[U-Boot] [PATCH v2] andes_spi: add andes_spi interface
Macpaul Lin
macpaul at andestech.com
Mon Apr 25 08:50:29 CEST 2011
andes_spi is an spi interface developed by Andes Tech.
Signed-off-by: Macpaul Lin <macpaul at andestech.com>
Cc: Wolfgang Denk <wd at denx.de>
Cc: Mike Frysinger <vapier at gentoo.org>
---
Changes for v2:
- Replace redundant length checking by min(len, 4).
- Remove redundant debug marco.
- Replace reading register in debug() by local variable.
- Add baud rate setup code (APB register) according to datasheet.
drivers/spi/Makefile | 1 +
drivers/spi/andes_spi.c | 294 +++++++++++++++++++++++++++++++++++++++++++++++
drivers/spi/andes_spi.h | 128 ++++++++++++++++++++
3 files changed, 423 insertions(+), 0 deletions(-)
create mode 100644 drivers/spi/andes_spi.c
create mode 100644 drivers/spi/andes_spi.h
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d582fbb..8ee8f68 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
LIB := $(obj)libspi.o
COBJS-$(CONFIG_ALTERA_SPI) += altera_spi.o
+COBJS-$(CONFIG_ANDES_SPI) += andes_spi.o
COBJS-$(CONFIG_ATMEL_DATAFLASH_SPI) += atmel_dataflash_spi.o
COBJS-$(CONFIG_ATMEL_SPI) += atmel_spi.o
COBJS-$(CONFIG_BFIN_SPI) += bfin_spi.o
diff --git a/drivers/spi/andes_spi.c b/drivers/spi/andes_spi.c
new file mode 100644
index 0000000..038d4f4
--- /dev/null
+++ b/drivers/spi/andes_spi.c
@@ -0,0 +1,294 @@
+/*
+ * Driver of Andes SPI Controller
+ *
+ * (C) Copyright 2011 Andes Technology
+ * Macpaul Lin <macpaul at andestech.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/io.h>
+#include "andes_spi.h"
+
+void spi_init()
+{
+ /* do nothing */
+}
+
+void andes_spi_spit_en(struct andes_spi_slave *ds)
+{
+ unsigned int dcr = readl(&ds->regs->dcr);
+
+ debug("%s: dcr: %x, write value: %x\n",
+ __func__, dcr, (dcr | ANDES_SPI_DCR_SPIT));
+
+ writel((dcr | ANDES_SPI_DCR_SPIT), &ds->regs->dcr);
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct andes_spi_slave *ds;
+
+ if (!spi_cs_is_valid(bus, cs))
+ return NULL;
+
+ ds = malloc(sizeof(*ds));
+ if (!ds)
+ return NULL;
+
+ ds->slave.bus = bus;
+ ds->slave.cs = cs;
+ ds->regs = (struct andes_spi_regs *)CONFIG_SYS_SPI_BASE;
+ ds->freq = max_hz;
+
+ return &ds->slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ struct andes_spi_slave *ds = to_andes_spi(slave);
+
+ free(ds);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ struct andes_spi_slave *ds = to_andes_spi(slave);
+ unsigned int apb = 0;
+ unsigned int baud = 0;
+
+ /* Enable the SPI hardware */
+ writel(ANDES_SPI_CR_SPIRST, &ds->regs->cr);
+ udelay(1000);
+
+ /* setup format */
+ baud = ((CONFIG_SYS_CLK_FREQ / CONFIG_SYS_SPI_CLK / 2) - 1) & 0xFF;
+
+ /*
+ * SPI_CLK = AHB bus clock / ((BAUD + 1)*2)
+ * BAUD = AHB bus clock / SPI_CLK / 2) - 1
+ */
+ apb = (readl(&ds->regs->apb) & 0xffffff00) | baud;
+ writel(apb, &ds->regs->apb);
+
+ /* no interrupts */
+ writel(0, &ds->regs->ie);
+
+ return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+ struct andes_spi_slave *ds = to_andes_spi(slave);
+
+ /* Disable the SPI hardware */
+ writel(ANDES_SPI_CR_SPIRST, &ds->regs->cr);
+}
+
+static int andes_spi_read(struct spi_slave *slave, unsigned int len,
+ u8 *rxp, unsigned long flags)
+{
+ struct andes_spi_slave *ds = to_andes_spi(slave);
+ unsigned int i = 0, left = 0;
+ unsigned int data = 0;
+
+ debug("%s: slave: %x, len: %d, rxp: %x, flags: %d\n",
+ __func__, slave, len, rxp, flags);
+
+ debug("%s: data: ", __func__);
+ while (len > 0) {
+ left = min(len, 4);
+ data = readl(&ds->regs->data);
+
+ debug(" ");
+ for (i = 0; i < left; i++) {
+ debug("%02x ", data & 0xff);
+ *rxp++ = data;
+ data >>= 8;
+ len--;
+ }
+ }
+ debug("\n");
+
+ return 0;
+}
+
+static int andes_spi_write(struct spi_slave *slave, unsigned int wlen,
+ unsigned int rlen, const u8 *txp, unsigned long flags)
+{
+ struct andes_spi_slave *ds = to_andes_spi(slave);
+ unsigned int data = 0;
+ unsigned int i, left;
+ unsigned int spit_enabled = 0;
+
+ debug("%s: slave: %x, wlen: %d, rlen: %d, txp: %x, flags: %x\n",
+ __func__, slave, wlen, rlen, txp, flags);
+
+ /* The value of wlen and rlen wrote to register must minus 1 */
+ if (rlen == 0) /* write only */
+ writel(ANDES_SPI_DCR_MODE_WO | ANDES_SPI_DCR_WCNT(wlen-1) |
+ ANDES_SPI_DCR_RCNT(0), &ds->regs->dcr);
+ else /* write then read */
+ writel(ANDES_SPI_DCR_MODE_WR | ANDES_SPI_DCR_WCNT(wlen-1) |
+ ANDES_SPI_DCR_RCNT(rlen-1), &ds->regs->dcr);
+
+ /* wait till SPIBSY is cleared */
+ while (readl(&ds->regs->st) & ANDES_SPI_ST_SPIBSY)
+ ;
+
+ /* data write process */
+ debug("%s: txp: ", __func__);
+ while (wlen > 0) {
+ /* data are usually be read 32bits once a time */
+ left = min(wlen, 4);
+
+ for (i = 0; i < left; i++) {
+ debug("%x ", *txp);
+ data |= *txp++ << (i * 8);
+ wlen--;
+ }
+ debug("\n");
+
+ debug("data: %08x\n", data);
+ debug("streg before write: %08x\n", readl(&ds->regs->st));
+ /* wait till TXFULL is deasserted */
+ while (readl(&ds->regs->st) & ANDES_SPI_ST_TXFEL)
+ ;
+ writel(data, &ds->regs->data);
+ debug("streg after write: %08x\n", readl(&ds->regs->st));
+
+ data = 0;
+
+ if (spit_enabled == 0) {
+ /* enable SPIT bit - trigger the tx and rx progress */
+ andes_spi_spit_en(ds);
+ spit_enabled = 1;
+ }
+
+ }
+ debug("\n");
+
+ return 0;
+}
+
+/*
+ * spi_xfer:
+ * Since andes_spi doesn't support independent command transaction,
+ * that is, write and than read must be operated in continuous
+ * execution, there is no need to set dcr and trigger spit again in
+ * RX process.
+ */
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ unsigned int len;
+ static int op_nextime;
+ static u8 tmp_cmd[5];
+ static int tmp_wlen;
+ unsigned int i;
+
+ if (bitlen == 0)
+ /* Finish any previously submitted transfers */
+ goto out;
+
+ if (bitlen % 8) {
+ /* Errors always terminate an ongoing transfer */
+ flags |= SPI_XFER_END;
+ goto out;
+ }
+
+ len = bitlen / 8;
+
+ debug("%s: slave: %08x, bitlen: %d, dout: "
+ "%08x, din: %08x, flags: %d, len: %d\n",
+ __func__, slave, bitlen, dout, din, flags, len);
+
+ /*
+ * Important:
+ * andes_spi's hardware doesn't support 2 data channel. The read
+ * and write cmd/data share the same register (data register).
+ *
+ * If a command has write and read transaction, you cannot do write
+ * this time and then do read on next time.
+ *
+ * A command writes first with a read response must indicating
+ * the read length in write operation. Hence the write action must
+ * be stored temporary and wait until the next read action has been
+ * arrived. Then we flush the write and read action out together.
+ */
+ if (!dout) {
+ if (op_nextime == 1) {
+ /* flags should be SPI_XFER_END, value is 2 */
+ op_nextime = 0;
+ andes_spi_write(slave, tmp_wlen, len, tmp_cmd, flags);
+ }
+ return andes_spi_read(slave, len, din, flags);
+ } else if (!din) {
+ if (flags == SPI_XFER_BEGIN) {
+ /* store the write command and do operation next time */
+ op_nextime = 1;
+ memset(tmp_cmd, 0, sizeof(tmp_cmd));
+ memcpy(tmp_cmd, dout, len);
+
+ debug("%s: tmp_cmd: ", __func__);
+ for (i = 0; i < len; i++)
+ debug("%x ", *(tmp_cmd + i));
+ debug("\n");
+
+ tmp_wlen = len;
+ } else {
+ /*
+ * flags should be (SPI_XFER_BEGIN | SPI_XFER_END),
+ * the value is 3.
+ */
+ if (op_nextime == 1) {
+ /* flags should be SPI_XFER_END, value is 2 */
+ op_nextime = 0;
+ /* flags 3 implies write only */
+ andes_spi_write(slave, tmp_wlen, 0, tmp_cmd, 3);
+ }
+
+ debug("flags: %x\n", flags);
+ return andes_spi_write(slave, len, 0, dout, flags);
+ }
+ }
+
+out:
+ 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 */
+}
diff --git a/drivers/spi/andes_spi.h b/drivers/spi/andes_spi.h
new file mode 100644
index 0000000..844bdba
--- /dev/null
+++ b/drivers/spi/andes_spi.h
@@ -0,0 +1,128 @@
+/*
+ * Register definitions for the Andes SPI Controller
+ *
+ * (C) Copyright 2011 Andes Technology
+ * Macpaul Lin <macpaul at andestech.com>
+ *
+ * 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
+ */
+
+#ifndef __ANDES_SPI_H
+#define __ANDES_SPI_H
+
+struct andes_spi_regs {
+ unsigned int apb; /* 0x00 - APB SPI interface setting */
+ unsigned int pio; /* 0x04 - PIO reg */
+ unsigned int cr; /* 0x08 - SPI Control reg */
+ unsigned int st; /* 0x0c - SPI Status reg */
+ unsigned int ie; /* 0x10 - Interrupt Enable reg */
+ unsigned int ist; /* 0x14 - Interrupt Status reg */
+ unsigned int dcr; /* 0x18 - data control reg */
+ unsigned int data; /* 0x1c - data register */
+ unsigned int ahb; /* 0x20 - AHB SPI interface setting */
+ unsigned int ver; /* 0x3c - SPI version reg */
+};
+
+#define BIT(x) (1 << (x))
+
+/* 0x00 - APB SPI interface setting register */
+#define ANDES_SPI_APB_BAUD(x) (((x) & 0xff) < 0)
+#define ANDES_SPI_APB_CSHT(x) (((x) & 0xf) < 16)
+#define ANDES_SPI_APB_SPNTS BIT(20) /* 0: normal, 1: delay */
+#define ANDES_SPI_APB_CPHA BIT(24) /* 0: Sampling at odd edges */
+#define ANDES_SPI_APB_CPOL BIT(25) /* 0: SCK low, 1: SCK high */
+#define ANDES_SPI_APB_MSSL BIT(26) /* 0: SPI Master, 1: slave */
+
+/* 0x04 - PIO register */
+#define ANDES_SPI_PIO_MISO BIT(0) /* input value of pin MISO */
+#define ANDES_SPI_PIO_MOSI BIT(1) /* I/O value of pin MOSI */
+#define ANDES_SPI_PIO_SCK BIT(2) /* I/O value of pin SCK */
+#define ANDES_SPI_PIO_CS BIT(3) /* I/O value of pin CS */
+#define ANDES_SPI_PIO_PIOE BIT(4) /* Programming IO Enable */
+
+/* 0x08 - SPI Control register */
+#define ANDES_SPI_CR_SPIRST BIT(0) /* SPI mode reset */
+#define ANDES_SPI_CR_RXFRST BIT(1) /* RxFIFO reset */
+#define ANDES_SPI_CR_TXFRST BIT(2) /* TxFIFO reset */
+#define ANDES_SPI_CR_RXFTH(x) (((x) & 0x1f) << 10) /* RxFIFO Threshold */
+#define ANDES_SPI_CR_TXFTH(x) (((x) & 0x1f) << 18) /* TxFIFO Threshold */
+
+/* 0x0c - SPI Status register */
+#define ANDES_SPI_ST_SPIBSY BIT(0) /* SPI Transfer is active */
+#define ANDES_SPI_ST_RXFEM BIT(8) /* RxFIFO Empty Flag */
+#define ANDES_SPI_ST_RXFEL BIT(9) /* RxFIFO Full Flag */
+#define ANDES_SPI_ST_RXFVE(x) (((x) >> 10) & 0x1f)
+#define ANDES_SPI_ST_TXFEM BIT(16) /* TxFIFO Empty Flag */
+#define ANDES_SPI_ST_TXFEL BIT(7) /* TxFIFO Full Flag */
+#define ANDES_SPI_ST_TXFVE(x) (((x) >> 18) & 0x1f)
+
+/* 0x10 - Interrupt Enable register */
+#define ANDES_SPI_IE_RXFORIE BIT(0) /* RxFIFO overrun intr */
+#define ANDES_SPI_IE_TXFURIE BIT(1) /* TxFOFO underrun intr */
+#define ANDES_SPI_IE_RXFTHIE BIT(2) /* RxFIFO threshold intr */
+#define ANDES_SPI_IE_TXFTHIE BIT(3) /* TxFIFO threshold intr */
+#define ANDES_SPI_IE_SPIEIE BIT(4) /* SPI transmit END intr */
+#define ANDES_SPI_IE_SPCFIE BIT(5) /* AHB/APB TxReq conflict */
+
+/* 0x14 - Interrupt Status Register */
+#define ANDES_SPI_IST_RXFORI BIT(0) /* has RxFIFO overrun */
+#define ANDES_SPI_IST_TXFURI BIT(1) /* has TxFOFO underrun */
+#define ANDES_SPI_IST_RXFTHI BIT(2) /* has RxFIFO threshold */
+#define ANDES_SPI_IST_TXFTHI BIT(3) /* has TxFIFO threshold */
+#define ANDES_SPI_IST_SPIEI BIT(4) /* has SPI transmit END */
+#define ANDES_SPI_IST_SPCFI BIT(5) /* has AHB/APB TxReq conflict */
+
+/* 0x18 - Data Control Register */
+#define ANDES_SPI_DCR_RCNT(x) (((x) & 0x3ff) << 0)
+#define ANDES_SPI_DCR_DYCNT(x) (((x) & 0x7) << 12)
+#define ANDES_SPI_DCR_WCNT(x) (((x) & 0x3ff) << 16)
+#define ANDES_SPI_DCR_TRAMODE(x) (((x) & 0x7) << 28)
+#define ANDES_SPI_DCR_SPIT BIT(31) /* SPI bus trigger */
+
+#define ANDES_SPI_DCR_MODE_WRCON ANDES_SPI_DCR_TRAMODE(0) /* w/r at the same time */
+#define ANDES_SPI_DCR_MODE_WO ANDES_SPI_DCR_TRAMODE(1) /* write only */
+#define ANDES_SPI_DCR_MODE_RO ANDES_SPI_DCR_TRAMODE(2) /* read only */
+#define ANDES_SPI_DCR_MODE_WR ANDES_SPI_DCR_TRAMODE(3) /* write, read */
+#define ANDES_SPI_DCR_MODE_RW ANDES_SPI_DCR_TRAMODE(4) /* read, write */
+#define ANDES_SPI_DCR_MODE_WDR ANDES_SPI_DCR_TRAMODE(5) /* write, dummy, read */
+#define ANDES_SPI_DCR_MODE_RDW ANDES_SPI_DCR_TRAMODE(6) /* read, dummy, write */
+#define ANDES_SPI_DCR_MODE_RECEIVE ANDES_SPI_DCR_TRAMODE(7) /* receive */
+
+/* 0x20 - AHB SPI interface setting register */
+#define ANDES_SPI_AHB_BAUD(x) (((x) & 0xff) < 0)
+#define ANDES_SPI_AHB_CSHT(x) (((x) & 0xf) < 16)
+#define ANDES_SPI_AHB_SPNTS BIT(20) /* 0: normal, 1: delay */
+#define ANDES_SPI_AHB_CPHA BIT(24) /* 0: Sampling at odd edges */
+#define ANDES_SPI_AHB_CPOL BIT(25) /* 0: SCK low, 1: SCK high */
+#define ANDES_SPI_AHB_MSSL BIT(26) /* only Master mode */
+
+/* 0x3c - Version Register - (Year V.MAJOR.MINOR) */
+#define ANDES_SPI_VER_MINOR(x) (((x) >> 0) & 0xf)
+#define ANDES_SPI_VER_MAJOR(x) (((x) >> 8) & 0xf)
+#define ANDES_SPI_VER_YEAR(x) (((x) >> 16) & 0xf)
+
+struct andes_spi_slave {
+ struct spi_slave slave;
+ struct andes_spi_regs *regs;
+ unsigned int freq;
+};
+
+static inline struct andes_spi_slave *to_andes_spi(struct spi_slave *slave)
+{
+ return container_of(slave, struct andes_spi_slave, slave);
+}
+
+#endif /* __ANDES_SPI_H */
--
1.7.3.5
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