| /* |
| * Copyright (c) 2010-2013, NVIDIA CORPORATION. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms and conditions of the GNU General Public License, |
| * version 2, as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| /* Tegra SoC common clock control functions */ |
| |
| #include <common.h> |
| #include <asm/io.h> |
| #include <asm/arch/clock.h> |
| #include <asm/arch/tegra.h> |
| #include <asm/arch-tegra/clk_rst.h> |
| #include <asm/arch-tegra/timer.h> |
| #include <div64.h> |
| #include <fdtdec.h> |
| |
| /* |
| * This is our record of the current clock rate of each clock. We don't |
| * fill all of these in since we are only really interested in clocks which |
| * we use as parents. |
| */ |
| static unsigned pll_rate[CLOCK_ID_COUNT]; |
| |
| /* |
| * The oscillator frequency is fixed to one of four set values. Based on this |
| * the other clocks are set up appropriately. |
| */ |
| static unsigned osc_freq[CLOCK_OSC_FREQ_COUNT] = { |
| 13000000, |
| 19200000, |
| 12000000, |
| 26000000, |
| }; |
| |
| /* return 1 if a peripheral ID is in range */ |
| #define clock_type_id_isvalid(id) ((id) >= 0 && \ |
| (id) < CLOCK_TYPE_COUNT) |
| |
| char pllp_valid = 1; /* PLLP is set up correctly */ |
| |
| /* return 1 if a periphc_internal_id is in range */ |
| #define periphc_internal_id_isvalid(id) ((id) >= 0 && \ |
| (id) < PERIPHC_COUNT) |
| |
| /* number of clock outputs of a PLL */ |
| static const u8 pll_num_clkouts[] = { |
| 1, /* PLLC */ |
| 1, /* PLLM */ |
| 4, /* PLLP */ |
| 1, /* PLLA */ |
| 0, /* PLLU */ |
| 0, /* PLLD */ |
| }; |
| |
| int clock_get_osc_bypass(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_XOBP_MASK) >> OSC_XOBP_SHIFT; |
| } |
| |
| /* Returns a pointer to the registers of the given pll */ |
| static struct clk_pll *get_pll(enum clock_id clkid) |
| { |
| struct clk_rst_ctlr *clkrst = |
| (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; |
| |
| assert(clock_id_is_pll(clkid)); |
| return &clkrst->crc_pll[clkid]; |
| } |
| |
| int clock_ll_read_pll(enum clock_id clkid, u32 *divm, u32 *divn, |
| u32 *divp, u32 *cpcon, u32 *lfcon) |
| { |
| struct clk_pll *pll = get_pll(clkid); |
| u32 data; |
| |
| assert(clkid != CLOCK_ID_USB); |
| |
| /* Safety check, adds to code size but is small */ |
| if (!clock_id_is_pll(clkid) || clkid == CLOCK_ID_USB) |
| return -1; |
| data = readl(&pll->pll_base); |
| *divm = (data & PLL_DIVM_MASK) >> PLL_DIVM_SHIFT; |
| *divn = (data & PLL_DIVN_MASK) >> PLL_DIVN_SHIFT; |
| *divp = (data & PLL_DIVP_MASK) >> PLL_DIVP_SHIFT; |
| data = readl(&pll->pll_misc); |
| *cpcon = (data & PLL_CPCON_MASK) >> PLL_CPCON_SHIFT; |
| *lfcon = (data & PLL_LFCON_MASK) >> PLL_LFCON_SHIFT; |
| |
| return 0; |
| } |
| |
| unsigned long clock_start_pll(enum clock_id clkid, u32 divm, u32 divn, |
| u32 divp, u32 cpcon, u32 lfcon) |
| { |
| struct clk_pll *pll = get_pll(clkid); |
| u32 data; |
| |
| /* |
| * 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_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_ll_set_source_divisor(enum periph_id periph_id, unsigned source, |
| unsigned divisor) |
| { |
| u32 *reg = get_periph_source_reg(periph_id); |
| u32 value; |
| |
| value = readl(reg); |
| |
| value &= ~OUT_CLK_SOURCE_MASK; |
| value |= source << OUT_CLK_SOURCE_SHIFT; |
| |
| value &= ~OUT_CLK_DIVISOR_MASK; |
| value |= divisor << OUT_CLK_DIVISOR_SHIFT; |
| |
| writel(value, reg); |
| } |
| |
| void clock_ll_set_source(enum periph_id periph_id, unsigned source) |
| { |
| u32 *reg = get_periph_source_reg(periph_id); |
| |
| clrsetbits_le32(reg, OUT_CLK_SOURCE_MASK, |
| source << OUT_CLK_SOURCE_SHIFT); |
| } |
| |
| /** |
| * Given the parent's rate and the required rate for the children, this works |
| * out the peripheral clock divider to use, in 7.1 binary format. |
| * |
| * @param divider_bits number of divider bits (8 or 16) |
| * @param parent_rate clock rate of parent clock in Hz |
| * @param rate required clock rate for this clock |
| * @return divider which should be used |
| */ |
| static int clk_get_divider(unsigned divider_bits, unsigned long parent_rate, |
| unsigned long rate) |
| { |
| u64 divider = parent_rate * 2; |
| unsigned max_divider = 1 << divider_bits; |
| |
| divider += rate - 1; |
| do_div(divider, rate); |
| |
| if ((s64)divider - 2 < 0) |
| return 0; |
| |
| if ((s64)divider - 2 >= max_divider) |
| return -1; |
| |
| return divider - 2; |
| } |
| |
| int clock_set_pllout(enum clock_id clkid, enum pll_out_id pllout, unsigned rate) |
| { |
| struct clk_pll *pll = get_pll(clkid); |
| int data = 0, div = 0, offset = 0; |
| |
| if (!clock_id_is_pll(clkid)) |
| return -1; |
| |
| if (pllout + 1 > pll_num_clkouts[clkid]) |
| return -1; |
| |
| div = clk_get_divider(8, pll_rate[clkid], rate); |
| |
| if (div < 0) |
| return -1; |
| |
| /* out2 and out4 are in the high part of the register */ |
| if (pllout == PLL_OUT2 || pllout == PLL_OUT4) |
| offset = 16; |
| |
| data = (div << PLL_OUT_RATIO_SHIFT) | |
| PLL_OUT_OVRRIDE | PLL_OUT_CLKEN | PLL_OUT_RSTN; |
| clrsetbits_le32(&pll->pll_out[pllout >> 1], |
| PLL_OUT_RATIO_MASK << offset, data << offset); |
| |
| return 0; |
| } |
| |
| /** |
| * Given the parent's rate and the divider in 7.1 format, this works out the |
| * resulting peripheral clock rate. |
| * |
| * @param parent_rate clock rate of parent clock in Hz |
| * @param divider which should be used in 7.1 format |
| * @return effective clock rate of peripheral |
| */ |
| static unsigned long get_rate_from_divider(unsigned long parent_rate, |
| int divider) |
| { |
| u64 rate; |
| |
| rate = (u64)parent_rate * 2; |
| do_div(rate, divider + 2); |
| return rate; |
| } |
| |
| unsigned long clock_get_periph_rate(enum periph_id periph_id, |
| enum clock_id parent) |
| { |
| u32 *reg = get_periph_source_reg(periph_id); |
| |
| return get_rate_from_divider(pll_rate[parent], |
| (readl(reg) & OUT_CLK_DIVISOR_MASK) >> OUT_CLK_DIVISOR_SHIFT); |
| } |
| |
| /** |
| * Find the best available 7.1 format divisor given a parent clock rate and |
| * required child clock rate. This function assumes that a second-stage |
| * divisor is available which can divide by powers of 2 from 1 to 256. |
| * |
| * @param divider_bits number of divider bits (8 or 16) |
| * @param parent_rate clock rate of parent clock in Hz |
| * @param rate required clock rate for this clock |
| * @param extra_div value for the second-stage divisor (not set if this |
| * function returns -1. |
| * @return divider which should be used, or -1 if nothing is valid |
| * |
| */ |
| static int find_best_divider(unsigned divider_bits, unsigned long parent_rate, |
| unsigned long rate, int *extra_div) |
| { |
| int shift; |
| int best_divider = -1; |
| int best_error = rate; |
| |
| /* try dividers from 1 to 256 and find closest match */ |
| for (shift = 0; shift <= 8 && best_error > 0; shift++) { |
| unsigned divided_parent = parent_rate >> shift; |
| int divider = clk_get_divider(divider_bits, divided_parent, |
| rate); |
| unsigned effective_rate = get_rate_from_divider(divided_parent, |
| divider); |
| int error = rate - effective_rate; |
| |
| /* Given a valid divider, look for the lowest error */ |
| if (divider != -1 && error < best_error) { |
| best_error = error; |
| *extra_div = 1 << shift; |
| best_divider = divider; |
| } |
| } |
| |
| /* return what we found - *extra_div will already be set */ |
| return best_divider; |
| } |
| |
| /** |
| * Adjust peripheral PLL to use the given divider and source. |
| * |
| * @param periph_id peripheral to adjust |
| * @param source Source number (0-3 or 0-7) |
| * @param mux_bits Number of mux bits (2 or 4) |
| * @param divider Required divider in 7.1 or 15.1 format |
| * @return 0 if ok, -1 on error (requesting a parent clock which is not valid |
| * for this peripheral) |
| */ |
| static int adjust_periph_pll(enum periph_id periph_id, int source, |
| int mux_bits, unsigned divider) |
| { |
| u32 *reg = get_periph_source_reg(periph_id); |
| |
| clrsetbits_le32(reg, OUT_CLK_DIVISOR_MASK, |
| divider << OUT_CLK_DIVISOR_SHIFT); |
| udelay(1); |
| |
| /* work out the source clock and set it */ |
| if (source < 0) |
| return -1; |
| if (mux_bits == 4) { |
| clrsetbits_le32(reg, OUT_CLK_SOURCE4_MASK, |
| source << OUT_CLK_SOURCE4_SHIFT); |
| } else { |
| clrsetbits_le32(reg, OUT_CLK_SOURCE_MASK, |
| source << OUT_CLK_SOURCE_SHIFT); |
| } |
| udelay(2); |
| return 0; |
| } |
| |
| unsigned clock_adjust_periph_pll_div(enum periph_id periph_id, |
| enum clock_id parent, unsigned rate, int *extra_div) |
| { |
| unsigned effective_rate; |
| int mux_bits, divider_bits, source; |
| int divider; |
| int xdiv = 0; |
| |
| /* work out the source clock and set it */ |
| source = get_periph_clock_source(periph_id, parent, &mux_bits, |
| ÷r_bits); |
| |
| divider = find_best_divider(divider_bits, pll_rate[parent], |
| rate, &xdiv); |
| if (extra_div) |
| *extra_div = xdiv; |
| |
| assert(divider >= 0); |
| if (adjust_periph_pll(periph_id, source, mux_bits, divider)) |
| return -1U; |
| debug("periph %d, rate=%d, reg=%p = %x\n", periph_id, rate, |
| get_periph_source_reg(periph_id), |
| readl(get_periph_source_reg(periph_id))); |
| |
| /* Check what we ended up with. This shouldn't matter though */ |
| effective_rate = clock_get_periph_rate(periph_id, parent); |
| if (extra_div) |
| effective_rate /= *extra_div; |
| if (rate != effective_rate) |
| debug("Requested clock rate %u not honored (got %u)\n", |
| rate, effective_rate); |
| return effective_rate; |
| } |
| |
| unsigned clock_start_periph_pll(enum periph_id periph_id, |
| enum clock_id parent, unsigned rate) |
| { |
| unsigned effective_rate; |
| |
| reset_set_enable(periph_id, 1); |
| clock_enable(periph_id); |
| |
| effective_rate = clock_adjust_periph_pll_div(periph_id, parent, rate, |
| NULL); |
| |
| reset_set_enable(periph_id, 0); |
| return effective_rate; |
| } |
| |
| 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_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 (2 or 4) */ |
| assert(cpu >= 0 && cpu < MAX_NUM_CPU); |
| 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); |
| } |
| |
| unsigned clock_get_rate(enum clock_id clkid) |
| { |
| struct clk_pll *pll; |
| u32 base; |
| u32 divm; |
| u64 parent_rate; |
| u64 rate; |
| |
| parent_rate = osc_freq[clock_get_osc_freq()]; |
| if (clkid == CLOCK_ID_OSC) |
| return parent_rate; |
| |
| pll = get_pll(clkid); |
| base = readl(&pll->pll_base); |
| |
| /* Oh for bf_unpack()... */ |
| rate = parent_rate * ((base & PLL_DIVN_MASK) >> PLL_DIVN_SHIFT); |
| divm = (base & PLL_DIVM_MASK) >> PLL_DIVM_SHIFT; |
| if (clkid == CLOCK_ID_USB) |
| divm <<= (base & PLLU_VCO_FREQ_MASK) >> PLLU_VCO_FREQ_SHIFT; |
| else |
| divm <<= (base & PLL_DIVP_MASK) >> PLL_DIVP_SHIFT; |
| do_div(rate, divm); |
| return rate; |
| } |
| |
| /** |
| * Set the output frequency you want for each PLL clock. |
| * PLL output frequencies are programmed by setting their N, M and P values. |
| * The governing equations are: |
| * VCO = (Fi / m) * n, Fo = VCO / (2^p) |
| * where Fo is the output frequency from the PLL. |
| * Example: Set the output frequency to 216Mhz(Fo) with 12Mhz OSC(Fi) |
| * 216Mhz = ((12Mhz / m) * n) / (2^p) so n=432,m=12,p=1 |
| * Please see Tegra TRM section 5.3 to get the detail for PLL Programming |
| * |
| * @param n PLL feedback divider(DIVN) |
| * @param m PLL input divider(DIVN) |
| * @param p post divider(DIVP) |
| * @param cpcon base PLL charge pump(CPCON) |
| * @return 0 if ok, -1 on error (the requested PLL is incorrect and cannot |
| * be overriden), 1 if PLL is already correct |
| */ |
| int clock_set_rate(enum clock_id clkid, u32 n, u32 m, u32 p, u32 cpcon) |
| { |
| u32 base_reg; |
| u32 misc_reg; |
| struct clk_pll *pll; |
| |
| pll = get_pll(clkid); |
| |
| base_reg = readl(&pll->pll_base); |
| |
| /* Set BYPASS, m, n and p to PLL_BASE */ |
| base_reg &= ~PLL_DIVM_MASK; |
| base_reg |= m << PLL_DIVM_SHIFT; |
| |
| base_reg &= ~PLL_DIVN_MASK; |
| base_reg |= n << PLL_DIVN_SHIFT; |
| |
| base_reg &= ~PLL_DIVP_MASK; |
| base_reg |= p << PLL_DIVP_SHIFT; |
| |
| if (clkid == CLOCK_ID_PERIPH) { |
| /* |
| * If the PLL is already set up, check that it is correct |
| * and record this info for clock_verify() to check. |
| */ |
| if (base_reg & PLL_BASE_OVRRIDE_MASK) { |
| base_reg |= PLL_ENABLE_MASK; |
| if (base_reg != readl(&pll->pll_base)) |
| pllp_valid = 0; |
| return pllp_valid ? 1 : -1; |
| } |
| base_reg |= PLL_BASE_OVRRIDE_MASK; |
| } |
| |
| base_reg |= PLL_BYPASS_MASK; |
| writel(base_reg, &pll->pll_base); |
| |
| /* Set cpcon to PLL_MISC */ |
| misc_reg = readl(&pll->pll_misc); |
| misc_reg &= ~PLL_CPCON_MASK; |
| misc_reg |= cpcon << PLL_CPCON_SHIFT; |
| writel(misc_reg, &pll->pll_misc); |
| |
| /* Enable PLL */ |
| base_reg |= PLL_ENABLE_MASK; |
| writel(base_reg, &pll->pll_base); |
| |
| /* Disable BYPASS */ |
| base_reg &= ~PLL_BYPASS_MASK; |
| writel(base_reg, &pll->pll_base); |
| |
| return 0; |
| } |
| |
| void clock_ll_start_uart(enum periph_id periph_id) |
| { |
| /* Assert UART reset and enable clock */ |
| reset_set_enable(periph_id, 1); |
| clock_enable(periph_id); |
| clock_ll_set_source(periph_id, 0); /* UARTx_CLK_SRC = 00, PLLP_OUT0 */ |
| |
| /* wait for 2us */ |
| udelay(2); |
| |
| /* De-assert reset to UART */ |
| reset_set_enable(periph_id, 0); |
| } |
| |
| #ifdef CONFIG_OF_CONTROL |
| int clock_decode_periph_id(const void *blob, int node) |
| { |
| enum periph_id id; |
| u32 cell[2]; |
| int err; |
| |
| err = fdtdec_get_int_array(blob, node, "clocks", cell, |
| ARRAY_SIZE(cell)); |
| if (err) |
| return -1; |
| id = clk_id_to_periph_id(cell[1]); |
| assert(clock_periph_id_isvalid(id)); |
| return id; |
| } |
| #endif /* CONFIG_OF_CONTROL */ |
| |
| int clock_verify(void) |
| { |
| struct clk_pll *pll = get_pll(CLOCK_ID_PERIPH); |
| u32 reg = readl(&pll->pll_base); |
| |
| if (!pllp_valid) { |
| printf("Warning: PLLP %x is not correct\n", reg); |
| return -1; |
| } |
| debug("PLLP %x is correct\n", reg); |
| return 0; |
| } |
| |
| void clock_init(void) |
| { |
| pll_rate[CLOCK_ID_MEMORY] = clock_get_rate(CLOCK_ID_MEMORY); |
| pll_rate[CLOCK_ID_PERIPH] = clock_get_rate(CLOCK_ID_PERIPH); |
| pll_rate[CLOCK_ID_CGENERAL] = clock_get_rate(CLOCK_ID_CGENERAL); |
| pll_rate[CLOCK_ID_OSC] = clock_get_rate(CLOCK_ID_OSC); |
| pll_rate[CLOCK_ID_SFROM32KHZ] = 32768; |
| pll_rate[CLOCK_ID_XCPU] = clock_get_rate(CLOCK_ID_XCPU); |
| debug("Osc = %d\n", pll_rate[CLOCK_ID_OSC]); |
| debug("PLLM = %d\n", pll_rate[CLOCK_ID_MEMORY]); |
| debug("PLLP = %d\n", pll_rate[CLOCK_ID_PERIPH]); |
| debug("PLLC = %d\n", pll_rate[CLOCK_ID_CGENERAL]); |
| debug("PLLX = %d\n", pll_rate[CLOCK_ID_XCPU]); |
| |
| /* Do any special system timer/TSC setup */ |
| arch_timer_init(); |
| } |