linux-sg2042/arch/arm/mach-lpc32xx/clock.c

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/*
* arch/arm/mach-lpc32xx/clock.c
*
* Author: Kevin Wells <kevin.wells@nxp.com>
*
* Copyright (C) 2010 NXP Semiconductors
*
* 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.
*/
/*
* LPC32xx clock management driver overview
*
* The LPC32XX contains a number of high level system clocks that can be
* generated from different sources. These system clocks are used to
* generate the CPU and bus rates and the individual peripheral clocks in
* the system. When Linux is started by the boot loader, the system
* clocks are already running. Stopping a system clock during normal
* Linux operation should never be attempted, as peripherals that require
* those clocks will quit working (ie, DRAM).
*
* The LPC32xx high level clock tree looks as follows. Clocks marked with
* an asterisk are always on and cannot be disabled. Clocks marked with
* an ampersand can only be disabled in CPU suspend mode. Clocks marked
* with a caret are always on if it is the selected clock for the SYSCLK
* source. The clock that isn't used for SYSCLK can be enabled and
* disabled normally.
* 32KHz oscillator*
* / | \
* RTC* PLL397^ TOUCH
* /
* Main oscillator^ /
* | \ /
* | SYSCLK&
* | \
* | \
* USB_PLL HCLK_PLL&
* | | |
* USB host/device PCLK& |
* | |
* Peripherals
*
* The CPU and chip bus rates are derived from the HCLK PLL, which can
* generate various clock rates up to 266MHz and beyond. The internal bus
* rates (PCLK and HCLK) are generated from dividers based on the HCLK
* PLL rate. HCLK can be a ratio of 1:1, 1:2, or 1:4 or HCLK PLL rate,
* while PCLK can be 1:1 to 1:32 of HCLK PLL rate. Most peripherals high
* level clocks are based on either HCLK or PCLK, but have their own
* dividers as part of the IP itself. Because of this, the system clock
* rates should not be changed.
*
* The HCLK PLL is clocked from SYSCLK, which can be derived from the
* main oscillator or PLL397. PLL397 generates a rate that is 397 times
* the 32KHz oscillator rate. The main oscillator runs at the selected
* oscillator/crystal rate on the mosc_in pin of the LPC32xx. This rate
* is normally 13MHz, but depends on the selection of external crystals
* or oscillators. If USB operation is required, the main oscillator must
* be used in the system.
*
* Switching SYSCLK between sources during normal Linux operation is not
* supported. SYSCLK is preset in the bootloader. Because of the
* complexities of clock management during clock frequency changes,
* there are some limitations to the clock driver explained below:
* - The PLL397 and main oscillator can be enabled and disabled by the
* clk_enable() and clk_disable() functions unless SYSCLK is based
* on that clock. This allows the other oscillator that isn't driving
* the HCLK PLL to be used as another system clock that can be routed
* to an external pin.
* - The muxed SYSCLK input and HCLK_PLL rate cannot be changed with
* this driver.
* - HCLK and PCLK rates cannot be changed as part of this driver.
* - Most peripherals have their own dividers are part of the peripheral
* block. Changing SYSCLK, HCLK PLL, HCLK, or PCLK sources or rates
* will also impact the individual peripheral rates.
*/
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/amba/bus.h>
#include <linux/amba/clcd.h>
#include <linux/clkdev.h>
#include <mach/hardware.h>
#include <mach/platform.h>
#include "clock.h"
#include "common.h"
static struct clk clk_armpll;
static struct clk clk_usbpll;
static DEFINE_MUTEX(clkm_lock);
/*
* Post divider values for PLLs based on selected register value
*/
static const u32 pll_postdivs[4] = {1, 2, 4, 8};
static unsigned long local_return_parent_rate(struct clk *clk)
{
/*
* If a clock has a rate of 0, then it inherits it's parent
* clock rate
*/
while (clk->rate == 0)
clk = clk->parent;
return clk->rate;
}
/* 32KHz clock has a fixed rate and is not stoppable */
static struct clk osc_32KHz = {
.rate = LPC32XX_CLOCK_OSC_FREQ,
.get_rate = local_return_parent_rate,
};
static int local_pll397_enable(struct clk *clk, int enable)
{
u32 reg;
unsigned long timeout = 1 + msecs_to_jiffies(10);
reg = __raw_readl(LPC32XX_CLKPWR_PLL397_CTRL);
if (enable == 0) {
reg |= LPC32XX_CLKPWR_SYSCTRL_PLL397_DIS;
__raw_writel(reg, LPC32XX_CLKPWR_PLL397_CTRL);
} else {
/* Enable PLL397 */
reg &= ~LPC32XX_CLKPWR_SYSCTRL_PLL397_DIS;
__raw_writel(reg, LPC32XX_CLKPWR_PLL397_CTRL);
/* Wait for PLL397 lock */
while (((__raw_readl(LPC32XX_CLKPWR_PLL397_CTRL) &
LPC32XX_CLKPWR_SYSCTRL_PLL397_STS) == 0) &&
(timeout > jiffies))
cpu_relax();
if ((__raw_readl(LPC32XX_CLKPWR_PLL397_CTRL) &
LPC32XX_CLKPWR_SYSCTRL_PLL397_STS) == 0)
return -ENODEV;
}
return 0;
}
static int local_oscmain_enable(struct clk *clk, int enable)
{
u32 reg;
unsigned long timeout = 1 + msecs_to_jiffies(10);
reg = __raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL);
if (enable == 0) {
reg |= LPC32XX_CLKPWR_MOSC_DISABLE;
__raw_writel(reg, LPC32XX_CLKPWR_MAIN_OSC_CTRL);
} else {
/* Enable main oscillator */
reg &= ~LPC32XX_CLKPWR_MOSC_DISABLE;
__raw_writel(reg, LPC32XX_CLKPWR_MAIN_OSC_CTRL);
/* Wait for main oscillator to start */
while (((__raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL) &
LPC32XX_CLKPWR_MOSC_DISABLE) != 0) &&
(timeout > jiffies))
cpu_relax();
if ((__raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL) &
LPC32XX_CLKPWR_MOSC_DISABLE) != 0)
return -ENODEV;
}
return 0;
}
static struct clk osc_pll397 = {
.parent = &osc_32KHz,
.enable = local_pll397_enable,
.rate = LPC32XX_CLOCK_OSC_FREQ * 397,
.get_rate = local_return_parent_rate,
};
static struct clk osc_main = {
.enable = local_oscmain_enable,
.rate = LPC32XX_MAIN_OSC_FREQ,
.get_rate = local_return_parent_rate,
};
static struct clk clk_sys;
/*
* Convert a PLL register value to a PLL output frequency
*/
u32 clk_get_pllrate_from_reg(u32 inputclk, u32 regval)
{
struct clk_pll_setup pllcfg;
pllcfg.cco_bypass_b15 = 0;
pllcfg.direct_output_b14 = 0;
pllcfg.fdbk_div_ctrl_b13 = 0;
if ((regval & LPC32XX_CLKPWR_HCLKPLL_CCO_BYPASS) != 0)
pllcfg.cco_bypass_b15 = 1;
if ((regval & LPC32XX_CLKPWR_HCLKPLL_POSTDIV_BYPASS) != 0)
pllcfg.direct_output_b14 = 1;
if ((regval & LPC32XX_CLKPWR_HCLKPLL_FDBK_SEL_FCLK) != 0)
pllcfg.fdbk_div_ctrl_b13 = 1;
pllcfg.pll_m = 1 + ((regval >> 1) & 0xFF);
pllcfg.pll_n = 1 + ((regval >> 9) & 0x3);
pllcfg.pll_p = pll_postdivs[((regval >> 11) & 0x3)];
return clk_check_pll_setup(inputclk, &pllcfg);
}
/*
* Setup the HCLK PLL with a PLL structure
*/
static u32 local_clk_pll_setup(struct clk_pll_setup *PllSetup)
{
u32 tv, tmp = 0;
if (PllSetup->analog_on != 0)
tmp |= LPC32XX_CLKPWR_HCLKPLL_POWER_UP;
if (PllSetup->cco_bypass_b15 != 0)
tmp |= LPC32XX_CLKPWR_HCLKPLL_CCO_BYPASS;
if (PllSetup->direct_output_b14 != 0)
tmp |= LPC32XX_CLKPWR_HCLKPLL_POSTDIV_BYPASS;
if (PllSetup->fdbk_div_ctrl_b13 != 0)
tmp |= LPC32XX_CLKPWR_HCLKPLL_FDBK_SEL_FCLK;
tv = ffs(PllSetup->pll_p) - 1;
if ((!is_power_of_2(PllSetup->pll_p)) || (tv > 3))
return 0;
tmp |= LPC32XX_CLKPWR_HCLKPLL_POSTDIV_2POW(tv);
tmp |= LPC32XX_CLKPWR_HCLKPLL_PREDIV_PLUS1(PllSetup->pll_n - 1);
tmp |= LPC32XX_CLKPWR_HCLKPLL_PLLM(PllSetup->pll_m - 1);
return tmp;
}
/*
* Update the ARM core PLL frequency rate variable from the actual PLL setting
*/
static void local_update_armpll_rate(void)
{
u32 clkin, pllreg;
clkin = clk_armpll.parent->rate;
pllreg = __raw_readl(LPC32XX_CLKPWR_HCLKPLL_CTRL) & 0x1FFFF;
clk_armpll.rate = clk_get_pllrate_from_reg(clkin, pllreg);
}
/*
* Find a PLL configuration for the selected input frequency
*/
static u32 local_clk_find_pll_cfg(u32 pllin_freq, u32 target_freq,
struct clk_pll_setup *pllsetup)
{
u32 ifreq, freqtol, m, n, p, fclkout;
/* Determine frequency tolerance limits */
freqtol = target_freq / 250;
ifreq = pllin_freq;
/* Is direct bypass mode possible? */
if (abs(pllin_freq - target_freq) <= freqtol) {
pllsetup->analog_on = 0;
pllsetup->cco_bypass_b15 = 1;
pllsetup->direct_output_b14 = 1;
pllsetup->fdbk_div_ctrl_b13 = 1;
pllsetup->pll_p = pll_postdivs[0];
pllsetup->pll_n = 1;
pllsetup->pll_m = 1;
return clk_check_pll_setup(ifreq, pllsetup);
} else if (target_freq <= ifreq) {
pllsetup->analog_on = 0;
pllsetup->cco_bypass_b15 = 1;
pllsetup->direct_output_b14 = 0;
pllsetup->fdbk_div_ctrl_b13 = 1;
pllsetup->pll_n = 1;
pllsetup->pll_m = 1;
for (p = 0; p <= 3; p++) {
pllsetup->pll_p = pll_postdivs[p];
fclkout = clk_check_pll_setup(ifreq, pllsetup);
if (abs(target_freq - fclkout) <= freqtol)
return fclkout;
}
}
/* Is direct mode possible? */
pllsetup->analog_on = 1;
pllsetup->cco_bypass_b15 = 0;
pllsetup->direct_output_b14 = 1;
pllsetup->fdbk_div_ctrl_b13 = 0;
pllsetup->pll_p = pll_postdivs[0];
for (m = 1; m <= 256; m++) {
for (n = 1; n <= 4; n++) {
/* Compute output frequency for this value */
pllsetup->pll_n = n;
pllsetup->pll_m = m;
fclkout = clk_check_pll_setup(ifreq,
pllsetup);
if (abs(target_freq - fclkout) <=
freqtol)
return fclkout;
}
}
/* Is integer mode possible? */
pllsetup->analog_on = 1;
pllsetup->cco_bypass_b15 = 0;
pllsetup->direct_output_b14 = 0;
pllsetup->fdbk_div_ctrl_b13 = 1;
for (m = 1; m <= 256; m++) {
for (n = 1; n <= 4; n++) {
for (p = 0; p < 4; p++) {
/* Compute output frequency */
pllsetup->pll_p = pll_postdivs[p];
pllsetup->pll_n = n;
pllsetup->pll_m = m;
fclkout = clk_check_pll_setup(
ifreq, pllsetup);
if (abs(target_freq - fclkout) <= freqtol)
return fclkout;
}
}
}
/* Try non-integer mode */
pllsetup->analog_on = 1;
pllsetup->cco_bypass_b15 = 0;
pllsetup->direct_output_b14 = 0;
pllsetup->fdbk_div_ctrl_b13 = 0;
for (m = 1; m <= 256; m++) {
for (n = 1; n <= 4; n++) {
for (p = 0; p < 4; p++) {
/* Compute output frequency */
pllsetup->pll_p = pll_postdivs[p];
pllsetup->pll_n = n;
pllsetup->pll_m = m;
fclkout = clk_check_pll_setup(
ifreq, pllsetup);
if (abs(target_freq - fclkout) <= freqtol)
return fclkout;
}
}
}
return 0;
}
static struct clk clk_armpll = {
.parent = &clk_sys,
.get_rate = local_return_parent_rate,
};
/*
* Setup the USB PLL with a PLL structure
*/
static u32 local_clk_usbpll_setup(struct clk_pll_setup *pHCLKPllSetup)
{
u32 reg, tmp = local_clk_pll_setup(pHCLKPllSetup);
reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL) & ~0x1FFFF;
reg |= tmp;
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
return clk_check_pll_setup(clk_usbpll.parent->rate,
pHCLKPllSetup);
}
static int local_usbpll_enable(struct clk *clk, int enable)
{
u32 reg;
int ret = -ENODEV;
unsigned long timeout = 1 + msecs_to_jiffies(10);
reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
if (enable == 0) {
reg &= ~(LPC32XX_CLKPWR_USBCTRL_CLK_EN1 |
LPC32XX_CLKPWR_USBCTRL_CLK_EN2);
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
} else if (reg & LPC32XX_CLKPWR_USBCTRL_PLL_PWRUP) {
reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN1;
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
/* Wait for PLL lock */
while ((timeout > jiffies) & (ret == -ENODEV)) {
reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
if (reg & LPC32XX_CLKPWR_USBCTRL_PLL_STS)
ret = 0;
}
if (ret == 0) {
reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN2;
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
}
}
return ret;
}
static unsigned long local_usbpll_round_rate(struct clk *clk,
unsigned long rate)
{
u32 clkin, usbdiv;
struct clk_pll_setup pllsetup;
/*
* Unlike other clocks, this clock has a KHz input rate, so bump
* it up to work with the PLL function
*/
rate = rate * 1000;
clkin = clk->parent->rate;
usbdiv = (__raw_readl(LPC32XX_CLKPWR_USBCLK_PDIV) &
LPC32XX_CLKPWR_USBPDIV_PLL_MASK) + 1;
clkin = clkin / usbdiv;
/* Try to find a good rate setup */
if (local_clk_find_pll_cfg(clkin, rate, &pllsetup) == 0)
return 0;
return clk_check_pll_setup(clkin, &pllsetup);
}
static int local_usbpll_set_rate(struct clk *clk, unsigned long rate)
{
u32 clkin, reg, usbdiv;
struct clk_pll_setup pllsetup;
/*
* Unlike other clocks, this clock has a KHz input rate, so bump
* it up to work with the PLL function
*/
rate = rate * 1000;
clkin = clk->get_rate(clk);
usbdiv = (__raw_readl(LPC32XX_CLKPWR_USBCLK_PDIV) &
LPC32XX_CLKPWR_USBPDIV_PLL_MASK) + 1;
clkin = clkin / usbdiv;
/* Try to find a good rate setup */
if (local_clk_find_pll_cfg(clkin, rate, &pllsetup) == 0)
return -EINVAL;
local_usbpll_enable(clk, 0);
reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN1;
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
pllsetup.analog_on = 1;
local_clk_usbpll_setup(&pllsetup);
clk->rate = clk_check_pll_setup(clkin, &pllsetup);
reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN2;
__raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
return 0;
}
static struct clk clk_usbpll = {
.parent = &osc_main,
.set_rate = local_usbpll_set_rate,
.enable = local_usbpll_enable,
.rate = 48000, /* In KHz */
.get_rate = local_return_parent_rate,
.round_rate = local_usbpll_round_rate,
};
static u32 clk_get_hclk_div(void)
{
static const u32 hclkdivs[4] = {1, 2, 4, 4};
return hclkdivs[LPC32XX_CLKPWR_HCLKDIV_DIV_2POW(
__raw_readl(LPC32XX_CLKPWR_HCLK_DIV))];
}
static struct clk clk_hclk = {
.parent = &clk_armpll,
.get_rate = local_return_parent_rate,
};
static struct clk clk_pclk = {
.parent = &clk_armpll,
.get_rate = local_return_parent_rate,
};
static int local_onoff_enable(struct clk *clk, int enable)
{
u32 tmp;
tmp = __raw_readl(clk->enable_reg);
if (enable == 0)
tmp &= ~clk->enable_mask;
else
tmp |= clk->enable_mask;
__raw_writel(tmp, clk->enable_reg);
return 0;
}
/* Peripheral clock sources */
static struct clk clk_timer0 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
.enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER0_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_timer1 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
.enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER1_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_timer2 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
.enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER2_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_timer3 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
.enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER3_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_wdt = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_TIMER_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_PWMCLK_WDOG_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_vfp9 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_DEBUG_CTRL,
.enable_mask = LPC32XX_CLKPWR_VFP_CLOCK_ENABLE_BIT,
.get_rate = local_return_parent_rate,
};
static struct clk clk_dma = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_DMA_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_DMACLKCTRL_CLK_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_uart3 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART3_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_uart4 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART4_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_uart5 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART5_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_uart6 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART6_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_i2c0 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_I2C_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_I2CCLK_I2C1CLK_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_i2c1 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_I2C_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_I2CCLK_I2C2CLK_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_i2c2 = {
.parent = &clk_pclk,
.enable = local_onoff_enable,
.enable_reg = io_p2v(LPC32XX_USB_BASE + 0xFF4),
.enable_mask = 0x4,
.get_rate = local_return_parent_rate,
};
static struct clk clk_ssp0 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_SSP_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_SSPCTRL_SSPCLK0_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_ssp1 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_SSP_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_SSPCTRL_SSPCLK1_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_kscan = {
.parent = &osc_32KHz,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_KEY_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_KEYCLKCTRL_CLK_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_nand = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_NAND_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_NANDCLK_SLCCLK_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_i2s0 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_I2S_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_I2SCTRL_I2SCLK0_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_i2s1 = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_I2S_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_I2SCTRL_I2SCLK1_EN,
.get_rate = local_return_parent_rate,
};
static struct clk clk_net = {
.parent = &clk_hclk,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_MACCLK_CTRL,
.enable_mask = (LPC32XX_CLKPWR_MACCTRL_DMACLK_EN |
LPC32XX_CLKPWR_MACCTRL_MMIOCLK_EN |
LPC32XX_CLKPWR_MACCTRL_HRCCLK_EN),
.get_rate = local_return_parent_rate,
};
static struct clk clk_rtc = {
.parent = &osc_32KHz,
.rate = 1, /* 1 Hz */
.get_rate = local_return_parent_rate,
};
static struct clk clk_usbd = {
.parent = &clk_usbpll,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_USB_CTRL,
.enable_mask = LPC32XX_CLKPWR_USBCTRL_HCLK_EN,
.get_rate = local_return_parent_rate,
};
static int tsc_onoff_enable(struct clk *clk, int enable)
{
u32 tmp;
/* Make sure 32KHz clock is the selected clock */
tmp = __raw_readl(LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
tmp &= ~LPC32XX_CLKPWR_ADCCTRL1_PCLK_SEL;
__raw_writel(tmp, LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
if (enable == 0)
__raw_writel(0, clk->enable_reg);
else
__raw_writel(clk->enable_mask, clk->enable_reg);
return 0;
}
static struct clk clk_tsc = {
.parent = &osc_32KHz,
.enable = tsc_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_ADC_CLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_ADC32CLKCTRL_CLK_EN,
.get_rate = local_return_parent_rate,
};
static int mmc_onoff_enable(struct clk *clk, int enable)
{
u32 tmp;
tmp = __raw_readl(LPC32XX_CLKPWR_MS_CTRL) &
~LPC32XX_CLKPWR_MSCARD_SDCARD_EN;
/* If rate is 0, disable clock */
if (enable != 0)
tmp |= LPC32XX_CLKPWR_MSCARD_SDCARD_EN;
__raw_writel(tmp, LPC32XX_CLKPWR_MS_CTRL);
return 0;
}
static unsigned long mmc_get_rate(struct clk *clk)
{
u32 div, rate, oldclk;
/* The MMC clock must be on when accessing an MMC register */
oldclk = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
__raw_writel(oldclk | LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
LPC32XX_CLKPWR_MS_CTRL);
div = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
__raw_writel(oldclk, LPC32XX_CLKPWR_MS_CTRL);
/* Get the parent clock rate */
rate = clk->parent->get_rate(clk->parent);
/* Get the MMC controller clock divider value */
div = div & LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(0xf);
if (!div)
div = 1;
return rate / div;
}
static unsigned long mmc_round_rate(struct clk *clk, unsigned long rate)
{
unsigned long div, prate;
/* Get the parent clock rate */
prate = clk->parent->get_rate(clk->parent);
if (rate >= prate)
return prate;
div = prate / rate;
if (div > 0xf)
div = 0xf;
return prate / div;
}
static int mmc_set_rate(struct clk *clk, unsigned long rate)
{
u32 oldclk, tmp;
unsigned long prate, div, crate = mmc_round_rate(clk, rate);
prate = clk->parent->get_rate(clk->parent);
div = prate / crate;
/* The MMC clock must be on when accessing an MMC register */
oldclk = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
__raw_writel(oldclk | LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
LPC32XX_CLKPWR_MS_CTRL);
tmp = __raw_readl(LPC32XX_CLKPWR_MS_CTRL) &
~LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(0xf);
tmp |= LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(div);
__raw_writel(tmp, LPC32XX_CLKPWR_MS_CTRL);
__raw_writel(oldclk, LPC32XX_CLKPWR_MS_CTRL);
return 0;
}
static struct clk clk_mmc = {
.parent = &clk_armpll,
.set_rate = mmc_set_rate,
.get_rate = mmc_get_rate,
.round_rate = mmc_round_rate,
.enable = mmc_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_MS_CTRL,
.enable_mask = LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
};
static unsigned long clcd_get_rate(struct clk *clk)
{
u32 tmp, div, rate, oldclk;
/* The LCD clock must be on when accessing an LCD register */
oldclk = __raw_readl(LPC32XX_CLKPWR_LCDCLK_CTRL);
__raw_writel(oldclk | LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
LPC32XX_CLKPWR_LCDCLK_CTRL);
tmp = __raw_readl(io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2));
__raw_writel(oldclk, LPC32XX_CLKPWR_LCDCLK_CTRL);
rate = clk->parent->get_rate(clk->parent);
/* Only supports internal clocking */
if (tmp & TIM2_BCD)
return rate;
div = (tmp & 0x1F) | ((tmp & 0xF8) >> 22);
tmp = rate / (2 + div);
return tmp;
}
static int clcd_set_rate(struct clk *clk, unsigned long rate)
{
u32 tmp, prate, div, oldclk;
/* The LCD clock must be on when accessing an LCD register */
oldclk = __raw_readl(LPC32XX_CLKPWR_LCDCLK_CTRL);
__raw_writel(oldclk | LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
LPC32XX_CLKPWR_LCDCLK_CTRL);
tmp = __raw_readl(io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2)) | TIM2_BCD;
prate = clk->parent->get_rate(clk->parent);
if (rate < prate) {
/* Find closest divider */
div = prate / rate;
if (div >= 2) {
div -= 2;
tmp &= ~TIM2_BCD;
}
tmp &= ~(0xF800001F);
tmp |= (div & 0x1F);
tmp |= (((div >> 5) & 0x1F) << 27);
}
__raw_writel(tmp, io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2));
__raw_writel(oldclk, LPC32XX_CLKPWR_LCDCLK_CTRL);
return 0;
}
static unsigned long clcd_round_rate(struct clk *clk, unsigned long rate)
{
u32 prate, div;
prate = clk->parent->get_rate(clk->parent);
if (rate >= prate)
rate = prate;
else {
div = prate / rate;
if (div > 0x3ff)
div = 0x3ff;
rate = prate / div;
}
return rate;
}
static struct clk clk_lcd = {
.parent = &clk_hclk,
.set_rate = clcd_set_rate,
.get_rate = clcd_get_rate,
.round_rate = clcd_round_rate,
.enable = local_onoff_enable,
.enable_reg = LPC32XX_CLKPWR_LCDCLK_CTRL,
.enable_mask = LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
};
static inline void clk_lock(void)
{
mutex_lock(&clkm_lock);
}
static inline void clk_unlock(void)
{
mutex_unlock(&clkm_lock);
}
static void local_clk_disable(struct clk *clk)
{
WARN_ON(clk->usecount == 0);
/* Don't attempt to disable clock if it has no users */
if (clk->usecount > 0) {
clk->usecount--;
/* Only disable clock when it has no more users */
if ((clk->usecount == 0) && (clk->enable))
clk->enable(clk, 0);
/* Check parent clocks, they may need to be disabled too */
if (clk->parent)
local_clk_disable(clk->parent);
}
}
static int local_clk_enable(struct clk *clk)
{
int ret = 0;
/* Enable parent clocks first and update use counts */
if (clk->parent)
ret = local_clk_enable(clk->parent);
if (!ret) {
/* Only enable clock if it's currently disabled */
if ((clk->usecount == 0) && (clk->enable))
ret = clk->enable(clk, 1);
if (!ret)
clk->usecount++;
else if (clk->parent)
local_clk_disable(clk->parent);
}
return ret;
}
/*
* clk_enable - inform the system when the clock source should be running.
*/
int clk_enable(struct clk *clk)
{
int ret;
clk_lock();
ret = local_clk_enable(clk);
clk_unlock();
return ret;
}
EXPORT_SYMBOL(clk_enable);
/*
* clk_disable - inform the system when the clock source is no longer required
*/
void clk_disable(struct clk *clk)
{
clk_lock();
local_clk_disable(clk);
clk_unlock();
}
EXPORT_SYMBOL(clk_disable);
/*
* clk_get_rate - obtain the current clock rate (in Hz) for a clock source
*/
unsigned long clk_get_rate(struct clk *clk)
{
unsigned long rate;
clk_lock();
rate = clk->get_rate(clk);
clk_unlock();
return rate;
}
EXPORT_SYMBOL(clk_get_rate);
/*
* clk_set_rate - set the clock rate for a clock source
*/
int clk_set_rate(struct clk *clk, unsigned long rate)
{
int ret = -EINVAL;
/*
* Most system clocks can only be enabled or disabled, with
* the actual rate set as part of the peripheral dividers
* instead of high level clock control
*/
if (clk->set_rate) {
clk_lock();
ret = clk->set_rate(clk, rate);
clk_unlock();
}
return ret;
}
EXPORT_SYMBOL(clk_set_rate);
/*
* clk_round_rate - adjust a rate to the exact rate a clock can provide
*/
long clk_round_rate(struct clk *clk, unsigned long rate)
{
clk_lock();
if (clk->round_rate)
rate = clk->round_rate(clk, rate);
else
rate = clk->get_rate(clk);
clk_unlock();
return rate;
}
EXPORT_SYMBOL(clk_round_rate);
/*
* clk_set_parent - set the parent clock source for this clock
*/
int clk_set_parent(struct clk *clk, struct clk *parent)
{
/* Clock re-parenting is not supported */
return -EINVAL;
}
EXPORT_SYMBOL(clk_set_parent);
/*
* clk_get_parent - get the parent clock source for this clock
*/
struct clk *clk_get_parent(struct clk *clk)
{
return clk->parent;
}
EXPORT_SYMBOL(clk_get_parent);
#define _REGISTER_CLOCK(d, n, c) \
{ \
.dev_id = (d), \
.con_id = (n), \
.clk = &(c), \
},
static struct clk_lookup lookups[] = {
_REGISTER_CLOCK(NULL, "osc_32KHz", osc_32KHz)
_REGISTER_CLOCK(NULL, "osc_pll397", osc_pll397)
_REGISTER_CLOCK(NULL, "osc_main", osc_main)
_REGISTER_CLOCK(NULL, "sys_ck", clk_sys)
_REGISTER_CLOCK(NULL, "arm_pll_ck", clk_armpll)
_REGISTER_CLOCK(NULL, "ck_pll5", clk_usbpll)
_REGISTER_CLOCK(NULL, "hclk_ck", clk_hclk)
_REGISTER_CLOCK(NULL, "pclk_ck", clk_pclk)
_REGISTER_CLOCK(NULL, "timer0_ck", clk_timer0)
_REGISTER_CLOCK(NULL, "timer1_ck", clk_timer1)
_REGISTER_CLOCK(NULL, "timer2_ck", clk_timer2)
_REGISTER_CLOCK(NULL, "timer3_ck", clk_timer3)
_REGISTER_CLOCK(NULL, "vfp9_ck", clk_vfp9)
_REGISTER_CLOCK(NULL, "clk_dmac", clk_dma)
_REGISTER_CLOCK("pnx4008-watchdog", NULL, clk_wdt)
_REGISTER_CLOCK(NULL, "uart3_ck", clk_uart3)
_REGISTER_CLOCK(NULL, "uart4_ck", clk_uart4)
_REGISTER_CLOCK(NULL, "uart5_ck", clk_uart5)
_REGISTER_CLOCK(NULL, "uart6_ck", clk_uart6)
_REGISTER_CLOCK("pnx-i2c.0", NULL, clk_i2c0)
_REGISTER_CLOCK("pnx-i2c.1", NULL, clk_i2c1)
_REGISTER_CLOCK("pnx-i2c.2", NULL, clk_i2c2)
_REGISTER_CLOCK("dev:ssp0", NULL, clk_ssp0)
_REGISTER_CLOCK("dev:ssp1", NULL, clk_ssp1)
_REGISTER_CLOCK("lpc32xx_keys.0", NULL, clk_kscan)
_REGISTER_CLOCK("lpc32xx-nand.0", "nand_ck", clk_nand)
_REGISTER_CLOCK("tbd", "i2s0_ck", clk_i2s0)
_REGISTER_CLOCK("tbd", "i2s1_ck", clk_i2s1)
_REGISTER_CLOCK("ts-lpc32xx", NULL, clk_tsc)
_REGISTER_CLOCK("dev:mmc0", "MCLK", clk_mmc)
_REGISTER_CLOCK("lpc-net.0", NULL, clk_net)
_REGISTER_CLOCK("dev:clcd", NULL, clk_lcd)
_REGISTER_CLOCK("lpc32xx_udc", "ck_usbd", clk_usbd)
_REGISTER_CLOCK("lpc32xx_rtc", NULL, clk_rtc)
};
static int __init clk_init(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(lookups); i++)
clkdev_add(&lookups[i]);
/*
* Setup muxed SYSCLK for HCLK PLL base -this selects the
* parent clock used for the ARM PLL and is used to derive
* the many system clock rates in the device.
*/
if (clk_is_sysclk_mainosc() != 0)
clk_sys.parent = &osc_main;
else
clk_sys.parent = &osc_pll397;
clk_sys.rate = clk_sys.parent->rate;
/* Compute the current ARM PLL and USB PLL frequencies */
local_update_armpll_rate();
/* Compute HCLK and PCLK bus rates */
clk_hclk.rate = clk_hclk.parent->rate / clk_get_hclk_div();
clk_pclk.rate = clk_pclk.parent->rate / clk_get_pclk_div();
/*
* Enable system clocks - this step is somewhat formal, as the
* clocks are already running, but it does get the clock data
* inline with the actual system state. Never disable these
* clocks as they will only stop if the system is going to sleep.
* In that case, the chip/system power management functions will
* handle clock gating.
*/
if (clk_enable(&clk_hclk) || clk_enable(&clk_pclk))
printk(KERN_ERR "Error enabling system HCLK and PCLK\n");
/*
* Timers 0 and 1 were enabled and are being used by the high
* resolution tick function prior to this driver being initialized.
* Tag them now as used.
*/
if (clk_enable(&clk_timer0) || clk_enable(&clk_timer1))
printk(KERN_ERR "Error enabling timer tick clocks\n");
return 0;
}
core_initcall(clk_init);