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Diffstat (limited to 'drivers/spi/altera_spi.c')
-rw-r--r--drivers/spi/altera_spi.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/spi/altera_spi.c b/drivers/spi/altera_spi.c
new file mode 100644
index 0000000..918b223
--- /dev/null
+++ b/drivers/spi/altera_spi.c
@@ -0,0 +1,165 @@
+/*
+ * Altera SPI driver
+ *
+ * based on bfin_spi.c
+ * Copyright (c) 2005-2008 Analog Devices Inc.
+ * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+#include <common.h>
+#include <asm/io.h>
+#include <malloc.h>
+#include <spi.h>
+
+#define ALTERA_SPI_RXDATA 0
+#define ALTERA_SPI_TXDATA 4
+#define ALTERA_SPI_STATUS 8
+#define ALTERA_SPI_CONTROL 12
+#define ALTERA_SPI_SLAVE_SEL 20
+
+#define ALTERA_SPI_STATUS_ROE_MSK (0x8)
+#define ALTERA_SPI_STATUS_TOE_MSK (0x10)
+#define ALTERA_SPI_STATUS_TMT_MSK (0x20)
+#define ALTERA_SPI_STATUS_TRDY_MSK (0x40)
+#define ALTERA_SPI_STATUS_RRDY_MSK (0x80)
+#define ALTERA_SPI_STATUS_E_MSK (0x100)
+
+#define ALTERA_SPI_CONTROL_IROE_MSK (0x8)
+#define ALTERA_SPI_CONTROL_ITOE_MSK (0x10)
+#define ALTERA_SPI_CONTROL_ITRDY_MSK (0x40)
+#define ALTERA_SPI_CONTROL_IRRDY_MSK (0x80)
+#define ALTERA_SPI_CONTROL_IE_MSK (0x100)
+#define ALTERA_SPI_CONTROL_SSO_MSK (0x400)
+
+#ifndef CONFIG_SYS_ALTERA_SPI_LIST
+#define CONFIG_SYS_ALTERA_SPI_LIST { CONFIG_SYS_SPI_BASE }
+#endif
+
+static ulong altera_spi_base_list[] = CONFIG_SYS_ALTERA_SPI_LIST;
+
+struct altera_spi_slave {
+ struct spi_slave slave;
+ ulong base;
+};
+#define to_altera_spi_slave(s) container_of(s, struct altera_spi_slave, slave)
+
+__attribute__((weak))
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ return bus < ARRAY_SIZE(altera_spi_base_list) && cs < 32;
+}
+
+__attribute__((weak))
+void spi_cs_activate(struct spi_slave *slave)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+ writel(1 << slave->cs, altspi->base + ALTERA_SPI_SLAVE_SEL);
+ writel(ALTERA_SPI_CONTROL_SSO_MSK, altspi->base + ALTERA_SPI_CONTROL);
+}
+
+__attribute__((weak))
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+ writel(0, altspi->base + ALTERA_SPI_CONTROL);
+ writel(0, altspi->base + ALTERA_SPI_SLAVE_SEL);
+}
+
+void spi_init(void)
+{
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct altera_spi_slave *altspi;
+
+ if (!spi_cs_is_valid(bus, cs))
+ return NULL;
+
+ altspi = malloc(sizeof(*altspi));
+ if (!altspi)
+ return NULL;
+
+ altspi->slave.bus = bus;
+ altspi->slave.cs = cs;
+ altspi->base = altera_spi_base_list[bus];
+ debug("%s: bus:%i cs:%i base:%lx\n", __func__,
+ bus, cs, altspi->base);
+
+ return &altspi->slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+ free(altspi);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+
+ debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
+ writel(0, altspi->base + ALTERA_SPI_CONTROL);
+ writel(0, altspi->base + ALTERA_SPI_SLAVE_SEL);
+ return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+
+ debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
+ writel(0, altspi->base + ALTERA_SPI_SLAVE_SEL);
+}
+
+#ifndef CONFIG_ALTERA_SPI_IDLE_VAL
+# define CONFIG_ALTERA_SPI_IDLE_VAL 0xff
+#endif
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
+ void *din, unsigned long flags)
+{
+ struct altera_spi_slave *altspi = to_altera_spi_slave(slave);
+ /* assume spi core configured to do 8 bit transfers */
+ uint bytes = bitlen / 8;
+ const uchar *txp = dout;
+ uchar *rxp = din;
+
+ debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__,
+ slave->bus, slave->cs, bitlen, bytes, flags);
+ if (bitlen == 0)
+ goto done;
+
+ if (bitlen % 8) {
+ flags |= SPI_XFER_END;
+ goto done;
+ }
+
+ /* empty read buffer */
+ if (readl(altspi->base + ALTERA_SPI_STATUS) &
+ ALTERA_SPI_STATUS_RRDY_MSK)
+ readl(altspi->base + ALTERA_SPI_RXDATA);
+ if (flags & SPI_XFER_BEGIN)
+ spi_cs_activate(slave);
+
+ while (bytes--) {
+ uchar d = txp ? *txp++ : CONFIG_ALTERA_SPI_IDLE_VAL;
+ debug("%s: tx:%x ", __func__, d);
+ writel(d, altspi->base + ALTERA_SPI_TXDATA);
+ while (!(readl(altspi->base + ALTERA_SPI_STATUS) &
+ ALTERA_SPI_STATUS_RRDY_MSK))
+ ;
+ d = readl(altspi->base + ALTERA_SPI_RXDATA);
+ if (rxp)
+ *rxp++ = d;
+ debug("rx:%x\n", d);
+ }
+ done:
+ if (flags & SPI_XFER_END)
+ spi_cs_deactivate(slave);
+
+ return 0;
+}