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Diffstat (limited to 'drivers/spi/cf_qspi.c')
-rw-r--r--drivers/spi/cf_qspi.c373
1 files changed, 373 insertions, 0 deletions
diff --git a/drivers/spi/cf_qspi.c b/drivers/spi/cf_qspi.c
new file mode 100644
index 0000000..72dd1a5
--- /dev/null
+++ b/drivers/spi/cf_qspi.c
@@ -0,0 +1,373 @@
+/*
+ * 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 = malloc(sizeof(struct cf_qspi_slave));
+ if (!dev)
+ return NULL;
+
+ /* Initialize to known value */
+ dev->slave.bus = bus;
+ dev->slave.cs = cs;
+ 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 = ((bitlen / 8) + (bitlen % 8 ? 1 : 0));
+ 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 */
generated by cgit v1.1 at 2024-12-14 19:39:46 +0000