diff options
Diffstat (limited to 'arch/arm/cpu/tegra20-common/clock.c')
| -rw-r--r-- | arch/arm/cpu/tegra20-common/clock.c | 1087 | 
1 files changed, 1087 insertions, 0 deletions
| diff --git a/arch/arm/cpu/tegra20-common/clock.c b/arch/arm/cpu/tegra20-common/clock.c new file mode 100644 index 000000000..24038745b --- /dev/null +++ b/arch/arm/cpu/tegra20-common/clock.c @@ -0,0 +1,1087 @@ +/* + * 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 + */ + +/* Tegra20 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/tegra20.h> +#include <common.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, +}; + +/* + * Clock types that we can use as a source. The Tegra20 has muxes for the + * peripheral clocks, and in most cases there are four options for the clock + * source. This gives us a clock 'type' and exploits what commonality exists + * in the device. + * + * Letters are obvious, except for T which means CLK_M, and S which means the + * clock derived from 32KHz. Beware that CLK_M (also called OSC in the + * datasheet) and PLL_M are different things. The former is the basic + * clock supplied to the SOC from an external oscillator. The latter is the + * memory clock PLL. + * + * See definitions in clock_id in the header file. + */ +enum clock_type_id { +	CLOCK_TYPE_AXPT,	/* PLL_A, PLL_X, PLL_P, CLK_M */ +	CLOCK_TYPE_MCPA,	/* and so on */ +	CLOCK_TYPE_MCPT, +	CLOCK_TYPE_PCM, +	CLOCK_TYPE_PCMT, +	CLOCK_TYPE_PCMT16,	/* CLOCK_TYPE_PCMT with 16-bit divider */ +	CLOCK_TYPE_PCXTS, +	CLOCK_TYPE_PDCT, + +	CLOCK_TYPE_COUNT, +	CLOCK_TYPE_NONE = -1,	/* invalid clock type */ +}; + +/* 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 */ + +enum { +	CLOCK_MAX_MUX	= 4	/* number of source options for each clock */ +}; + +/* + * Clock source mux for each clock type. This just converts our enum into + * a list of mux sources for use by the code. Note that CLOCK_TYPE_PCXTS + * is special as it has 5 sources. Since it also has a different number of + * bits in its register for the source, we just handle it with a special + * case in the code. + */ +#define CLK(x) CLOCK_ID_ ## x +static enum clock_id clock_source[CLOCK_TYPE_COUNT][CLOCK_MAX_MUX] = { +	{ CLK(AUDIO),	CLK(XCPU),	CLK(PERIPH),	CLK(OSC)	}, +	{ CLK(MEMORY),	CLK(CGENERAL),	CLK(PERIPH),	CLK(AUDIO)	}, +	{ CLK(MEMORY),	CLK(CGENERAL),	CLK(PERIPH),	CLK(OSC)	}, +	{ CLK(PERIPH),	CLK(CGENERAL),	CLK(MEMORY),	CLK(NONE)	}, +	{ CLK(PERIPH),	CLK(CGENERAL),	CLK(MEMORY),	CLK(OSC)	}, +	{ CLK(PERIPH),	CLK(CGENERAL),	CLK(MEMORY),	CLK(OSC)	}, +	{ CLK(PERIPH),	CLK(CGENERAL),	CLK(XCPU),	CLK(OSC)	}, +	{ CLK(PERIPH),	CLK(DISPLAY),	CLK(CGENERAL),	CLK(OSC)	}, +}; + +/* + * Clock peripheral IDs which sadly don't match up with PERIPH_ID. This is + * not in the header file since it is for purely internal use - we want + * callers to use the PERIPH_ID for all access to peripheral clocks to avoid + * confusion bewteen PERIPH_ID_... and PERIPHC_... + * + * We don't call this CLOCK_PERIPH_ID or PERIPH_CLOCK_ID as it would just be + * confusing. + * + * Note to SOC vendors: perhaps define a unified numbering for peripherals and + * use it for reset, clock enable, clock source/divider and even pinmuxing + * if you can. + */ +enum periphc_internal_id { +	/* 0x00 */ +	PERIPHC_I2S1, +	PERIPHC_I2S2, +	PERIPHC_SPDIF_OUT, +	PERIPHC_SPDIF_IN, +	PERIPHC_PWM, +	PERIPHC_SPI1, +	PERIPHC_SPI2, +	PERIPHC_SPI3, + +	/* 0x08 */ +	PERIPHC_XIO, +	PERIPHC_I2C1, +	PERIPHC_DVC_I2C, +	PERIPHC_TWC, +	PERIPHC_0c, +	PERIPHC_10,	/* PERIPHC_SPI1, what is this really? */ +	PERIPHC_DISP1, +	PERIPHC_DISP2, + +	/* 0x10 */ +	PERIPHC_CVE, +	PERIPHC_IDE0, +	PERIPHC_VI, +	PERIPHC_1c, +	PERIPHC_SDMMC1, +	PERIPHC_SDMMC2, +	PERIPHC_G3D, +	PERIPHC_G2D, + +	/* 0x18 */ +	PERIPHC_NDFLASH, +	PERIPHC_SDMMC4, +	PERIPHC_VFIR, +	PERIPHC_EPP, +	PERIPHC_MPE, +	PERIPHC_MIPI, +	PERIPHC_UART1, +	PERIPHC_UART2, + +	/* 0x20 */ +	PERIPHC_HOST1X, +	PERIPHC_21, +	PERIPHC_TVO, +	PERIPHC_HDMI, +	PERIPHC_24, +	PERIPHC_TVDAC, +	PERIPHC_I2C2, +	PERIPHC_EMC, + +	/* 0x28 */ +	PERIPHC_UART3, +	PERIPHC_29, +	PERIPHC_VI_SENSOR, +	PERIPHC_2b, +	PERIPHC_2c, +	PERIPHC_SPI4, +	PERIPHC_I2C3, +	PERIPHC_SDMMC3, + +	/* 0x30 */ +	PERIPHC_UART4, +	PERIPHC_UART5, +	PERIPHC_VDE, +	PERIPHC_OWR, +	PERIPHC_NOR, +	PERIPHC_CSITE, + +	PERIPHC_COUNT, + +	PERIPHC_NONE = -1, +}; + +/* return 1 if a periphc_internal_id is in range */ +#define periphc_internal_id_isvalid(id) ((id) >= 0 && \ +		(id) < PERIPHC_COUNT) + +/* + * Clock type for each peripheral clock source. We put the name in each + * record just so it is easy to match things up + */ +#define TYPE(name, type) type +static enum clock_type_id clock_periph_type[PERIPHC_COUNT] = { +	/* 0x00 */ +	TYPE(PERIPHC_I2S1,	CLOCK_TYPE_AXPT), +	TYPE(PERIPHC_I2S2,	CLOCK_TYPE_AXPT), +	TYPE(PERIPHC_SPDIF_OUT,	CLOCK_TYPE_AXPT), +	TYPE(PERIPHC_SPDIF_IN,	CLOCK_TYPE_PCM), +	TYPE(PERIPHC_PWM,	CLOCK_TYPE_PCXTS), +	TYPE(PERIPHC_SPI1,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_SPI22,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_SPI3,	CLOCK_TYPE_PCMT), + +	/* 0x08 */ +	TYPE(PERIPHC_XIO,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_I2C1,	CLOCK_TYPE_PCMT16), +	TYPE(PERIPHC_DVC_I2C,	CLOCK_TYPE_PCMT16), +	TYPE(PERIPHC_TWC,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_SPI1,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_DISP1,	CLOCK_TYPE_PDCT), +	TYPE(PERIPHC_DISP2,	CLOCK_TYPE_PDCT), + +	/* 0x10 */ +	TYPE(PERIPHC_CVE,	CLOCK_TYPE_PDCT), +	TYPE(PERIPHC_IDE0,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_VI,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_SDMMC1,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_SDMMC2,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_G3D,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_G2D,	CLOCK_TYPE_MCPA), + +	/* 0x18 */ +	TYPE(PERIPHC_NDFLASH,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_SDMMC4,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_VFIR,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_EPP,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_MPE,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_MIPI,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_UART1,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_UART2,	CLOCK_TYPE_PCMT), + +	/* 0x20 */ +	TYPE(PERIPHC_HOST1X,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_TVO,	CLOCK_TYPE_PDCT), +	TYPE(PERIPHC_HDMI,	CLOCK_TYPE_PDCT), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_TVDAC,	CLOCK_TYPE_PDCT), +	TYPE(PERIPHC_I2C2,	CLOCK_TYPE_PCMT16), +	TYPE(PERIPHC_EMC,	CLOCK_TYPE_MCPT), + +	/* 0x28 */ +	TYPE(PERIPHC_UART3,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_VI,	CLOCK_TYPE_MCPA), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_NONE,	CLOCK_TYPE_NONE), +	TYPE(PERIPHC_SPI4,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_I2C3,	CLOCK_TYPE_PCMT16), +	TYPE(PERIPHC_SDMMC3,	CLOCK_TYPE_PCMT), + +	/* 0x30 */ +	TYPE(PERIPHC_UART4,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_UART5,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_VDE,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_OWR,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_NOR,	CLOCK_TYPE_PCMT), +	TYPE(PERIPHC_CSITE,	CLOCK_TYPE_PCMT), +}; + +/* + * This array translates a periph_id to a periphc_internal_id + * + * Not present/matched up: + *	uint vi_sensor;	 _VI_SENSOR_0,		0x1A8 + *	SPDIF - which is both 0x08 and 0x0c + * + */ +#define NONE(name) (-1) +#define OFFSET(name, value) PERIPHC_ ## name +static s8 periph_id_to_internal_id[PERIPH_ID_COUNT] = { +	/* Low word: 31:0 */ +	NONE(CPU), +	NONE(RESERVED1), +	NONE(RESERVED2), +	NONE(AC97), +	NONE(RTC), +	NONE(TMR), +	PERIPHC_UART1, +	PERIPHC_UART2,	/* and vfir 0x68 */ + +	/* 0x08 */ +	NONE(GPIO), +	PERIPHC_SDMMC2, +	NONE(SPDIF),		/* 0x08 and 0x0c, unclear which to use */ +	PERIPHC_I2S1, +	PERIPHC_I2C1, +	PERIPHC_NDFLASH, +	PERIPHC_SDMMC1, +	PERIPHC_SDMMC4, + +	/* 0x10 */ +	PERIPHC_TWC, +	PERIPHC_PWM, +	PERIPHC_I2S2, +	PERIPHC_EPP, +	PERIPHC_VI, +	PERIPHC_G2D, +	NONE(USBD), +	NONE(ISP), + +	/* 0x18 */ +	PERIPHC_G3D, +	PERIPHC_IDE0, +	PERIPHC_DISP2, +	PERIPHC_DISP1, +	PERIPHC_HOST1X, +	NONE(VCP), +	NONE(RESERVED30), +	NONE(CACHE2), + +	/* Middle word: 63:32 */ +	NONE(MEM), +	NONE(AHBDMA), +	NONE(APBDMA), +	NONE(RESERVED35), +	NONE(KBC), +	NONE(STAT_MON), +	NONE(PMC), +	NONE(FUSE), + +	/* 0x28 */ +	NONE(KFUSE), +	NONE(SBC1),	/* SBC1, 0x34, is this SPI1? */ +	PERIPHC_NOR, +	PERIPHC_SPI1, +	PERIPHC_SPI2, +	PERIPHC_XIO, +	PERIPHC_SPI3, +	PERIPHC_DVC_I2C, + +	/* 0x30 */ +	NONE(DSI), +	PERIPHC_TVO,	/* also CVE 0x40 */ +	PERIPHC_MIPI, +	PERIPHC_HDMI, +	PERIPHC_CSITE, +	PERIPHC_TVDAC, +	PERIPHC_I2C2, +	PERIPHC_UART3, + +	/* 0x38 */ +	NONE(RESERVED56), +	PERIPHC_EMC, +	NONE(USB2), +	NONE(USB3), +	PERIPHC_MPE, +	PERIPHC_VDE, +	NONE(BSEA), +	NONE(BSEV), + +	/* Upper word 95:64 */ +	NONE(SPEEDO), +	PERIPHC_UART4, +	PERIPHC_UART5, +	PERIPHC_I2C3, +	PERIPHC_SPI4, +	PERIPHC_SDMMC3, +	NONE(PCIE), +	PERIPHC_OWR, + +	/* 0x48 */ +	NONE(AFI), +	NONE(CORESIGHT), +	NONE(RESERVED74), +	NONE(AVPUCQ), +	NONE(RESERVED76), +	NONE(RESERVED77), +	NONE(RESERVED78), +	NONE(RESERVED79), + +	/* 0x50 */ +	NONE(RESERVED80), +	NONE(RESERVED81), +	NONE(RESERVED82), +	NONE(RESERVED83), +	NONE(IRAMA), +	NONE(IRAMB), +	NONE(IRAMC), +	NONE(IRAMD), + +	/* 0x58 */ +	NONE(CRAM2), +}; + +/* + * 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; +} + +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; +} + +/* return 1 if a peripheral ID is in range and valid */ +static int clock_periph_id_isvalid(enum periph_id id) +{ +	if (id < PERIPH_ID_FIRST || id >= PERIPH_ID_COUNT) +		printf("Peripheral id %d out of range\n", id); +	else { +		switch (id) { +		case PERIPH_ID_RESERVED1: +		case PERIPH_ID_RESERVED2: +		case PERIPH_ID_RESERVED30: +		case PERIPH_ID_RESERVED35: +		case PERIPH_ID_RESERVED56: +		case PERIPH_ID_RESERVED74: +		case PERIPH_ID_RESERVED76: +		case PERIPH_ID_RESERVED77: +		case PERIPH_ID_RESERVED78: +		case PERIPH_ID_RESERVED79: +		case PERIPH_ID_RESERVED80: +		case PERIPH_ID_RESERVED81: +		case PERIPH_ID_RESERVED82: +		case PERIPH_ID_RESERVED83: +			printf("Peripheral id %d is reserved\n", id); +			break; +		default: +			return 1; +		} +	} +	return 0; +} + +/* Returns a pointer to the clock source register for a peripheral */ +static u32 *get_periph_source_reg(enum periph_id periph_id) +{ +	struct clk_rst_ctlr *clkrst = +			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE; +	enum periphc_internal_id internal_id; + +	assert(clock_periph_id_isvalid(periph_id)); +	internal_id = periph_id_to_internal_id[periph_id]; +	assert(internal_id != -1); +	return &clkrst->crc_clk_src[internal_id]; +} + +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; +} + +/** + * 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; +} + +/** + * Given a peripheral ID and the required source clock, this returns which + * value should be programmed into the source mux for that peripheral. + * + * There is special code here to handle the one source type with 5 sources. + * + * @param periph_id	peripheral to start + * @param source	PLL id of required parent clock + * @param mux_bits	Set to number of bits in mux register: 2 or 4 + * @param divider_bits	Set to number of divider bits (8 or 16) + * @return mux value (0-4, or -1 if not found) + */ +static int get_periph_clock_source(enum periph_id periph_id, +		enum clock_id parent, int *mux_bits, int *divider_bits) +{ +	enum clock_type_id type; +	enum periphc_internal_id internal_id; +	int mux; + +	assert(clock_periph_id_isvalid(periph_id)); + +	internal_id = periph_id_to_internal_id[periph_id]; +	assert(periphc_internal_id_isvalid(internal_id)); + +	type = clock_periph_type[internal_id]; +	assert(clock_type_id_isvalid(type)); + +	/* +	 * Special cases here for the clock with a 4-bit source mux and I2C +	 * with its 16-bit divisor +	 */ +	if (type == CLOCK_TYPE_PCXTS) +		*mux_bits = 4; +	else +		*mux_bits = 2; +	if (type == CLOCK_TYPE_PCMT16) +		*divider_bits = 16; +	else +		*divider_bits = 8; + +	for (mux = 0; mux < CLOCK_MAX_MUX; mux++) +		if (clock_source[type][mux] == parent) +			return mux; + +	/* +	 * Not found: it might be looking for the 'S' in CLOCK_TYPE_PCXTS +	 * which is not in our table. If not, then they are asking for a +	 * source which this peripheral can't access through its mux. +	 */ +	assert(type == CLOCK_TYPE_PCXTS); +	assert(parent == CLOCK_ID_SFROM32KHZ); +	if (type == CLOCK_TYPE_PCXTS && parent == CLOCK_ID_SFROM32KHZ) +		return 4;	/* mux value for this clock */ + +	/* if we get here, either us or the caller has made a mistake */ +	printf("Caller requested bad clock: periph=%d, parent=%d\n", periph_id, +		parent); +	return -1; +} + +/** + * 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; + +	/* work out the source clock and set it */ +	source = get_periph_clock_source(periph_id, parent, &mux_bits, +					 ÷r_bits); + +	if (extra_div) +		divider = find_best_divider(divider_bits, pll_rate[parent], +					    rate, extra_div); +	else +		divider = clk_get_divider(divider_bits, pll_rate[parent], +					  rate); +	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_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. Tegra20 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); +} + +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 + */ +static 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 +/* + * Convert a device tree clock ID to our peripheral ID. They are mostly + * the same but we are very cautious so we check that a valid clock ID is + * provided. + * + * @param clk_id	Clock ID according to tegra20 device tree binding + * @return peripheral ID, or PERIPH_ID_NONE if the clock ID is invalid + */ +static enum periph_id clk_id_to_periph_id(int clk_id) +{ +	if (clk_id > 95) +		return PERIPH_ID_NONE; + +	switch (clk_id) { +	case 1: +	case 2: +	case 7: +	case 10: +	case 20: +	case 30: +	case 35: +	case 49: +	case 56: +	case 74: +	case 76: +	case 77: +	case 78: +	case 79: +	case 80: +	case 81: +	case 82: +	case 83: +	case 91: +	case 95: +		return PERIPH_ID_NONE; +	default: +		return clk_id; +	} +} + +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("PLLX %x is correct\n", reg); +	return 0; +} + +void clock_early_init(void) +{ +	/* +	 * PLLP output frequency set to 216MHz +	 * PLLC output frequency set to 600Mhz +	 * +	 * TODO: Can we calculate these values instead of hard-coding? +	 */ +	switch (clock_get_osc_freq()) { +	case CLOCK_OSC_FREQ_12_0: /* OSC is 12Mhz */ +		clock_set_rate(CLOCK_ID_PERIPH, 432, 12, 1, 8); +		clock_set_rate(CLOCK_ID_CGENERAL, 600, 12, 0, 8); +		break; + +	case CLOCK_OSC_FREQ_26_0: /* OSC is 26Mhz */ +		clock_set_rate(CLOCK_ID_PERIPH, 432, 26, 1, 8); +		clock_set_rate(CLOCK_ID_CGENERAL, 600, 26, 0, 8); +		break; + +	case CLOCK_OSC_FREQ_13_0: /* OSC is 13Mhz */ +		clock_set_rate(CLOCK_ID_PERIPH, 432, 13, 1, 8); +		clock_set_rate(CLOCK_ID_CGENERAL, 600, 13, 0, 8); +		break; +	case CLOCK_OSC_FREQ_19_2: +	default: +		/* +		 * These are not supported. It is too early to print a +		 * message and the UART likely won't work anyway due to the +		 * oscillator being wrong. +		 */ +		break; +	} +} + +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; +	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]); +} |