[U-Boot] [PATCH v2] spi: add support SuperH SPI module
Yoshihiro Shimoda
yoshihiro.shimoda.uh at renesas.com
Tue Jan 18 09:53:42 CET 2011
SH7757 has SPI module. This patch supports it.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh at renesas.com>
---
about v2:
- add prefix of "SH_" to some defines.
- modify spi_cs_is_valid()
drivers/spi/Makefile | 1 +
drivers/spi/sh_spi.c | 301 ++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 302 insertions(+), 0 deletions(-)
create mode 100644 drivers/spi/sh_spi.c
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index e34a124..d582fbb 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -37,6 +37,7 @@ COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o
COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o
COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o
COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o
+COBJS-$(CONFIG_SH_SPI) += sh_spi.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)
diff --git a/drivers/spi/sh_spi.c b/drivers/spi/sh_spi.c
new file mode 100644
index 0000000..633450c
--- /dev/null
+++ b/drivers/spi/sh_spi.c
@@ -0,0 +1,301 @@
+/*
+ * SH SPI driver
+ *
+ * Copyright (C) 2011 Renesas Solutions Corp.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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 St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/io.h>
+
+#define SH_SPI_TBR 0x00
+#define SH_SPI_RBR 0x00
+#define SH_SPI_CR1 0x08
+#define SH_SPI_CR2 0x10
+#define SH_SPI_CR3 0x18
+#define SH_SPI_CR4 0x20
+
+/* CR1 */
+#define SH_SPI_TBE 0x80
+#define SH_SPI_TBF 0x40
+#define SH_SPI_RBE 0x20
+#define SH_SPI_RBF 0x10
+#define SH_SPI_PFONRD 0x08
+#define SH_SPI_SSDB 0x04
+#define SH_SPI_SSD 0x02
+#define SH_SPI_SSA 0x01
+
+/* CR2 */
+#define SH_SPI_RSTF 0x80
+#define SH_SPI_LOOPBK 0x40
+#define SH_SPI_CPOL 0x20
+#define SH_SPI_CPHA 0x10
+#define SH_SPI_L1M0 0x08
+
+/* CR3 */
+#define SH_SPI_MAX_BYTE 0xFF
+
+/* CR4 */
+#define SH_SPI_TBEI 0x80
+#define SH_SPI_TBFI 0x40
+#define SH_SPI_RBEI 0x20
+#define SH_SPI_RBFI 0x10
+#define SH_SPI_WPABRT 0x04
+#define SH_SPI_SSS 0x01
+
+#define SH_SPI_FIFO_SIZE 32
+
+static void sh_spi_write(unsigned long data, unsigned long offset)
+{
+ writel(data, CONFIG_SH_SPI_BASE + offset);
+}
+
+static unsigned long sh_spi_read(unsigned long offset)
+{
+ return readl(CONFIG_SH_SPI_BASE + offset);
+}
+
+static void sh_spi_set_bit(unsigned long val, unsigned long offset)
+{
+ unsigned long tmp;
+
+ tmp = sh_spi_read(offset);
+ tmp |= val;
+ sh_spi_write(tmp, offset);
+}
+
+static void sh_spi_clear_bit(unsigned long val, unsigned long offset)
+{
+ unsigned long tmp;
+
+ tmp = sh_spi_read(offset);
+ tmp &= ~val;
+ sh_spi_write(tmp, offset);
+}
+
+static void clear_fifo(void)
+{
+ sh_spi_set_bit(SH_SPI_RSTF, SH_SPI_CR2);
+ sh_spi_clear_bit(SH_SPI_RSTF, SH_SPI_CR2);
+}
+
+static int recvbuf_wait(void)
+{
+ while (sh_spi_read(SH_SPI_CR1) & SH_SPI_RBE) {
+ if (ctrlc())
+ return 1;
+ udelay(10);
+ }
+ return 0;
+}
+
+static int write_fifo_full_wait(void)
+{
+ while (sh_spi_read(SH_SPI_CR1) & SH_SPI_TBF) {
+ udelay(10);
+ if (ctrlc())
+ return 1;
+ }
+ return 0;
+}
+
+static int write_fifo_empty_wait(void)
+{
+ while (!(sh_spi_read(SH_SPI_CR1) & SH_SPI_TBE)) {
+ if (ctrlc())
+ return 1;
+ udelay(10);
+ }
+ return 0;
+}
+
+void spi_init(void)
+{
+
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct spi_slave *slave;
+
+ 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;
+
+ /* SPI sycle stop */
+ sh_spi_write(0xfe, SH_SPI_CR1);
+ /* CR1 init */
+ sh_spi_write(0x00, SH_SPI_CR1);
+ /* CR3 init */
+ sh_spi_write(0x00, SH_SPI_CR3);
+
+ clear_fifo();
+
+ /* 1/8 clock */
+ sh_spi_write(sh_spi_read(SH_SPI_CR2) | 0x07, SH_SPI_CR2);
+ udelay(10);
+
+ 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)
+{
+ sh_spi_write(sh_spi_read(SH_SPI_CR1) &
+ ~(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD), SH_SPI_CR1);
+}
+
+static int sh_spi_send(const unsigned char *tx_data, unsigned int len,
+ unsigned long flags)
+{
+ int i, cur_len, ret = 0;
+ int remain = (int)len;
+ unsigned long tmp;
+
+ if (len >= SH_SPI_FIFO_SIZE)
+ sh_spi_set_bit(SH_SPI_SSA, SH_SPI_CR1);
+
+ while (remain > 0) {
+ cur_len = (remain < SH_SPI_FIFO_SIZE) ?
+ remain : SH_SPI_FIFO_SIZE;
+ for (i = 0; i < cur_len &&
+ !(sh_spi_read(SH_SPI_CR4) & SH_SPI_WPABRT) &&
+ !(sh_spi_read(SH_SPI_CR1) & SH_SPI_TBF);
+ i++)
+ sh_spi_write(tx_data[i], SH_SPI_TBR);
+
+ cur_len = i;
+
+ if (sh_spi_read(SH_SPI_CR4) & SH_SPI_WPABRT) {
+ /* Abort the transaction */
+ flags |= SPI_XFER_END;
+ sh_spi_set_bit(SH_SPI_WPABRT, SH_SPI_CR4);
+ ret = 1;
+ break;
+ }
+
+ remain -= cur_len;
+ tx_data += cur_len;
+
+ if (remain > 0)
+ write_fifo_empty_wait();
+ }
+
+ if (flags & SPI_XFER_END) {
+ tmp = sh_spi_read(SH_SPI_CR1);
+ tmp = tmp & ~(SH_SPI_SSD | SH_SPI_SSDB);
+ sh_spi_write(tmp, SH_SPI_CR1);
+ sh_spi_set_bit(SH_SPI_SSA, SH_SPI_CR1);
+ udelay(100);
+ write_fifo_empty_wait();
+ }
+
+ return ret;
+}
+
+static int sh_spi_receive(unsigned char *rx_data, unsigned int len,
+ unsigned long flags)
+{
+ int i;
+ unsigned long tmp;
+
+ if (len > SH_SPI_MAX_BYTE)
+ sh_spi_write(SH_SPI_MAX_BYTE, SH_SPI_CR3);
+ else
+ sh_spi_write(len, SH_SPI_CR3);
+
+ tmp = sh_spi_read(SH_SPI_CR1);
+ tmp = tmp & ~(SH_SPI_SSD | SH_SPI_SSDB);
+ sh_spi_write(tmp, SH_SPI_CR1);
+ sh_spi_set_bit(SH_SPI_SSA, SH_SPI_CR1);
+
+ for (i = 0; i < len; i++) {
+ if (recvbuf_wait())
+ return 0;
+
+ rx_data[i] = (unsigned char)sh_spi_read(SH_SPI_RBR);
+ }
+ sh_spi_write(0, SH_SPI_CR3);
+
+ return 0;
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
+ void *din, unsigned long flags)
+{
+ const unsigned char *tx_data = dout;
+ unsigned char *rx_data = din;
+ unsigned int len = bitlen / 8;
+ int ret = 0;
+
+ if (flags & SPI_XFER_BEGIN)
+ sh_spi_write(sh_spi_read(SH_SPI_CR1) & ~SH_SPI_SSA, SH_SPI_CR1);
+
+ if (tx_data)
+ ret = sh_spi_send(tx_data, len, flags);
+
+ if (ret == 0 && rx_data)
+ ret = sh_spi_receive(rx_data, len, flags);
+
+ if (flags & SPI_XFER_END) {
+ sh_spi_set_bit(SH_SPI_SSD, SH_SPI_CR1);
+ udelay(100);
+
+ sh_spi_clear_bit(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD,
+ SH_SPI_CR1);
+ clear_fifo();
+ }
+
+ return ret;
+}
+
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ /* This driver supports "bus = 0" and "cs = 0" only. */
+ if (!bus && !cs)
+ return 1;
+ else
+ return 0;
+}
+
+void spi_cs_activate(struct spi_slave *slave)
+{
+
+}
+
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+
+}
+
--
1.7.1
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