[U-Boot] [PATCH v2 2/5] spi: Add Marvell Kirkwood SPI driver
Prafulla Wadaskar
prafulla at marvell.com
Tue Jun 2 12:07:34 CEST 2009
This patch adds a SPI driver for the Marvell Kirkwood SoC's.
Signed-off-by: Prafulla Wadaskar <prafulla at marvell.com>
---
Change log:
v2: White space in debug print removed
drivers/spi/Makefile | 1 +
drivers/spi/kirkwood_spi.c | 185 +++++++++++++++++++++++++++++++++++
include/asm-arm/arch-kirkwood/spi.h | 56 +++++++++++
3 files changed, 242 insertions(+), 0 deletions(-)
create mode 100644 drivers/spi/kirkwood_spi.c
create mode 100644 include/asm-arm/arch-kirkwood/spi.h
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 1350f3e..7ffa47d 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -28,6 +28,7 @@ LIB := $(obj)libspi.a
COBJS-$(CONFIG_ATMEL_DATAFLASH_SPI) += atmel_dataflash_spi.o
COBJS-$(CONFIG_ATMEL_SPI) += atmel_spi.o
COBJS-$(CONFIG_BFIN_SPI) += bfin_spi.o
+COBJS-$(CONFIG_KIRKWOOD_SPI) += kirkwood_spi.o
COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o
COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o
COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o
diff --git a/drivers/spi/kirkwood_spi.c b/drivers/spi/kirkwood_spi.c
new file mode 100644
index 0000000..a1c3070
--- /dev/null
+++ b/drivers/spi/kirkwood_spi.c
@@ -0,0 +1,185 @@
+/*
+ * (C) Copyright 2009
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla at marvell.com>
+ *
+ * Derived from drivers/spi/mpc8xxx_spi.c
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/arch/kirkwood.h>
+#include <asm/arch/spi.h>
+#include <asm/arch/mpp.h>
+
+static struct kwspi_registers *spireg = (struct kwspi_registers *)KW_SPI_BASE;
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct spi_slave *slave;
+ u32 data;
+ u32 kwspi_mpp_config[] = {
+ MPP0_GPIO,
+ MPP7_SPI_SCn,
+ 0
+ };
+
+ if (!spi_cs_is_valid(bus, cs))
+ return NULL;
+
+ slave = malloc(sizeof(struct spi_slave));
+ if (!slave)
+ return NULL;
+
+ slave->bus = bus;
+ slave->cs = cs;
+
+ writel(~KWSPI_CSN_ACT | KWSPI_SMEMRDY, &spireg->ctrl);
+
+ /* calculate spi clock prescaller using max_hz */
+ data = ((CONFIG_SYS_TCLK / 2) / max_hz) & KWSPI_CLKPRESCL_MASK;
+ data |= 0x10;
+
+ /* program spi clock prescaller using max_hz */
+ writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg);
+ debug("data = 0x%08x\n", data);
+
+ writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
+ writel(KWSPI_IRQMASK, spireg->irq_mask);
+
+ /* program mpp registers to select SPI_CSn */
+ if (cs) {
+ kwspi_mpp_config[0] = MPP0_GPIO;
+ kwspi_mpp_config[1] = MPP7_SPI_SCn;
+ } else {
+ kwspi_mpp_config[0] = MPP0_SPI_SCn;
+ kwspi_mpp_config[1] = MPP7_GPO;
+ }
+ kirkwood_mpp_conf(kwspi_mpp_config);
+
+ return slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ free(slave);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+}
+
+#ifndef CONFIG_SPI_CS_IS_VALID
+/*
+ * you can define this function board specific
+ * define above CONFIG in board specific config file and
+ * provide the function in board specific src file
+ */
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ return (bus == 0 && (cs == 0 || cs == 1));
+}
+#endif
+
+void spi_cs_activate(struct spi_slave *slave)
+{
+ writel(readl(&spireg->ctrl) | KWSPI_IRQUNMASK, &spireg->ctrl);
+}
+
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+ writel(readl(&spireg->ctrl) & KWSPI_IRQMASK, &spireg->ctrl);
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
+ void *din, unsigned long flags)
+{
+ unsigned int tmpdout, tmpdin;
+ int tm, isread = 0;
+
+ debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
+ slave->bus, slave->cs, dout, din, bitlen);
+
+ if (flags & SPI_XFER_BEGIN)
+ spi_cs_activate(slave);
+
+ /*
+ * handle data in 8-bit chunks
+ * TBD: 2byte xfer mode to be enabled
+ */
+ writel(((readl(&spireg->cfg) & ~KWSPI_XFERLEN_MASK) |
+ KWSPI_XFERLEN_1BYTE), &spireg->cfg);
+
+ while (bitlen > 4) {
+ debug("loopstart bitlen %d\n", bitlen);
+ tmpdout = 0;
+
+ /* Shift data so it's msb-justified */
+ if (dout)
+ tmpdout = *(u32 *) dout & 0x0ff;
+
+ writel(~KWSPI_SMEMRDIRQ, &spireg->irq_cause);
+ writel(tmpdout, &spireg->dout); /* Write the data out */
+ debug("*** spi_xfer: ... %08x written, bitlen %d\n",
+ tmpdout, bitlen);
+
+ /*
+ * Wait for SPI transmit to get out
+ * or time out (1 second = 1000 ms)
+ * The NE event must be read and cleared first
+ */
+ for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
+ if (readl(&spireg->irq_cause) & KWSPI_SMEMRDIRQ) {
+ isread = 1;
+ tmpdin = readl(&spireg->din);
+ debug
+ ("spi_xfer: din %08x..%08x read\n",
+ din, tmpdin);
+
+ if (din) {
+ *((u8 *) din) = (u8) tmpdin;
+ din += 1;
+ }
+ if (dout)
+ dout += 1;
+ bitlen -= 8;
+ }
+ if (isread)
+ break;
+ }
+ if (tm >= KWSPI_TIMEOUT)
+ printf("*** spi_xfer: Time out during SPI transfer\n");
+
+ debug("loopend bitlen %d\n", bitlen);
+ }
+
+ if (flags & SPI_XFER_END)
+ spi_cs_deactivate(slave);
+
+ return 0;
+}
diff --git a/include/asm-arm/arch-kirkwood/spi.h b/include/asm-arm/arch-kirkwood/spi.h
new file mode 100644
index 0000000..1d5043f
--- /dev/null
+++ b/include/asm-arm/arch-kirkwood/spi.h
@@ -0,0 +1,56 @@
+/*
+ * (C) Copyright 2009
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla at marvell.com>
+ *
+ * Derived from drivers/spi/mpc8xxx_spi.c
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#ifndef __KW_SPI_H__
+#define __KW_SPI_H__
+
+/* SPI Registers on kirkwood SOC */
+struct kwspi_registers {
+ u32 ctrl; /* 0x10600 */
+ u32 cfg; /* 0x10604 */
+ u32 dout; /* 0x10608 */
+ u32 din; /* 0x1060c */
+ u32 irq_cause; /* 0x10610 */
+ u32 irq_mask; /* 0x10614 */
+};
+
+#define KWSPI_CLKPRESCL_MASK 0x1f
+#define KWSPI_CSN_ACT 1 /* Activates serial memory interface */
+#define KWSPI_SMEMRDY (1 << 1) /* SerMem Data xfer ready */
+#define KWSPI_IRQUNMASK 1 /* unmask SPI interrupt */
+#define KWSPI_IRQMASK 0 /* mask SPI interrupt */
+#define KWSPI_SMEMRDIRQ 1 /* SerMem data xfer ready irq */
+#define KWSPI_XFERLEN_1BYTE 0
+#define KWSPI_XFERLEN_2BYTE (1 << 5)
+#define KWSPI_XFERLEN_MASK (1 << 5)
+#define KWSPI_ADRLEN_1BYTE 0
+#define KWSPI_ADRLEN_2BYTE 1 << 8
+#define KWSPI_ADRLEN_3BYTE 2 << 8
+#define KWSPI_ADRLEN_4BYTE 3 << 8
+#define KWSPI_ADRLEN_MASK 3 << 8
+#define KWSPI_TIMEOUT 10000
+
+#endif /* __KW_SPI_H__ */
--
1.5.3.3
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