u-boot/arch/arm/cpu/tegra20-common/clock.c
Lucas Stach 65530a842e tegra20: add clock_set_pllout function
Common practice on Tegra 2 boards is to use the pllp_out4 FO
to generate the ULPI reference clock. For this to work we have
to override the default hardware generated output divider.

This function adds a clean way to do so.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-10-15 11:54:07 -07:00

1126 lines
28 KiB
C

/*
* 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 <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,
};
/*
* 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),
};
/* 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 */
};
/*
* 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:
case PERIPH_ID_RESERVED91:
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);
}
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;
}
/**
* 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,
&divider_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]);
}