clk: stm32f7: add clock .get_rate() callback

Add clock framework .get_rate callback.
This step will allow to convert all drivers which was using
proprietary clock_get() to use clock framework .get_rate().

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Vikas MANOCHA <vikas.manocha@st.com>

diff --git a/arch/arm/include/asm/arch-stm32f7/rcc.h b/arch/arm/include/asm/arch-stm32f7/rcc.h
index 0f8d50b4c6140a11a3313bb2cd4f203166ef09c0..cc9b57f803f2b3664570efef15efe89d8a72053e 100644 (file)
--- a/arch/arm/include/asm/arch-stm32f7/rcc.h
+++ b/arch/arm/include/asm/arch-stm32f7/rcc.h
@@ -8,6 +8,8 @@
 #ifndef _STM32_RCC_H
 #define _STM32_RCC_H
 
+#include <dt-bindings/mfd/stm32f7-rcc.h>
+
 /*
  * RCC AHB1ENR specific definitions
  */

diff --git a/drivers/clk/clk_stm32f7.c b/drivers/clk/clk_stm32f7.c
index 7dd91b6a58572eff712d25fe55f66f500c6b58ec..5e20b0cbb79512bd90d5f6bce7534904e165239f 100644 (file)
--- a/drivers/clk/clk_stm32f7.c
+++ b/drivers/clk/clk_stm32f7.c
@@ -12,6 +12,8 @@
 #include <asm/arch/stm32.h>
 #include <asm/arch/stm32_periph.h>
 
+#include <dt-bindings/mfd/stm32f7-rcc.h>
+
 #define RCC_CR_HSION                   BIT(0)
 #define RCC_CR_HSEON                   BIT(16)
 #define RCC_CR_HSERDY                  BIT(17)
@@ -220,6 +222,65 @@ unsigned long clock_get(enum clock clck)
        }
 }
 
+static unsigned long 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;
+       u32 shift = 0;
+       /* 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(&regs->cfgr) & RCC_CFGR_SWS_MASK) ==
+                       RCC_CFGR_SWS_PLL) {
+               u16 pllm, plln, pllp;
+               pllm = (readl(&regs->pllcfgr) & RCC_PLLCFGR_PLLM_MASK);
+               plln = ((readl(&regs->pllcfgr) & RCC_PLLCFGR_PLLN_MASK)
+                       >> RCC_PLLCFGR_PLLN_SHIFT);
+               pllp = ((((readl(&regs->pllcfgr) & RCC_PLLCFGR_PLLP_MASK)
+                       >> RCC_PLLCFGR_PLLP_SHIFT) + 1) << 1);
+               sysclk = ((CONFIG_STM32_HSE_HZ / pllm) * plln) / pllp;
+       } else {
+               return -EINVAL;
+       }
+
+       switch (clk->id) {
+       /*
+        * AHB CLOCK: 3 x 32 bits consecutive registers are used :
+        * AHB1, AHB2 and AHB3
+        */
+       case STM32F7_AHB1_CLOCK(GPIOA) ... STM32F7_AHB3_CLOCK(QSPI):
+               shift = ahb_psc_table[(
+                       (readl(&regs->cfgr) & RCC_CFGR_AHB_PSC_MASK)
+                       >> RCC_CFGR_HPRE_SHIFT)];
+               return sysclk >>= shift;
+               break;
+       /* APB1 CLOCK */
+       case STM32F7_APB1_CLOCK(TIM2) ... STM32F7_APB1_CLOCK(UART8):
+               shift = apb_psc_table[(
+                       (readl(&regs->cfgr) & RCC_CFGR_APB1_PSC_MASK)
+                       >> RCC_CFGR_PPRE1_SHIFT)];
+               return sysclk >>= shift;
+               break;
+       /* APB2 CLOCK */
+       case STM32F7_APB2_CLOCK(TIM1) ... STM32F7_APB2_CLOCK(LTDC):
+               shift = apb_psc_table[(
+                       (readl(&regs->cfgr) & RCC_CFGR_APB2_PSC_MASK)
+                       >> RCC_CFGR_PPRE2_SHIFT)];
+               return sysclk >>= shift;
+               break;
+       default:
+               error("clock index %ld out of range\n", clk->id);
+               return -EINVAL;
+               break;
+       }
+}
+
 static int stm32_clk_enable(struct clk *clk)
 {
        struct stm32_clk *priv = dev_get_priv(clk->dev);
@@ -291,6 +352,7 @@ static int stm32_clk_of_xlate(struct clk *clk, struct ofnode_phandle_args *args)
 static struct clk_ops stm32_clk_ops = {
        .of_xlate       = stm32_clk_of_xlate,
        .enable         = stm32_clk_enable,
+       .get_rate       = stm32_clk_get_rate,
 };
 
 static const struct udevice_id stm32_clk_ids[] = {