u-boot/arch/arm/cpu/armv7/am33xx/clock.c
Vaibhav Hiremath 000820b583 am335x: Enable RTC 32K OSC clock
In order to support low power state, you must source kernel system
timers to persistent clock, available across suspend/resume.  In case of
AM335x device, the only source we have is, RTC32K, available in
wakeup/always-on domain.  Having said that, during validation it has
been observed that, RTC clock need couple of seconds delay to stabilize
the RTC OSC clock; and such a huge delay is not acceptable in kernel
especially during early init and also it will impact quick/fast boot
use-cases.

So, RTC32k OSC enable dependency has been shifted to
SPL/first-bootloader.

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Tom Rini <trini@ti.com>
2012-10-25 11:30:22 -07:00

321 lines
8.2 KiB
C

/*
* clock.c
*
* clocks for AM33XX based boards
*
* Copyright (C) 2011, Texas Instruments, Incorporated - http://www.ti.com/
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR /PURPOSE. See the
* GNU General Public License for more details.
*/
#include <common.h>
#include <asm/arch/cpu.h>
#include <asm/arch/clock.h>
#include <asm/arch/hardware.h>
#include <asm/io.h>
#define PRCM_MOD_EN 0x2
#define PRCM_FORCE_WAKEUP 0x2
#define PRCM_FUNCTL 0x0
#define PRCM_EMIF_CLK_ACTIVITY BIT(2)
#define PRCM_L3_GCLK_ACTIVITY BIT(4)
#define PLL_BYPASS_MODE 0x4
#define ST_MN_BYPASS 0x00000100
#define ST_DPLL_CLK 0x00000001
#define CLK_SEL_MASK 0x7ffff
#define CLK_DIV_MASK 0x1f
#define CLK_DIV2_MASK 0x7f
#define CLK_SEL_SHIFT 0x8
#define CLK_MODE_SEL 0x7
#define CLK_MODE_MASK 0xfffffff8
#define CLK_DIV_SEL 0xFFFFFFE0
#define CPGMAC0_IDLE 0x30000
const struct cm_perpll *cmper = (struct cm_perpll *)CM_PER;
const struct cm_wkuppll *cmwkup = (struct cm_wkuppll *)CM_WKUP;
const struct cm_dpll *cmdpll = (struct cm_dpll *)CM_DPLL;
const struct cm_rtc *cmrtc = (struct cm_rtc *)CM_RTC;
static void enable_interface_clocks(void)
{
/* Enable all the Interconnect Modules */
writel(PRCM_MOD_EN, &cmper->l3clkctrl);
while (readl(&cmper->l3clkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmper->l4lsclkctrl);
while (readl(&cmper->l4lsclkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmper->l4fwclkctrl);
while (readl(&cmper->l4fwclkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmwkup->wkl4wkclkctrl);
while (readl(&cmwkup->wkl4wkclkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmper->l3instrclkctrl);
while (readl(&cmper->l3instrclkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmper->l4hsclkctrl);
while (readl(&cmper->l4hsclkctrl) != PRCM_MOD_EN)
;
writel(PRCM_MOD_EN, &cmwkup->wkgpio0clkctrl);
while (readl(&cmwkup->wkgpio0clkctrl) != PRCM_MOD_EN)
;
}
/*
* Force power domain wake up transition
* Ensure that the corresponding interface clock is active before
* using the peripheral
*/
static void power_domain_wkup_transition(void)
{
writel(PRCM_FORCE_WAKEUP, &cmper->l3clkstctrl);
writel(PRCM_FORCE_WAKEUP, &cmper->l4lsclkstctrl);
writel(PRCM_FORCE_WAKEUP, &cmwkup->wkclkstctrl);
writel(PRCM_FORCE_WAKEUP, &cmper->l4fwclkstctrl);
writel(PRCM_FORCE_WAKEUP, &cmper->l3sclkstctrl);
}
/*
* Enable the peripheral clock for required peripherals
*/
static void enable_per_clocks(void)
{
/* Enable the control module though RBL would have done it*/
writel(PRCM_MOD_EN, &cmwkup->wkctrlclkctrl);
while (readl(&cmwkup->wkctrlclkctrl) != PRCM_MOD_EN)
;
/* Enable the module clock */
writel(PRCM_MOD_EN, &cmper->timer2clkctrl);
while (readl(&cmper->timer2clkctrl) != PRCM_MOD_EN)
;
/* Select the Master osc 24 MHZ as Timer2 clock source */
writel(0x1, &cmdpll->clktimer2clk);
/* UART0 */
writel(PRCM_MOD_EN, &cmwkup->wkup_uart0ctrl);
while (readl(&cmwkup->wkup_uart0ctrl) != PRCM_MOD_EN)
;
/* MMC0*/
writel(PRCM_MOD_EN, &cmper->mmc0clkctrl);
while (readl(&cmper->mmc0clkctrl) != PRCM_MOD_EN)
;
/* i2c0 */
writel(PRCM_MOD_EN, &cmwkup->wkup_i2c0ctrl);
while (readl(&cmwkup->wkup_i2c0ctrl) != PRCM_MOD_EN)
;
/* gpio1 module */
writel(PRCM_MOD_EN, &cmper->gpio1clkctrl);
while (readl(&cmper->gpio1clkctrl) != PRCM_MOD_EN)
;
/* gpio2 module */
writel(PRCM_MOD_EN, &cmper->gpio2clkctrl);
while (readl(&cmper->gpio2clkctrl) != PRCM_MOD_EN)
;
/* gpio3 module */
writel(PRCM_MOD_EN, &cmper->gpio3clkctrl);
while (readl(&cmper->gpio3clkctrl) != PRCM_MOD_EN)
;
/* i2c1 */
writel(PRCM_MOD_EN, &cmper->i2c1clkctrl);
while (readl(&cmper->i2c1clkctrl) != PRCM_MOD_EN)
;
/* Ethernet */
writel(PRCM_MOD_EN, &cmper->cpgmac0clkctrl);
while ((readl(&cmper->cpgmac0clkctrl) & CPGMAC0_IDLE) != PRCM_FUNCTL)
;
/* spi0 */
writel(PRCM_MOD_EN, &cmper->spi0clkctrl);
while (readl(&cmper->spi0clkctrl) != PRCM_MOD_EN)
;
/* RTC */
writel(PRCM_MOD_EN, &cmrtc->rtcclkctrl);
while (readl(&cmrtc->rtcclkctrl) != PRCM_MOD_EN)
;
}
static void mpu_pll_config(void)
{
u32 clkmode, clksel, div_m2;
clkmode = readl(&cmwkup->clkmoddpllmpu);
clksel = readl(&cmwkup->clkseldpllmpu);
div_m2 = readl(&cmwkup->divm2dpllmpu);
/* Set the PLL to bypass Mode */
writel(PLL_BYPASS_MODE, &cmwkup->clkmoddpllmpu);
while (readl(&cmwkup->idlestdpllmpu) != ST_MN_BYPASS)
;
clksel = clksel & (~CLK_SEL_MASK);
clksel = clksel | ((MPUPLL_M << CLK_SEL_SHIFT) | MPUPLL_N);
writel(clksel, &cmwkup->clkseldpllmpu);
div_m2 = div_m2 & ~CLK_DIV_MASK;
div_m2 = div_m2 | MPUPLL_M2;
writel(div_m2, &cmwkup->divm2dpllmpu);
clkmode = clkmode | CLK_MODE_SEL;
writel(clkmode, &cmwkup->clkmoddpllmpu);
while (readl(&cmwkup->idlestdpllmpu) != ST_DPLL_CLK)
;
}
static void core_pll_config(void)
{
u32 clkmode, clksel, div_m4, div_m5, div_m6;
clkmode = readl(&cmwkup->clkmoddpllcore);
clksel = readl(&cmwkup->clkseldpllcore);
div_m4 = readl(&cmwkup->divm4dpllcore);
div_m5 = readl(&cmwkup->divm5dpllcore);
div_m6 = readl(&cmwkup->divm6dpllcore);
/* Set the PLL to bypass Mode */
writel(PLL_BYPASS_MODE, &cmwkup->clkmoddpllcore);
while (readl(&cmwkup->idlestdpllcore) != ST_MN_BYPASS)
;
clksel = clksel & (~CLK_SEL_MASK);
clksel = clksel | ((COREPLL_M << CLK_SEL_SHIFT) | COREPLL_N);
writel(clksel, &cmwkup->clkseldpllcore);
div_m4 = div_m4 & ~CLK_DIV_MASK;
div_m4 = div_m4 | COREPLL_M4;
writel(div_m4, &cmwkup->divm4dpllcore);
div_m5 = div_m5 & ~CLK_DIV_MASK;
div_m5 = div_m5 | COREPLL_M5;
writel(div_m5, &cmwkup->divm5dpllcore);
div_m6 = div_m6 & ~CLK_DIV_MASK;
div_m6 = div_m6 | COREPLL_M6;
writel(div_m6, &cmwkup->divm6dpllcore);
clkmode = clkmode | CLK_MODE_SEL;
writel(clkmode, &cmwkup->clkmoddpllcore);
while (readl(&cmwkup->idlestdpllcore) != ST_DPLL_CLK)
;
}
static void per_pll_config(void)
{
u32 clkmode, clksel, div_m2;
clkmode = readl(&cmwkup->clkmoddpllper);
clksel = readl(&cmwkup->clkseldpllper);
div_m2 = readl(&cmwkup->divm2dpllper);
/* Set the PLL to bypass Mode */
writel(PLL_BYPASS_MODE, &cmwkup->clkmoddpllper);
while (readl(&cmwkup->idlestdpllper) != ST_MN_BYPASS)
;
clksel = clksel & (~CLK_SEL_MASK);
clksel = clksel | ((PERPLL_M << CLK_SEL_SHIFT) | PERPLL_N);
writel(clksel, &cmwkup->clkseldpllper);
div_m2 = div_m2 & ~CLK_DIV2_MASK;
div_m2 = div_m2 | PERPLL_M2;
writel(div_m2, &cmwkup->divm2dpllper);
clkmode = clkmode | CLK_MODE_SEL;
writel(clkmode, &cmwkup->clkmoddpllper);
while (readl(&cmwkup->idlestdpllper) != ST_DPLL_CLK)
;
}
void ddr_pll_config(unsigned int ddrpll_m)
{
u32 clkmode, clksel, div_m2;
clkmode = readl(&cmwkup->clkmoddpllddr);
clksel = readl(&cmwkup->clkseldpllddr);
div_m2 = readl(&cmwkup->divm2dpllddr);
/* Set the PLL to bypass Mode */
clkmode = (clkmode & CLK_MODE_MASK) | PLL_BYPASS_MODE;
writel(clkmode, &cmwkup->clkmoddpllddr);
/* Wait till bypass mode is enabled */
while ((readl(&cmwkup->idlestdpllddr) & ST_MN_BYPASS)
!= ST_MN_BYPASS)
;
clksel = clksel & (~CLK_SEL_MASK);
clksel = clksel | ((ddrpll_m << CLK_SEL_SHIFT) | DDRPLL_N);
writel(clksel, &cmwkup->clkseldpllddr);
div_m2 = div_m2 & CLK_DIV_SEL;
div_m2 = div_m2 | DDRPLL_M2;
writel(div_m2, &cmwkup->divm2dpllddr);
clkmode = (clkmode & CLK_MODE_MASK) | CLK_MODE_SEL;
writel(clkmode, &cmwkup->clkmoddpllddr);
/* Wait till dpll is locked */
while ((readl(&cmwkup->idlestdpllddr) & ST_DPLL_CLK) != ST_DPLL_CLK)
;
}
void enable_emif_clocks(void)
{
/* Enable the EMIF_FW Functional clock */
writel(PRCM_MOD_EN, &cmper->emiffwclkctrl);
/* Enable EMIF0 Clock */
writel(PRCM_MOD_EN, &cmper->emifclkctrl);
/* Poll if module is functional */
while ((readl(&cmper->emifclkctrl)) != PRCM_MOD_EN)
;
}
/*
* Configure the PLL/PRCM for necessary peripherals
*/
void pll_init()
{
mpu_pll_config();
core_pll_config();
per_pll_config();
/* Enable the required interconnect clocks */
enable_interface_clocks();
/* Power domain wake up transition */
power_domain_wkup_transition();
/* Enable the required peripherals */
enable_per_clocks();
}