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-rw-r--r--arch/arm/cpu/armv7/tegra20/clock.c1087
1 files changed, 1087 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/tegra20/clock.c b/arch/arm/cpu/armv7/tegra20/clock.c
new file mode 100644
index 0000000000..24038745bd
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra20/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,
+ &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]);
+}
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