diff options
author | Kevin Wells <wellsk40@gmail.com> | 2010-02-26 15:53:40 -0800 |
---|---|---|
committer | Kevin Wells <wellsk40@gmail.com> | 2010-07-27 03:08:09 -0700 |
commit | b9cc4bf6656d5f349c283e6ac267b852b7a2e42e (patch) | |
tree | 22d6dfdbbece219091183f441b8cd86e43b73866 /arch/arm | |
parent | 343d3537917bd74648fa2a360b42f64ad5ec551d (diff) |
ARM: LPC32XX: Clock driver
Clock driver for the LPC32XX architecture
Signed-off-by: Kevin Wells <wellsk40@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/mach-lpc32xx/clock.c | 1137 | ||||
-rw-r--r-- | arch/arm/mach-lpc32xx/clock.h | 38 |
2 files changed, 1175 insertions, 0 deletions
diff --git a/arch/arm/mach-lpc32xx/clock.c b/arch/arm/mach-lpc32xx/clock.c new file mode 100644 index 00000000000..32d63796430 --- /dev/null +++ b/arch/arm/mach-lpc32xx/clock.c @@ -0,0 +1,1137 @@ +/* + * 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 <mach/hardware.h> +#include <asm/clkdev.h> +#include <mach/clkdev.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("lpc32xx-ts", 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); + diff --git a/arch/arm/mach-lpc32xx/clock.h b/arch/arm/mach-lpc32xx/clock.h new file mode 100644 index 00000000000..c0a8434307f --- /dev/null +++ b/arch/arm/mach-lpc32xx/clock.h @@ -0,0 +1,38 @@ +/* + * arch/arm/mach-lpc32xx/clock.h + * + * 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. + */ + +#ifndef __LPC32XX_CLOCK_H +#define __LPC32XX_CLOCK_H + +struct clk { + struct list_head node; + struct clk *parent; + u32 rate; + u32 usecount; + + int (*set_rate) (struct clk *, unsigned long); + unsigned long (*round_rate) (struct clk *, unsigned long); + unsigned long (*get_rate) (struct clk *clk); + int (*enable) (struct clk *, int); + + /* Register address and bit mask for simple clocks */ + void __iomem *enable_reg; + u32 enable_mask; +}; + +#endif |