| /* |
| * Freescale Coldfire Queued SPI driver |
| * |
| * NOTE: |
| * This driver is written to transfer 8 bit at-a-time and uses the dedicated |
| * SPI slave select pins as bit-banged GPIO to work with spi_flash subsystem. |
| * |
| * |
| * Copyright (C) 2011 Ruggedcom, Inc. |
| * Richard Retanubun (richardretanubun@freescale.com) |
| * |
| * 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 |
| */ |
| |
| #include <common.h> |
| #include <malloc.h> |
| #include <spi.h> |
| #include <asm/immap.h> |
| #include <asm/io.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| #define clamp(x, low, high) (min(max(low, x), high)) |
| #define to_cf_qspi_slave(s) container_of(s, struct cf_qspi_slave, s) |
| |
| struct cf_qspi_slave { |
| struct spi_slave slave; /* Specific bus:cs ID for each device */ |
| qspi_t *regs; /* Pointer to SPI controller registers */ |
| u16 qmr; /* QMR: Queued Mode Register */ |
| u16 qwr; /* QWR: Queued Wrap Register */ |
| u16 qcr; /* QCR: Queued Command Ram */ |
| }; |
| |
| /* Register write wrapper functions */ |
| static void write_qmr(volatile qspi_t *qspi, u16 val) { qspi->mr = val; } |
| static void write_qdlyr(volatile qspi_t *qspi, u16 val) { qspi->dlyr = val; } |
| static void write_qwr(volatile qspi_t *qspi, u16 val) { qspi->wr = val; } |
| static void write_qir(volatile qspi_t *qspi, u16 val) { qspi->ir = val; } |
| static void write_qar(volatile qspi_t *qspi, u16 val) { qspi->ar = val; } |
| static void write_qdr(volatile qspi_t *qspi, u16 val) { qspi->dr = val; } |
| /* Register read wrapper functions */ |
| static u16 read_qdlyr(volatile qspi_t *qspi) { return qspi->dlyr; } |
| static u16 read_qwr(volatile qspi_t *qspi) { return qspi->wr; } |
| static u16 read_qir(volatile qspi_t *qspi) { return qspi->ir; } |
| static u16 read_qdr(volatile qspi_t *qspi) { return qspi->dr; } |
| |
| /* These call points may be different for each ColdFire CPU */ |
| extern void cfspi_port_conf(void); |
| static void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high); |
| static void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high); |
| |
| int spi_claim_bus(struct spi_slave *slave) |
| { |
| return 0; |
| } |
| void spi_release_bus(struct spi_slave *slave) |
| { |
| } |
| |
| __attribute__((weak)) |
| void spi_init(void) |
| { |
| cfspi_port_conf(); |
| } |
| |
| __attribute__((weak)) |
| void spi_cs_activate(struct spi_slave *slave) |
| { |
| struct cf_qspi_slave *dev = to_cf_qspi_slave(slave); |
| |
| cfspi_cs_activate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV)); |
| } |
| |
| __attribute__((weak)) |
| void spi_cs_deactivate(struct spi_slave *slave) |
| { |
| struct cf_qspi_slave *dev = to_cf_qspi_slave(slave); |
| |
| cfspi_cs_deactivate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV)); |
| } |
| |
| __attribute__((weak)) |
| int spi_cs_is_valid(unsigned int bus, unsigned int cs) |
| { |
| /* Only 1 bus and 4 chipselect per controller */ |
| if (bus == 0 && (cs >= 0 && cs < 4)) |
| return 1; |
| else |
| return 0; |
| } |
| |
| void spi_free_slave(struct spi_slave *slave) |
| { |
| struct cf_qspi_slave *dev = to_cf_qspi_slave(slave); |
| |
| free(dev); |
| } |
| |
| /* Translate information given by spi_setup_slave to members of cf_qspi_slave */ |
| struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, |
| unsigned int max_hz, unsigned int mode) |
| { |
| struct cf_qspi_slave *dev = NULL; |
| |
| if (!spi_cs_is_valid(bus, cs)) |
| return NULL; |
| |
| dev = spi_alloc_slave(struct cf_qspi_slave, bus, cs); |
| if (!dev) |
| return NULL; |
| |
| /* Initialize to known value */ |
| dev->regs = (qspi_t *)MMAP_QSPI; |
| dev->qmr = 0; |
| dev->qwr = 0; |
| dev->qcr = 0; |
| |
| |
| /* Map max_hz to QMR[BAUD] */ |
| if (max_hz == 0) /* Go as fast as possible */ |
| dev->qmr = 2u; |
| else /* Get the closest baud rate */ |
| dev->qmr = clamp(((gd->bus_clk >> 2) + max_hz - 1)/max_hz, |
| 2u, 255u); |
| |
| /* Map mode to QMR[CPOL] and QMR[CPHA] */ |
| if (mode & SPI_CPOL) |
| dev->qmr |= QSPI_QMR_CPOL; |
| |
| if (mode & SPI_CPHA) |
| dev->qmr |= QSPI_QMR_CPHA; |
| |
| /* Hardcode bit length to 8 bit per transter */ |
| dev->qmr |= QSPI_QMR_BITS_8; |
| |
| /* Set QMR[MSTR] to enable QSPI as master */ |
| dev->qmr |= QSPI_QMR_MSTR; |
| |
| /* |
| * Set QCR and QWR to default values for spi flash operation. |
| * If more custom QCR and QRW are needed, overload mode variable |
| */ |
| dev->qcr = (QSPI_QDR_CONT | QSPI_QDR_BITSE); |
| |
| if (!(mode & SPI_CS_HIGH)) |
| dev->qwr |= QSPI_QWR_CSIV; |
| |
| return &dev->slave; |
| } |
| |
| /* Transfer 8 bit at a time */ |
| int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, |
| void *din, unsigned long flags) |
| { |
| struct cf_qspi_slave *dev = to_cf_qspi_slave(slave); |
| volatile qspi_t *qspi = dev->regs; |
| u8 *txbuf = (u8 *)dout; |
| u8 *rxbuf = (u8 *)din; |
| u32 count = DIV_ROUND_UP(bitlen, 8); |
| u32 n, i = 0; |
| |
| /* Sanitize arguments */ |
| if (slave == NULL) { |
| printf("%s: NULL slave ptr\n", __func__); |
| return -1; |
| } |
| |
| if (flags & SPI_XFER_BEGIN) |
| spi_cs_activate(slave); |
| |
| /* There is something to send, lets process it. spi_xfer is also called |
| * just to toggle chip select, so bitlen of 0 is valid */ |
| if (count > 0) { |
| /* |
| * NOTE: Since chip select is driven as a bit-bang-ed GPIO |
| * using spi_cs_activate() and spi_cs_deactivate(), |
| * the chip select settings inside the controller |
| * (i.e. QCR[CONT] and QWR[CSIV]) are moot. The bits are set to |
| * keep the controller settings consistent with the actual |
| * operation of the bus. |
| */ |
| |
| /* Write the slave device's settings for the controller.*/ |
| write_qmr(qspi, dev->qmr); |
| write_qwr(qspi, dev->qwr); |
| |
| /* Limit transfer to 16 at a time */ |
| n = min(count, 16u); |
| do { |
| /* Setup queue end point */ |
| write_qwr(qspi, ((read_qwr(qspi) & QSPI_QWR_ENDQP_MASK) |
| | QSPI_QWR_ENDQP((n-1)))); |
| |
| /* Write Command RAM */ |
| write_qar(qspi, QSPI_QAR_CMD); |
| for (i = 0; i < n; ++i) |
| write_qdr(qspi, dev->qcr); |
| |
| /* Write TxBuf, if none given, fill with ZEROes */ |
| write_qar(qspi, QSPI_QAR_TRANS); |
| if (txbuf) { |
| for (i = 0; i < n; ++i) |
| write_qdr(qspi, *txbuf++); |
| } else { |
| for (i = 0; i < n; ++i) |
| write_qdr(qspi, 0); |
| } |
| |
| /* Clear QIR[SPIF] by writing a 1 to it */ |
| write_qir(qspi, read_qir(qspi) | QSPI_QIR_SPIF); |
| /* Set QDLYR[SPE] to start sending */ |
| write_qdlyr(qspi, read_qdlyr(qspi) | QSPI_QDLYR_SPE); |
| |
| /* Poll QIR[SPIF] for transfer completion */ |
| while ((read_qir(qspi) & QSPI_QIR_SPIF) != 1) |
| udelay(1); |
| |
| /* If given read RxBuf, load data to it */ |
| if (rxbuf) { |
| write_qar(qspi, QSPI_QAR_RECV); |
| for (i = 0; i < n; ++i) |
| *rxbuf++ = read_qdr(qspi); |
| } |
| |
| /* Decrement count */ |
| count -= n; |
| } while (count); |
| } |
| |
| if (flags & SPI_XFER_END) |
| spi_cs_deactivate(slave); |
| |
| return 0; |
| } |
| |
| /* Each MCF CPU may have different pin assignments for chip selects. */ |
| #if defined(CONFIG_M5271) |
| /* Assert chip select, val = [1|0] , dir = out, mode = GPIO */ |
| void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high) |
| { |
| debug("%s: bus %d cs %d cs_active_high %d\n", |
| __func__, bus, cs, cs_active_high); |
| |
| switch (cs) { |
| case 0: /* QSPI_CS[0] = PQSPI[3] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08); |
| else |
| mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_QSPI, |
| mbar_readByte(MCF_GPIO_PDDR_QSPI) | 0x08); |
| |
| mbar_writeByte(MCF_GPIO_PAR_QSPI, |
| mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF); |
| break; |
| case 1: /* QSPI_CS[1] = PQSPI[4] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10); |
| else |
| mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_QSPI, |
| mbar_readByte(MCF_GPIO_PDDR_QSPI) | 0x10); |
| |
| mbar_writeByte(MCF_GPIO_PAR_QSPI, |
| mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F); |
| break; |
| case 2: /* QSPI_CS[2] = PTIMER[7] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80); |
| else |
| mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_TIMER, |
| mbar_readByte(MCF_GPIO_PDDR_TIMER) | 0x80); |
| |
| mbar_writeShort(MCF_GPIO_PAR_TIMER, |
| mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF); |
| break; |
| case 3: /* QSPI_CS[3] = PTIMER[3] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08); |
| else |
| mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_TIMER, |
| mbar_readByte(MCF_GPIO_PDDR_TIMER) | 0x08); |
| |
| mbar_writeShort(MCF_GPIO_PAR_TIMER, |
| mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F); |
| break; |
| } |
| } |
| |
| /* Deassert chip select, val = [1|0], dir = in, mode = GPIO |
| * direction set as IN to undrive the pin, external pullup/pulldown will bring |
| * bus to deassert state. |
| */ |
| void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high) |
| { |
| debug("%s: bus %d cs %d cs_active_high %d\n", |
| __func__, bus, cs, cs_active_high); |
| |
| switch (cs) { |
| case 0: /* QSPI_CS[0] = PQSPI[3] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7); |
| else |
| mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_QSPI, |
| mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xF7); |
| |
| mbar_writeByte(MCF_GPIO_PAR_QSPI, |
| mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF); |
| break; |
| case 1: /* QSPI_CS[1] = PQSPI[4] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF); |
| else |
| mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_QSPI, |
| mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xEF); |
| |
| mbar_writeByte(MCF_GPIO_PAR_QSPI, |
| mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F); |
| break; |
| case 2: /* QSPI_CS[2] = PTIMER[7] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F); |
| else |
| mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_TIMER, |
| mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0x7F); |
| |
| mbar_writeShort(MCF_GPIO_PAR_TIMER, |
| mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF); |
| break; |
| case 3: /* QSPI_CS[3] = PTIMER[3] */ |
| if (cs_active_high) |
| mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7); |
| else |
| mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08); |
| |
| mbar_writeByte(MCF_GPIO_PDDR_TIMER, |
| mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0xF7); |
| |
| mbar_writeShort(MCF_GPIO_PAR_TIMER, |
| mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F); |
| break; |
| } |
| } |
| #endif /* CONFIG_M5271 */ |