u-boot/drivers/clk/clk_stm32f7.c
Patrice Chotard 1543bf794f clk: clk_stm32f7: fix PLL clock division factor
Fix clock division factor initialization for RCC_PLLCFGR
registers.

PLLR bits (bit 31-28) in RCC_PLLCFGR must not be cleared,
it's a forbidden value. So update RCC_PLLCFGR using
clrsetbits_le32() to set only necessary bits fields.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2017-11-17 07:44:13 -05:00

323 lines
8.3 KiB
C

/*
* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
* Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <asm/io.h>
#include <asm/arch/rcc.h>
#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)
#define RCC_CR_HSEBYP BIT(18)
#define RCC_CR_CSSON BIT(19)
#define RCC_CR_PLLON BIT(24)
#define RCC_CR_PLLRDY BIT(25)
#define RCC_PLLCFGR_PLLM_MASK GENMASK(5, 0)
#define RCC_PLLCFGR_PLLN_MASK GENMASK(14, 6)
#define RCC_PLLCFGR_PLLP_MASK GENMASK(17, 16)
#define RCC_PLLCFGR_PLLQ_MASK GENMASK(27, 24)
#define RCC_PLLCFGR_PLLSRC BIT(22)
#define RCC_PLLCFGR_PLLM_SHIFT 0
#define RCC_PLLCFGR_PLLN_SHIFT 6
#define RCC_PLLCFGR_PLLP_SHIFT 16
#define RCC_PLLCFGR_PLLQ_SHIFT 24
#define RCC_CFGR_AHB_PSC_MASK GENMASK(7, 4)
#define RCC_CFGR_APB1_PSC_MASK GENMASK(12, 10)
#define RCC_CFGR_APB2_PSC_MASK GENMASK(15, 13)
#define RCC_CFGR_SW0 BIT(0)
#define RCC_CFGR_SW1 BIT(1)
#define RCC_CFGR_SW_MASK GENMASK(1, 0)
#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 BIT(2)
#define RCC_CFGR_SWS1 BIT(3)
#define RCC_CFGR_SWS_MASK GENMASK(3, 2)
#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 10
#define RCC_CFGR_PPRE2_SHIFT 13
/*
* Offsets of some PWR registers
*/
#define PWR_CR1_ODEN BIT(16)
#define PWR_CR1_ODSWEN BIT(17)
#define PWR_CSR1_ODRDY BIT(16)
#define PWR_CSR1_ODSWRDY BIT(17)
struct pll_psc {
u8 pll_m;
u16 pll_n;
u8 pll_p;
u8 pll_q;
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
struct stm32_clk {
struct stm32_rcc_regs *base;
};
#if !defined(CONFIG_STM32_HSE_HZ)
#error "CONFIG_STM32_HSE_HZ not defined!"
#else
#if (CONFIG_STM32_HSE_HZ == 25000000)
#if (CONFIG_SYS_CLK_FREQ == 200000000)
/* 200 MHz */
struct pll_psc sys_pll_psc = {
.pll_m = 25,
.pll_n = 400,
.pll_p = 2,
.pll_q = 8,
.ahb_psc = AHB_PSC_1,
.apb1_psc = APB_PSC_4,
.apb2_psc = APB_PSC_2
};
#endif
#else
#error "No PLL/Prescaler configuration for given CONFIG_STM32_HSE_HZ exists"
#endif
#endif
static int configure_clocks(struct udevice *dev)
{
struct stm32_clk *priv = dev_get_priv(dev);
struct stm32_rcc_regs *regs = priv->base;
/* Reset RCC configuration */
setbits_le32(&regs->cr, RCC_CR_HSION);
writel(0, &regs->cfgr); /* Reset CFGR */
clrbits_le32(&regs->cr, (RCC_CR_HSEON | RCC_CR_CSSON
| RCC_CR_PLLON));
writel(0x24003010, &regs->pllcfgr); /* Reset value from RM */
clrbits_le32(&regs->cr, RCC_CR_HSEBYP);
writel(0, &regs->cir); /* Disable all interrupts */
/* Configure for HSE+PLL operation */
setbits_le32(&regs->cr, RCC_CR_HSEON);
while (!(readl(&regs->cr) & RCC_CR_HSERDY))
;
setbits_le32(&regs->cfgr, ((
sys_pll_psc.ahb_psc << RCC_CFGR_HPRE_SHIFT)
| (sys_pll_psc.apb1_psc << RCC_CFGR_PPRE1_SHIFT)
| (sys_pll_psc.apb2_psc << RCC_CFGR_PPRE2_SHIFT)));
/* Configure the main PLL */
setbits_le32(&regs->pllcfgr, RCC_PLLCFGR_PLLSRC); /* pll source HSE */
clrsetbits_le32(&regs->pllcfgr, RCC_PLLCFGR_PLLM_MASK,
sys_pll_psc.pll_m << RCC_PLLCFGR_PLLM_SHIFT);
clrsetbits_le32(&regs->pllcfgr, RCC_PLLCFGR_PLLN_MASK,
sys_pll_psc.pll_n << RCC_PLLCFGR_PLLN_SHIFT);
clrsetbits_le32(&regs->pllcfgr, RCC_PLLCFGR_PLLP_MASK,
((sys_pll_psc.pll_p >> 1) - 1) << RCC_PLLCFGR_PLLP_SHIFT);
clrsetbits_le32(&regs->pllcfgr, RCC_PLLCFGR_PLLQ_MASK,
sys_pll_psc.pll_q << RCC_PLLCFGR_PLLQ_SHIFT);
/* Enable the main PLL */
setbits_le32(&regs->cr, RCC_CR_PLLON);
while (!(readl(&regs->cr) & RCC_CR_PLLRDY))
;
/* Enable high performance mode, System frequency up to 200 MHz */
setbits_le32(&regs->apb1enr, RCC_APB1ENR_PWREN);
setbits_le32(&STM32_PWR->cr1, PWR_CR1_ODEN);
/* Infinite wait! */
while (!(readl(&STM32_PWR->csr1) & PWR_CSR1_ODRDY))
;
/* Enable the Over-drive switch */
setbits_le32(&STM32_PWR->cr1, PWR_CR1_ODSWEN);
/* Infinite wait! */
while (!(readl(&STM32_PWR->csr1) & PWR_CSR1_ODSWRDY))
;
stm32_flash_latency_cfg(5);
clrbits_le32(&regs->cfgr, (RCC_CFGR_SW0 | RCC_CFGR_SW1));
setbits_le32(&regs->cfgr, RCC_CFGR_SW_PLL);
while ((readl(&regs->cfgr) & RCC_CFGR_SWS_MASK) !=
RCC_CFGR_SWS_PLL)
;
return 0;
}
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:
pr_err("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);
struct stm32_rcc_regs *regs = priv->base;
u32 offset = clk->id / 32;
u32 bit_index = clk->id % 32;
debug("%s: clkid = %ld, offset from AHB1ENR is %d, bit_index = %d\n",
__func__, clk->id, offset, bit_index);
setbits_le32(&regs->ahb1enr + offset, BIT(bit_index));
return 0;
}
void clock_setup(int peripheral)
{
switch (peripheral) {
case SYSCFG_CLOCK_CFG:
setbits_le32(&STM32_RCC->apb2enr, RCC_APB2ENR_SYSCFGEN);
break;
case TIMER2_CLOCK_CFG:
setbits_le32(&STM32_RCC->apb1enr, RCC_APB1ENR_TIM2EN);
break;
case STMMAC_CLOCK_CFG:
setbits_le32(&STM32_RCC->ahb1enr, RCC_AHB1ENR_ETHMAC_EN);
setbits_le32(&STM32_RCC->ahb1enr, RCC_AHB1ENR_ETHMAC_RX_EN);
setbits_le32(&STM32_RCC->ahb1enr, RCC_AHB1ENR_ETHMAC_TX_EN);
break;
default:
break;
}
}
static int stm32_clk_probe(struct udevice *dev)
{
debug("%s: stm32_clk_probe\n", __func__);
struct stm32_clk *priv = dev_get_priv(dev);
fdt_addr_t addr;
addr = devfdt_get_addr(dev);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
priv->base = (struct stm32_rcc_regs *)addr;
configure_clocks(dev);
return 0;
}
static int stm32_clk_of_xlate(struct clk *clk, struct ofnode_phandle_args *args)
{
debug("%s(clk=%p)\n", __func__, clk);
if (args->args_count != 2) {
debug("Invaild args_count: %d\n", args->args_count);
return -EINVAL;
}
if (args->args_count)
clk->id = args->args[1];
else
clk->id = 0;
return 0;
}
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[] = {
{ .compatible = "st,stm32f42xx-rcc"},
{}
};
U_BOOT_DRIVER(stm32f7_clk) = {
.name = "stm32f7_clk",
.id = UCLASS_CLK,
.of_match = stm32_clk_ids,
.ops = &stm32_clk_ops,
.probe = stm32_clk_probe,
.priv_auto_alloc_size = sizeof(struct stm32_clk),
.flags = DM_FLAG_PRE_RELOC,
};