diff options
Diffstat (limited to 'arch/arm/cpu/armv7/tegra2/clock.c')
-rw-r--r-- | arch/arm/cpu/armv7/tegra2/clock.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/tegra2/clock.c b/arch/arm/cpu/armv7/tegra2/clock.c new file mode 100644 index 0000000..67eed14 --- /dev/null +++ b/arch/arm/cpu/armv7/tegra2/clock.c @@ -0,0 +1,158 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. + * See file CREDITS for list of people who contributed to this + * project. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +/* Tegra2 Clock control functions */ + +#include <asm/io.h> +#include <asm/arch/clk_rst.h> +#include <asm/arch/clock.h> +#include <asm/arch/timer.h> +#include <asm/arch/tegra2.h> +#include <common.h> + +#ifdef DEBUG +#define assert(x) \ + ({ if (!(x)) printf("Assertion failure '%s' %s line %d\n", \ + #x, __FILE__, __LINE__); }) +#else +#define assert(x) +#endif + +/* + * Get the oscillator frequency, from the corresponding hardware configuration + * field. + */ +enum clock_osc_freq clock_get_osc_freq(void) +{ + struct clk_rst_ctlr *clkrst = + (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; + u32 reg; + + reg = readl(&clkrst->crc_osc_ctrl); + return (reg & OSC_FREQ_MASK) >> OSC_FREQ_SHIFT; +} + +unsigned long clock_start_pll(enum clock_pll_id clkid, u32 divm, u32 divn, + u32 divp, u32 cpcon, u32 lfcon) +{ + struct clk_rst_ctlr *clkrst = + (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; + u32 data; + struct clk_pll *pll; + + assert(clock_pll_id_isvalid(clkid)); + pll = &clkrst->crc_pll[clkid]; + + /* + * We cheat by treating all PLL (except PLLU) in the same fashion. + * This works only because: + * - same fields are always mapped at same offsets, except DCCON + * - DCCON is always 0, doesn't conflict + * - M,N, P of PLLP values are ignored for PLLP + */ + data = (cpcon << PLL_CPCON_SHIFT) | (lfcon << PLL_LFCON_SHIFT); + writel(data, &pll->pll_misc); + + data = (divm << PLL_DIVM_SHIFT) | (divn << PLL_DIVN_SHIFT) | + (0 << PLL_BYPASS_SHIFT) | (1 << PLL_ENABLE_SHIFT); + + if (clkid == CLOCK_PLL_ID_USB) + data |= divp << PLLU_VCO_FREQ_SHIFT; + else + data |= divp << PLL_DIVP_SHIFT; + writel(data, &pll->pll_base); + + /* calculate the stable time */ + return timer_get_us() + CLOCK_PLL_STABLE_DELAY_US; +} + +void clock_set_enable(enum periph_id periph_id, int enable) +{ + struct clk_rst_ctlr *clkrst = + (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; + u32 *clk = &clkrst->crc_clk_out_enb[PERIPH_REG(periph_id)]; + u32 reg; + + /* Enable/disable the clock to this peripheral */ + assert(clock_periph_id_isvalid(periph_id)); + reg = readl(clk); + if (enable) + reg |= PERIPH_MASK(periph_id); + else + reg &= ~PERIPH_MASK(periph_id); + writel(reg, clk); +} + +void clock_enable(enum periph_id clkid) +{ + clock_set_enable(clkid, 1); +} + +void clock_disable(enum periph_id clkid) +{ + clock_set_enable(clkid, 0); +} + +void reset_set_enable(enum periph_id periph_id, int enable) +{ + struct clk_rst_ctlr *clkrst = + (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; + u32 *reset = &clkrst->crc_rst_dev[PERIPH_REG(periph_id)]; + u32 reg; + + /* Enable/disable reset to the peripheral */ + assert(clock_periph_id_isvalid(periph_id)); + reg = readl(reset); + if (enable) + reg |= PERIPH_MASK(periph_id); + else + reg &= ~PERIPH_MASK(periph_id); + writel(reg, reset); +} + +void reset_periph(enum periph_id periph_id, int us_delay) +{ + /* Put peripheral into reset */ + reset_set_enable(periph_id, 1); + udelay(us_delay); + + /* Remove reset */ + reset_set_enable(periph_id, 0); + + udelay(us_delay); +} + +void reset_cmplx_set_enable(int cpu, int which, int reset) +{ + struct clk_rst_ctlr *clkrst = + (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; + u32 mask; + + /* Form the mask, which depends on the cpu chosen. Tegra2 has 2 */ + assert(cpu >= 0 && cpu < 2); + mask = which << cpu; + + /* either enable or disable those reset for that CPU */ + if (reset) + writel(mask, &clkrst->crc_cpu_cmplx_set); + else + writel(mask, &clkrst->crc_cpu_cmplx_clr); +} |