X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=drivers%2Fspi%2Fdavinci_spi.c;h=0a036ccb009a81093069b5377b62c0baa9592e11;hb=fa31377ef0fd1096fbeab9c240582a93c4da9f6d;hp=ebc7f8082ba016c842f3d6836ce1825b5f7c28b5;hpb=8ed5885693b39c5c2cca5574dd98d6ad8a982702;p=oweals%2Fu-boot.git diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c index ebc7f8082b..0a036ccb00 100644 --- a/drivers/spi/davinci_spi.c +++ b/drivers/spi/davinci_spi.c @@ -6,32 +6,280 @@ * * Copyright (C) 2007 Atmel Corporation * - * 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 + * SPDX-License-Identifier: GPL-2.0+ */ + #include #include #include #include #include -#include "davinci_spi.h" -void spi_init() +#define BIT(x) (1 << (x)) + +/* SPIGCR0 */ +#define SPIGCR0_SPIENA_MASK 0x1 +#define SPIGCR0_SPIRST_MASK 0x0 + +/* SPIGCR0 */ +#define SPIGCR1_CLKMOD_MASK BIT(1) +#define SPIGCR1_MASTER_MASK BIT(0) +#define SPIGCR1_SPIENA_MASK BIT(24) + +/* SPIPC0 */ +#define SPIPC0_DIFUN_MASK BIT(11) /* SIMO */ +#define SPIPC0_DOFUN_MASK BIT(10) /* SOMI */ +#define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */ +#define SPIPC0_EN0FUN_MASK BIT(0) + +/* SPIFMT0 */ +#define SPIFMT_SHIFTDIR_SHIFT 20 +#define SPIFMT_POLARITY_SHIFT 17 +#define SPIFMT_PHASE_SHIFT 16 +#define SPIFMT_PRESCALE_SHIFT 8 + +/* SPIDAT1 */ +#define SPIDAT1_CSHOLD_SHIFT 28 +#define SPIDAT1_CSNR_SHIFT 16 + +/* SPIDELAY */ +#define SPI_C2TDELAY_SHIFT 24 +#define SPI_T2CDELAY_SHIFT 16 + +/* SPIBUF */ +#define SPIBUF_RXEMPTY_MASK BIT(31) +#define SPIBUF_TXFULL_MASK BIT(29) + +/* SPIDEF */ +#define SPIDEF_CSDEF0_MASK BIT(0) + +#define SPI0_BUS 0 +#define SPI0_BASE CONFIG_SYS_SPI_BASE +/* + * Define default SPI0_NUM_CS as 1 for existing platforms that uses this + * driver. Platform can configure number of CS using CONFIG_SYS_SPI0_NUM_CS + * if more than one CS is supported and by defining CONFIG_SYS_SPI0. + */ +#ifndef CONFIG_SYS_SPI0 +#define SPI0_NUM_CS 1 +#else +#define SPI0_NUM_CS CONFIG_SYS_SPI0_NUM_CS +#endif + +/* + * define CONFIG_SYS_SPI1 when platform has spi-1 device (bus #1) and + * CONFIG_SYS_SPI1_NUM_CS defines number of CS on this bus + */ +#ifdef CONFIG_SYS_SPI1 +#define SPI1_BUS 1 +#define SPI1_NUM_CS CONFIG_SYS_SPI1_NUM_CS +#define SPI1_BASE CONFIG_SYS_SPI1_BASE +#endif + +/* + * define CONFIG_SYS_SPI2 when platform has spi-2 device (bus #2) and + * CONFIG_SYS_SPI2_NUM_CS defines number of CS on this bus + */ +#ifdef CONFIG_SYS_SPI2 +#define SPI2_BUS 2 +#define SPI2_NUM_CS CONFIG_SYS_SPI2_NUM_CS +#define SPI2_BASE CONFIG_SYS_SPI2_BASE +#endif + +/* davinci spi register set */ +struct davinci_spi_regs { + dv_reg gcr0; /* 0x00 */ + dv_reg gcr1; /* 0x04 */ + dv_reg int0; /* 0x08 */ + dv_reg lvl; /* 0x0c */ + dv_reg flg; /* 0x10 */ + dv_reg pc0; /* 0x14 */ + dv_reg pc1; /* 0x18 */ + dv_reg pc2; /* 0x1c */ + dv_reg pc3; /* 0x20 */ + dv_reg pc4; /* 0x24 */ + dv_reg pc5; /* 0x28 */ + dv_reg rsvd[3]; + dv_reg dat0; /* 0x38 */ + dv_reg dat1; /* 0x3c */ + dv_reg buf; /* 0x40 */ + dv_reg emu; /* 0x44 */ + dv_reg delay; /* 0x48 */ + dv_reg def; /* 0x4c */ + dv_reg fmt0; /* 0x50 */ + dv_reg fmt1; /* 0x54 */ + dv_reg fmt2; /* 0x58 */ + dv_reg fmt3; /* 0x5c */ + dv_reg intvec0; /* 0x60 */ + dv_reg intvec1; /* 0x64 */ +}; + +/* davinci spi slave */ +struct davinci_spi_slave { + struct spi_slave slave; + struct davinci_spi_regs *regs; + unsigned int freq; +}; + +static inline struct davinci_spi_slave *to_davinci_spi(struct spi_slave *slave) +{ + return container_of(slave, struct davinci_spi_slave, slave); +} + +/* + * This functions needs to act like a macro to avoid pipeline reloads in the + * loops below. Use always_inline. This gains us about 160KiB/s and the bloat + * appears to be zero bytes (da830). + */ +__attribute__((always_inline)) +static inline u32 davinci_spi_xfer_data(struct davinci_spi_slave *ds, u32 data) +{ + u32 buf_reg_val; + + /* send out data */ + writel(data, &ds->regs->dat1); + + /* wait for the data to clock in/out */ + while ((buf_reg_val = readl(&ds->regs->buf)) & SPIBUF_RXEMPTY_MASK) + ; + + return buf_reg_val; +} + +static int davinci_spi_read(struct spi_slave *slave, unsigned int len, + u8 *rxp, unsigned long flags) +{ + struct davinci_spi_slave *ds = to_davinci_spi(slave); + unsigned int data1_reg_val; + + /* enable CS hold, CS[n] and clear the data bits */ + data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) | + (slave->cs << SPIDAT1_CSNR_SHIFT)); + + /* wait till TXFULL is deasserted */ + while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK) + ; + + /* preload the TX buffer to avoid clock starvation */ + writel(data1_reg_val, &ds->regs->dat1); + + /* keep reading 1 byte until only 1 byte left */ + while ((len--) > 1) + *rxp++ = davinci_spi_xfer_data(ds, data1_reg_val); + + /* clear CS hold when we reach the end */ + if (flags & SPI_XFER_END) + data1_reg_val &= ~(1 << SPIDAT1_CSHOLD_SHIFT); + + /* read the last byte */ + *rxp = davinci_spi_xfer_data(ds, data1_reg_val); + + return 0; +} + +static int davinci_spi_write(struct spi_slave *slave, unsigned int len, + const u8 *txp, unsigned long flags) +{ + struct davinci_spi_slave *ds = to_davinci_spi(slave); + unsigned int data1_reg_val; + + /* enable CS hold and clear the data bits */ + data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) | + (slave->cs << SPIDAT1_CSNR_SHIFT)); + + /* wait till TXFULL is deasserted */ + while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK) + ; + + /* preload the TX buffer to avoid clock starvation */ + if (len > 2) { + writel(data1_reg_val | *txp++, &ds->regs->dat1); + len--; + } + + /* keep writing 1 byte until only 1 byte left */ + while ((len--) > 1) + davinci_spi_xfer_data(ds, data1_reg_val | *txp++); + + /* clear CS hold when we reach the end */ + if (flags & SPI_XFER_END) + data1_reg_val &= ~(1 << SPIDAT1_CSHOLD_SHIFT); + + /* write the last byte */ + davinci_spi_xfer_data(ds, data1_reg_val | *txp); + + return 0; +} + +#ifndef CONFIG_SPI_HALF_DUPLEX +static int davinci_spi_read_write(struct spi_slave *slave, unsigned int len, + u8 *rxp, const u8 *txp, unsigned long flags) +{ + struct davinci_spi_slave *ds = to_davinci_spi(slave); + unsigned int data1_reg_val; + + /* enable CS hold and clear the data bits */ + data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) | + (slave->cs << SPIDAT1_CSNR_SHIFT)); + + /* wait till TXFULL is deasserted */ + while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK) + ; + + /* keep reading and writing 1 byte until only 1 byte left */ + while ((len--) > 1) + *rxp++ = davinci_spi_xfer_data(ds, data1_reg_val | *txp++); + + /* clear CS hold when we reach the end */ + if (flags & SPI_XFER_END) + data1_reg_val &= ~(1 << SPIDAT1_CSHOLD_SHIFT); + + /* read and write the last byte */ + *rxp = davinci_spi_xfer_data(ds, data1_reg_val | *txp); + + return 0; +} +#endif + +int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ + int ret = 0; + + switch (bus) { + case SPI0_BUS: + if (cs < SPI0_NUM_CS) + ret = 1; + break; +#ifdef CONFIG_SYS_SPI1 + case SPI1_BUS: + if (cs < SPI1_NUM_CS) + ret = 1; + break; +#endif +#ifdef CONFIG_SYS_SPI2 + case SPI2_BUS: + if (cs < SPI2_NUM_CS) + ret = 1; + break; +#endif + default: + /* Invalid bus number. Do nothing */ + break; + } + return ret; +} + +void spi_cs_activate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void spi_cs_deactivate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void spi_init(void) { /* do nothing */ } @@ -44,13 +292,28 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, if (!spi_cs_is_valid(bus, cs)) return NULL; - ds = malloc(sizeof(*ds)); + ds = spi_alloc_slave(struct davinci_spi_slave, bus, cs); if (!ds) return NULL; - ds->slave.bus = bus; - ds->slave.cs = cs; - ds->regs = (struct davinci_spi_regs *)CONFIG_SYS_SPI_BASE; + switch (bus) { + case SPI0_BUS: + ds->regs = (struct davinci_spi_regs *)SPI0_BASE; + break; +#ifdef CONFIG_SYS_SPI1 + case SPI1_BUS: + ds->regs = (struct davinci_spi_regs *)SPI1_BASE; + break; +#endif +#ifdef CONFIG_SYS_SPI2 + case SPI2_BUS: + ds->regs = (struct davinci_spi_regs *)SPI2_BASE; + break; +#endif + default: /* Invalid bus number */ + return NULL; + } + ds->freq = max_hz; return &ds->slave; @@ -66,7 +329,7 @@ void spi_free_slave(struct spi_slave *slave) int spi_claim_bus(struct spi_slave *slave) { struct davinci_spi_slave *ds = to_davinci_spi(slave); - unsigned int scalar, data1_reg_val = 0; + unsigned int scalar; /* Enable the SPI hardware */ writel(SPIGCR0_SPIRST_MASK, &ds->regs->gcr0); @@ -77,7 +340,7 @@ int spi_claim_bus(struct spi_slave *slave) writel(SPIGCR1_MASTER_MASK | SPIGCR1_CLKMOD_MASK, &ds->regs->gcr1); /* CS, CLK, SIMO and SOMI are functional pins */ - writel((SPIPC0_EN0FUN_MASK | SPIPC0_CLKFUN_MASK | + writel(((1 << slave->cs) | SPIPC0_CLKFUN_MASK | SPIPC0_DOFUN_MASK | SPIPC0_DIFUN_MASK), &ds->regs->pc0); /* setup format */ @@ -93,11 +356,6 @@ int spi_claim_bus(struct spi_slave *slave) writel(8 | (scalar << SPIFMT_PRESCALE_SHIFT) | (1 << SPIFMT_PHASE_SHIFT), &ds->regs->fmt0); - /* hold cs active at end of transfer until explicitly de-asserted */ - data1_reg_val = (1 << SPIDAT1_CSHOLD_SHIFT) | - (slave->cs << SPIDAT1_CSNR_SHIFT); - writel(data1_reg_val, &ds->regs->dat1); - /* * Including a minor delay. No science here. Should be good even with * no delay @@ -127,15 +385,9 @@ void spi_release_bus(struct spi_slave *slave) } int spi_xfer(struct spi_slave *slave, unsigned int bitlen, - const void *dout, void *din, unsigned long flags) + const void *dout, void *din, unsigned long flags) { - struct davinci_spi_slave *ds = to_davinci_spi(slave); - unsigned int len, data1_reg_val = readl(&ds->regs->dat1); - int ret, i; - const u8 *txp = dout; /* dout can be NULL for read operation */ - u8 *rxp = din; /* din can be NULL for write operation */ - - ret = 0; + unsigned int len; if (bitlen == 0) /* Finish any previously submitted transfers */ @@ -155,69 +407,23 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, len = bitlen / 8; - /* do an empty read to clear the current contents */ - readl(&ds->regs->buf); - - /* keep writing and reading 1 byte until done */ - for (i = 0; i < len; i++) { - /* wait till TXFULL is asserted */ - while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK); - - /* write the data */ - data1_reg_val &= ~0xFFFF; - if (txp) { - data1_reg_val |= *txp; - txp++; - } - - /* - * Write to DAT1 is required to keep the serial transfer going. - * We just terminate when we reach the end. - */ - if ((i == (len - 1)) && (flags & SPI_XFER_END)) { - /* clear CS hold */ - writel(data1_reg_val & - ~(1 << SPIDAT1_CSHOLD_SHIFT), &ds->regs->dat1); - } else { - /* enable CS hold */ - data1_reg_val |= ((1 << SPIDAT1_CSHOLD_SHIFT) | - (slave->cs << SPIDAT1_CSNR_SHIFT)); - writel(data1_reg_val, &ds->regs->dat1); - } - - /* read the data - wait for data availability */ - while (readl(&ds->regs->buf) & SPIBUF_RXEMPTY_MASK); - - if (rxp) { - *rxp = readl(&ds->regs->buf) & 0xFF; - rxp++; - } else { - /* simply drop the read character */ - readl(&ds->regs->buf); - } - } - return 0; + if (!dout) + return davinci_spi_read(slave, len, din, flags); + else if (!din) + return davinci_spi_write(slave, len, dout, flags); +#ifndef CONFIG_SPI_HALF_DUPLEX + else + return davinci_spi_read_write(slave, len, din, dout, flags); +#else + printf("SPI full duplex transaction requested with " + "CONFIG_SPI_HALF_DUPLEX defined.\n"); + flags |= SPI_XFER_END; +#endif out: if (flags & SPI_XFER_END) { - writel(data1_reg_val & - ~(1 << SPIDAT1_CSHOLD_SHIFT), &ds->regs->dat1); + u8 dummy = 0; + davinci_spi_write(slave, 1, &dummy, flags); } return 0; } - -int spi_cs_is_valid(unsigned int bus, unsigned int cs) -{ - return bus == 0 && cs == 0; -} - -void spi_cs_activate(struct spi_slave *slave) -{ - /* do nothing */ -} - -void spi_cs_deactivate(struct spi_slave *slave) -{ - /* do nothing */ -} -