 +#define APB_PSC_4 0x5 +#define APB_PSC_8 0x6 +#define APB_PSC_16 0x7 + +#if !defined(CONFIG_STM32_HSE_HZ) +#error "CONFIG_STM32_HSE_HZ not defined!" +#else +#if (CONFIG_STM32_HSE_HZ == 8000000) +#define RCC_CFGR_PLLMUL_CFG 0x7 +struct psc psc_hse = { + .ahb_psc = AHB_PSC_1, + .apb1_psc = APB_PSC_2, + .apb2_psc = APB_PSC_1 +}; +#else +#error "No PLL/Prescaler configuration for given CONFIG_STM32_HSE_HZ exists" +#endif +#endif + +int configure_clocks(void) +{ + /* Reset RCC configuration */ + setbits_le32(&STM32_RCC->cr, RCC_CR_HSION); + writel(0, &STM32_RCC->cfgr); /* Reset CFGR */ + clrbits_le32(&STM32_RCC->cr, (RCC_CR_HSEON | RCC_CR_CSSON + | RCC_CR_PLLON)); + clrbits_le32(&STM32_RCC->cr, RCC_CR_HSEBYP); + writel(0, &STM32_RCC->cir); /* Disable all interrupts */ + + /* Configure for HSE+PLL operation */ + setbits_le32(&STM32_RCC->cr, RCC_CR_HSEON); + while (!(readl(&STM32_RCC->cr) & RCC_CR_HSERDY)) + ; + + /* Enable high performance mode, System frequency up to 168 MHz */ + setbits_le32(&STM32_RCC->apb1enr, RCC_APB1ENR_PWREN); + writel(PWR_CR_VOS_SCALE_MODE_1, &STM32_PWR->cr); + + setbits_le32(&STM32_RCC->cfgr, + RCC_CFGR_PLLMUL_CFG << RCC_CFGR_PLLMUL_SHIFT); + setbits_le32(&STM32_RCC->cfgr, RCC_CFGR_PLLSRC_HSE); + setbits_le32(&STM32_RCC->cfgr, (( + psc_hse.ahb_psc << RCC_CFGR_HPRE_SHIFT) + | (psc_hse.apb1_psc << RCC_CFGR_PPRE1_SHIFT) + | (psc_hse.apb2_psc << RCC_CFGR_PPRE2_SHIFT))); + + setbits_le32(&STM32_RCC->cr, RCC_CR_PLLON); + + while (!(readl(&STM32_RCC->cr) & RCC_CR_PLLRDY)) + ; + + /* 5 wait states, Prefetch enabled, D-Cache enabled, I-Cache enabled */ + writel(FLASH_ACR_WS(5) | FLASH_ACR_PRFTEN | FLASH_ACR_ICEN + | FLASH_ACR_DCEN, &STM32_FLASH->acr); + + clrbits_le32(&STM32_RCC->cfgr, (RCC_CFGR_SW0 | RCC_CFGR_SW1)); + setbits_le32(&STM32_RCC->cfgr, RCC_CFGR_SW_PLL); + + while ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) != + RCC_CFGR_SWS_PLL) + ; + + return 0; +} + +unsigned long clock_get(enum clock clck) +{ + u32 sysclk = 0; + u32 shift = 0; + /* PLL table lookups for clock computation */ + u8 pll_mul_table[16] = { + 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 16 + }; + /* Prescaler table lookups for clock computation */ + u8 ahb_psc_table[16] = { + 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9 + }; + u8 apb_psc_table[8] = { + 0, 0, 0, 0, 1, 2, 3, 4 + }; + + if ((readl(&STM32_RCC->cfgr) & RCC_CFGR_SWS_MASK) == + RCC_CFGR_SWS_PLL) { + u16 pll; + pll = ((readl(&STM32_RCC->cfgr) & RCC_CFGR_PLLMUL_MASK) + >> RCC_CFGR_PLLMUL_SHIFT); + sysclk = CONFIG_STM32_HSE_HZ * pll_mul_table[pll]; + } + + switch (clck) { + case CLOCK_CORE: + return sysclk; + break; + case CLOCK_AHB: + shift = ahb_psc_table[( + (readl(&STM32_RCC->cfgr) & RCC_CFGR_AHB_PSC_MASK) + >> RCC_CFGR_HPRE_SHIFT)]; + return sysclk >>= shift; + break; + case CLOCK_APB1: + shift = apb_psc_table[( + (readl(&STM32_RCC->cfgr) & RCC_CFGR_APB1_PSC_MASK) + >> RCC_CFGR_PPRE1_SHIFT)]; + return sysclk >>= shift; + break; + case CLOCK_APB2: + shift = apb_psc_table[( + (readl(&STM32_RCC->cfgr) & RCC_CFGR_APB2_PSC_MASK) + >> RCC_CFGR_PPRE2_SHIFT)]; + return sysclk >>= shift; + break; + default: + return 0; + break; + } +} |