u-boot/arch/avr32/cpu/at32ap700x/clk.c

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/*
* Copyright (C) 2005-2008 Atmel Corporation
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/clk.h>
#include <asm/arch/hardware.h>
#include <asm/arch/portmux.h>
#include "sm.h"
void clk_init(void)
{
uint32_t cksel;
/* in case of soft resets, disable watchdog */
sm_writel(WDT_CTRL, SM_BF(KEY, 0x55));
sm_writel(WDT_CTRL, SM_BF(KEY, 0xaa));
#ifdef CONFIG_PLL
/* Initialize the PLL */
sm_writel(PM_PLL0, (SM_BF(PLLCOUNT, CONFIG_SYS_PLL0_SUPPRESS_CYCLES)
| SM_BF(PLLMUL, CONFIG_SYS_PLL0_MUL - 1)
| SM_BF(PLLDIV, CONFIG_SYS_PLL0_DIV - 1)
| SM_BF(PLLOPT, CONFIG_SYS_PLL0_OPT)
| SM_BF(PLLOSC, 0)
| SM_BIT(PLLEN)));
/* Wait for lock */
while (!(sm_readl(PM_ISR) & SM_BIT(LOCK0))) ;
#endif
/* Set up clocks for the CPU and all peripheral buses */
cksel = 0;
if (CONFIG_SYS_CLKDIV_CPU)
cksel |= SM_BIT(CPUDIV) | SM_BF(CPUSEL, CONFIG_SYS_CLKDIV_CPU - 1);
if (CONFIG_SYS_CLKDIV_HSB)
cksel |= SM_BIT(HSBDIV) | SM_BF(HSBSEL, CONFIG_SYS_CLKDIV_HSB - 1);
if (CONFIG_SYS_CLKDIV_PBA)
cksel |= SM_BIT(PBADIV) | SM_BF(PBASEL, CONFIG_SYS_CLKDIV_PBA - 1);
if (CONFIG_SYS_CLKDIV_PBB)
cksel |= SM_BIT(PBBDIV) | SM_BF(PBBSEL, CONFIG_SYS_CLKDIV_PBB - 1);
sm_writel(PM_CKSEL, cksel);
#ifdef CONFIG_PLL
/* Use PLL0 as main clock */
sm_writel(PM_MCCTRL, SM_BIT(PLLSEL));
#ifdef CONFIG_LCD
/* Set up pixel clock for the LCDC */
sm_writel(PM_GCCTRL(7), SM_BIT(PLLSEL) | SM_BIT(CEN));
#endif
#endif
}
unsigned long __gclk_set_rate(unsigned int id, enum gclk_parent parent,
unsigned long rate, unsigned long parent_rate)
{
unsigned long divider;
if (rate == 0 || parent_rate == 0) {
sm_writel(PM_GCCTRL(id), 0);
return 0;
}
divider = (parent_rate + rate / 2) / rate;
if (divider <= 1) {
sm_writel(PM_GCCTRL(id), parent | SM_BIT(CEN));
rate = parent_rate;
} else {
divider = min(255UL, divider / 2 - 1);
sm_writel(PM_GCCTRL(id), parent | SM_BIT(CEN) | SM_BIT(DIVEN)
| SM_BF(DIV, divider));
rate = parent_rate / (2 * (divider + 1));
}
return rate;
}