diff --git a/drivers/clk/clk_stm32f.c b/drivers/clk/clk_stm32f.c index 926b249ff3..bde31607cf 100644 --- a/drivers/clk/clk_stm32f.c +++ b/drivers/clk/clk_stm32f.c @@ -63,6 +63,7 @@ #define RCC_PLLSAICFGR_PLLSAIQ_4 BIT(26) #define RCC_PLLSAICFGR_PLLSAIR_2 BIT(29) +#define RCC_DCKCFGRX_TIMPRE BIT(24) #define RCC_DCKCFGRX_CK48MSEL BIT(27) #define RCC_DCKCFGRX_SDMMC1SEL BIT(28) #define RCC_DCKCFGR2_SDMMC2SEL BIT(29) @@ -260,21 +261,88 @@ static unsigned long stm32_clk_pll48clk_rate(struct stm32_clk *priv, return sysclk / pllq; } -static unsigned long stm32_clk_get_rate(struct clk *clk) +static bool stm32_get_timpre(struct stm32_clk *priv) { - struct stm32_clk *priv = dev_get_priv(clk->dev); struct stm32_rcc_regs *regs = priv->base; - u32 sysclk = 0; - u32 shift = 0; - u16 pllm, plln, pllp; + u32 val; + + if (priv->info.v2) /*stm32f7 case */ + val = readl(®s->dckcfgr2); + else + val = readl(®s->dckcfgr); + /* get timer prescaler */ + return !!(val & RCC_DCKCFGRX_TIMPRE); +} + +static u32 stm32_get_hclk_rate(struct stm32_rcc_regs *regs, u32 sysclk) +{ + u8 shift; /* 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 }; + + shift = ahb_psc_table[( + (readl(®s->cfgr) & RCC_CFGR_AHB_PSC_MASK) + >> RCC_CFGR_HPRE_SHIFT)]; + + return sysclk >> shift; +}; + +static u8 stm32_get_apb_shift(struct stm32_rcc_regs *regs, enum apb apb) +{ + /* Prescaler table lookups for clock computation */ u8 apb_psc_table[8] = { 0, 0, 0, 0, 1, 2, 3, 4 }; + if (apb == APB1) + return apb_psc_table[( + (readl(®s->cfgr) & RCC_CFGR_APB1_PSC_MASK) + >> RCC_CFGR_PPRE1_SHIFT)]; + else /* APB2 */ + return apb_psc_table[( + (readl(®s->cfgr) & RCC_CFGR_APB2_PSC_MASK) + >> RCC_CFGR_PPRE2_SHIFT)]; +}; + +static u32 stm32_get_timer_rate(struct stm32_clk *priv, u32 sysclk, + enum apb apb) +{ + struct stm32_rcc_regs *regs = priv->base; + u8 shift = stm32_get_apb_shift(regs, apb); + + if (stm32_get_timpre(priv)) + /* + * if APB prescaler is configured to a + * division factor of 1, 2 or 4 + */ + switch (shift) { + case 0: + case 1: + case 2: + return stm32_get_hclk_rate(regs, sysclk); + default: + return (sysclk >> shift) * 4; + } + else + /* + * if APB prescaler is configured to a + * division factor of 1 + */ + if (shift == 0) + return sysclk; + else + return (sysclk >> shift) * 2; +}; + +static ulong stm32_clk_get_rate(struct clk *clk) +{ + struct stm32_clk *priv = dev_get_priv(clk->dev); + struct stm32_rcc_regs *regs = priv->base; + u32 sysclk = 0; + u16 pllm, plln, pllp; + if ((readl(®s->cfgr) & RCC_CFGR_SWS_MASK) == RCC_CFGR_SWS_PLL) { pllm = (readl(®s->pllcfgr) & RCC_PLLCFGR_PLLM_MASK); @@ -293,16 +361,24 @@ static unsigned long stm32_clk_get_rate(struct clk *clk) * AHB1, AHB2 and AHB3 */ case STM32F7_AHB1_CLOCK(GPIOA) ... STM32F7_AHB3_CLOCK(QSPI): - shift = ahb_psc_table[( - (readl(®s->cfgr) & RCC_CFGR_AHB_PSC_MASK) - >> RCC_CFGR_HPRE_SHIFT)]; - return sysclk >>= shift; + return stm32_get_hclk_rate(regs, sysclk); /* APB1 CLOCK */ case STM32F7_APB1_CLOCK(TIM2) ... STM32F7_APB1_CLOCK(UART8): - shift = apb_psc_table[( - (readl(®s->cfgr) & RCC_CFGR_APB1_PSC_MASK) - >> RCC_CFGR_PPRE1_SHIFT)]; - return sysclk >>= shift; + /* For timer clock, an additionnal prescaler is used*/ + switch (clk->id) { + case STM32F7_APB1_CLOCK(TIM2): + case STM32F7_APB1_CLOCK(TIM3): + case STM32F7_APB1_CLOCK(TIM4): + case STM32F7_APB1_CLOCK(TIM5): + case STM32F7_APB1_CLOCK(TIM6): + case STM32F7_APB1_CLOCK(TIM7): + case STM32F7_APB1_CLOCK(TIM12): + case STM32F7_APB1_CLOCK(TIM13): + case STM32F7_APB1_CLOCK(TIM14): + return stm32_get_timer_rate(priv, sysclk, APB1); + } + return (sysclk >> stm32_get_apb_shift(regs, APB1)); + /* APB2 CLOCK */ case STM32F7_APB2_CLOCK(TIM1) ... STM32F7_APB2_CLOCK(LTDC): /* @@ -325,12 +401,18 @@ static unsigned long stm32_clk_get_rate(struct clk *clk) else return stm32_clk_pll48clk_rate(priv, sysclk); break; - } - shift = apb_psc_table[( - (readl(®s->cfgr) & RCC_CFGR_APB2_PSC_MASK) - >> RCC_CFGR_PPRE2_SHIFT)]; - return sysclk >>= shift; + /* For timer clock, an additionnal prescaler is used*/ + case STM32F7_APB2_CLOCK(TIM1): + case STM32F7_APB2_CLOCK(TIM8): + case STM32F7_APB2_CLOCK(TIM9): + case STM32F7_APB2_CLOCK(TIM10): + case STM32F7_APB2_CLOCK(TIM11): + return stm32_get_timer_rate(priv, sysclk, APB2); + break; + } + return (sysclk >> stm32_get_apb_shift(regs, APB2)); + default: pr_err("clock index %ld out of range\n", clk->id); return -EINVAL; diff --git a/include/stm32_rcc.h b/include/stm32_rcc.h index 063177bc98..484bc305f9 100644 --- a/include/stm32_rcc.h +++ b/include/stm32_rcc.h @@ -45,6 +45,11 @@ enum soc_family { STM32F7, }; +enum apb { + APB1, + APB2, +}; + struct stm32_rcc_clk { char *drv_name; enum soc_family soc;